DICTIONARY OF MANUFACTURES, MINING, MACHINERY, AND THE INDUSTRIAL ARTS, BY GEORGE DODD, II AUTHOR OF BRITISH MANUFACTURES;" " CURIOSITIES OF INDUSTRY," ETC., ETC. NEW YORK: VIRTUE AND YORSTON, 12, DEY STREET. Entered, according to Act of Congress, in the year One Thousand Eight Hundred and Sixty-nine, BY VIRTUE AND YORSTON, In the Clerk's Office of the District Court of the United States for the Southern District of New York. PREFACE. THIS work a small book on a great subject treats, in alphabetical arrangement, of those numerous matters which come generally within the range of manufactures and the productive arts. The raw materials animal, vegetable, and mineral whence the manufactured products are derived are succinctly noticed in connection with the processes which they undergo, but not as subjects of natural history. The operations of the Mine and the Mill, the Foundry and the Forge, the Factory and the Workshop, are passed under review. The principal machines and engines, tools and apparatus, concerned in manufacturing processes, are briefly described. The scale on which our chief branches of national industry are conducted, in regard to values and quantities, is indicated in various ways. The volume must be taken simply as a compendium of the various subjects to which it relates a succinct account of the leading facts. If it serves as an introduction to, or a brief and handy substitute for, more bulky and costly works, it will have fulfilled its purpose. Confined pretty closely to the matters denoted by its title, the Dic- tionary touches only in a cursory way on scientific topics. The physical and chemical laws which supply a basis for the industrial arts must necessarily be noticed so far as to render the processes intelligible ; but scientific investigations per se, irrespectively of their practical applica- tion, are not included. Nor has it been deemed expedient to include the vast subject of Civil Engineering. The earth -work, concrete-work, brick-work, stone-work, wood-work, and iron- work, whereby the bold conceptions of the engineei are realised, are mechanically and technically similar to those concerned in ordinary building operations ; but the scientific elaboration of plan, the largeness of scale, and the grandeur of result, place the great works 155683 PREFACE. of civil engineering in a class by themselves. Railways, cuttings, tunnels, embankments, viaducts, bridges, aqueducts, canals, locks, docks, quays, harbours, sea walls, breakwaters, lighthouses, drainage, sewers, water supply, river improvements, land reclamations, may well have a com- panion volume to the present devoted to them. The author has supplemented his own acquaintance with the subjects treated in this volume by information derived from trustworthy sources. Among such sources may be named Tomlinson's comprehensive and accurate " Cyclopaedia of Useful Arts ; " Hunt's recent edition of " Ure's Dictionary of Arts and Manufactures ; " Reports of the several International Industrial Exhibitions, held at Hyde Parkin 1851, New York in 1853, Paris in 1855, Brompton in 1862, and Paris in 1867 ; Proceedings of the British Association, and of the Social Science Congress ; Industrial and Statistical Papers of various kinds included among the Parliamentary Blue-books ; and the Reports of Proceed- ings before the Society of Arts and the Scientific bodies. A few facts have been derived from Cola's recent volume (" How to Develop Productive Industry in India and the East," Virtue & Co., 1867). As a native of India, directly connected with the cotton manufacture at Bombay, Mr. Cola has traced the manner in which English-made machinery may best be employed in India ; and to facilitate his work, he has given the present prices of a considerable range of machines. This being a kind of information not often met with in books, a few of his items are given in this Dictionary under their proper headings. DICTIONARY MANUFACTURES, MI ETC. ABR AGR Abrasion is that mode of me- chanically wearing down a surface which is illustrated in the well- known action of the file, the grind- stone, emery-paper, &c. Absinthe is one of the numerous kinds of Liqueurs (which see). Accordion. (See HARMONIUM.) Acetic Acid. The form which this acid usually presents is noticed under VINEGAR. Acids. Such only of the nume- rous bodies under this general name as are most useful in the manufac- turing arts will require notice in this work ; some under the names of the acids themselves (sulphuric acid, for instance), others under various head- ings. Adhesion, or the tendency of sur- faces to remain in contact, has much to do with friction. Hence, in ar- ranging the parts of machinery, attention is (or ought to be) paid to the degree of force with which dif- ferent substances tend to adhere or cling one to another. Adze is a tool something in form between an axe and a chisel, with a handle more like the former and a blade more like the latter. It acts upon wood a good deal like a wedge, and is especially valuable to ship- wrights. The blade is usually from 2 Ibs. to 4 Ibs. weight. Aerated Bread. (See BREAD MAKING.) Aerated Water forms one class of Mineral Waters (which see). Aeronautics is the science of balloons and balloon ascents. What little we need say about it will be found under BALLOON. Ag-ate. (See GEMS AND PRE- CIOUS STONES.) Agricultural Machines. Con- sidered as a science, agriculture re- lates to the action of air, warmth, moisture, and contact with chemical substances in producing the growth of plants. Considered as an art, it treats of the means of bringing all these agencies together. The imple- ments or tools for doing this the spade, fork, hoe, &c., and the sickle and scythe for reaping the produce have been known from early ages ; and most of them are too simple to need description. The substitution, however, of machines for tools is no- where producing more remarkable effects than in the agricultural dis- tricts, where more corn can now be produced per acre than was ever before possible, and with a much smaller expenditure of manual la- bour. There are two distinct classes of these machines worked by mus- cular power and steam power re- spectively. An interesting notice is given by Mr. Cola of the kinds of implements that would be useful in India, and that have indeed been constructed with that view ; a great improvement on anything hitherto used in that country, and yet not requiring steam power to work them. Iron plough, made either for light AGR ALA or heavy soils, and capable of being used for paring, ridging, or subsoil- ing, as well as for ploughing ; 2 to 3^ cwt. ; 6 to ^15. Potato-raising plough, adapted for places where large crops of potatoes are raised ; 3 to 4 acres raised per day with 2 horses ; ^6 to ^"8. Dwarf iron plough, for shallow ploughing, worked by a bullock, ^3 to ^5. Iron harrow, 2 to 4 beams, 5 to 6 rows of teeth ; I to 2\ cwt. ; 6 to 8. Double-action Haymaking machine, 7\ to 12 cwt., ^14 to ^"20. Threshing machine, to be worked by bullocks, 56 to ^"lOO. Grass- cutting and reaping machine, 20 to ^30. Irrigation pumps, to raise 4,000 gallons per hour, and worked by bullocks, ^150. The steam- worked machines are of course much more expensive. Steam cultivator, with ploughing apparatus, windlass, steel ropes, harrows, and portable steam-engine mounted on wheels, ;6oo to ;8oo if working on the single-engine system ; ;8oo to ^1,500 if on the double. Steam threshing machine, mounted on wheels complete, ^150 to .500. Steam centrifugal pump, for irriga- tion ; i o to 20 feet high, and raising 500 to 4,000 gallons per hour ; ^"75 to 280. Disintegrator, for pulverising bone, bone-ash, guano, &c., for manure, ^"80. The steam cultivator does two kinds of work at once cutting up new ground, and preparing that which has already been turned up ; the same engine can also be used for other purposes. The steam thresh- ing machine threshes and winnows the corn, shakes out the straw, and delivers the grain into bags ; there is sometimes also a straw chopper, to cut the straw into small pieces. More than 100,000 reaping machines are now sold annually in the United States. One of them, with 2 horses, will reap 15 acres of corn in 10 hours, at one-third of the cost and at one -twentieth of the time neces- sary for a hand-sickle. It is sup- posed that 1 2,000 agricultural steam- engines are now at work in the United Kingdom, moving the various steam-worked machines ; and the number is rapidly increas- ing. (See further under STEAM FARMING.) Air Cushions. To make an elastic bed, pillow, bolster, or cushion, by stuffing a bag or case with air, was difficult, until water and air-proof cloth were brought into requisition ; but mackintosh or india-rubber cloth renders it easy enough. The whole bag may be filled, or it may consist of a series of tubes side by side. A very con- venient arrangement is to have a metal stop-cock at one corner of the cushion, by which the air can be readily blown in or pressed out. Air Engine. Heated air and con- densed air are now both of them used as substitutes for steam as a prime mover. (See COMPRESSED-AIR ENGINE and HOT- AIR ENGINE.) Air Gun is an apparatus with a piston or plunger to condense air into a receiver. When a valve is opened, the outrush of air is siiffi- cient to project a bullet, but to no great distance. Some of the air- guns made, especially on Martin's plan, have much the appearance of muskets or rifles. Air Pump. So far as an air- j pump takes part in machines and i manufactures, it is noticed in such i articles as STEAM ENGINE, &c. It is really a pump, drawing out air instead of water, and acting by- means of levers, pipes, valves, and other mechanical appliances. The air-pump of the lecture-room is a more refined apparatus. Alabaster is a fine and compact form of gypsum, or sulphate of lime. Being soft in texture and delicately white, it is used as a material for can-ing or sculpturing into statuettes, busts, vases, &c. ; but being at the same time very ALA ALL fragile, and difficult to clean when soiled, it requires careful handling. Italy is the chief storehouse for the finest specimens of alabaster. In working it up into ornamental forms, the same processes nearly are adopted as the lapidary em- ploys for amber, coral, jet, and malachite. In sculpturing and carv- ing, as distinguished from lapidary work, the alabaster is subjected to the action of pointed chisels for roughing out, flat chisels for smooth- ing, gouges for convex and concave surfaces, bent rasps and files, triangular scrapers, dried fish-skin, Dutch rush, glass-paper, sand and water, and putty powder. It may be either polished or left matt by varying the processes. Fibrous gypsum, or satinstone, is worked into necklaces, &c. Stalagmite, or Oriental alabaster, much harder than the common kind, and vari- ously coloured, has been sculp- tured into magnificent sarcophagi, &c. Alarum is a watch or clock that strikes at a particular hour. An ordinary clock strikes on a bell once an hour ; and by a small addition to the apparatus, it can be made to strike at any inter- mediate time, or to give a ringing succession of sounds loud enough to wake a sleeper. The alarum can be " set " beforehand, so as to act at the required time. A tell- tale clock is a kind of alarum in which there are a number of pins sticking round the dial. Each pin can be pushed into a hole at or about a particular minute, but at no other time. A watchman, going his rounds during the night in a ware- house or public building, presses in one of the pins every quarter of an hour (or at any other interval that may be adopted in the mechanism of the clock). If, next morning, any one of the pins is found sticking out, it shows that the watchman was negligent of his duty at a par- ticular hour ; and the apparatus hence becomes a tell-tale. Ajire alarum and a floating alannn have also been invented. Alfoata, one of the kinds of mixed or artificial White Metals (which see). Albumen, so far as manufactur- ing processes are concerned, is best represented by white of egg. Its usefulness consists chiefly in this that when caused to coagulate by contact with certain acids and other substances, it entangles various impurities in the coagulated scum, and thereby clarifies liquids, such as syrups, &c. Alcohol, or pure spirit, is never known in the arts ; it is always diluted or deteriorated in some way or other. The nearest approach to purity is in spirit of 'wine. The article DISTILLATION will show how all alcoholic liquids are artificially produced; and under HYDROMETER is explained the mode of estimating the strength of spirits, by determin- ing the ratio of water to alcohol. Alder. Some of the uses to which alder -wood is applied in the arts are noticed under TIMBER. Ale. The differences between ale and beer are noticed under BEER AND ALE ; BREWING. Alembic is a small apparatus for distilling, serving the same purpose as the still. (See DISTILLING.) Alkalies. Many of these chemical substances play an important part in the manufacturing arts, chiefly in neutralising acids and forming salts >y combining with them. The true alkalies (potash, soda, and ammo- nia), and the alkaline earths (lime and magnesia), are briefly noticed under those headings. Alkanet is one of the vegetable substances included under DYE DRUGS. It gives a reddish colour :o perfumery, furniture oil, imita- ive port wine, &c., as well as to dyes. Alloy is a sort of generic name ALL ALU for a mixture of any two metals ; but sometimes it is applied only to the baser or inferior of the two, such as copper in standard gold and silver ; while, if mercury be one of the two, the mixture is more usually called an amalgam. Some metals are too brittle, some too soft, to be of much use in their pure or simple state ; but there are scores of combina- tions of them, two and two, which present various serviceable quali- ties ; and all such combinations form alloys. Sometimes three or even four metals form an alloy. In type metal the qualities of a soft, mal- leable metal (lead), and of a hard, brittle metal (antimony), are com- bined to produce a useful alloy that will possess properties depending on the proportions of the ingre- dients. The various alloys of lead and tin, such as pewter, differ in quality from the same cause. Copper and tin produce bell metal, bronze, gun metal, and speculum metal; and it is noteworthy what great dif- ferences are observable in these alloys, according to the proportions between the two components, all other conditions being the same. The change even goes to this ex- tent, that an alloy becomes harder in proportion to the increase in the softer of the two metals. Copper and lead make pot metal or cock metal. Copper and zinc produce the various kinds of brass and yellow metal; copper, tin, and zinc, the brass for plugs, and for large bear- ings in machinery ; while copper, tin, zinc, and lead produce a metal suitable for pumps, &c., in the ratio of 80, 5, 7-5, and 7-5. That alloys are chemical combinations, and not merely mechanical mixtures, is shown by the fact that their specific gravity is seldom a mean between those of the components ; and that they are more fusible, or melt at a lower heat, than the most fusi- ble of the two components. The principal alloys will be found no- ticed under their proper names, and some others under the names of the simple metals. Alpaca is a beautiful wool ob- tained from an animal of the same name, allied to the llama kind. The wool is silken, lustrous, pliable, and elastic straighter and stronger than that of the sheep and lamb's wool. The supply is obtained mainly from South America attempts to accli- matise the animal in Australia and other countries not having hitherto been very successful. AJpaca is employed not for woollens, but for stuffs, unfelted or unmilled, such as those described under WORSTED MANUFACTURES. The finest alpaca mill in England is Saltaire, a vast establishment near Keighley, in Yorkshire. The import of alpaca in 1867 was 95o,ooolbs. Alum is a compound of alumina with sulphuric acid and some kind of alkali. Natural Alum. This is a kind of crystalline efflorescence on the surface of certain minerals, produced by the action of air and moisture during a long continuance of time. It may be scraped off in fine par- ticles. At the Hurlet Alum Mines, near Glasgow, there is much of this efflorescence to be seen on the roofs and wails of the various galleries and workings. Reduced Alum. Nume- rous kinds of alum stone, alum slate, and bituminous shale are made to yield up their alum by the application of heat and other processes. Alum stone is the chief source in Italy, alum shale near Whitby, and bituminous shale near Glasgow. The alum stone is broken in pieces, roasted over a wood fire, kept moistened till it falls to powder, boiled with water, and the water allowed to crystallise into the much-valued Roman alum. The alum slate is roasted over a coal fire, steeped and washed in water, and the water allowed to remain for many hours onTresh ore, to become saturated with sulphate of alumina. After boil- ing, the liquid first gives off crystals ALU ALU of sulphate of iron, and then, with a few other processes, crystals of alum. The crystals are poured into large wooden casks, and present them- selves as a large mass of alum when the staves of the cask are removed one by one. The bituminous shale, which often accompanies the coal- beds in our collieries, is steeped in water, left exposed to the air for some time, and the liquor boiled in large stone or brick vessels. Pot- ash, chloride of potassium, the refuse of soap-works, sulphate of ammonia, or the refuse of gas- works, is added to the hot liquor ; the liquor is cooled in separate vessels, and crystallised into alum. Chemical Alum. This is made by the artificial combination of the con- stituents. The alkali may be any one of three different kinds ; whence result potash alum, soda alum, and ammonia alum. The French pro- duce alum from clay by the follow- ing series of processes : The clay is well ground, mixed with sulphate of potash, made up into round balls, calcined in a furnace, exposed to the action of sulphuric acid vapour, and then to the air, steeped in water, and the liquor crystallised. By an- other method, 100 parts of clay are mixed with 50 sulphuric acid and 50 nitre. The mixture is distilled, and the residue left in the still becomes a source of alum. Various other modes have been patented for the production of this highly useful sub- stance. Circumstances have lately led to a gradual substitution of ammonia alum for potash alum in England ; chiefly the abundance and cheapness of the ammoniacal liquor which is a refuse at gas-works, but partly the greater richness of the alum itself. Spence's patent ammonia alum, largely made in Lancashire and Yorkshire, is thus produced. Bitu- minous shale is slowly calcined, boiled with sulphuric acid in large leaden pans, and the liquor run into another leaden pan, to which the vapour of boiled ammoniacal liquor is admitted. The solution is then cooled, and crystallises into ammonia alum. Pochin's alumi- nous cake a cheap substitute for alum in many manufactures is made by a peculiar treatment of China clay and sulphuric acid, without the addition of any other ingredients. Alum is largely employed in dye- ing and calico-printing, in making tawed leather, in dressing skins, in hardening and whitening tallow for candle-making, in making paste for paper-hangers, and size for paper- makers ; also to lessen the combusti- bility of wood and cloth, to aid in the filtration of water, in forming artists' lake colours, and in making bread. Alumina is an oxide of the metal aluminium, and is the basis of nearly all kinds of clay ; it occurs naturally in felspar and many other rocks, and can be obtained chemically from alum. When pure, alumina is a white powder, soft to the touch, in- sipid, insoluble in water and in most acids, very hard in its small particles, so purely white as to form a good basis for paints and colours, attracts moisture strongly, becomes plastic when mixed with water (this is a characteristic of the clay series gene- rally), gives the crimson tint to the colours called lakes, and forms a fine blue colour in combination with cobalt. The gems sapphire, orien- tal ruby, and topaz are nearly pure alumina in a crystalline state. In almost all clay, silica is present with alumina in various proportions. The most useful salt of alumina is the sulphate, for which see ALUM. Aluminium. Within a recent period the metal aluminium has become practically known to manu- facturers, instead of being limited to the laboratory of the scientific chemist. The metal was first iso- lated from alumina in 1845 by Wohler; and in 1854 Deville de- vised a mode of obtaining it sum- ALU AMA ciently cheaply to bring it within the range of manufacturing purposes. This process was an elaborate one, involving many successive opera- tions upon a mixture of alumina and charcoal, aided in various ways by chlorine gas, hydrogen, sodium, and other agents. Morin, Rose, Dick, Gerhard, and other chemists introduced improvements from time to time, which gradually lowered the price of the metal in the market, though there is little probability that it will ever be cheap. Before the im- proved processes were introduced, aluminium sold for as much as gold, weight for weight; from which standard the price lessened to 6os., 2OJ., 8.T., and4-y. per oz.; even at 4,5-. it is nearly as dear as silver, and there- fore only suited for use in special pur- poses. When prepared by any of the numerous plans now adopted, aluminium is a white metal, some- thing like zinc in colour and hard- ness ; it is only one-fourth as heavy as silver ; it is very sonorous, and seems likely to be useful for musical instru- ments ; in elasticity and tenacity it about equals silver ; it can be beaten out, either hot or cold, into very thin leaves, even so thin as 80 ^ 00 inch thick; it is easily drawn out into wire ; it can readily be polished by burnishing, and varied by a beautiful alternation of burnished and matt or dead surface; it undergoes no sensible alteration in air or in oxygen, even at a high temperature. Then, again, aluminium melts at a lower temperature than silver, and is on that account preferable for some manufacturing purposes ; it flows easily into moulds, whether of metal or sand ; if soiled by dust, it can be cleaned with india-rubber or soap and water; if made greasy, with benzine ; it can be soldered with an alloy of zinc, copper, and aluminium, having 80 to 90 per cent, of the first- named metal ; it forms alloys with iron, zinc, nickel, copper, and silver. The various properties of alumi- nium have already brought it into use for a number of purposes. It is used for bracelets, seals, combs, spectacle frames, penholders, pins, spoons, forks, drinking vessels, covers and tops of vessels, purse snaps, shirt studs, harness orna- ments, statuettes, candlesticks, can- delabras, telescopes, opera glasses, sextants, theodolites, small fractional weights, and numerous small articles. Its rank may now be said to be mid- way between the precious metals and the common metals. The mutual relations of aluminium and copper give origin to a remark- able alloy. Each gives hardness to the other ; and the compound, of a golden colour, takes a fine polish. The nearest approach to a true golden appearance, by a compound in which no gold exists, is made by copper alloyed with 5 or 10 per cent, of aluminium, deep and pale gold colours having their respective ratios. This alloy, under the names of aluminium bronze, and aluminium \ gold, seems likely to have an im- i portant future before it. An alloy | of 90 copper and 10 aluminium possesses remarkable malleability and strength. Amadou is a kind of fungus that grows upon many old trees. The sort chiefly known is that which acts as a kind of tinder under the influ- ence of sparks from flint and steel a use which the lucifer match has nearly thrown into oblivion in Eng- land. Amalgam ; Amalgamation. An amalgam is a compound of mercury with some other metal ; and amalgamation is the process whereby the union is effected. Many such amalgams may be easily formed ; and they are for the most part either soft or easily crumbled. With lead, mercury forms an I amalgam useful in silvering the in- sides of glass globes ; with gold, an amalgam which assists in the pro- cess of water-gilding or metal-gild- AMB ANC ing (see GILDING) ; with tin, an amalgam which constitutes the me- tallic back of a looking-glass or mirror (see SILVERING), and also an amalgam which facilitates the deposition of a thin brilliant coating of tin on the surface of iron, steel, and copper, called cold tinning ; with zinc, an amalgam useful as a protection for iron ships' bottoms ; \vith palladium, an amalgam em- ployed somewhat in the same way as that of zinc ; with zinc and tin together, an amalgam useful for coating electrical machines. Amal- gamation is strictly any mode of causing mercury to combine with other metals to form the amalgams here noticed ; but technically it usually means the separation of silver or gold from the ores in which those precious metals are usually found, mercury being the agent or instrument. As regards silver, for instance : sulphuret or other ore of silver is washed, ground, mixed with common salt, roasted, ground again, and mixed with mercury and iron. Various other substances being driven off, the silver and mercury unite ; and the mercury is finally driven off by distillation, leaving the silver isolated. A process nearly similar is employed for gold. (See further under GOLD and SILVER.) Amber is a gummy exudation from certain trees, supposed to be now ex- tinct. It is picked up in small, irre- gular pieces, mostly on the southern shores of the Baltic. Many of the* specimens have flies or small insects embedded in them, showing that the substances must once have been in a glutinous state. The working up of amber into necklaces, ear- rings, bracelets, mouth-pieces for meerschaum pipes, &c., is a deli- cate department of lapidary work, owing to the change in electrical condition when heated. Amber forms the basis of a very fine var- nish. As large pieces are most valu- able, the dealers sometimes cement small pieces together with a frau- dulent intent ; and sometimes copal, enclosing insects, is sold as amber. Ambergris, employed for its odoriferous qualities, is a substance found floating on the sea in the Indian Ocean, and supposed to be a product of the spermaceti whale. Amethyst. (See GEMS AND PRECIOUS STONES.) Ammonia, as an alkaline gas, enters either as an agent or as a product into many of the processes of chemical manufactures. Practi- cally it is now obtained chiefly from the gas-works ; it exists in the tar- water which ascends from the re- torts, and can be separated from it by the action of muriatic acid and slaked lime. Water, saturated with this gas, becomes liquid ammonia. With acids it forms numerous me- dical salts, one of which is sal am- moniac. A compound of ammonia, called spirit of hartshorn, is ob- tained by distilling hoofs, horns, and bones ; and various modes are occasionally adopted of obtaining ammonia and some of its com- pounds from blood, flesh, woollen rags, silk rags, hair, hide and leather scrapings, soot, camel's dung, guano, and peat. Gas refuse, however, is, as we have said, the chief and cheapest source. More than three million gallons of gas refuse are produced every year in the metro- polis alone ; and the ammonia con- tained in this is something enormous. Various examples of the usefulness of ammonia in the arts will be found under their proper headings. Ammoniac G-um. (See GUMS.) Anastatic Printing 1 . (See TRANSFER PRINTING.) Anchor Forging-. The diffei- ences in anchors, to the eye of a mariner, do not much concern us here. Regarded in a manufacturing point of view, anchors rank among the largest examples offorgings'm iron. The whole anchor, if of com- plete form, comprises the shank, ANC ANI fing, stock, arms, palms, flukes, and peak. If any part is wood, it is the stock or cross-piece, near one end of the shank, the arms being at the other end. Some anchors are 19 feet long, and weigh 94cwt. The Great Eastern has one nearly 120 cwt. Regarded as to modes of con- struction, Rodgers's anchor has a wooden core within a hollow iron shank ; Pering's has a shank of flat bars instead of solid iron ; Porter's has the arms pivoted to the shank, instead of being fixed ; Trotman's and Honiball's comprise a number of minor improvements ; Stuard's has only one arm, for certain pur- poses ; Kingston's is secured to the cable without the use of a ring; Lenox's is an improvement on the old anchor byincreasing the strength without increasing the weight or cost ; HaWs may be separated into two halves, and carried in two boats ; CotselVs has the arms removable; Hutchins's and Morgan's are sepa- rable into several pieces ; Hawkins's has no stock, but a revolving piece which enables both the flukes to enter the ground at one time. In the days before the steam ham- mer, the forging of a large anchor was considered a great work at the Government anchor smitheries, owing to the number of hands re- quired to wield the ponderous sledge- hammers ; but the steam hammer now expedites the process wonder- fully, and gives a more scientific aspect to the manufacture. (See HAMMER, STEAM.) Anchovy is very similar to Sar- dines (which see). Angrling Tackle. (See FISH- ING TACKLE.) Ang-ora Wool is the wool of a long-haired goat, and is employed in the Cashmere shawl manufac- ture. Aniline Colours, or Coal-tar Colours, are by far the most re- markable of all those which the dyer and calico-printer now employ, in being the most beautiful as to tint and lustre, and produced from one of the cheapest and most un- pleasant of substances coal-tar. At the time of the first Great Exhi- bition, in 1851, these colours were unknown ; at the time of the second, in 1862, they had come into fashion ; while at the Paris Exhibition, in 1867, they took place as a large and important item of manufactures. Among the gases which pass out from the retorts in gas-Arorks are numerous compounds of tar and ammonia; and these, by special modes of treatment, are made to yield aniline. Then numerous other processes convert this aniline into brilliant colouring substances. One is aniline purple, a beautiful bronze-like colour; another is ro- seine, a rich intense crimson ; a third is violine, belonging to the violet class ; a fourth is magenta, or fuchsine, a red or crimson of inde- scribable beauty. Other colours are bleu de Paris, a light blue ; emeral- dine, or aniline green, a green with an olive tint ; chinoline, a blue ranging in various shades, almost from violet to green ; azuline, sol- ferina, &c. In every one of these cases a chemical process of some- what elaborate character is required ; and thus, although the prices are gradually lowering, aniline colours are still somewhat costly. It is not merely the pure richness of the colours themselves ; there is a lustre or bloom which gives to them a peculiar charm. Silk and woollen goods take these dyes very readily ; cotton goods do not quite so readily, animal fibres appearing to assimi- late better than those of vegetable origin with these singular coal-tar colours. Animal Strength, as a moving power, is a matter of much im- portance in the early stages of the mechanical arts, though not so much so when air or water power, still less when steam power, becomes ANI available. English experimenters have been accustomed to make I Ib. the unit of weight, I foot the unit of height, and I mile the unit of distance, in measuring the power of a man in a working day of eight hours. The French experimenters use I kilogramme (== 2-2 Ibs.), I de- cimetre ( = 3-94 inches), and I kilo- metre (= o-6J miles) as units; and hence it is not always easy to com- pare the one set of experiments with the other. Tables are gradually being formed, showing the most useful ways in which human strength can be exerted in lifting, dragging, or pushing burdens ; walking up an incline ; ascending a ladder ; working with a rope and pulley ; lifting weights by hand ; carrying weights on the back ; lifting earth with a spade ; wheeling a barrow ; pushing and pulling horizontally; turning a winch ; raising and lower- ing vertically ; dragging a cart ; pushing a whim or gin ; wheeling a truck ; all these have been com- pared, and the results tabulated in reference to the most useful modes of applying the strength of men, and in some instances the strength of quadrupeds. Animal Substances useful in the arts will be found described in various parts of this volume. The ingenuity of man displays itself more and more in developing such uses, until there is now scarcely a scrap of any dead animal that is not rendered available for some purpose or other. The hides and skins yield leather, parchment, and vel- lum ; the cuttings and scrapings from them yield glue and size ; the hair, fur, and wool are available in tex- tile manufactures ; the fat and suet assume new forms in soap, candles, c. ; the intestines and membranes reappear as musical strings, gold- beater's skin, &c. ; the Hood is a clarifier and a dye ingredient ; the horns, tusks, teeth, and hoofs are used for handles, buttons, lanterns, ANN ornaments, &c., or are decomposed to yield colouring and chemical sub- stances ; the bones for similar uses, and for manure. The quills of birds are used for pens and for hair- pencils ; \hefeathers for ornaments and for bed -stuffing ; the eggs as a source of albumen for various ma- nufacturing purposes. The deni- zens of the deep yield oil, sper- maceti, whalebone, fin, &c. The winged insects yield silk, lac, co- chineal, and countless other sub- stances useful in the arts. Sponge, coral, shells, eggs, tortoiseshell, pearls, mother-of-pearl, ivory, bris- tles, are other substances which help to fill up the list of materials for manufactures derived from the animal kingdom. All parts of this volume supply illustrations of these varied uses. AnimS is one of the gum resins used for scenting pastils. Annealing- is a mode of giving a certain degree of hardness without brittleness to glass, earthenware, metals, and several other manufac- tured substances. Wherever heat is employed, such as in founding, forging, &c., the particles heated are apt to assume a certain brittle- ness or instability of arrangement ; the substances maybe hard enough, but not sufficiently tenacious to bear blows, bending, twisting, sharpen- ing, or other mechanical treatment to a sufficient degree. Most plans of annealing consist in a gradual heating followed by a gradual cool- ing; and the maximum heat imparted determines the kind or degree of annealing. Medals struck with a die, wire strained out by a draw-plate, boiler plates drawn out between rollers, and copper and brass articles under the hammer, all become brittle, and require annealing to give them the requisite toughness. The tempering of steel is one variety of annealing. (See, for illustrative examples, such articles as CUTLERY, GLASS MANUFACTURE, ENAMEL, ANN ARC PORCELATN, POTTERY , & C . ) Cll Hied iron and case-hardened iron or steel may be regarded as the antithesis of ' annealed or tempered metal. (See CASE-HARDENING.) Annihilator, Fire. (See FIRE EXTINCTION.) Anthracite is a very hard coal, j sometimes called glance coal and Hind coal ; it contains less hydrogen than any other hind, and therefore gives out very little flame. It is used for many of the same purposes as coke, and in burning lime and bricks. (See further under COAL.) Anti-friction Wheels are wheels interposed between moving surfaces in machinery, to lessen friction by converting a rubbing into a rolling contact. Antimony, a metal useful in many of the arts, is, when pure, la- mellar in structure, bluish white in colour, lustrous, very brittle, easily reducible to powder, fusible at a heat a little under redness, boils into vapour at a white heat, and burns with a white flame when strongly heated. It is found native in small quantity, but is mostly pro- duced by smelting some of the ores, chiefly the sulphuret. When quartz and other ingredients have been driven off by heat, the sulphuret be- j comes crude antimony ; and when | some of the sulphur has been dissi- | pated, the ore becomes crocus, glass \ of antimony, and liver of antimony, \ according to the proportion of sul- phur still remaining. A further application of heat gets rid of the rest of the sulphur, and then there re- mains the pure metal, or regulus of antimony. Antimony, by combining with other metals, forms many useful alloys more brittle than the compo- nent metals. Type metal is usually I antimony + 4 lead ; stereotype metal, I antimony -\- 6 lead ; union- plate metal, antimony and lead, with a little tin ; Britannia metal, 4 an- timony -|- 50 tin -\- i copper -\- I bismuth; and pewter (usually) I antimony -\- 12 tin. Various forms of antimony are useful in medicine, and have at times been employed as cosmetics. The chloride, forming butter of antimony, is sometimes used to assist in bronzing gun- barrels. Antiseptics. (See FOOD, PRE- SERVED.) Anvil, as one of the requisites of the smithy, is in itself nothing more than a pie'ce of iron, fitted to receive heavy blows without being either broken or dislodged. Practically, it exhibits very varied forms. Some are made of cast-iron, subject to a few finishing processes. Others are made of wrought-iron, several pieces being welded together at a white heat, and forged into form by blows from sledge-hammers. The best are faced with steel, hammered or welded when the steel is not quite so highly heated as the iron. The protuberant pieces of an anvil the chisel socket, the beak or conical end, &c. are usually welded on. Small anvils, for delicate work, are polished with emery and crocus. Anvils are placed sometimes upon solid timber, sometimes embedded in stone. Those underneath steam hammers are placed upon huge masses of foundation of enormous strength, otherwise the machine would soon beat itself into disorder. The greatest steam hammer in the world (at the Essen Steel Works, in Prussia) works upon an anvil weigh- ing 105 tons. Aquafortis. (See NITRATES; NITRIC ACID.) Aqua Regia was the alchemist's name for what is now called nitro- muriatic acid. It is useful in the arts, because it will do what neither nitric nor muriatic acid will do alone dissolve gold and platinum. Aquatint Engraving-. (See ENGRAVING.) Archil. The name of this colour- ing substance is more properly Or- c.hil (which see). ARC ii ARM Archimedean Screw. (See SCREW PROPELLER.) Argrand Lamp derived its fame from the ingenious mode in which its inventor, Aime Argand, allowed fresh air to get access to the flame. It does not, in effect, necessitate the employment of any particular form of lamp, nor any particular kind of oil or spirit ; it depends on the me- chanical construction of the burner. Argand made the lamp wick a cylinder, instead of a dense mass of cotton threads ; and he enclosed this wick between two metal cylin- ders, so that air can obtain access to the inside as well as the outside of the wick, and consequently of the flame. Argand's brother, about the same time, found that a glass chim- ney encircling the flame kept it steady, and aided the cylindrical wick in guiding currents of fresh air in the proper direction. By this means, the carbon from the oil, spirit or gas is all consumed ; there is little or no smell ; and the flame gives out a brighter light. The or- dinary ring-burner of .a gas-light is in effect an Argand burner. An Argand oil-lamp, in its complete form, also contains a provision for maintaining the level of the oil at the proper height in the burner. Armour Plates. Under IRON- CLADS the reason is given why ships of war are now often coated with very thick slabs of iron. These slabs or plates were at first reduced to shape by heavy blows adminis- tered by steam hammers ; but it is now considered that the iron ac- quires a tougher fibrous structure by rolling. It is a process of building up, the iron in the first instance being rolled into plates an inch or so in thickness. Several of these plates are cut into pieces, piled one on another, heated to a white heat, and rolled ; and this is done over and over again, not only to attain the requisite final thickness, but to thoroughly knead every fibre of iron throughout the whole structure. The rolling of some of these plates requires more powerful machinery than has ever before been brought to bear in iron-works, some of the rollers being solid cylinders of iron 8 feet long by 4 feet in diameter. At the International Exhibition of 1862 there was a rolled armour plate, made at the Atlas Works in Sheffield, 2i feet long, 4 feet wide, 6| inches thick, and weighing ioj tons ; also, a hammered armour plate, made at the Mersey Works near Liverpool, 22|-feetlong,6| wide, 5^ inches thick, and weighing 13 tons. At the Paris Exhibition (1867) there was a plate as much as 30 feet long. Sir John Brown and Co., at the Atlas Works, have made a pon- derous plate no less than 14 inches thick, weighing 30 tons. Nume- rous target experiments have been carried on, to determine whether one thick slab, or a slab made of many thin plates bolted together, possesses the most advantages ; but as regards ship armour, the one- slab system is that which is nearly always adopted. Armstrong- Gun is one of the remarkable class of modern ord- nance built up piecemeal, instead of being cast in a mould. Sir W. G. (at that time Mr.) Armstrong, while the Crimean war was raging in 1854, turned his attention to the manufacture of cannon ; and he per- fected a plan on which the British Government has spent several mil- lions sterling. The principle of an Armstrong gun is this : Flat bars of wrought-iron are twisted spirally round a steel bar or core, and welded ; another layer is twisted over this, but with a left-hand or opposite spiral, to break joint and increase strength ; a third layer fol- lows, perhaps a fourth or a fifth, according to the thickness of the gun each having a different spiral from the one underneath, but being welded to it. Pieces a yarcf or so ARN 12 ARS in length are made in this way, and two or more such pieces are welded end to end. Wrought-iron rings, shrunk on, bind all the pieces irre- sistibly together. The rod or core is taken out, the inner diameter of the gun is bored or turned with wonderful exactness, and rifled with a number of small grooves winding spirally round the interior. Some of the guns have a steel lining, but in others SirW. G. Armstrong depends on wrought-iron alone. The gun being breech -loading, mechanism strong, but exquisitely accurate, is needed to open and close the breech for the admission of the shot and the cleaning of the gun. The shot or shell, built up of many pieces, is especially adapted on the surface to the number of rifle grooves in the gun. Some of the Armstrong guns have fired shot to the distance of 10,000 yards and upwards. The largest Armstrong gun yet made is a 6oo-pounder a wonderful mass of built-up iron. Arnatto, or Anatto, is obtained from the South American arnatto tree (Bixa orellana). There is a reddish pulp surrounding the seeds of the tree ; and this pulp, steeped, fermented, and otherwise treated, yields arnatto, in the form of cakes or lumps 2 Ibs. or 3 Ibs. weight. Ar- natto is used in colouring cheese ; in dyeing and staining ; in making varnish ; in colouring ointments and plasters ; in mixing with chocolate ; and in many other ways. Aromatics, as chemical sub- stances possessing a pleasant aroma, are used partly in medicine, partly in cosmetics and other appendages to the toilet. They are obtained mostly by distillation from flowers, leaves, herbs, roots, &c. Aromatic Vinegrar is nothing but ordinary vinegar flavoured and scented with certain essential oils, such as those of cloves, lavender, and rosemary. Arrack is one of the numerous kinds of intoxicating beverages pro- duced by distillation. It is obtained in many tropical countries by dis- tilling from rice and from the juice of the palm tree ; indeed, it is sup- posed to be the most extensively consumed of any kind of alco- holic beverage. A little reaches England, to impart a peculiar fla- vour to punch. Arrow - root is a starch ob- tained from the roots of certain trees growing in the West Indies and other warm countries. The roots, taken up at a certain age, are washed, peeled, pulped, strained, dissolved in water, and allowed to settle, when the arrow-root collects as a powder like very fine flour. It is sent to Europe packed in cases, barrels, and boxes. It is largely used in making light puddings, and as a diet for children and invalids. Arsenic is associated in the minds of most persons with the idea of a poisonous powder; but it is really a shining metal. When pure, metallic arsenic is of a steel-grey colour, crystaljine texture, very brit- tle, about six times as heavy as water, sublimes without fusing at a dull red heat, gives off abundant vapours at a little below its boiling point, burns with a livid flame, and combines with the oxygen of the air at ordinary temperatures. It is usually obtained chemically by treat- ing white arsenic with black flux (nitre and tartar). The -white ar- senic, which forms so deadly a poi- son, is an oxide of the metal. It is made chiefly in Silesia, by a pro- cess in which, after carefully ap- plying heat to an ore called ar- senical pyrites, the oxide accumu- lates as a light powder on the walls of a condensing chamber. This is a very unhealthy trade, requiring great precautions among the work- men, in their diet and regimen as well as in their working operations. White arsenic, or arsenious acid, forms arsenites with cert ain bases,one ART ASB of which constitutes Scheele's green. The deadly poison is also used to some small extent in the lead-shot, the indigo, and the flint-glass ma- nufactures. Another combination of the metal with oxygen forms ar- senic acid, which, combined with potash, produces an agent useful in calico-printing. Arsenic forms but- ter of arsenic with chlorine ; realgar, white Indian fire (for pyrotechny), orpiment, and King's yellow with sulphur; and white tombac with cop- per. The poisonous effects of arsenic often make themselves apparent in the practical arts. The combination of white arsenic with copper, in Scheele's green, or Schweinfurth green, presents such a cool, durable, and cheerful colour as to tempt manufacturers to use it for colour- ing paper-hangings and other ar- ticles; but it is an unhealthy and even dangerous substance to em- ploy for such purposes. Artificial Flowers. (See FLOWERS, ARTIFICIAL.) Artificial Fuel. (See FUEL.) Artificial Limbs, to remedy some natural deficiency or accidental loss, are the results of very ingenious applications of mechanism, in which the surgeon and the metal-worker act in conjunction. Artificial teeth and artificial eyes, the one made of ivory and bone, the other of glass and enamels, call for the exercise of much skill ; but the " limbs " are of course arms and hands, legs and feet. Pare, Johnson, Baillif, Bigg, Peter- sen, Charriere, Huguier, Bechard, Gray, Palmer, Bly, and other surgical -instrument makers have gradually brought this art to great perfection. Many gallant naval and military officers, who have lost arms and legs in battle, have been sup- plied with artificial limbs so admi- rably constructed as to render nearly all the services which the natural limbs usually subserve. M. Roger, a celebrated French opera singer, having lost an arm by some accident, had an artificial substitute made by Petersen, with which he could draw his sword on the stage as readily- as any other stage hero. Underneath the leather covering and padding of these arms and legs is always an intricate assemblage of levers, springs, wheels, pivots, and other mechanical pieces, to enable the natural movements of the limbs to be more or less successfully imitated. Artificial Pearls. (See PEARLS.) Artificial Stone. (See CON- CRETE ; HYDRAULIC CEMENT ; STONE.) Artillery. (See ARMSTRONG GUN, CANNON FOUNDING, GUN, &c.) Arts, Useful. There never has been, and never can be, a direct line of separation between fine arts and itseful arts, because the tasteful element which constitutes fine art gives a direct additional value to the products of the useful arts ; while, on the other hand, there . is most un- questionably usefulness in many of the fine arts. For general purposes, however, it suffices to rank archi- tecture, sculpture, painting, and en- graving among those fine arts in which beauty is produced by -visual results; leaving poetry, music, oratory, the drama, &c., to take rank on other grounds. Useful arts speak for themselves ; every manu- facture is a useful art, from that of a lucifer match to that of a Great Eastern. Asbestos, or Amianthus, is a peculiar fibrous greenish-white mineral substance. The fibres are easily separated one from another ; and when spun and woven, they brm a cloth which may be passed through the fire without injury. Various minor uses have been found "or asbestos, of which the chief is, Derhaps, an incombustible wick for "amps ; but a fire-proof dress of this substance has occasionally been worn with remarkable impunity against scorching or injury. ASH 14 Ash. Some of the uses of the ash in building, engineering, and the mechanical arts are noticed under COACH MAKING, TIMBER, &c. Ashes, in general the remains of burned vegetables, are highly useful in many of the arts. They consist for the most part of the salts which had formed a portion of the living vege- table. Land plants are rich in salts of potash, silica, and lime ; marine plants in those of soda and iodine ; and manufacturing chemists have devised numerous modes of obtain- ing these salts from the ashes of the plants. (See KF.LP, POTASH, &c.) The ashes of peat and turf contain clay and sand, as well as alkaline salts. The ashes of wood produce a lye or alkaline liquor useful in washing and bleaching. In the animal world, the ashes of bones, hair, hoofs, &c., yield a great variety of chemical substances, espe- cially phosphate of lime. Our manufacturers import 100,000 cwt. of potash and pearlash alone an- nually. flishlar is a mode of arranging stones in masonry. The stones, instead of being left rough as in rubble, are nicely squared, and ap- plied in regular courses ; the sub- ordinate terms being tooled, polished, or rustic, according to the mode in which the surface is treated. (See MASONRY.) Asphaltum is one of the many lands of bitumen, or pitch, sup- posed (like coal) to have had a vegetable origin. It is found natu- rally in Trinidad, Asia Minor, South America, and other places; and it can be obtained artificially from coal-tar. It is nearly black in colour, has a pitchy odour, burns readily with a smoky flame, and dissolves easily in naphtha and oil of turpen- tine. The uses of asphaltum (as- phalt, asphalte) are numerous. It is used for pitching ships' bottoms ; for heating the retorts of gas-works ; for giving a protective coating to ASS rough wood-work ; for making a kind of black varnish ; and as a pavement for streets and roads. When employed for the last-named purpose, the asphaltum is heated ; sand, gravel, and pounded limestone are added ; and the hot mixture is spread out as a layer on the ground. Road engineers employed this sub- stance in London a few years ago as a substitute for stone, but now it is almost wholly abandoned. As- phaltum has been usefully employed to keep out damp between the bricks and the overlying earth of the Metropolitan or Underground Rail- way. Assaying- is a mode of ascer- taining what proportion of gold or silver there is in an alloy of those metals. When an alloy of (say) silver is melted, the inferior metals become oxidised, and can be re- moved as a kind of scale. The assay or cupel furnace is a small upright stove, having within it a waggon-like earthen vessel called a muffle, closed at all parts except one end, and a few slits in the top and side. Small crucibles called cupels are placed in the muffle, which shields them from contact with the fuel in the furnace. The cupels are small cups, made of some substance that will not be now used for this purpose. (See HAT MANUFACTURE.) Beech. The useful qualities of this wood are noticed under TIM- BER. The mast, or nut, yields beech oil, and an oil-cake nutritious for cattle. Beer and Ale. These favourite beverages are nearly always made from corn or grain, but sometimes, as in the case of spruce beer, from othei parts of vegetables. Barley seems to be best suited for the purpose, and indeed beer at one time used to be called barley wine. According to the degree in which barley is malted, it becomes pale, amber, or brown malt ; and these differences gave rise to the distinction between beer and ale. Thus, pale malt pro- duces ale, while brown produces beer; and it has become customary in London to give the names of beer, porter, and stout (somewhat indefi- nitely, it must be admitted) to the dark liquor, leaving the name of ale to all those of lighter colour. In countiy districts, however, this rule is by no means generally followed beer being the good or strong, ale the inferior or weak. It thus re- sults, as a matter of fact, that the distinction between beer and ale is not a definite one, being different in different districts. So far as concerns London, there is pale malt in ale, and brown malt in beer, and there is morehop in ale than in beer adul- terations always excepted. When genuine, London porter has qualities which no provincial or foreign brewer has ever succeeded in equalling; but it lends itself sadly to various modes of unscrupulous adulteration. A new kind called cooper, a mixture of porter and stout, has recently come into vogue in London. At Burton- on-Trent ale is brewed in enormous quantities, classified into strong, mild, bitter, and pale the strong having most malt, and the bitter BEE BEL most hops. The breweries of Messrs. Bass and Messrs. Allsopp are among the largest establishments in the world. Scotch ale has a mild fia- vour and a pale colour, due chiefly to peculiarities in the process of fer- menting. Dublin has acquired fame for a peculiarly powerful and black beer, stout, which is made by Messrs. Guinness on a very large scale. Our exports of all kinds of beer and ale in 1867 amounted to 520,000 barrels. For the practical processes see BREWING; also HOPS and MALT- ING. Beer Engine is the small but highly-finished pumping apparatus used in public -houses for drawing up beer and ale from the cellar below. Some of them are very in- geniously constructed ; one handle governs two pumps, leading down to two casks ; and by a slight adjust- ment of the handle, liquor can be drawn from either cask alone, or from both at one time. Bees' Wax. Of the two pro- ducts of the bee most useful to man, one is noticed elsewhere. (See HONEY.) The other, wax, is the principal material employed by the industrious insect in building up the honeycomb, from which it is ob- tained by pressing, beating, melting, straining, washing, and cooling down to the condition of a cake. For some purposes the wax is bleached. Bees'-wax is used in a variety of ways in the arts, especially for making the large altar-candles burned in Roman Catholic churches. Beet-root Spirit. As sugar may always be converted into spirit, and as beet-root yields sugar, beet- spirit distilleries have been esta- blished in England. Hitherto, how- ever, they have not been commer- cially successful, and the enterprise must be regarded as a failure. Beet-root Sugar. Under SUGAR it is explained that beet-root is only one among a large number of vege- table substances from which sugar may be obtained. The roots, when taken up, are washed and rasped into a pulp ; the pulp is squeezed in presses ; the expressed juice is clari- fied, filtered, and boiled; and the production of sugar from the syrup is managed in some such way as that from the sugar-cane. (See SUGAR MANUFACTURE.) Beet sugar is not so sweetening as cane sugar ; but as the beet will grow in climates not hot enough for the cane, the manufacture of beet sugar is becoming important on the continent of Europe. In the season 1866-7 there were more than 500,000 tons of this sugar made in Europe, chiefly in France and Germany, in about one thousand factories. In a very favourable year an acre will yield 20 tons of beet-root ; while 12 tons of root will yield I ton of sugar, or about 3,500 Ibs. of sugar for an acre of land ; but the average of seasons and processes more frequently ranges from 1,000 to 2,000 Ibs. Bell. Bell metal is a mixture of copper and tin, usually 75 to 80 per cent, of the former. As a specialty, silver is sometimes thrown into the melting furnace. Steel is the metal of some modern bells, but this is exceptional. Some of the bells on the continent of Europe are of vast size. The bells at Olmiitz, Rouen, and Vienna weigh nearly 18 tons each. The great bell at Moscow, 21 feet high and about the same in diameter, weighs 193 tons; and another bell in the same city weighs 80 tons ; the Chinese bell at Pekin 54 tons. The Canadians have a bell at Montreal weighing 13 tons. In England, " Big Ben," at Westminster, weighs 14 tons ; "Great Peter," at York, II tons; " Great Tom," at Lincoln, 5^ tons ; and the great bell at St. Paul's, about 5 tons. Bell Founding-. Large church bells are cast in pits. Wooden templets, edged with metal, give form to the sand and clay which de- BEL termine the inner and outer curves of the bell ; and great care is shown in maintaining the width of the space with which the thickness of the metal is to correspond. The other processes are nearly like those described in CANNON FOUNDING, CASTING AND FOUNDING, and CYLINDER CASTING. Bellows. Some of the early bas- reliefs and paintings show that del- lows, to excite a flame by blowing air into a fire, were known in ancient times. The simplest form was that of two shallow boxes, the one inverted over the other, and joined together at one end ; the alternate raising and lowering of the upper box drew air into the intermediate space, and expelled it forcibly through a tube. The Chinese have a mode of propelling air through a wooden tube by a kind of piston. The familiar bellows, with two flat boards hinged at one end, elastic leather sides, a valve in the bottom board to admit air, and a nozzle to expel it, have been known in Europe for two or three centuries. Patent bellows have a revolving handle, which permits a continuous blast to be maintained. (See further under BLAST; BLOWING MA- CHINE; FORGE; VENTILATION.) Beng-al Light, used in military evolutions, as a signal at sea, and as a firework in pyrotechny, is com- posed of nitre 6, sulphur 2, and sulphuret of antimony I. When ignited, this mixture gives forth a vivid and brilliant light of a bluish tinge : hence the additional name of blue-light, Benjamin, Benzoin. The names benzoin, benzile, benzoile, benzoyle, benzole, benzine, benzoline, &c., are often used so vaguely that it is not easy to know which of them belong to the coal-tar series of substances. Benzoin is the dried milky gum or juice of the benzoin or benjamin tree : being very fragrant, especially when burned, it is used in per- 24 BER fumery, pastils, and incense. A tincture prepared from it constitutes Friar's balsam, useful in healing wounds and cuts, and is also one of the substances used in making court plaster. Benzoic acid, is obtained from the same source as benzoin. Benzile is one among many sub- stances obtained from benzoin by chemical treatmentwith chlorine and other agents ; it is a tasteless white solid. Benzole and benzoline are limpid colourless liquids, obtained from coal-tar naphtha ; they are now much used as substitutes for oil and spirit in lamps, and as solvents of india-rubber, gutta percha, and wax. Berlin Iron Ornaments. When Prussia was struggling with the first Napoleon, about 1809, the patriotic people sent in their gold and silver plate to the government, to recruit an exhausted treasury. The acknow- ledgment for these gifts was in the form of small iron crosses, rings, crowns, &c., each bearing the in- scription, Ichgab Gold um Eisen ("I gave gold for iron "). The trinkets were made in Berlin, and many of them are treasured up as honourable heir-looms in Prussian families. The factoiy has since been maintained for other purposes to make brooches, busts, statuettes, bas-reliefs, rosettes, medallions, and other articles. A very fine kind of iron is selected ; and the moulds are made of a peculiai mixture of sand and clay. So minute are some of the castings that 10,000 of them go to make up I lb., and the selling price is nearly 10,000 times that of the iron in its crude state. Berries. To notice all the berries useful in what may be called the chemical arts would be no easy matter, they are so numerous. They are, as a general rule, fleshy fruits, with the seeds immersed in the pulp. Many of them are employed ii flavouring gin, liqueurs, cordials, and British or sweet wines. Beryl. (See GEMS AND PRK cious STONES.) BES BIR Bessemer Steel. This is pro- duced in a way different from those noticed under STEEL MANUFAC- TURE. In the Bessemer process, molten pig-iron is decarbonised by sending a current of air through it. The fundamental idea is old, but Mr. Bessemer's application of it is new; and from 1855 to 1868 con- tinual improvements were made, leading to a large and important de- velopment of steel manufacture. The change is chiefly effected in a vessel called the converter, which can be closed in on all sides, and made to oscillate on trunnions ; it is made of wrought-iron, but is lined with a composition of fire-brick and ground stone : there are tuyere holes at cer- tain places to allow a blast of air to be driven in. To commence the ope- rations, 3 or 4 tons of good pig-iron are melted in a separate furnace, and poured into the converter through an opening adjusted for that purpose. Here a continuous blast, at a pres- sure of 15 Ibs. to the square inch, is forced right through the whole body of molten iron for a quarter of an hour or more. The blast is then shut off, a small quantity of another kind of iron thrown into the converter, and the blast renewed for a few mi- nutes. The object to attain in all this is to burn away some of the car- bon in the iron by means of the oxygen driven in with the blast ; the choice of iron and the duration of the blast are arranged according to the extent wished to be given to this de- carburation. When ready, the metal is poured out into an immense ladle, and thence into ingot moulds. The trunnions on the converter and the ladle facilitate the oscillating move- ments necessary for filling and emp- tying ; and either steam power or hydraulic power is employed. The convulsion going on within the body of the converter is tremendous ; the molten iron, liquid as water, is dashed violently about by the force with which tlu- blast drives through it ; the heat, flame, and sparks are intense, and the whole apparatus trembles with the vibration. Ac- cording to the length of time during which the current is continued, more or less of the carbon is burned away ; and thus any intermediate grade between iron and steel may be pro- duced. Bessemer iron, Bessemer steel, steel-iron, iron-steel, and half- steel are all significant terms, denot- ing kinds of steel saleable at different prices, and applicable to different purposes. Bessemer-steel works are now established at Sheffield, Crewe, Essen, and many other places. The system is becoming one of great value, owing to the fact just men- tioned, that any intermediate grade between pure iron and pure steel may be produced at pleasure. Beton. (See CONCRETE.) Bice is the name of two colours used by artists, and consisting chiefly of carburet of copper. Blue bice is sometimes called mountain blue, Hamburg blue, and mineral blue. Green bice has also the names of Hungarian green, malachite green, emerald green, and mountain green. Biddery-ware is the name given to certain ornamental articles made in India of an alloy consisting of copper, lead, tin, and zinc. The articles are often beautifully en- graved, and the surface is treated with a mixture of salt, saltpetre, sal am- moniac, and blue vitriol. Billon, employed in some parts of Germany for coin, is an alloy of silver and copper, with the copper preponderating ; it is useful as a sub- stitute for copper, in being less heavy, but is not liked at the English Mint, partly on account of being easily counterfeited. Binnacle, on shipboard, is a kind of box containing the compass, and a lamp to illuminate it at night, with an opening at the side through which the compass-card can be seen. Birch. (See TIMBER.) The bark is largely used for tanning, and its BIR BIS stringy fibres for matting, cordage, &c. : by distillation, birch oil is ob- tained from it. Birch wine is made in some countries from the sap. Bird-lime is a gelatinous sub- stance obtained from the middle bark of the holly or mistletoe by steeping, boiling, straining, and eva- porating. Being very adhesive, it is employed by the bird-catcher to en- tangle the feet of his prey at some selected spot ; and in India it is used to destroy insects. Bird's Eye. (See TOBACCO MANUFACTURE.) Biscuit. In the making of china- ware and the better kinds of pot- tery, the name of biscuit is given to the articles before they are glazed. (See PORCELAIN and POTTERY.) Biscuit Baking-. A biscuit, as a flat cake of unleavened bread, is the English representative of a kind of bread used nearly all over the world, and almost from the earliest times. The manufacture of ship biscuits, as earned on at some of the steam bakeries, such as those at the Government Arsenals, is the largest branch of this trade. The flour is emptied out of the sacks, through a hopper, into the mixing troughs ; water is then added ; revolving arms speedily mix up the two ingredients ; the mixture flows out upon a table, where iron rollers knead it into a flat layer of dough ; cutting stampers descend and cut this layer into bis- cuits, either circular or hexagonal ; the biscuits travel along a revolving apron and enter an oven ; they ad- vance through the oven very slowly, and emerge at the other end hot, brown, and well baked. No hand touches the flour or the dough from first to last. A little bran and a little salt are usually added to the wheaten flour. In regard to all the other kinds of biscuits, the manu- facturing operations are on a less complete scale, but the ingredients employed are for the most part more choice in character. Captain's, "water, soft, yeast, buttered, Aber nethy, Jamaica, coffee, Oliver's, Reading, Cheltenham, spiced, Vic- toria, arrow-root, pearl, and nume- rous other kinds are flavoured more or less with butter, yeast, milk, sugar, spice, caraway, carbonate of am- monia, essences, &c. Many of these are made light and spongy, and almost all are baked with very little brownness of colour. There are several large establishments where such biscuits are made on an exten- sive scale; notably those of Peek and Frean at Rotherhithe, Huntley and Palmer at Reading, Carr at Carlisle, Harrison at Liverpool, and Slight at Edinburgh. In these bakeries the machinery employed is of a very complete and efficient kind. Bismuth is one of the minor metals in relation to its practical uses. When pure, it is brilliant, white with a slight tinge of red, about 9f times the weight of water, melts at about 510 Fahr., crystal- lises in cooling, transmits heat more slowly than most other metals, and is volatile at a high temperature. It is one of the few substances which ex- pand when passing from the molten to the solid state, as water does when changing into ice ; and this property gives rise to some of the rather limited applications of bis- muth to useful purposes. Bismuth is obtained in Saxony, from an ore in which it is found combined with oxygen, arsenic, and sulphur, by processes of smelting and refining. With nitric acid bismuth forms pearl -white, used as a cosmetic, as a flux for melting enamel, and as a vehicle for various metallic colours ; slightly modified, it is used also in gilding and in medicine. An alloy of bismuth with lead and tin melts at a singularly low temperature. (See FUSIBLE METAL.) With tin, bismuth forms a sonorous alloy suit- able for bells. Bistre is a brown pigment useful for water-colour drawings ; it is BIT BLA made from the soot of various kinds of burnt wood. Bittern. (See SALT MANUFAC- TURE.) Bitters. Chamomile, angelica, and other plants, by steeping and simmering, are made to yield pun- gent stimulant liquids called bitters, useful in medicine, &c. Bitumen, properly speaking, is mostly found in connection with coal, some kinds of which are much more bituminous than others, the richest in this substance being best fitted for gas-making. Shale and limestone are sometimes called bituminous ; the former when deeply impregnated with bitumen, the latterwhen merely discoloured by it. A peculiar mi- neral, called elastic bitumen or mineral caoutchouc,- is almost as elastic and flexible as india-rubber. (See also ASPHALTUM.) Blackband is one of the richest veins of ironstone, found chiefly in Scotland. Its chief constituent is carbonate of iron, of which about one-fourth in weight is pure metal. (See IRON MANUFACTURE.) Black Flux, useful in facilitating the melting of metallic ores, is a fine black powder, made by highly heating and charring cream of tartar or tartrate of potash. The metal potassium can be obtained from it by a careful series of processes. Blacking:. Every blacking-maker professes to have a favourite recipe of his own for making this useful liquid; but the ingredients usually comprise some land of lamp or bone black, sperm or other oil, molasses or sugar, vinegar, sulphuric acid, and water. The paste blacking is nearly like the liquid in ingredients, except in having less water. There is one firm of long standing, that of Messrs. Day and Martin, by whom blacking is made in enormous quan- tities. Black-lead is a very inappro- priate name for plumbago, seeing that it contains no lead whatever. Plumbago, called also graphite, is a carburet of iron, with an excess of carbon, and small portions of alu- mina, silica, and lime. It is found in small masses in the primary rocks of Cumberland and a few other dis- tricts. As plumbago is very intract- able in the fire, it is used, either alone or mixed with clay, as a mate- rial for crucibles. When pounded it is employed as a lubricant for machinery; as a coating for sub- stances which are to be electrotyped ; and as a glittering black polishing material for grates, fenders, railings, &c. Its chief use, however, is for black-lead pencils. The mineral being very scarce, the black-lead mine of Borrowdale, near Derwent- water, is of high value. Black-lead Pencils. In the usual way of making these service- able little implements, thin cedar boards are cut into small rods, in each of which a groove is cut by a small circular saw, just the size to receive a slip of black-lead, which has itself been cut from a slab of the mineral ; after which another rod of cedar is glued on, to cover the black- lead. Sometimes the pencil is round, sometimes square ; and in one form one half slides out from the other. Pure black-lead is not often used ; clay or black chalk is generally mixed with the dust or powder of the mineral into a paste, and then dried and hardened. The mixture is not only cheaper, but it allows of different degrees of hardness being given to the pencils. The making of black-lead pencils was one of the trades practically exemplified at the International Exhibition, 1862. Black Pigments are made of beech- wood black, ivory-black, cork- black, lamp-black, and some other substances of analogous origin. Black dyes are noticed under DYE- ING. Bladders are prepared for use by a very dirty and disagreeable pro- cess for jar and bottle covers. &c. BLA 28 BLA Besides the home manufacture, we import many hundred thousands annually. Blanket is a special product of the worsted or long-wool manufac- ture, in which the fibre is used in great quantities, to produce a thick and warm material. The processes of fabrication belong to the same class as those described in WOR- STED MANUFACTURE. Our exports of blanketing and baize in 1867 amounted to 4,500,000 yards. Blast. Every year the use of the hot blast in the iron manufacture is gaining the mastery more and more over the cold; but the mechanical ac- tion is pretty much the same in both. The hearth (see BLAST FURNACE) is pierced at the side with holes, in which are inserted the nozzles or tuyeres of the blast pipes. The tuyeres are made of cast-iron ; and to enable them to bear the intense heat to which they are exposed, they are made hollow or double, and cold water is allowed to circulate between. The tuyeres are fixtures, and act as funnels into which the nozzles of the pipes are inserted. The air comes from a large cast-iron cylin- drical blowing machine, furnished with an air-tight piston worked by a steam-engine. The cylinder is closed at top and bottom, but has various openings in the sides. When the piston is pressed down, the air below it is condensed, and forced into a side chamber; the partial vacuum thus produced causes fresh air to rush through a valve into the upper part of the cylinder. The up- ward movement of the piston pro- duces a similar result, by a careful adjustment of the several valves ; and thus the machine is double- acting. From the chamber the com- pressed air is forced into pipes, which convey it to the tuyere-holes on three sides of the hearth. If the steam power be sufficiently great, two cylinders are provided to one blowing machine, so as to make the action more continuous. One of the great blast cylinders in South Wales is 112 inches diameter by 100 inches high ; the piston makes 13 strokes a minute, and at that rate drives out no less than 13,000 cubic feet of air per minute. It is seldom, however, that the cylinder is large enough for more than 3,000 to 4,000 feet ; and even at this rate the quan- tity of air is 8 to 10 tons weight per hour. The usual average pressure of the air is 2\ to 3 Ibs. per square inch ; but blowing machines of im- proved construction raise it to 3^ Ibs., by the use of a smaller cylinder and piston worked with vastly-increased velocity. (See further under HOT BLAST.) Blast Furnace. When iron ore has been roasted and prepared for the process of smelting, the metal is extracted from it by the heat of a blast furnace. These furnaces are sometimes square in form, sometimes circular. The up- per part, called the case or body, is usually lined with a double skin of fire-brick, with the intermediate space filled up with fire-resisting sand or scoria? ; while the exterior is built up of masonry or strong brick-work. The body of the fur- nace is surmounted by a cylindrical chimney at a part called the throat; and the side of the chimney has a doorway, through which the ore, coal, and lime are thrown in. Be- low the body is a conical space, narrowing greatly towards the bot- tom, called the boshes ; and below the boshes is a nearly quadrangular space forming the hearth, ending in a receptacle called the crucible. The sides of the hearth are pierced with holes to receive the nozzles or tuyeres of the blast pipes. The blast furnaces vary from 30 to 80 feet in height ; but the usual height is 45 or 50 feet. Furnaces for the hot blast are wider at the top than those for cold. Some of the great furnaces at Dowlais and Cyfarthfa BLA BLE (South Wales) have an internal ca- pacity of 7,000 cubic feet, produce 600 tons of iron per week, and often contain 150 tons of ignited material at one time. The average yield in Staffordshire is 230 tons per week. By what means an intense heat is maintained in these fur- naces is explained under BLAST and HOT BLAST ; while the relations be- tween the whole routine of processes are shown under IRON MANUFAC- TURE. Blasting:. If the excavation of coal and metallic ore in mines were left wholly to the pick and shovel, the progress would be so slow as greatly to increase the cost of work- ing. The operations are on this account aided by blasting with gun- powder, which consists in loosen- ing large masses of rock at one time, more easily grappled with than when in situ. The miners, with a borer or juniper about 2 feet long, having a sharp Gteel edge at one end, make a hole in the rock (usually horizontal) by repeated blows of the jumper. A scraper draws out the pulverised stone from this hole. The hole is charged with gun- powder, having a copper needle or wire running through it. The rest of the hole is filled or tamped with clay, well rammed in with a tamp- ing bar. The needle is drawn out, leaving a kind of touch-hole. A train of powder is laid, a slow or quick match is applied, the ignition and explosion take place, and a large mass of rock is loosened. Under some circumstances a blast- ing cartridge and a safety fuse are employed, to lessen the danger of the operation. In a few exceptional instances the hole is eaten in by acids, instead of being formed me'- chanically; and, in some of the German mines, the rock is loosened by the direct action of fire, billets and faggots of firewood being heaped up and burned in certain parts of the mine. A formidable substitute for gunpowder is now coming into use (see NITRO-&LY- CERINE) for blasting mines, quarries, and tunnels. (See also, for still an- other agent, ELECTRO BLASTING.) Blasting- Oil. (See NITRO- GLYCERINE.) Bleaching-. This important pro- cess, though applied also to flax and other fibrous materials, has received its chief development in connec- tion with cotton. England used to send her woven cottons and linens to Holland, where, after boiling and washing, they were exposed to light and air, dew and sunshine, on the grass, which bleached, blanched, or decoloured them. Hence the name of Holland given to such linen, brown Holland being un- bleached linen. The discovery of the bleaching action of chlorine, however, about 1785, changed the whole course of operations, chloride of lime, or bleaching powder, being used as the great agent. As a dis- tinct branch of manufacture in Eng- land, bleaching now goes through three series of processes the re- moval of dirty, greasy, resinous, and starchy particles; the removal of colour ; and the glossing and fold- ing of the bleached cloth. Singe- ing. Woven cottons always exhibit a downy surface of minute fibres when they leave the loom. In order to remove these fibres, the cloth is passed over a singeing machine, which consists of a plate or cylinder of copper, kept nearly red-hot by gas jets underneath. The pieces of cloth are tacked temporarily toge- ther, and wound in an enormous length upon a roller, from which the cloth travels over the singeing cylin- der, and is received upon another roller. Soiling. The cloth is next boiled in a boiler called a keir, which is so constructed as to shower down a stream of liquid in the form of a spray on the cloth. The liquid is a hot solution of lime or some other alkaline agent, and the purpose ol BLE BLE the boiling is to remove dirt and grease. Washing. The washing machine has a water trough and two wooden squeezing rollers. The cloth passes continuously through the water in the trough between the rollers, which revolve 100 times a minute, and squeeze the cloth as it passes. The machine has, in many establishments, superseded the dash- ivheel formerly employed ; some of them are so large that they will wash 12,000 yards per hour. Che- micking. This, sometimes called scouring, is a second washing with smaller rollers, and some kind of acid in the water. It is, in fact, the bleaching process : chlorine, de- veloped from the chloride of lime steeped in the liquid, removes the colours from the cloth. Squeez- ing. After the cloth is thoroughly bleached, the greater part of the liquid is expelled from it by the squeezing machine one of the many varieties in which the cloth is passed between two smooth rollers, and pressed as it passes. Drying. The cloth passes over a series of steam- heated cylinders in the drying ma- chine, becoming quite dry before it leaves the last of them, although not smooth. Mangling. If the cloth is to be printed for printed muslins, chintzes, &c. it goes to the print-works after drying ; but if it is to be sold as calico or other white cloth, it requires a few finish- ing processes, of which mangling is one. The cloth passes through a cistern of water, and is then dragged between two rollers, which flatten and equalise the threads. Starch- ing. When flattened and equalised in surface, the cloth, wound upon a cylinder, passes through the starch- ing machine, which has a roller dipping into a trough of starch, and other rollers to press the superfluous starch out of the cloth. Flour paste, sometimes weighted with ground porcelain clay, and sometimes tinted with a little blue, is the composition here employed. Calendering. It is not all white goods that require to have a gloss given to them; but when such is the case, the calender- ing or glazing machine is employed. (See CALENDERING.) Making-up. Lastly (that is, unless the dyeing or printing is to be immediately done in the same establishment), the cloth is passed through a machine in which rollers are placed at definite distances apart, so as to form a self- measuring apparatus ; and then the cloth is packed into bales or other parcels, according to the market to which it is to be sent. Some of the great bleaching- works of Lancashire and Glasgow can bleach and finish I,OOO to 2,000 pieces of calico in one day. The bleaching and finishing establishment which furnishes Mr. Cola with his estimate for a mode- rate but efficient plant, supplies the following items : There being i chemicking or bleaching machine, this requires 2 pairs of squeezers, but one each of all the other machines ; these, with appendages of every description, ,640; steam power, boiler, and mill-gearing, /66o; or ^1,300 for the bleach- ing department. Then, for the finishing, the mangles, spreading rollers, squeezing cylinder, starch- ing, stretching, damping, calender- ing machines, &c., together with steam-engine boilers, mill-gearing, and hydraulic press, ^3,700, or ,5,000 with the bleaching plant. Such an establishment is adequate to bleaching 2,500 pieces of 20 yards each in a week. Other processes of bleaching are noticed in the arti- cles relating to the manufacture of Candles, Paper, Silk, Straw Plait, Woollens, &c. Bleaching- Powder. Towards the close of the last century, Mr. Tennant, of Glasgow, discovered that a saturated solution of chloride of lime would effectually bleach cot- ton and linen ; but he afterwards found that a more convenient form BLE BLO of this agent would be 'lime im- pregnated with chlorine. This chloride of lime, or bleaching powder, has ever since been the chief substance employed in bleach- ing. In order to make it, dry lime is spread out on long shallow trays ; several of these trays are placed one over another, a small distance apart, in a stone chamber which can be made air-tight. In a large vessel near at hand, common salt, sulphuric acid, and black oxide of manganese are mixed in certain proportions : the chemical action which ensues be- tween them leads to the evolution of chlorine gas. This gas passes into a leaden chamber containing water, and thence through leaden pipes into the stone chamber. Here the gas combines chemically with the lime, forming chloride of lime. The lime continues dry all the time a very convenient form for practical use. The quantity of bleaching powder now made annually is some- thing enormous. The chief seats of the manufacture are Glasgow, New- castle-on-Tyne, and Lancashire. A cheaper bleaching powder, made of some of the magnesian salts, is (1 868) coming into use on the Con- tinent. Bleak. (See PEARLS, ARTI- FICIAL.) Blende is a name given to many minerals, consisting chiefly of sul- phurets of metals. Black Jack, cin- nabar, realgar, red antimony , orpi- ment, and red silver are among these sulphurets. Blind, Printing: for. It is an invaluable solace for blind persons that means have been invented for enabling them to read. The words and letters wet felt with the fingers. The type is impressed by a sort of embossing, appearing in relief on one side of the paper, and in intaglio on the other. Whether the alpha- betical letters are Roman, Italic, Script, Gothic, or Egyptian in form, or whether new symbols altogether are invented, the actual printing on the paper is always by embossing. Unfortunately, the managers of Blind Asylums differ in their usages in this matter, insomuch that a blind person can only read the books which are printed in the form adopted at one or a few of such places. A universal alphabet for the blind, agreed upon by all teachers, would be a great boon. Many persons ad- vocate an alphabet of dots, each let- ter being represented by a particu- lar arrangement of the dots. What- ever system is adopted, the types are cast in metal, and the sheets of paper are printed by a very easy kind of typography, seeing that no ink is wanted. The systems in use are those with Roman capitals, small capitals with serrated edges, capitals and small letters combined, Roman letters slightly modified, and others invented by Lucas, Frere, Moon, and Braille. A complete volume in any of these systems is necessarily very costly, the New Testament costing from 2 to $. Blister Steel is one of the inter- mediate stages in the progress from iron. ( S ee STEEL MANUFACTURE. ) Block Machinery. A ship's block, or tackle-block, with its shell, sheaves, and other parts, being a curious curved mass of wood, it occurred to the elder Brunei, about the begin- ning of the present century, that it ought to be within the power of steam -worked machinery to fashion these articles. Accordingly, by a due exercise of his remarkable in- genuity, he devised the exquisite machinery which began to work in 1808. The block passes through several beautiful machines in suc- cession : (i), A straight cross-cut- ting saw cuts up elm to the proper lengths ; (2), a circular cross-cutting saw similarly prepares smallerpieces ; (3), a reciprocating ripping saw cuts these pieces to the proximate length and breadth of the block ; (4), a circular ripping saw does the same BLO BLU thing for smaller sizes ; (5), a boring machine makes the perforations for the sheave-holes ; (6), a mortising machine cuts out the hollow cavity in the block; (7), a corner saw cuts off the angles of the block diagonally, but without rounding them ; (8), a shaping machine gives the general curvatures to the exterior; (9), a grooving machine makes the scores or grooves which are to take the ropes ; (10), a converting machine cuts off and roughly shapes the slices of lignum vitae to make the sheaves ; (n), a coaking engine forms the cavity at the centre of the sheave, to receive the bush and pins; (12), a drilling machine perfects this cavity ; (13), a facing lathe gives the exterior form to the sheave. The putting together of the shell, the sheave, and the pin is hand-work. Messrs. Maudslay made two com- plete sets of Brunei's machines one for Portsmouth dockyard, and one for Chatham. Brunei received 20, ooo in six years for his services in this matter ; but it was estimated that the Government saved much more than this amount in the first two years. Brunei's block ma- chinery undoubtedly established the principle of employing steam-worked machines instead of hand-tools in fashioning wood for carpentry, &c. (See WOOD-WORKING MA- CHINERY.) Block Tin. (See TIN.) Blood. The blood of the ox and a few other animals is used to some extent in the arts, for clarifying sugar, for making certain cements and coarse paints, tor making animal charcoal, for manure, and in Turkey- red dyeing. Blowing- Machine. Besides the simple apparatus described under BELLOWS, many other forms of blowing machine have been devised. Vaugharfs machine consists of two square boxes placed side by side, with a crank, a pipe, a piston, and other apparatus for producing a blast with" the boxes alternately. In another arrangement, two vertical cylinders, with weighted pistons worked from the beam of a steam- engine, cause air to be driven from the first to the second, and then ex- pelled with augmented force from the latter. On the Continent a blowing machine called a trompe is used, in which the pressure of a vertical column of water is made conducive to the production of a blast. In some of the blowing machines now made, the working of pistons by steam power causes an immense quantity of air to be forced through tubes. The prin- ciple of these powerful machines is treated under BLAST and HOT BLAST; the smith's bellows, of inter- mediate power, under FORGE ; and the revolving fans, which will con- dense as well as exhaust air, under VENTILATING FAN. The last- named are gradually superseding many forms of bello\vs and blast- apparatus, on account of the con- tinuous action produced. Blow-pipe is a small pipe for directing a blast of air into a flame, to increase the intensity of the heat. It is variously formed, but has always a mouth-piece to place between the lips. Much art is required to direct the blast of air from the lungs in a proper manner ; but when well managed this blast raises the tem- perature of a flame to a very high degree, thereby facilitating many of the processes in soldering jewellery, gold and silversmiths' work, enamels, glass-blowing, &c. A still more intense heat is produced by the oxy- hydrogen blow-pipe. Blubber. The relation which blubber bears to the other products of the whale is explained under WHALE OIL. Blue Pigments. Azure blue, Prussian blue, Brunswick blue, cerulean blue, blue copperas, indigo, litmus, cobalt blue, ultramarine, king's blue, Paris blue, royal blue, BLU 33 BOB Saxony blue, Thenard's blue, blue vitriol, are some among the chief kinds of blue pigments or paints derived partly from vegetable, but mostly from mineral sources. Most of the chief kinds are briefly noticed in this volume under their proper headings. Blunderbuss is a short but wide-bore musket, capable of taking in several shots at once. As a mili- tary weapon it is nearly superseded by the carbine. Boat Building: is a minor appli- cation of the shipwright's art. In nautical language, the long-boat, barge, launch, gig, pinnace, cutter, jolly-boat, yawl, belong to ships, as satellites do to planets ; but other forms of boat, independent in their use, are the coracle, wherry, skiff, wager boat, &c. Considered as articles of manufacture, these several kinds of boat present a general simi- larity of character, partaking in a smaller degree of the operations noticed under SHIP BUILDING. The increased use of Wood-working Machinery (which see) has led to the invention of Thompson's boat- building machines, which have to some extent come into operation. For certain differences in arrang- ing the side-planks of boats, see CLINCHER-BUILT. Boat, Life. (See LIFE BOAT.) Boat-lowering- Apparatus. Mr. Clifford has invented a very ingenious contrivance for quickly lowering ships' boats into the water. Not unfrequently escape from a sinking ship mainly depends on the celerity with which this lowering is effected. If the blocks and ropes are not well adjusted and quite ready for action, a capsizing of the boat is very likely to occur. Mr. Clifford so arranges his davits, ropes, blocks, lanyards, rings, &c., that one man can lower the boat after he has taken his seat in it ; nay, one man has even done this when eleven others were with him in the boat, and when the boat had to be lowered 40 feet from the ship's davits. Different contrivances for the same purpose have been devised by Kynaston, Wood, Rogers, and others ; but Clifford's has come most into use. Bobbin. This name is given to various small revolving bits of turned wood employed in the textile manu- factures for winding the rovings, yarns, threads, &c. The number of these always in use is prodigiously large ; and as they must be turned in a lathe, the trade of bobbin-turning is an extensive one. The most numerous are the bobbins on which sewing cotton and thread are wound for retail sale ; these have been esti- mated at 250,000,000 per annum in Great Britain alone, using up 40,000 tons of timber ! The bobbin lathe is a self-acting machine of con- siderable power, turning out ten or twelve gross per hour. Bobbins of metal are used in the making of machine lace. Bobbin Net. The hand-made or pillow-made lace (see LACE) must necessarily be a costly article, even at the lowest rate of earnings on the part of the workpeople, owing to the length of time neces- sary to produce it. But the intro- duction of machinery has wrought a wonderful change. Machine- made net, with or without a pat- tern, now makes a very near approach in beauty to the patient results of hand-work. There is another cause of cheapness : pillow lace is mostly made of flax, machine lace of cot- ton. Just about a century ago, one Hammond, a stocking-weaver at Nottingham, being out of work, and knowing that hand lace brought a high price, bethought him of trying whether he could imitate it by a modified action of his stocking frame ; he tried, and succeeded in in- venting the fin machine, for making a net in coarse imitation of Brussels ground. In 1784 was invented the BOB 34 warp frame, for making warp lace. In the closing year of the century was invented the bobbin frame, the forerunner of the bobbin-net ma- chines which have since achieved such famous results. At first the stocking-weavers kept this new branch of trade in their own hands ; but when steam power became ap- plied to the machines, when new contrivances improved the action of every part, and when new capital en- tered the field, then did the bobbin- net or machine-lace manufacture assume the distinct position which it has ever since maintained. It was in 1809 that Mr. Heathcote invented an improvement which virtually esta- blished bobbin net; and in 1816 steam power was first employed to work the machines. Lace nearly as good as that which had been wont to fetch five guineas a yard could now be made for is. 6d., or at least fairly imitated. Bobbin-net Manufacture. It is perhaps hardly possible to name a machine in use at the present day consisting of a greater number of parts, and involving more intricate movements than a full-sized steam- worked bobbin-net machine, espe- cially with the attached Jacquard apparatus for producing figured pat- terns. The mere technical names of parts furnishes quite a long list carriages, combs, bobbins, point- bars, needles, thread-beams, lace- beams, rollers, guide-bars, slit-plates, c. In principle, the thread that makes the bobbin net is supplied partly from bobbins, and partly from a warp. The bobbins are very peculiar, being delicately-shaped pieces of brass, so thin as to pass between the threads of the warp ; there are more than 1,000 such bob- bins in a large machine, and they swing, in a peculiar pendulum-like manner, to and fro between the warp threads, in such a way as to twist the weft round the warp Varieties of Net. Machine net, BOI like pillow lace, varies in the shape and size of the mesh, the thickness and compactness of the thread, and the degree of ornamentation applied to the ground ; hence there are numerous varieties in the market. Broad net is woven the whole width of the machine ; quillings, or nar- row strips, are made several at a time, side by side in the same ma- chine. In fancy net the pattern is often worked in with thicker gimp by the Jacquard Machine (which see) ; but sometimes the net is made plain, and flie pattern afterwards put in by hand. Lace-running is the name given to this net-embroidering by hand. Lace-mending is a spe- cial kind of needle-work to restore broken or torn meshes. The number of kinds of fabric now brought within the range of this branch of industry is increasing every year plain silk net, silk net lace, shawls, scarfs, flounces, trimming lace, blonde edgings, insertions, spotted net, plait net, curtains, bed-covers, blinds, flowered sprigs, imitation thread lace, purses, military sashes, &c. Besides bobbin-net machines, there are in use in the Notting- ham district the Leaver machine, straight-bolt machine, circular-bolt machine, traverse-warp machine, and twist machine. Bobbin net and lace to the value of ^470,000 were exported in 1867, after supplying home demand, which is always very large. Bog:. So far as the substance of bog has yet been brought to any use, a little concerning it will be found under PEAT. Bog oak is ob- tained from the roots and fallen trunks of trees buried in the bogs of Ireland. Bog-head Mineral. (SeePARAF- FINE.) Boiler. The boilers for steam- engines are made in many different forms globular, cylindrical, wag- gon-shaped, &c. They are mostly made of sheet-iron riveted, but BOI 35 sometimes of copper, which is much dearer in the first instance, but more durable. Some boilers are made with the fire inside, some at one end, while for rapid heating the surface is often exposed to a very large area of fire action. Loco- motive boilers have brass or copper tubes running from end to end, and well secured ; the heated air is thus completely surrounded by water, which becomes thereby speedily raised to the boiling point. Some boilers have double internal flues, so adjusted that the heat in one shall assist the combustion of the fuel in the other furnace. The fierceness of the heat is kept up in some boilers by a lofty chimney, in some by blast or blowing machines; while in the locomotive the waste steam is used to augment the draught up the short chimney or funnel. Most boilers iiave several appendages be- longing to them : a feed apparatus, to keep the boiler supplied with water; a water gauge, constructed in various ways, but always so as to show the height of the water in the boiler ; safety-valves, for admitting the air, and for giving the steam a self-acting power of escape when dangerously high; a man-hole to admit a workman to cleanse the interior, &c. The. bursting of steam boilers depends on many circum- stances besides bad workmanship and high pressure ; it still remains, as it has always been, a subject re- quiring very scientific investigation. Mr. Fairbairn, above all other engi- neers, has treated this important subject most fully in his various papers and essays. Boiling-. The effects produced upon liquids, and solids immersed in them, by boiling, are too varied to be even enumerated here ; but it is well to point out how much these effects are influenced by the density of the air in the interior of the vessel, as well as by the nature of the liquids themselves. In the or- BOL dinary state of the atmosphere water in an open vessel boils at 212 Fahr. On the top of a mountain, where the air is rarer, the boiling point is below 212 ; at the earth's surface, if the vessel is closed in, and a partial vacuum be formed, the boiling point is similarly less than 212. In a deep mine, or in a closed vessel with the air con- densed, it is higher than 212. What is called "one atmosphere" is the ordinary average pressure of the air, equal to about 15 Ibs. on the square inch. If the pressure be increased by artificial means to two atmo- spheres, water does not boil till it reaches a temperature of 234 ; four atmospheres, 294, &c. This pro- perty is taken advantage of in sugar- boiling, where, by having a partial vacuum in the boiler or vacuum- pan, the syrup boils at a much lower temperature than 212, to the production of certain important re- sults. (See SUGAR MANUFACTURE.) Every liquid has its own special boiling point. Salt water has a higher boiling point than fresh. Oil of turpentine and sulphuric acid are examples of- liquids having a higher boiling point than water, other circumstances being equal ; while the ethers and alcohols are lower. Slight changes, too, are due to the depth of the liquid in the vessel, the lowest portion being hotter than the highest during boil- ing. It is supposed that this fact has something to do with the flavour of the beer in the great porter breweries of London, where the boiling is effected in vessels of vast dimensions. Bois-durci, or hardened wood, is the name given by the French to a material manufactured by M. Latry. It consists of the sawdust of hard wood reduced to a fine powder, mixed with blood and other ingre- dients, and pressed into moulds, producing beautiful articles of va- rious kinds. Bole is a sort of greasy, earthy EOT. BOO slightly lustrous mineral, found in various trap and basaltic rocks. Several kinds are prepared into red and yellow pigments, useful in many of the manufacturing arts. Boletus is a kind of fungus or mushroom, one variety of which is noticed under AMADOU. Bolts. (See RIVETS ; SPIKES.) Bomb. The relation which a "bomb or bomb-shell bears to other hollow projectiles is briefly noticed under SHELL. The small war-ves- sels in which they are often used oelong to the class of mortar vessels. Bombazine is a speciality of Norwich manufacture, where the trade began, and has ever since centred. The fabric has a worsted weft combined with a silk warp ; and the quiet appearance of the surface rendered black bombazine at one time a favourite material for ladies' mourning. It has, however, been nearly superseded by para- matta, barathea, rep, merino, and other worsted or stuff goods. Bombyx is the scientific name for the silkworm. (See SILK.) Bonbons. (See CONFECTION- ERY.) Bone Black is made by burning or distilling bones in close retorts ; various gases are given off, and a black substance remains. Further processes convert this into bone- black, or animal charcoal, which is largely used as a deodorizer, a de- colourer, and for other purposes in the arts. Bone Manufactures. Phos- phate of lime supplies more than half the entire weight of bones ; and this gives rise to a particular use of bone to which we shall advert pre- sently. Teeth are, in their nature, something between bone and ivory. By various processes of boiling under pressure, all the gelatine can be got out of bones, forming a veritable bone soup. Bone is susceptible of being worked up into many useful forms by the mechanical processes of sawing, turning, stamping, drilling, &c., to make buttons, knife-handles, combs, tooth-brushes, &c. When distilled in retorts, bone becomes decomposed, and its elements re- composed to form sal ammoniac, lamp-black, animal charcoal, plate powder, and one of the constituents for tipping lucifer matches. Bones with any remains of fat upon them are bought by soap-makers, who get out all the fat by boiling. Scrap- ings, shavings, and sawdust of bone find a ready sale for making jellies. The largest use of bones is now in making manure. Plants take up and assimilate certain constituents of the soil ; animals eat these constituents in their food, and incorporate them in their bones. Hence it is found that the bones of animals restore to the soil some of the richness which had been taken from it. When the bones are crushed, ground to pow- der, and steeped for two or three days in dilute sulphuric acid, they are entirely dissolved, and may easily be mixed up with any powder of vegetable origin, such as charcoal, peat, sawdust, or mould. The enor- mous quantity of 1,700,000 cwt. of bones was imported in 1867 so much are the demands of our farmers in excess of the home supply. Bonnet, although a woman's head-covering in England, is a man's woollen cap or hat in Scotland. The Highland regiments wear bonnets of special kinds. The broad bonnet and the Glengarry are largely worn in Scotland ; they are very durable, and convenient from their flexibility. The manufacture is conducted on a considerable scale in Kilmarnock, Stewarton, and other towns. Bookbinding-. This useful and elegant art comprises a number of ingenious applications of leather, cloth, paper, and gold. Folding. Supposing a book to be bound in leather in medium style, the first process is to fold the sheets of BOO 37 BOO paper. The sheets are of various sizes, such as demy, medium, royal, imperial, &c. ; they are folded into pages of different shapes ; and there is a varying number of pages to each sheet. The name given to the size denotes the number of leaves, not of pages : thus, folio, 4^0., 8vo., I2mo., i6mo., 2^mo., $2mo , qSmo. There are certain marks put in by the printer, caUed signatures, to guide the folder. The folding is done on a flat table, by women, with the aid of a long paper-knife ; prac- tice enables them to do it with great exactness, and with a rapidity of 300 to 500 octavo sheets in an hour. Rolling. The sheets require to be rolled or pressed to make them smooth and compact. This com- pression used to be done by beating them in small clusters at a time with a hammer of 12 Ibs. or 14 Ibs. weight; but it is now better effected by a rolling-press. This consists of two smooth horizontal iron rollers, placed a small distance apart. The process is completed in a shorter time, it com- presses the sheets into a more com- pact mass, and makes them smoother than by hammering. Sometimes, however, the sheets are placed in an hydraulic press. Sewing. The sheets forming one volume, brought together in a mass, are fixed in a cutting-press, and saw-cuts made across the back edge to receive the bands or cords to which the sheets are to be sewed, and which aid in fastening the covers. The sewing-press then comes into use. This consists of a flat board or table, two wooden screws rising vertically from it, and a horizontal bar joining the tops of the screws. Cords or bands, from two to six or seven in number, are stretched vertically from the bar to the stand, and are kept tight by screw-nuts acting on the bar. The sheets are laid one by one flat on the table, and the sewer sews them t the cords, passing the needle in and out of the sheets and around the cords : by the mode of using a continuous thread, the sheets are sewed to each other as well as to the cords. Rounding. The back edge of the book receives a coating of glue and canvas to secure the stitching. By a dexterous application of a hammer and the fingers, the back edge, while still moist with glue, is made round or convex, and the front edge hollow or concave ; while a kind of groove or recess is made to receive the covers, one on each side. Edge- cutting. The edges are then cut smooth by a cutting-tool called a plough, which bears some resem- blance to a carpenter's plane. The squeezing of a press keeps the book together in a compact mass while this is being done. The concave edge is temporarily made flat during this cutting, but it springs back to its proper concavity afterwards. Binding. The covers of books are mostly made of millboard, cut to the proper sizes and shapes from large sheets. Holes are .made through them, corresponding to the cords or strings ; and the fastening of the covers to the book mostly depends on the cords, which are passed through the millboard and pasted. Covering. The covering with leather next ensues. This is done by pasting the leather to the covers ; but much delicate manipula- tion is needed to effect this neatly. The "hollow back" of a book is produced by the interposition of paper or cloth between the edge and the leather, in a way that enables the book to be opened without crinkling the back. Tool- ing and Lettering. Much of the adornment of a bound book is pro- duced by tooling. Numerous tools are employed in a heated s,tate, to be pressed heavily against the leather of the covers. If no gold is used, the tool produces a dark shining device, which is called blind tooling ; but in gold tooling BOO BOO leaf-gold is applied before the tools are used. In this latter case the gold is fixed to the leather by a coating of gold size, and the surplus gold is easily wiped off after the tooling. In blocking, the tools are fixed into a frame to form a device for the whole cover of a book ; and this is brought to bear by the force of a press ; it receives the name of gold blacking or blind blacking, ac- cording as gold is or is not used. The lettering of a bound book is but one special example of gold tooling, the tool being supplied with types instead of with an ornamental device. Edge Gilding, Edges of books are sometimes sprinkledvi'\\h colour ; sometimes marbled with a peculiar kind of parti-coloured device ; some- times coated with one particular colour, highly glazed, like the red- edged Bibles and Prayer-books now much in fashion. The more elegant kinds are gilt. To do this, the top, bottom, and front edges are scraped smooth with a piece of steel ; they are coated with a composition of red chalk and water ; this is wetted with white of egg and water; the leaf-gold is laid on ; and soon afterwards it is brilliantly polished by rubbing with a burnisher of agate or blood-stone. Other kinds of bookbinding re- quire modifications in many of these processes. A book in cloth boards does not receive so much pressing as one bound in leather. A boarded book usually has only two or three strips to which the sheets are sewed ; a bound book has more ; and some- times there are strips of vellum or parchment instead of strings. In india-rubber binding there is usu- ally no sewing, the back edges of the leaves being cemented together with liquid caoutchouc. Books in boards have seldom got the edges so completely cut as bound books. The cloth cover is attached to the boards to form a case before the latter is applied to a boarded book. Much of the cloth is woven and em- bossed expressly for bookbinders' use. The case is attached to the book mainly by pasting, and not by the aid of the strings or cords. The sprinkling of roan or sheep-bound school books is done in nearly the same way as that of the edges of leaves. In cloth binding, the cloth for each particular book is often passed between cylinders specially engraved with some particular de- vice ; in other cases, a heavy stamp- ing press imprints a particular de- vice on the cover after the cloth has been pasted on the millboard. Vellum binding, for account books, bears special relation to the substan- tial way in which the sheets are stitched to vellum bands, and the bands fastened to the covers or boards. Boot and Shoe Manufacture. This important branch of industry is mainly hand- work, but machinery is being more and more introduced in it every year. Hand Work. The various kinds of calf, cow, dog, kid, and other leathers are cut up into pieces with the aid of a knife shaped something like a cheese-cutter ; and then the making up of the pieces into boots and shoes is the work of per- sons who are rather minutely classi- fied into boot-closers, shoe-closers, shoe-men, boot-men, clickers, run- ners, blockers, welt-men, heel-men, binders, &c. ; waxed hempen thread with bristle ends being the mate- rial for sewing the stronger kinds. Machine Work. Machines have been invented to expedite many of the processes. M. Lefebre, of Paris, invented a machine for fasten- ing the sole and the welt by brass screws, made out of a continuous length of wire. Waite's clicking machine greatly expedites the cut- ting out and binding of the linings of boots and shoes ; while another machine by the same inventor mo- dels the instep pieces. ManselPs blocking apparatus expedites the process of blocking the uppers of BOR 39 EOT boots. Other inventions relate to the ventilating of the sides of boots by means of small pieces of metal ; the making of a substitute for shoe- leather by blocking leather-raspings and gutta percha into shape; the sewing with wire thread instead of hempen thread ; the making of cir- cular revolving heels ; the introduc- tion of an elastic waist between the sole and the heel, &c. These novelties have been attended with various degrees of success. The late Sir M. I. Brunei invented a beautiful set of machines for mak- ing army boots and shoes, but the system was beset by certain diffi- culties which checked its practical working. At Northampton and Stafford there are large establish- ments where ranges of sewing ma- chines are employed in boot and shoe making ; but it is in America that real factories for such work have been most successfully established. One machine will cut soles at the rate of sixty a minute ; another will trim and shape the heels at the same speed ; a third will split leather into two thicknesses, instead of paring it away with a knife. A machine for pegging boots and shoes, instead of sewing them, cuts the wire into pegs, presses the sole firmly against an iron last, guides a peg against the sole, presses it through the lea- ther with great force, and clinches it against the iron sole. 3,300,000 pairs of boots and shoes were ex- ported in 1867, our manufacture being greatly in excess of the home demand. Boracic Acid is obtained chiefly in a state of vapour issuing from a volcanic mountain in Tuscany. Re- servoirs or artificial lagoons are formed in the side of the mountain, to facilitate the collection, liquida- tion, and crystallising of the acid. 3,000,000 to 4,000,000 Ibs. are thus obtained annually. Boracic acid is used in making borax ; also as a flux, as a glaze, and to tip the wicks of candles which are to require no snuffing. Borax, a compound of boracic acid and soda, is largely used as a flux to assist in melting metallic oxides and alloys, and as an ingre- dient in enamels, artificial gems, mineral colours, pottery, glaze, &c. It may be artificially prepared from boracic acid and carbonate of soda ; and it is also found naturally, as a sort of saline deposit, on the shores of certain lakes and lagoons. Boring-, or the making of a cylin- drical cavity, presents itself under various forms in the mechanical arts, which will be found noticed under their proper headings ; such as CANNON FOUNDING ; MACHINE TOOLS; ROCK BORING; WOOD- WORKING MACHINERY, &c. Boron, one of the non-metallic elements, is a dark olive-coloured powder when in the uncrystallised state, but a kind of light-coloured diamond when crystallised. Its use in the arts is mostly when in a com- pound state, as borax, boracic acid, and the class of salts known as borates. Bottg-er or Bottig-er Ware. (See PORCELAIN.) Bottle Glass. Referring to GLASS MANUFACTURE for an ac- count of the general arrangements of a glass-house, we have here only to speak of them so far as they relate to the making of bottles. Flint- glass Bottles. These are made in brass moulds, formed of two upright pieces so hinged together as to be easily opened and closed. The work- man collects upon the end of his blowing tube sufficient of the glow- ing pasty glass to make a bottle of the required size. He manipulates the mass by a few dexterous move- ments, and then thrusts it down- wards into the open mould. Closing the two halves together by means of a string, he blows through the tube, and forces the glass into all the crevices and details of the interior, BOW in such a way as to give to the in- terior of the bottle nearly the same shape as the exterior. The string being loosened, the mould opens, and the bottle is easily taken out. Pressed Glass. A cheap and rapid mode of making bottles and other forms of glass is by pressing. The hot mass of glass is placed, not into a mould, but in a die, where it is immediately pressed by a matrix, stamp, or counter-die. This plan is not so much used for bottles as for some other articles, such as the imitation drops and icicles for chan- deliers, and for Defries's crystal illu- minations. Wine Bottles. By far the most important branch of this trade is the making of common green wine and beer bottles, a trade conducted on an immense scale near Newcastle and Sunder- land. The ingredients employed are usually very coarse and cheap. The bottles are sometimes made in an iron mould, but sometimes are blown, depending partly on the size and partly on the quality. Huge carboys for chemicals are expanded in a singular way : a little water is introduced through the tube ; this water breaks out into steam, and the steam swells the carboy. The almost incredible quantity of 700,000 cwt. of glass bottles was exported in 1867. Bow, in matters of archery, is no longer the important affair which it was before the invention of gun- powder. The cross-bow or arbalist was provided with springs, levers, stirrups, &c., and had power enough to shoot a bolt with considerable force. The long-bow was like that at present in use in shape, more rapid and convenient in action than the cross-bow. Yew is regarded as the best wood for bows ; after which, elm, ash, and hazel. Box Wood. (See TIMBER.) Braid ; Braiding: Machine. Braid, stay-laces, coach lace, up- holsterers' cord, and other textile 40 BRA goods of analogous kind are made in an ingenious machine, in which any number of threads, from three to thirty, are twisted one around another by revolving wheels, spin- dles, and other apparatus. It some- what resembles on a small scale Huddart's beautiful machine for rope-making. Bramah's Press. (See HY- DRAULIC PRESS.) Bran is the husk of corn grain. Pure meal or flour has the bran en- tirely removed by the processes car- ried on in the flour mill ; but " se- conds " or inferior qualities are a mixture of the two, especially exem- plified in what is known as brown bread. Bran is also used in dyeing and calico-printing, and as a food for cattle and horses. Brandy. Under DISTILLATION it is explained that spirits can be obtained from a large number of vegetable substances containing al- cohol, or the chemical elements of which alcohol consists. One of these kinds of spirit is brandy. It is made by distilling wine red wine for quantity, white for quali ty. From 10 to 15 gallons of brandy are ob- tained from loo gallons of wine. The finest brandy is made at Cognac, in France ; the next quality is made from Spanish and Portuguese wines ; a third quality is made from the husks and stalks of the grapes left by the wine manufacturer. The very strongest and finest brandy is about half alcohol and half water. Slight additions of burnt sugar, colour- ing matter, and fusel oil are usually made. British brandy^ so called, is not derived from the grape at all ; it is distilled from grain or malt in the first instance, and then doctored up with argol, French olives, burnt sugar, grains of paradise, catechu, and other substances, to imitate real brandy as closely as possible. Our imports of real or foreign brandy in 1867 amounted to 4,800,000 gallons. BRA BRA Brard's Process, as applied to stone, brick, tile, slate, concrete, &c., is not to render those sub- stances impervious to water, but to ascertain whether they are imper- vious or not. It is founded on the circumstance that water increases in bulk when frozen, and by that enlargement tends to disrupt any substance which may have absorbed it. M. Brard devised a mode of causing stone to absorb a solution of sulphate of soda, which expands in crystallising; the little crystals, whether visible to the eye or not, disintegrate the surface of the stone Among many kinds experimented on, some came to ruin very quickly ; while granite, marble, and compact limestone long resisted the ordeal. When tried upon bricks, the pro- cess showed that imperfect burning tenders them very weak under this treatment. Old Roman pottery and tiles bore the test well. Among cements, an old specimen made in a peculiar way of 2 parts lime and I sand resisted the trial better than most kinds of building stone. (See STONE.) Brass. This is perhaps the most useful of all the artificially-mixed metals. It consists of copper and zinc ; and as these two metals will mix in any proportion, there is prac- tically no limit to the different kinds of brass. 100 copper and 14 to 16 zinc make gilding metal for com- mon jewellery ; i oo copper and 20 zinc is the red sheet brass made in Germany ; 100 copper and 20 to 25 zinc, Bath metal, pinchbeck, Mann- heim gold, similar, and other yellow metals used for cheap ornamental purposes, in some instances as sub- stitutes for gold ; 100 copper and 36 to 40 zinc, Bristol brass, and brass that bears soldering; 100 copper and 50 zinc, the ordinary yel- low brass, the most generally useful of all ; loo copper and 56 zinc, Muntz's patent sheathing ; loo cop- per and 7 $ zinc, spelter solder, a useful solder for copper and iron, yellow metal ; 100 copper and 100 zinc, soft-spelter solder, used in sol- dering brass ; 100 copper and 100 zinc is also one of the extremes of Muntz's patent metal ; 100 copper and no zinc, patent mosaic gold. Others, less frequently made, con- tain much more zinc than copper. Brass Founding-. In old times brass was made, not by combining metallic copper with metallic zinc, but by using calamine, one of the ores of zinc. The calamine was roasted, ground, washed, and mixed with a little charcoal ; the mixture was put into crucibles, with alternate layers of small pieces of copper ; the crucibles, closed in temporarily, were embedded in charcoal in a furnace, and then heat was applied. In mo- dern times brass is sometimes simi- larly made from a mixture of copper and calamine ; but the furnaces are differently arranged, and the fuel is coke. After many hours, when the contents of the crucibles have be- come a molten mass, each crucible is taken out separately with tongs, the scum is removed, and the molten metal is poured into an iron mould. A more usual way, however, is to combine the copper directly with metallic zinc in the proportions re- quisite for each particular kind of brass. The furnace arrangements for the purpose are simple. Ingots of brass are melted to be cast and fashioned in various ways. If to form sheets or wire, the metal is cast into flat plates between two slabs of Cornish stone. Brass Manufactures. Heat and pressure are employed in various ways, in making both brass itself, and the various kinds of brass and yellow-metal articles. Muntz's metal is made by casting the copper and zinc into ingots, heating the com- pound to redness, and rolling out in a mill to make ships' sheathing, bolts, &c. Soft-spelter solder is made by pourin^ the .melted metals BRA 42 BRE into indented moulds, which yield small cubes about 2 Ibs. weight ; these are heated to redness on a charcoal fire, broken up on an anvil, and sifted. Articles made of brass, with 50 to 100 of zinc, such as candlesticks, &c., are first annealed, and then subjected to the surface processes of lacquering, &c. Brass made of from 25 to 50 zinc files and turns well, better than with a greater or a smaller proportion. The red- ness of the copper colour prevails up to IOO copper to 60 zinc, after which the whiteness of the zinc colour predominates in the tint. The brass is more and more fusible according to the proportion of zinc it contains. Many of the processes described under CASTING AND FOUNDING, ROLLING, STAMPING, &c., apply just as much to brass as to iron. About 50,000 cwt. of brass was exported in 1867. Brazil "Wood is the heart-wood of a small tree growing in Brazil. It yields a reddish-yellow liquor, very useful in dyeing, calico-printing, and red-ink making. About 1 1 ,000 cwt. of Brazil-wood was imported in 1867. It has lately been superseded in some degree by cam-wood. Brazing* ; Braziers' Work. Brazing, as one kind of soldering, is described under SOLDER ; SOL- DERING. Bread Making-. The first per- son who mixed the meal of grain into a dough, flattened it into a cake, and baked it on wood embers, was virtually a bread-maker the ad- dition of yeast or leaven being a subsidiary affair. Of course we know that such cakes were made and eaten by some of the earliest tribes, and that bread-making was thus one of the earliest of the arts. Wheaten bread, or loaf bread, is rendered light, porous, and easily digestible by fermenting, and is the modern representative of the lea- vened bread of old times. Sea biscuit, oat cakes, barley bannocks, rye cakes, &c., are examples of un- leavened bread. The Ingredients. Referring to FLOUR MILL for an account of the mode of producing the different kinds of flour, it will suffice here to say that bread of different fineness is made by using flour of different qualities. Omit- ting minor distinctions, wheaten bread is made of the best flour ; household, of the next best; and brown, of a mixture of kinds, in- cluding some of the bran, or husk. Nearly all English loaf bread is made of wheat, very little barley, oats, rye, or maize being so used. A portion of floui is mixed with warm water, yeast is added, and the mixture, called the sponge, is set aside in a warm place. The sponge gradually ferments, swells, heaves up, and gives off bubbles of carbonic acid gas. At a par- ticular stage this fermenting is stopped; the remaining flour and water are added. Usually, boiled and mashed potatoes are used with the flour, as also a little salt and alum. As to gypsum, chalk, pipe- clay, ground bones, and the like, there is no reason to believe that they are much used as adulterants. Kneading. The mixing and knead- ing the ingredients into dough in- volve very laborious processes ; for not only must all be thoroughly mixed, but much rolling and pres- sure are needed to produce a smooth and homogeneous substance. As the housewife finds a rolling-pin necessary in preparing dough for her pudding, so does the baker need somewhat similar aid in mak- ing dough for his bread. Baking. When the dough is thoroughly kneaded it is weighed out into portions, shaped into loaves, set aside to undergo a certain amount of fermentation, and then baked. The oven is usually a low-arched structure, 3 or 4 feet high in the middle, with a brick or stone floor, and an iron door in front. In the BRE BRE old days the oven was heated by shavings, and billets thrown into it, and then cleared out before the bread was put in ; but now there is usually a fireplace on one side, the hot air from which circulates round the oven and heats it. The loaves are introduced into the oven by means of a long-handled shovel called a peel, and placed nearly close together all over its brick or stone floor. They are removed in a similar way when baked. Hot-water ovens are now used in some bakeries, the hot water being made to circulate in pipes around the interior of the oven, the baking temperature being maintained at about 440 Fahr. In Neville's bakeries each oven is about 10 feet by 8, and 2 high ; it contains 400 feet of hot- water pipes, and a tell-tale alarum that rings when the oven becomes too hot. A bread oven introduced in France by M. Rolland has a revolving tiled floor, j so constructed that any part of the ' circumference can be brought in turn to the oven mouth, for facility in filling and emptying. A sack of flour yields about 90 4 Ib. loaves, or 360 Ibs. of bread, from 280 Ibs. of flour ; but some bakers manage, by a larger admixture of water, to obtain 92, 94, or even 96 loaves. Dauglish's Aerated Bread has no yeast or ferment in it ; carbonic acid is directly applied, instead of re- sulting from fermentation. While the dough is being worked by steam power in a strong iron globular vessel, carbonic acid is forced in. The result is, that when the loaf is baking, the gas expands, bursts in bubbles from the surface, and makes the bread light and porous by forc- ing its way through the dough. Medical men give a high character to this bread for purity and salubrity, while the manufacturing processes are simple, rapid, and economical. Many forms of bread are baked in tins, to give definite shape to the loaves ; but this does not alter the other characteristics of the bread. Ship bread is noticed under BIS- CUIT BAKING. Breaming- a ship is cleaning the outside of the hull after a long voyage, to remove the seaweed, shells, ooze, grass, &c., which al- ways accumulate, and which retard the progress as well as injure the timber and sheathing. The bottom being exposed, a fire of furze and fagots melts the pitch, and the scraping off of this pitch removes all the refuse. Breech Loaders. (See ARM- STRONG GUNS; CANNON FOUND- ING; SMALL ARMS.) Brewing-. In brewing, the starch of grain is converted into a kind of sugar ; this sugar gives character to a fermented liquor ; and the liquor receives a particular flavour by the addition of hops. The processes arrange themselves, therefore, ac- cording to the attainment of these several objects. Malting. In some country districts the brewer converts his own barley into malt ; but malt- ing and brewing are essentially dis- tinct processes. The object in view is to bring the substance of the grain into such a state that it will easily yield a soluble sweetish extract fitted for fermentation. (See MALT AND MALTING.) Grinding. When the malt reaches the brewer, it is crushed to a coarse powder. This crushing is sometimes done between horizon- tal millstones ; sometimes by steel mills, which act like coffee-mills ; and sometimes by case-hardened iron rollers. Mashing. The crushed malt falls into the mash tun, into water at a temperature of about 1 60 Fahr., which causes it to swell considerably. This action is con- tinued for a certain time, the liquid being agitated by revolving arms, until the water becomes sweet by extracting the saccharine matter from the malt. Boiling. The sweet liquor, or wort, is drawn off from the mash tun into a vessel called BRE 44 BRE the under-back. The malt under- goes a second mashing with a new supply of water; and the two infu- sions or worts are brought together in the under-back. A third mash- ing is sometimes made, to produce weak or small beer. It is calculated that if 13 quarters of malt be used for 1,500 gallons of beer when finished, 2,400 gallons of water are used in the mashing. In order to produce beer or ale of definite strength, the brewer mixes the dif- ferent worts accordingly. The proper mixture of worts is transferred from the under-back to the boiler, where it is boiled for some time, and the proper quantity of hops added. The hops are kept constantly stirred during the boiling. The wort be- comes concentrated, and also cleared by the separation of the mucilage and gluten which were in the malt. Kent and Sussex hops are preferred for porter and stout, but those of Worcestershire for ale : the propor- tion ranges from 2 Ibs. to 8 Ibs. of hops to I quarter of malt, according to the degree of bitterness required. Cooling. The wort Hows from the boiler into the hop-back, a ves- sel with a perforated bottom ; here the liquor flows through, while the spent hops are retained. It then passes to the cooler, which is either an extensive but shallow floor, where the liquor is exposed to currents of air, or else it is a series of pipes surrounded by cold water. Fermenting. The cooled liquor passes into a vessel of vast size called the fermenting tun; yeast is added (I gallon or so to ipo gallons of wort) ; frothy matter rises to the sur- face ; a slight hissing or effervescing sound is heard ; the froth deepens in colour from white to brownish yellow; and the whole mass is in fermenta- tion. Clearing. By fermenting, the wort converts a portion of its sugar into alcohol. By continuing the process, the alcohol would change to vinegar ; but as the brewer does not want this, he stops the process at a particular stage, and racks off the liquor into vessels called rounds. Here it gets rid of froth and carbonic- acid, becomes clarified, and now fairly earns the name of beer or ale. Storing. When quite finished, the beer is stored in vats of enormous dimensions, from which it is drawn ofFinto the butts or casks with which we are all familiar. Usually some liquid made with isinglass, called finings, is put into each cask to clarify the beer. In the brewing of ale some of the above-described processes are modified, but the general character is maintained. The sugar of the malt is partly converted into alcohol or spirit by the fermenting process ; but to so small an extent, that the strongest pale ale has only 10 per cent of alcohol, while the weakest table beer scarcely exceeds I per cent. Although brewing may be con- ducted on a very small scale, it prac- tically gives employment to some of the largest manufacturing establish- ments in the kingdom. The porter breweries in London, such as those of Barclay and Perkins, Truman and Hanbury, &c., are very vast, as are the ale breweries of Bass and Co., Allsopp andCo., &c., atBurton- on-Trent. Some years ago, Barclay and Perkins's brewery required 100,000 gallons of water per day ; there were 20 malt-bins, each as large as a three-storied house ; the malt use"d in a year was more than 100,000 quarters ; the brewing room was as large as Westminster Hall ; each cooling floor or tray was 10,000 square feet in area ; four fermenting tuns each held 50,000 gallons ; there were 300 rounds, each holding 300 gallons ; a tank, to keep the beer till transferred to the store vats, was large enough to float a barge ; there were 150 store vats, averaging 30,000 gallons each, some as much as 100,000 gallons ; the butts, pun- cheons, and vessels of various kinds BRI 45 BRI amounted to 70,000 in number; and 200 horses were employed in the drays which conveyed these casks to and from the several public- houses, docks, &c. Brick Laying expresses its own meaning at once. Kinds of Work. A wall may be any number of bricks in thickness ; and as English bricks are mostly of one size (9 x 4^ X 2\ inches), there may be many of these required to reach from front to back of the wall. Hence have arisen several modes of arrangement, in order to break joint ; that is, to avoid having one joint directly over another. The chief of these are the two following : In English bond there is one course of bricks laid length- wise of the wall, then one laid breadthwise, and so on. In Flemish bond, rows in the two directions are placed alternately in the same course. There are also herring bond and garden-wall bond. The bricks laid lengthwise are called stretchers ; those at right angles to them headers. In a nine-inch wall, or two bricks in width, equal to one in length, the alternation is easily managed. In a brick-and-a-half wall (14 inches), a two-brick wall, a two-and-a-half wall, &c., the stretchers and headers alternate in the way best suited to binding the whole mass together, and to some extent to present a pleasing exterior to the wall, especially where bricks of different colours are used. The Tools. The trowel, of well- tem- pered steel, will cut a brick as well as spread mortar. The hammer, with a sharp edge and a flat head, will dig out a brick to make a hole for a scaffold pole. The plumb- line and the level assist in pre- serving the vertical and horizontal truth of the brick wall. The measuring rod and the jointed rule are described in their names. The square gives a right angle. The jointer marks the joints. The com- passes draw circular curves for arches and the like. The rake has points for digging out old mortar between bricks. The line and line- pins afford the means of maintaining a straight line in the courses of brick - work. The bevel and the mould assist in shaping the bricks for arches. The tier saw cuts the curved section lines in a brick for arch-work. The rubbing stone and the float stone rub smooth the sur- face of curved bricks. The Work- ing. Taking the bricks and the mortar from an assistant labourer, the bricklayer spreads out his layer of mortar with a trowel, and arranges the bricks according to the kind of "bond" that may be required, bringing the mortar to the sides as well as to the top and bottom of each brick. When the wall is of superior strength, or intended to present a highly-finished surface, or when it has many curvatures and variations of surface, the skill of the experienced workman is then in re- quest. In the cutting and laying of gauged arches a distinct plant of tools is needed ; for each brick has to be shaped in accordance with its place in the curve, and the fitting of surface to surface must be very accurate. The building of founda- tions is also important work ; for no care in laying the bricks will suffice unless the earth beneath is made thoroughly hard and firm by means of rammed stones, piling, planking, or concrete. Still more necessary is this caution where the lower part of a building is an alter- nation of piers and arches ; for the pressure here necessarily varies greatly in different places. Inverted arches, as parts of the foundation, are often a necessary precaution. In strong walls for engineering work hoop-iron band is much used, bands of hoop being laid lengthwise between the courses. A thin and common wall, called brick-nogging, s made by placing wooden posts a yard apart, and filling up the spaces BRI 46 BRI between them with one row of bricks laid lengthwise ; the wall is there- fore only 4! inches thick. Groined arches, and the use of ornamental or coloured bricks, require the thick- ness of the layer of cement or mortar to be less than in ordinary walls, because more depends on the shape and accurate adjustment of the bricks themselves. The use of cement instead of mortar for high-class brickwork for engineering purposes is for the sake of increased strength. The arched tunnels for the Main Drainage of the Metropolis, exe- cuted for the Commissioners of Sewers under the control of Mr. Bazalgette, are considered to be among the finest examples of brick- work ever executed. The mortar used by the bricklayer is noticed under MORTAR and CEMENT. Brick Making:. In this, as in many other branches of manufac- ture, the articles are not only made more rapidly by machine than by hand, but they are more equable in quality and regular in appearance, owing to each one being an exact type of all the others. Hand-made Bricks, All the ancient bricks were made by hand. It is supposed that the Babylonian bricks were burned in a kiln ; that those which the Israelites made in Egypt were baked in the open air ; while in many countries they were merely sun- dried. The Romans were skilful brick-makers, as many ancient build- ings in England still testify. In making bricks by band in the present day, the clay is hrst tempered by long exposure to the air; and, if too stiff, sand or ashes are mixed with it. When kneaded to the proper consistency, it is separated into lumps, each large enough for one brick; the moulder dashes it into a wooden mould sprinkled with sand, and then removes the sides of the mould, leaving the brick on the bottom. The bricks, as made, are removed to a field, where they are dried in air and sunshine. Finally, they are burnt in clumps or in kilns. Machine-made Bricks. The ma- chines employed have been many in kind, due to differences of opi- nion among the inventors as to the best mode of achieving a particular result. The chief machines em- ployed are those of Gates, Clay- ton, Norton, and Tweeddale. The clay is spread out on the ground, and tempered with water until brought to a soft moist state, being turned over and over several times to expose new surfaces. It is thrown into a hopper, from which it falls between two crushing rollers, where any hard particles in it are thoroughly crushed. The crushed clay passes at once into a pug-mill, the revolv- ing arms or screw blades of which mix it up thoroughly into a homo- geneous and smooth mass. Wet Making. The clay thus prepared for the -wet process is forced through an aperture from the pug-mill into a horizontal clay-box ; from this it is forced in a continuous horizontal stream or band to a delivery table. At regular intervals a wire descends and cuts this band into separate bricks. The shape of the orifice in the clay-box determines the length and width of the brick, while the intervals in the descent of the wire determine the length. Dry Mak- ing. Although more labour is re- quired in grinding the materials, less drying and burning of the bricks are needed in the dry pro- cess than in the wet: the former is gradually coming more and more into use. The moulds for forming the bricks on the dry process are ranged round a circular revolving table. The machine is so placed that it discharges the prepared clay into two moulds at one time ; they travel on, and receive pressure by the action of a square piston or plunger, while two others are re- ceiving their quota of clay ; and so on. The bricks gradually rise out BRT of their moulds as the table revolves, and then pass over to a revolving endless band, which conveys them away. Burning. Some bricks re- quire to be dried before burning, but not all. In the ordinary brick-kilns there is a great loss of heat occa- sioned by the escape of hot air and smoke into the open air, no arrange- ments being made to economise it. To obviate this loss, Hoffmann, of Berlin, has invented a very im- proved kiln, capable of burning 25,000 bricks per day. The kiln, 160 feel in diameter, is a kind of tunnel or arched passage running in a circle. Round the outside are twenty-four doors, opened or closed as may be needed; these belong to twenty- four compartments, into which the ring-formed passage is divided ; and twenty-four flues lead from these compartments to a central chim- ney, with valves to cut off commu- nication. There are dampers, easily opened and closed, between the several compartments. The com- partments are rilled with newly- made bricks at different times, and are emptied at different times, in such a way that the heat, when it has done its work, travels on to other compartments, and is never wasted by escaping into the open air. The bricks do not travel round the ring, but the hot air does. Ven- tilating bricks and hollow bricks, having cavities of various sizes in or through them, are now much used. They are easily produced by modifications of the machinery. Messrs. Peto and Betts, during the progress of their works on the Chatham and Dover Railway, on one occasion made 200,000 bricks in a fortnight with one of Oates's machines ; but the average is usually 80,000 per week. Mr. Cola affords an idea of the cost of brick and tile machinery adequate to the produc- tion of a certain quantity of these articles. He sets down ^750 for the hoisting, grinding, pugging, 47 BRI moulding, cuf.tmgy and other appa- ratus necessary for making 12,000 bricks per day by the wet process ; and about an equal sum for steam- engine, boiler, and mill gearing of all kinds. Then, by the dry process, ^1,050 for the hoisting, grinding, and moulding apparatus necessary for making 14,000 bricks per day, with ^750 for steam machinery, &c. This would be .3,300 for the ap- paratus for a large permanent work. There is a second estimate for a portable series, according as the machines are to produce from 9,000 to 14,000 bricks per day. Brilliant. (See DIAMOND.) Brimstone, an old English word, is still retained in the Board of Trade Tables as the name for sulphur ; but manufacturers are gradually imitating scientific men in adopting this latter designation. Brine is the name often given to the salt in which beef or pork is being pickled, when liquefied by the juices of the meat ; but in Cheshire and AVorcestershire brine is simply the salt water pumped up from the brine springs. (See SALT MANU- FACTURE.) Bristles, used in brush-making and some other trades, are the strong glossy hairs growing on the back of the wild hog. The supply is ob- tained chiefly from Russia. They are of various colours ; but before being used for brush-making, they are sorted into Mack, grey, yellow, white, and lilies. The first four kinds are described by their names ; the lilies, silvery white in colour, are used for the best shaving and tooth brushes. Other things being equal, the thickest bristles are the most sought after, and fetch the highest price per pound. After sorting for colour, they are sorted for size. According to the nicety of the work to be done is the degree to which this sorting into colours and sizes is canied. Hogs reared in warm countries have hair somewhat too BRI 48 BRO soft to make good bristles. (See also BRUSH MAKING.) Bristles to the large amount of 2,400,000 Ibs. were imported in 1867. Britannia Metal is a compound of tin and antimony, in the pro- portion of about 10 to I, with some- times a little zinc and copper. It is almost as white and brilliant as silver, and is hence very largely employed in making coffee and tea- pots, hot-water jugs, soup tureens, gravy and vegetable dishes, wine coolers, liqueur stands and waiters, and other articles of table service appearing something like silver, but much cheaper. Britannia metal has remarkable ductility, which enables it to be worked by the process of metal-spinning; in which thin sheets are buniished or swaged down upon wooden moulds or other models, to the convexities and concavities of which they adapt themselves with remarkable facility. Alloys some- what similar to Britannia metal are noticed under WHITE METALS. British. Gum is the name given by calico-printers to a kind of gum made by charring or scorching potato starch. It is used as a cheap substitute for gum arabic in thicken- ing colours. Brocade is a woven silk on which a rich pattern is produced, super- added to the ordinary warp and weft threads. The Jacquard loom is now employed in weaving it. Bromine is one of the simple substances, in the nomenclature of scientific chemists. It is a deep red liquid, very heavy, very unpleasant in odour, and very poisonous. Some of the salts called bromides, pro- duced by the combination of bro- mine with the metals, are useful in the arts ; and bromine itself pos- sesses bleaching properties when mixed with water. Bronze, an alloy of copper and tin, is much used for bells, cannon, large statues, toothed wheels, and other castings, as well as for various kinds of stamped work. So greatly do the proportions vary, that while large bell bronze has only 3 parts of copper to i of tin, machinery bronze has often 10 to I. The usefulness of this alloy depends chiefly on its being very hard and very durable but it is also sonorous and pleasant in colour. Bronze Coinagre. No copper coins are now minted for English currency; they are superseded by bronze lighter, harder, and some- what more economical to the State. Bronze coins are made from bars 24 inches long, 0-375 inch thick, and varying in width, according to the coin, from 2\ to 3 inches. The fillets made by rolling are blanched in dilute acid. The blanks, stamped out of the fillets, require a careful annealing to enable them to bear the strike of the die. After many trials, the composition of the bronze was settled at 95 copper, 4 tin, and I zinc. The size and weight of the bronze coins are noticed under COINS, and the mechanical processes under COINING. Messrs. Heaton, of Birmingham, are largely engaged in this department of coining. Bronzing: is the coating of metal, wood, plaster, &c., with a compo- sition to give them the appearance of bronze. Various kinds are em- ployed. Gold powder touched over green paint ; German gold powder, made from leaf gold, silver, and copper ; mosaic gold, a powder ob- tained from a mixture of several metals all are used. Gun-barrels are bronzed (so called) by using acids to slightly corrode the sur- face of the iron, and give it a thin brownish oxide or rust, which is retained during the subsequent polishing, &c. Brown Figments, employed by painters, are derived from the mineral and vegetable kingdoms, but chiefly the former. They comprise umber, terra di Sienna, bistre, asphaltum, brown madder, and many others. BRTJ 49 BRU In glass and enamel painting, brown effects are often produced by sub- stances which are not brown in themselves, such as sulphates of some of the metals ; while in dyeing and calico-printing, arnatto, fustic, sumach, logwood, and alum are all employed in various ways to pro- duce browns. Brush. Brushes vary consider- ably in size and shape, in the soft- ness and length of the hairs or bristles, and in the mode in which the hairs are fixed in the handles or backs. Hair Pencils , used in minia- ture and water-colour painting, are small tufts of camel, badger, squirrel, or goat hair, inserted into an end either of a quill or of a tin tube, with a handle at the other end. Tools, the name given by the house- painter to the principal brushes used by him, are bundles of bristles tied by string to the thick end of a cleft handle. Stock Brushes, for whitewashing and distempering, may be likened to two or more tools placed side by side in a flat handle. Dusting Brushes^ have the thick end of the handle thrust directly into the tuft of bristles. Brooms have the hairs inserted in holes drilled in a stock of wood, to which a long handle is attached. Hearth brushes are neaily like brooms, ex- cept in the mode of fixing the handle. Drawn brushes, including hair, scrubbing, shoe, clothes, nail, and tooth brushes, have the hair or bristles drawn in a peculiar way through a flat back. Bottle brushes have a number of tufts of bristles fixed between two or three parallel wires in such a way as to enable the brush to wind about in all the curvatures of the interior of a bottle. Hat brushes are made of horse or goat's hair. Velvet brushes are made of a very fine variety of vege- table fibre. Whisks or carpet brooms are also made of vegetable fibre, but differing greatly in shape and size, and of larger fibre. Birch brooms are made of various kinds of coarse fibre or twig, such as birch, heath, or bass. Numerous other designations are given by brush- makers, such as Hack-lead, cloth, engine, brass finishers' , flue, har- ness, tube, carriage, furniture, horse, marking, graining, paste, spoke, tar, and varnish brushes. Brush Making*. Three exam- ples in the list, given in the fore- going article will suffice to illustrate the processes of manufacture. Drawn Brushes. The backs, stocks, or brush boards are made of various kinds of wood, according to the value of the brush to be made. Some are drilled completely through, no attempt being made to hide the bristles at the back (as in scrubbing brushes) ; whereas in others a veneer is applied for neatness of appear- ance (as in clothes brushes). The filling of the holes with hair or bristles is called drawing. The workers draw a tuft into each hole by means of a bit of copper wire, so tightly as to make it hold well there; and in some brushes the holes are made smaller near the back, to further tighten the hairs by a wedge-like jamming. The flag ends of the hairs are then cut to a general level. Some brushes, called penetrating, have the hairs left pur- posely unequal in length ; some have the surface of the wood so curved as to spread out the hairs like a fan. In the smaller and finer kinds, such as tooth brushes, the hairs are drawn with very thin wire sunk in narrow grooves on the back. Some brushes are trepanned ; that is, the tufts are drawn into the holes by means of threads passed through apertures cut in the edge of the brush ; the apertures are then plugged up, and nothing is left visible of the mode in which the hairs are inserted and retained. Brooms. The long brooms used for domestic purposes are made by boring holes to a proper depth in BUD BUL the wooden stock, giving some of them a splay to spread out the hairs somewhat. Bristles sufficient for one knot or tuft are taken in the hand, arranged evenly, dipped in melted pitch at one end, bound round with a thrum of string, dipped again in the pitch, and thrust into one of the holes with a sort of screw- ing motion. Hair Pencils. Small tufts of fine hair are collected, with the thick ends all in one direction. The tuft, with the thick end bound round firmly with strong thread, is thrust into the wide end of a softened and pliable quill. The swelling of the tuft at the part where the string is bound round helps to keep it in its place when the quill contracts by cooling. The size of the pencil thus made depends chiefly on the quill, whether it be from swan, turkey, goose, pigeon, or crow ; and much art is needed to insure that the fine ends of the hairs shall coalesce so as to form a tapering point. If the pencil is too large for any kind of quill to be used, a tin tube is employed in- stead. Bude Light, invented by Mr. Goldsworthy Gurney, is an extension of the principle introduced in the Argand lamp. There is not only one cylindrical ring of burners, but sometimes two, or even three, are placed concentrically; and, to pro- duce very powerful effects, the in- terior of the flame is fed with oxy- gen instead of common air. Buhl Workis a kind of inlaying, in which a metal ornament is inserted in wood in such a way that both may be brought to the same level. The art was carried to much per- fection by M. Buhl, a French ca- binet-maker in the time of Louis XIV. He usually employed a brass inlay upon tortoiseshell ; but the combination may be varied almost ad infinitum, the two substances being usually as thin as veneers. The two veneers are glued to the opposite sides of a piece of paper ; another piece of paper is glued on pasted to the outside of one of them i the device or pattern is drawn on the outside paper ; and then the two veneers are cut through and through, following the line or lines of the device. This cutting is effected with a buhl saw, very fine, narrow, and thin, and fixed in a bowed or arched frame. When the cutting is completed, the two layers can easily be separated ; and then two pieces of buhl- work may be produced, for each one serves as an inlay to the other. These inlays are placed as veneers to the surface of a cabinet, workbox, or any other article of ornamental furniture. Buhl, the cabinet-maker, mostly employed, as we have said, brass upon tor- toiseshell ; Reisner, a contemporary in the same trade, preferred tulip- wood upon some darker wood ; and this is the chief difference between buhl-work and reisner-work. But the same principle will apply to ivory, mother-of-pearl, and a large number of other substances. Cheap imitations of 'buhl-work are pro- duced by cutting out the veneer patterns with a stamping-press, in- stead of by sawing. Building Stone. (SeeMASONRY; QUARRY; STONE.) Bulkheads, in a ship, are the partitions of wood or iron which separate the interior into rooms or compartments. They are now often water-tight, being plates of iron so closely fastened to the sides, decks, beams, &c., as to render each com- partment water-tight, and therefore buoyant, in case of injury to other compartments by wreck, or by an enemy's shot. Bullets are mostly made of lead. In the old days they were simply cast in moulds ; but Mr. Napier has invented a machine to make them by compression, insuring much truer sphericity of form than before, and producing 40,000 bullets a day by one machine. Since the perfecting BUL BUT of the rifle, bullets have been made oblong, egg-shaped, or pointed at one end, and scrupulously formed at every part. The bullets for the Snider-Enfield rifles are now made by a beautiful machine, almost en- tirely automatic, and doubly as rapid in its action as Napier's. Bulrushes. (See RUSHES.) Buoy, as a sea-mark, is simply a floating object chained to the bed of a channel or river to prevent it from being driven away by winds and waves. But, though simple in purpose, it varies greatly in form and size. Some are made of wood, some of iron ; and one kind, the bell buoy, continues ringing a bell so long as there is any current under- neath it. The largest buoys ever constructed were those used in 1866 in the Atlantic, to mark critical points in the position of the Atlantic telegraph cable during the sub- mersion. Burgundy Pitch, employed in some of the arts, is made by boiling and straining the juices that exude from certain trees of the fir genus. Burnettising 1 is one of the modes adopted for preventing timber from decay, invented by Sir William Burnett. There is a strong solution of chloride of zinc, into which the timber is immersed. The same so- lution is applied to deodorise the bilge water which collects in ships' hulls. Butter Making- depends, for what little chemistry there is in it, on the peculiar nature of milk. Milk consisting of butter, caseine or cheese, a kind of sugar, and cer- tain salts, the process of churning is applied to separating the first- named from the other constituents. The Churn. The churn is made in many different ways, but always with an apparatus for keeping the milk (or rather cream) in a state of agitation. The common churn con- sists of an upright cask, with the sides either bellied or straight, and having a hole in the middle of the top. A long staff is placed upright in this hole, having at the bottom a round flat board with holes in it. By working this staff and board up and down, the liquid contents of the churn are kept in a state of con- stant agitation. The barrel churn is a cask which turns on a horizon- tal axis, and may have any kind of moving power applied to turn it. This rotation keeps the cream more effectually in agitation than the movement of the board in the com- mon churn. Many other kinds of churn were shown at the Interna- tional Exhibitions of 1862 and 1867. Butter Making. It is the process of cooling that separates the cream, and the churning that principally conduces to the separation of the butter from the other constituents. The milk, after being strained through a fine sieve, is poured into shallow pans, and exposed in a thin layer to the cooling influence of a draught of air. Cr,eam forms on the surface. There is a particular speed of agitation which is best for the churning. The cream separates into butter and butter-milk. The butter, repeatedly washed with fresh water, is worked about with the hands, or with a cloth, to expel the remainder of the butter-milk. Some butter, when made, is salted, and packed into casks or firkins of 561bs. each. Some is made up into rolls of a pound or two each. Some is stamped by carved wooden moulds into fanciful devices. Devonshire Cream, a spe- cies of butter, is the result of a certain degree of heat applied to milk. Epping, Cambridge, and Dorset have given their names to certain excellent kinds of butter. Dutch butter is very good ; Irish somewhat rank. Many kinds of butter receive an artificial colour- ing from Arnatto (which see). A good average milch cow, -well fed and kept, is estimated to produce BUT BUT about 200 Ibs. of butter in a year. An inferior kind, called whey but- ter, is made from the residue of cheese-making. Notwithstanding our large home produce, we im- ported 1,140,000 cwt. of butter in 1867. Button Manufacture. This con- stitutes one of the most important ' branches of industry at Birming- ham. Iron, steel, brass, copper, pewter, lead, gold, silver, horn, shell, pearl, tortoiseshell, ivory, bone, hoof, hair, silk, cotton, linen, gutta percha, india-rubber, amber, velvet, cloth, Florentine, glass, porcelain, enamel, jet, compressed earth, clay, gems, precious stones all are brought into requisition by the button-maker. As examples of two wholly distinct classes of but- tons, the gilt and the covered will suffice to give a general idea of the manufacture. Gilt Buttons. A kind of brass, copper with a little zinc, is the metal of which these buttons are usually made. The metal is rolled into thin sheets, cut into narrow strips, and stamped out into discs or blanks by the action of a fly-press. Each blank is rolled between two steel bars, to smooth and round the edge. Itis th en planished, or levelled on the surface, by smart blows from a steel hammer. The shanks are made of brass wire ; a machine cuts off a small piece, bends it ! into a kind of eye, and flattens or spreads out the two ends. One of these shanks is soldered to each blank by the aid of a little simple mechanism. -If the button is to have a plain face, the maker's name, &c., are stamped on the back by means of a die ; but if the face is also to be embossed, a die and counterdie are used, so as to stamp both surfaces at once. The buttons are scoured in a weak solu- tion of aquafortis, washed and dried, and then covered with a thin layer 01 gold. (See GILDING.) If the gold is only applied to the face, the buttons are known as tops ; but it to the back as well as the face, they become all-overs. The layer of gold is so excessively thin, that 3 grains are sometimes made to cover a gross of buttons ; and yet each button admits of being well burnished with an agate or bloodstone burnisher. Covered Buttons. A metal shell is stamped out of a piece of thin sheet iron ; a metal collet, or smaller disc, with a hole for the shank, is similarly stamped out ; a circular piece of silk, satin, Floren- tine, twill, mohair, cloth, or other textile material, is stamped out ; a circular padding is made of soft paper, silk, and thread ; and then all these pieces are brought to- gether in a wonderfully quick and effective way, by the aid of a peculiar die, a stamping-press, and certain punches and hollow tools. The shank, protruding through the hole in the collet, is not an eye of metal, but a tuft of soft material through which a needle and thread can be passed. The padding fills up the space between the metal face and the metal back. It would be im- possible even to enumerate all the processes employed in this manu- facture. Almost every manipula- tion known in the arts is rendered available by theBirmingham button- makers, according to the substances employed casting, stamping, trac- ing, embossing, drilling, piercing, carving, welding, soldering, grind- ing, smoothing, burnishing, gilding, silvering, tinning, plating, electro- plating, japanning, chasing, engrav- ing all are brought into requisition. Buttress, as a matter of mere building, is a projecting mass of masonry or brickwork, to give ad- ditional strength to a wall. CAB 53 CAL c. Cabinet Making- comprises the more delicate kinds of working in wood, applicable to mahogany, rosewood, maple, satinwood, and other choice varieties. Joinery is, in many respects, intermediate be- tween cabinet-making and carpen- try in the materials, the tools, and the processes. A large proportion of modern cabinet-work depends greatly on veneering for its exter- nal beauty. Cable, Chain. Iron now to a great extent supersedes hemp as a material for ships' cables. A chain cable is not simply a chain, for it has a cast-iron strengthening stay- piece across each link, or each alternate link. Nearly the whole mass is made by forging and welding, including the links them- selves, as well as the shackles, swi- vels, and other parts. A chain f cable made of 2j-inch rod iron weighs 272 Ibs. per fathom. The largest ever made (for the Great Eastern) has 2^-inch rod iron. Cable, Hemp. The hempen cables, large and small, are de- scribed under ROPE MANUFAC- TURE. Cable, Telegraphic. (See SUB- MARINE TELEGRAPH.) Cacao. The difference between cacao and cocoa is described under COCOA. Cairng-orm. (See GEMS AND PRECIOUS STONES.) Calabash is the hard shell of the fruit of the calabash tree, growing in the West Indies and Central America. The natives make a suit- able opening in the top, and often decorate the surface with carvings, to convert the calabash into a water- vessel. Calamine. (See ZINC.) Calcine; Calx. When ore is burnt or roasted, the process is sometimes called calcining, and the product calx ; but these names pro- perly belong only to the burning of lime. Calcium. Although calcium is the metallic basis of every Icind of lime, the metal by itself is not used in the arts. We therefore refer to LIME. Calculating' Machine, mecha- nically considered, is an assemblage of wheels, axles, pinions, ratchets, levers, and other small pieces of mechanism, intended to produce movements that shall denote results by means of figures on a cylinder or by hands on a dial. The forms which some of these machines have as- sumed, and the work which they have effected, are truly wonderful. Thomas's Arithmometer, Babbage's Difference Engine, the same remark- able man's Analytical Engine, and Scheutz's Calculating Machine are the principal specimens hitherto produced. Once wind them up like a clock, and these machines would perform the most elaborate calculations, and even print the re- sults upon paper. There is hardly any department of mechanical art more abstruse than the construction of such machines. Calendering- is the imparting of a gloss or glaze to woven goods. It mainly depends on pressure by rollers. The cloth is stretched out smooth by means of wetted rollers ; then stiffened with some kind of paste or size (see DRESSING) ; then stretched out again, either by passing it to and fro on long frames in a warm room, or over steam-heated metal cylinders ; then slightly damped by a fine spray of water; and then it is ready for calendering. The Calendering Machine is a heavy frame containing many rollers, the pressure of which smooths and glazes CAL 54 CAL the cloth ; the surfaces of the rollers are of iron, wood, paper, or calico, according to the kind of gloss which they are required to give. Some of the rollers are indented or embossed, to produce -watered or figured pat- terns at the same time as the press- ing. Some of them are heated from within, some are used cold, accord- ing to the fabric. A more simple and well-known calender is de- scribed under MANGLE. Calibre is the diameter of bore in a gun, cylinder, barrel, or tube, de- noted in inches ; but the term is chiefly applied to guns. It is in- convenient, in matters of ordnance, that while some guns are denoted by the weight of shot thrown (such as "Armstrong 3oo-pounder "), others are denoted by calibre (such as "Rodman 2O-inch gun"). Calico is the cheapest, most use- ful, and most generally-known kind of cotton cloth, probably named from Calicut, in India. Calico Printing-. This beautiful art, comprising mechanical and che- mical processes which require much skill, has been practised in India and China for many nges. In Eng- land it was of much later introduc- tion, principally because cotton came into use among us long after flax, wool, and silk had become well known. In England it is more cus- tomary to speak of printed muslin than of printed calico. The dyes and colours are of two kinds those which penetrate through the whole substance, showing almost as brightly on one surface as on the other ; and tho^e which are intended to be seen only on one side. They comprise nearly the same series of animal, vegetable, and mineral substances as the dyer is in the habit of using ; but there are additional precautions necessary to insure fast colours. Colour Mixing. The colour-house at a print-work is an important place, in which a considerable know- ledge of chemistry must be dis- played. The mills and stones for grinding, the rotating machines for nixing, and the caldrons and Doilers for heating, partake of the usual mechanical character ; but there is much else to attend to in relation to the qualities of the various dyes and colours. Some must be thickened with starch, or flour, or gum, to make them act more like a paint than a dye ; some have the mordant combined with the colours, instead of being used sepa- rately ; some require a liquid vehicle that would be inappropriate for others ; some require steam to act upon them after they have been applied to the cloth. Block Print- ing. In the early days of cotton- printing, the pattern or device was engraved on the surface of a large square block of sycamore, holly, or pear wood ; and this plan is still adopted for choice patterns of which only a small supply is likely to be needed. The pattern may be engraved on any kind of smooth wood, or may be built up in relief with narrow slips of cop- per, or may be reproduced by elec- trotype. The colour is spread out on a cushion or pad ; the block, held by a handle at the back, takes up a thin layer of it ; this layer is applied to the cloth, smoothly spread out on a table, and so on. If the pattern comprises many co- lours, there is one block to each ; and the blocks are used in regular succession, each filling up its proper place in the design. The cloth is shifted on as fast as it is printed, and a new portion brought forward at each shifting. Perrotine Print- ing. A machine for block-printing, called the Perrotine, is used in France and Belgium. Three long wooden blocks, engraved with the pattern, are made to fit upon three sides of a square prism of iron. The prism rotates upon a horizontal axis ; the calico or muslin passes between the prism and the bed ; CAL 55 CAM and the action is such that the calico receives a long stripe of coloured pattern every time it touches one of the blocks. Cylinder Printing. This is the kind by which the great bulk of printed goods is produced. The pattern is engraved on a roller or cylinder, instead of on a flat block. The roller is of copper or brass; a coating of varnish is given to it '; the pattern is etched on the varnish with a diamond point, and then eaten in or engraved by the action of dilute nitric acid. Sometimes the engrav- ing is impressed by Perkins's rolling machine, now so much used in other kinds of engraving; sometimes, again, the engraving is done by an engine like that employed in engine- turning; and occasionally the rollers are of wood, with a pattern made by inserted slips of copper. The rollers are from 30 to 40 inches long, by 4 to 12 in diameter. There are as many rollers as there are colours one to each ; there are also as many distinct troughs or cells of dye-stuff or pigment as there are colours ; and the cylinder machine is a skilfully- planned apparatus, by which all these rollers and troughs can be brought into action, each one just at its pro- per time and in its proper place. Some elaborate patterns have as many as twenty different colours and shades of colour, and then the ar- rangements are very complicated ; but from one tofouris the most usual number. So perfect are the adjust- ments that one mile of calico can be printed with four colours in one hour. Accessory Machines. The machines and processes accessory to the actual printing are numerous. The printed cloth is dried by a gas- heated drying machine ; and then transferred to the ageing-room, where the action of the air, aided sometimes by a little steam, causes the colours to adhere more firmly to the fibres. The clearing-beck is a vessel in which the printed cloth (if some particular kinds of colour are used) is scoured with soap and water ; and there are washing ma- chines also with clear water only. The Madder style is the name given to a particular series of pro- cesses where the printing is with a machine chiefly used when madder is the principal dye. The Indigo style denotes another series of pro- cesses, where the printing is with a resist paste, which prevents the dye from attacking those particular spots. The Padding style is a third series, mostly suited for mineral co- lours, and requiring some of the colours to be in a thickened state. The Discharge style is a fourth (al- ready noticed under BANDANA). The Steam Colour style, largely em- ployed for furniture chintzes, requires the action of steam to fix the colours upon the cloth. Mr. Cola gives an estimate for an establishment which comprises four cylinder machines (of one, three, four, and six co- lours respectively), and a propor- tionate supply of washing, drying, roller-engraving, roller-ruling, co- lour-grin'ding, starching, mangling, and steam-drying machines, with the si earn engines, boilers, and mill gearing for working them ^"8,000 ; 2X25O for bleaching machinery (as further bleaching is sometimes ne- cessary at the print-work itself) ; and ^650 for a mechanics'-shop ma- chinery, to keep all the engines and machines in repair. Calimanco is a checked woollen stuff, so woven that the check is visible on one side only. Caloric Engine. ( See HOT-AIR ENGINE.) Cambric is the finest and thin- nest kind of linen or flax fabric ; but the name is sometimes erroneously given to fine cotton goods which are properly muslins. Cameo. A cameo, mechanically considered, is a gem or hard stone with a device in relief upon it. Usually some stratified stone, such as onyx, is selected, which will give CAM CAN slightly different tints to the raised part and to the background^ Very beautiful cameos are now cut in shells specially chosen for their varied tints. Camera Lucida, invented by Dr. Wollaston, is an apparatus containing a glass prism with angles of definite measurement. When the light from any object falls on one side of the prism, it is reflected down upon a piece of paper, and an eye, placed near one angle, sees the image and the paper at the same instant. The instrument assists in drawing or delineating, but is now nearly superseded by photography. Camera Obscura, as a scientific instrument, has not much connection with the manufacturing arts ; but in photography it is almost indispen- sable. It is a box with an opening at one end to receive a lens ; and there is a kind of telescopic action which allows this lens to be brought into various positions for adjust- ment of focus. At the other end of the box is a screen of ground glass, so placed as to receive the image of any object focalised by the lens. For a common camera there | is an intermediate reflector at an angle of 45, which throws the image on a horizontal ground glass, where it appears as a small picture. For a magic lantern painted slides are used. For photography, the image is received on a sensitive sur- face of paper or glass, contained in a camera slide. Camlet is one of the numerous varietiesof woollen, or rather worsted goods ; it was made originally of goat's hair, but is now of sheep's wool, wool and cotton, or wool and flax. Campeachy Wood. (See LOG- WOOD.) Camphine is one of the many liquids which have lessened the use of whale oil for lamps within the last few years. It is really a spirit of turpentine, obtained from the sap of the pine-tree in America. It has lately been rather superseded in favour by some of the rock-oil and coal-tar liquids. (See ROCK OIL ; COAL TAR.) Camphor, a whije solid obtained from many essential oils, and from the camphor tree in particular, how- ever useful in medicine, has not yet been made available in any great degree in the manufacturing arts. Canada Balsam, a turpentine obtained from a species of fir, is use- fully employed as an optical cement and as a varnish. Candle Manufacture. A candle, when once lighted and set steadily burning, is really a beautiful exem- plification of chemical philosophy ; but as an article of manufacture it is rather mechanical than chemical. Dip Tallow Candles. The com- mon dip or store candles are made of the coarsest kinds of tallow. The tallow is melted in an open copper ; the membranous portion, separated from the fat, forms greaves or crack- lings, and is used as dog food. The fat, deprived of the membrane, is strained and further cleansed, and laid aside for use. The wicks are | made of cotton rovings or soft i threads, combined in various ways, and cut off to the proper length, slightly coated with tallow to stiffen them. The wicks are hung side by side on a stick called a broach. The tallow being melted, the wicks, hanging from the broach, are dipped many times in succession, being allowed to solidify after each dipping. Many broaches are sus- pended from one balanced beam, so as to dip a considerable number of wicks at once. Some of these beams are large machines, having a thou- sand or more wicks suspended from them, which are dipped into the melted tallow in groups or clusters. Mould Tallow Candles. Mould candles, smoother and better made than dip, have a proportion of mutton suet mixed with the beef CAN 57 CAN Callow. Each candle is made in a pewter or glass mould, down the middle of which the wick is ad- justed ; and there is a conical cap at one end, through a hole in which the wick protrudes. Many such moulds are placed, cone downwards, in a frame ; melted tallow poured upon the frame fills all the moulds thereby making an equal number ol candles. The machine comprises a number of very ingenious adjust- ments for threading the moulds with wicks, keeping them stretched straight, cutting them off to the proper length, and removing the candles from the moulds when made. Wax Candles and Tapers. Wax does not suit well for making mould candles. They are therefore produced by pouring melted wax out of $ ladle upon a series of pre pared wicks suspended from a ring over the vessel, the wicks being kept twisting meanwhile. When the candles are thick enough, they are rolled hot with a smooth flat piece of boxwood on a wetted table of smooth walnut wood. The large wax candles for altar lights are made by placing the wick on a slab of wax, and rolling the latter around it. Wax tapers are made something in the same manner as wire is drawn : a long wick, drawn off from a reel or drum, is passed through a vessel of melted wax, and dragged through a hole, which gives an equable thickness to the long pipe or taper thus produced. Miscella- neous Kinds. If we take the five modes of making dip, -mould, wax, altar, and taper candles, we pretty nearly exhaust the mechanical means employed in this manufacture. Most of the other varieties depend on the kind of tallow or fat, and on the kind of wick. Rushlights are made of rushes coated with any kind of tallow or solid fat by the dip method. Stearine candles are made of a purified material, tallow being deprived of its oleine, or oily con- stituents, and only the stearine, or solid white constituents, being used. Palm candles are made of palm oil, which, though liquid as obtained in Africa, is a solid in temperate climates. All candles of the stearine and palm class are made in moulds. At Price's celebrated candle-works at Vauxhall, the machines would contain wick enough at one time for 500 miles of palm candles. Night lights are tiny candles made for a special purpose: a cheap mode of obtaining a small light for a certain length of time. The Albert lights are short, thick mould candles with a hole down the axis, in which the wick is afterwards placed by hand . Child's night lights have a waxed wick on a tin support, held upright in a small paper box filled with tallow; the box, when used, rests in a little water in u saucer for coolness and security. Price's night lights are somewhat similar in construction, but cheaper. Most of the best candles now made require no snuffing. By com- bining two or more wicks together, previously giving a peculiar twist to each, and sometimes coiling a thin wire around them, the entire wick unwinds as it burns ; and the ends, emerging at the edge of the flame (where they come in contact with the air), they burn away, and thus leave nothing for the snuffers to deal with. 5,000,000 Ibs. of English-made candles were exported in 1867, after supplying home wants. Canes. (See BAMBOO ; RAT- TANS.) Cannel Coal. (See COAL.) Cannon Pounding-. Brass or Dronze guns are cast in loam moulds. A centre is formed of a wooden bar, with rope coiled round it, and then clay to a certain thickness. This gives hape to a mould or shell of loam, and then the centre is removed. The nterior of the loam mould will give brm to the exterior of the gun. To Dioduce any ornaments and inscrip- CAN CAR tions, small devices are modelled in wax, and fixed on the clay centre before the loam is applied ; being melted out aftenvards, their places form cavities on the inner surface of the mould, which will produce relievo ornaments on the exterior of the gun. When the moulds are ready, they are placed upright in a casting pit, and the molten brass passed into each by proper apertures. Some cannon are, however, cast solid. Iron cannon are cast nearly in the same way as above described, with somewhat more powerful ap- paratus on account of their usually large size. The names given to the different kinds of cannon are in- definite and confusing. Before the recent improvements made by Arm- strong, Whitworth, Palliser, Fraser, and others, iron shell guns were of 8, IO, and 12 inches bore ; iron mortars of 8, 10, and 13 inches bore; iron howitzers of 8 and IO inches bore ; brass -mortars of 4 and 5 inches bore; long iron guns, 9, 1 2, 1 8, 24, and 3 2 -pounders ; long brass guns, J > 3> 6, 9, and 12-pounders; short iron guns, or carronades, 12, 1 8, 24, 32, -42, and 68-pounders ; brass howitzers, 12, 24, and 32-pounders. Some of the designations are now falling into disuse, and new forms of cannon are quickly appearing. Whether a cannon be cast in a mould, or made by coiling strips of wrought-iron or steel round a mandril, the interior requires to be made very smooth and regular ; this is done by boring, sharp-cutting tools being used, and either the tools or the cannon being made to revolve far more elaborate work- ing being needed when the bore is rifled. (See RIFLE.) The grandest gun in the world, for size, weight, cost, and beauty of workmanship, is that which Krupp, of Essen, in Prussia, made for the Paris Exhi- bition of 1867 cast steel, 50 tons weight ; 1 7^ feet long, 1 4-inch bore, i,2OO-pounder ; took sixteen months to manufacture, and cost ^16,000. The same Exhibition contained a Woolwich muzzle-loader, 23 tons, 12-inch-bore, 6oo-pounder; a Whit- worth 25O-pounder ; and a Palliser 9-inch, 25O-pounder. Canoe is, properly speaking, simply a hollowed trunk of a tree used as a boat; but such canoes as Mr. Macgregor's celebrated Rttb Roy, with which he has made so many long voyages, is a boat of very careful construction. Canvas is a general name for coarse textile fabrics, such as sailcloth generally, though not necessarily, made of hemp. Caoutchouc is the native Indian name for what is better known to us as india-rubber. Cap, Percussion. (See PER- CUSSION CAP.) Capstan is a powerful machine for moving heavy weights. In general construction, it has a vertical barrel around which a chain or rope winds ; a pivot and spindle on which the barrel rotates ; a series of lateral holes in which lever-bars may temporarily be inserted ; and other appendages. Men, working with the lever-bars inserted in the holes, cause the barrel to rotate, and thereby wind up the rope or chain, to the other end of which the weight is attached. Many improved forms of capstan are in use ; some designed for ship use, some for land. Caramel, made of burnt sugar, is used to darken the colour of wines, spirits, and vinegar. Carat is a peculiar weight em- ployed by jewellers. For gold and silver it is not, however, an actual weight, but a proportion, to denote how much pure metal there is in an alloy, ff is fine gold, is " 18 carats fine," - is " 12 carats fine," and so on. (See further under COINS; STANDARD; STERLING.) For diamonds the carat is an actuai weight 3^ troy grains. Carbine is a kind of short cavalry CAR 59 CAR rifle, with a barrel 22 to 26 inches long, light in weight, and handier for many kinds of service than the infantry rifle, which is much longer. The connection between the carbine and various other kinds of weapon is noticed under SMALL ARMS. Carbon, when absolutely pure, and in the crystalline form, is known to us as diamond. When nearly pure, but non-crystalline, it forms charcoal, which may be obtained by a careful mode of burning certain animal and vegetable substances. Substances consisting of very little else than carbon are anthracite, plumbago (or so-called black-lead}, and coke, all of which are described under their /proper headings. Car- bon combines with other sub- stances in numerous forms. With oxygen it constitutes carbonic acid purposely made in preparing aerated bread, soda water, &c. This carbonic acid, combined with metals, earths, and alkalies, pro- duces the substances known as carbonates, so invaluable in the arts. W T hen carbon combines, not with oxygen, but with other simple substances, it produces carburets instead of carbonates : these, in the solid form, are not to any large ex- tent useful ; but the gaseous com- pound of carbon and hydrogen, forming carburetted hydrogen, may be taken as the type of all our most important materials for artificial heating and illumination. Carbuncle. (See GEMS AND PRECIOUS STONES.) Carburetted Hydrogen. (See GAS LIGHTING.) Carcass is an iron shell fired from a mortar during sieges, to set fire to buildings in the besieged town. It is hollow, 4 to 13 inches in diameter, and is crammed with an infernal mixture of gunpowder, saltpetre, sulphur, pitch, resin, tur- pentine, and tallow. Cardboard is, in principle, no- thing but thick paper ; its greater substance, however, necessitates ad- ditional manufacturing processes, seeing that it is really two or more sheets of paper cemented together. Cardboard, for playing and address cards, consists of cartridge paper with finer paper on the two- surfaces. Bristol board consists of fine paper throughout its whole substance. Millboard is made of coarser and heavier paper, but is rendered smooth and glossy by heavy rolling. Pasting, pressing, drying, and roll- ing are the chief processes in the manufacture of all the varieties. Some cardboard is enamelled by means of a very fine preparation of white-lead, rubbed on, and brushed in a peculiar way. Cards; Card Setting-. Under COTTON, FLAX, HEMP, JUTE, WOOL, WORSTED, &c., are noticed the cards, or assemblages of wire teeth, with which the fibres are combed out before spinning ; and also the carding engines which ena- ble steam power to be applied to the working of these cards. There is a very beautiful engine, Crabtree's Wire Card-setting Machine, which inserts all the wires in the curds by self-acting movements. Wire is fed into the machine, and also the fillets which are to form the cards. The wire is cut into short pieces ; each piece is held firmly, and the two ends bent to form a staple ; a pricker makes holes in the fillet ; the pieces of wire are inserted in the holes ; while supplementary parts give force and finish to the teeth thus made. The fillet travels on just as fast as these operations are completed. Cards, Playing-. A specially- prepared kind of cardboard, with a semi-enamelled surface, is required for these. The coloured devices on the two surfaces are done partly by stencilling, and partly by block colour-printing. In most cases the colour is mixed up with water and size, but some cards are printed ia oil colours. CAR Careening- is a dangerous ma- noeuvre, not often adopted now, of tilting a ship on one side in order to expose the other side for bream- ing. It was over-careening that caused the upsetting and loss of the Royal George in Portsmouth har- bour in 1782. Large vessels are now more frequently lifted fairly out of the water by some kind of floating pontoon, caisson, or gridiron. Carmine is the substance that gives the beautiful colour to the cochineal insect. The insects are boiled in alkaline salts, an extract is obtained, and carmine results as the reward for a series of carefully-con- ducted processes. It is the most intense and beautiful of all red colours. Miniature and water-colour painters are the chief users of it, owing to the high price ; but it is sometimes used in dyeing silks and artificial flowers. Colour-makers adopt various modes of imitating real carmine by means of Brazil wood, sandal wood, and other substances. Carnelian. (See GEMS AND PRE- CIOUS STONES.) Carpentry, as distinguished from joinery, is the timber- work of build- ing and engineering, in which no decorative features are looked for; whereas the joiner works with smaller pieces, to which he gives a higher finish. Names of Timber Pieces. In some arrangements of wood-work the timbers tend to bend, in others to compress, in others to stretch. If the duty of a particular piece is to take longi- tudinal compression, it acts as a strut ; if to take longitudinal ex- tension, or stretching, as a tie ; if a single timber is strengthened by subordinate pieces, it is a truss ; a joint for lengthening a timber, by adding pieces at the ends, is a scarf ; a joint for connecting timbers to form a truss, roof, cen- tering, &c., is usually a tenon and mortise ; joints for connecting tim- bers in braces, ties, &c., are dove- 60 CAR tails, crampings, notchings, lap- pings, &c. Wall-plates distribute the pressure of the roof on the walls of a building ; principal rafters are timbers to support the framework of the roof; tie-beams and collar- beams are timbers to connect these rafters ; purlines are horizontal pieces which connect the principal with the common rafters ; pole-plates connect the common rafters with the tie-beams ; king-posts are up- right pieces from the tie-beam to the principal rafters ; queen-posts are similar in character, but different in position ; struts and braces are dia- gonal strengthening pieces ; pun- cheons, or studs, are short pieces placed between two others to sup- port them equally ; straining-beams are placed between the queen-posts ; straining-sills are placed upon the tie-beam at the bottom of the queen- posts ; camber-beams are horizontal on the lower surface, but obtusely angular on the upper. The modes of fastening the various pieces to- gether give rise to the processes of scarfing, plain jointing, notched jointing, dovetailing, mortising, re- bating, &c., which, in fact, consti- tute the chief features in practical carpentry. Carpenters* Tools. Of the carpenter's tools the saw, axe, adze, plane, screw-driver, pincers, hammer, gimlet, bradawl, chisel, goitge, centrebit, rimer, square, level, plumb-line, &c. such as need any description are noticed under their proper headings. The applica- tion of steam power to the working of machine tools for this purpose is treated under WOOD-WORKING MA- CHINERY. Carpet Manufacture. The naming of carpets after the places where they were first made is no longer locally correct; but as the custom continues, it may be con- venient to follow it here. Turkey carpets are made on a vertical loom ; the warp threads (linen) being unwound fiom an upper CAR 61 CAR beam, and wound round a lower beam as the weaving goes on. The weaver throws in the weft threads with a shuttle; but he introduces, with his fingers little bits of coloured wool, which are twisted round the warp, and jammed up closely by the weft. Each little tuft or bunch is chosen of the proper colour, ac- cording to the pattern ; and there- fore the selection and tying on of these bits form the generic pecu- liarity of the Turkey carpet. The surface is afterwards sheared, to bring the tufts t> a level. Axmin- ster carpets are virtually imitations of the Turkey ; they are not now much made. .Brussels carpets have a linen web or foundation, with wor- sted yarns raised into loops to form a pattern. These loops are formed by means of wires, temporarily laid across the warp, the yarns being placed over the wires, and then the loops left when the wires are re- moved. The coloured threads to form the yarn are wound upon bob- bins fixed in frames at the back of the loom. A complicated mecha- nism of weights, bench-wires, rails, cords, and pulleys is necessary to connect the several bobbins with the working part of the loom ; and then the incorporation of linen warp, linen weft, and worsted yarns, so as to form at once a strong fabric and a coloured pattern, is effected by a very intricate succession of movements. The wires are drawn out at the selvage edges of the carpet, and the loops which they leave form the visible surface. Wilton carpets differ from Brus- sels chiefly in this that each wire has a groove along its upper surface, which guides a knife employed to sever all the loops, and thus disen- gage the wire. The surface of the carpet is thus a pile of cut ends, and this pile is afterwards sheared to make it a level smooth nap. Kidderminster carpets have a peculiar double structure, being, in fact, two separate carpets linked together. The two are woven simultaneously, and at the same time are linked together. The warp is worsted, and the weft woollen. The visible pattern is mostly formed by the weft, the warp being more buried within the substance of the fabric. The weft of the lower web is at periodi- cal intervals brought up to the sur- face, and does its part towards forming the pattern. A Kidder- minster carpet, from the mode of its construction, presents the same pattern on both surfaces, only with the colours reversed. Scotch carpets are very similar in general character to Kidderminster, but many of them have three thicknesses instead of two ; they consist of three webs, curiously interlacing, and called three-ply. Venetian carpets are so woven that the warp gives the pat- tern, the weft being wholly con- cealed. This is the cause of the stripes which these carpets usually exhibit. By a suitable selection of weft colours the stripes may be converted into checks, tartan, and twilled patterns. Dutch and British Venetian somewhat resemble Vene- tian. Tapestry carpets are made of yarns printed before being used, in such a way that each yarn shll present different colours in different parts of its length. A pattern is thus produced with less complexity of apparatus than for the Brussels or Wilton carpet. /^//carpets are, in fact, nothing more than printed pieces of felt used as cheap sub- stitutes for real carpets. Our exports of carpeting in 1867 amounted to 6,700,000 yards, after supplying home demand. Carriage. (See COACH MAK- ING.) Carronade. (See CANNON FOUNDING.) Carton-Pierre. (See PAPIER- MACHE.) Cartridge is a tube or case to CAR 62 CAS contain ammunition, to be shot from some kind of fire-arm. The primary use of it is to save time in loading. Cartridges for cannon are bags of gunpowder, and some- times bullets, fastened up in a con- venient way. Cartridges for fowl- ing-pieces, muskets, carbines, &c., are tubes of paper, pasteboard, or brass, each containing a definite quantity of powder, if for a blank cartridge ; if for service, the tube also contains a bullet or else shot. The making of cartridges for the Snider- Enfield rifles is now carried on in a very complete way at Woolwich. Carvel-built, in boat-building. (See CLINCHER-BUILT.) Carving 1 . From the softest pith and cork to the hardest ivory and ! bone the carver has his range ; and his chisels and gouges follow the lines which have been marked out by the design. Machine Carving. Carving by machinery is a very dif- ferent affair. Art and taste produce the design, but iron fingers do the work. Mr. Jordan, about 1846, in- vented a clever series of machines for carving in wood; others had been before invented, but had failed through various causes. There is a model or pattern laid down upon a bed-plate ; there is a blunt tool or tracer to follow all the sinuosities of the pattern ; and there are rapidly- revolving cutting-tools to make cuts or incisions in a piece of wood in accordance with these markings. The piece of wood moves about in all directions horizontally by the movement of the table on which it is fixed; while the tools rise up and down, and rotate rapidly, according to the depth of the work. Such are the main features ; and Jordan's ma- chinery gives practicability to them by a multitude of ingenious contriv- ances. The tracer dips down upon all the inequalities of the pattern ; the cutter dips down to exactly the same depth upon the wood. The tracer goes over every part of the pattern in turn, and the cutter does the same all over the wood. Steam power supplies the actual revolution of the cutters, but the workman sees that this power is properly applied. Small wheels and tramways assist in this adjustment. Most of the carv- ing at the Houses of Parliament was executed by machines. A some- what coarse variety of carving is done by the apparatus described un- der WOOD-WORKING MACHINERY. Case-hardening- is a mode of giving a steely appearance to a sub- stratum of iron, very important for many manufacturing purposes. Car- bon is added to the iron, as in the making of steel (see STEEL MANU- FACTURE), but not in the form of charcoal : various substances con- taining carbon, such as hoof, horn, and bone, charred and pounded, are used for this purpose. The articles to be case-hardened are boiled in such kinds of powder in a proper receptacle, and kept at a red-heat for half an hour or so ; this impreg- nates the surface of the iron with a little carbon, and converts it into steel seldom more than -j^-th inch thick. There is a mode of using prussiate of potash as the envelop- ing material, which greatly shortens the process. Case Shot, or Canister Shot. These names are given by artil- lerists to cylindrical canisters fired from cannon. Each canister con- tains many bullets, which scatter around destructively when the ca- nister itself bursts. Cashmere Shawls. A Cash- mere shawl of the choicest kind, weighing 7 Ibs., has been sold in India for the enormous sum of ^300 more than half its own weight of pure gold. The real substance itself, the shawl-wool or pushun, is a fine, delicate, downy fleece, which grows between the skin and the thick hair of the Cashmere or Tibet goat ; it is worth "js. per Ib. even in Cashmere. But there are CAS CEM various kinds of cloth made in that part of India from Cashmere wool, and used for robes, caps, tur- bans, girdles, canopies, curtains, saddle-cloths, trousers, stockings, leggings, &c. ; and there are almost as many varieties of wool employed in that manufacture as in England. In the shawl manufacture, the most scrupulous care is taken in the pro- cesses of scouring, bleaching, dye- ing, spinning, ami weaving ; while the patterns are designed by draughtsmen whose taste is espe- cially cultivated to this end. English and French Cashmere shawls are sometimes made wholly of Cash- mere or Tibet wool, and sometimes of a mixture of that with sheep's wool, but are often mere imitations, wholly of sheep's wool. There is also Cashmere cloth for ladies' man- tles, &c., of which the Tibet goat is in all probability quite innocent. Cask Making. (See COOPER- AGE.) Castile Soap. (See SOAP.) Casting- and Founding 1 . There is no real difference in the meaning of these two terms, except that cast- ing sometimes means pouring a cold liquid (such as liquid plaster of Paris) into a mould, whereas found- ing always implies the use of a molten metal. The mould for large metal castings is mostly formed in some kind of sand or loam, but occa- sionally in iron. For some articles, such as plates and slabs, molten metal is poured out upon a smooth horizontal bed of sand ; for others, into an upright moulded cavity open at the top ; for others, again, into a mould enclosed on all sides except an aperture or two to receive the flow. Very often a sand mould is made by pressing a wooden pattern upon or into the sand, thereby pro ducing cavities which are afterwards to receive the molten metal. Some moulds contained in iron boxes are hinged together in two parts, to facilitate opening and closing. For casting small articles in brass, iron casting-boxes, called flasks, are em- ployed; the sand contained in these receives its mould form from a pattern ; and the same flask will then serve for an indefinite num- ber of different patterns in brass. In large iron castings (of which examples are given under CANNON FOUNDING; CYLINDER CASTING), the metal is melted in a furnace con- structed for this particular kind of work. (See CUPOLA FURNACE.) When the metal is melted, it flows out of the opened tapping-hole either into channels in the casting-floor, or into ladles, which are of such varied sizes as to contain from 50 Ibs. to 6 tons each the latter, of course, worked by powerful machine cranes. From the ladles the metal is poured into moulds. Most articles are cast horizontally that is, with the length and breadth horizontal ; but such articles as cylinders, cannon, pipes,- shafts, &c., are cast vertically, and mostly in pits. Most castings, when removed from the moulds and cleansed from the adhering sand, &c., require the seams and rough edges to be smoothed down by chisels and files. Catechu, Cutch, or Terra Japonica, is an extract from the wood of a particular tree growing in the East Indies, solidified into cakes or balls. It is a very useful substance in dyeing for giving brown, drab, and fawn colours. Catg-ut is a misnomer. It is usually the intestine of the sheep, cleansed, steeped, scraped, treated with alkaline solution, and otherwise prepared. The substance is then used for violin and harp strings, clockmakers' cord, whipcord, bow- strings, &c. The intestine of the horse, ass, or mule is sometimes used instead of that of the sheep. Caulking-. (See SHIPBUILDING.) Cedar. (See BLACK-LEAD PEN- CILS; TIMBER.) Cement, as an adhesive bond to CEM connect two substances together, is very varied in character. Several kinds are noticed under CON- CRETE, GLUE, GYPSUM CEMENT, HYDRAULIC CEMENT, MARINE GLUE, MORTAR, ROMAN CEMENT, SOLDER, &c. Plaster of Paris and thin glue ; plaster of Paris, paper pulp, and size; red-lead, white-lead, and boiled linseed oil ; quicklime and ox-blood; iron borings or turnings, sal ammoniac, and flowers of sulphur; iron borings, pipe-clay, powdered earthenware, salt, and water; litharge, fine sand, quicklime, and boiled oil ; chalk, lime, salt, sand, clay, and iron filings ; resin, bees'-wax, red ochre, and plaster of Paris ; shellac and india-rubber; quicklime, cam- phor, and curdled milk ; gum mastic, spirit of wine, isinglass, brandy, and gum ammoniacum ; quicklime and white of egg ; resin, brickdust, and bees'-wax ; all are mixtures which constitute cements useful in some or other of the arts. Isinglass, Canada balsam, copal varnish, mastic varnish, may all be used singly as cements. Cementing: Furnace. This fur- nace, employed in converting iron into steel, somewhat resembles a glass furnace in external appearance. It consists of a brick cone or hood 30 to 40 feet high, within which are two horizontal troughs of fire-stone or fire-brick. A grate extends the whole way between and beneath the troughs, open at both ends, and pro- vided with a number of flues and air-holes. The cementing furnace is also called a converting furnace. For the mode of using, see STEEL MANUFACTURE. Centering 1 , in carpentry, is a kind of scaffolding or framework on which arches are built. The upper surface gives form to the arch. The bit of board, with a curve at one end, with which the bricklayer guides himself in forming the arched heads of windows and doors, is a centering; the magnificent scaffold- 64 CHA ing employed in building the roof of the Midland Railway .Station at St. Pancras was a centering ; and the carpenter's art exhibits every grada- tion between these two extremes. Sometimes the timber framework for centering is strengthened with a good deal of iron. In building the arches of our more celebrated bridges, such as London, the mo- dern Westminster, and Blackfriars bridges, the centering is constructed with great skill, to enable the tim- bers to bear the enormous weight which presses on them, and to faci- litate the removal when the arch is finished. Ceramic Manufactures. This is simply a kind of fine-art designa- tion for the work of the potter, whether in porcelain, common pot- tery, or decorative terra-cotta. Chain Cables. (See CABLE, CHAIN.) Chain Shot consist of two cannon balls linked together by a chain. When fired from a gun, the chain enables the balls to work greater destruction than if they were separated. Chain Work. (See HOSIERY MANUFACTURE.) Chalcedony. (See GEMS AND PRECIOUS STONES.) Chalk is chiefly used in the arts to burn into quicklime, and as a manure. It is a soft variety of lime- stone, or carbonate of lime, slightly impregnated with other substances. Crayons, Vienna -white, and pastel colcnws are prepared from it. Challis is a kind of thin soft Norwich crape, made of silk and worsted; it takes beautiful, patterns either by weaving or by printing. Chameleon Mineral is a com- pound of manganese and potash, and is used in bleaching tallow, palm oil, c. Chamois Leather was the original and proper name for what is now more often called Shamoy Leather,. CHA e Charcoal Burning. The most use- ful form of carbon is prepared by burn- ing wood in such a way as to drive off most of the hydrogen, leaving a sub- stance which will give out much heat without flame. This process is car- i icd on more extensively on the Con- tinent, where wood is plentiful and coal scarce, thari^in England. Char- coal-burning is done in four ways : (i.) Logs of wood are piled up, some horizontally, but mostly verti- cally, and packed together as closely as possible, until they form a kind of hemisphere or low beehive, varying from I o to 60 feet in diameter. The mound is covered with layers of turf. Fire is kindled near the centre by a hole left for the purpose. The wood sweats that is, gives off its mois- ture ; then begins the charring. This charring continues many days, or even weeks, with small inlets for air, and small outlets for steam or mois- ture. When the charring is done, by the conversion of the wood into char- coal, the mound is cautiously pulled down, and the pieces removed. (2.) The logs are ranged into a sort of wedge form, 30 feet long, and varying from 2 to 9 feet in height. They are arranged in this way to facilitate their charring, and are roofed in with twigs and charcoal powder. The pile is kindled by red- hot coals. (3.) A pit is dug on the side of a hill, and covered with earth. An opening is left, leading to a vessel where tar is collected as one of the products; for, when well conducted, the process is a kind of distillation, with charcoal as one product and tar as another. (4.) A furnace is regularly built up, with a domed top ; and the charring is so conducted as to save all the tar and pyroligneous acid, which have a marketable value. Any kind of wood may be em- ployed to make charcoal ; and the different sorts thus produced are applicable to different purposes. Charcoal is not fusible even at the ; CHE highest heat. It is employed as fuel in many branches of manufacture, owing to its greater purity than coal. It has a remarkable power in removing colour, taste, and odour from various substances. In powder it forms a very serviceable polish- ing and cleansing material. Bone- black and ivory-black are examples of animal charcoal. Charqui, or jerked beef, is a food largely prepared and consumed in South America. The lean flesh of cattle is cut into steaks about an inch thick, dried in the sun, and packed for sale ; it remains untainted for a very long time. Some of it is salted before drying. (See further under FOOD, PRESERVED.) Chasing, in metal manufactures, is a mode of ornamenting the surface of gold, silver, bronze, or other choice metal. It is a sort of medium between engraving and carving not so fine as the first, finer than the second. Cheese Making. Cheese bears some such relation to milk that but- ter does to cream. Curdling. Milk, coloured to the required tint by ar- natto, has a little rennet added to it. This rennet, an acid liquor prepared from the stomach of a sucking calf, has the property of curdling the caseous portion of the milk, and separating it thereby from the whey, or watery portion. This curd, which is in great lumps or masses, requires to be broken up smaller by the hands of the dairymaid, or by the aid of a curd-cutter, imde of copper. The broken curd sinks to the bot- tom; the whey is laded from the top, either to be made into whey butter, or to serve as pig-drink. Moulding. Then ensues the moulding of the curd into the form of a cheese. The curd, cut into pieces with a knife, is thrown into the mould or -vat, an elm vessel with holes in the bottom ; the vat is not only filled to the top, but is heaped up, in order to allow for compres- CHE 66 CHL sion. Pressing. The cheese-press is formed in various ways. The best consists of an iron frame, plunger, pinion, ratchet wheel, and lever, capable of exerting a graduated or regulated pressure. Whatever form of press is used, the cheese remains under pressure for some time, with precautions for removing occasion- ally all the whey that may be squeezed out. The cheese is wrapped in linen cloth in the vat ; and this cloth is frequently renewed, to insure cleanliness and dryness. Salting. The pressure being com- pleted, the cheese is removed to the salting-tub, and covered with brine, to which it is exposed for several days. This is followed by rubbing with dry salt on both surfaces, many times repeated. After this come dry- ing, wiping, and ventilating. In some kinds of cheese the salt is mixed with the whey in the first instance. Cheshire cheese is the best known and most important in England ; it is made from the whole milk. Stil- ton, rich in quality, is made of the cream of evening milk mixed with the next morning's milk ; it is not ripe for use until two years after being made. Double Gloucester is made from the milk and cream mixed ; Single Gloucester from half new and half skimmed milk. Many other districts in England are asso- ciated with the making of cheese of excellent quality. Dutch cheeses, nearly as round as a ball, are sound and substantial in quality. Parme- san cheese, though of skimmed milk, has a peculiarly delicate flavour. Gruylre cheese, made in Switzer- land, is flavoured with herbs. American cheese, somewhat strong in flavour, is rather largely in use on account of its comparative cheap- ness. Cream cheese is made from cream curd without pressure. Our make of cheese is far below the home demand ; the imports in 1867 were 900,000 c*vt., whereas the ex- ports were only 30,000 cwt. Chert, a kind of flinty mineral, is used in pottery manufactures. Chestnut. (See TIMBER.) The young trees are used for hop and espalier poles, and the bark for tanning. Chicory, largely used as a sub- stitute for, or an addition to, coffee, is obtained from the roots of the chicory- plant, which grows in most parts of Europe. The roots, when pulled up, are washed, cut up, dried, roasted in revolving ovens, and moistened with a little butter; the brown mass is then ground up like coffee. The cheap chicory in the shops is largely adulterated with various substances. Chimney. As a useful rather than an ornamental part of a build- ing, a chimney should (but too often does not) bear close relation to the due prevention or consumption of smoke. This might be done to a much greater extent than it is. (See SMOKE CONSUMPTION.) In large chemical works, chimneys are made of immense height, to carry off all deleterious fumes as high as possible into the air : some of them have exceeded 400 feet in height. China Clay, or Kaolin, is one of the most important ingredients used in the porcelain manufacture. China Grass, the fibre of a plant growing in the country which has given it its name, is woven into a textile material known as grass- cloth ; the cloth is fine in texture and glossy in appearance, and is used for handkerchiefs. China Ware is the popular name for what is described in this volume under PORCELAIN. Chintz is a kind of thick printed calico, usually glazed after printing. Chlorine, a gas, and one of the simple substances, is of vast import- ance in its combinations. The in- exhaustible source whence it can be obtained is salt, whether rock salt, brine, or sea water, salt being a chloride of sodium. Combined with lime, chlorine forms the invaluable CHL I chloride of lime. (See BLEACHING POWDER.) With metals it forms the chlorides, many of which are used in the arts. Chlorate of potash, of which it is a constituent, plays an active part m "many detonating and igniting substances, such as that which tips lucifer matches. Many compounds of chlorine are powerful disinfectants. Chloroform is at present used chiefly in medicine to lull pain ; but there are many uses in the mecha- nical arts which it is likely to sub- serve. It is a volatile, limpid, co- lourless liquid, composed of chlorine, carbon, and hydrogen, and is ob- tained by distillation from wood- naphtha. Chocolate. The relation between Chocolate and COCOA is explained under the last named-heading. ChokeDamp. (SeeFiRE DAMP.) Chrome Yellow, or chromate of lead, is made by mixing chromate of potash with nitrate of lead ; a brilliant yellow precipitate falls, which constitutes chrome yellow, a valuable pigment for the painter. On boiling this substance with lime water, it becomes changed to a sub- chromate of an orange-red colour. Another mode of preparing this subchromate gives it a beauty of tint almost equal to vermilion. One variety, the dichromate, is a scarlet powder, much used in dyeing and calico-printing. Chromium, one of the rarer metals, is like platinum in colour, and is about seven times as heavy as water ; it is hard enough to scratch glass, and takes a good polish. It may also be obtained in powder and in scales. It is mostly obtained from two of its ores, which are combina- tions of an oxide of the metal with lead andiron, and from the chromate. Chromium is chiefly valuable for the compounds it makes. The ses- quioxide or green oxide gives an emerald-green colour to vitrifiable substances, and is on that account J CHR useful in painting enamel and porce- lain. The peroxide or chromic acid has a beautiful red colour, and is a powerful oxidising and bleaching agent, useful in calico-printing : when combined with oxide of tin, it forms one of the pink colours used in porcelain-painting. Chromate of potash is a beautiful yellow crystal, obtained by smelting the ores of chro- mium ; when even so little as I part in 40,000 is present, it gives a yellow tinge to water. Bichromate of pot- ash, a red crystal, is manufactured very largely for use by calico-print- ers ; it is made from a solution of the chromate by the action of nitric or acetic acid, and is easily made to combine with several dyes and colours. Chromate of lead is Chrome Yellow (which see;. Chronograph, or time indicator, is a sort of clock which leaves a visible testimony to the lapse of in- tervals of time. In one form of the instrument an observer presses down a small key at the beginning of any astronomical observation, and an- other at the end. Two dots are thus made on a piece of paper coiled round a revolving cylinder; and clockwork connected with the cy- linder enables the distance between the two dots to measure an extremely minute portion of time. A much simpler kind of chronograph has been invented by Mr. Benson, to measure the duration of horse-races, &c., by two little spots of ink which the instrument is made to deposit ; it will measure tenths of a second. Chronometer is a large watch, or small time-piece, made with espe- cial relation to the maintenance of a steady and uniform rate of move- ment. A pocket chronometer, like a watch, is wound up once in thirty hours ; a marine chronometer, 3 to 4 inches in diameter, requires winding up only once in several days, and is also mounted in a mahogany case to keep a uniform position. The greatest skill of Harrison, Mudge, CHR 68 CIG Earnshaw, Arnold, Dent, Frod- sham, Barraud, and other eminent makers has been exercised in insur- ing an equable movement in chro- nometers. The chief difference be- tween a chronometer and a watch is in the provision which the former has for maintaining an equal going, whether the weather be warm or cold. An ordinary watch feels the effects of temperature very much, in the unequal expansion of the metals in summer and in winter. If this were allowed to be the case in a marine chronometer, all the calcula- tions concerning distance and longi- tude would be thrown into confu- sion. The correction is made chiefly through the agency of an expansion balance, which is made of steel and brass soldered together ; the brass expands more than the steel by any increase of temperature ; this in- equality affects the shape of an arc or curved balance, thereby lessening its leverage. When an increase of temperature diminishes the elastic force of the balance-spring, it tends to make the chronometer lose time ; but as the balance also loses power, there is less work for the spring to do ; and thus an equilibrium is main- tained. Exactly the contrary takes place when the' temperature falls, but still with an equilibrium in time. (See also ESCAPEMENT, WATCH, &c.) Chrysoberyl. (See GEMS AND PRECIOUS STONES.) Chrysoprase. (See GEMS AND PRECIOUS STONES.) Churn. (See BUTTER MAKING.) Cider. The chief cider counties in England are Hereford and Devon, in which certain varieties of apple are specially cultivated for the purpose. The making of cider is more simple than that of beer, spirits, or wine. The apples are thrown into a circular stone trough, called a chase, where they are mashed by a stone runner worked by horse power. The pulp, called must, comprising the crushed pips as well as the sotler substances, is placed, interlaid with hair cloths, in the cider-press, where the juice is forced out by heavy pressure. The spent must is wetted and pressed again to yield inferior juice. The juice passes from the cider-press into a flat tub ; then into casks, where it is allowed to ferment to a certain stage. Racking, settling, fining, &c., gradually convert the brown juice into cider, fit either for casking or bottling. Cider is thus really a wine, not a beer ; it requires no use of hot liquor. It contains sufficient alcohol to be intoxicating when taken in large quantities. Having a tendency to turn sour quickly, cider is not well adapted for keeping. Cig-ar Manufacture. Referring to TOBACCO MANUFACTURE for a brief notice of the plant, it will suf- fice to say that particular kinds of leaf are generally selected for cigars. A cigar is a small bundle of frag- ments of leaf, wrapped up in one piece of sound leaf as an envelope. The piece for the envelope is cut into a shape like that of one of the gores of a balloon ; it is laid down flat on a table ; fragments of leaf in sufficient number are laid upon it ; and these, when rolled up in the leaf, form the cigar. A slight screw- ing pinch makes the pointed end ; while the blunt end is cut off square with a gauge to regulate the length. Cheroots are more conical than gore- shaped, and are cut off flat at both ends. Havannah is the most cele- brated name for cigars. Cuba is the island where the tobacco is grown, in large farms maintained for the pur- pose, and Havannah the town where the cigars are made from the leaf. The name Cubas, applied to cheap cigars in England, is nothing but a name ; they are made in England, of cheap tobacco brought from any country. Manilla, a Spanish settle- ment in the East, gives name to the best kind of cheroot. Nearly CIN CLO 3,ooo,ooolbs. of foreign cigars were imported in 1867. Cinnabar is me native sulphuret of mercury. The beautiful red colour vermilion is prepared from it. It is the chief source whence 3netallic quicksilver is obtained. (See MERCURY ; VERMILION.) Cinnamon is the bark of the cinnamon tree of India. At certain seasons of the year the brown bark is stripped off carefully, exposed to the sun, dried till it curls up into small pipes, and then packed in bundles for the market. An oil, a spirit, and a tincture of cinnamon are prepared, useful for several pur- poses. 800,000 Ibs. of cinnamon were imported in 1867. Citric Acid, obtained from lemons, limes, and other fruit, is very useful in dyeing and calico- printing, chiefly in heightening the tints of certain colours. Civet is the name of a powerful perfume obtained from the glands of a tropical animal midway in character between a fox and a cat. The perfume, when pure, is very costly. Claret. (See WINE MAKING.) Clarifying-. This process is il- lustrated in BREWING; VINEGAR MANUFACTURE ; WINE MAKING. Clay, chemically, is a mixture of two earths, alumina and silica, which are themselves oxides of metals. Practically, it presents itself under many different forms. Really pure clay is very little known in the arts, there being nearly always iron, magnesia, lime, manganese, quartz, felspar, mica, or potash occurring with it. The ease with which clay is made up into a dough or putty with water is one of the properties which give it value ; the solidifying of this dough into a hard, durable substance by baking, is another; and the intimate way in which it takes an enduring gloss, in the form of a surface of verifiable glaze, is a third. Hence the important arts of brick and tile making, pottery and porce- lain making, c. The various kinds of clay are each suited for some particular purposes, such as pipe-clay, Stourbridge or fire-brick clay, brick and tile clay, &c. Clepsydra. When water flows out of a hole in the bottom of a vessel, the flow is not uniform, because the pressure is greater when the vessel is nearly full than when nearly empty. If this variation be provided for by mechanical arrange- ments, such a flowing of water may be made to measure time. A receiver into which the water flows may have its sides graduated, or may carry a float with an index pointing to a graduated disc ; and the graduations may be such as to measure hours and fractions of an hour. Such was the ancient clepsydra, or -water-clock. Cliche is a peculiar kind of manu- facture in metal. When type metal, fusible metal, or any kind which melts at a low temperature, is in a molten state, it easily takes an im- pression from a die or stamp. Medals have sometimes been made in this way, and also stereotype casts. The method is useful for obtaining high relief by one blow, which cannot be done" when the metal is cold and solid. The fusible metal, cooled down just to the pasty state, and contained in a cell about the size of the die, has the die suddenly brought down upon it the die itself being quite cold at the time. When well managed, very sharp impressions are . some- times produced by the cliche method ; and casts thus made are now much used as the bases for electrotyping. Clincher-built. In boat-build- ng, clincher-built is when the side planks overlap each other like the slates of a house ; whereas in carvel- built the planks are flush. Clock. A brief description of an eight-day spring clock will convey an idea of this important class of CLO COA time-keepers. Two plates, front and back, confine most of the wheel- work between them. Two barrels contain coiled springs one to give motion to the going train, and the other to the striking train ; con- nected with these barrels are two fusees and an escapement, to give regularity to the movements of the wheels. (See ESCAPEMENT; FUSEE.) The going-train comprises numerous wheels, which work into each other by teeth and pinions, so adjusted that the hour-wheel rotates once in twelve hours, and the minute- wheel once an hour. The striking- train has similar wheels and pinions ; but here the teeth are so regulated in number that a hammer is made to strike upon a bell once an hour. (In more elaborate clocks the quarters are chimed also.) The dial-face, in front of the clock, has the two index-hands placed in con- nection with the going-train, while the bell (usually at the top) is placed in connection with the striking-train. One part of this last-named train consists of a warning-wheel, which produces a peculiar audible tick at a certain interval of time before the striking. The minute pieces of metal Avhich ' ake part in such a clock are so numerous that a bare description of them would be of considerable length plates, pillars, barrels, springs, fusees, escapements, flies, pinions, ? cape-wheels, swing-wheels, pallets, pendulums, clicks, ratchets, screws, pin-wheels, hammers, arbors, pipes, hands, snails, rack-tails, rack- hooks, lifting-pieces, pull-pieces : such are samples of the component elements in a spring clock. A pendulum clock or weight clock derives its power, not from the un- coiling of a steel spring, but from the descent of a weight. From the simplicity of a Swiss clock purchase- able for two shillings, up to the complexity of an astronomical clock used in an observatory, there is an almost infinite variety of modes of construction adopted. Further in- formation will be found under ALA- RUM ; CHRONOMETER; ELECTRIC CLOCK; ESCAPEMENT; FUSEE; PENDULUM ; WATCH. About 250,000 foreign clocks (mostly Ame- rican and Swiss,) were imported in 1867. Cloth.. The principal kinds of cloth or textile goods are noticed under the names of the fibres whereof they are made ; such as Cotton ; Linen, Linen Manufac- tures ; Silk ; Woollen, &c. ; or un- der those of the fabrics themselves. Clothing Manufacture. The making of garments in large esta- blishments is now being organised on a considerable scale by the use of effective cutting-out apparatus, and especially of Sewing Ma chines (which see). Much of the army clothing is made by the Go- vernment on this system. Coach Making 1 . The making of a private carriage, in which England claims to take the lead of all other nations, involves a large number of processes in the working of wood, metal, leather, and other materials ; and the trade is not much degraded by attempts to use inferior materials, or to work them up with defective skill. Although the larger firms undertake the whole of the work, there are numerous subdivisions such us coach-body, carriage, coach- lace, coach - lamp, coach - harness, coach-wheel, and carriage-varnish makers ; as well as coach smiths, platers, beaders, carvers, trimmers, painters, herald - painters , &c. The pattern for a coach is made by drawing and moulding. Every part is correctly drawn to scale, and pattern pieces of thin wood are cut as guides to the shaping of the different parts of the coach afterwards. The lands of wood employed in coach- building are chiefly four ash for the principal parts of the framework ; elm for the naves of wheels, and for the stronger planks COA COA in the body; oak in various parts, for strength and durability ; maho- gany for the panels. Beech, deal, and some other kinds are used to a limited extent, but not in the best coaches. The fow^'-m alters at- tend to all the wood-work of the coach itself, which is the most im- portant and delicate; whereas the carriage-makera manage the opera- tions for the framework which lies beneath and around the body, and which requires much strength. The metal-work of a carriage is varied ; comprising steel springs, side-plates for the perch, the iron strengtheners of various parts, the metal- works of axles, the tires of wheels, the loops and stays, the hoops and clips, the steps and treads, the joints and shackles, the beading and plating, &c., all of which involve careful execution of the numerous processes of working in metal. The leathering Q{ a coach is remarkable work. The roof, and the upper part of the front, back, and sides of a well-built coach, are covered with one piece of leather. It is only the best hide, well tanned and curried, well damped and worked, that possesses the requisite flexibility for this. The hide is worked round the edges and angles without either piercing or pucker- ing, by careful rubbing, pressing, and scraping while wet. The paint and varnish of a good coach are very thick, and of the most per- fect quality. The successive coat- ings of paint are numerous, some- times, indeed, as many as fifteen in number. Frequent rubbings clown occur when the successive coats are dry ; and they are followed by several layers of copal varnish in some parts, of black japan varnish in others. The panels of a highly- finished private carriage present the best specimen, perhaps, which our manufactures afford of paint, varnish, and polish applied to wood. The heraldic painting of such a coach requires, of course, some acquaint- ance with the mysteries of heraldry, and at least an equal familiarity with the use of the pencil, fine paint, brilliant colours, and gold. Omnibuses, cabs, post-chaises, stage- coaches, &c., call for the same class of processes as private carriages, with greater strength in some par- ticulars, but less delicacy of finish . The technical divisions into coach, carriage, barouche, barouchet, lan- dau, landaulet, britzschka, dennet, phaeton, stanhope, tilbury, chariot, tandem, curricle, cabriolet, brough- am, clarence, &c., do not much af- fect the manufacturing processes. The Australian colonies are vying with the mother country in this art. When H.R.H. the Duke of Edin- burgh was at Sydney, in 1868, a landau and a railway carriage were built for his use, nearly equalling in beauty the best of those made in England. Coal. It is not yet quite settled what is the best definition of coal. A lawsuit at vast cost was carried on a few years ago to decide whether a particular mineral was coal or not ; and scientific chemists were arrayed against each other as witnesses in hostile camps. However, coal, as usually understood, is a mineral substance produced by long-con- tinued geological action upon dead vegetable matter ; heat, moisture, and pressure all having been con- cerned in the change. The various kinds differ chiefly in the ratio of bitumen combined with the hard carbon. Anthracite, stone coal, or glance coal, has very little, or even none; while caking coal, pitch coal, parrot coal, cherry coal, splint coal, cannel coal, brown coal, wood coal, lignite, &c., are names for coal which are more or less bituminous, some of them exhibiting a kind of fibrous or woody structure. Caking coal has a tendency to produce fire- damp, woody cozlchoke-damp, while anthracite produces very little of COA 72 COA either. The coal is not one collected uniform mass under the surface of the ground. It is in several strata or layers, with strata of other sub- stances between, the whole being called coal measures. The con- stituents of these coal measures are various kinds of sandstone, shale, day, and coal ; the coal being the thinnest. The strata of coal, called seams, vary from an inch to 30 feet in thickness : all below a certain thickness are too thin to be worked profitably. The coal measures, plus the vast thicknesses of mountain limestone and old red sandstone on which they rest, form the coal forma- tion, as it is often called. The strata of the. coal measures are not always horizontal and parallel one above another ; they are often in- clined often curved, with the con- cavity mostly upwards, like a basin. The edge of a seam of coal some- times bends upwards to the sur- face of the ground, where it forms an outcrop or basset. Fractures and fissures, called faults, dykes, shifts, and troubles, occur in various parts of the coal measures, dislocating the strata and perplexing the miner, who sometimes finds a seam of coal sud- denly gone, he knows not whither. Coal-cutting Machine. To aid the operations of the coal miner, ingenious coal-cutting machines have been invented, applying air power and steam power as auxiliaries to muscular power. One kind, em- ployed at the West Ardsley Colliery, consists of a compressed-air engine travelling upon wheels, and pushed forward by hand to be brought in contact with its work. Above- ground, a steam-engine compresses air into a receiver at a pressure of 50 or 60 Ibs. per square inch ; the compressed air rushes down the shaft in a metal tube, and thence through the horizontal passages, by means of india-rubber tubes, to the workings. The pressure of the air is made by a peculiar arrangement of tubing and mechanism to give a vibrating or backward-and-forward action to the cutting tools, by which the grooves are quickly made which separate the coal into blocks. A cut 3 feet deep and 150 feet long may be made in eight hours. Coal Mining-. A coal mine and a colliery are so nearly alike in meaning that either name may be given. Forming the Mine. Deep shafts or pits must be dug to get at the coal. The shaft is 10 to 15 feet diameter, either square or round, and continued down through all the seams of coal, with their inter- mediate strata of shale, &c. The shaft is for the most part lined with brick-work and with timber-work, called tubbing ; but in some modern pits iron lining has been adopted. Coal is seldom reached, in the northern counties, at a less depth than 150 to 300 feet ; but there are seams worth working at the pro- found depth of 2,000 feet, and the shaft is, in some rare instances, con- tinued to this depth. At each seam, as it is passed through, a lateral passage, calleda bordor mother-gate, is excavated in the seam itself; the ceiling of this is called the roof, and the floor the sill. From the bord other galleries, called headways, are made at right angles to get'at the coal. A main level is also cut for drainage, winding about so as to collect the water from as many different spots as possible. There are many bords made through each seam, and a still greater number of headways to connect them one with another. Each seam is thus cut up into a kind of town of broad streets and narrow lanes, intersecting mostly at right angles. Working the Coal. One mode of digging i's called panel-work. The masses of coal between the passages are panels, and these panels are dug down one at a time. To support the roof where these gaps are left, timber girds or props are set up; and COA COA when it can be done with safety in an exhausted part of the seam, the girds are removed, and the roof falls down in a crumbled heap, forming a goaf. There are, how- ever, cavities thus produced in the mine which too often act as reservoirs for fire-damp. In the thick seam of Staffordshire coal, in many places amounting to 30 feet, a different mode of mining is needed. The miners dig a horizontal channel at the bottom of the coal, called a hole, and stick in small stone props or cogs, and vertical channels to separate the coal into blocks. Some of the blocks are left untouched at the bottom, so as to be stable ; but others are cut into at the sides and bottoms, and have a natural cleavage or parting at the top. Then, the men being removed to a safe dis- tance, a little contrivance brings down a whole block with one crash. Only the lower portions are removed in this way, to facilitate the work- ing of the upper. For another mode of working, see COAL-CUTTING MACHINE. The Miners and their Work. In South Stafford shire, where the ground is honeycombed, the holers or pikemen are the men who cut round the coal at the sides and bottom to separate it into blocks. The bandsmen manage the bands or ropes by which the various kinds of hauling and lifting are effected. The turners-out break the large masses of coal, as they fall, into pieces of reasonable size. The load- ers fill the skips or frames with the coal. The/MZ'fenrbindthe skips round with iron hoops, to keep the coal from falling out. The horse-drivers manage the conveyance of the laden skips on sledges or trucks along the tramways of the bords and galleries to the bottom of the shaft. The hanger-on attaches the skip to the rope or chain which is to haul it up to the surface. The dirt-carriers clear away the ground around the holes. The cleanser separates some of the stony matter which accompanies the coal, and throws it into a heap called the gob. In holing out the lowest stratum of thick coal, and in working thin seams, the miners have to work in a cavity sometimes little more than 2 feet in height; and there, in a cramped, crouching attitude, they have to dig away the coal as best they may. Underground Pas- sages. In the thinner seams, where there is not height enough for ponies or asses to be employed in drawing the trucks of coal, boys are engaged to push the trucks along the tramways ; this is done in some cases where the height of the passage is not more than 2j feet. Some years ago, women and girls were employed in this degrading labour ; but legis- lative enactment has wisely checked the system. Aboveground Works. Coals are brought up the shaft in vessels or boxes of various forms, differing in different districts, and by various applications of steam or water power which need not here be par- ticularised. The safety cage, ap- plicable to the safe raising of coals as well as of men, is separately de- scribed. Some mines have a folding trap-door at the top ; the cage as it rises opens this door, allows it to close again, and then rests upon it ; a loaded hutch or box is removed from the cage, and wheeled along a tramway to a platform ; an empty hutch is put in its place, and speed- ily descends. From the platform the coals fall through an opening into or upon a screen, by which they are screened into large and small. The coals, sorted into kinds, are wheeled away from the colliery on railways, which are either connected with the great railway system of the country, or terminate on some river- side or seaport, where barges and ships are ready to receive them. The owners of the great collieries were desirous, at the time of the COA COB Great Exhibition of 1851, to show what they could do in the way of raising and transportinglarge masses of coal. One block, from Stafford- shire, was nearly 6 feet diameter, and weighed 5 tons ; another, 9^ feet high by 7 feet diameter, and weigh- ing 13 tons, had been raised from a depth of 500 feet; while a third, consisting of anthracite or steam coal from South Wales, weighed no less than 16 tons. Similar masses were sent to the International Exhibition in 1862, and to the Paris Exhibition in 1867. Coal Supply. The coal forma- tions and coal measures are distri- buted very unequally in different districts ; and this has led to the designation coal-field being given to each such district. Those of Great Britain, in round numbers, are sup- posed to cover collectively above 4,000,000 acres. The 4,000,000 acres, however, tell us nothing about the total quantity of coal, seeing that the coal-fields differ both in the numbers and the thickness of the seams. At a particular part of Cumberland there is one workable seam, and one only; in Lanarkshire and in Lancashire there are nearly 80 ; while the aggregate thickness of all the workable seams varies from 3 to 200 feet, and the thick- ness of the workable seams them- selves from 3 to 30 feet. Northum- berland and Durham yield the choicest house coal ; South Wales is the great storehouse for anthracite or steam coal. The extent and rich- ness of our coal-fields are intimately connected with the important ques- tionHow long will our supply of coal last ? In 1866 and 1867 many estimates were given and many discussions held on this matter. The drain upon our stock rose to the enor- mous amount of one hundred mil- lions of tons in 1867, about -^ths of which were used at home, and the rest exported. What ratio this bears to the whole available supply can only be matter of conjecture. Mr. Hull and Mr. Hunt estimate that, if all coal below 4,000 feet depth be rejected as too deep to work, and all seams less than 2 feet thick be re- jected as too thin to work, the rest may perhaps amount to 80,000 million tons. Some computers place the quantity at a higher figure. Coal-tar Products. The refuse coal-tar or gas-tar is becoming of enormous value in the arts. Under GAS LIGHTING an account is given of the mode in which other products besides illuminating gas are distilled from coal in retorts ; and under ANILINE COLOURS those surpass- ingly beautiful colours of the ma- genta class, which are obtained from the tar, one of these products. At first the name of coal-tar was given to the whole of the opaque black liquid which accumulates in the mains above the retorts ; but every year adds to the number of sub- stances which are obtained from it by carefully-conducted chemical processes : crude naphtha, dead oil, pitch, coke oil, pitch coke, re- fined naphtha, benzole, tar, crea* sote, naphthaline, aniline, are all obtained from this source. Cobalt, one of the minor metals in regard to its usefulness in the arts, is, when pure, reddish grey, brittle, a little more fusible than iron, and about 8J times as heavy as water. It is chiefly as a source of blue colours that cobalt is valuable. The protoxide, the basis of smalt, is the most useful form. To make it, co- balt ore is picked, sifted, stamped, washed, and roasted, to get rid of the arsenic and sulphur, &c. When two or three varieties of ore, treated in this way, are mixed, they are called zaffre, and from this zaffre the smalt is made. Silica and pot- ash are brought to the purest prac- ticable state ; and these, pounded to powder and combined with zaffre, constitute smalt. The combination is effected by melting the ingredients coc 75 COC into a kind of glass, removing a scum called sandiver, and a sedi- ment called speiss, pouring the glass into cold water, draining and crush- ing it, sifting and grinding it, and then by repeated washings and sub- sidings separating it into various kinds of smalt, known as azure, farbe, blue sand, and coarse blue. "The singular connection of this metal with blue colour is observable in various ways. The protoxide has a fine blue tint. A compound of this oxide with alkaline salts pro- duces cobalt blue, a colour so beau- tiful as almost to equal ultramarine. The chloride, highly concentrated, gives an intense blue. The phos- phate constitutes Thenardblue, often used in paper-making. Zaffre com- municates a beautiful blue to glass. But it is chiefly in the form of smalt that cobalt furnishes a blue colour- ing agent for porcelain, pottery, stained glass, enamels, encaustic tiles, paper, and paper-hangings. The blues of the celebrated Sevres porcelain are mostly prepared from smalt. A preparation of nitrate of cobalt gives a rose-pink colour. A combination of salts of cobalt with salts of zinc gives Rinman's green. Other salts of the metal, variously prepared, are known as sympathetic inks inks which are not visible on paper until warmed at the fire. Black and violet pigments are also obtained from this singular metal. Cochineal is a Mexican insect, so full ot colouring matter as to be a very valuable aid to the painter, dyer, and calico-printer. When treated by a series of chemical pro- cesses, cochineal yields the beautiful and brilliant colouring substance known as carmine, so invaluable in producing scarlet and crimson tints. We imported no less than 41,00x5 cwt. of these little insects in 1867. Cocoa; Coco; Coca; Cocos ; Cacao. There is a singular confu- sion in the use of these names. A genus of trees, called Theobroma, yields seeds or beans of a very nutri- tious character. The cacao is one species of this genus ; but the beans from it are almost universally known as cocoa. Cocoa-nut, Coco-nut, or Cocos, is a different tree altogether, the kernel of which yields the valu- able cocoa-nut oil. To increase the chance of confusion, cocoa-nut oil from one tree, and butter of cacao from the other, are both employed in making soap and candles. Coca, again, is a different tree, or rather shrub, a South American plant, the dried leaves of which are chewed as a narcotic and stimulant. Cocoa and Chocolate. There is but little difference, in the tech- nical language of grocers, between cocoa and chocolate, they being pre- parations of the same seed or bean. The Theobroma cacao, or chocolate tree, grown abundantly in the West Indies, yields pods or capsules at certain seasons of the year ; and it is the bean, kernel, or seed within these pods that is so nutritious. These beans contain nearly half their weight of fat or oil, butter of cacao, which is employed in making candles, soap, pomades, and oint- ments. The beans, when imported, after drying, are picked, roasted, shaken, crushed, and winnowed ; they then constitute cocoa nibs / and a kind of rind or husk which is se- parated from them finds a sale as an inferior kind of cocoa. In another form the crushed nuts are heated and ground into a paste, to which other substances are added, to en- able water to mix with the fat or butter of the cocoa. These additions are one or more among a large list sugar, honey, treacle, gum, starch, oatmeal, flour, rice, potato starch, nut meal, almond meal, arrowroot, together with spices and perfumes. Mixing, heating, and casting in moulds are the processes adopted. The product is called chocolate if it requires boiling and stirring to dis- i solve, and soluble chocolate it it easily coc COF dissolves. By a change in the added ingredients, chocolate paste is pro- duced. The plain cocoa of the shops is an inferior chocolate, containing some of the husk as well as the bean, and increased in bulk by trea- cle, flour, rice, or other ingredients cheaper than the bean. Flake cocoa is nearly the same as cocoa in pow- der, except in being condensed into flakes by passing through mills. The purest form of all is cocoa nibs; every variety of chocolate, so j called, has other substances added. \ 12,000,000 Ibs. of cocoa and cho- colate were imported in 1867. Cocoa-nut Products. The Cocos nucifera is one of the most useful trees in the world. Under the name of the cocoa-nut palm, it grows abundantly in tropical countries ; and almost every portion of it is brought into use. The root is some- times masticated as a substitute for the areca-nut. The fibres of small roots are woven into baskets. The wood being hard, and taking a high polish, is used for many purposes. The hard woody shell of the trunk has its special uses. The young leaves, are dressed and eaten as a vegetable ; the older leaves are em- ployed as substitutes for cloth in many ways as a thatch, as a mate- rial for baskets and for lanterns, as a plait for hats and bonnets, as a substitute for writing-paper, as a torch, as an oar or paddle, and as a brush. The ashes of the bruised wood and leaves yield potash for soap. The fibrous covering of the blossom is used for cordage and for torches. The flower yields a rich juice, which can either be converted into spirit (toddy] or into sugar (j a gg er y)- J a g er y anc ^ li me form an excellent cement. The nuts, when young, have a pulp very plea- sant for eating, and a milky liquid much relished as a beverage. The older nuts yield cocoa-nut oil, used in making stearine candles and ma- rine soap. The pulp is used to make a kind of preserve with honey or sugar. The husk of the nut is coir or cocoa-nut fibre, of which 6 Ibs. weight can be got from about 40 nuts of average size ; it is one of the best kinds of fibre for cordage, mat- ting, cushions, mattresses, brushes, brooms, &c. Cocoa-nut oil, besides being used for soap and candles, is employed as a lamp oil, as an ingre- dient in ointments and plasters, and as a protector of bottle-corks from the attacks of white ants. The shells of the nuts are used as measures of capacity, as sugar basins and tea- cups, as ladles, as fuel, and as the material for a peculiar charcoal. Of these multitudinous products, cocoa-nut oil alone was imported to the extent of 124,000 cwt. in 1867. Cocoon. (See SILK.) Cod-liver Oil is, if pure, really obtained from the source denoted by the name. Three kinds are pro- duced. Thefiale results from press- ing the livers while in a fresh state ; the light brown from pressing after they have begun to putrefy ; and the dark brown by boiling after the lighter oils have been obtained. Much of the so-called cod-liver oil sold, however, is supposed to be ob- tained from other sources. Coffee. When the beans, berries, or fruit of the coffee tree have been gathered, they are dried in the air and sunshine, pressed between roll- ers to loosen the membrane and the dried pulp, and winnowed to remove these fragments. This is all the manufacture, so called, that coffee undergoes before we import it. The roasting is best managed when the beans are brought to a light brown colour ; they have lost 20 per cent, by weight, but have increased 50 per cent, by bulk ; and the aroma is well developed. Coffee-mills and coffee-pots in great variety have been invented to aid the subsequent pro- cesses. Essence of coffee is a very strong infusion of the bean, thick- ened with chicory and burnt sugar. COG COI 138,000,0x30 Ibs. of coffee "were im- ported in 1867. Cog*. A cog-wheel is a toothed wheel in which the teeth or cogs are not made in the same piece with the wheel itself. Cognac. (See BRANDY.) Coining 1 . Considering that me- tallic coins are practically the stand- ard of value for all retail dealings in civilised countries, and (when symbolised by bank notes) for wholesale dealings also, it becomes very important that the quality, weight, and size of each kind should be reliable. This is the chief reason why the management of the coinage is retained in the hands of the several Governments. The manu- facture involves the use of some of the most beautiful machines and elaborate processes known in the arts. Melting. Each kind of coin, whe- ther, gold, silver, or bronze, is made of an alloy or mixture of metals, for which see MINT. For making sovereigns and half-sovereigns, gold and copper, in proper proportion, are thrown into a crucible, and melted in a furnace of peculiar con- struction. The metal, in a molten state, is poured into a row of ingot moulds, forming a brilliant golden stream during the pouring. The metal for silver coins is melted in a somewhat similar way, but the ingots or bars produced are not all of the same dimensions. They vary from 2 1 to 24 inches in length ; but the bars for gold and silver coins are all alike I inch thick. The sovereign and the shilling bars may be thus compared : ozs. troy. Sovereign 24 X i'375X I m. 320 Shilling . 24 X i'437 X I in. 150 Assaying. The bars are taken hot, but solid, from the moulds, cooled in water, stamped with certain marks, and small pieces cut from each for assaying. (See ASSAYING; TOUCHSTONE.) Weighing. The weight of each bar is next ascertained. Some of the balances now employed for this purpose are of exquisite sensitiveness. One of them, made by Mr. S. R. Short, will turn with I single grain when loaded with I,2OO troy ozs.; and a larger one is proportionately sensitive when weighing 5,000 ozs. Breaking down. This is, in fact, the first rolling process. Each bar is passed between rollers so ad- justed that it becomes lengthened and thinned. They are rolled many times ; as they harden by the pres- sure, they require occasional anneal- ing ; they also require to be cut into pieces as their length increases. Gauging. During the breaking down the fillets are tried in a gauge-plate, to see that their thickness is being reduced in the proper way; and after this they are rolled in a gauge- mill, in which the thickness is mea- sured accurately to within r^ooth of an inch. Flatting. This is another among the very numerous processes of rolling, the fillets pass- ing between exquisitely - adjusted polished rollers of steel or chilled iron. Each fillet is drawn through by an action something like that of wire-drawing, with screw adjust- ments such that ifloVd'gth of an inch can be measured. Cutting out. The fillets, after being tried to ascertain the equability of thick- ness, are sent to the cutting-out press. A punch descends with heavy force, and cuts up the fillets into blanks, the intermediate or waste metal being called scissel. The blanks are cut one by one (for gold and silver coinage), and a workman adjusts the fillets after each descent of the punch. The scissel is thrown again into the melting- pot. Weighing. The blanks are roughly weighed, to see that there is a proper number in a pound weight ; they are examined singly, to see that their edges are smooth ; they are collected into journeys of COI COI 1 80 ozs. of gold or 720 ozs. of silver, and are carried in bags to the weigh- ing-rooms, where a row of Cotton and Pilcher's exquisite contrivances (see GOLD-WEIGHING MACHINE) weigh and classify them. If lighter than proper, they are consigned to the melting-pot; if heavier, they are filed down into mediums by a filing machine almost as beautiful as the weighing machine. Edge Compressing. The medium or proper blanks are rung on a stone by a boy, who can by the sound tell whether any of them are cracked or not. They are then taken to the edge- compressing machine, by which, at the astonishing rate of 700 per mi- nute, the blanks are compressed and thickened at the edge, to prepare for the milling afterwards executed. Coining. The blanks, after the thick edge has been given to them, are annealed in an oven, spread out on a copper tray, turned out into a colander in a cistern of cold water, steeped in hot dilute sulphuric acid, washed under a stream of cold water, dried by sifting in sawdust, gently heated to about 160 Fahr., and are then ready for stamping or coining. The coining-press has the die at the bottom of a punch, and the counterdie (see DIE SINKING) in a recess on a strong plate below. An attendant supplies the blanks, but the machine, by its automatic action, places each in turn on the counter- die, stamps it on both surfaces, and turns it out into a receptacle. The milled edge is given at the same time intended to lessen the chance of dishonest persons clipping or filing the coins. (See further under BRONZE COINAGE ; COINS ; and MINT.) Coins. The sizes and weights of our current coins are regulated by law. 20 Ibs. troy of standard gold is made into 934^ sovereigns ; from which we find that the weight of one sovereign is about 123^ grains or, with decimals in full, 123-2744783306581059 grains. One million sovereigns weigh about 7 tons 17 cwt. A sovereign is 0-8680 inches diameter, and a half- sovereign 0-7622. In silver coinage, the crown, half-crown, and four- pence are no longer made ; the specimens still in circulation were coined several years ago. The silver coins now made are the florin, shilling, sixpence, and threepence. The several kinds bear the following relations in weight and measure : Crown . . Half-crown Florin . . Shilling . Sixpence . Fourpence Threepence inch. 1-5048 1-2714 1-1826 0-9296 0-7648 0-6456 0-6303 grains. 43 6 '4 218-2 I74-5 87-3 43'6 2 9 -I 21-8 The small silver coins called Maundy money stand thus : inch. grains. Fourpence . 0-6957 29-1 Threepence . 0*6383 21-8 Twopence . 0-5294 I4'S Penny . . . 0-4388 7-3 The copper coins (of which none are now made, those in circulation being old) measure and weigh as follows I- inch, grains. Penny . . . 1-3502 291-7 Halfpenny . mS5 145-8 Farthing . . 0-8575 72-9 Half-farthing 0-6953 36-4 The bronze coins, which are now made instead of copper, are con- venient in reference to their dimen- sions ; seeing that the halfpenny is the best practical standard we have for an exact inch, a penny being i inch, and a farthing o-f inch. inch. grains Penny. . . 1-2000 145-8 Halfpenny . roooo 87-5 Farthing . . 0-8000 43-8 There is another useful fact here COI 79 COL to note : a bronze penny is exactly the same weight as a copper half- penny, when both are unworn. Coir, or Cocoa-nut Fibre. (See COCOA-NUT PRODUCTS.) Coke, of immense value as a fue] for locomotives and many kinds o) furnaces, bears some such relation to coal as charcoal does to wood ; it is the solid residue of a kind of distillation. It is made by two methods heaps and ovens. Coke Heaps. Coals are piled up in a heap, with openings left through which fire can be introduced ; and the burn- ing is continued until smoke ceases to rise. The substances given off are smoke, gas, watery vapours, and tar. The heaps or stacks are sometimes made circular, sometimes oblong. Coke Ovens. A better and more economical mode is to employ coke ovens, which vary in size and shape, and are susceptible of being wholly closed or partially opened at plea- sure : several of them are usually so arranged that the heated gases of all may go off into one chimney. The mode of charging and lighting is such that the coal in the oven burns downward, by which all the gases are driven off; in fact, the coal chars or calcines rather than burns. When taken out, the solid residue is coke, more porous and granular, but less glossy, than coal. Good coal yields about 75 or 80 per cent, its weight of carbon ; it loses (say) one-fourth in weight, but gains one- fourth in bulk. Coke produces a great and steady heat, with very little residue. Most of the railway companies make their own coke. It is estimated that, in making 1,000,000 tons of coke, we throw off 1,200 cwt. of sulphate of ammonia to waste every year. CoUieries. (See COALMINING.) Collodion is rapidly coming into use in Ihe arts. It is a peculiar spirit or ether, produced by a rather elaborate process from many che- mical substances. When spread over any surface as a liquid, the" spirituous part soon evaporates, and leaves an extremely thin gummy or glutinous film. This explains the surgical use of collodion in healing wounds, cuts, &c. ; the film shield- ing the part from access of air. When prepared with other chemi- cals, a film of collodion is won- derfully sensitive to light, and is one of the best aids to the photo- grapher, whose pictures are virtually produced upon collodion. (See PHOTOGRAPHY.) Colour Making-. The makers of colours to be used by artists, house- painters, dyers, calico-printers, &c., take the whole range of the animal, vegetable, and mineral kingdoms in their search for materials; and the substances so used may be counted literally by hundreds. Under the names of the colours themselves, or of the substances from which they are made, most of the principal kinds will be found briefly noticed. Colour Printing- consists not merely in printing with coloured ink or paint instead of black, but in combining many different colours on the same sheet of paper. If printed in one colour, it might cer- tainly be designated colour-printing; but the technical meaning of the term is usually polychrome, or many- coloured. There must be a distinct plate, form of type, or stone (accord- ing to the kind of printing) for each colour ; and they must all be so registered or adjusted that each will come exactly in its proper place. If we look at the coloured pictures of the Illustrated London News, we shall occasionally see instances of want of register, one colour en- croaching a little way on the domain of another; generally speaking, however, they are very good speci- mens of polychrome printing. Messrs. Delarue, and other makers of playing cards, have been instru- mental in the development of this COL 80 COM art. Under the superintendence of Messrs. Day, Messrs. Hanhart, and other printers, polychrome printing has now reached a high pitch of excellence. The preparation of the plate, block, or stone is a matter of nicety, in order that the colour should touch that particular one only which is to give the desired tint. Many ornamental productions are printed in gold as well as colours. In this case the plate is wetted with a kind of japan gold-size, a layer of which is thence transferred upon the paper ; leaf-gold is placed upon the gold-size, to which it adheres ; and a bit of cotton wool suffices to rub off the surplus gold from those parts of the paper which had not been wetted by the gold-size. In- ferior articles, such as the labels attached to spun and woven cottons at Manchester, are printed with bronze-powder instead of with leaf- gold. On one occasion a whole edition of 100,000 copies of the Sun newspaper was printed in letters of gold in this way, the so- called gold being really bronze- powder. Colza Oil is obtained by pressure from the seeds of the Brassica oleracea, a kind of cabbage culti- vated in France and Belgium. When of the proper age and con- dition, the plants are cut, and left to maturate for a time; the stalks are threshed; the seeds are win- nowed, sifted, and dried. The oil pressed out from the seeds is much used for lamps, and for lubricating machinery. Comb Making 1 . The materials employed for combs are numerous ivory, tortoiseshell, mother-of-pearl, horn, bone, vulcanised india-rubber, wood, and metals of various kinds. The processes are varied according to the substance operated upon ; but an ordinary horn comb is made as follows : Brought to the form of a plate, and shaped to the proper length and breadth, the piece of horn is ready to have the teeth cut in one edge. Three methods are adopted for this process. (i.) The Double- Saw Method. This double saw has two blades, adjusted to the width of the teeth apart, which is some- times so small as to give 40 or 50 teeth to the inch ; they are of thin steel, with I o to 20 teeth in an inch. When all the cuts are made to the proper depth, the teeth are finished in contour by means of peculiar wedge- shaped files, called floats, grailles, founds, carlets, toppers, and quan- nets strange names derived from the original French designations. (2.) The Circular- Saw Method. Here a circular saw is fixed with the blade at right angles to the length of the comb. A handle brings the comb-plate in contact with the saw ; a tooth is instantly cut by the ro- tating saw, a slight movement draws back the plate, and at the same time shifts it laterally ; and this shifting is exactly equal to the dis- tance from one tooth to another. A second movementof the handle leads to the making of another cut ; and thus the work goes on steadily and quickly. This apparatus is much employed for ivory and hard-wood combs, in which there are some- times as many as 80 or 100 teeth to an inch. Two plates are laid face to face, so that two combs are cut at once ; and if there are two saws also, four combs can be cut at once. (3.) The Method by Parting. By this plan the teeth are cut, or rather pressed out, with very little waste of material an impprtant matter in the case of tortoiseshell, for which the plan is principally adopted. The piece of tortoiseshell is laid down flat on an iron bed ; it is a little wider than the width of one comb, and yet two combs are made out of it. Upon this is brought down a cutter of peculiar shape, something like the entire outline of one tooth of a comb ; it cuts com- pletely through the plate of tortoise- COM 81 CON shell, but does not sever anything nor does it produce any shaving sawdust, or other waste. When th cutting has advanced from end to end, the piece of tortoiseshell parts into two combs the teeth in each having been obtained from the clefts in the other. Compass. This invaluable aic to the mariner consists of a magnel or magnetic needle, delicately poised on a vertical stem. It ranges itselJ in the magnetic meridian, not due north and south, but with a deviation that is always definitely known. The needle supports a circular card, on which the points of the compass are printed ; and the arrangements are such that an inspection of the card will always show the various quarters of the horizon. The needle, the card, and the appendages toge- ther make up the mariner's compass, and the binnacle is the place on shipboard where it is generally kept. Compasses. The compasses for measuring distances generally con- sist of two branches or legs hinged together, one of which has in some kinds provision for a pen or pencil being fixed at the end. They are divided into common, spring, beam, and proportional, according to the mode of action ; while triangular compasses have three legs, to mea- sure triangles. Other kinds are called hair and bow compasses. Compressed-Air Engine. Un- der Hox-AiR ENGINE certain machines are described, in which air in a heated state is used as a substitute for steam in driving wheel-work or mill-work. Other machines employ air in a compressed rather than a heated state. This latter form is adapted for some spe- cial or exceptional convenience, not for economy. At a colliery near Glasgow, one of these engines com- presses or condenses air, drives it down a shaft into a mine, along half a mile of pipe into the mine, up a second shaft, and there works another engine, which pumps and winds be- sides ventilating the workings. To effect these singular results, a steam cylinder (15 inches diameter, 3 feet stroke) works two air-pumps (21 inches diameter, 18 inches stroke), which fill a reservoir with air at 30 Ibs. pressure per square inch. The air enters a main pipe, and forces its way on to great dis- tances, in virtue of the pressure. The engine makes about twenty-five revolutions per minute. Various parts of the apparatus become heated by the condensation of the air, and some of the power is con- sequently lost in the cold water sup- plied to keep the metal cool. It will thus be seen that this is an air- engine really worked by steam. It cannot be cheap in working, but it offers certain facilities whc=re the source of power is required to be far distant from the place of operation. Compressed-air engines of pecu- liar construction are used in working the boring tools for perforating the unparalleled Mont Cenis Railway tunnel, 7| miles long. (See ROCK BORING.) Concertina. (See HARMO- NIUM.) Concrete is one among many varieties of mortar which solidify into a substance nearly as hard as stone. Lime is worked up into a mortar, and gravel or broken stone is mixed with it ; this is in effect the whole process in its simplest form. 3 parts fine sand, I unslaked hy- draulic lime, and I gravel or broken stone form a well-known concrete. Pure lime requires more sand than stone lime. Sharp stones and peb- 3les in the gravel help to bind the mass together. Concrete, so made, s used largely in foundations and underground works, and also as a jacking for coursed masonry. When aid horizontally, it is well rammed as a thick layer. Beton is a name given to concrete which will bear CON the action of water, and is much used in sea and river works. The lime is slaked before being mixed with the other ingredients. It is used, not so much as a mortar or plaster, but as a substitute for actual blocks of stone. In the formation of the great works for the Suez Canal, beton is used in enormous quantity. Condensing Engine. (See STEAM ENGINE.) Confectionery may be regarded as the art of imparting colour, form, and fragrance to sweet substances. The forms which the confections take are lozenges, drops, candies, syrups, rocks, balls, buttons, com- fits, cakes, sticks, jujubes, pastils, bonbons, jellies, jams, preserves, ices, essences, liqueurs, ratafias, &c. The substances employed are sugar, treacle, honey, fruits, seeds, fiowers, spices, together with colouring and fragrant substances in large variety. As a general rule, the confections require only very simple apparatus in making them ; but there are two varieties worthy of a few words of separate notice. Caraway comfits, or sugar plums, each contain a caraway or some other small seed. The seeds are thrown into a copper pan with a mixture of syrup and starch ; heat is applied underneath, and the pan is rolled about in such a way that every seed takes up its own coating of mixture to such a thickness as may be determined. Sometimes the motion of the pan is brought about by machinery. Only comfits of one colour can be made at a time. Lozenges are made of sugar flavoured with peppermint or other essences, and coloured accord- ing to taste. The mixture is worked up like a dough, rolled out flat and thin, and stamped into sepa- rate lozenges by cutters of various shapes. Congreve Lights. (See MATCHES.) Congreve Rocket. (See ROCKET.) 82 COP Coolers ; Cooling. Two modes of cooling large bodies of liquid are often employed, (i.) To allow the Liquid, spread out in a thin layer upon a floor with raised edges, to have fresh air blowing over it. (2.) To allow it to pass through coils of pipes kept cold by immersion in a current of cold water. (See BREW- ING; DISTILLING; VINEGAR MAKING.) Cooperage is the making of vats, backs, tuns, casks, tubs, pails, bowls, and other vessels of wood. Techni- cally, a -wet or tight cooper makes the vessels intended to hold liquids ; the dry cooper makes the looser and cheaper work for holding dry goods ; while the white cooper makes churns and other kinds of highly-finished work. Wet or tight work is made of oak, chiefly Quebec ; many other kinds of wood are employed for in- ferior cooperage. The staves, being curved both in length and in width, are the most difficult parts of a cask to produce. To insure accuracy of workmanship, cask-making ma- chinery has been invented to fashion all the pieces with undevi- ating accuracy; but the hand-work system is still the one most usually adopted. The largest and strongest examples of coopers' work are the enormous vats and backs noticed under BREWING. Copal is a natural sap which exudes from certain trees in Mexico. It comes to us in small rounded masses, pale yellow. Its chief use is in making very fine varnish and lacquer, much employed in the arts. Copper. This valuable metal can be obtained from many different natural substances, but mostly from that kind of sulphuret which is known as copper pyrites or yellow copper ore. When copper is tolera- bly pure it is malleable and duc- tile, may be beaten out into thin leaves, or drawn out into thin wire. It is almost as tenacious as iron. Its density is rather under nine times that COP 83. COP of water, whereas that of iron is only eight times. It melts at about 200 Fahr. at a strong red heat, and passes off in vapour at a white heat. It bears the action of dry air very well, but not of moist. The compounds of copper have immense value in the arts. The oxides impart colour to glass, one red and another green. The sul- phate constitutes blue vitriol, used by dyers, calico-printers, ink-makers, and others. The carbonate consti- tutes blue verditer. The chloride is Brunswick green. Most of the acids described in this work form useful compounds with copper. Copper Mining:. The actual extrication of the ores of copper from the ground is an operation similar to that described generally under MINING, while the rough preparing of the substance obtained is noticed under ORE DRESSING. The copper ore is obtained from Cornwall and Devon, North Wales, and various countries in all parts of the world ; but the great scene of industry, where metallic copper is obtained from the ore by smelting and other processes, is Swansea and its neighbourhood, which may fairly be called the metropolis of the copper trade. The Cornish ores are sold near the mines, and the great firms at Swansea are the chief buyers. These firms send their own assayers as well as buyers. The ore is bought at so much per ton ; and all parties are deeply interested in knowing how much metallic copper there is in each ton of ore. All the lots are tested by samples, and each sample is assayed by the re- presentatives of the various buyers. At a given hour on a given day, a peculiarly quiet sale by tender takes place. The smelters also buy green carbonate of copper, red and black oxides, phosphates and arseniates, as well as copper scales, clippings, and slags, all of which are available as sources of new metallic copper. Copper Smelting-. Supposing a Swansea copper smelter to have obtained his supply of dressed ore (see ORE DRESSING), he carries it through a much more elaborate se- ries of processes than is necessary in iron-smelting. Roasting the Ore. This is necessary to get rid of some of the sulphurets of iron and arsenic. The furnace is of the kind described under REVER- BERATORY FURNACE. The fuel is a mixture of anthracite with small bituminous coal. There may be dif- ferent kinds of ore mixed together, but none of the fragments are larger than a nut. The roasting or cal- cining goes on for about twelve hours, at a temperature which drives off much of the sulphur. It is said that no less than 50,000 tons of sulphur are thus driven off into the air from the copper-works of South Wales, being not only wasted, but a source of sad contamination to the atmo- sphere ; indeed, there is so much sul- phur, arsenic, fluorine, and acid gases of various kinds in copper smoke, that the vegetation of 20,000 acres of land in the Swansea and Neath valleys is almost blasted. Melting for Coarse Metal. Roasted ore and a little copper slag, with some kind of flux, and anthracite and bituminous coal as fuel, are thrown into the coarse-metal melt- ing furnace, which is maintained at a fierce heat. The result of the pro- cess is, that nearly the whole of the copper is collected into a mass called matt, or coarse metal, combined with the residue of the sulphur and iron. Calcining the Coarse Metal. The matt obtained by the last process is in small brownish fragments, con- taining about one-third their weight of pure copper. The calcining of this substance does not differ much from the roasting of the ore. More of the sulphur is driven off by this process ; the substance is reduced to small black grains ; and it now becomes calcined coailed, to separate the seed from the stalk. A kind of large iron comb, called a ripple, is set upright ; the rippler takes a handful of flax, and draws the stalks between the teeth ; the seeds, being unable to pass be- tween the teeth, fall on one side, and are received on a cloth. They are carried away and dried, to be used either for sowing or to yield linseed oil ; while the stalks are tied up in sheaves. Four men can ripple an acre of flax in a day ; but ma- chines have been invented to ex- pedite the process. Retting. The sheaves of flax are then retted or steeped, to loosen the fibre from the boon, or woody part of the stem. This it does by dissolving a kind of glutinous sap or gum. There are four methods of effecting this, more or less adopted. (l.) In dew-retting the whole of the softening process is effected by the moist or dewy action of the atmosphere in a field on which the flax is spread out. (2.) In cold-water retting the flax is put into pools of clear, soft, running water, the sheaves being placed with the butt-ends of the stalks downwards ; a land of fermentation begins after a time, and this is checked when the gum is sufficiently softened, which takes place in a period varying from one to three weeks, according to circumstances. The sheaves are then carefully re- moved from the pool, set up to drain for twenty-four hours, spread out on the grass to receive the action of rain and air, and packed carefully under cover for keeping. (3.) In hot-water retting, according to an invention by Schenck, as conducted by M. Scrive, near Lille, the flax is exposed, for a period varying from three to six days, to a kind of double stream of warm and cold water in a stone tank, with an effect better than that which results from mere steeping in warm water. (4 . ) In steam-retting, as tried by Mr. Watt at Glasgow, the flax is exposed to the action of steam in a close vessel. Breaking. The fibre can now be separated from the boon. The flax break or brake has a wooden lever which presses down on a board ; the under surface of the lever and the upper surface of the board are so fluted or grooved that, when a handful of flax is placed between them, the working up and down of the lever breaks the boon without cutting the fibre. A treadle, moved by the foot of the breaker, works the lever. Scutch- ing. The boon, being thus broken, is driven out from between the fibres by the scutching-blade. This is a broad flat blade of wood, held in the right hand ; while with his left hand the scutcher holds the flax in a notch in an upright wooden stand. By turning about and twisting the flax, nearly all the fragments of boon are driven out. These purely me- chanical processes of breaking and scutching are mostly performed by hand in Russia, Holland, and Bel- gium ; but several machines have been invented for expediting them. Revolving rollers, rotating knives, radiating arms or beaters, whalebone brushes, rotating discs, steel combs, and other familiar kinds of appa- ratus are combined in these ma- chines. The flax, when the boon is thus far driven out of it, is tied up into bundles of 16 to 24 Ibs. each, and sent to market. In this country the chief flax markets are Leeds, Dundee, and Belfast, the three head-quarters of the flax and linen trade. Flax Preparation. The flax-mill, of which Messrs. Marshall's atLeeds, and Sir David Baxter's at Dundee, are, perhaps, the largest and most complete examples, prepares and spins the flax yarns for weaving. The processes of rippling, retting, break- FLA 127 FLA ing, and scutching are performed in the country of growth ; and we have now to follow the scutched fibres to the great mills, where machinery does almost everything. Dividing. The individual fibres, varying from 24 to 36 inches long, have different degrees of fineness at different parts ; they are therefore divided into three, four, or five pieces each, to suit as many different kinds of manufacture. The flax is held between two side wheels, and torn across by the edge of a revolving centre wheel. The action is that of tearing, not cutting; since it is found that the spinning quality of the fibre is injured by a sharp trans- verse cut. Heckling. The heckle, or hackle, is an iron comb, the teeth of which are very sharp, and are placed upright. The heckler, taking a lock of flax by the middle in his right hand, draws each half of the length repeatedly between the teeth of the comb, regulating the posi- tion of the flax with his left hand. This is done first on a coarse heckle, and then on a finer. The combed and straightened fibres are now called line, and the coarser and broken fibres tow. 100 Ibs. of scutched flax produce rather more than 50 Ibs. on an average of line, the rest being tow, boon, and dust. In the larger mills this process is now done by the heckling machine. Heckles or combs are ranged round the circumference of a large cylin- der; the fibres are fixed in a flat layer to a flax holder; several such holders are adjusted to the machine ; and then the rotary action speedily heckles a large quantity of flax. Children are employed to fill and empty, place and replace, adjust and manage the flax holders; all else is conducted automatically. Revolving brushes of bristle clean off any refuse tow from the teeth of the heckles. Sorting. The line is divided by skilful sorters into as many as half-a-dozen different de- grees of fineness, partly by the eye, and partly by the touch ; and each quality is rapidly placed in a sepa- rate compartment by itself. Spread- ing. The fine, glossy, selected fibres are spread upon a feeding cloth, one row partially overlapping another, like slates on a roof. The layer is passed successively between two sets of rollers, which so act upon it as to increase the length and diminish the thickness, converting it to a flat tape or ribbon, but giving it no twist. Drawing. The flax, after the spread- ing, is received in cases, which are conveyed to the drawing frame. This machine combines the tapes or ribbons end to end in one continuous length, women and girls being em- ployed to place them as they are wanted. Roving. Lastly, the con- tinuous sliver of flax goes to the roving machine, where it receives that slight twist which prepares it for spinning. It is no longer re- ceived in cases, but is wound upon bobbins. Flax Spinning*. After the pre- paratory operations of the flax-mill are completed, the fine delicate fibre is ready for spinning. The spinning of flax was for thousands of years one of the recognised employments of women, by the distaff and spindle in the first instance, by the spinning- wheel afterwards. And so it is at the present day in all except the chief manufacturing countries ; but the steam-engine has now led to the introduction of self-acting spin- ning machines for flax as well as for cotton, wool, and silk. Dry fibres of flax do not twine around and form part of one another with the same readiness as those of cotton ; and on this account they are wetted during the spinning. This gives quite a different aspect to the ma- chines, the workpeople, and the room ; there is not that remarkable dryness which is observable in a cotton-spinning room. Cold water was formerly employed for this pur- FLA. 128 FLI pose ; but it is now found that by using water at a temperature of 120 Fahr., the flax is spun finer and more smoothly. The spinning machines are ranged in rows, a trough ex- tends over each row, and warm water descends from the troughs upon the flax. Waterproof aprons are worn by the workpeople engaged at the machines. The yarn, thus spun, is wound upon reels ready for weaving ; or else it is doubled and spun or twisted again to form thread for sewing, lace, &c. Flax "Weaving-. When flax has once been spun into yarn its subse- quent applications are very nume- rous. Some is twisted into thread, for sewing or for lace-making. Some (and this the greater portion) is woven into linen, one of the few staple trades of Ireland. Other flax goods are duck, drill, check, drab- bet, tick, huckaback, diaper, da- mask, towelling, sheeting, dowlas, sacking, sail-cloth; while a much- used combination of flax with cot- ton is called union. Variations in the quality of the flax, the thickness and closeness of the yarn, the mode of dressing, the arrangement and movements of the loom in dressing, and the finishing operations, com- bine to bring about the difference in these several kinds of goods. Jute has lately come into competi- tion with flax for some of the coarser varieties. The weaving operations are sufficiently explained under LOOM, WEAVING, and the names of some of the chief kinds of flax fabrics. Our exports of flax goods in 1867 amounted to 34,000,00x3 Ibs. of yarn, 3,000,000 Ibs. of thread, and 212,000,000 yards of linen and other fabrics. Flax Yarn. The yarn from flax- spinning is made up into leas, hanks, bundles, and bunches. On the larger reels, 120 threads make I lea, 10 leas i hank, 20 hanks I bundle, and 3 bundles comprising altogether 180,000 yards I bunch. On the smaller reels, 100 threads make I half-lea, 10 half-leas I hank, 10 hanks 1 bundle, and 6 bundles, or 360,000 yards, i bunch. The fine- ness is designated by the number of leas to I Ib. ; the finer kinds are from 200 to 400 leas to I Ib. Flint is the most familiar ibrm in which silex is presented to us ; in- deed, flint is almost pure silex. Among the useful applications of this substance, two are gradually becoming obsolete. The flint used with the steel and the tinder-box is yielding to the lucifer match ; while the flint of the gun-lock, in pistols and muskets, is almost su- perseded by the percussion-cap. The use of sharp pieces of flint for knives, axes, daggers, spear-points, arrow-heads, chisels, rasps, wedges, scrapers, &c., by rude nations, has given rise to the speculations of the archaeologists concerning a " Flint Age." The present use of the sub- stance, in its native state, is chiefly in making glass and earthenware. A few of its applications in che- mical solution or combination are noticed under SILICA. Flint Glass. When the ma- terials for flint glass have been melted in the furnace (see GLASS MANUFACTURE), the furnace door is opened, and the workman dips into the golden, glowing, molten glass one end of the blowing tube, an iron pipe 4 or 5 feet long. By dexterous handling, he takes up by the tube just as much glass as will make the de- canter, claret-jug, goblet, wine-glass, or whatever article is to be made. The glass, which has a consistence somewhere between paste and putty, is rolled a little on a smooth slab of iron called a marver; it is expanded by blowing through the tube ; it is gently touched here and there with wooden and iron tools ; it is kept rotating to prevent it from falling off the end of the tube ; and in a way which is scarcely conceivable even to a bystander, it assumes the FLO 129. FLO form of a shapely article in crystal or flint glass. The glass requires to be annealed after it is made. It must be cooled slowly, otherwise the substance will be brittle; and the mode of effecting this cooling constitutes the annealing. The an- nealing oven is called a leer or lear ; it is a very long narrow arch, kept highly heated at one end, and gra- dually colder and colder towards the other. The articles in glass, placed upon iron trays, are pushed into the heated end of the oven ; others are pushed in after them as fast as made ; each tray reaches a slightly cooler region at each movement ; and after many hours the fragile pro- ducts are removed quite cold from the remote end of the leer. Other plans are occasionally adopted ; but this is the usual mode of anneal- ing. What is called cut glass is flint glass of which certain portions of the surface have been ground away, to produce lustrous effects of reflection and refraction. It is really grinding, although called cutting. The tools used are small wheels or discs, rotating with great rapidity. The first action is produced by iron wheels touched with sand and water ; the workman applies the glass to the edge of the wheel, where it is quickly ground down in accordance with a determinate pattern. The second action is with a stone wheel wetted with water ; the third, with a willow-wood wheel touched with pumice or rotten-stone ; while the final polishing is effected on a wood wheel touched with putty powder. The engraving of glass is effected on the same principle as the cutting, but with much more delicate tools, and requiring artistic taste on the part of the workman. Messrs. Dob- son's specimens of engraved glass at the International Exhibitions 1862 and 1867 were among the most exquisite things of the kind ever produced. Floating Battery. This kind of ship was an unfortunate fore- runner of the iron-clad of the pre- sent day. When the Russian war begun in 1854, England and France caused floating batteries to be built, capable of carrying guns of heavy calibre, and of resisting to almost any extent the shot and shell of the enemy. They were vessels of enormous weight, little more than hulks, with solid iron sides. The war was over before they could be used with any effect ; but it is be- lieved that their extreme slowness, and various defects in building, would have soon brought them into disfavour. (SeelRON-CLADS.) Floating Dock. Now that iron- clads are forming an important feature in the navy, the means for repairing them require serious con- sideration. The ooze, shells, sea- weed, &c., which accumulate on the outsides of sea-going ships, im- pede the navigation as well as injure the hull ; and if a vessel were to be brought to England every time a cleansing of the bottom is necessary, great cost and delay would ensue. Hence the utility ot floating docks, a gigantic specimen of which was launched in Sep- tember, 1868. It is called the Betterophon, and is primarily in- tended for docking ships at Bermuda belonging to the West Indian and North American naval stations. It is the largest fabric ever set afloat, except the Great Eastern ; for it is intended to receive any of our iron- clads, and thereby render a kind of service which no docks in the West Indies or in Canada can render. The floating dock is 381 feet long, 84 feet wide inside, 123 feet wide over all, and 74 feet high (or deep). It weighs 8,350 tons, cost^2 50,000, and could lift and carry a ship of 10,000 tons (heavier than any iron- clad ever yet constructed). It has two skins 20 feet apart ; and the space between them is divided into nume- rous water-tight compartments by FLO 130 FLO bulkheads intersecting each other at right angles. Some of these compartments are designated load, some balance, and some air cham- bers. The load chambers are pumped full of water in eight hours, when a ship is about to be docked. Water sufficient to sink the structure low enough to admit the ship to enter is also forced into the balance chambers by means of valves in the external skin. When the ship has entered and been secured, the water in the dock is allowed to decrease by opening sluices ; and then the dock and the ship are trimmed or adjusted by letting the water out of the balance chambers into the structure itself. The inside of the dock is cleared of water by valves in the inner skin. When a ship is to be undocked, after repair or cleansing, the valves in the external skin of the balance chambers are opened, water flows in, and the dock descends sufficiently to allow the ship to be towed out. Altogether there are forty-eight water-tight compartments the fill- ing and emptying of which, or filling of some and emptying of others, enable the monster fabric to increase or decrease the depth of its immersion, so as to accom- modate the entrance, raising, lower- ing, and emergence of a ship. Eight steam-engines and pumps will be employed to pump air out of the air chambers, and water into the load chambers. Large floating docks had previously been built in England, and taken out piecemeal to Cadiz and to Callao respectively ; but the Bellerophon was built with the express intention of making a voyage complete across the Atlantic to Bermuda. Some doubt was ex- pressed whether such an enormous fabric, rising so high out of the water, could successfully encounter bad weather on the ocean ; but her peculiar build leads her constructors to believe that she could hardly sink, even against wind and waves di- rectly ahead . Having no propelling power, the dock must be towed by steamers to the place of destination ; but there is an enormous rudder, to facilitate the maintenance of a proper direction. Like as in the case of the Great . Eastern, the launching of the Bellerophon was in the first instance a failure, owing either to the too small gradient of the launching-ways, or to deficient lubrication ; immense hydraulic power, aided by battering rams, was necessary to make the vast fabric slide down into the Thames. Floating docks of this kind are likely to be made only for localities where there are not good facilities for forming permanent docks of large size. Flock (see PAPER HANGINGS) is made from the clippings of white or coloured cloth which accumulate at the woollen factories. The cloth is stove-dried, ground to a fine powder in a mil], and sifted to different degrees of fineness in a bolting machine. Floor-cloth Manufacture. This convenient substitute for carpet- ing is made of canvas, very thickly coated with oil-paint. For some purposes it is cheaper, for some more durable, and for some more easily kept clean, than woven wool- len carpets. The canvas for floor- cloth is perhaps the widest of all textile fabrics, and the weaving is a special branch of manufacture, carried on chiefly at Dundee. A floor-cloth never wears well if there is a seam in it; and therefore the webs are woven wide enough for any size that may be needed. Some of the canvas is woven in pieces as much as 120 yards long by 8 yards wide, and requires powerful appli- ances in the loom and the weaving processes. Grounding. The pre- paring of the surfaces to receive the pattern absorbs a very large quantity of oil-paint. The canvas, FLO 13* FLO cut up into pieces of convenien size, is temporarily fixed in vertica frames, and kept stretched out by rollers, screws, and weights. Slight platforms are erected, to enable workmen to reach all parts of both surfaces. The canvas is coated with size, and rubbed down with pumice-stone while wet, to level some of the inequalities. A coat- ing of thick paint, without much turpentine, is laid on with a trowel, and scraped well into the fibres oJ the cloth, better, it seems, than if done merely with a brush. Many coatings of this trowel colour are applied to both surfaces, with a long interval between each for drying. The front or best surface is rubbed down with pumice-stone two or three times, and then receives a thinner coating of brush colour, to prepare it finally for the printing. The Patterns. The patterns for floor-cloth are engraved on pear- tree blocks about 18 inches square, backed up with deal, and hav- ing a handle on the back. As this size is small compared with the length and width of the floor- cloth, the block shifts its place scores of times during the printing. Not only so; there must be as many blocks as there are colours, and each and all of these must be worked over every part of the canvas. For the most part, the pattern is en- graved or carved in the wood with cutting tools; but sometimes it is made by inserting slips of copper in grooves, which follow the outlines of certain parts of the device. In all cases the blocks are prepared for surface-printing, not for print- ing on the sunken or copper- plate system. The Printing. The paint for any particular colour is spread with a brush upon a flat cushion 2 or 3 feet square. The prepared canvas, uncoiled from a roller a portion at a time, is spread out on a table ; the printer takes up a block, dabs it face downwards upon the cushion, and transfers the thin layer of paint to the canvas. This is the process, repeated over and over again, with one block and one colour after another, until the whole of the surface has received its due portion of pattern. Small guide- marks are provided to adjust the several adjacent positions of the blocks. The block is held in the left hand, while a short heavy hammer held in the right gives it several smart blows, to transfer the paint to the canvas. Any defective spots are afterwards filled in with paint of the proper colour by means of a hair-pencil. The quantity of paint laid on altogether is so great, and the time necessary to dry each coating so long, that the manu- facture of a large piece of floor-cloth occupies several months. A new kind of floor-cloth is described under KAMPTULICON. Flooring-, as one branch of carpentry, is the laying down of boards close together horizontally, with some -kind of timber support underneath to which the boards can be nailed. Except in relation to inlaid floors (see PARQUETRY), flooring varies in character according to the support underneath, rather than according to the boards them- selves. A single-joisted floor has the boards laid upon parallel joists, which are jointed at the ends into the wall-plates of the house. The "oists are much deeper than they are wide, to prevent swagging ; they are placed about a foot apart ; and if they exceed 8 or 10 feet long, they are strengthened by struts or short nieces extending from one to another. The joists bear the floor-boards on heir upper surface, and on their ower the laths for the ceiling of he room underneath. A double floor, for a larger span, has a kind of upper and lower range of timbers, called binding-joists and bridging- joists, with uprights that connect the one with the other. KJ "ranted floor, FLO 132 FLO for a still wider space, has more tim- ber ; seeing that there are stay-gird- ers 8 or 10 feet apart, binding-joists tenoned into the girders, bridging- joists over and ceiling-joists under the binding-joists, and the floor- boards laid upon the bridging-joists. If the span is greater than one girder can grasp, the girder is trussed, or built up of several pieces, scarfed and bolted in various ways. If flooring-boards are only 4 or 5 inches wide, they are less likely to show the effects of shrinkage than the usual width of 7 to 9 inches for cheap flooring. They vary from i inch to \\ inch thick. Floors are sometimes made of boards without joists, by nailing down two or three layers of boards one on another, crossing diagonally or rect- angularly ; but this is an exception to a general rule. Floss Silk. (See SILK MANU- FACTURE.) Flour Mm. A flour-mill is, at the present day, an exemplification of machine operations on a very complete scale, presenting a striking contrast to the corn-mills of old times. The hand-mill of the East, almost always worked by a woman, consists of two flat stones, of which the upper one is made to revolve on the other by means of a wooden handle and a wooden pivot ; the corn falls down through an opening in the upper stone, and is then, after being crushed into flour or meal, whirled out sideways from between the stones by the centri- fugal force. Europe made the advance from hand-mills to wind- mills, then to water-mills, and now to steam-mills, where the successive operations are almost entirely auto- matic. The order of processes, which varies a little in different establishments, is in substance as follows : Smut Clearing. A self- acting elevator raises the corn to the top of the building, where it passes through the smut machine. A vibrating apparatus keeps the grain in agitation in a wire cage, while a blast of air is blown through it by a fan. This removes chaff, dirt, dust, and small particles which would otherwise injure the white- ness and excellence of the flour ; the refuse is carried away through channels to the outside of the build- ing. The Hoppers. Another ele- vator transfers the cleansed grain to the hoppers, or funnel-shaped re- ceivers, which surmount the several pairs of grindstones. Here a jigging or vibrating motion causes the grain to fall equably between the stones. In some mills a little bell keeps tinkling so long as the supply of grain continues, but stops when the grindstones want more food one of the many ingenious kinds of tell- tale machinery now employed. Grinding. The grindstones, often very ponderous, are so chiselled and grooved on the contact surfaces as to cut and grind the corn very effectually ; the grooves act, indeed, almost like the meeting blades of numerous pairs of scissors. Any required swiftness of rotation may be given to the stones ; they are boxed in, alike to prevent waste and to obviate accidents ; and a blast of air serves at once to blow out the meal or flour, and to keep the stones from that degree of heating which the friction would otherwise give them. So complete are the grind- ing arrangements now in the best steam-mills, that far more flour can be obtained than was formerly possible from a given quantity of grain, the flour itself is better in quality, and the mill is kept clearer from floating dust. Dressing. The flour is taken up by a series of cups attached to an endless band, and conveyed to the dressing machine. This consists essentially of a large, long, hollow cylinder of fine wire gauze, or (for some kinds of flour) of fine silk gauze ; the cylinder is inclined a little lower at FLO 133 FLU one end than the other, and is made to rotate about 650 times per minute. The gauze varies in fineness at different parts of the length of the cylinder. Entering at the higher end, which has the finest gauze, the finest flour passes through the meshes ; then, lower down, flour of the next degree ; and so on to the end, where nothing is left but husk or bran. It is a question of choice with the miller how many kinds he will have of firsts, seconds, pollard, &c., according to the number of variations in the fineness of the gauze. The Sacks. The dressing machines are so placed that the flour falls from them into sacks; and thus is completed the series of operations, in which, from first to last, tne hand scarcely ever touches the grain, the flour, or the machines which contain them. An estimate by Mr. Cola names the sum of 1,1 80 as the cost of apparatus for a mill capable of grinding 150 bushels of wheat in ten hours. The corn elevator, smut machine, clean- corn elevator, and mechanism for delivering into the hoppers, are set down at about ^"90 ; three pairs of grinding-stones, 48 inches diameter, with all the necessary appendages, ^"330 ; flour elevator, double-dress- ing machine, separator, and rotating sifter, ^i 10 ; high-pressure steam- engine and boiler, ^410 ; fan and exhaust apparatus, cranes, and mill gearing of every kind, ^240. A portable flour-mill, with a small portable engine, is now made so low as^ioo. Flowers, Artificial. The art of imitating living flowers in dead substances calls forth a good deal of ingenuity, seeing that the forms, the colours, and the kinds of surface have all to be attended to. All the three kingdoms of nature are applied to for a supply of materials. Wax, feathers, cocoons, shells, silk, satin, velvet, ribbon, whalebone ; cambric, jaconet, muslin, crape, gauze ; gum, resin, paper, vellum, wire are brought into requisition. The Leaves. The pieces to form the imitative leaves are stamped out of green cambric, calico, or taffeta; some glazed and some unglaz.ed ; some with a plain texture, and some woven on purpose. Crimping or wrinkling, glossing with gum, soften- ing of the tint with starch, and forming a sort of velvety nap with wool flock, are the processes of preparing these pieces for use. The Petals and Sepals. These parts of the imitative flower are stamped, with cutting tools properly shaped, out of a much more nume- rous range of material than the leaves. Some of these are gauffered or crimped ; some supplied with imitative veins and ribs by dies ; and nearly all of them tinted by hand, seeing that a flower is seldom of one colour alone. The Buds, Stamens, &c. The little buds of flowers are imitated with small balls of stiffened taffeta, tinted, andstuffed with cotton. Stamens are made either of fine wire, or of thick silk thread stiffened with gelatine. Pollen is imitated by dipping one end of the stamens into yellow flour or dust. The stalk is formed of wire, bound round with green I tissue paper. When these separate parts are ready, the artist builds up the flowers, with the aid of fine wire, thread, paste, gum, &c. Besides imitating natural flowers, the artist makes others of genera and species invented by himself, simply as a means of using up odds and ends. Fluor; Fluorine. Fluorine is one of the simple substances in che- mistry, a gas with which only scienti- fic explorers are familiar. Fluoric acid (fluorine and oxygen) has an intensely biting or corrosive action ; and it is on this account used in various ways in etching and engrav- ing on glass. Fluor-spar, or fluoride of calcium, is a stone with FLY FOO beautifully variegated colours, which cause it to be sought after as a material for vases, paper weights, and other ornaments ; a considerable manufacture of these is going on in Derbyshire, where two varieties of the stone are known as blue-John and Derbyshire spar. It is used also as a flux for copper -ore, and, when dissolved in sulphuric acid, as an etching liquid upon glass. Flux, in metallurgy and manufactur- ing chemistry, is a substance which, when added to another, makes it melt more readily. Borax, fluor-spar, limestone, oxide of lead, charcoal mixed with carbonate of potash, carbonate of soda and potash all act as fluxes for certain metals and ores. Flying Machines. Under BAL- LOONS it is shown that all attempts to control the steering of those vast but light globular masses have hitherto failed ; and the same may be said of the numerous fancifully- shaped contrivances which have been called aerial floats, air- ships, aeromotives, aerial machines, aerial chariots, flying machines, aerial motors, Archimedean balloons, aerial boats, aerostats, cigar balloons, aerial engines, &c. A large amount of ingenuity has in this way been wasted. Birds, fishes, ships, all have been imitated in form, to ascertain whether the power of progression, ascent, descent, and steering could be secured. Flying is really an effect of the moving of the wings of a bird ; and all flying machines, if properly so called, comprise some apparatus or other to imitate wings. But there are other contrivances which belong rather to aerial navigation than to flying ; the machine carrying with it its own motive power, in the form of a small steam-engine or something of the kind. Short distances have certainly been achieved in a few instances ; but nothing of an en- couraging nature has yet resulted. Ply-wheel, in machinery, is a reservoir of force, and also a means of converting an intermittent into a steady and continuous motion. There is some analogy to it pre- sented in the pendulum, the gas- holder, and the air-vessel of a fire- engine. Fog- Signals. (See SIGNALS.) Foil is a very thin sheet of metal, analogous in substance to a sheet of paper. Tin-foil is used at the back of looking-glasses, to form an amalgam with the quicksilver, as a lining for caddies and boxes of various kinds, and as a useful aid in electrical machines. Jewellers' foil, made of copper, tin, silver, or com- binations of two of them, and coloured, is used at the back of transparent gems especially arti- ficial gems to heighten the brilliancy and lustre, and also to form the tinsel of theatrical finery. Some kinds of foil are made by rolling sheet metal to the requisite thickness ; others by forming a solid cylinder of the metal, and then slicing off a film while the cylinder rotates, in the way that ivory veneers are occasionally cut. Jewel- lers' foil is further prepared by colouring, varnishing, and polish- ing. Food, Preserved. Great acti- vity is now displayed in devising means of preserving food in a fresh state, to be eaten long after the time when the animal was killed or the vegetable gathered. The South American beef which excited so much attention in 1865, and the Australian mutton of 1868, serve to illustrate the importance which is attached to this matter. One object is to obtain food from a cheap country for consumption in a country where food is habitually dear. Another is to vary the kinds of food, by obtaining specimens not grown or prepared in our own country. There are three agencies which cause organic substances to FOO FOR spoil and taint by decay heat, moisture, and air. If any one of these three be excluded, dead animal or vegetable food may be preserved for a time. Hence there are three groups of processes adopted, accord- ing to the enemy selected for attack, (i.) Heat. When salmon is packed in ice, it is kept cold, and the fish reaches London from Scotland in excellent condition. The Russians keep their food good throughout the winter by freezing it ; and a so- called freezing process is adopted with some of the Australian mutton intended for England. (2.) Moisture. All the varieties of bacon, ham, dried meat, and dried fish illustrate the fact that the drying, the expulsion of moisture, will lead to the pre- servation of animal food for a great length of time ; and there are many modes of bringing about this result now adopted. (3.) Air. If air be excluded, there is no source for a supply of oxygen, an agent without which decay and putrefaction can hardly arise. This is the fact taken advantage of in most kinds of food preserved in tins, cases, or canisters a method which has given rise to a considerable trade. Most of the processes adopted by Gamble, M'Caul, Hogarth, Leonard, Under- wood, and other preparers of canis- tered food, belong to this third group. It is known as a certainty that meat has been found in good condition twenty-five years after it was canistered. All kinds of meat, fish, and vegetables are preserved in this way, as well as soups, milk, and cream. Another mode of pre- serving is by pickling or salting, as in pickled pork or salt beef. Here the meat is kept more or less in a wet state, the pores being saturated with brine derived from salt. This brine retards the decay of the meat. Dr. Morgan has recently introduced a singular plan of driving brine into the veins of a slaughtered animal before cutting it up into joints. Trusting to his experience as a com- parative anatomist (Royal College of Surgeons, Dublin), he conceived that some of the nutritive juices of meat are driven out and wasted by the ordinary plan of salting or pickling. He therefore devised a mode of forcing brine into all the veins, and thereby salting the ani- mal to the very centre in a short space of time. Forge ; Forging 1 . When iron has gone through the various pro- cesses of smelting, refining, pud- dling, shingling, c., it is ready to De forged into some or other of the infinitely numerous and varied forms required in the practical arts. This forging is a combination of heating and hammering. The forge is the hearth or furnace where the heating takes place, movable or fixed as the case may be ;. and the hammer may be worked by muscular power, me- chanical power, or steam and air power, according to the arrange- ments. Practically, the forging commences when the white-hot iron is subjected to the ponderous blows of the shingling hammer ; but the term is usually applied to a later process. The larger operations of forging are those in which several pieces of iron are welded together into one by repeated blows at a white heat. Such is the mode of making crank-shafts for steam-en- gines and paddle-shafts for steamers, where masses are welded together to the collective weight of 20 tons or more. For smaller work bars are piled or faggoted around a central rod, or fragments of scrap-iron arc enveloped in an old piece of sheet- iron, and then hammered into one piece. In short, there is hardly a. limit to the variety of modes in which many pieces of iron are hammered into one, or a single piece hammered into a particular form. The ordinary open forge or smith's hearth is well known. There is a hearth of brickwork, 5 or 6 feet FOR 136 FOR square : one side is extended to a vertical wall leading to the chimney, the lower end of which terminates in a hood of stout plate-iron. The back wall of iron is perforated to receive the blast from the bellows or blowing machine. This is the larger kind of hearth. The smaller, used for cutlery and small forgings, is raised 2 or 3 feet from the ground, with a hearth about 3 feet square; or, if there are two fires under one hood, the hearth may be 6 feet by 3. There is a trough or compart- ment for water, another for coals, and an ash-pit under the arch ; the anvil weighs from 2 to 4 cwt., and is raised 2 to 3 feet from the ground. There are many forms of portable forge. In one of these, Halley's, the hearth is supported on four iron legs ; the bellows, under the hearth, are worked by a lever handle ex- tending obliquely upwards, and force air up a tube to the level of the hearth. When made portable, the bellows and frames are placed on the hearth ; the pipe and the legs are packed on the top and sides of the bellows ; the hearth and its side plates form a box to contain the various pieces ; and a cover closes down over the whole. Various matters connected with the forge and forging will be found treated in the next article, and under AN- CHOR FORGING, BELLOWS, BLOW- ING MACHINE, CUTLERY MANU- FACTURE, IRON MANUFACTURE, STEAM HAMMER, &c. Forg-e Hammer. Besides the carpenter's hammer, there are the shingling and the #/ hammers, no- ticed under IRON MANUFACTURE and STEELin reference to metallurgic operations. In forging large masses of white-hot iron very powerful blows are needed. These are mostly given now by Nasmyth's important apparatus (see STEAM HAMMER) ; but mechanical hammers of great efficiency are also adopted. In one instance, where the hammer is lifted by the agency of revolving cams, the moving mass weighs 10 tons, the height of the lift is from 1 8 to 24 inches, and the working speed 60 strokes per minute. The helve or hammer-head is of cast-iron, but is faced with wrought-iron. This, pro- bably the largest mechanical or lever hammer ever constructed, was used in forging the great Horsfall 13-inch gun, which weighed 27 tons in the rough. Mr. Waterhouse has constructed a compressed-air ham- mer, for use in light work in a smith's shop, giving 130 blows per minute. Forgery. Some of the precau- tions taken to prevent forgery are noticed under BANK-NOTE MANU- FACTURE. Fork Making-. This process differs from cutlery-work generally in requiring stamping. A rod of steel, heated at the forge, is fashioned into tang, shoulder, and shank, with a piece at one end beaten out flat for the mood or mould. This mood becomes the prongs ; it is heated, and placed in a steel boss or die. An upper die is attached to the lower face of a heavy weight, and by allowing this weight to fall through a height of several feet, the prongs are stamped out of the mood by the cutting action of the die and counterdie, as well as the bosom, or curved part which connects the prongs with the shank. After a little filing, the fork is ready for grinding. This is done on a dry stone, and is very destruc- tive to health. (See GRINDING.) Wire-gauze shields for the mouth, and special ventilation of the grind- ing-rooms, are to some extent adopted ; but the fork- grinders are too often a reckless body of men, regardless of health, earning large wages, and prone to the maxim of leading "a short life and a merry one." The finishing processes by laps, glazers, and polishers (see POLISHING), require much ingenuity FOU FRA to reach all the curvatures and cor- ners of the fork. Foundation, in building, is the establishment of a firm basis whereon the superstructure may rest. It varies according to the softness of the ground and the mas- siveness of the building. If on solid rock, very little foundation is needed. If on sand, a good foundation can easily be obtained when the sand is dry. If on loose shifty soil, it is often necessary to drive in piles to a considerable depth, and lay planks, or 'even beams, on the top of them. If soft, but not shifting, a thick layer of cement may suffice, forming a kind of artificial stone. The lower courses of masonry or of brickwork in a building are often called the foundation. Some buildings, costly r.nd elegant as to superstructure, have lamentably failed on account of want of attention to the founda- tion. One of the greatest works of foundation in England is that con- nected with the new Houses of Par- liament, owing to the size and weight of the structure and the soft- ness of the ground. Pounding-. (See CASTING AND FOUNDING, and the various articles ; relating to working in metal.) Fountains, mechanically consi- dered, and irrespectively of matters ! of taste, are contrivances for causing water to jet up above the natural level of the ground. There are three modes of effecting this : (i), by having a head or reservoir of water at some convenient distance ; (2), by pump- ing up from beneath ; and (3), by taking advantage of a spring at the ground level. The fountains at the Crystal Palace illustrate the first of these methods. When water has once been forced up into the lofty water-towers by steam power, the natural descent of that water by sheer pressure sets to work all the matchless fountains in the grounds. The fountains in Trafalgar Square illustrate the second method, the jets spurting forth only so long as water is being pumped up from beneath. The fountains at many mineral spas illustrate the third | kind, where natural forces give the supply without any aid from steam or other power. The drinking fountains in the public streets act by the same force which drives water to the upper rooms of ordinary dwelling-houses. Fowling-piece. (See SMALL ARMS.) Frame-work Knitting 1 . The making of stockings is the most important of the employments which depend upon knitting, either by hand or by machine. Hand Knit- ting. No description can equal a few minutes' inspection forgiving an idea of the way in, which stockings are knitted by hand. Knitting, Netting, and Crochet are three among many modes of building up a textile ma- terial of a continuous thread with steel and bone needles, and steel hooks, to make some kind of mesh or knot. Knitting Frame. There is a story that William Lee, a Cambridge student, married a poor maiden about 1589, and was *jo reduced in circumstances as to be dependent for subsistence on her earnings as a knitter of worsted stockings. Wish- ing to facilitate her work, he invented the knitting frame or stocking frame, having many iron fingers with which to work. The story may have been coloured by romance ; but there is no reason to doubt that Lee really did invent the knitting frame in or about that year. It is to his credit as an inventor that the principle of the machine has re- mained almost untouched through- out the subsequent improvements. In hand-knitting, loops of thread are formed upon one of two needles, and inserted within other loops laid upon the other needle ; and it was Lee's object to imitate these move- ments by his machine. The frame contains a large number of needles, FRA 138 FRE from fifteen to forty in an inch, placed in a row ; each has a hook at one end which can be tem- porarily pressed down so as to form an eye or closed link, A presser-bar extends over the whole row of hooks ; it can press down all the hooks at once into the form of closed eyes, or can let them remain as open hooks, by the action of a treadle worked by the foot of the weaver. Small pieces of metal called jack-sinkers and lead-sinkers press down the thread between the needles, and facilitate the forming of loops ; while the alternate opening and closing of the needle-hooks enable one row of loops to link in with another. The leads, the -verge, the slur, and the slur-bar are other portions of apparatus which assist in the process. If we unravel a piece of old stocking, we shall see the mode in which the thread loops itself into rows of links ; but it is difficult, even with diagrams, to show exactly by what delicate means the machine effects this. According to the number of loops in an inch, so is the fineness of the work ; and the gauge of the frame varies with these numbers, so that only one degree of fineness can be worked in each frame. This is one among many causes for the dull uniformity of the stocking-weaver's trade ; his frame, if it is his own, will only enable him to do one kind of work. The framework-knitters, stockingers, or stocking- weavers (for all three terms are employed), mostly work at their own homes, or in shops having a small number of frames each not in large factories. If too poor to own a frame, the weaver rents one at so much a week, either from his employer or from a middle- man. Yarn is given out to him from the manufacturer, and he has to return a certain number of gloves, stockings, or whatever the article may be, being paid per dozen for his labour. The seaming or making- up is afterwards done by women. The frame is easy to learn, and thus there is always an influx of young hands, which tends to keep down the wages of labour. Framing. (See CARPENTRY.) Frankfort Black. (See LAMP BLACK.) Frankincense, like turpentine, is a resinous gum that exudes from trees of certain kinds, such as the olibanum, croton, and silver fir. Its chief characteristic is the fragrance which it gives out when burning. Freestone is not in itself a par- ticular kind of stone, but is a name given by the quarryman and the mason to any stone which works freely under the tools. The name applies to some kinds of limestone as well as to some of sandstone. Freezing. Various matters relat- ing to freezing come incidentally for notice under ICE MACHINE, THER- MOMETER, &c. It does not much concern the manufacturing arts, but the fact maybe here mentioned that chemists are acquainted with many freezing mixtures, compounds that will produce intense cold in any substances plunged into them or placed near them. Snow and salt ; muriatic acid and sulphate of soda ; nitrate of ammonia and carbonate of soda ; snow and chloride of calcium ^are examples of freezing mixtures. French Polish. (See VARNISH.) Fresco. Fresco means fresh ; and fresco - painting consists in painting upon fresh or wet plaster. When the rough plaster-work of a wall is finished, a surface of fine smooth plaster is given to it. While this surface plaster is still wet, the artist paints upon it with mineral colours mixed with water. Only as much of the surface is plastered as can be painted the same day, while the surface remains sufficiently damp. There are many difficulties connected with the art : to make the joinings in successive days' work FRI 139 FUL invisible ; to insure that the colour on the wet plaster shall present the proper tints when the plaster is dry ; and to produce a peculiarity of sur- face due to the lime when the plaster dries properly. Friction; Friction Wheels. What friction is, every one knows. It has been ascertained by experi- ment that the friction between two surfaces varies greatly according to the material, although the perfection of workmanship may be quite equal. In oak upon cast-iron the friction is greater than for brass upon cast-iron ; while wrought-iron on wrought- iron is the greatest of the three. Generally speaking, two similar sub- stances have more friction than two that are dissimilar ; soft substances more than hard ; and tables have been prepared showing the relative tendency of various combinations. One mode of lessening friction is by the use of lubricants, such as oil, grease, lard, soap, tar, black-lead, &c. Another is by the use of friction (or rather anti-friction) wheels : this is an arrangement by which the friction on an axle is spread over a larger surface, and rendered less intense at the actual point of working. Fric- tion is not always a defect in ma- chinery; the working of belts, bands, knots, breaks, &c., very much de- pends on the utilisation of friction. Fringe is a work in threads of silk, worsted, &c., in which the com- mon loom is of little use. Braiding, netting, knotting, twisting, and va- rious other processes are employed in rather complex combination. Frit. (See GLASS MANUFAC- TURE.) Fruit, Dried. This term ap- plies in commerce to such fruit as raisins, currants, and figs dried (in the air or in sunshine) in the country of their growth, and packed for ex- portation. Raisins are grapes of various sizes and kinds; the Mus- catel, Malaga, Lexia, Valentia, Smyrna, Sultana, and other sorts, all have peculiarities in regard to the species, picking, drying, and packing. Currants, mostly from Corinth and Zante, are very small grapes, simply dried. Figs, of which the best come from Turkey, are dried either in the sunshine or in ovens built for the purpose. As much as 390,000 cwt. of raisins and 1,000,000 cwt. of currants were imported in 1867. Fuel. (See ANTHRACITE, CHAR- COAL BURNING, COAL, OIL, PEAT, PETROLEUM, SMOKE, &c.) Many kinds of so-called artificial fuel vxt in use, made of various mixtures, in which coal-dust, coke-dust, sawdust, peat, asphaltum, bitumen, pitch, and other ingredients are employed. They are not very extensively used, ex- cept as substitutes for steam-coal on board ship, wherein peculiar quali- ties are needed. The cost of fuel being a direct element in estimat- ing the relative efficiency of steam power compared with other sources of power, engineers are directing at- tention to the capabilities of different kinds of fuel, measured by the quan- tity of water which the heat from a given weight of fuel will evaporate. Fuel Economiser. This is a modern addition to the steam- engine, or rather to furnaces and boilers, which brings into practical use some of the heat which in ordi- nary arrangements is wasted. Seve- ral pipes are placed in the main flue behind the boiler ; water, flow- ing through these pipes, becomes warmed, and is available for supply- ing the boiler, which is thereby fed with some warm in addition to the usual cold water. A curious self- acting appaiatus scrapes off the soot which accumulates on the outside of these pipes, and which would otherwise retard the passage of heat into them. Fuller's Earth, found in vari- ous parts of England, is a soft, grey, greasy-feeling clay, which has the property of removing grease. It FUL 140 FUR used to be always employed in full- ing mills, to remove or loosen the grease from woollen cloth ; in recent times other substances have fre- quently been substituted. Fulling-; Fulling- Mills. In the West Riding of Yorkshire the fulling of cloth is generally con- ducted in different establishments from the spinning and weaving. The cloth is often sold in the rough state at the Cloth Halls in Leeds and other large towns ; and the fulling is then managed at the ex- pense of the purchaser, who may not himself possess fulling-mills, but employs the services of the owners of such mills. At the White Cloth Halls the cloth sold is that which is not dyed till after weaving ; at the Coloured Cloth Halls the cloth has been wool-dyed. Scour- ing. The cloth has been saturated with oil and size before weaving (see WOOLLEN MANUFACTURE) ; and to remove these, it is now scoured. The scouring stocks are heavy wooden mallets or pestles, with which the cloth is beaten in a kind of trough; but they are now partly superseded by the scouring machine, in which the wet cloth is passed and pressed between heavy wooden rollers ; in each case alka- lies and fuller's earth are employed to increase the scouring action. Burling. The cloth, after scouring and drying, is next burled ; that is, it is minutely examined, and all knots or lumps picked out by means of tweezers. Fulling, or Milling. Then comes the fulling, a process unlike anything to which cotton, flax, or silk goods are subjected. The cloth is beaten until the serrated fibres of the threads are thoroughly entangled one among another. The cloth is put into an iron trough with soap and water ; and there it is beaten for a long time with heavy wooden fulling stocks, lifted up and down by machinery. This primi- tive form, however, is being gra- dually uperseded by the frilling machine, in which rollers perform the operation more quickly and eco- nomically than the stocks. Woollen cloth becomes thicker, narrower, arid shorter by fulling. A broad cloth will sometimes shrink from 12 quarters wide to 7, and from 54 yards long to 40, thickening in pro- portion. The cloth is rinsed in clean water to wash off the soapy liquid. What relation fulling bears to the processes which precede and follow it is explained under WOOL- LEN MANUFACTURE. Fulminating 1 Powders are many in kind, all possessing ex- tremely violent explosive power. Some of them are adverted to under the names of the metals, they being usually metallic salts, more or less complex in character. The most energetic, perhaps, is the fulminate of mercury, much employed since the substitution of the percussion- cap for flint and steel in fire-arms. (See PERCUSSION CAP.) One fulmi- nate, made of a mixture of sulphur, nitre, and carbonate of potash, will explode violently when heated to 330 Fahr. The fulminate of silver is another member of this dangerous class of substances. Fumigation is the removal of taint or miasma of any kind by the vapour of burning substances. More | frequently it is merely the substi- | tution of a pleasant for an unplea- ; sant smell, as in incense. One j familiar form is the fumigating pas- til, made up of many fragrant sub- stances, concerning which each manufacturing perfumer has his favourite recipe. Fur; Furriery. Many kinds of fur formerly used in the arts have now become very scarce, owing to the disappearance of fur-bearing animals under the influence of civilisation. The chief kinds known to the furrier are beaver, ermine, stoat, sable, marten, fox, chinchilla, seal, otter, nutria, badger, rabbit, FUR 141 FUS hare, bear, musquath, lynx, minx, and squirrel. The use of felted furs is illustrated under HAT MAK- ING. Some of the finer kinds are used in making artists' hair- pencils. (See BRUSH MANUFAC- TURE.) Dressed furs for garments and coverings undergo many pro- cesses of steeping, scouring, wash- ing, &c., before they are sewed up into form. Furnace. See the names of the chief metals which require smelt- ing, such as COPPER, IRON, LEAD, TIN, ZINC, &c. Also BLAST FUR- NACE, CUPOLA FURNACE, RE- VERBERATORY FURNACE, WlND FURNACE, &c. Fuse. (See BLASTING.) Fusee, in clock and watch work, is a contrivance for equalising the velocity of movement. If the maintaining power be a -weight, a rope or cord unwinds from a barrel as the weight descends, and causes the barrel to rotate. If the main- taining power be a coiled spring, the coil tends to unwind through its elasticity, and to give a rotating movement to an axis or pivot to which it is attached ; but this it does more slowly as the uncoiling goes on, because the force of the spring gradually lessens as the coil becomes less tight. Now the in- genious contrivance of the fusee corrects this inequality in the going of the main-spring in a watch or a spring clock. It is a cone with a spiral groove on its circumference. A small chain is attached at one end to the fusee, and at the other end to a barrel, within which the spring is coiled. When the watch has been wound up, and the spring coiled tightly, the uncoiling of the spring by its own elastic force drags the fusee round through the inter- medium of the chain; and then it happens that, as the spring gets more and more slack and weak, it has a greater leverage lent to it by the varying diameter of the fusee, to such an extent that the elasticity and the leverage are always comple- ments of each other. The two are varying forces, the one increasing in strength as the other diminishes. The fusee is thus made to rotate with an equable motion. A main- taining power, or going fusee, is an arrangement by which the clock or watch is still kept going while being wound up. This is effected through the agency of a circular spring en- closed in the hollow of the fusee wheel. When the watch or clock has no fusee, the maintaining power is supplied by another arrangement of parts. Fusel Oil, a product of the dis- tillery, is an inferior and heavy kind of spirit, resulting when the distilla- tion has gone a little too far. It is- disagreeable in taste and odour, but has been brought into use for some few purposes. Fusible Metal is the name that was proposed by Sir Isaac Newton for a peculiar alloy which will melt at a surprisingly low temperature. Lead melts at about 600 Fahr., bismuth at 500, and tin at 442 ; but a combination of 5 lead, 8 bis- muth, and 3 tin will melt at 200 less than the temperature of boil- ing water. By varying the pro- portions, other degrees of fusibility may be obtained : 2 lead, 5 bis- muth, and 3 tin form one of these varieties. Safety-plugs for steam boilers are sometimes made of fusi- ble metal: before the temperature of the boiler can rise to such a height as to be dangerous, the plug will melt away, and the steam es- cape at. the aperture thus formed. An amusing toy-trick consists in using spoons made of fusible metal : such a spoon, immersed in very hot tea, would melt away, and be found at the bottom of the teacup. Fu- sible metal is usefully employed in taking casts from medals, from the surface of carved wood or embossed paper, and from parts of the human FITS 142 GAS body, even such as the inside of the ear. Cake-moulds for the manufac- ture of toilet soaps are sometimes made of it. Fusing- is but another name for melting. The liquefaction of ice may be called either fusing or melt- ing. Thus 32 Fahr. may be called the fusing or melting point of ice, the freezing or solidifying point of water. In the following list of sub- stances each one fuses or melts more easily than those which follow it ice, tallow, spermaceti, stearine, wax, phosphorus, sulphur, tin; bis- muth, lead, zinc, antimony, bronze, silver, gold, cast-iron, steel, wrought- iron. Fustian is a kind of coarse cotton velvet, having a pile much shorter, and not so highly finished. It is a generic name for a large number of goods, including moleskin, corduroy, velveteen, velveret, thickset, beaver- teen, &c. Most of these are manufac- tured for working-men's clothes. All of them have additional weft thread to form the pile, besides the regular warp and weft. Corduroy has this additional weft thrown in so as to form a corded appearance, an alter- nation of cords and hollows. All the kinds of fustian have the pile cut and sheared like velvet (see VELVET), but there are also pro- cesses of wetting, teaseling, and singeing, applicable only to cotton. Fustic is the wood of an Ame- rican tree much employed in dyeing and calico-printing, producing yel- low colours and combinations of other tints with yellow. G. Galena is the chief source from which lead is obtained. (See LEAD MANUFACTURE.) Galloon is a kind of tape, used for bindings, edgings, shoe-strings, &c., made either of silk or wool, or a mixture of both. Galls; Gallic Acid. Galls are small rounded protuberances found on trees, and caused by insects. Some are quite globular, others more or less oval, from the size of peas to that of nutmegs. There are many kinds in the market, known as blue Turkey, -white Turkey, Aleppo, Mecca, East India, Chinese, and German. All these galls, gall-nuts, or nut-galls, contain gallic acid, which is very similar to tannic acid. This is the acid which renders galls so useful in tanning leather. They are also much employed in dyeing, calico-printing, and ink-making, for producing black. English oak-galls are similar to the rest, but are not rich in gallic acid. Gallic acid, in its purified form, is used in photo- gfaphy, forming salts called gallates. Galvanised Iron is an improper name for iron which has been coated with zinc, and which therefore bears the same relation to zinc that tin- plate bears to tin. Some of the uses of this protected iron are noticed under CORRUGATED IRON. Galvanism; Galvanic. These terms are gradually being super- seded in the arts by Electro, Electric, &c. (which see). Gamboge, or Gamboge, is one of the many kinds of gum or juice exuding from the trunks of trees in warm climates. The gamboge tree, a native of India and Siam, yields this substance in the form of a thick yellow juice, which soon hardens. Gamboge is brought to market in the forms of rolls, pipes, cakes, and shapeless lumps. It is much used as a yellow colour in painting, and in medicine. Garancine. (See MADDER.) Garnet. (See GEMS AND PRE- CIOUS STONES.) Gas. A gas differs from a vapour chiefly in this that the former re- GAS 143. GAS tains its aeriform character at ordi- nary temperatures, whereas the latter more frequently results from heat- ing. The most important uses of gas in the practical arts are con- nected with the production of light and heat. (See the following arti- cles.) Gas Engine. Besides the two modes of applying air instead of steam as a prime mover, noticed under COMPRESSED-AIR ENGINE and HOT- AIR ENGINE, there is a third, in which ordinary gas is used instead of either steam or air. In Lenoir's gas-engine, now much em- ployed in France, the source of power is the expansion arising from the explosion of gas. It is, in truth, an air engine, gas engine, and gal- vanic engine all in one. Air and gas are admitted to a cylinder in the proportion of 1 1 to I ; a spark from a galvanic battery is sent through it ; the spark explodes f he mixture ; and the expansion consequent on this explosion drives a piston to the other end of the cylinder. Mechanism does all the rest opens a slide-valve to afford exit for the exploded mix- ture, drives the piston back by the momentum of a fly-wheel, opens tubes for the admission of new air and gas, establishes connection again with the battery, and prepares for a renewal of the action ; and so on continuously. These engines are costly in the first instance, and many precautions are necessary to prevent them from being overheated ; but they require no stoket, and are rather cheaper to work than steam-engines ; consequently they are much em- ployed for two to four-horse power purposes. Gas Furnace. A small furnace, chiefly for laboratory use, is now much employed, called a gas fur- nace. The burner is so contrived that a stream of common gas is made to give out as much heat as possible, without any regard to the light produced ; just the reverse of the object sought to be obtained in gas-lighting. Various forms of ap- paratus for this purpose have been devised by Bunsen, Griffin, Gore, and other inventors. Gas Lighting-. Every one who sees a little jet of gas burst forth from a heated piece of coal in the fire, sees there a virtual example of gas-lighting; it is spontaneous, but it involves the same scientific principle as the artificial method. Carburetted hydrogen, formed by the carbon and hydrogen in the coal, is a gas or invisible vapour which bursts into flame when heated in presence of the oxygen of the air. The practical problems are how to extricate this gas from the coal, and how to convey it, cold and safely, along pipes to a con- siderable distance. Many artificial schemes were adopted for mere amusement before the commercial aspect of the subject began to be presented. In 1792 Mr. Murdoch lighted up a house and offices with gas at Redruth. In 1802 he illumi- nated the Soho factory of Boulton and Watt in the same way. In 1803 he lighted up two of the cotton- mills at Manchester with gas. In 1812 Mr. Winsor lighted some of the streets of London with gas ; and from that year the gradual extension of the system all over the civilised world may be dated. Gas Manufacture. The manu- facturing processes for street gas are as follow : The Retort House. Coal must not be burned in the open air for this manufacture ; if it were, we should have flame and ashes, instead of gas and coke. The coal is, in fact, distilled in a close vessel, and the gas driven off with- out bursting out into flame at all. The vessels for this distilling (see RETORT) are built up in groups, so that several may be heated by one furnace (there must be fuel also used outside the retort, in order to heat the coal which is inside ; it is only GAS 144 GAS from the latter that the gas is obtained). The best coal for gas- making is boghead, yielding more gas per ton than any other; then come parrot and cannel coal, both of them better for the purpose than Wallsend. Introduced into the re- tort through the mouth, and the door securely closed, the coal be- comes intensely hot, and throws off by degrees atmospheric air, steam, tar, ammoniacal liquor, and a mixture of various gases. These products rise through tubes from the back of the retorts into a vessel called the hydraulic main, whence they pass into other vessels. When the dis- tillation has been carried far enough, the mouths of the retort are opened, the coke (solid residue of the coal) is raked out, water is dashed upon it to cool it, and the retorts are again charged. The Hydraulic Main. The tar and the ammonia mostly condense in the hydraulic main into liquids, and pass off into cisterns. The hot gases pass away into coolers or condensers, consisting of tubes surrounded by cold water ; they give off a little tar and ammonia which they contain, and which would otherwise contaminate them. The Purifier. Having got rid of the tar and ammonia, the next thing is to drive off the carbonic, muriatic, sulphuric, and other acids. This is done by the agency of lime. There are various modes of arranging the purifier and conducting the process ; but the result is that the lime is made to absorb the various acid impurities, or most of them, from the gas. A bushel of lime will purify about 10,000 cubic feet of gas. The Meter. When the gas is quite purified by the above and other processes, it passes through the station meter, which measures the quantity. During this passage it causes a drum or cylinder to rotate ; this sets in motion a train of wheels ; these act upon index-hands which traverse a dial ; and thus the meter tells its own tale as to the quantity of gas which passes through it. The Gasometers. These, which ought properly to be called gas- holders, are the immense vertical cylinders which form such con- spicuous objects at gas-works. Each fasometer is closed at the top, and oats with its open bottom in a tank of water. Some of them are telescopic in their action, to increase the internal capacity without increas- ing the diameter : the vast diameter of 1 60 feet is occasionally given to them. The substance is sheet-iron, tarred within and without, and strengthened in various ways with iron rods. Balance weights and chains enable the gasometer to float in the tank of water, and to rise in proportion as the gas accumulates in the inside. The water is to pre- vent any leakage of gas. The tend- ency of the gasometer to descend by its actual weight produces a con- densing pressure on the gas within, and this pressure tends to drive the gas through miles of street pipe. G-as Pipes and Burners. The distribution of gas through the streets of a town, and the arrange- ments for burning it, call for the use of a large amount of metal piping. The Mains and Pipes. The mains which proceed from the gas-works are large in diameter ; those through the minor streets smaller ; and those into the houses smaller still. The larger pipes are of cast-iron, in pieces 9 or 10 feet long, well jointed and luted. As some districts re- quire more gas than others, as more is required in winter than in summer, as there is a large and sudden demand every day just as night closes in, and as there is always less demand on Sundays than on week-days, a vast amount of consideration is needed in storing a sufficient quantity, and in making the pressure vary with the demand by the aid of pressure indicators and self-acting governors. The smaller pipes, to convey the GAS GAS gas into house's, are olten of lead or pewter. The Meter. The arrange- ments for enabling the company to know how much gas the consumer has burned are noticed under METER. The Burners. A gas- burner is nothing more in principle than an orifice, or a row of orifices, through which the gas escapes from the pipe, to be burned as -a jet; but as the object in view is to cause every atom of gas to produce flame, much ingenuity has been displayed in so arranging the orifices as to attain this end. If contact with the external air is not sufficiently com- plete, some of the gas will go off in a non-luminous state, either as invisible gas or as smoke. Various arrangements of the orifices give rise to forms of burner which receive the names of \hefish-tail, cock-spur, union, bat-wing, fan, swallow-tail, &c. The glass chimney, generally used around and above the flame, regulates the mode in which the air gets access to the gas ; and the numerous forms given to it are indi- cative of the large number of experi- ments which have been made on the subject. No burners can work j really well unless some provision is made for carrying off the products of combustion. (See VENTILATION.) G-as Products. In making gas on a large scale for the supply of streets and buildings, provision has to be made, not only for the extent of demand for gas, but for getting rid of many other pro- ducts of the manufacture. When the gas has been made, the solid residue (see COKE) has a ready market as fuel : it is produced in the ratio of about one chaldron (1,494 tt>s.) from every ton of coal. There are also produced 12 gallons of tar and 12 gallons of ammoniacal liquor. About one-fourth of the coke is used as fuel for heating the retorts, and the other three-fourths sold. The tar (once a nuisance to the companies and their neighbours finds a ready market for making paint, creasote, patent fuel, naphtha, pitch, aniline colours, and nume- rous other useful substances. The ammoniacal liquor is employed in making sal ammoniac, carbonate of ammonia, &c. For the employment of other fuel than coal, see OIL GAS. G-as Stoves. Cooking and heat- ing by gas are becoming everyyear more familiarly known not that they are better than all other methods, but that they are con- veniently employed under some circumstances. Asbestos Stove. One of these contrivances depends on the use of asbestos, a substance which may be brought to a white glowing heat without actually burn- ing or consuming. A kind of grate is formed, with hollow tubes instead of iron bars ; the tubes communi- cating end to end, and being ranged parallel, further back at the upper rows than the lower. The tubes are gas-pipes, and small perforations in them serve as jets. The gas might simply be lighted in this form, producing a stove of minute jets of flame ; but this would not imitate the appearance of an ordinary open fire. The grate is therefore filled up with asbestos shavings, which soon present a dazzling mass of white-hot fire, with gas flames dart- ing up through all the interstices. This of course requires that the stove should be made on purpose, and that the tubular bars should be placed in connection with the gas- pipes of the house or factory. Ward's Stove has a row of gas jets near the bottom of an iron case roomy in length and breadth, but very shallow Irom front to back. It is not an open fire-place, but a close stove, which heats a large surface of sheet-iron by the con- sumption of a small amount of gas. Graham's Stove has a considerable length of gas-pipe, twisted about in horizontal coils a little below the upper horizontal plate. The coils GAS 146 GEL are so placed that immediately over them the plate can be opened, and saucepans and vessels of various kinds exposed to the direct ascensive heat of the gas, issuing in numerous ignited jets from holes in the pipe coil. Some of the coils are made applicable for roasting, some for baking, some for heating water in a boiler; and the action of all the coils is governed by appropriate stop-cocks. Gas Tar. (See ANILINE COLOURS; COAL-TAR PRODUCTS.) Gauge; Gage. A gauge is an instrument for measuring dimen- sions, direction, and intensities of different kinds. One sort, much used in metal manufactures, is an imple- ment of steel or brass, with a cleft widening from one end to the other : when metal wire, sheet, or plate is inserted in this groove, graduations serve to denote the varying thick- nesses. Another kind is a piece of steel, with notches of different sizes at the edge. Wires and sheets are denoted by numbers ; but manufac- turers have not yet agreed upon any uniformity of meaning to attach to those numbers : wire No. 20 in Lancashire is not the same thick- ness as wire No. 20 at Birmingham ; nor is sheet-brass No, 20 at Bir- mingham the same in thickness as sheet-iron No. 20 at the same place. Mr. Whitworth is trying to induce manufacturers to adopt a gauge- scale in which the name shall at once denote the thickness. This would entirely get rid of the present discrepancies between Birmingham gauge, Lancashire gauge, "wire gauge, sheet-iron gauge, sheet-brass gauge, plate gauge, rod-iron gauge, nail-rod gauge, button-makers' gauge, &c. (See further under WIRE.) Gauger; Gang-ing:. A gauger keeps the Excise department in- iormed of the number of gallons of exciseable liquor contained in the casks. He ascertains this by gaug- ing or measuring the casks in vari- ous ways, with the aid of sliding scales graduated on a particular system. Gauze. In the ordinary pro- cesses of the loom, the warp threads are always kept parallel, in what- ever way the weft threads may be twisted around them. But in mak- ing gauze two adjoining warp threads are completely twisted round each other between two throws of the shuttle or casts of the weft. Some peculiar appendages to the loom are required to effect this. One consequence of the mode of in- terlacing is, that the texture is light, the weft threads being further apart than would be practicable in other webs. In appearance, as well as in mode of producing, gauze occupies a kind of medium position between plain weaving and plain lace or bob- bin net. Gearing. When one part of a machine communicates motion to another by means of toothed wheels, friction wheels, bands, &c., the ar- rangement for doing this is called gearing ; and the parts can be placed in gear or out of gear by a simple adjustment in the kinds known as movable gearing. According to the direction of the motion commu- nicated, the gearing is either straight or bevelled; the latter being illus- trated by bevelled wheels. Gelatine. Besides such sub- stances as Glue and Isinglass (which see), there are now made many useful forms of material known simply as gelatine. Thin skins and membranes, hide-parings, bones of small animals, calves' feet, &c., are employed to produce it, by boiling and other processes. It usually comes to market in cakes of various sizes ; but very beautiful sheets of coloured gelatine are also made for ornamental purposes. The chief feature in this manufacture is, that it profitably uses up substances which were formerly much liable to GEM 147 GIL be wasted. Animal tissues ; the waste residue of parts of animals which have served for food; the waste from tanneries, from manu- factures in bone and in ivory all are available. One reason why the French have made so much advance in the manufacture of gelatine is, that there are in that country well- arranged and systematic establish- ments for the slaughtering of cattle, sheep, swine, and horses ; affording great facilities for the economical ap- plication of the hides, skins, bones, tendons, ligaments, and other gela- tinous tissues. Not only do the French excel in producing large sheets of transparent gelatine, co- lourless or brilliantly coloured, but they also emboss or stamp them with elegant designs. There is a distinction made between two kinds of gelatine the one gluten, ob- tained from the skin, tendons, and bones of the adult animals ; and the other chondrin, obtained from the bones and cartilaginous tissues of young animals. Most kinds of gelatine are obtained from the first of these two sources. Gems and Precious Stones. These costly articles are not much used except for ornament : diamonds for cutting glass and for lapidary work, diamonds and rubies for jewelling watches, small bits of gem for microscopic lenses, are ex- ceptions. The more costly are known as gems, the less costly as precious stones; but there is no precise line of division between the two groups. They display among them every colour of the rainbow, and very varied degrees of hardness. The hardest of all is diamond ; then come sapphire and ruby; then topaz and amethyst ; then agate, beryl, emerald, garnet, onyx, sardonyx, chalcedony, and so down to turquoise, opal, &c. Other names of gems and precious stones are carnelian, jasper, hyacinth, carbuncle, lapis lazuli, chrysolite, chrysoprase, tour- maline, obsidian, bloodstone, aqua- marine, cafs-eye, heliotrope, cairn- gorm. For the working of gems and precious stones see LAPIDARY WORK. Gems, Artificial, or paste jewels, are made chiefly of a peculiar glass called Strass (which see). Several accomplished French chemists, es- pecially Deville, Despretz, Caron, and Becquerel, have had some suc- cess in researches for producing, not mere imitative gems, but real gems by artificial means ; they have really made diamonds, rubies, sap- phires, and opals out of the che- mical elements which compose those gems. Geneva, or Hollandses the kind of spirit mostly distilled by the Dutch, and flavoured with juniper berries. At the Schiedam distil- leries unmalted rye is mixed with malted barley. German Silver. The relation which this alloy bears to others of somewhat similar kind is noticed under BRITANNIA METAL; WHITE METALS. German Tinder. (See AMA- DOU.) Ghee is prepared by the Hindoos from the milk of the buffalo, by boiling, cooling, coagulating, churn- ing, and potting for use. It is used by the natives as butter, but is dis- tasteful to most Europeans. Gilding-, Leaf, is the impart- ing of a surface of gold to a sub- stratum of wood or other sub- stance. Here gold leaf is employed, not upon the wood, &c., itself, but upon a composition previously applied to the wood. This compo- sition is mostly a mixture of pounded whiting with size made from parch- ment cuttings ; it is used hot, and is applied with a brush. In gilding the frames for looking-glasses and pictures, intermediate between many coatings of this composition various tools are used to smooth the surface, and to preserve the contour and GIL 148 GIN ijharpness of the mouldings. Many of the ornaments of such frames are made of a composition of glue, lin- seed oil, and wniting, pressed while having a putty-like consistence into moulds, and afterwards affixed to the wood chiefly by glue : these ornaments do not require so many coatings of whiting as the wood itself. If the work is to be bur- nished gold, a peculiar mixture of pipe-clay, red chalk, black-lead, suet, bullock's blood, and parchment size, called burnish-gold size, is applied in several successive coatings ; but if it is to be oil gold, the gold size employed is of an oily character. The gold leaf is blown out of the books (see GOLD BEATING), cut into pieces of various sizes on a lea- ther cushion by means of a smooth- edged knife, and applied by a flat camel-hair brush. The burnish-gold size requires to be wetted with water; but the oil-gold size is gilt when slightly damp and adhesive. After many niceties of detail, to in- sure the perfect covering of every part with gold, that which is to be burnished gold is rubbed with a smooth agate or flint burnisher, ex- cept the parts which are to be matt or dead. Nothing further is done to the burnished surface; but the matt as well as the oil-gilt re- ceives a coating of clear warm size. Paper and other substances may be coated with gold leaf by modifi- cations of these processes. Gilding-, Metal. Metal Gild- ing, more familiarly known as water gilding, is a chemical rather than a mechanical process. The article of metal, whether a button or anything else, is thoroughly cleansed in some acid solution, washed, and dried. An amalgam is made by dissolving leaf-gold in about ten times its weight of mer- cury, heating and stirring it, strain- ing it through wash-leather, and forming with nitric acid a liquid. The articles of metal are either dipped into the liquid or brushed over with it, thereby acquiring a dull whitish appearance. Exposure to the heat of an oven drives off the mercury, and leaves the surface of a golden colour, but dull and un- finished. A burnisher of bloodstone polishes some parts, while a lacquer imparts a peculiar frosty deadness to the rest. The coating of gold thus laid on is extremely thin. Some of the coat buttons gilt by this method have only two or three grains of gold to a gross. The metal on which water gilding is effected is purposely made somewhat of a golden colour by a peculiar proportion of coppei to zinc in the brass. Gilding-, Miscellaneous. There are many other kinds of gilding adopted in the arts such as japan gilding, in which japan-gold size is used ; bronze gilding, by a peculiar use of bronze powder ; cold gilding, in which certain solutions of gold are rubbed on with a piece of cork, or applied with a camel-hair pencil ; porcelain gilding (see ENAMEL ; PORCELAIN) ; immersion gilding, by dipping articles of metal in a hot chemical solution of gold ; electro- gilding (see ELECTRO METAL- LURGY) ; and textile gilding, by dip- ping the articles in certain solutions. Most of the gilt toys and trinkets now made at Birmingham are of stamped copper, electro gilt. Gimp is a trimming of silk, wool, or cotton, in which fine wire is twisted among the threads. Gin. There are three meanings of this word in technology, (i.) A gin is a machine for opening the tufts of cotton after gathering. (See COTTON GIN AND GINNING.) (2.) Aginisz machine for raising weights, or for communicating motion by means of poles, pulleys, rods, a windlass, &c. (3.) Gin, in distilling, is the sort of spirituous liquor usually made in England. It may be produced from barley, oats, or wheat, malted or unmalted, in the same manner as GIN 149 GLA whiskey ; but there the resemblance ends. Real Irish or Scotch whis- key is very little "doctored" after the distilling; whereas gin, in the hands of the rectifier, is so treated with fruits, berries, seeds, flowers, or leaves, and with sugar, as to ac- quire an artificial flavour. The dif- ferences between Hodges', Smith's, Nicholson's, Booth's, Bristol, Ply- mouth, and other kinds of gin, de- pend more on the rectifier than on the distiller. Ginger, as a spice, undergoes very little preparation for the mar- ket. It is the root-stock of the East Indian ginger tree : taken up when the stems wither, this root- btalk is scalded, dried, scraped, and washed. Ginger beer is simply a fermented and effervescing beve- 1 age flavoured with ginger ; ginger \vine, a home-made wine similarly flavoured ; and gingerbread , a cake of flour, butter, and sugar (or treacle), lightened with tartrates and carbonates, and spiced with ginger. Our imports of ginger in 1867 were 830,000 Ibs. Gingham is a cotton cloth much used for umbrellas and other pur- poses. Some kinds are plain, or in one colour ; while others have two or more colours woven in the" loom, in the form of stripes, checks, and diapers. Girder, as a main beam, placed horizontally to support a great weight of superstructure, was origin- ally really a beam in one piece ; but large spaces are now spanned with trussed and lattice girders of wood, of cast-iron, and of iron plates riveted to form a boxed or hollow girder like those used so abun- dantly in the Charing Cross and Cannon Street Bridges of the South- Eastern Railway. Glass Manufacture. Glass is cer- tainly one of the most beautiful of all manufactured products. The chief kinds are BOTTLE GLASS, CROWN GLASS, FLINT GLASS, OPTICAL GLASS, PLATE GLASS, SHEET GLASS, and STAINED GLASS. These are described under their proper headings, as are also certain minor kinds under AVENTURINE ; BEAD MANUFACTURE ; ENAMEL ; and STRASS. It will suffice here to notice certain general matters which apply to all of them equally. All glass contains silica, the most fa- miliar forms of which are flint and fine sharp sand ; all contain either soda or potash, or both ; and some of them contain alumina, lime, oxide of lead, or oxide of iron. By ring- ing the changes on these alkaline and metallic oxides the various kinds of glass are produced. Silica will melt in combination with them ; and the molten mixture, when cooled, becomes transparent. More soda or potash renders glass more fusible ; more lead increases its brilliancy and refrangibility ; more lime or alumina increases its hard- ness ; more iron increases its green colour for bottle glass. For different kinds of glass, silica is obtained in the forms of flint, Alum Bay sand, Lynn sand, Reigate sand, &c. All the other ingredients are now ob- tained very cheaply from the manu- facturing chemists. The different kinds of glass vary from two and a half to four times the weight of water. Whatever the materials, they are converted into frit, a powder usu- ally of a salmon colour. This con- sists of a thoroughly-mixed com- bination of all the substances in proper proportions. A glass house is usually a circular building, 40 or 50 feet diameter at the bottom, and diminishing conically upwards to a height of 60 or 80 feet. The furnace is in the middle of this building, cir- cular in form, and of sufficient size to admit eight to twelve large melting- pots. Doors in the wall of the fur- nace give access to these pots ; and the low-domed roof causes the heat to be reflected down upon them. These pets are made of weil-pre- GLA GLO parcel and well-annealed clay; some of them are 3 feet wide, 4 feet high, weigh 10 cwt., and will contain 1 6 to 20 cwt. of glass. They are closed on all sides, except a projecting mouth near the top of one side. The frit is thrown into the pots through the furnace doors ; the doors are closed ; the heat is urged to the high- est point ; and then the frit, melted into a golden liquid glass is ready for use. Our exports in 1867 were 963,000 cwt. of window, flint, and bottle glass, and 950,000 square feet of plate glass. Glass Paper is like emery pa- per, except in the substitution of powdered glass for emery. (See EMERY.) Glaze. The best way to regard the glaze of porcelain and earthen- ware is as a true glass burnt into the surface of the ware. This sort of glass is not absolutely necessary, seeing that some nations have suc- ceeded in making pottery imper- vious to water by a coating of tallow, afterwards charred ; others by a black varnish ; others by wax ; but glaze is certainly the cleanest and best of all. For coarse ware the glaze usually contains oxide of lead ; for fine ware, oxide of tin ; for cer- tain special kinds, earthy oxides. As the glaze must not only render the ware impervious to water, but must be transparent, lustrous, and durable, its composition should bear some definite i elation to that of the substance whereon it is applied ; and this is attended to in practice. Me- tallic and earthy oxides, salt, potash, borax, baryta, phosphate of lime, silica all are used in some or other of the kinds of glaze. For special kinds of ware the glaze is required to be either slightly opaque or slightly tinted ; and the ingredients are selected accordingly. The chief materials in ordinary earthenware glaze are salt and borax. The dry ingredients of the glaze are ground to powder and mixed with water; and, in the majority of instances, the ware is simply dipped into this cold liquid. (See PORCELAIN, POT- TERY, &c.) Pottery-glazing used to be an unhealthy employment when oxide of lead was much used ; but borax is now substituted, producing a whiter, harder, and less injurious glaze. Glazing-. There are several modes of applying this term in the arts, (i.) Glazing is the use of the liquid glaze just described for earthen and porcelain wares. (2.) Glazing is the polishing of metals by means of small wheels or discs covered with some polishing sub- stance. (See CUTLERY MANUFAC- TURE.) (3.) Glazing is the impart- ing of gloss to woven fabrics, as in Calendering (which see). (4.) Glaz- ing is the work of the glazier ; cut- ting pieces of glass to definite sizes and shapes, and fitting them into windows by means of putty, &c. Globe Making. There are many curious processes involved in mak- ing a terrestrial or celestial globe. (I.) The engraving for the surface must be in pieces sufficiently small to cover the whole globe ; and this requires a nice measurement and shaping of the gores or lens-shaped pieces. (2.) A ball of wood or metal is made, which may serve as a mould for any number of globes of the same size. (3.) Successive layers of paper are shaped upon the ball to the thickness of cardboard, but the innermost layer not pasted upon the ball itself. (4.) The paper is cut along the equator into two halves, and then removed. (5.) The two hemispherical shells are placed together, with an axis running through, and connecting them into a globe. (6.) The surface is coated with a composition of whiting, and made true and smooth. (7.) The engraved pieces of paper are pasted on in their proper places. (8.) The varnishing and finishing processes depend on the costliness and style GLO GLY of the globe. Special globes of glass, paper, india-rubber, and gutta percha are made for various educational purposes. Glonoine Oil. (See NITRO- GLYCERINE.) Glove Making- is still a handi- craft employment. The various kinds of leather, and the various fabrics of silk, worsted, flax, cotton, &c., are prepared for, but not by, the glove manufacturers, whose work consists in cutting out and sewing up. So-called kid gloves aremostlymade of lamb-skin: so-called dog-skin, of buck-skin; and doe-skin gloves are mostly made of sheep-skin ; but some are really made of the leather denoted by the name ; others from calf-skin. The cutting requires much tact to get the most out of the material, and to employ the best parts in the most conspicuous places. Kid-glove making is the choicest of all; and in this the French so excel, that 400,000 dozen skins are annually made up into kid g]oves in that country. In. some instances, templets and punches assist in cutting out the glove pieces. In England, Worcester, Yeovil, and Woodstock are the centres of the leather-glove trade. The textile gloves are made in various places, according to the material. Some oi the stocking and knitting ma- chines have been so adjusted as to make gloves with very little sewing to do. England largely imports gloves, chiefly French 11,000,000 pairs in 1867." Glue Manufacture. This very useful form of gelatine is obtained from the parings of hides and skins, chippings from hoofs, ears, and tails, and various refuse matters from the slaughter-houses, tanneries, fell- mongers', and furriers' operations. Many processes are concerned in the manufacture steeping in lime- water, rinsing in a stream of clear water, drying on hurdles, placing in a large network bag, and boiling until the gelatine is extracted. The gelatine, when boiled to the proper strength, is transferred to a settling vessel, where it remains till, by the addition of fining or clarifying ingredients, it has got rid of all impurities, and has become good glue. The glue is run off into coolers, cooled to a jelly, cut by a spade into square cakes, cut into slices by a brass wire, dried upon nets in the open air, and finished by stove-drying. The gelatinous sub- stances which are boiled in the first instance are boiled a second and third time, to produce size for painters, plasterers, paperhangers, c. ; the refuse becomes available as manure. Glue, Marine, invented by Mr. Jeffery in 1842, is a very tough cement for wood, well adapted for marine and hydraulic purposes. It consists of india-rubber, coal naphtha, and shellac, in the propor- tion of I Ib. of the first and 4 gallons of the second to a small quantity of the third. It is said that two pieces of wood cemented with this glue become stronger than one entire piece ; and many experiments made by the Admiralty tend to confirm this statement. This marine glue is also used as a substitute for pitch in paying the seams of ships. Gluten is one of the constituents of all kinds of ripe corn, and of many other vegetable substances. The farina or starch of the meal is more important in the arts ; but chemists recognise a high degree of impor- tance in the function fulfilled by gluten. Glycerine is a peculiar colourless, inodorous, sweetish liquid, obtained in various ways from many fats and oils. It was formerly thrown into the Thames as waste from Price's Candle Works, but is now usefully applied as a medicine, as an anti- septic, as a lubricant, as a solvent, and in various other ways. One formidable preparation of this sub- GNE 152 GOL stance is noticed under NITRO- GLYCERINE. Gneiss is a very hard stone, which the miner and quarryman have sometimes to blast or quarry away. It is midway in character between granite and mica schist. Goat's Hair. The Angora, Cashmere, and Syrian varieties of the goat yield beautiful hair, valuable in the arts, of which 4,000,000 Ibs. were imported in 1867. (See CASHMERE SHAWLS.) Gobelins Tapestry. Gobelins is the name of the celebrated tapes- try establishment belonging to the French Government. It does not cultivate any particular mode of interlacing the thread (on which subject see TAPESTRY), but aims rather to elevate the taste of the workers by copying high-class pictures. In doing this, not only is the general effect of the original picture faithfully rendered, but the intention and feeling of the artist are preserved in a degree really remarkable, when we consider that the process is purely a mechanical one. High-class specimens of Gobelins tapestry are more or less familiar to us. At the Great Exhi- bition in 1851 there was a copy of RafFaelle's fresco, in the Farnese Palace, of Psyche and the Genii ; and another of Horace Vernet's picture of the Massacre of the Mamelukes by Ali Pasha. At the International Exhibition ' of 1862 the display of Gobelins tapestry was equally fine. When the French had an opportunity of exhibiting in their own capital, their pro- ductions were of course more lavishly brought out. This was the case in 1855, and still more notably in 1867, when the vast Exhibition building contained, amidst its other treasures, a very fine selection of high-class tapestry-work from the Gobelins establishment. Gold, the most generally admired of all metals, is also one of the few found native in a pure state, as well as in many forms of combination. When free from all adulteration, it has a beautiful yellow colour, and is nineteen to twenty times as heavy as water. It fuses at about 2016 Fahr., and is volatile at a very high tempera ture. It is the most imperishable, the most easily worked, and the most malleable of all metals, permitting it to be used as a wonderfully thin covering to other metals and to various substances. When preci pitated, it forms a brown powder, which may be burnished down to the appearance of rich malleable gold. It combines with other metals to form alloys ; but there are few of these used in the arts except the alloy of gold with silver and coppet to form sterling gold and jewellers' gold. The colour of jewellers' gold may be varied by the application of certain chemicals, which partially dissolve away the silver and copper. Iron is sometimes contained in jewellers' gold, to enable them to produce various tints. Some of the compounds of gold have long been used for special purposes. With chlorine it forms chloride of gold, used as a liquid to give a thin coat- ing to fine cutlery and other articles of polished steel ; it is also useful for gilding porcelain. A complex union of gold and chloride of tin produces the pigment known as the purple of Cassius, used with such beautiful effect in enamel and porcelain painting, and in colouring Bohemian glass. Gold Deposits. Gold is found in various parts of the world, and in a variety of forms. A little has been found in all the four sec- tions of the United Kingdom, but seldom in sufficient quantity to make it worth extracting : the largest known specimen was a nugget of 22 ozs., found in Wicklow county. The sands of the rivers in Hungary and Transylvania contain much gold ; those of Spain, Switzerland, and GOL 153 GOL Germany a little. Russia in Asia contains a richer supply than any part of Europe, both in the Ural Mountains and further east in the heart of Siberia ; it occurs dissemi- nated with quartz in rocky veins, and also in gravel and river mud : on one occasion a piece of nearly pure gold, -weighing 8olbs., was met with in the Ural. Most other parts of Asia, such as China, India, and Asia Minor, contain a little of the precious metal. Africa has many tracts of sand more or less rich in gold in the valleys of the rivers of Gambia, Senegal, and Niger, along the Gold Coast of the West, and on the Mozambique coast of the East. America has been known for its gold since a period long anterior to the arrival of any Europeans on that continent in the Apalachian chain of mountains, from Virginia to Alabama ; in Canada and Nova Scotia; in Columbia, Brazil, Bolivia, Ecuador, Mexico, and Peru. But most of all is America rich in gold in the district lying between the Rocky Mountains and the North Pa- cific, partly in California and partly in British Columbia. There it is found in quartz rock, in nuggets in the gravel, and in fine sand and mud. Australia is a great rival of America in this precious deposit. Gold was first discovered in the colony of New South Wales in 1851, since which year enormous quantities have been found there and in Victoria, especially near Ophir diggings, Ballarat, and Bu- ninyong : here it is in the three forms of gold dust in streams, nug- gets in beds of clay, and as veins in quartz rock. Sumatra, and more recently New Zealand, have been added to the list of gold regions ; and it is the opinion of geologists ' the list is likely to be much iurtiier extended. They have a right to be heard, for Sir R. Murchison predicted the finding of gold in New South Wales Ion? before it was actually found, by comparing the geology of the Blue Mountains in New South Wales with that of the Ural. The gold mines of Cali- fornia yielded, between 1848 and 1866, the enormous amount of 36,945,000 ozs. of gold, worth 2*147,000,000. Those of Victoria, in Australia, between 1851 and 1867, yielded 3 3, 900,000 ozs., worth ^136,000,000. These are exclusive of the figures for British Columbia and New South Wales. G-old Mining:. Where gold oc- curs in hard underground rocks, it requires a regular pi ocess of mining. In some places, 20 or 30 feet below the surface, there is a layer of clay and soft greasy slate impregnated with lumps of gold a shaft is dug down to the proper depth, the earth is brought up in baskets and buckets, the visible bits of gold are picked out with a knife, and the earth is then washed to obtain the finer par- ticles. One man, with nothing but an old frying-pan and a bit of stick, picked out ^"5 worth of gold from such earth in half a day. In special instances there have been pieces found weighing not only ounces, pounds, tens of pounds, but even so much as 2,166 ozs., worth ^8, 3 76: this was the magnificent " Welcome" nugget, found at Ballarat in 1858. In various parts of Europe and Asia gold has been found in the same way, embedded in layers of sand, gravel, and clay, at depths varying from i o to 50 feet below the surface, but nearly always on the margin of rivers. The Veal operations of mining are called for in cases where the gold has not liberated itself from the parent rook, which may be any one of many kinds of slate, quartz, and pyrites. Some of the mines in these rocks have been dug to a depth of loo to 150 feet ; and it is certain in such cases that the me- tallic gold bears but a very small proportion to the stone. Generally speaking, when gold has once been GOL 154 GOL found in a mine, the richness of the quartz will not increase as greater depths are reached ; and therefore there is no incentive to very deep mining. All the quartz, when brought up to the surface, requires crushing as a preparative to further operations ; and the specimens so crushed vary excessively in richness. In Merionethshire in Wales, where there have lately been forty or fifty gold mines worked, the yield has varied from 3 dwts. to 400 ozs. per ton of quartz crushed. In one year no less than 350,000 tons of quartz were mined and crushed in Victoria, yielding an average of 17 dwts. of gold per ton. The crushing, grind- ing, and pounding of the quartz are effected by some such means as those noticed under ORE DRESS- ING. Gold "Washing. The separation of gold from the stony and earthy impurities is managed in different ways in different districts, depend- ing in part on the richness of the deposit, (i.) In Chili and Peru the ore is shaken about and washed in a shallow iron pan held in the hand until the heavier particles fall to the bottom. (2.) In Hungary the particles are allowed to separate into sizes by falling down an in- clined table. (3.) In Brazil the ore is thrown by bucketsful into a kind of cradle sieve, which is rocked to and fro until an effective separation takes place, leaving in the sieve any pieces of gold large enough to de- serve the name of nuggets. (4.) In Siberia a kind of mill is used for pulverising auriferous sands : there are mullers or pestles of hard wood which crush the particles, and a current of water which carries the sfuff down from one such mill to another, thereby enabling the pro- cess to be repeated time after time. Various kinds of sieve, rocker, and sluice are employed in Australia. All the small particles of gold in sand and gravel seem to have been washed out of disintegrated rocks ; they are therefore more highly valued by the miner than gold quartz, seeing that a great part of his labour has already been done for him by natural agencies. It was in the sands of streams that glittering particles first attracted attention to the gold deposits of California and Australia. To effect the absolute isolation of the precious metal from all impurities, the fragments, ground to a powder, are mixed with a cer- tain quantity of quicksilver ; the mercury and the gold combine to form an amalgam apart from all other substances ; and, by a further process, the mercury is recovered for future use, leaving the gold in a pure state. Of course, where the pure gold itself is found in nuggets or grains, this amalgamating process is not necessary. Goldbeaters' Skin is one among many forms of thin membrane use- ful in the arts. It is made from the intestine of the ox, which is scraped to remove the fatty matter ; then turned inside out in order to be scraped and washed on both sur- faces ; then left to ferment to loosen the mucous and peritoneal mem- branes ; then scraped against a blunt edge to remove these membranes. After various scrapings and cleans- ings in alkaline solutions, two membranes are placed together, with the mucous surfaces in con- tact ; and each pair, after various processes of steeping, beating, press- ing, and drying, in which solutions of alum and white of egg are em- ployed, form one sheet or leaf of gold- beaters' skin a thin but tough and very peculiar substance. It is used for medical and various other pur- poses, but chiefly by the goldbeater (in the way described in the next article). A mould of goldbeaters' skin contains 800 to 1,200 leaves, about 5j inches square. It is said that 500 oxen yield only enough of this peculiar membrane to make GOL '55 GOL one mould of 800 leaves. The making of this substance is a dirty and repulsive trade, but the product in the form of a mould of leaves possesses a high money value 8tOjia Gold Beating 1 furnishes a beauti- ful proof of the malleability of gold, or the power of being beaten out into thin leaves. The gold is al- loyed with silver, copper, or both, to produce various tints, and is first made into small ingots i^inch by |- inch, and 1% inch thick. The ingot is passed repeatedly through two polished steel rollers, until it becomes a long ribbon only -gfa inch thick. The ribbon being cut into inch-square pieces, 150 of these are interleaved with thick paper, and enclosed in a parchment case called a kutch. The kutch is subjected to a long-continued series of blows, administered with a i6-lb. hammer, and to all parts of both surfaces equally. When each gold piece has been stretched out by this beat- ing to 4 inches square, the kutch is opened, the pieces are cut into four of 2 inches square each, and these are interleaved in a book of gold- beaters' skin called a shoder, the r 50 pieces being now 600. Another beating with a g-lb. hammer spreads out these as before, and another cutting augments the number from 600 to 2,400. These are separated into three packets of 800 each, and each of these packets is again beaten in a book of goldbeaters' skin called a mould ; this beating, lasting four hours, is with a 7-lb. hammer. The leaves of gold, now reduced to the proper thickness, are cut with smooth wooden knives into 3^ inch squares ; twenty-five of these leaves are in- terleaved in a book, the paper of which has been rubbed over with red chalk to prevent adhesion ; and four such books, containing 100 leaves of gold, are worth about 5-y. According to the tint, the gold ob- tains the technical names of fine, red, pale red, deep orange, lemon,. pale, party, -white, &c. Leaf-gold is the thinnest substance produced in the mechanical arts, being only f an inch m thickness, a single grain covering 56 square inches. A medium kind is made of 42 parts pure gold, 12 silver, and 6 copper. Silver leaf and cop- per leaf, and mixtures of the two, can be beaten out, but not to such an excessive thinness as gold leaf. Dentists' gold is thicker than the ordinary leaf-gold. Gold-lace Manufacture. The term gold lace is a misnomer ; the substance is gilt lace. A rod of sil- ver is thinly coated with gold, and then rolled and drawn until it be- comes an exquisitely fine flattish wire. By this time the gold has, indeed, become so inconceivably thin that I oz. covers 100 miles of wire; and yet it coats the silver in every part. Yellow silk thread, spun on purpose, has this silver- gilt wire twisted round it by a small machine; and then gold-lace braidings, &c., are woven with the complex thread thus prepared. Eng- land receives much of her gold lace from Belgium ; but France takes the lead in this manufacture. Gold-weighing Machine. Mr. Cotton, when Governor of the Bank of England, invented one of the most delicate automatic machines ever seen for weighing sovereigns. The machine detected the smallest differences, and separated the sove- reigns into two groups, light weight and good weight. Mr. Pilcher, of the Royal Mint, has improved upon the machine, by enabling it to se- parate into three groups, for light, medium, and heavy. At the Mint it is employed to weigh, not sove- reigns, but the blanks which are to become sovereigns. The blanks are piled in a heap, and descend an in- clined shoot or tube. They pass through or between wonderfully delicate pieces of mechanism, until GON GRA they descend, one by one, upon a sort of balance or scale-pan ; if just the proper weight, they tip off and fall into a particular box ; if overweight, into a second ; if under- weight, into a third. Human fingers have nothing to do with it after the machine has been fed with a pile of blanks : steam or atmospheric power effects all the rest. G-ongr, a kind of tambourine used in the East as a bell, is made of one variety of bell metal, consisting of 4 parts copper to I tin. When freely suspended, and struck with a wooden hammer, it gives forth a very loud and deep tone. Graduation, or the placing of measuring" marks on an instrument of any kind, might seem to be a very easy process ; whereas it often requires the highest refinement of mechanical art. A carpenter's rule, with the inches divided into eighths, may be taken as a type of such divid- ing or graduating as can be easily effected to the requisite degree of accuracy. A mural quadrant for an observatory, in which the ity^th part of an inch is regarded as a serious quantity, is the type of a wholly different kind, in which eyesight and mechanical delicacy are taxed to the utmost. The substances ope- rated upon are box, larch, and one or two other kinds of wood, and ivory, brass, platinum, silver, gold, &c. In a few cases the graduation marks are painted on the surface ; but more usually they are engraved or incised. The more delicate gradua- tions are upon circles or portions of circles for quadrants, sextants, theo- dolites, transit instruments, equa- torials, mural circles, rather than upon straight-line measurers. The gracluator or divider is provided with pattern plates, rings, straight- edges, and other guides of similar kind. There are machines called dividing engines employed in the more delicate examples of gradua- tion, on which the utmost skill of such men as Ramsden, Troughton, Simms, and Ross has been dis- played. Special graduations, of great fame, are Froment's electro- divided lines, 25,000 to an inch ; Nobert's lines on glass, 57,000 to an inch ; and Whitworth's matchless micrometer, measuring a space of one millionth of an inch ! The last named, however, measures by screw threads, not by graduation. Granite, regarded as a building stone, is not so much used in this country as its abundance would jus- tify. The great difficulty and cost of working it render it an expensive material where labour is paid for at a high rate. The bluish-white Aberdeen granite is the best in our island for large constructive works fine-grained, little affected by wea- ther, and taking a good polish. This granite, rough from the quarry, commands from 4-r. to IOJ. per cubic foot, the largest blocks being the dearest per foot. Dartmoor granite is almost equally in esteem with Aberdeen. The granite of Peterhead has a reddish tint. The difference between the two is mainly this the grey has more mica than the red, while the red has more felspar and quartz than the grey. The working of granite for orna- mental purposes is very difficult, owing to the hardness and crystal- line structure of the substance.' The blocks are sawn by powerful steam- worked saws, wetted by quart/ sand and water ; and it is said to require a whole day to cut a groove two- thirds of an inch deep in a large block. The manual labour upon the granite is mostly applied by means of hand-picks, about 4lbs. weight, with short handles, and chisels having a very peculiar tem- per, struck by iron mallets. It is extremely slow work, requiring much tact to act upon the stone at all. Flat surfaces are ground and polished by rubbing one block or slab upon another, with siliceous sand GRA 157 GRE and emery bet ween them. Cylindrical and other curved surfaces are ground and polished by causing them to ro- tate rapidly by steam power, and applying properly-curved iron tools touched with sand and emeiy. The actual curvatures themselves are produced almost wholly by the hand-pick and the chisel. One of the finest English works in granite is the statue of the Duke of Gordon at Aberdeen ; but the most usual applications of the stone are to the making of bridges, piers, quays, and other ornamental works, slabs for steps and pavements, together with chimney-pieces, table-tops, seats, pedestals, columns, vases, and tombstones. Grape Shot. Large leaden bul- lets or small iron balls, from 6 ozs. to 4 Ibs. weight, according to the ca- libre, are built up into a kind of cy- linder ; when fired from a gun, the missile flies to pieces, and the bullets and balls work great destruction. Graphite. (See BLACK-LEAD.) Graphotype is one among many attempts to expedite the engraving of wood blocks, or rather to find a substitute for engraving. It was commenced by Mr. Hitchcock in 1865, and advanced further by Mr. Fitzcook. A zinc plate, covered with fine French chalk, is heavily pressed under a steel plate, to give a smooth glossy surface. When sized this surface has the picture drawn on it with a hair-pencil dipped in an ink or paint of lamp-black and glue. When dry, the surface is rubbed with a fitch brush and a velvet pad, the chalk between the ink lines is rubbed down by this friction, while the ink lines 'them- selves remain intact. Immersion in a solution of silica of soda or liquid glass then hardens the chalk into a kind of marble. The raised lines permit the plate to be printed from by a common press, in the same way as an engraved wood block. Grapnel is a kind of small an- chor, with a number of claws stick- ing out in various directions ; it is also much used in naval actions, to grapple the enemy's rigging, &c. The most remarkable use of grap- nels hitherto known has been in catching hold of the Atlantic cables at a vast depth beneath the ocean. Grapnels are often called grappling- irons. Grass Cloth is a misnomer. There is a very delicate kind of mus- lin or cambric made in the East, and known under this name, but of a fibre much finer than any grass can yield. Grate. (See FiRE-PLACE; STOVE.) Gravel is a collective name for pebbles, small pieces of rock that have become rounded by attrition. They may be as small as a pea or as large as an egg, and may comprise many different kinds of stone. Gravel is much used in making con- crete and artificial stone. Grease, in general acceptation, is something between an oil and a fat ; but in truth nearly all kinds of oil and fat may be used as grease, and those usually selected are such as are too dirty for candle-making or soap-making. Railway en- gineers, however, are very particu- lar about the grease used for their lo- comotives and carriages, of which vast quantities are needed : tallow, palm oil, sperm oil, alkali, and water are used in certain proportions, to make hard grease for summer and soft for winter. Green. The green pigments and dyes used in the arts are very varied, derived in part from the vegetable kingdom, but mostly from the mine- ral. Scheele's green, Brunswick green, chrome green, emerald green, sap green, and Schweinfurth green are the principal kinds. It is more usual, however, to mix some kind of yellow with some kind of blue, by which an almost infinite variety of green tints can be produced. GRE 158 GUN Green Vitriol is now called by chemists sulphate of iron. Grenade. This missile is not used so much as formerly. It is a hollow ball filled with combus- tibles, and ignited by a time-fuse. When thrown from the hand, it bursts, and the fragments work much mischief among the enemy. Grinding- is the most unhealthy of all trades in steel manufactures, owing to the tendency of metallic and stony particles to enter the lungs. A grinding mill or establishment at Sheffield is usually called a wheel ; the distinct rooms in it are called hulls ; and the distinct grindstone in each hull troughs. One system of steam power works all the grind- stones ; and the grinder pays a rent for the space and the power supplied to him. The grindstones are from 6 to 24 inches in diameter, turning on square iron horizontal spindles. They are made of various kinds of sandstone grit, procured mostly from English quarries, and each kind suited for grinding some particular sort of steel work. In most in- stances the grinder sits astride a plank called a horse, and has facili- ties for applying water to the grind- stone while using it. Some steel goods require large grindstones, some small (razors the smallest) ; some need wet grinding, some dry. Most fine cutlery, as well as forks and needles, require dry grinding ; and this renders these trades par- ticularly hurtful, on account of the dry steel dust floating about, a fork- grinder seldom surviving his thirtieth year. Small grindstones give con- cave surfaces, which in their turn give sharper edges. Large stones grind more rapidly than small, and dry more rapidly than wet ; the grinder knows by experience which is best. Other kinds of grinding are very numerous such as grind- ing glass lenses, glass plates, tele- scopic specula or reflectors, dia- monds and other gems, plane sur- faces of cast or rolled iron, gun barrels, steel pens, needles ; as also the crushing of substances into small particles, such as corn, chocolate, drugs, colours, &c. Both of these classes of grinding are noticed under numerous headings relating to the substances operated upon. Grindstones, used for the pur- poses just adverted to, are mostly flat circular discs, with the grinding surface either on the flat sides or on the circular edge. They are generally made of some kind of sandstone or millstone grit, of which Newcastle, Bilston, Devonshire, Yorkshire, Congleton, Sheffield, and Wickersley are noted varieties. (See also MILLSTONES.) Groats, or Grits, are oat grains with the outer skin rubbed oft". Those made at Emden, in Germany, are crushed into smaller bits, and are othenvise of good quality. Guillotine, a dread instrument of punishment, used with terrible effect during the French Revolu- tion, consists of a vertical frame- work, with a pulley at the top ; from this pulley is suspended a sharp iron blade or axe, guided by side grooves in the framework. The neck of the unhappy victim being placed on a block, a rope passing over the pulley is loosened, the blade falls, and decapitation ensues. Gum. In most instances gums exude from trees. The chief kinds used in the arts are gum ardbic, Senegal, and tragacanth. Some are called^wz resins, such as asafoetida, benzoin, storax, galbanum, ammo- niacum, myrrh, and scammony. See under various headings. Gun. This term is very indefinite. A sportsman's fowling-piece is his gun, and the most powerful pieces of artillery are also called guns. A few details on matters of construc- tion and dimensions will be found under ARMSTRONG GUN ; CAN- NON FOUNDING; MORTAR, MOR- TAR VESSEL ; SMALL ARMS, &c. GUN 159 GUN Gun Carriage. The carriages on which large ordnance are supported and moved about are necessarily of enormous strength, whether made chiefly of wood or of iron. They are provided with means for tilting up the gun at various angles, to give the required direction of fire; and with bearings and backings fitted to encounter the recoil of the gun, which invariably takes place just when the shot leaves the muzzle. This recoil, which has always hitherto been a source of trouble to the artillerist, has lately been brought into requisi- tion in a most admirable manner by Colonel Moncrieff. To understand the importance of this new invention, it may be well to note that there are two principal modes of firing shot and shell from land defences through embrasures or ports, and en barbette. In the former, a square hole is left in the masonry or earth- work for each gun, the gunners being as much as possible protected from the fire of the enemy. In the other method, firing en barbette, the gun is so lifted up as to fire right over the crest or parapet of the wall, without the need of any ports or embrasures. The advantage of this second plan is, that the gun can sweep round at any angle, to aim at the enemy ; the disadvantage is that the gunners and the gun itself are terribly exposed to the fire of the enemy. Now Colonel MoncriefPs plan consists in retaining the ad- vantage while avoiding the dis- advantage. When engaged outside Sebastopol during the Crimean war, he conceived the happy idea that the gun, while being fired enbarbette, might utilise its own recoil, and descend to a point where the gunners might reload without being exposed to the enemy. Having laboured in this direction during many years, he has at length devised a gun car- riage of very remarakble character. When pointing over the parapet en barbette, the gun rests on two triangular brackets belonging to the carriage, with two elevators in front, two rollers in the rear, and a counterbalance weight. A pecu- liar circular movement in the ele- vators, and a straight-line movement in the common centre of gravity of the gun and the elevators, are brought into requisition in such a way that the gun lowers its"elf by the very act of recoil, descending altogether below the parapet, out of sight of the enemy. The gunners then clean out and reload the gun. By a very slight movement of a part of the apparatus, the counterweight descends, and causes the gun to ascend just into its original position. By other ingenious contrivances the gun can be swung round to any azimuth, elevated to any altitude, aimed accurately at the enemy, and fired, without the gunners being for one moment exposed to the view of the enemy. In September, 1868, these remarkable qualities were fully tested during a series of experi- ments at Shoeburyness. The results are regarded as of so important a character by the military and naval authorities as to suggest a hope that this mode of working heavy guns might possibly render un- necessary the armour plating of granite forts, and the use of armour turrets for ships of war. G-un Cotton, as a substitute for gunpowder, has undergone a large amount of experiment and inquiry on the part of chemists ; but much still remains to be ascertained before the real degree of usefulness of the substance can be determined. In 1833 Braconnet discovered that a substance obtained by the action of nitric acid on starch, sawdust, and cotton wool is white and pulverulent, and very inflammable ; he called it xyloidine. In 1838 Pelouze dis- covered that paper treated with the same acid produces a peculiar kind of combustible parchment, appli- cable to artillery purposes and to GUN 1 60 GUN fireworks ; this substance obtained the name oinitramidine. In 1847, Sclionbein patented a process which arose in some" degree out of these discoveries, viz., a mode of making cotton as explosive as gunpowder; this substance he named gun cotton. By his process cotton wool is soaked in a mixture of nitric and sulphuric acids, slightly pressed, washed to get rid of the surplus acid, dried, steeped in carbonate and nitrate of potash, and again dried. Other methods of making it have since been devised ; but the primary point is the steeping in acids, which greatly changes the chemical con- dition of the cotton without much changing its appearance. Gun cotton, compared with common cotton, is heavier, harsher, more electric, more soluble in ether. When dissolved in ether it forms collodion, so much used in photo- graphy. It explodes violently at 350 to 400 Fahr. much more rapidly, indeed, than gunpowder, having thrice the force. Hence the supposi- tion that gun cotton would be a valuable substitute for gunpowder as an explosive agent, for artillery purposes, sporting, blasting, and pyrotechny. A great drawback to the realisation of this hope is the danger attending the use of the sub- stance, due to the temperature at which it explodes, and the violence of the explosion. The making of it is very perilous, having led to several frightful calamities. Artillery- men, too, object to its suddenness of action ; for the explosive force expends itself before the ball or bullet is prepared to receive the full effect. This is quite consistent with the results of experiments on gun- powder, by which it is known that the powder may be too violent and sudden in its action for artillery purposes. Gun cotton has another defect : it absorbs humidity very rapidly, and cannot be used till re- dried. Baron Lenk, as military engi- neer in the Austrian service, has treated fully on the subject of gun cotton, showing the precautions necessary in making and using it, and the kind of services which it is fitted to render. Gun Felt. A substance under this name was patented by Mr. Reeves in 1868, consisting of cotton rags torn into fibres, and treated with certain chemicals. He claims for it properties inter- mediate between those of gun- powder and gun cotton. Q-un Lock is an apparatus for igniting the charge. It has advanced in improvement by several stages, (i.) In the earliest muskets a slow match was applied by hand to the powder in the touch-hole. (2.) In the match-lock the match was brought down by a trigger and lever upon the touch-hole. (3.) In the wheel-lock a rotating steel wheel, coming in contact with a piece of flint, struck sparks, which kindled the powder in the touch-hole. (4.) In the flint-lock the contact of flint and steel produced a spark in a more convenient way than in the wheel-lock. The flint-lock is used almost everywhere now, except by those nations which have advanced to (5), the percussion-lock, in which a hammer gives a smart blow to a small percussion-cap, explodes some composition contained in it (see PERCUSSION CAP), and kindles the powder through a small hole in the nipple on which the cap is placed. All the famous rifles of the present day Enfield, Snider, Pritchett, Henry, Westley Richards, Lancaster, Whitworth, Chassepot, Needle Gun, &c. have locks peculiar to them- selves. See further on this subject under SMALL ARMS. Gun Manufacture is one of the most important handicrafts at Birmingham, Liege, and certain other towns. It always refers to the making of muskets, fowling- pieces, and other small arms ; never GUN 161 GUN to large guns or cannon. The trade is much subdivided. Barrel forgers; barrel borers and filers ; lock and furniture forgers ; lock filers ; lock finishers ; furniture filers ; ribbers and breechers ; stackers ; screwers ; strippers and finishers , polishers and hardeners these and many others are distinct trades. It depends upon the magnitude of the gunmaker's operations how many of these trades he carries on himself; but it is matter of notoriety at Bir- mingham that a gun travels many miles through the streets of that town to have the several parts put together. The barrel-making is per- haps the most important of all ; for whether made by bending round a strip of iron to the form of a cylinder, or twisting a ribbon of iron as a coil round a mandril, or forming it by a kind of tube-drawing between rollers the finishing processes are of the utmost importance to the efficiency and safety of the weapon. According to a recent estimate, the gun manu- facturers of Birmingham employ 7,000 hands, those of London 2,000, besides 2,000 in the Government Small Arms Factory atEnfield. Con- cerning the mode in which machinery now comes to the aid of the gun- makers, see SMALL ARMS. Gunny Cloth; Gunny Bags. The Hindoos make vast quantities of coarse cloth with spun jute, and sell it at a low price, under the name of gunny. Being well suited for wrapping raw cotton, it is used extensively for that purpose. The native dealers sell it either made up into bags, or in pieces, each large enough for one bale. Besides pack- ing all the Indian cotton in these bags and cloths, as many as 6,000,000 yards have been exported to America in one year for a similar purpose. Gunpowder. Some composi- tion analogous to gunpowder seems to have been known to the Chinese two thousand years ago. The Arab traders to China heard of it, and in- troduced onevariety to the south-east of Europe, M'here it was known as Greek fire. During the middle ages, Albertus Magnus and Friar Bacon wrote on the deflagrating and deto- nating qualities of a mixture of sulphur, saltpetre, and charcoal ; and Berthold Schwartz, whom the Germans claim as the virtual in- ventor of real gunpowder, unques- tionably described it about the year 1300. So nearly to an agreement have the nations of Europe arrived as to the best proportion of ingre- dients for gunpowder, that none of them differ far from this formula : 75 saltpetre -f- 15 charcoal -f- 10 sul- phur by weight. Most foreign countries use a little more sulphur and a little less charcoal in their gunpowder than England. The pur- pose to which it is to be applied large guns, small arms, sporting, blasting, and pyrotechny affects somewhat the proportions of ingre- dients. The saltpetre or nitre em- ployed in gunpowder-making is not pure enough as imported. It requires to be purified by repeated processes of steeping, boiling, cool- ing, filtering, crystallising, and fus- ing, to get rid of extraneous matters which are mixed with it. The charcoal is made from alder, dog- wood, and white willow, charred in iron cylinders, and kept -as free as possible from anything beyond absolute carbon. The sulphur, procured mostly from Sicily, re- quires purifying by being kept in a melted state for several hours in vessels made of gun metal. The gunpowder manufacture is con- ducted as follows : Mixing. When the ingredients have been sepa- rately reduced to fine powder, they are ground in the incorporat- ing mill, under a large and heavy runner, which may be made either of stone or of cast-iron. A little water is added to the powder. The quantity barely exceeds 40 Ibs. at a time ; and the mixture is ground for GUN 162 GUT several hours, to insure thorough in- corporation. Pressing and Grain- ing. The mixture, a greyish sub- stance called mill-cake, is subjected to heavy hydraulic pressure, and brought to the state of thin, smooth press-cake. This cake, broken into pieces, and crushed by toothed roll- ers, is rubbed over sieves with blocks of lignum-vitae, which bring it to the state of small grains. The grain is made purposely of different sizes, to suit different modes of using. By a somewhat modified process what is called pellet pow- der is made for artillery use. Glazing. The gunpowder, in a cylinder or cask, is rotated thirty or forty times a minute, by which the grains rub against each other, wear down all angles and protuberances, and become smooth and polished. The powder absorbs less moisture, and bears shaking better, when well glazed. Drying. To dry the gun- powder at a temperature of about 150 Fahr., it used to be placed in a cast-iron oven, heated on the out- side by a fire ; but it is now more cus- tomary to expose the gnupowder openly in a drying-room heated to the required degree by steam- pipes. The great explosive power of gunpowder renders its manufac- ture a dangerous one. Every pre- caution is taken in gunpowder mills, and in magazines, to avoid the use of artificial lights, and to guard against the production of sparks from metal, &c. The great catas- trophe near Erith in October, 1864, when 100,000 Ibs. of powder ex- ploded, showed the necessity for pre- caution. At Purfleet Magazine no less than 5,000,000 Ibs. are stored. The explosion of gunpowder is an- other expression for the sudden ex- pansion of a solid into a gas that occupies nearly 2,000 times as much space. As the gas will find room for itself, it expels a ball from a cannon with enormous velocity, or a bullet from a gun or pistol, or bursts open rocks in a quarry or mine, or dislocates into a thousand fragments the sunken hull of a wrecked ship, or blows up any building in which it may have been incautiously stored. In pyrotechny, gunpowder is used in many modified forms, to produce brilliant colours and fiery trains, as well as loud reports. Gunpowder, Protected. As it is dangerous to convey gunpowder from place to place, except under great precautions, means have been devised for rendering it temporarily non-explosive. Mr. Gale has shown that if finely-powdered glass be mixed with it, the gunpowder will not explode, even if a light be held to it. The minute particles of glass form a protective shield to each grain. The practical difficulty is, that the mixture must undergo a dangerous process of sifting before it can be restored to usable form. Ghinter's Scale. Edmund Gun- ter, about 1620, invented a scale which goes by his name, to perform certain mathematical problems by mechanical means. It consists of marks, lines, and figures, having par- ticular meanings. Gunter's Chain, by the same inventor, is a surveying chain of TOO links, 66 feet long in all. It assists calculations in measuring land, because 10 square chains = 100,000 square links = I acre. Ghitta Percha is one of those numerous vegetable juices which have become so valuable in the arts. It belongs to the same class of sub- stances as india-rubber, being an exudation from the trunk of certain trees. The natives of Borneo, Malacca, and other places in the East, have long been acquainted with gutta percha, which they collect as a juice, and allow to harden into various useful forms. In 1842 Dr. Montgomerie, of Bengal, introduced the substance to the notice of Europeans; and there gradually arose a market for it, which the GUT . 163 GYP natives were quite willing to supply. The gutta-percha tree (Isonandra gutta) grows to a height of 60 or 70 feet, with a trunk 3 to 4 feet in diameter. The natives make in- cisions in the bark at certain seasons, and allow the sap to flow into bam- boos or cocoa-nut shells, or, more recklessly, they cut down the tree in toto, in order to obtain a larger supply at once. The sap is boiled, to drive off as much water as possible, and then allowed to solidify by cool- ing. When quite pure, the sub- stance is greyish white ; but it usually comes to market discoloured with impurities. It can always be made soft and plastic by plunging into boiling water ; and in that state it can be moulded by hand, or by dies or moulds, into almost any form, which it will retain when cold. It is strong enough to form water- pipes ; sonorous to a remarkable degree for speaking-tubes ; an almost unequalled insulator of elec- tricity ; an excellent material for architectural ornament; a useful stopper for decayed teeth. It is used for cords and bands of various kinds ; for waterproof sheets or films ; for a waterproof solution when applied to textile fabrics ; for waterproof shoe-soles. In short, every year adds so largely to the practical uses of gutta percha, that it would be scarcely possible to enumerate them all. As a coating for the copper wire embedded in submarine telegraphic cables it is invaluable, on account of its efficacy in preventing the escape of elec- tricity laterally into the sea. Gutta percha requires peculiar processes to work it up into useful forms. The lumps, as imported, are cut up into slices by revolving knives. The substance is then soaked in. hot water, to get rid of some of the im- purities ; torn asunder into frag- ments by the jagged teeth of a re- volving wheel ; softened into a paste by hot water; kneaded and rolled between heated cylinders. In this cleansed, homogeneous, and plastic state, it may be worked into any form rolled into slabs or sheets, drawn out into tubes or rods, pressed into moulds, melted into a cement or varnish, &c. In making the sheets and slabs the gutta percha is passed between steel rollers, placed a certain definite distance apart; knife-edges will cut the sheets into strips of any width. The material is brought into tube form by a sort of wire-drawing process. As the surface will readily take paint, gilding, japanning, and bur- nishing, gutta percha lends itself easily to various forms of decorative application. About 15,000 cwt. of this valuable substance was im- ported in 1867 ; but when the Atlantic cables were about to be made the imports were exceptionally larger. Gypsum, one of the forms of sulphate of lime, is found naturally diffused in other rocks, chiefly new red sandstone. It is earthy, and at the same time rather fibrous in cha< racter. Certain properties which it possesses render it valuable in the preparation of moulds and casts. When mixed with water to a pasty or fluid state, it constitutes Blaster of Paris ; and, solidifying very soon af- terwards, can be almost immediately removed from the model or pattern. For making fine plaster the gypsum is broken into small pieces, calcined in an oven, ground between stones, and sifted to a fine powder : consi- derable tact is required in determin- ing the quantity of water necessary to be added to this powder, and the mode of adding it. To prevent the plaster cast from adhering to the model or mould which gives it form, the latter is first brushed over with oil or with white of egg. Moulds are often made in plaster of Paris, whe- ther the casts are to be of that sub- stance or of metal, such as stereo- type ; and casts are often made of GYP [64 HAI it where the moulds are of plaster, sulphur, or wax. Fine gypsum is also used as an ingredient in porcelain and best earthenware. The coarser specimens are kiln-burnt, and mixed with water into builders' cement for walls, floors, &c. Some of the harder kinds of gypsum are noticed under ALABASTER. Gypsum Cement. Gypsum sup- plies many useful kinds of cement. The prepared plaster of Paris, in fine powder, is mixed with alum, borax, or sulphate of potash, with a due proportion of water. The mixture, when dried, is baked at a dull red heat, reduced to powder, and sifted. According to the mode of mixing, and the addition of one or two other substances, are pro- duced Keene's cement, Martin's cement, Parian cement, stucco, and many other kinds. For the harder water - resisting compositions see CEMENT and HYDRAULIC CE- MENT. Haffcing-; Handling-. The ma- nufacture of hafts or handles for cutlery is a vast branch of industry at Sheffield, and to some extent at Birmingham, employing large num- bers of men, and necessitating the use of a singularly wide range of substances. Soft wood, hard wood, ebony, lignum-vitae, vulcanised in- dia-rubber, ivory, bone, hoof, horn, pearl, shell, tortoiseshell, iron, brass, gold, silver all are employed, and many other substances besides, either singly or in combination. To bring these substances into shape, almost every mechanical process known in the arts is employed sawing, planing, turning, carving, stamping, forging, casting, emboss- ing, inlaying, plating, electro-plat- ing, grinding, polishing, engraving, &c., according to the value, form, and size of each handle. Some han- dles are made by riveting flat pieces of bone, &c., upon a flat iron con- tinuation of the blade ; some by the through fang, an iron prong pro- jecting from the blade, fitted into a hole drilled right through the han- dle, and riveted at the end ; some by a shorter prong fixed into a snorter hole by resin solder; and some by weighting the interior of the handle with a little lead, to give the balance action to the blade. See further under BONE MANUFAC- H. , TURES ; CUTLERY MANUFAC- TURE ; HORN MANUFACTURES ; IVORY; MOTHER-OF PEARL; TOR- TOISESHELL, &c. Hair Manufactures. It is not always easy to define the difference between hair, bristle, wool, and fur; but the two kinds of hair most used in manufacture, horse hair and hu- man hair, may be taken as types of a class. Horsehair. The higher the feeding of the animal, the better the hair; hence the superiority of English horsehair to that obtained on the Continent. To prepare it for manufacturers, horsehair is classi- fied into best, seconds, black, grey, soft, hard, curling, spinning,, weav- ing, Sec. To prepare the curled hair for stuffing cushions, &c., short horsehair is carded between teeth or combs, tipped or beaten in a heap with a cane, curled into a kind of large rope, steeped in cold water, heated in an oven, opened by partial uncurling in an opposite di- rection, and towzed or picked into curling pieces, which acquire a re- markable springy quality. Short white hair is used for brushes. Hair of medium length is spun into clothes-lines, and woven into filter- ing bags, &c. The long hair, by processes of heckling, carding, &c., is woven up into horsehair cloth, for sofa coverings and so forth, HAI 165 which has a black flaxen warp with a horsehair weft, each weft thread consisting of a single hair. Accord- ing to the length of the hairs, so can this cloth be made of widths varying from 14 to 40 inches. Long white hairs are used for violin bows and fishing-lines. At some of the Industrial Exhibitions there have been displayed, from Russia, bowls, dishes, and plates made of hare and rabbit hair, felted into a tough layer, and varnished ; they had something the appearance of papier-mache. These, however, were examples ra- ther of fur work than of hair work. Human hair is mostly used over again as an imitation of other hu- man hair, in wigs, scalps, curls, chignons, beards, moustaches, &c. The value of hair for these purposes changes with the fashion, which is subject to violent fluctuations ; the price has been known to range from 4>r. to as much as ^4 per lb., especially when golden tresses were in favour, seeing that golden hair is comparatively a rarity. There are regular hair harvests in France, Italy, and Germany ; young women cut off their tresses, and sell them to itine- rant dealers ; merchants then buy the hair, dress it to a certain degree, and sell it to wig-makers. The making of wigs, perukes, beards, whiskers, moustaches, eyebrows, fronts, chignons, &c., constitutes a trade in itself, in which many inge- nious processes are involved. Be- longing to what may be called the chemistry of the trade is the prepa- ration of hair dyes, hair washes, hair pomades, and hair powders. How far the artist succeeds in in- creasing the beauty of human hair by these additions is a matter of fashion and individual taste ; but the amount of trade done in this way is very large. The making of hair-pencils is briefly noticed under BRUSH FLAKING. For various pur- poses in the arts, the hair of the camel, fitch, sable, hog, cow, badger, HAR goat, dog, and other animals is used. Ham Curing:. (See BACON; HAM.) Hammer. The ordinary ham- mer is so simple an implement that little more need be said of it than that hammer-making constitutes a large branch of trade in the Bir- mingham and Wolverhampton dis- trict. According to the length of the hammer, the shape of the two faces, the length of the handle, the angle at which the handle is adjusted to the hammer, the weight, and many other circumstances, hammers become applicable to a great variety of handicraft trades, and thus there are file-makers', sledge, riveting, lift, raising, planishing, goldbeat- ing, hacking, veneering, and many other varieties of hammer. The helve or shingling hammer is noticedunder IRON REFINING AND PUDDLING ; the ttltkammerunder STEEL MANTJ FACTURE. (See also FORGE HAM- MER ; STEAM HAMMER.) Hardness. This, as one of the qualities of solid substances, has been incidentally adverted to under GEMS AND PRECIOUS STONES. If diamond be placed at one end of the list, and opal or chrysolite at the other, then all the remaining kinds of precious stone occupy interme- diate positions. Tables have been prepared of the relative hardness of different kinds of metal, stone, wood, earth, &c. ; but there has not yet been obtained any very reliable standard of comparison. Hard-ware. This term is rather absurdly confined to one class of articles which, though certainly hard, are by no means the only kind that deserve the name. Hardware com- prises, so far as it is a commercial term, all the commoner useful arti- cles of iron made in Birmingham and South Staffordshire, as well as some of those in copper .and brass. It is not easy to name the limit to which this trade extends owing to the multiplicity of articles to HAR 166 HAR which the name of hardware is given ; but the Board of Trade tables classify them in the following way. Hardware and cutlery are said to com- prise : (l.) Knives, forks, scissors, shears, surgical and anatomical in- struments, and other articles of re- gular cutlery, of which we exported 2"48,ooo worth in 1867. (2.) Anvils, vices, saws, files, edge-tools, cranks, slide-bars, and tools or implements of industry other than agricultural, not wholly composed of iron or steel; exports, ,490,000. (3.) Manu- factures of German silver, pewter, Britannia metal, papier-mache, lamps, chandeliers, candelabra, and hardware not specifically described ; exports, ,3,000,000. The absurdity of such a grouping under " Hard- ware and Cutler)' " is manifest. Harmonica. (See MUSICAL GLASSES.) Harmonium. This may be taken as the type of a large number of musical instruments, the construc- tion of which deserves a little notice. What is called a free reed consists of a small plate of brass, with an oblong cavity in it, and a flexible tongue of brass almost exactly the size and shape of the cavity. Being fixed or pivoted at one end, the rest of the tongue will easily vibrate to and fro in the cavity ; and, in doing so, it will emit a musical note, the pitch of which depends on the dimensions and elasticity of the tongue. The Accordion is an appli- cation of this principle: there are as many cavities and tongues as there are notes, keys to determine which tongues shall be acted upon during the progress of a tune, and bellows to make the tongues vibrate. The Organ Accordion has a dif- ferent arrangement of keys and bel- lows, but similar tongues and cavities. The Flutina is an accordion with a peculiar quality of tone, due to the mode in which the air is allowed to pass out of the instrument after having acted upon the tongues. The Seraphine was the first instrument of this class which professed to be a substitute for the church organ. The ^Eolian is a very small instru- ment of the free-reed kind, with a mouth aperture instead of bellows. The Concertina is the most perfect of those varieties which are held in the hand, owing to many improve- ments in the keys and in the bellows action ; some of them have a range of 3-^ octaves, with all the semi- tones'. The Harmonium is the most perfect of Jthose varieties which are played like an organ, with a pedal to act on the bellows. The sound is produced, as in other instru- ments of its class, by elastic tongues vibrating in and out of cavities, in- stead of (as in the organ) pipes shaped and adjusted in various ways ; but in other respects a first-class harmo- nium very much resembles an organ in the main principles of its action. (See ORGAN, CHURCH.) As soon as the accordion, concertina, seraphine, and harmonium are understood, it will be easy to see the probable merits of a number of intermediate inventions, which have borne the names of yElophon, Melodium, Sym~ phonium, &c. There is no possi- bility of mistaking the sounds of any of these for pianoforte sounds, in which the vibrator is a wire struck by a hammer, instead of a tongue made to oscillate by wind; nor is it likely that any of them will equal the pianoforte in applicability to various kinds of music. Harness is the name for a large assemblage of strings, &c., in the weaver's loom. Harness Making-. (See SAD- DLERY.) Harp. As apiece of mechanism, the peculiarities of the harp depend chiefly on what is contained in the hollow diagonal front of the frame. The strings, which give all the notes of several octaves, are con- nected at the bottom end with cer- tain pedals, on which the foot of the HAR 167 HAT player is occasionally placed. The pedal, by suitable mechanism, places a check or stop at a particular part of the string, diminishing its vibrat- ing length, and causing it to yield a tone exactly half a note higher. In Erard's double-action harp every pedal has two stages of action ; by one it can be made to raise, and by the other to lower, the pitch of a string by exactly half a note. Very careful calculation, manufacture, and adjustment are required to secure these results. Viewed in a more ex- tensive light, there are three groups of harps, or modes of construction and action, (i.) Italian harp : this has two rows of wires or strings, separated by a double sounding- board. (2.) Double harp : this has a sounding-board and gut-strings, tuned to accidental flats and sharps by rather a clumsy contrivance. (3.) Pedal harp : this is the more perfect harp of the present day, above described, in which the foot, pressing upon a series of seven pedals, gives great power of musical expression. Harpsichord. (See PIANO- FORTE.) Harrow. When the harrow ceased to be a mere assemblage of spikes, fixed immovably in a frame which maintained a definite form, the power of working up the soil greatly increased. As now made, the iron tines are fixed to a frame which has either a certain series of movable joints, or such an ar- rangement of tines that each one scratches the ground in a line dis- tinct from those of the others. Two forms of it to produce special effects are the break and the chain harrow. Harrows have not yet been brought within the range of Steam Fann- ing (which see), the process of harrowing being too simple to ren- der such aid profitable. Hartshorn, properly so called, is a kind of spirit distilled from the antlers of the stag ; but it is now made directly of, or is rather substi- tuted by, some of the salts of am- monia. Hat Making:. The days of bea- ver hats seem to have nearly passed away, and with them the most in- teresting of the processes involved in the manufacture. Still there are some made ; and it will be useful to point out the chief differences be- tween felt, beaver, and silk hats. Felt Hats. Nearly all kinds of fur and wool have a felting property ; that is, the fibres will cling and in- terlock very tightly when twisted around or worked up among each other. This is owing to a series of minute serrations on the surface of the fibre ; and it is the same quality which renders possible the fulling of broadcloth. (See FELT, FELT- ING ; FULLING, FULLING MILLS ; WOOLLEN MANUFACTURE.) In a felt hat there is no fur, wool being the substance employed. The wool, laid out flat, is moistened with a hot liquor, and worked aoout in a peculiar way until it forms a kind of triangular fleece. A triangular piece of paper, less than half the size of the fleece, is laid upon it ; the edges of the fleece are folded over the paper so as to meet on the upper surface ; a further working joins the two edges ; and then the whole of the wool is worked up into a felt. The paper, which has prevented the two portions of felt from adhering, is now taken out ; there remains a co- nical felt cap, which is wrought into one of the many shapes of hat by being moistened and rubbed upon blocks. Beaver Hats. Beaver- skin is cleaned with soap and water, and the long hairs pulled out with the thumb and a short knife. The fur of short hairs is cut off by means of a sharp-edged instrument, and sorted into qualities. The fur is usually applied, not for making the whole hat, but as an outer layer on a foundation of rabbit's hair or lamb's wool. A conical cap of HAT 1 68 HAT (say) wool, about 14 inches by 15, is made in the way just described, and the napping, or outer layer of beaver fur, applied to it. In order to effect this, the fur is weighed ; bowed with a long string, plucked by the fingers, to separate and equally distribute the tangled mass of fibres ; pressed together into a layer of an oval form, to produce a kind of soft dry felt ; and then drawn over the conical cap or foundation of wool. Then begins the wet process. An open vessel called a battery is filled with soft water, to which sulphuric acid or stale beer is added, and kept hot by a fire underneath. There is a sloping edge at the top of the bat- tery, to serve as a work-bench. Here the two layers of hat are worked into one firm substance, wetted, and rubbed about with the hands in va- rious ways, until the fur fibres are thoroughly entangled among those of the wool. The cap is then pulled over a cylindrical block, and made to fit it by more wetting, rubbing, and pressing, with the lower por- tion to form a puckered commence- ment of a brim. The rudely-shaped hat is then dried, the nap carded up, sheared to a certain length, softened again with liquid, and again drawn over a block. At this stage the hat is dyed in a hot solu- tion of logwood, verdigris, and sul- phate of iron ; many dozens being dyed at once, in a kind of hollow frame which dips into the dye-vat. Then the hat goes through a variety of finishing processes to wash off the loose dye, drain and dry the hats, pick out coarse hairs by means of tweezers, strengthen the crown with a piece of scaleboard, bring the brim to a proper shape, block the whole hat to the desired form, smooth with warm and damp irons and brushes, line and leather the in- terior, trim and bind the exterior. Plate Hats. This name is given to an inferior kind of (so-called) bea- ver hat, in which the foundation is of wool instead of inferior fur, and the napping of inferior fur instead of beaver. Silk Hats, These are made of silk plush drawn over a very stiff but unfelted foundation. This foun- dation, according to the strength or the price intended, is made of calico, cambric, or other textile ma- terial, stiffened with shellac and va- rious other gums, and brought into shape by being worked over and around a block. The covering is a silk plush, woven with a kind of long velvet nap or pile on one sur- face ; it is made at Coventry and elsewhere, but the best kinds are imported from France. The cover- ing of the foundation with this plush is a work requiring much nicety to cut the plush so as not to make much waste ; to sew the pieces to- gether after being cut ; to give the foundation a coating of gum or ce- ment ; to fit the plush neatly on it ; to cause the two to adhere by mois- ture and the pressure of a hot iron ; to adjust the surplus plush carefully around the rim ; and to brush and smooth the surface in such a way that the seams in the plush shall not be visible. Pull-over Hats. These are a modern form, in which a thin beaver napping is applied as a covering to a body or foundation similar in character to that of a silk hat. Machine-made Bodies. The rabbit-fur bodies for silk hats are now often made in the follow- ing way : A copper case, full of per- forations, revolves on the top of a hollow shaft; a revolving fan pro- duces a downward current of air through the shaft; loose hairs of rabbit-fur, thrown upon the case, are sucked down close upon it by the draught of air acting through the perforations. The copper case can then be removed, leaving a conical cap of rabbit's fur, which can be felted in the usual way. Machines of a somewhat elaborate kind have been invented for making hats ; but most of the manufacture HAW 169 is still conducted on the hand-work system. After supplying home de- mand, we exported 270,000 dozen hats in 1867. For straw hats and bonnets see STRAW PLAIT MA- NUFACTURE. Hawser. (See ROPE MAKING.) In a ship the hawse-holes are the places where the cables and hawsers pass out to connect with the anchors. Haymaking- Machines. (See AGRICULTURAL MACHINES.) Hazel. The wood of the hazel- nut tree is useful for certain pro- cesses in the arts, such as making crates, hoops, hurdles ; and the charcoal prepared from it is well fitted for gunpowder and for black crayons. Heald, or Heddle. (See LOOM, HAND and MACHINE, and WEAV- ING.) The making of the vertical threads of healds, and the eyes in them through which the warp threads pass, is a special branch of trade in Lancashire and Yorkshire. Hearthstone. The soft white stone used for whitening door-steps, &c., is mostly quarried near God- stone, in Surrey. Heat. The vast range of scien- tific investigations concerning heat lies beyond the scope of this work ; but the practical results to which those investigations have led exert a direct influence on all such manu- facturing operations as smelting, forging, welding, melting, distilling, gas-making, &c. ; and upon the evolution of power in steam and hot- air engines. Temperature, dilata- tion, expansion, fusion, liquefaction, solution, vaporisation, conduction, radiation these and other terms serve to denote the several modes in which heat makes its effects manifest. Various examples of these heat-pro- ducing and heat-produced effects are given in the course of the work. Heat, Mechanical Equivalent of. An immense stride has been made in the philosophy of manufactures by the determination of the mecha- HEM nical equivalent of heat, chiefly through the patient , and masterly experiments of Dr. Joule. Heat, according to the modern view, is convertible into mechanical force or energy ; and a given quantity of the one is found to be equal to, or pro- ductive of, a given quantity of the other. This equation has been ascertained by measuring the friction of solids, liquids, and gases under various conditions, as productive of heat ; and, conversely, by measuring the mechanical work effected by a given amount of cooling. The unit of power is taken to mean the force which will lift I Ib. I foot high; this is called a foot-pound. The unit of heat employed is that quan- tity of heat which will raise I Ib. of water I Fahr. in temperature. Now it is found that about 772 of the former are equivalent to I of the latter ; that is, an amount of heat which would increase by I Fahr. the temperature of I Ib. of water would, under altered arrangements, lift a weight of 772 Ibs. I foot high. This ratio, which receives the name of Joule's equivalent, is becoming very important in settling the theory of the hot-air engine, steam-engine, and other machines worked through the instrumentality of heat. Heckle; Heckling:. (See FLAX PREPARATION ; HEMP MANUFAC- TURES.) Hemp bears a good deal of resemblance to flax as a material for spun and woven goods. It is the fibre obtained from the stem of a plant, separated from the woody matter, the bark, the seed, and every other part. The common hemp plant is the Cannabis sativa, which grows readily in many parts of the world ; but there are other kinds more or less analogous in character. Eng- land and Ireland could produce as good hemp as Russia and Poland ; but as our land is more profitably appropriated to other crops, most of the hemp used in British manu- HEM 170 HER r actures is imported. On a rich moist soil the fibre becomes coarse, but strong ; on a poor dry soil, weak, but fine; and thus different kinds can be obtained to suit the requirements of trade. Hemp Manufactures. The processes to which the hemp is subjected are as follows : Retting. When the plants are ripe they are pulled up ; the leaves, flowers, and roots are cut off; and the stalks are tied up in bundles. To dissolve the vegetable gluten which holds the fibres together, the stalks are retted. This is done in many ways : by burying them for a time in snow ; by exposing them to the slow action of damp and dewy air ; by steeping them in ponds of still water; by steeping in running streams ; or by steeping in water which falls from one level to another in a series of artificial tanks or ponds. The hot- water retting and steam-retting, described under FLAX DRESSING have not been much employed for hemp. Preparing. When the fibres have been softened, or rather the glutinous substance softened, by retting, the stalks are taken up, dried in the open air or in the sun, and sometimes in heated rooms. All the subsequent processes are so nearly like those for flax that it will suffice to refer to the article FLAX PREPARATION for a brief account of them so far, at least, as concerns the use of hemp in making textile fabrics ; such as canvas, bagging, sacking, sail-cloth, tarpaulin, tent- cloth, marquee-cloth, &c. Jute (which see) is becoming a for- midable rival to flax and hemp in various manufactures. Hemp, how- ever, maintains its superiority for many kinds of cordage. (See ROPE MAKING.) Ordinary Russian hemp presents various qualities in the market such as clean, half-clean, out-shot, and codilla. The last bears some such relation to good hemp as tow does to flax. Manilla hemp, and sunn, or Indian hemp, are two other kinds largely in use. About 900,000 cwt. of hemp was imported in 1867. When once the fibres have been cleaned and prepared, the SPINNING and WEAVING into SAIL-CLOTH, CANVAS, FLOOR- CLOTH, &c., and the twisting into ROPE, are conducted in the way de- scribed under those several headings. Henri Deux 'Ware. This name is given to a very select number of specimens of earthenware made in France during the reign of Henry II., something more than three cen- turies ago. They are supposed to have been made in Touraine, but nothing certain is known as to the artists' names. The material is a kind of fine pipe-clay, with a thin, transparent, greenish-yellow glaze upon it. Many of the specimens were evidently made by stamping patterns in the soft clay, and filling up the depressions with clays of other colours. The specimens known to exist at the present day (several at the South Kensington Museum) are only a few dozens in number, and the prices which they command from collectors are enormous. Herring Curing. Herrings are mostly caught on the British coast by what is called the drift-net. When brought on shore to a curing station, such as Yarmouth or Wick, they are sold by the cran of 45 gallons to the curers. In Scotland, most of the herrings, after being gutted, are packed in barrels with salt, and sold as pickled or salt herrings. At Yarmouth it is more customary, after salting, to smoke them, before packing in the casks, either into bloaters or into red her- rings, according to the mode of conducting the process. This her- ring trade is now one of great magnitude. Besides supplying the home demand, we exported in 1867 no less than 520,000 barrels of salt and cured herrings more than half to Prussia : - the value was set down HIC 171 HON at ,720,000. For 1864 the estimate was 730,000 barrels of herrings caught, and 640,000 barrels of them cured for home and export con- sumption. Hickory. The wood of the h ick- ory, a handsome North American tree, is subject to decay when exposed to alternations of wet and dry, and is not suitable for large works in car- pentry or engineering; but it is much used especially in the United States for carriage shafts, whip handles, wooden screws, and cask hoops. Hides and Skins. (See FUR, FURRIERY ; LEATHER ; PELTS, PELTRY.) As much as 100,000 cwt. of hides and skins was imported in 1867, chiefly from South America and India. Hinges are largely made in the Birmingham and Wblverhampton district, chiefly of iron and brass, but also of other metals. Various processes of rolling, forging, stamp- ing, and drilling are concerned in their manufacture. At the Paris Exhibition, 1867, a French inventor showed an ingenious hinge-making machine, capable of producing sixty door-hinges per minute. Narrow strips of sheet-brass are uncoiled from a roll ; the strips are punched out in the places where they are intended to interlock ; the wire which supplies the central pin is cut to a proper length; the two flat pieces are doubled round this pin ; the holes for the screws or nuts are pierce*d and countersunk; and finally, the finished hinge is thrown out of the machine. Hog. (See BACON, HAM; BRISTLES ; LARD; LEATHER.) The hog trade in the State of Ohio is so vast that most of the nations of Europe are supplied with salt pork from that source. Our own import often exceeds 500,000 barrels yearly, besides enormous quantities of bacon and ham. Cincinnati is the great centre of the slaughtering, salting, curing, and barreling establishments. Holland. (See FLAX; LINEN MANUFACTURES.) ' Hollands. (See GENEVA.) Hollow "Ware is a name given in the Birmingham and Wolver- hampton district to various kinds of culinary and other vessels made of iron. Some are made of wrougnt- iron by stamping ; some by riveting pieces together ; some by casting in moulds. These vessels may be left in the plain metallic state, or may be blackened on the outside by a kind of japan. The interior in cheap ware is left untouched, but the better kinds are either coated with tin, nearly in the same way as Tin Plate (which see), or with enamel (for which see ENAMELLED WARE). Holly. The wood of this tree, being white, hard, and fine-grained, is used for many ornamental purposes Hone, more frequently called whetstone, is always some piece of stone having a very hard and flinty, but at the same time smooth surface. Most parts of the world yield some stone or other of such a nature ; but the best is that of Turkey, known as Turkey hone. Most of them are moistened with oil when used, and are hence called oil-stones. It is mostly to sharpen the edges of cut- ting tools that hones are used, buf some of them are also employed in polishing copper plates. Cut-* lers, lapidaries, tool-makers, razor- sharpeners, jewellers, clock-makers, curriers all use hones specially adapted to their work. Honey. How the flower secretes honey, and the bee carries it away to its hive as a store of food, is for the naturalist to tell. When man comes to apply it to his use, he finds it to consist of sugar, wax, gum, and other matters. It is mostly used as a sweetening ingredient ; tobacco manufacturers employ a little ; and it is also fermented to make honey wine, or mead ; but the abundance and cheapness of sugar have kept the trade in honey down at a low ebb. HOO HOR Hoof. The hoofs of animals are largely employed in making the coarser kinds of handles, combs, and buttons ; and chemically they are found to be the cheapest sub- stance from which prussiate of potash can be obtained. Hooks and Eyes are among the products for which the needle- making town of Redditch is famous. Machines produce them very rapidly by drawing out wire from a coil, cutting it off', bending it into curves, bending the ends to form loops, and closing up the loops so as to form hooks or eyes, as the case may be. A far more delicate manufacture is that of Fish Hooks (which see). Hops, so valuable in making beer and ale, are the flowers of the hop plant. In strictness, the part used in brewing is the ripened cone or seed-pod of the female plant ; and it is a yellow aromatic dust at the base of the cone that is the real active agent. In autumn the plants are cut down to within a yard or so of the ground ; the flowers are picked off one by one, and thrown into bags ; and a sorting takes place according to quality and condition. The hop-kiln, in which the hops are then dried, is maintained at a certain temperature, somewhere between 80 and 90 Fahr. The hops are spread on the floor; and charcoal is used as fuel to produce the heat. So great is the quantity of moisture given off, that 5 Ibs. of fresh hops become only I Ib. when dry. The lighter and finer kinds are com- pressed into fine canvas sacks called pockets, about l cwt. in each, for the ale brewer; the darker and heavier kinds are put into sacks of coarser canvas, called bags, about 3 cwt. in each, for the porter brewer. The hops of Kent and Sussex are best for porter; those of Worcester for ale. More hops are needed in warm than in cold weather ; and more for beer or ale which is to be kept along time than for immediate [ drinking. The quantity used varies from | Ib. to i Ib. of hops to every bushel of malt. (See further under BREWING.) There are usually from 50,000 to 60,000 acres of hop gardens in England; but the pro- duce varies so excessively that it is scarcely possible to name an average : in some years it has fallen to 10,000,000 Ibs. ; in others it has risen to 80,000,000 Ibs. Our home supply not being sufficient, we im- ported 30,000,000 Ibs. of foreign hops in 1867. As the wholesale trade in hops is centred chiefly in the borough of Southwark, where most of the merchants and factors congregate, a Hop Exchange has been constructed, to facilitate the buying and selling. It was opened in September, 1868. It is situated at the junction of High Street and South- wark Street. The Exchange-room itself, 80 feet by 50, is supplemented by a subscription-room ; 120 offices for dealers in hops, malt, and seed ; 50 stands for the display of samples; and 4 or 5 acres of warehouse-room. Mondays, from 10 to I o'clock, and Thursdays, from 10 till 2, are the market days. Hornbeam. The wood of the hornbeam, being white, hard, tough, and strong, is much employed in turnery, joinery, and wheel-making ; it takes a good polish and a good stain, produces excellent charcoal, and an ash useful as potash. Horn Manufactures. The horns of various animals are manu- factured into a great variety of useful forms. Horn is a medium between bone and gelatine ; and it is not always easy to define the differ- ence, in structure and composition, between horns, tusks, antlers, hoofs, claws, nails, spines, and quills ; for they all contain albumen, gelatine, and phosphate of lime. The kinds of horn chiefly used for manufac- turing purposes are those of the ox, cow, bison, buffalo, chamois, and antelope. Some of the horns, HOR 173 HOR having a bony core in the interior, require to have this core removed ; this is effected by long steeping, which destroys a membrane between the two substances. The bony refuse, when burned, is useful for making the small cupels described under ASSAYING. The tips of the horns, being solid, are the best parts for buttons, cutlery handles, and the like. The hollow part, when softened by hot water or by a stove, is easily slit open with a knife, spread out flat, and pressed between iron plates or wooden boards into thin sheets ; such sheets are used in making lanterns, and a variety of other articles. By various processes of cutting, stamping, pressing, &c., the horn is made into combs, drink- ing cups, knife and fork handles, buttons, studs, &c. Indeed, the relation between horn and tortoise- shell is so close that most of the processes applied to the former are also applicable to the latter. (See TORTOISESHELL.) Horn easily takes colour throughout its entire sub- stance by boiling in coloured infusion. Imitative tortoiseshell (so called) is produced by treat- ing horn with a hot solution of dragon's blood, litharge, and pearl- ash, applied to those parts which are to be reddish brown, but not to those which are to be yellow. The parings, turnings, filings, and other fragments of horn, like those of tortoiseshell, can easily be softened and worked up into useful or orna- mental forms by pressure. Even if this be not done, nothing need be wasted, seeing that the manufactur- ing chemist can obtain useful sub- stances by decomposing the horn. The actual waste in manufactures is becoming less and less. Horn Silver was the name given by the alchemists to what is now called chloride of silver. Horology is the art of making time-measuring instruments. These instruments, and matters relative to them, are treated of under ALARUM ; CHRONOMETER; CLEPSYDRA; CLOCK; ELECTRIC CLOCK; ESCAPEMENT ; FUSEE ; PENDU- LUM ; SUN DIAL ; WATCH. The trade, so far as concerns England, is centred chiefly in Clerkenwell, Coventry, and Warrington ; and machinery is becoming more and more largely employed in the manu- facture. Swiss watches and clocks, and American clocks, which are made very cheaply, tend to keep down the prices of home-made goods. We imported 250,000 clocks and 120,000 watches in 1867. Horse Power. When James Watt was improving the steam- engine in many ways, he wanted some term that would denote the power produced some standard of comparison which would be generally intelligible. He adopted the phrase horse power, denoting the quantity of work which an average horse can perform. He accepted the result of certain experi- ments which seemed to show that a horse can raise 33,000 Ibs. to the height of I foot in I minute ; this he called i-horse power ; and he gave the name of 5O-horse-power engine to one which would do fifty times that amount of work, and so on. It has been found since his day, however, that by improved arrangements in every part, a cylin- der of a certain capacity will do more work than Watt had assigned to it. Hence a certain horse power nominal now only denotes a certain capacity of cylinder ; whereas the effective or real power denotes the actual working efficiency. Most engineers now believe that Watt's figures, 33,000 Ibs., are too high for a real horse power; but the foot- pound (see HEAT Mechanical Equivalent of) is still based upon them, for the sake of uniformity in statements and tabulations. In the great war-steamers and mail-steamers now built, the nominal and the real HOR HOT horSe power of the engines are both frequently named ; and it is observ- able that they diverge more and more from equality. Horse Shoes are mostly made in the Walsall district by forging, with the aid of certain pattern dies to give the form, and the groove for the nails. Tough iron is em- ployed for them, and for the horse- shoe nails, to bear severe usage. Hosiery Manufacture. The word hose meant long stockings, in regard to the garments of past ages ; and on that ground the terms hosiery and stockings became applied indis- criminately. But hosiery, in a manufacturing sense, now means something more than stockings. It is a comprehensive designation for those textile fabrics for whatever kinds of garment intended which are made by a sort of knitting or chain-work, unlike the regular long threads and cross-threads of ordinary weaving ; and therefore gloves, drawers, under-waistcoats, night- caps, Guernsey shirts, &c., are in- cluded as well as stockings under the name of hosiery. The usual hand-wrought machine for this kind of work is noticed under FRAME- WORK KNITTING; but it was not until steam power was brought into requisition that the hosiery manu- facture received its full development. The hosiery machines, which are now an important feature in the trade, bear the same relation to the stock- ing frame that the power-loom bears to the hand-loom. One variety, the circular machine, is important, inas- much as it facilitates the production of seamless garments. In 1867 we exported ^"795, oooof cotton hosiery, ^270,000 of worsted hosiery, and a little in flax and silk. There were at work in the United Kingdom, in the same year, about 18,000 frames and machines narrow, wide, cir- cular, rotary, and warp ; of these, 15,000 were hand-frames, worked in 4,700 shops. Hot- Air Engine. Many circum- stances suggest a doubt whether the steam-engine is the most economical mode of applying heat as a producer of mechanical power. It is supposed that hot air would be a better motor, and hence the construction of many kinds of air-engine, caloric engine, hot-air engine, thermo-dynamic en- gine, &c. It is believed that, be- sides a more economical employ- ment of heat, such engines might probably be found safer from explo- sion, lighter in weight, and less in cost. The experiments of Sir Wil- liam Thomson, Professor Macquorn Rankine, and others have shown that the same pressure at which steam has a temperature of 300 Fahr. would raise air to a temperature of 1 700 Fahr. ; and this opens a view of the subject which was not known to Watt and the other inventors of the steam-engine. Stirling's Air En- gine, invented long ago, and em ployed to drive machinery at the Dundee Foundry, involved the use of cast-iron receivers, hollow metal plungers, coils of small tubing to contain cold water, parallel plates of metal to allow air to pass between them, working cylinders provided with pistons, and small forcing pumps. The arrangement and mu- tual actions of these parts need not here be described, as the engine has been superseded by improved forms. Ericsson's Engine, first brought forward about 1852, had two cylin- ders one for compression, and one for expansion of air. Air was com- pressed in one cylinder to about two-thirds its original volume, and forced into a receiver or magazine. A valve admitted the greater por- tion of this compressed air into the expansion cylinder, where the heat was mostly abstracted from it by a regenerator of wire gauze. A fur- nace placed under the expansion cylinder supplied the heat. The regenerator was a kind of reservoir for heat, receiving it from one body HOT 175 HOT of air, and transmitting it to an- other, and so enabling it to act over and over again as a motive power for machinery. The extravagant anticipations of economy entertained by Captain Ericsson were not real- ised, and engineers were averse to the novelty ; but it has since been found that there is really a saving ot heat, if the apparatus be skilfully arranged. Dr. Joule has investi- gated this matter very fully, and has placed the economy beyond all doubt relatively to the steam-engine. This being so, there is fair ground for believing that some form of hot- air engine will eventually take a position among prime movers of first-class importance. Hot Blast. The air driven into an iron-smelting furnace by the blowing machine (see BLAST) has a tendency, in the first instance, to cool the contents of the furnace by its cold current ; and this suggested to Mr. Neilson the probability that it would be worth while to make the air hot before admitting it to the furnace. This idea has led to the establishment of one of the greatest improvements in the iron manufac- ture the hot blast. Not only is more fuel saved in the furnace than is used in the preliminary warming of the air, but the contents of the furnace can be raised to a higher temperature, thus permitting the fusion of certain kinds of ore which would be infusible by the cold blast. But there is more than this. Not only are fuel, lime, and time econo- mised, and otherwise refractory ores brought into use ; but coal can be used in addition to, or instead of, coke, with a consequent saving of part of the expense involved in coking. These numerous advantages have brought the hot blast into a liigh degree of favour. The air is heated in a kind of stove provided with a series of cast - iron pipes over a fire-place ; the air is made to pass through the tubes (which are 6 or 8 inches in diameter, and arranged like vertical syphons) into two horizontal tubes of larger dia- meter, and thence into a large cylinder. From this cylinder the air is drawn into the cylinder of the blowing machine, whence it is forced into the blast furnace. In most blast furnaces each tuyere or nozzle is pro- vided with its own air-heating appa- ratus ; and from 30 to 35 tons of coal per week will heat to 600 Fahr. sufficient air to make 60 tons of pig- iron. A very scientific mode is sometimes adopted (especially on the Continent, where coal is dearer than in England) of utilising the waste heat of the blast furnace by making it heat the air of the hot blast. The amount of heat thnnm out at the chimney of most of our great furnaces, in the forms of flame and smoke, is something enormous; amounting, it is computed, to 60 or 80 per cent, of the whole heat gene- rated in the furnace. Many plans have been proposed, and some of them tried, for saving this valuable but wasted heat for the purpose here named. One of these plans, by Mr. Budd, of the Ystalyfera Iron "Works, depends upon the construc- tion of peculiar stoves nearly on a level with the top of the furnace. Hot air, from the throat of the fur- nace, passes through flues into a chamber containing tubes filled with the cold air for the blast ; this cold air, being thus heated to 600 Fahr. or more, passes down pipes to the blowing machine, and thence into the furnace. The hot ah- of the fur- nace is not the same air as that of the blast; the former heats the tubes in which the latter is contained. This is rendered possible, because the heat at the throat of the furnace is tremendous, as much as 1800 Fahr. The scientific theory of this mode of hot blast is complete ; the only doubt is in the efficacy of the practical ap- plication. Some kinds of iron, nevertheless, are of better quality HUC 176 HYD when smelted by the cold blast. See further under IRON. Huckaback is a coarse flax fabric, mostly used for towelling ; the mesh is not quite plain, but has something of a damask character. Hydraulic Cement. A cement very useful in hydraulic engineering is made by mixing lime with poz- zuolana. This is a peculiar volcanic stone or lava, consisting mainly of silica and alumina, variously co- loured by earths and metallic oxides found combined with it. Pozzuo- lana has a strong affinity for hy- drate of lime ; and this affinity causes the two to form an insoluble compound. The Romans, who used much Vesuvian pozzuolana in this way, made mortar which has proved more indestructible even than the well-made bricks which they cemented by its means. Terras, or trass, from the Rhine) basalt and trap rock, burnt clay and powdered pottery ware, may all be used as substitutes for pozzuolana. A better known hydraulic cement in England is that usually called Portland Ce- ment, made from chalk and clay obtained from the valley of the Medway. The ingredients are ground up together with water, pre- cipitated, dried, and carefully burnt. The cement made from these ma- terials is exceedingly strong, resisting flexure and crushing in an extraor- dinary degree more so than the Roman cement made from nodules of argillaceous limestone. Rich lime and clay are made into hydraulic cement in France. Chalk, broken into pieces of nearly uniform size, is ground with clay in a large ver- tical mill, 4 of chalk to I of clay, with plenty of water. The liquid mixture is run off into a series of troughs, descending from one to another, and depositing a sediment in each. The fine paste thus produced, when sufficiently firm to be handled, is moulded into small oblong prisms, which, when dried and calcined in a kiln, form the solid ingredient for a very strong cement. (See GYPSUM CEMENT, ROMAN CEMENT, See.) Hydraulic Crane. The pres- sure of water is now applied in an ingenious way to the raising of weights. A head of water is ob- tained, usually by steam-pumping into a tank on the top of a tower. The water, descending in a pipe from the tank, is made by its force to work a piston in a cylinder (usually horizontal, or nearly so) ; and the rod of this piston is con- nected with a chain which passes over the jib of a crane. The motion of the piston thereby becomes trans- formed into a lifting power. By a slight adjustment, the pressure of the head of water can be brought to bear upon the piston of a second cylinder, which causes the crane to rotate on its axis. These cranes, when first used at Newcastle in 1846, by Sir W. E. (then Mr.) Arm- strong, were comparatively feeble; but by successive improvements in- troduced in the hydraulic cranes at Glasgow, Liverpool, Grimsby, and elsewhere, he has given vast effi- ciency to the system. The lifts at some of the great hotels are now worked by this agency. The most profitable working of these cranes occurs when they form part of the machinery of a dock or other large establishment, for which see the next article. Hydraulic Machinery. When Sir W. E. Armstrong found that he could raise a weight by the pressure of a head of water, he soon saw that the principle could be carried further to the opening and closing of dock gates, and to various other mechanical operations for passing ships in and out of dock. If the town reservoirs on the high-pressure system, as at Newcastle and Liver- pool, are sufficiently elevated to give a head of water, the power is derived directly from this source ; if not, a steam-engine is employed to pump HYD 177 HYD up water into a tank on the top of a tower. But there is a third plan, which is now extensively adopted. Instead of height, the pressure of the water is produced by sheer weight. A strong vertical cylinder is filled with water; a solid iron plunger of enormous strength works up and down in this cylinder ; the cross-head of this plunger supports a vessel filled with stones and gravel to the weight of 50 or even 100 tons ; and this weight virtually constitutes the pressure on the water. This apparatus is called an accumulator, because it accumulates and regulates the pressure, which in some in- stances is equivalent to a column of water 1,500 feet high. The lower end of the cylinder is connected with the apparatus, of whatever kind, to which the water-pressure power is to be applied. Raising weights, opening and shutting dock gates, opening and closing swing and draw bridges, loading and unloading railway trucks, hoisting into ware- houses, lifting laden trucks from one level to another, working turn-tables, fec. all can be done by this hy- draulic machinery. The new St. Pancras Depot of the Midland Rail- way (1868) is well supplied with such apparatus. It might be sup- posed that as steam power is neces- sary to develop this water power, nothing could be gained by the use of the latter ; but there are many conveniences in the arrangement, of which the following three are found to be important that the power is always ready in the accumulator; that it can always be used in the exact quantity required, without wasting ; and that it can be practi- cally applied at a very long distance from the spot where the accumulator is placed. Hydraulic Press, or Bramah's Press, is very advantageously used in many branches of manufacture. A strong iron cylinder has a solid plunger working up and down in it. A small tube connects this cylinder with a pump-barrel, in which a piston works as a force-pump. When this pump is set in action, either by manual power or steam power, the movement of the piston causes a small current of water to be driven along the pipe into the cylinder ; the water cannot here find room for itself except by forcing up the plunger. This force becomes almost irresistibly strong ; and a plate or frame, resting on the top of the plunger, is raised slowly and to a small extent. When the arrange- ments above it are such as to form a press for practical use, two hori- zontal plates, one over the other, being brought nearer together, the force is so great as to be hardly conceivable, testing the strength of the mechanism in a severe way. The power of an hydraulic press depends mainly on the ratio between the diameter of the pump- piston and that of the cylinder- plunger. Thelargestofthe.se ma- chines ever known were those con- structed for raising the Britannia Tubular Bridge at the Menai Straits. One of them had a plunger or ram 20 inches diameter, and the metal of the cylinder 1 1 inches thick ; a 4O-horse-power steam-engine was used to work it, and the head of the ram had a lifting power of 900 tons. In the every-day processes of manufacture, the hydraulic press is largely used in oil-mills, cloth- dressing and packing establish- ments, bandana print-works, and numerous other mills and factories. Hydraulic Ram is a machine for raising water, which acts on a very remarkable principle. There is a head of water in some kind of tank, but this is made to drive the water to a still higher elevation. There are various tubes and pipes, orifices, valves, and a vessel filled with air. The descent of water from the tank, with a pressure depending on the height, is made to condense N HYD 178 ICE the air in the air chamber ; and the pressure due to this condensation forces a portion of the water up to a higher level, the rest running to waste. It is a contrivance for uti- lising some power by throwing away the remainder. The chief purpose of the hydraulic ram is shown in the case where a small running stream is used as the source of water to be driven up to the top of a house ; by a due adjustment of the ram, water may be raised to a height thirty times as great as the height of the stream, measured from the base-line on which the apparatus is placed. Hydrometer. This instrument is used (besides its scientific appli- cations) in determining the strength of spirits, acids, oils, and other liquids. If water is mixed in cer- tain proportions (say) with spirit or with sulphuric acid, a gallon of either of those liquids is not worth so much in the market as a gallon in which there is less water ; and therefore it becomes important to have a ready test on this matter. Spirit is lighter than water; sulphuric acid is hea- vier than water ; specific gravity de- notes their relative weights ; and the hydrometer denotes the specific gravity of any intermediate mixture. In one form of the instrument a bulb, weighted with water, is placed in the liquid, with a graduated stem projecting up from it. When the instrument is in water, the gradu- ated stem sinks to a certain depth ; when in a heavy acid, not quite so deeply ; when in a light alcohol or spirit, somewhat more; deeply. In another form, the stem above the bulb has only one graduated mark ; but there are certain weights which, placed in or attached to the instru- ment, assist in determining specific gravities. The Excise authorities (who tax spirits according to the strength), and the wholesale dealers in many kinds of liquids, use various forms of hydrometers, aerometers, and alcoholometers for this pur- pose. Hygrometer is an instrument for measuring the amount of mois- ture in the air. Its use hitherto has been almost entirely scientific, not much applicable to the practical arts. I. Ice House. Ice is useful in so many of the arts of life as a source of cold, that much attention is paid to the means of keeping it in sum- mer below the melting point of 32Fahr. On English rivers and ponds the formation of ice is very uncertain a mild winter almost preventing such formation; but in Canada and the Northern States of America enormous quantities are formed every year. At Wenham Lake, not far from Boston, ice is as carefully attended to as if it were a crop ; and the harvest of this crop gives rise to a very large trade. The cutting of the ice into cubical blocks, and the storing of 20,000 tons at a time in ice houses near the lakes, are skilfully managed. Some of this ice reaches England ; but an enormous quantity .is sent to India and other hot countries. Ice houses, wherever found, are usually built underground. They are, indeed, cellars or vaults instead of houses : by means of double doors, double walls, intervening spaces filled with sawdust or tan, c., the under- ground temperature is kept suffi- ciently cool for the preservation of the ice in a solid form. Somewhat similar arrangements are made in the holds of the ships which convey Wenham ice to India. There is much waste by melting in crossing the heated intertropical regions, but the packers endeavour to reduce this ICE 179 IND waste to a minimum. So successful has the Wenham speculation been, that a similar trade has been or- ganised in Norway and Sweden. It is said that 14,000 tons of ice are annually imported into Hull alone, to pack fish for market. Ice Machine. Where the tem- perature of the air is seldom so low as to produce ice naturally in any- thing like large quantities, an arti- ficial process is now often adopted. In India there are a few nights in winter sufficiently cold to produce a thin film of ice on water, even in the plains of Calcutta, by the use of E roper evaporating vessels, with a ttle water in each ; the natives manage to obtain a small supply by this means. Various other nations, aware of the evaporating power of porous unglazed vessels, have been able to procure thin films of ice by such aids on the cool nights which often follow intensely hot days. In countries where science is more cul- tivated, many freezing mixtures are known which will bring water into die state of ice even in the hottest weather. Snow and salt, ice and salt, snow and chloride of sodium, water and nitrate of ammonia, are among such mixtures. (See FREEZ- ING.) Numerous ice machines have been invented to facilitate the action of these mixtures upon water. The several International Exhibitions have made these machines familiar to millions of persons. Masters, Harrison, Rezet, Siebe, Carre, Kirk, and other inventors have constructed such machines. Vola- tile ether, a solution of ammonia, and other substances are employed ; but in every case there is some che- mical agent (a) which takes away caloric or heat from a vessel of water (), and thereby converts the water into ice. One of these machines requires steam power to produce a centrifugal motion, and therefore it can only be worked profitably on a large scale. Illumination, Artificial. (See CANDLE MANUFACTURE, ELEC- TRIC LIGHT, GAS LIGHTING, LAMPS, &c.) Incense. The chief substances used in the present day for incense in churches, &c., are olibanum, styrax, benzoin, and cascarilla ; there is always a resin with an odo- riferous gum, and the odour is de- veloped by burning. Frankincense is the principal variety. Incombustible Goods. (See FIRE-PROOFING.) Indian Ink is a mixture of very fine lamp-black and size with a little camphor. It should properly be called China ink. The Chinese use it largely both in painting and writin g. India Rubber, or Caoutchouc, is the juice or sap of certain trees, obtained by incisions in the bark. The india-rubber or elastic-gum tree grows abundantly in various parts of Asia and South America. If incisions are made, especially in wet weather, a milky juice flows out, and this afterwards dries to a soft solid state. The natives made this dried juice into boots, bottles, and tubes, long before it was known in Europe. The fresh juice con- sists of only one-third real caout- chouc, the rest being a mixture of albumen, gum, wax, moisture, &c. ; but the main product can easily be separated from the other constituents. India-rubber, when pure, melts at about 250 Fahr. It swells and soft- ens in boiling water, but does not dissolve in it. Melted with linseed oil in the proportion of I to 7, it forms an excellent waterproof com- position for boots and shoes. When vaporised at 600 Fahr., and con- densed into a liquid, it forms a use- ful solvent of resinous substances, called caoutchoucine, which is also valuable as a waterproofing compo- sition. India-rubber Manufactures. The name india-rubber was given to 1 80 IND the substance on account of its use in rubbing out black-lead pencil marks. The other uses which have since been found for it are so numerous as to form an almost end- less list ; but india-rubber, or sim- ply rubber, still remains the familiar name. When melted, it forms an excellent varnish and cement. Two freshly-cut edges adhere so closely by a little pressure as to afford great facilities for quickly making tubes, pipes, &c. On account of its suppleness and flexibility, it is found highly valuable in various kinds of surgical instruments. As it may be stretched out to an enor- mous extent, it accommodates itself with remarkable facility to any vari- ations of surface to which it may be applied. It may be cut into sheets, bands, and threads, applicable to countless purposes. It may be woven with woollen, silk, or cotton threads into those numerous elastic fabrics which are now so well known, and of which the spring sides of boots are so excellent an example. When dissolved in gas-tar oil, and used as a cement between two pieces of cloth, it forms the waterproof cloth now so extensively used for overcoats, leggings, aprons, &c. Elastic bands for papers, &c., illus- trate the enormous stretching which this substance will bear. A globe of india-rubber, softened in water and blown into with the breath, can be expanded into a balloon of almost any degree of thinness. Some of the elastic fabrics are made of thread consisting of a very small filament of india-rubber braided round with silk or cotton ; while others have a warp of gutta percha and a weft of spun fibres. By means of delicate cutting machines, I Ib. of india- rubber may be cut into nearly twenty miles of thread or filament. Very numerous patents have been taken out by Hancock, Sievier, Silver, and other inventors, either for new applications of this useful substance, or for new modes of preparing it. One remarkable novelty isvulcanised india-rubber, which consists of a thorough incorporation of the sub- stance with sulphur. This new com- pound remains elastic at much lower temperatures than simple india-rub- ber; it assumes a horny degree of hardness when prepared in a special way ; it will bear a considerable heat without change of condition. Its uses in the arts are numerous : surgical implements, stereotype pages for printing, taps and screws, a buffer between the rail and the sleeper of railways, buffers for the carriages, noiseless feet to the legs of chairs, noiseless springs for doors, noiseless tires for wheels, air-tubes for life- boats, inkstands, impervious bottles for volatile fluids, springs for locks, racks for window-blinds all are made with various combinations of india-rubber and sulphur. Some experimenters advocate the use of india-rubber instead of gutta percha for telegraphic cables ; but the ba- lance of opinion is in favour of the latter. The imports of india-rubber in 1867 amounted to 80,000 cwt. Indicator, in the steam-engine, is an appendage which gives notice of the mode in which the working is going on : in reference, for instance, to the force of the steam. It acts, like so many other self-recording instruments, by a pencil tracing a line on a sheet of paper, through the revolution of a eylinder ; the length and direction of this line denote the pressure of steam per square inch upon the piston by a certain mode of measuring the dia- grams. Indigro is one of the most cele- brated of all dye-drugs, giving rise to vast commercial and fiscal ar- rangements in India. It is a blue dye, derived from an Oriental plant. When the plants are cut down, they are steeped in wooden vessels for several hours, until they begin to ferment; the water becomes IND 181 IND green ; and, by a further steeping, aided by agitation and the addition of lime-water, the liquid becomes blue, and saturated with granular matter. After subsidence, the blue becomes a paste, which is put into bags to drain ; then put into small cubical boxes to dry and harden, And then packed for sale. The indigo thus produced is a concentration of all the blue colouring matter of the plant. Indigo has been known as a blue dye from very early times ; and it is agreed on all hands that there is no other blue at once so effective and so readily obtainable. The rich, dark, almost purple blue is productive of an amazing variety of tints, and it also forms the basis of black for woollen cloth. Nearly all our indigo comes from India, where it is a heavily-taxed com- modity. After supplying the wants of Hindoo dyers and calico-printers, the dealers send enormous quan- tities to England. 72,000 cwt. was imported in 1867. Industrial Exhibitions. The Society of Arts was the first body in this country to collect specimens of manufactures and mechanism for the purpose of showing the spread of industrial art. This was done by means of the Society's Museum, open to the public at certain times. The French, however, were the first to establish National Exhibi- tions of this kind ; the specimens being collected from all over France, classified and exhibited for a time, and then dispersed. Such displays began in 1798, and followed each other at varying intervals, usuaDy about three or four years apart, until recently. England, Scotland, Ireland, and many continental countries have, in like manner, held numerous Industrial Exhibi- tions. In most instances they have been local, confined to the products of some one town, county, or dis- trict ; and very often they have been technical, confined to the products of some one particular trade. All these Exhibitions, besides affording temporary pleasure, have wrought a certain amount of permanent benefit, by familiarising the public with the characteristics of good workman- ship, and giving a stamp of ap- proval to honest efforts at improve- ment. The late Prince Consort earned the well-deserved honour and credit of making such Exhibitions not merely National, but Interna- tional. He sought to bring specimens of the "Industry of all Nations" under one roof. The memorable dis- play at Hyde Park, in 1851, was the worthy result of the labours which he so worthily commenced. Then followed the International Exhibi- tions at Dublin and at New York in 1853, at Paris in 1855, atBrompton in 1862, and (last and greatest of all) at Paris in 1867. The National and International Fine Arts Exhibi- tions such as those of Manchestei in 1857, Leeds in 1868, &c. do not belong to our present subject : we speak only of Industrial or Manu- facturing Exhibitions illustrations of the labour, skill, taste, and pa- tience displayed in producing the countless articles by which we are surrounded in every-day life. Arising out of the experience derived from these Industrial Exhibitions is the interesting event noticed in the next article. Industrial Scholarships. In 1868 Mr. Whitworth, the eminent mechanical engineer of Manchester, laid aside the munificent sum of ^"100,000 to endow industrial scho- larships. The money, invested in Government Securities, will yield sufficient for thirty scholarships of ^ioo a year each. The recipients are to be admitted after competitive examination. The object is to encou- rage the study of science as applied to the mechanical arts ; and the same persons are to hold the scholarships either for two or three years. The plan is to be carried out under the INJ 182 INK auspices of the Education Depart- ment of the Privy Council, or under a Minister of Education, if any should be appointed. Injector, in the steam-engine, is a modern contrivance for improving the mode of filling the boiler. Un- der ordinary arrangements, a feed- Eump is employed for this purpose ; ut the injector, acting as a substi- tute, is put in operation by simply opening a communication with the boiler. Being entirely independent of the engine, it can operate whether the latter is working or not, and thus has often a special usefulness attaching to it. The difficulty of feeding the boilers of locomotives from the tanks while in rapid mo- tion was one of the circumstances that led to the invention of the injector ; and Mr. Giffard's contriv- ance for this purpose is now coming extensively into use. The steam in the boiler itself is made the agent for forcing the water. Ink. The ink employed for writ- ing is very different from that for printing, the latter bearing much more resemblance to oil paint. There are other kinds, again, which differ from both of these. The chief kinds of ink are made in the following way. Writing Ink. Besides some intense black pig- ment to give the colour, and water to liquefy it, the ink contains a little gum to give a proper con- sistence, and to protect the vege- table black from decomposition. There are almost innumerable re- cipes for black ink, each maker having a favourite plan of his own. The folio wing is one among many : Aleppo galls 6 ozs., sulphate of iron 4ozs., gum arabic 4 ozs., water 6 pints. Boiling, evaporating, settling, and decanting are variously em- ployed in the making. Coloured Ink. By changing some of the in- gredients, red or blue ink may be made instead of black. Either carmine or Brazil wood is used in making red ink, while indigo or Prussian blue is pretty sure to be a component of blue ink. Stephens's Writing Fluid, black or blue, is an ink for which the inventor claims certain advantages in fluidity and permanency. Marking Ink de- pends on the chemical reaction of two liquids, the ink itself and a preparatory solution. The solution is made of carbonate of soda, gum arabic, and water ; the ink of nitrate of silver, gum arabic, Indian ink, and water. The linen or cotton cloth is first wetted with the solution, and then written upon with the ink. The action which ensues causes a black stain or ink to adhere permanently to the fibre. Many other kinds of marking ink have been invented. Sympathetic Ink, of whkh there are several varieties, is invisible when first written on paper, but develops and becomes visible when the paper is warmed before the fire. Indelible Ink claims to defy all attempts to remove it by chemical means. One among many kinds is made of Frankfort black, gum arabic, oxalic acid, some colouring agent, and water. Printers' Ink, always oily, differs in kind according to its in- tended use. For letter-press print- ing the ink is made of boiled and burned linseed or nut oil, lamp- black, and turpentine. For copper- plate printing the oil is less boiled, and the lamp-black is replaced by Frankfort black. Some makers add a little resin, some a little indigo ; some suggest balsam of copaiva instead of oil; but linseed oil and lamp-black are the staple of the ink with which most of our books, periodicals, and newspapers are printed. Some of the work left by the old printers puts to shame many a modern book only a few years old, in the intense blackness compared with the dirty brown of the ink. The modern ink-makers can equal the old, but a craving for cheapness stands in the way. Lithographic INL J Ink. Of this there are two kinds, writing and printing. The former consists of shellac, soap, wax, tallow, gum sandarac, and lamp-black ; the latter of nearly the same ingre- dients, with the addition of black pitch. (See also INDIAN INK.) Inlaying is the insertion of one piece of wood or metal, according 10 a pre-arranged device or pattern, in another, in such a way that the surfaces of the two may be brought to a general level. In what way this differs from mosaic, in which hundreds or thousands of small pieces are combined, will be seen by referring to MOSAIC. Some of the most usual kinds of inlaying are described under BUHL WORK ; JAPANNING ; MARQUETRY; PAR- QUETRY ; PIETRA DURA. Intaglio is simply the reverse of Cameo (which see), the device being sunk in a gem, seal, or en- graved plate, instead of being raised, or in relief. The die that stamps a coin, and the die which produces the embossed queen's head on an envelope, are examples of the in- taglio class. International Exhibitions. (See INDUSTRIAL EXHIBITIONS.) Iodine is a simple substance which, of great interest to the scien- tific chemist, is gradually becoming more and more useful in the arts. It is chiefly obtained from kelp and other forms of seaweed, but some- times from mineral waters. Iodine produces a splendid blue colour with starch ; it forms an element in the iodide of silver, so useful in pho- tography ; and many other of its chemical combinations possess use- ful properties. Iron. This, the most plentiful of all metals, is also the kind most useful to man ; it has been highly prized from the earliest recorded ages. It rarely occurs in a pure or native state, being nearly always smelted from an ore which looks more like stone than metal. Of this ore there are many ; 3 IRO varieties. Magnetic iron is nearly all oxide of the metal ; Hematite, or red ore, is rich in metal, though not so much so as magnetic iron ; Brown ore is an abundant source of iron in France ; Iron Pyrites, as a siiiphuret of iron, is used rather as a source of sulphur than of metal. But Car- bonate of Iron is the ore most abun- dant and important in this country, known under the various names of clay ironstone, black-band, carbo- naceous ironstone, &c. It occurs mostly in the coal formation, gene- rally combined more or less with clay, the proportion of pure iron in the crude ore varying from 20 to 40 per cent. So far as concerns the United Kingdom, South Wales is the richest iron district; North Wales is comparatively scanty, but the quality of the iron is good ; the spot where the counties of Salop, Worcester, and Stafford meet, and for a wide district around that spot, forms a very busy scene or iron industry ; the Forest of Dean produces good hematite ; Derbyshire has a small area of good iron ore; and Northampton- shire bids fair to enter the list before long. The six northern counties all contain iron-works, especially the Cleveland district of North York- shire, and the hematite district of Ulverston. The Scotch iron district stretches east, south, and south' west of Glasgow. Considered as to its qualities, irrespectively of its manufacture, iron owes most of its differences to the quantity of carbon combined with it, which differences also establish the classifying of steel distinct from iron. The matter may be thus briefly stated : Wrought- iron, containing very little carbon, is soft, malleable, ductile, tenacious, easily forged, easily welded, not fusible at the usual furnace heat, and not admitting of much modifi- cation by tempering. Steel, contain- ing more carbon than wrought-iron, is malleable, elastic, ductile, mode- rately forgeable and weldable, fusi- IRQ 184 IRQ ble at the usual furnace heat, and susceptible of being hardened to various degrees by tempering. Cast- iron, containing more carbon than either of the above two kinds, is hard, brittle, easily fusible, but not admitting of forging or welding. Concerning the uses of iron in the arts in other than the metallic state, they are numerous and important. The oxides, carbonates, sulphates, sulphurets, &c., enter into manu- facturing operations in a multitude of ways. When pure, iron has a specific gravity of about 7-8 nearly eight times as heavy as water. The arrangements for sinking mining shafts, making galleries, digging the ore, raising it to the surface, c., are nearly the same for iron as for many other metallic ores. It will therefore suffice, on these points, to refer to MINING. At the mines of Great Britain 10,000,000 tons of iron ore are now raised annually, valued at ^3, 300,000. Iron Calcining 1 ; Ore Boast- ing-. Iron ore passes through a number of processes before it be- comes available for practical pur- poses ; of these, the first is calcin- ing or roasting. When the ore, of whatever kind it be, has been raised from the bowels of the earth, it requires a certain amount of roasting before it can be smelted. The claystone ore, the chief kind in this country, is usually roasted in the open air. Small coal and ironstone are placed in alternate layers till 15 or 2ofe( by 6 or 7 high, and as long as the they form a heap 15 or 20 feet wide piece of ground will permit. The lowest stratum of coal is kindled, and the whole mass becomes gradually heated, burning the coal into cinders, and driving away the water and carbonic acid from the ore j the cooling is allowed to pro- ceed gradually during a period of some weeks. Some qualities of ironstone require the coal to be coked before being used, while some are so rich in bitumen as to roast themselves with very little addition of fuel. Our average clay- stone or clay ironstone loses from 25 to 30 per cent, of its weight during the roasting. Generally speaking, from 3 to 4 tons of coal are burnt in producing every ton of pig-iron, including the portion used in the roasting process. In some districts the roasting, instead of being conducted in the open air, is carried on in flat kilns in certain- respects a better plan. The roasting not only drives away the water and carbonic acid, but also brings the ore into a porous condition which facilitates the smelting process. Iron Furnaces ; Smelting-. The smelting of iron requires the use of furnaces vast in bulk and peculiar in construction. There is no theoretical necessity, it is true, for this magnitude of scale ; but it is found to be more profitable in the end, as economising both fuel and time. The ore, notwithstanding that the water and the carbonic acid have been expelled by roasting, contains a large percentage of other substances, chiefly silicaand alumina, which must be expelled ; lime as well as coal or coke is needed to effect this, the lime combining with the silica and alumina, and leaving the iron free to combine with the carbon of the fuel to form crude or pig-iron. Some ore is of such a quality as to render the use of lime unnecessary ; but the majority of English ores require this addition. The Blast Furnace., (which see) is the structure in which this change is brought about. An immense amount of fuel is consumed in heating a new furnace, or in reheat- ing one which has been out of blast, before any iron ore is thrown in ; and then the gradual filling and smelt- ing go on for a long time ; but when once the furnace has been filled, it is kept at work continuously, day and night, Sunday and week- IRQ 185 IRQ day, for five or even ten years together in such a manner how- ever, as to require as little men's work as possible on Sunday. Some- times the ore, lime, and coal are lifted up to the furnace door from the ground ; but often the levels are such as to permit them to be wheeled direct into the furnace from trucks travelling along a railway. In some of the Staffordshire works the pro- portions are 400 Ibs. of coke and 100 Ibs. of limestone to 336 Ibs. of clay ironstone ; this is the " charge," or quantity thrown in every hour. In one furnace, somewhat differently arranged, blown with a hot blast at 624 Fahr., and 6f inches pressure, each charge consists of 420 Ibs. of calcined or roasted ore, 390 Ibs. of coal, and 1 70 Ibs. of limestone ; and there are 80 of these charges in 24 hours. The three ingredients settle down into the mass beneath, which is much hotter in the boshes than in the body, and still more highly heated at the hearth. The blast, hot or cold as the case may be, is applied (see BLAST ; HOT BLAST) ; and the whole of the solid ingredients become a molten mass, nearly white with heat. The molten metal falls to the bottom of the furnace, with the slag floating on it. At a certain stage in the proceedings the slag flows over a kind of dam, and so out of the furnace ; it is often made to mould itself into large blocks, which are available in some kinds of building and road-making. When the metal itself is quite ready, the furnace is tapped, by removing a plug of refractory clay from a hole in the bottom. Moulds are made in the sanded floor in front of the furnace ; they are channels, some large and some small, communi- cating one with another, and one of them leading from the tap-hole in the furnace. When all is ready, the blast suspended and the plug removed, out flows the metal in a brilliant golden stream, intensely bright and hot, so as to be bearable only by men long accustomed to it. The metal flows into and fills all the channels. The portions of metal which flow into the smaller channels are pigs, those in the larger sows, in the language of the workmen ; and the pigs are connected with the sows by so small an attachment as to be easily broken off when cold. The pigs and sows are allowed to cool gradually; the hole in the furnace is plugged up ; new charges are thrown in, and the blast applied ; and the routine goes on as before. The work of the blast furnace is thus seen to be, to produce pig-iron from ironstone by the rorrrbined in- fluence of coal or coke, lime or limestone, and the hot or cold blast. Iron Refining- and Puddling 1 . Iron, in the state of pig, exhibits many diversities of quality, mostly depending on the quantity of carbon combined with the metal. Foundry metal, dark grey iron, bright iron, molten iron, white iron, are names for several kinds ; while No. i, No. 2, and No. 3 are other designations. Long ex- perience has shown that one kind is best suitable for making small castings, another for large machinery castings, a third for large forgings, a fourth for railway bars, and so on. Each kind presents its own beautiful appearance of colour and sparks when flowing from the tap-hole of the blast furnace ; even the slag or iron cinder tells its tale in this par- ticular. None of the varieties of pig-iron, however, are sufficiently pure for conversion into wrought; they contain silica and other im- purities, which render them brittle, and which must be removed by refining. If there are sulphur and phosphorus in the ironstone, these are mostly removed by the prelimi- nary roasting, for it is difficult to get rid of them afterwards. The refining consists of two successive processes, fining or refining, and IRQ 186 IRQ puddling. For the first, the pigs of metal are thrown into the Re- finery (which see), six at a time, weighing, perhaps, 20 to 30 cwt. Here, by means of a strong heat, the metal is kept in a liquid molten stage for a considerable time ; the silica and most of the carbon are driven off by this means. At a proper stage, after about two hours of this heat, the tap-hole is opened, and the molten iron flows out into moulds, which form slabs about IO feet long, 2\ broad, and 2 inches thick. It is cooled quickly by the action of cold water, and the result is a very hard and brittle iron called fine metal. Thus far the refining has got rid of most of the silica and carbon ; and then comes the puddling to advance it still fur- ther. The slabs of fine metal are broken up with a hammer, and thrown into another furnace. (See PUDDLING FURNACE.) When the metal is here melted, it is kept stirred by the puddler for a con- siderable time, to expose every part of it in turn to the oxidisinginfluence of the blast. The metal seems to boil, and gradually assumes a thick or pasty consistence, then a granular state, and finally the puddler works it up with his rod into balls or blooms, masses of 60 Ibs. or 70 Ibs. each, which are removed from the furnace by means of large tongs. The puddling lasts about 2\ hours, and 4 or 5 cwt. of metal is operated upon each time. The pig-iron loses about 15 per cent, in becoming fine metal, and then about 10 per cent, more in becoming balled or puddled iron. Coke is used as the fuel for refining ordinary iron ; but for tinned plates or for wire-iron charcoal is necessary, being more pure. The balls or blooms require much squeez- ing, hammering, and rolling before the metal assumes the proper state for wrought-iron purposes. It has got rid of most of the carbon, silica, sulphur, and phosphorus, but it is not yet sufficiently tough and homoge- neous. It is either helved or squeezed in the next process. The helve or shingling hammer is a ponderous mass of metal, 10 feet long, and weighing 3 or 4 tons, pivoted near one end ; the head makes a rise and fall of about 2 feet, 80 or 100 times a minute, by steam or water power. A ball of white-hot metal, grasped by tongs, is brought from the pud- dling furnace to the helve, where a succession of blows drives out the adhering slag, and consolidates the metal. Some ironmasters prefer the squeezer to the helve. The squeezer consists of two powerful jaws, opening and shutting like scissors or snuffers ; and the white-hot ball of iron, placed between the jaws, is squeezed instead of hammered. Iron Boiling* and Milling-. One form in which iron is applied is that of cast-iron, used for num- berless important purposes in the arts. The processes by which the metal is brought into this state are described in CASTING AND FOUND- ING, and also in CANNON FOUND- ING, CYLINDER CASTING, &c. Another form which it assumes is that of wrought-iron. The roll- ing of iron is an essential requisite towards its toughness. No sooner has the ball or bloom passed under the action of the helve or the squeezer than, while still red-hot, it is transferred to the rollers, which are of two kinds, roughing rolls and finishing rolls. (See ROLLING MILL.) If sheet-iron is to be made, the rolls are smooth. Sometimes these rolls are placed one above another ; the bar is passed forward between the first and second, and back again between the second and third. The rolled bars obtain various names, such as common iron, best iron, and best cable iron, accord- ing to quality. Some of them are called red-short, which crack when bent at a red heat ; others are cold- short, weak and brittle when cold ; IRQ 187 both of these are regarded as defects. The rolling of vast blooms of iron into slabs, plates, and sheets is only a modification of the rolling into bars, depending rather on the size and shape of the rollers than on the quality of the iron. For one variety of this ponderous work see ARMOUR PLATES. The iron machines, en- gines, apparatus, tools, cutlery, and countless articles of use and orna- ment which surround us in our daily life are more or less noticed under the proper headings. Iron Trade and Statistics. Our national trade in this metal is something enormous. A recent estimate is to the following effect : 257 iron-smelting works in the United Kingdom ; 920 smelting furnaces contained in them ; 5,000,000 tons of pig-iron made from 10,000,000 tons of ore. Then, in relation to subsequent operations, 252 puddling and roll- ing works, containing 6,400 pud- dling furnaces and 730 rolling-mills. What is the value of the 5,000,000 tons of pig-iron when finally con- verted into articles of use and orna- ment it would be almost impossible to say, owing to the wide range in value per ton between large castings and forgings for engineering, and small delicate ornaments. The shipping interest, too, is vastly interested in our iron trade. After supplying home demand, we exported in 1867 no less than 567,000 tons of pig and puddled iron ; 300,000 tons of bar and rod iron ; 580,000 tons of rails for railways ; 81,000 tons of castings; 145,000 tons of sheet and plate iron, and 110,000 tons of wrought-iron in various forms; worth altogether ^13,000,000. Iron War Ships ; Iron-dads. So long as the guns employed in naval warfare were limited to 68- pounders as a maximum, strongly- built timber ships were considered sufficient for the necessities of the IRQ case; but when ordnance hurl- ing shot and shell of 100 Ibs., 200 Ibs., or even 300 Ibs. weight came into use, the bulwarks were no longer adequate. Hence the in- vention of iron-dads, or armour- plated ships. The first actually built were some floating batteries used by the French during the Cri- mean war in 1854; they were not only built of iron, but were coated with thick iron slabs. The English Government, following the example, built eight floating batteries in 1856 : very slow and unmanageable ships. The French, in 1 86 1, converted the 9O-gun timber-built line-of- battle ship La Gloire into a corvette of 40 guns, and clad it with iron slabs 4 1 inches thick. Then it was that the British Admiralty, unwilling that France should keep the lead, commenced a system of iron-clad building which has continued ever since. Numerous modifications of plan have been adopted, to ascer- tain which among them possesses a preponderance of practical advan- tages, (i.) Large timber-built men- of-war, whether finished or not, have been cut down in height, in- creased in length, and clad with 4^- inch armour plates, backed by 30 inches of solid timber. (2.) Some of the timber ships, thus altered, lengthened, and armed, have been provided with solid projecting rams of great weight and power, to pierce an enemy's side. (3.) Some, to render the ship more buoyant, have had the armour plates only over the most exposed parts ; while others have been clad from stem to stern. (4.) Some have had the guns placed in a revolving turret of immense strength, instead of as a broadside in the usual way. (See TURRET SHIPS.) (5.) A plan has been tried in a few cases of notching or bevelling the sjdes of the ship in such a way that the guns may be trained to take a very wide sweep, so as to fire, if needed, much nearer in a line with IRQ r 88 IRQ the keel than is usually practicable. (6.) After many partially-built tim- ber ships were converted into iron- clads, others built wholly of iron were commenced ; and these form the most formidable class of the two. (7.) To ascertain the effect of actual size, the Admiralty have built the vast ships Northumber- land, Agincourt, and Minotaur, each about 400 feet long and 7,000 tons burden, with 5^-inch armour plates. (8.) To ascertain the capa- bilities of the armour without imme- diate reference to the size of the ship, plates have been used 6, 7, 8, and even 9 inches in thickness. (9.) Various modes of arranging the armament have been adopted, as a means of determining whether it will be better to have a moderate number of guns throwing loo-lb. to 2OO-lb. shot and shell, or a few of those monster guns which will hurl from 300 Ibs. to 600 Ibs. of metal against the enemy. A terrible naval war will alone settle these and many other disputed questions. The iron- clads are well illustrated in the mag- nificent ship Hercules, commenced in the Royal Dockyard at Chatham in 1866, and first floated on the loth of February, 1868. Her framework is almost wholly of iron; she is 325 feet long between the perpen- diculars, 59 feet extreme breadth, and mean draught of water, when fully equipped for sea, 24^ feet ; the ram is a solid mass of iron 5 tons in weight. The tonnage is 5,662 tons (builder's old measure). The framework is a very strong combina- tion of girders and ribs, the former longitudinal and the latter trans- verse; and additional stiffness has been given, first, by the provision of an inner bottom, which would be a source of protection in the event of the outer skin being disrupted or baraded ; and, secondly, by five transverse water-tight bulkheads. The building up of the sides of the ship comprises a more ponderous combination of iron and wood than was ever before attempted for such a purpose. The outer iron plates vary from 6 to 9 inches in thick- ness, the latter being several feet above and below the water line, and extending from end to end of the vessel. The belt of 9-inch plates is backed by 10 inches of teak ; inside this is a skin of i^-inch iron ; then 20 inches more of teak; and an- other skin of f -inch iron. The suc- cessive belts of thinner plates are backed with teak of somewhat less ponderous character. The longitu- dinal girders and transverse ribs produce a kind of cellular structure, and the cells are afterwards filled up with some of the teak backing. The weight of armour plating on the sides is 1,145 tons, a quantity in- creased to i, 218 tons by bolts, nuts, washers. &c. The iron in the frame- work of the ship itself raises the total to 4,250 tons ; to which must be added 810 tons for timber. The engines, by Messrs. Penn, are of i,2OO-horse power nominal, capable of being worked up to the enormous equivalent of 7> ooo ' riorse power. Notwithstanding the weight of the mighty fabric, the engines have been planned to give her a speed of 14 knots an hour. There is a central box-battery on each broadside, so constructed that the guns can be trained into a line of fire at right angles to the keel, or at any angle varying from 90 to 15, thereby giving the gunners an immense ad- vantage in attacking an enemy. In- stead of making the strength and weight equal in all parts, the ar- mour and backing have been made most formidable at those parts which are most exposed to hostile shot. This ship has cost not less than 400,000. For the making of the ponderous iron slabs see ARMOUR PLATES. Iron Wood is an exceedingly hard, dense, and heavy kind of tim- ber, derived from various trees of ISI IVO Oriental growth, and used for rud- ders, axles, ploughs, and many other purposes. Isingrlass, prepared from the sounds and air-bladders of the stur- geon, is the purest of all gelatine. It comes to market as a thin film cut into shreds, and is largely used in the arts for various purposes of fining and clarifying. Ivory. This beautiful substance is obtained from the tusks and teeth of certain animals, especially the elephant, narwhal, walrus, and hip- popotamus, the chief being ele- phant tusk. The tusks are hollow at the larger end, and gradually be- come solid towards the smaller or pointed. The African elephant yields the finest quality, after which comes the Asiatic. Many thousand tusks are imported into England every year, especially for use by the cutlers of Sheffield, who employ enor- mous quantities for the handles of knives, forks, razors, &c. The tusks vary greatly in size, from 8 inches to 10 feet long, some reaching as much as 50, 80, 100, 140, and even 170 Ibs. weight ; but the average is about 10 Ibs. It is only in small number that the shed tusks are picked up by the natives for sale ; the animals are mostly killed for the purpose ; and it has been computed that 20,000 elephants are slaughtered yearly to supply Sheffield alone. Hippopo- tamus tusk yields a hard white ivory, much used by dentists for artificial teeth. The narwhal tooth or horn is very hard, and takes a high polish. Fossil ivory is obtained in Siberia from the tusks of the ex- tinct mammoth, sometimes as much as 10 feet long, and weighing 160 Ibs. In the working up of ivory into handles, billiard balls, chess- men, organ and pianoforte keys, veneers, &c., much difficulty is ex- perienced ; for some of the tusks are more hollow than others, some more crooked, some more irregular in colour and texture. The larger and straighter the tusk, the easier it is to work. Thin saws are used to cut up the tusk,, and great tact is needed in arranging the cuts so that the valuable substance may be ap- plied to the best advantage. Each variation in hardness, whiteness, &c., renders the ivory useful for some purposes rather than others ; and it is the ivory-worker's business to determine all these matters as he goes on. He pencils the tusk, after closely examining it, and makes his saw-cuts along the pencil-marks. The turning, planing, polishing, carving, &c., of ivory, depend on the same mechanical principles as those of hard wood ; but the peculiarities and costliness of the substance ren- der great care necessary. The use of ivory for handles and hafts is noticed under CUTLERY MANUFACTURE; HAFTING, HANDLING. The modes of cutting veneers or thin sheets of ivory, for inlaying, miniatures, writ- ing tablets, &c., are treated under VENEER. Besides the articles al- ready named, ivory is used for combs, paper-knives, jelly, ivory- black, copper-plate printers' ink, napkin rings, and numberless small turned and carved ornaments. For these various purposes we require no less than 10,000 cwt. of ivory annually. Ivory can be bleached, and also dyed, by various modes of treatment. It can also be made flexible by treating it with certain acids. A nut somewhat resem- bling ivory is described under VEGE- TABLE IVORY. Ivory Black. (See LAMP BLACK.) JA.C 190 JAC Jacquard Machine. This very beautiful contrivance for facilitating figure-weaving was invented by Jac- quard, a Lyons manufacturer, dur- ing the time of the first Napoleon. Until his day, clumsy and slow- working mechanism was employed to raise and lower the warp threads, so as to admit the weft to be thrown across them ; but his new machine gave precision and celerity to the operation. The Jacquard machine is placed over the loom. Wires, arranged in rows, with hooks at their ends, raise the warp threads, each hook acting upon one thread. The hooks are supported by bars fixed to a frame ; the frame is sus- ceptible of receiving an up-and down motion, insomuch that when the frame moves upwards, the hooks lift up the warp threads. If the threads were raised in regular alter- nation, each being lifted at the time when its neighbour is depressed, the apparatus would be merely suit- able for plain weaving, and would possess no advantage over the plain loom ; but if two or more neigh- bouring threads were raised together as one group, and if those groups were infinite in number, recurrence, and position, all the varieties of the most elaborate figure-weaving might be produced. Now the Jacquard machine effects this grouping in a very ingenious way. A kind of long horizontal box has each of its four sides or faces pierced with a great number of holes, nearly close to- gether. Cards are prepared, each pierced with holes, but not so abun- dantly, in such a way that when a card is placed on a surface of the box, some of the holes in the latter coincide with those in the former, while others are covered or closed by the unpierced parts of the card. A large number of cards, 100, 500, 1,000, even 20,000, are required for an elaborate pattern, the perfora- tions in each card bearing relation to some one definite part of the pat- tern. The cards for one pattern are so linked edge to edge as to form a kind of endless chain, which passes over the box ; and when the box is made to rotate on a horizontal axis, each card in turn assumes a vertical position. The box not only slowly rotates, but has a pendulum motion, making one swing of the pendulum every time a new card comes into a vertical position. When the box swings, it strikes against the ends of the wires ; some of the wires enter the holes without being moved, but others, coming butt against the unperforated parts of the card, are forced to move a little way in the direction of their length. When they move, they lift the warp threads to which they are respectively at- tached. It becomes evident, there- fore, that the stamping of the holes in the cards is an important pre- liminary operation. The weaver has nothing to do with this. A woman or girl, with the design or pattern before her, transfers this pattern to a series of warp threads fixed in a small frame by means of a long needle which passes a weft thread over and under them in determinate order ; the stamper then, by the aid of a small stamping machine, punches holes in a card according to an order suggested by these bits of weft thread ; and so on with all the cards in succession. Patterns often require 3,000 cards each ; and one particular instance required 24,000. The principle established by Jac- quard has been varied in many ways two boxes at work at once, to expedite the process ; three or four boxes, to increase the celerity still further ; a kind of barrel-organ JAG 191 JET studded with pegs capable of being shifted to any arrangement, instead of a box and perforated cards ; the sub- stitution of thin sheet-iron for cards ; the substitution of an endless band of paper for the cards, &c. M. Bonelli, an Italian engineer, has re- cently invented an electric appa- ratus to work with the Jacquard, under the name of the Electric Loom. The design is represented, not by holes in cards, but by alternations of conducting and non-conducting surfaces in metal plates. The plan is scientific and beautiful, but has not yet come much into use. Jaggery is the name given in India to sugar obtained from the sap of many kinds of palm and cocoa- nut tree. Palm wine is fermented, and arrack distilled, from jaggery. Japan Earth. (See TERRA JA- PONICA.) Japanning-, in some of its varie- ties, is simply applying a coat of varnish to an article of use or orna- ment ; but in other cases it com- prises the formation of a much thicker layer. The Japanese, from whom this art is named, make inci- sions in the trunk of a particular tree, from which a juice exudes ; this juice, cream-coloured at first, deepens to black on exposure to the air, and then becomes japan or japan varnish. The juice, thick- ened with the charcoal of burnt wood, is applied as a paint in many coatings to the surface of wood, metal, or other material, being dried in the sunshine after each coating. A polishing with a smooth wetted stone makes it hard and brilliant, and then it is ready to receive any adornment which the native artists choose to apply to it, either in co- loured paints or in gold and silver leaf. In England the name of japan. is given to a paint made of ivory- black and a particular kind of var- nish. It is generally black, but may be mixed with paint, oils, varnishes, and turpentine to produce a great variety of effects, especially to imi- tate tortoiseshell. Sometimes an ornament is produced by transfer- ring an engraving or drawing to the japanned surface. A kind of inlaying with mother-of-pearl is frequently effected in japan-work, on a ground of papier-mache or metal. The mother-of-pearl, cut to the required device, is laid down upon the groundwork ; repeated coatings of japan are applied to the whole sur- face, until the thickness of the japan is equal to that of the mother-of- pearl. The japan is then rubbed or scraped off the mother-of-pearl, but not off the ground, wheieby all is brought to one level surface. A kind of turpentine paint, used instead of oil paint for deal furniture, is sometimes called japan ; and japan-gold size is the name of a varnish or cement used in attaching leaf-gold to some articles. The principal trade of ja- panned ware is centred at Birming- ham and Wolverhampton, where coal boxes and scuttles, tin canisters, and numerous other articles in ja- panned metal are produced. For cheap ware a single coating of the black varnish suffices ; but the bet- ter kinds are wrought up to a fine polish by the aid of rotten- stone and Tripoli powder. Jasper. (See GEMS AND PRE- CIOUS STONES.) Jerked Beef. (See CHARQUI.) Jet is a beautiful black mineral, found near Whitby, in Yorkshire, and in other places. It is a kind of coal, of the pitchy or bituminous variety, but harder and smoother than any other kind. At Whitby there is a regular manufacture of it into earrings, necklaces, brooches, bracelets, chains, small boxes, chim- ney ornaments, and various trinkets. It has a tendency to split by heat- ing while being worked, and on that account requires careful manage- ment. Imitation jet is made of black glass, hard black wax, and other substances. JEW 192 JUN Jewel; Jewellery. Gems and precious stones are often considered to be jewels in the proper sense of that term ; but gold-work combined with them, or even small gold-work without any stone at all, obtains the same designation. A lapidary (see LAPIDARY WORK) prepares the costly stone by various processes of grinding and polishing; and then the jeweller, by delicate operations of wire-drawing, flatting, stamping, chasing, soldering, burnishing, &c., and the use of foil (see FOIL), works up the gold and the stones into jewellery. At Birmingham an immense amount of cheap jewellery is made, by reducing to the smallest possible thinness the layer of gold upon a body of cheaper metal; while every variety of glass, enamel, and crystal is made to imitate gems and precious stones. It has been com- puted that this wonderfully busy town employs no less than 7,500 persons, and uses up ji, 250,000 worth of gold, silver, and jewels, in the manufacture of cheap jewel- lery and ornaments. Jewelling. What the watch- maker calls jewelling' a watch is not adorning it, but applying small bits of gem for the pivot-holes. These holes would be worn away if made of metal ; and therefore small bits of diamond, ruby, sapphire, chry- solite, and other gems are fixed into little sockets, and drilled with holes to receive the ends of the pivots. This is very delicate work, requiring tact and discrimination. A watch "jewelled in four hole? " has four such pivot-gems, and so on. Joinery. Some of the names given to pieces of wood, as noticed in CARPENTRY, are applicable also to joinery ; but there are in addi- tion many others to denote the vari- ous parts of doors, windows, panel- ling, partitions, balusters, cupboards, and the like. The carpenter de- pends very little upon the plane, whereas a choice variety of planes is indispensable to the joiner, not only to give smoothness to all the pieces employed, but to give shape to most of them such as mould- ings, headings, and filletings of va- rious kinds. On the other hand, the carpenter needs much aid from nails and bolts ; the joiner relies rather on glue and joints. Machine joinery, so to speak, has extended largely within the last few years. We allude to the establishment of large factories, in which steam- worked machines are employed in sawing, planing, doweling, tenon- ing, grooving, and otherwise treat- ing timbers for the making of doors, windows, and other articles of joinery. Such articles can be pur- chased in any quantity, and many builders now keep a stock of them in readiness instead of making them by hand as wanted. (See further under WOOD-WORKING MACHINERY.) Joists. (See FLOORING.) Juniper. The wood of this tree is applied to many purposes in the arts. According to the species of which^wwz^risan extensive genus, one kind of wood is yellowish red, hard, and fragrant, and is used for turnery and veneering ; another kind (known as cedar) is used for the rods of black-lead pencils ; while a third, on account of its repelling the attacks of insects, is valued as a lining for cabinets, &c. The berries are used for flavouring gin. The bark is sometimes made into ropes, the root fibres are woven into baskets, the oil of the nut is used in medicine, and the dry twigs and roots for fumigation. Junk is the familiar name for salt meat packed in barrels for use on shipboard. A parliamentary paoer states that, in the official year 1867-8, 3,113 tierces and 3,013 barrels of beef were pickled or cured in the Government Victualling Yard at Deptford. As the tierce holds 304 Ibs., and the barrel 208 Ibs., the total quantity cured was about a JUT it million and a half of pounds. The total cost, including package, salt, and labour, was ^9 6s. per tierce, and ^6 8s. per barrel. Jute is a material which has re- cently come very largely into use for woven goods, on account of cer- tain economical qualities which it possesses. The jute plant is not of English growth ; it comes from abroad, chiefly from India, where it grows rapidly, and calls for very- little care in cultivation. Like flax and hemp, the portion applied to textile purposes is the greater part of the fibrous stem. When ripe, the plants are cut down near the ground, and steeped in water for a week or more, when the fibres can be separated from the woody por- tion. By referring to FLAX DRESS- ING and HEMP MANUFACTURES, the separating and cleaning pro- cesses, as applied to jute, will be easily understood. It is pressed into bales of about 300 Ibs. each. The India produce now amounts to 600,000,000 or 700,000,000 Ibs. of clean fibre annually. The Hindoos make their gunny bags (see GUNNY CLOTH; GUNNY BAGS) of jute cloth. In England the jute manu- facture was hardly known till about 1840; but now steam power is ap- plied to it on a very large scale, es- pecially at Dundee. As jute is cheap, spins well, and looks glossy when woven, it has come greatly into fa- vour, some of the mills working up as much as 1,000 bales of it every week. The main use of it is for sacking and bagging; other uses are for sheetings, mattings, ducks, and carpetin g ; and in combination with the more expensive fibres of cotton, wool, flax, and cocoa-nut. It dyes easily, but the colours do not wear well. Jute Manufacture. The fol- lowing are the chief processes after the jute reaches the factory. Oiling. The bales being opened, the jute is spread out on a table, sprinkled with J JUT oil and water, allowed to remain a day or two, and pressed between rollers ; this renders the fibres soft and pliable. Breaking. The jute is passed between toothed rollers, the teeth of which bring the fibres nearly parallel, and arrange them into a sort of ribbon or sliver, and then between two other rollers with finer teeth. These two machines are called the breaker card and the Jinisher card. Drawing. The slivers received from the finisher card fall into cans, whence they are subjected to the action of the drawing frame. This acts like the similarly - named machine in the cotton manufacture drawing out, narrowing, and thinning the slivers. Roving. In the roving machine the sliver receives a slight twist, and is wound upon bobbins. Spinning. This is done on the throstle plan, not the mule (see SPINNING), the throstles making 3,000 to 4,000 revolutions per minute. Weaving. After winding the warp yarn on large bobbins in the winding ma- chine, placing it on the loom-beam by the beaming machine, and wind- ing the weft yarn on the pirns of the shuttles by the pirning machine, the spun threads of jute are ready to be woven into cloth. Here it need only be said that the loom and the shuttle are larger and stronger for jute than for cotton, as the material is for the most part worked up into coarser fabrics. In jute the finest yarns bear the lowest numbers, whereas in cotton they bear the highest. So large has this trade now become, that 1,600,000 cwt., or 180,000,000 Ibs., of jute was imported in 1867. About that time, in Dundee alone, there were 60 jute factories, having 100,000 spindles and 5,000 power-looms, and employing 20,000 hands. Mr. Cola states that, for a jute factory comprising 1 6 double spinning machines, of 2,000 spindles alto- gether, with 100 looms, fitted for o KAN 194 KNE weaving bagging and sacking, the v\ hole of the plant would cost about j"2 1,000. Of this sum ^17,000 would be for the working machinery, and ^"4,000 for steam power and mill gearing. K. Kamptulicon is a substance in- tended to present certain advantages over painted canvas as a floor-cover- ing. It is made of cork reduced to a fine powder, india-rubber, linseed oil, and one or two other substances. These ingredients are kneaded up into a kind of dough, which is pressed out into sheets by rolling with steam-heated cylinders. When cold, these sheets may at once be used as a floor-covering, or may be painted with any ornamental device. It forms a more noiseless, elastic, and dry floor-covering than oil-cloth. Kelp is one of several kinds of seaweed from which soda can be prepared. Barilla, one form of crude soda, is made in France and Spain from the semi-fused ash of the salsola soda, found on the seashores of those countries. Varec and Sali- cor, two other kinds, are made in France. The English name, kelp, has been given indiscriminately to the seaweed as picked up, and to the ashes after they have been burnt ; but practically the ashes form the kelp. Early in the present century, when there was a very high duty both on barilla and on common salt, kelp was made on a large scale on the northern shores of Scotland ; and a rental or royalty was given for all the seaweed found on the shores ; but the removal of the duty on salt, and the very small price at which that substance can be purchased, have caused soda-makers to employ salt instead of kelp, insomuch that the gathering of seaweed on the Scottish shores hardly repays the trouble. Kermes is a kind of inferior co- chineal, derived like it from insects, and employed in dyeing scarlet. Kerseymere is a woollen cloth which has a twill given to it in weav- ing. (See TWILL.) Kiln. (See BRICK MAKING, ENAMEL, LIME KILN, MALT AND MALTING, POTTERY, &c.) King's Yellow is a yellow pig- ment made of orpiment and arsenious acid. Kino, one of many kinds of juice or gum which exude from trees in the tropical regions, comes to Eng- land in the form of small, brownish, glittering fragments. It is used by us chiefly in medicine ; but the Hindoos largely employ it in dyeing cotton of a nankeen colour. Kirschwasser, sometimes con- founded with cherry brandy, is a cherry liqueur, made by pounding the pulp of cherries, fermenting, adding the broken stones or kernels, and distilling. It forms a favourite drink in Germany, but is not much known in England. Kneading: Machine. Under BREAD MAKING it is stated that the dough for ordinary loaf-bread is usually kneaded in a very un- couth way by a pole or lever jerked up and down. The process is slow, dirty, and wasteful, and ought to be superseded by one or other of the kneading machines which have been recently invented. Some of these act by means of verti- cal knives on a horizontal rotating axis ; some have a vertical mixer and horizontal blades ; some re- semble a vertical clay-mixer ; while one for domestic use has a kind of pestle-and-mortar action. It has been distinctly ascertained (i), that kneading by machine produces dough well mixed and perfectly clean ; (2), that it is performed in a shorter KNI 195 LAC time than by the common process, and therefore lessens the long hours of labour in the bakehouse ; (3), that it is healthier, by lessening the inha- lation of flour-dustand carbonic acid'; (4), that the men are called upon for a less exercise of physical labour; (5), that there is no waste of flour, because the dough is in a closed receptacle ; and (6), that every particle of flour receives its due admixture with water, thus rendering the bread more palatable and digestible than the loaf-bread ordinarily made. Knife-cleaning-Machine. There are many contrivances for this pur- pose, of which the three following illustrate the general character, (i.) Kent's machine has a horizontal iron spindle or axis ; a winch handle to make this spindle rotate ; two rollers or discs that rotate with the spindle ; and a layer of bristles on the rollers. A knife is introduced into the machine in such a way that the two surfaces of the blade are cleaned by friction against the bristles on the rollers. (2.) Masters's machine acts in a similar way, but with a somewhat different action of the rubbing surfaces. (3.) Price's machine has two horizontal drums, one within the other ; the outer sur- face of the inner drum and the inner surface of the outer are covered with leather or felt. The knife is intro- duced into the machine in such a way that the blade is between the two drums, and is acted on by both. Knife Manufacture. (See CUT- LERY MANUFACTURE.) Knitting- is the original process from which the great manufacture of hosiery has sprung. While, in weav- ing, many threads cross each other at right angles, in knitting, one thread is repeatedly looped or twisted round itself. In its simplest form it is one of the easiest of processes ; in its larger developments it gives rise to the important industry noticed under FRAMEWORK KNITTING and HOSIERY MANUFACTURE. Koh-i-noor. (See DIAMOND.) Kreasote. (See CREASOTE.) Kumiss, or Kaumiss, is an in- toxicating drink made from fer- mented mares' milk. The Kal- mucks indulge largely in it. Kyanising- is one of the modes of preserving timber from decay. It was patented by Mr. Kyan in 1832, and consists in- steeping the wood in a solution of bichloride of mercury or corrosive sublimate. There is some action produced on the albumen of the wood by this substance which changes its cha- racter, and renders it less liable to decomposition. The wood so treated becomes, however, more brittle and less flexible than before. (See also BURNETTISING, and TIMBER, PRE- SERVATION OF.) L. Lac is the name of an Oriental in- sect, and the same name is appro- priated to a valuable substance which it supplies to the arts. The insect lives upon the sap of a par- ticular tree, which gives a purple red tinge to the whole body ; and thousands of such insects glue them- selves to the twig of a tree by the same gum or sap. At a particular season of the year the gatherers cut down the twigs, and obtain all the lac or gum from them, and from the bodies of the insects, by processes of steeping, melting, pressing, dry- ing, &c. The substance thus obtained is called shell-lac, or shellac, a sort of flaky orange-brown gum. Button- lac consists of drops that fall during the preparation of the shellac. Plate-lac is in larger flattish masses. Stick-lac consists of the twigs them- selves, broken into short pieces, with the insects adhering to them. LAC 196 LAC Seed-lac is composed of the very smallest bits, shaken from the trees by winds and other disturbing causes. Lac-dye is the coloured substance from the body of the insect, obtained by solution, sediment, &c. Lac-dye is used in producing the scarlet colour of cloth for soldiers' coats ; but all the other varieties of lac are employed in making varnishes, lacquers, and polishes of numerous kinds, for which the gum is highly valued. Lace. This beautiful article is one of many kinds of textile goods in which the mesh is formed by a looping or linking of threads. As in net, in hosiery, and in crochet, so in lace; the threads, instead of crossing each other at right angles like the warp and weft of ordinary woven ; cloth, are twisted one around an- i other in a peculiar way. The thread may be of wool or silk, of flax or cotton, of silver or gold ; the build- ing up of the fabric, so to speak, is in principle independent of the pre- cise kind of material. That some such work was wrought by the high-born ladies of early times is clear enough, but it is not quite clear in what way the process was conducted. The finest kinds of modern lace are made upon a pillow orcushion. The pattern, drawn upon parchment or paper, is placed upon the cushion. Pins are stuck through the pattern into the cushion, sufficient in number and arrangement to .follow the device. Bobbins filled with fine thread are provided, and so ranged round the cushion that the threads can be twisted round the pins. The bob- bins are taken up by turns, and passed from right to left and from left to right, so that the threads may intertwine ; and according to the rule or order in which this is done, so is the character of the mesh de- termined. If the thread is of uni- form thickness, and the order of working also uniform, a plain net is produced ; but if a thicker thread called gimp is employed in addition, then those complicated and beautiful patterns are produced to which the name of lace is given. Under BOBBIN NET are given notices of that won- derful manufacture which has grown up in Nottingham and its vicinity for producing lace wholly by ma- chinery. Here we need only say that the two kinds are often com- bined hand-lace ornaments being worked upon a machine-lace ground, or a hand-lace border on a machine- lace centre. Numerous names are given to lace, some purely technical, some derived from the names of places where they were first made. Brussels Ground has an hexagonal mesh, with a pattern worked sepa- rately and fastened on by the needle. Brussels Wire Ground is of silk in- stead of flax, with a kind of arched mesh. Mechlin has an hexagonal mesh, with the pattern worked in the ground. Falencienneshas an irregular hexagon, with the pattern worked in the ground. Lisle has a diamond- shaped mesh. Alengon has an hexago- nal mesh, but is of inferior quality. Alen^on Point has octagonal and square meshes alternately. Brussels Point has the net or ground made by bobbins on the pillow, but the pattern worked by the needle. Honi- ton is a beautiful pillow lace, either used for sprigs and borders, or sewed by hand on machine-made net. Limerick, Tambour, and Bri- tish Point are more or less close imitations of Honiton. There was an estimate a few years ago that 25,000 women and girls are engaged in pillow-lace making in the United Kingdom. Lacquer; Lacquering-. Lacquer is a varnish for metal, as distin- guished from the numerous var- nishes for wood. The ingredients are shellac, gum, sandarac, tur- meric, arnatto, dragon's blood, gamboge, turpentine varnish, alco- hol some among these, according to the recipe which may be in favour. The metal usually lacquered is brass, LAK 197 LAM and the purpose is to make it look as much like gold as possible. Heat is necessary to insure the adhesion of the lacquer to the brass. Lake is often supposed to be a beautiful crimson colour ; but tech- nically the word has a wider mean- ing, comprising all combinations of alumina with organic colouring mat- ters. There are red lake, crimson lake, purple lake, yellow lake, and several others. Alum is usually the form in which the alumina is em- ployed : the alumina draws out the colouring matter from a solution of the organic substance, be it animal or vegetable. Thus, alum acting upon cochineal produces the beau- tiful carmine lake; while other lakes result from the action of alum upon Brazil wood, madder, yellow berries, arnatto, &c. The lakes thus produced are used as pigments by calico-printers and paper-stainers. Lama, or Llama, is the wool or hair of a South American animal ; it is not quite equal in fineness to that of the alpaca (a native of the same region), but is applicable to the same purposes. Very little real ilama or alpaca reaches England, the goods sold under these names being more frequently sheep's wool. Lamp-black is a kind of sooty charcoal. In the distillation of tur- pentine from various kinds of resin, the substance left in the still be- comes a source of lamp-black. When burned in close iron vessels the resin gives off a dense smoke, which passes into chambers in which sacking is suspended ; the smoke collects on the sacking as a black soot, which is swept off and becomes lamp-black. It can also be prepared from the smoke of lamps, and indeed it acquired its name from this circumstance. By a subsequent heating in close ves- sels the lamp-black becomes much purified. Some kinds of coal may be made to yield coarse lamp-black, used for rough purposes. Ttie usual kind is one of the ingredients in printers' ink, blacking, paint, &c. Spanish-black is made from cork ; -vine-black from vine tendrils ; peach- black from peach kernels ; ivory- black from bone ; and Frankfort- black from many of these substances combined in each case the black being collected as a kind of soot. Lamps. The mechanism to in- sure the proper flow of oil or spirit to the wick has led to great varieties in the construction of lamps. One familiar form is described under AR- GAND LAMP. Another, the Carcel, is very scientific, seeing that it has clock-work to regulate the equable flow of the oil, supplying equal por- tions in equal times. But the real carcel principle is seldom acted on, as the lamps are very expensive, and are liable to get out of order. The Moderateur, or Moderator, is almost as effective as the carcel, without being so costly or so delicate. A spiral spring, acting upon a piston, tends to press it constantly down- wards, and to force up oil from be- neath the piston through a small tube to the wick. Subsidiary ap- paratus insures the renewal of a supply of oil beneath the piston, the return to the vessel of any oil which overflows the wick, and the regulating or " moderating "accord- ing as the tension of the spring in- creases or diminishes. Thenumerous lamps bearing fanciful names, such as the Solar, Meteor, Stella, Sinum- bra, Vesta, Gem, Victoria, Hydro- static, Paragon, &c., are peculiar in relation rather to the liquid fuel used in them than to the mechanical con- struction of the lamp itself. There are many such liquids now in use as substitutes for whale oil; derived (I), from turpentine and other tree resins; (2), from rock-oil springs and wells ; (3), from bituminous shale ; and (4), from the tar refuse of gas-works. The lamp manufac- ture constitutes a large and impor- tant item in Birmingham industry. LAN 198 LAR For the Miner's lamp see SAFETY LAMP. Lance "Wood, being light and elastic, is found useful for gig shafts, archery bows, surveyors' rods, bil- liard cues, c. Lapidary Work is that of the worker in gems and precious stones. As the substances operated on are at once very hard and very costly, peculiar mechanical tools and pro- cesses are needed. Lapidaries have established certain degrees of relative Jiardness'm. minerals : about4OO kinds have been compared ; ten degrees of hardness have been established ; the kinds have been placed under the classes which they best suit ; and a type or representative variety has been selected for each class. Any mineral in one class can be scratched by any one in the next higher, class, but cannot scratch it. The hardest metal is hardened steel ; this is in Class 8. There are harder minerals in Class 9 (ruby, sapphire, corun- dum, &c.) ; and still harder in Class 10, which is occupied alone by the peerless diamond. These degrees of relative hardness determine the processes of the lapidary, which are of three kinds, cutting, grinding, and polishing. The lapidary's bench has a small wheel which rotates on a vertical axis. This wheel, called a mill, is the slitting, the roughing, the smoothing, or \h& polishing mill, according as it is made of metal, willow wood, mahogany, list, wood covered with buff leather, &c. The powder spi'inkled on the mill mainly determines the kind of work that shall be done ; diamond powder, emery, and rotten-stone being the chief sorts employed. Sometimes, but not often, splitting can be effected by means of natural cleav- age in the stone. More frequently stones are divided into pieces by means of a thin iron wheel called a slicer, the edge of which is touched with diamond powder, and is used like a circular saw. Where a stone is ground down into shape without splitting or slicing, it is ap- plied to the flat surface of a hori- zontal mill or revolving plate, mostly metal, touched with diamond powder or emery. Whether grind- ing or polishing, the principle of action is much the same ; the flat side of a revolving mill or disc is touched with powder, and the stone is held against it in various ways. The powder is mixed with oil, or with water, and applied as a kind of paste. In grinding away the far- famed Koh-i-noor, to give increased brilliancy by a better arrangement of facets, it was held against a mill or disc rotating 2,000 times in a second ; the rotating was produced by steam power, and the process was continued during several weeks. As a general rule, slitting is done with diamond powder and oil on an ircn mill, grinding with emery powder and water on a leaden mill, and polishing with rotten-stone and water on a tin mill. Lapis Lazuli is the name of a mineral found in various parts of Asia, having rather a complex che- mical constitution. It is of a beau- tiful blue or azure colour, and from it Ultramarine (which see) is made. Larch. (See TIMBER.) The very useful wood of this tree is largely employed for railway sleepers, for ship-building, and for many other purposes, on account of its power of resisting the action both of water and of worms. The bark is used in tanning. Lard, the fat of the hog, besides being used for culinary purposes, is subjected to processes whereby stearine and oleine are obtained from it. The formerbecomes available for making stearine candles ; while the oleine, or lard oil, forms an excel- lent lubricant for machinery. The animal stearine and oleine from the ! great hog-curing establishments at i Cincinnati, and the vegetable stea- rine and oleine from the African LAT 199 LEA palm, form valuable additions to the tallow imported by our manu- facturers. It shows how large must be the consumption of this article that in 1867, besides home supply, we imported more than 250,000 cwt. from abroad. Lathe is the apparatus which gives a revolving motion to an ar- ticle of wood or metal while being turned. In the Centre Lathe the work is supported at both ends, while the cutting tool is applied at the space between them. By means of puppets, or short upright posts, an iron pin, and a screw and nut, two sharp steel points are made to stick into the ends of the work, and hold it fast. A treadle, worked by the foot of the turner, causes the piece of wood or metal to rotate rapidly. A horizontal rest supports the tool during the work. The Chuck Lathe supports the work only at one end, thus enabling the turner to apply his tools to the other. Pieces called chucks are used, screwed up to the end of a man- dril ; each chuck being adapted to hold a particular kind of work. It is especially for doing hollow work, such as the insides of wooden bowls and cups, that the chuck or mandril lathe is useful. Other names are given spindle, mandril, pole, hand- wheel, foot-wheel, power, bed, bar, c. to lathes of various kinds. Some are turned by a foot- treadle, some by a hand-wheel, some by steam power. Some are small and simple enough to turn a little wooden bobbin ; while others, in the great engineering workshops, are so powerful as to turn vast wheels and cylinders of iron and steel. For the practical use of the lathe see TURNING. Laths. The laths used in making lath-and-plaster walls, ceilings, &c., are made either of Norway fir or Canada deal, sometimes split, at others sawn, the latter being the more regular of the two. Slaters' laths are usually longer than plas- terers'. Latten was an old name for sheet brass ; it has been superseded by other terms. Launching*. Most ships are built with the stern towards the river or sea, in a slip or dry dock. The level of the slip descends towards the water, and the ship is built upon timber supports of a suitable kind. When ready for launching, the ship is on a kind of cradle which rests on greased timbers ; these tim- bers, when various subsidiary ar- rangements have been made, slide over other greased timbers, and carry the ship out into deep water. When the weightiest of all ships, the Great Eastern, was built, she was broadside to the river, instead of end-on; the incline was not quite sufficient, and the huge fabric, in- stead of gliding down, was driven or forced into the water with tremen- dous power, after an unexpected de- lay of many weeks, and an extra expenditure of many thousand pounds. Lead. This metal derives its use- fulness in the arts mainly from cer- tain special properties of its own. It is flexible, non-elastic, can be rolled into thin sheets or drawn into thin wire ; it is soft enough to leave a black streak on paper ; it is bluish white in colour, and very lustrous at a newly-cut surface. It melts at about 612 Fahr., and goes off in vapour at a red heat. Some kinds of water corrode lead, and acquire poisonous qualities from it ; hence the employment of leaden cisterns and pipes ought to be made depend- ent on the kind of water. Lead is obtained tolerably pure by the smelting process presently to be de- scribed, and then many oxides and salts can be made from it. One oxide is called litharge or massicot ; another red-lead or minium; a combination of sulphur and lead forms chrome yellow ; while car- LEA 200 LEA bonic acid and lead form white-lead. (See CHROME YELLOW; LI- THARGE; RED LEAD; WHITE LEAD.) Lead is rarely found in a pure state ; it is nearly always com- bined with other substances. The most abundant ore, and that from which our supply is chiefly obtained, is galena, orsutyhuretoflead, found embedded in various kinds of rocks ; it contains about 17 lead to 3 sul- phur, and a portion of silver gene- rally sufficient to pay for extraction by a separate process. Mr. Robert Hunt estimates the quantity of lead ore raised annually in the United Kingdom at about 90,000 tons. Lead, De-Silvering-. (See SiL- VER-LEAD.) Lead Manufacture. When the lead ore, galena, orsulphurethas been brought up from the mine, picked, broken, washed, and cleansed (see ORE DRESSING), it is ready to have the metal extracted from the earthy impurities by the following pro- cesses. Roasting. Different me- thods of roasting and smelting are followed in different districts ; but in Northumberland and Cumberland, where there are many large lead mines and lead works, the following plan is usually adopted : The ore is roasted on a long flat hearth covered by a low arch, being one of the many varieties of reverberatory furnace. About 10 cwt. of ore is exposed for three hours to a heat which will partially oxidise and get rid of the sulphur, carrying with it some of the antimony and other substances. Smelting. The roasted ore is thrown into a peculiar kind of furnace called a Scotch furnace or ore-hearth; neither like a rever- beratory nor a smelting furnace, but being a rectangular chamber, supplied with a blast of air from the back, and an opening at the lower part of the front where the molten metal may flow out. With the roasted ore is introduced a cer- tain proportion of browse (ore only partially reduced at ihe preceding smelting), coke, and coal. Here"^ by careful watching, heating, and stirring, the lead (with whatever silver it may contain) is separated from nearly all the other compo- nents of the ore, and is received in moulds, which give to it the form of pig-lead. Much lead goes off from the smelting furnace in the form of fume, wasting the lead itself and the silver it contains, blasting the vegetation all around, and injuriously affecting cattle. Va- rious plans are adopted for lessening this evil : such as conveying the lead fume into large chambers hav- ing a shower of water descending from the roof, causing it to pass through vessels of water that will absorb some of the impurities, or making it pass through a series of chambers one after another. All these methods effect some good; still a lead-smelting establishment is an unhealthy place. For Mr. Pat- tison's beautiful plan of extracting the silver from pigs of lead see SILVER-LEAD. Two of the nume- rous forms into which metallic lead are brought are noticed in the next article and in SHEET LEAD. There are about 30,000 tons of lead and lead manufactures exported annually out of a total make of 70,000 tons. Lead-pipe Making 1 . Among the many ways of making pipes and tubes, that which is employed in the lead manufacture depends for its characteristics on the pro- perties of the metal. A short thick cylinder of lead is cast, with a bore of the proper size. A steel man- dril is thrust through the bore, and then the cylinder is passed many times between rollers having grooved' surfaces ; smaller and smaller grooves are employed as the work proceeds, until the cylin- der is reduced to the external dia- meter of the intended pipe, and lengthened in proportion. The man- dril prevents the internal diameter LEA 201 LEA from being reduced. The lead is hardened, compressed, and smoothed by the operation. As only 20 or 30 feet of length can be produced in this way, a hydrostatic pipe-press is used for making longer pieces. Melted lead is poured into a hydro- static press, where intense water pressure forces it upwards, com- pelling it to pass through a die which defines the external diameter, while a mandril defines the internal bore. Lead Shot. (See SHOT MANU- FACTURE.) Leather. This remarkable sub- stance still maintains its superiority over all others for a very large num- ber of purposes. Gutta percha in some cases, india-rubber in others, vegetable parchment in others, are occasionally substituted for it ; but for boots and shoes, for saddles and harness, for military equipments, for bookbinding, and for other ap- plications that might easily be named, leather eclipses them all. Leather, chemically speaking, is a substance quite distinct from the hide or skin of which it is made, being a compound of the gelatinous matter of the skin with a peculiar vegetable principle called tan, tan- nin, or tannic acid. In true leather the tannin becomes separated from the other parts of a vegetable solu- tion ; the dermis, or true skin, be- comes separated from the epidermis and the intervening tissue ; the tannin combines with the dermis, and true leather is produced. In practice, however, all sorts of skin and hide, treated in various ways, receive the name of leather, although differing very greatly in qualities. Every wild hunter in an African or Russian plain who dresses a strip of hide in any way to make a thong, virtually converts it into leather ; and some such modes have been known ever since there were hunters or animals to hunt. The skins and hides of ani- mals supply leather varying greatly in thickness and strength, to which different names are applied. Butts are the heaviest portions of ox-hides, and backs are nearly like them. Hides are either cow-hides or slight ox-hides. Stiff leather, in the mili- tary dress of the middle ages, was made of wild-bull hide, and was nearly pistol-proof and sword-proof. Four degrees of thickness are sup- plied by bull-hide, bullock-hide, cow-hide, and calf -hide or calf- skin : the first three of these are mostly employed for harness, and for the soles of boots and shoes ; while the fourth is used for upper leathers and for bookbinding. Sheep-skifi, is tanned into a cheap leather, which is used for an immense number of purposes. Lamb -skin., thinner and more delicate, has more special applications, Goat-skin, supplies a better kind of light leather than sheep. Kid-skin, provides the lea- ther for a large variety of gloves and ladies' boots. Deer-skin, is dressed with oil to make shamoy leather. Horse-hide makes good leather for horses' collars. Seal-skin is used for the same purpose, and for many others. Hog-skin supplies the lea- ther with which saddles are covered. Dog-skin, leather is made into gloves and other articles. Antelope, buf- falo, rhinoceros, hippopotamus, and many other sorts of hide are made into special kinds of leather, limited in application. There was a rough estimate, a few years ago, that the entire leather trade of the United Kingdom, including the leather-making and the manufac- tures subsequent to it, is worth ^14,000,000 a year. After sup- plying our own workers, we have a surplus of 40,000 or 50,000 cwt. an- nually for exportation. The more important manufacturing processes are described under TANNING; while subordinate matters are no- ticed under the headings named in the next article. LEA 202 LEV Leather Dressing: relates to the making of such leather as does not go through the long-continued pro- cess of tanning ; it also includes the currying or finishing of tanned leather. All the skins and thinner hides for conversion into leather require a preliminary removal of the hair, wool, grease, &c. ; how this is done is explained under FELL- MONGER. Many kinds of goat and sheep skin are made into morocco leather, either real or imitation, by tanning or dressing with the drug called sumach. Brought to the state of a clean pelt by the fell- monger, the skins are sewed up each into the form of a bag, with the grain side out, distended by blow- ing, and dyed by being steeped and worked about in a dye bath. They are then sumached ; that is, im- mersed in a warm solution of su- mach, which is made by pressure to force itself through the pores of the pelt. The bags are ripped open, and each pelt, spread out flat, is rinsed, drained, scraped, and rubbed. If required to be split into two layers or thicknesses, this is done by the splitting machine (noticed under TANNING). Sometimes the splitting is so cleverly managed as to produce three thin layers. Su- mached leather foi morocco requires much rubbing to give the peculi- arity of surface. Leather for some purposes is prepared with alum and e g by a process described under TAWING. The leather hides are tanned with oak bark, and then curried. (See CURRIER, CURRY- ING; TANNING.) W^z-rA-leather, prepared with oil, is noticed under SHAMOY LEATHER. Leather Substitutes. "We may give this name to many products which the inventors call leather doth, vegetable leather, imitation leather, panonia leather, &c. They nearly all consist of some composi- tion laid as a coating upon a woven cloth of flax, wool, or cotton, pene- trating more or less completely be- tween the fibres. The materials for the various compositions are very numerous linseed oil, lamp-black, turpentine, oak-bark infusion, alum, gelatine, stearine, resin oil, zopissa, solution of tin, india-rubber, leather parings, naphtha, gutta percha, &c. some or other of these combined in various proportions. The sim- pler of these leather substitutes are much used as a material for cheap bags, table covers, &c. Lemon Juice, Salt, Essence, &c. The juice of the lemon, extracted by heavy pressure, is the lemon juice which is found so valuable in the navy as an antiscorbutic. Slices of lemon, steeped in hot water, sweetened with sugar, and cooled, give the simple beverage lemonade. The effervescing drink under the same name is made from lemon juice and bicarbonate of potash, with sugar, &c. ' The oil or essence of lemons, sometimes also called scouring drops, is obtained from the rind of the fruit. Candied lemon- peel has its nature at once denoted by its name. Salt of lemons is a misnomer; it is a liquid contain- ing oxalic acid and potash, but no lemon. Lens Grinding 1 . Lenses for op- tical instruments are made of circu- lar pieces of flat glass, ground by means of convex or concave iron tools, with a grinding powder of sand or emery, after which the surfaces are polished with putty powder. The principle is much the same in all cases ; but wonderful care is needed in grinding and polishing the larger lenses for telescopes, and the exquisitely small lands for mi- croscopes. Level. To ascertain the horizon- tality of a surface or a line, the in- strument usually employed is a short horizontal glass tube contain- ing a bubble of air floating upon alcohol or water. The arrangement of the wood-work to which the tube LEV 203 LTG is attached may be varied in many ways; but it is usually such that when the bubble of air is exactly midway between the two ends of the tube, the instrument is exactly level, horizontal, or at right angles to the plumb-line. The levels used by bricklayers and other artisans mostly depend on the rectangular position of a plummet in regard to a horizontal straight-edge. Lever. The three main kinds of lever are illustrated in a vast number of instruments and imple- ments when in use. (i), where the fulcrum is between the power and the weight = common balance, scissors, pincers, &c. ; (2), where the weight is between the power and the fulcrum = oar, wheelbar- row, nut-crackers, many kinds of chaff-cutting and tobacco-shredding machines, c. ; and (3), where the power is between the fulcrum and the weight = fishing-rods, whips, um- brellas, tongs, &c., when not held quite at the end. It is instructive to notice, in any complicated ma- chine, in what infinite variety these three kinds of lever action are ren- dered available. Lewis, for raising heavy blocks of stone, is an old contrivance. It consists of three pieces of iron tem- porarily inserted in a cavity, so shaped that the stone can be raised by means of these pieces, and yet the pieces be easily taken out. Life Boat. A life-boat ought to possess these two qualities in a special degree a resistance to over- turning, and a readiness to right itself without sinking if overturned. When, towards the end of the last century, frequent wrecks on the east coast suggested the expediency of trying to save the crews of endan- gered vessels, various forms of boat were tried. The experiments of a long series of years resulted in the agreement upon the pattern life- boat which has been adopted by the National Life-boat Institution since about the year 1853. It has a water-tight deck between the bottom and the rowers' seats ; air- tight buoyancy chambers along each side, just above the deck ; a bottom nearly flat ; a mass of cork and light hard wood between the bottom and the deck ; a heavy iron keel to cor- rect the lightness of the superstruc- ture ; a bend upwards from the centre of the keel towards each end, to facilitate righting after an over- turn ; a covered receptacle to con- tain sails and tackle when out of use ; relieving tubes to convey away any water which may be shipped ; and a small hand-pump to expedite the clearing when necessary. This well-considered structure has enabled the noble institution which origin- ated it to save hundreds of lives. The life-boats are usually about 30 feet long and 8 feet broad ; they cost, with equipment, about ^400 each, and there is usually set aside another ^200 for a boat-house. Life-saving- Implements. Be- sides the life-boat, there are many contrivances in use for saving lives at sea. (1.) Life-mortars, ordinary military mortars, to fire off shot attached to a rope ; the shot being fired from the shore to a ship in distress, and the rope to assist the crew in getting ashore. (2.) Life-rockets, instead of shot, fired from rocket tubes instead of from mortars. (3.) Life-arrows, to be fired from an ordinary musket, car- rying a line or small rope. (4.) Life belts and jackets, made of cork, india-rubber, or some other buoyant material. (5.) Life buoys and rafts, to support a person on the water, but not to be worn by him as a garment. (6.) Life beds and t mat- tresses, to be floated on the water in times of exigency. In every one of these classes the variety of im- plements is very numerous, this hav- ing been a favourite subject for inventive ingenuity. Lighthouse Illumination. The LTG 204 LIG construction of lighthouses, the for- midable difficulties to be surmounted on lonely and storm-beaten rocks, are large subjects in civil engineer- ing ; but the progressive changes in the mode of lighting them may suitably be noticed here. At first, beacon fires were exhibited on ele- vated coasts to guide or warn the mariner, without any particular structure that could be called a lighthouse. This beacon was first a wood fire, then a coal fire. Next came the erection of some kind of tower, with a rude array of lamps or lanterns at or near the summit. Smea- ton's beautiful Eddystone Light- house exhibited merely tallow candles when first set to use in 1759; but these were afterwards superseded by oil lamps. When Argand (which see) improved the brilliancy of lamps by his new burner, this was employed; and when opticians pointed out how wonderfully a pa- rabolic reflector increases the vivid- ness of a light in a particular direc- tion by being placed behind it, this optical aid was added to the Ar- gand. When the Bell Rock Light- house was finished in 1811, its light apparatus was as follows : The lamps were to burn oil ; the frame in which they were fixed rotated slowly on a vertical axis ; some of the lights were white, and some red ; the white and the red alternated in coming to a particular spot, and arrived at maximum brightness after intervals of every few minutes. This admirable arrangement served to distinguish the Bell Rock clearly from all other lighthouses on the coast. A bell, worked by ma- chinery, tolled every half-minute in foggy weather. When the first cast-iron lighthouse was erected (1840) in Jamaica, the lighting ap- paratus consisted of fifteen Argand lamps, and as many reflectors, five on each side of an equilateral tri- angle, with a periodical flashing or alternation of brilliancy. The best brm that the catoptric or reflecting system presented was that of a lollow paraboloid of plaster, the concavity of which was stuck round with pieces of silvered plate glass ; :>ut in later years a better form was :hat of a large paraboloid of copper, brilliantly silvered on the interior, with an Argand burner carefully alaced in the focus. In some of ;he larger lighthouses the number of these distinct lamps and reflectors is very considerable. The dioptric ystem of lighting, with lenses in- stead of reflectors, is largely adopted. As a lens would be very large and costly for such a purpose if made in one single piece, an ingenious plan has been adopted of building it up piecemeal, each portion of glass having its proper curvature. Fresnel, Brewster, and Soleil intro- duced the system ; while Chance, Hartley, and Osier have in recent years greatly improved it. In the highest development of this plan there is one strong light in the centre, and a ring, or rather cylinder, of lenses all around it, every lens con- tributing towards the proper focal- isation of the light. The lime light and the electric light have both been tried as substitutes for Argand oil lamps. Experiments are still in progress on the subject ; and there is fair ground for expecting that the electric (or magneto-electric) light will eventually take a recognised position in the illumination of our larger lighthouses. It is also hoped that means will be found for illumi- nating by the magneto-electric light a beacon on a rock at some consider- able distance from the shore, an electric cable maintaining commu- nication between the shore and the beacon. Of the intensity of the electric light itself, as tried in light- houses, there can be no doubt. During the holding of the Paris Exhibition, in 1867, the electric light was displayed on a model tower of a lighthouse with marvel- LIG 205 LIM lous effect. " It shone night after night," said an observer, "large, steady, and lustrous as a planet ; and you could see in the darkness a beam passing as far as the eye could see. From the tower with the light at our back it was very marked, and quite lit the hills around Paris. The whole horizon in the plane of the light showed the white beam ; and at the distance of four miles it shone upon the windows of some houses, making them appear to be lit up." The Trinity House Cor- poration use the electric light at Dungeness Lighthouse, and propose to employ it likewise at South Fore- land and Lowestoft. Light-producing- Apparatus. "We may give this name to the various contrivances for producing light in tinder, wood, and other sub- stances, preparatory to lighting fires, candles, &c. Barbarous tribes all over the world know that light can be produced by rubbing two dry pieces of wood together ; the friction produces heat, and the heat fire. But this is too slow a process for persons whose time is valuable. The flint andsteel, so long in favour, but now so completely superseded, de- pended on the production of sparks of steel when struck off by a sharp flint, and the reception of them on tinder, which kindles into a kind of smothering fire sufficient to ig- nite a sulphur match. Phosphorus matches were small sticks of phos- phorus, which took fire on exposure to the air. Phosphorus bottles were small phials filled with prepared phosphorus, which ignited in con- tact with a sulphur match. The pyrophorus was a bottle containing a mixture of prepared flour, sugar, and alum, which ignited on exposure to the air. The instantaneous-light machine was an apparatus for ignit- ing hydrogen by the electric spark a scientific, but certainly not a household affair. The light-syringe was a kind of little pump, which made air hot enough by compression to ignite a bit of amadou or German tinder. The phosphorus box con- tained asbestos steeped in sulphuric acid : when a match was dipped into this box or bottle, tipped with a mixture of chlorate of potash and gum, it ignited. Phosphorus box was a misnomer, as there was no phos- phorus used. The eupyrion com- prised a little bottle or cell of sulphuric acid, which ignited matches tipped with sulphur and chlorate of potash. The Promethean consisted of an arrangement for bringing a drop of acid into contact with chlorate of potash : flame was pro- duced, which kindled a taper. All these ingenious contrivances gave way by degrees to the lucifer or congreve, in which the simple friction on a bit of sand-paper of a match tipped with a certain composition suffices to produce a light very quickly. (See MATCHES.) Lignite is imperfect coal : fossil wood which has not yet fully assumed the coaly texture. Lignum Vitse, the wood of the guaiacum tree, is one of the heaviest kinds known hard, close-textured, and useful for making ships' blocks, rulers, pestles, bowls, and many other articles. Lime. In so far as lime is applied to manufacturing purposes the carbonate is the most useful form ; but there are certain others worthy of note. Lime is itself an oxide, the oxide of calcium, a metal which is only known to the chemist. Lime, when pure, is nearly white, acrid, caustic, alkaline, difficult to fuse, gives forth a brilliant light when intensely heated, is slightly soluble in water, and slowly becomes con- verted into carbonate of lime when exposed to the atmosphere. Lime is called quick or unslaked in its pure state ; when water is added to it, it becomes slaked or hydrate, with a considerable change of properties. Cream of lime and time-wafer denote 206 LIN their own constitution. Chloride of lime forms the invaluable bleach- ing powder. Fluoride of lime is nearly the same thing as fluor-spar. Sulphate of lime presents itself in the forms of alabaster and gypsum, or plaster of Paris. Phosphate of lime, mostly obtained from bones, is of great value as a manure. Carbonate of lime appears in the various forms of Iceland spar, stalactites, stalag- mites, chalk, marble, limestone, &c. Under many of the above headings details will be found relating to the useful application of this important substance. Lime Kiln is a furnace for con- verting limestone into lime by se- parating from it certain constitu- ents which can only be removed by heat. The kiln may be an in- verted cone, a cylinder, a cube, but is more usually shaped internally something like a skittle, swelling out in the middle more than at the top or bottom. Many ruder forms of kiln are used, according to the kind of fuel available, and there are many modes of varying the process. The following are some of the arrange- ments of lime-burning in different parts of Europe : (i.) Alternate layers of coal or coke and limestone: 8 limestone to 2 coal or 3 coke. (2.) Fagots, then coal, theu lime- stone in small pieces, then coal again, and so on ; replacing at the top as fast as the calcined stone is removed at the bottom. (3.) Four parts turf and I part wood alter- nately with limestone. (4.) Lime- stone and peat alternating in kilns formed of peat. (5.) Furze to pro- duce a blazing heat, with large pieces of lime built up into a mass over it. (6.) A somewhat similar arrangement, with additional ap- pliances for burning bricks at the same time as calcining lime. Some kilns are emptied at certain intervals, and refilled, whereas others work continuously, being supplied t the top as fast as lime is drawn out at the bottom. As lime is, practically, limestone minus car- bonic acid, the details vary according as the kind of stone and the kind oi fuel facilitate the escape of that gas, Lime Ligrht. (See DRUMMOND LIGHT.) Limestone, as a material for building, is one of the two great classes of stone usually employed in this country, sandstone being the other. It comprises many different kinds- The oolites, or roestones, consist of little roe-shaped pieces cemented with calcareous matter. The shelly limestones are built up of minute shells, whole or broken, in a fossil state, with the calcareous cement. The magnesian limestones contain carbonate of magnesia as well as carbonate of lime, and bear a spe- cial relation to atmospheric action. There are other varieties known un- der various names, such as compact and crystalline limestones. Among the old buildings constructed of one or other of the different sorts of limestone may be mentioned St. Paul's Cathedral, the Norman portions of Southwell Church, the keep of Conisborough Castle, Tickhill Church, Roche Abbey, York Minster, Ryland Abbey, Sandesfoot Castle, Bow-and-Arrow Castle, Glastonbury Abbey, Wells and Salisbury Cathedrals, Merton College Chapel, the decorated parts of Spofforth Castle, Chepstow Castle, and Bristol Cathedral. Lime Tree, or Linden, produces a light, soft, tough, and durable wood, very suitable for carving. The natives of South Germany and the Tyrol produce a large quantity of carvings in this wood. The wood is also much used by turners, and makes excellent charcoal. Linen; Linen Manufactures. The word linen is derived from the Latin name of flax (linum) all kinds of linen being made of flax. The various manufacturing processes are treated under FLAX, and other LIN 207 LIT articles referred to under that head- ing. Belfast and the North of Ire- land take the lead in the manufacture of the finest linens ; Dundee and Aberdeen are the head-quarters for the coarser kinds of flax goods ; while Barnsley, in Yorkshire, takes an intermediate rank, producing an immense variety of middle-quality goods in flax. After all our home wants in this commodity were supplied, we were able, in 1867, to export 34,000,000 Ibs. of linen yarn, 3,000,000 Ibs. of linen thread, and 212,000,000 yards of woven linen or flaxen goods. Linseed; Linseed Oil. Linseed, grown to some extent in the United Kingdom, is still more largely im- ported from the Continent, chiefly lor pressing into Unseed oil and oil- cake. The continental growers also cultivate it for the sake of the flax. (See, on these subjects, FLAX, OIL, &c.) Liqueurs, nearly the same as English cordials, are some kind of spirit flavoured with various sub- stances. Absinthe, maraschino, ratafia, noyeau, cura<;oa, and kirsch- ivasser are examples. Cherries, bitter almonds, peach kernels, apricot kernels, peppermint, cassia, caraway, cloves, aniseed, &c., are among the flavouring agents. In sqme liqueurs the spirit is very weak; in others stronger. Litharge, the protoxide of lead, is prepared by heating the carbonate of that metal to dull redness, which brings about certain chemical changes. The substance produced is very heavy, of a delicate straw colour, and slightly soluble in water; it melts at a red heat, and then com- bines easily with silica. This last- named property renders it valuable in making flint glass, which becomes thereby heavy, brilliant, and highly refractive. It is also useful in form- ing salts with many of the acids. Litharge is sometimes called mas- sicot. Lithography ; Lithographic Stone. The very useful art of lithography was invented by Sene- felder, of Munich, towards the close of the last century. It consists in printing from stone, without any actual engraving. The Stones. The stone best fitted for lithography is a smooth compound of lime, clay, and silica ; it is found in various parts of Europe, but chiefly in Germany. It is easily quarried into slabs, and then into pieces for pictures of various sizes. They are ground level with sand, and are either grained on the surface by rubbing with powdered glass, or polished with pumice, according to the mode in which they are to be used. Different coloured stones, having varying degrees of hardness and smoothness, are available for different kinds of work. The Ink. Lithographers require two kinds of ink one for original drawings or writing; the other for transfers from other drawings or writings. The first kind of ink is made of white wax, shellac, hard soap, tallow, carbonate of soda, and lamp or ivory black. The second kind consists of printing varnish, tallow, brown noap, brown wax, shellac, black pitch, and lamp-black. There is also used a dry crayon, composed of Venice* turpentine, Brunswick black, mastic, tallow, white wax, hard soap, shel- lac, lard, carbonate of soda, and Paris black. The Processes. The artist writes or draws on the stone with a pen, brush, or crayon, accord- ing to circumstances. The ink or composition thus laid on is of such a character as to resist the action of acid. Weak aquafortis, mixed with gum arabic, is poured over the stone when the drawing is finished; and the unprotected stone is thereby slightly etched or eaten away, leaving the lines of the drawing a little raised. The stone will receive printing ink ; the greasy composition of the lines of LOG 208 LOG the drawing will not. This unequal action enables copies to be printed from the stone. Writings, plans, and drawings are quickly lithographed by the transfer process. The drawing is done on a prepared sheet of thin paper by means of pens and small hair pencils ; an impression is taken from the paper on a warmed stone ; the paper is removed by moistening and rubbing; and then the stone, after a few finishing processes, is ready to be printed from. By one method the lights of the original are represented by 'dark lines or spots in the impression ; by the other, every impression is an exact counterpart of the original. An immense ad- vance has been madein this art by the application of colour-printing and of steam presses to lithography ; by the imitation of chalk drawings and tinted drawings ; and by the transfer of photographs to the stone, thereby dispensing with drawing as well as with engraving. Lock, G-un. (See GUN LOCK.) Locks and Keys. The lock, in which so much ingenuity is em- ployed, exhibits many varieties in form, application, and designation. A bolt lock has a bolt which cannot be driven or withdrawn without the action of a key. A latch lock can be opened by a handle on the in- side, and by a key on the outside. Other designations are in-door, out-door, iron rim, spring, brass case, mortise, dead or closet, two- holt, knob or ring, right hand, left hand, one -ward, two ward, one wheel, two wheel, solid, cabinet, cupboard, bookcase, table, desk, drawer, box, caddy, chest, carpet bag, puzzle, padlock, and many others. In a plain lock of simple construction., the key, on entering the key-hole and being turned round, draws back the bolt, and opens the lock. If this were all, there would be no security, seeing that any blank key could open it. Therefore the interior of the lock is provided wilh wards, and the key with clefts corresponding to them : no key can pass among the wards unless it has the proper kinds of clefts or openings. The wards are made of small thin pieces of iron or brass, and vary greatly in numberand shape. The bit, or square portion of the key, varies in shape and thick- ness as well as in depth, to suit the wards of the lock. Most small keys are pipe keys, having a small barrel that fits upon a pin in the lock ; but street door keys are usually solid, and can open the lock both fro)ii within and without. Locks of a better kind have tumblers instead of wards : the tumblers are small movable or hinged pieces of metal within the lock, which must be first shifted or lifted a little out of their place before the key can act upon the bolt. The letter lock, puzzle lock, or comfa'nationlock^SiS usually a number of rings placed with their plane surfaces in contact ; every ring revolves on an axis ; and the lock cannot be opened until all the rings are brought into exactly-defined positions. The variety of puzzle locks is very great, and much ingenuity has been bestowed on this department of the art. For half a century the lock-makers and the lock-pickers have been engaged in a struggle to see which should vanquish the other*. Bramah, Barron, Chubb, Summerford, Price, Marr, Tann, Mordan, Newell, Par- nell, Hobbs, Denison, Cotterill, are a few only among the names oi those who have devoted themselves to the invention of locks which no one can pick. Those who remember the proceedings of the two Great Exhibitions in 1851 and 1862 will call to mind the excitement kept up between those who asserted and those who denied that certain locks were unpickable. Detector, prv tector, permutating, parantoptic, vibrating guard, compound lever, defiance, magnetic, duplex, detent, LOG 2OQ LOG holdfast, drill-proof, are among the names given by patentees to locks intended in one way or other to defy burglars. The manufacture of locks and keys forms a large and im- portant branch of industry in the Wolverhampton district, comprising that town, as well as Willenhall, Walsall, Wednesfield, and some others. The best locks are made at Wolverhampton ; but Willenhall is the great centre for the commoner kinds. In 1 866 there were 460 master lock-makers in the district, employ- ing 5,000 hands, and producing 32,000 dozens of locks every week. Locomotive, Railway. The first carriage that carried its own steam-engine, or the first steam- engine that propelled its own carriage, on a railway was at Merthyr Tydvil, in South Wales. Mr. Trevethick, in 1804, made such a locomotive to draw coal-trucks on a tramway. The cylinder was horizontal, and the piston-rod con- nected wit h another rod which moved the wheels. The little engine drew 10 tons at five miles an hour. An opinion arose that, with a large and heavy engine, the wheels would not bite the rails sufficiently to insure progression ; hence a multitude of plans to get over this difficulty cogged wheels, racked or toothed rails, chains and grooved wheels, propellers likehorses' legs, additional wheels for additional friction, were tried ; but the two Stephensons at length proved that the locomotive will bite the rails sufficiently, without any of these aids, on a moderate level ; while later improvements have enabled it to surmount con- siderable inclines. The Rocket, the locomotive with which Robert Stephenson won the prize in 1829, on the Liverpool and Manchester Railway, settled this as well as many other disputed points. Few machines have been subjected to a greater number and variety of im- provements than the locomotive between 1829 and 1868. The kind of fuel, the shape of furnace, the mode of feeding, the number and arrangement of hot-air flues, the avoidance of smoke, the escape of gases, the supply of steam, the valve arrangements, the cylinders and their pistons, the cranks and rods, the driving- wheels allhave engaged the closest attention of engineers ; and the patents on these subjects alone form a formidable list. The locomotives now employed for the Limited Irish Mail Trains, be- tween Euston Square and Holy- head, show the perfection which has been reached. In one of them (which may be taken as a type) the fire-box has 15 square feet of fire- grate, to give out heat as rapidly as possible. The boiler, io feet long, has 192 hot-air tubes, about 2 inches diameter. There are two outside cylinders, 16 inches diameter, 24 inches stroke, with a steam-pipe and a blast-pipe about 4 inches diameter. The driving-wheels are 7^ feet diameter. The heating surface of the tubes and fire-box together is not less than 1 , 100 square feet. The apparatus for feeding with coal is so arranged as to prevent smoke almost completely. The engine is supplied with water -while running by a most ingenious in- vention ; the tank scooping up water from a trough placed between the rails. The water, as fast as needed, is transferred from the tank to the boiler by Giffard's injector. (See INJECTOR.) The mechanism for economically consuming the coal, for lubricating all the moving parts, for reversing the motion, &c., is of the highest class of efficiency. The engine weighs, in working order, 27 tons, and the tender 17 tons ; the tender holding 2 tons of coke and 1,500 gallons of water. Such a locomotive (worth not much less than ^"3,000) has been known to run 130 miles in 144 minutes without stopping, scooping up its own supply LOG LOG of water on the way. Some of the new locomotives by Fairlie, Corliss, England, and other makers embody varied and important improvements. It is a grave matter for English ma- chinists to consider, that their con- tinental rivals are gradually advanc- ing in the manufacture of locomo- tives, which they used to buy in England. Foreign machines are now even imported into this country. In 1867 no less than forty locomotives were under process of manufacture at Creuzot, in France, for our Great Eastern Railway Company ; and twenty, for some of our Indian rail- ways, at Esslingen, in Wurtem- burg. Locomotive, Road. Very little success has hitherto attended the endeavours to draw carriages along common roads by steam power. That it can be done, of course, re- quires no proof; but the commer- cial success is doubtful. James Watt and Dr. Robison both enter- tained the idea. Mr. Murdoch, a Cornish engineer, appears to have been the first to realise the project, about 1786, by running a little loco- motive on the highway near Red- ruth. William Symington, of Edin- burgh, constructed a model on a dif- ferent principle ; and so did Oliver Evans, of Pennsylvania. Messrs. Trevethick and Vivian ran a road locomotive, in 1802, on a trial bit of ground exactly at the spot where Euston Station now stands. The badness of the turnpike roads, and the opposition of turnpike trustees, prevented the realisation of hopes in regard to these plans. Many years elapsed; and then began a new series of endeavours, in which Griffiths, Brunei, Gordon, Golds- worthy Gurney, James, Hancock, Burstal, Summers, Ogle, Heaton, Church, Macerone, Dance, Field, Hill, Anderson, and others in turn took part. Some of the steam car- riages or road locomotives con- structed by them plied for traffic in a regular way between Gloucester and Cheltenham, between Oxford and Birmingham, between London and Stratford, between Glasgow and Paisley, and on other routes; but none of them paid sufficiently, and all were in turn abandoned. One of the most recent road locomotives was constructed for the Earl of Caithness in 1861. It was a kind of hooded chaise, with a small locomotive be- hind it, carrying water enough for fifteen miles, and coals for thirty ; the driver, sitting on the front seat, could turn the steam on and off, and work the rudder-wheel and the brake ; an assistant, on a small platform at the rear, attended to the fire. The whole affair, with four persons, weighed i tons. The earl drove this carriage through the Highlands, from Inverness to near John o' Groats, with his coun- tess and two gentlemen as pas- sengers. The distance (150 miles) was the greatest ever achieved on a common road by a locomotive. Still, the steam carriage was re- garded only as a curiosity, so far as passenger conveyance is concerned, and so it has ever since remained. More success has attended traction engines for slow heavy traffic. Tay- lor, Bray, and other inventors have contrived such engines, which are found very useful in the transport of great weights on ordinary roads. In these engines the wheels are very broad, and are made with some con- trivance for biting the road well. Log- is an instrument for mea- suring the speed of a ship through the water. In its simplest form a float is thrown out into the sea, with a line or cord attached to it : the length of line drawn out in a given space of time measures roughly the speed of the vessel. In a more accurate arrangement, Mas- sey>s patent log, there is a kind of clockwork which measures the dis- tance : the number of revolutions of a vane may be read off on a self- LOG LOO registering dial, and compared with the time elapsed, from which the ship's velocity maybe deduced. In Walker's log the rotator is attached immediately to the registering part of the machine, to economise space, and to prevent fouling of the line. There is also an ingenious machine for registering long or short dis- tances at sea. A log is fixed to the after part of the keel, and commu- nicates by an air-tube with an index placed in the cabins above. Messrs. Siemens and Halske have applied their scientific skill to the construc- tion of an electric log : an insulated wire leads from the ship to a train of wheel-work contained in an air- tight case, and driven by the vane of the log ; the electric action is connected with the wheel-work. Logrwood, the heart-wood of a Mexican tree, is not much used as timber, but is one of the most useful of dye-woods, yielding a very red infusion when boiled in water. As it is imported in billets or logs of some considerable size, there needs a log-wood mill to cut it up into strips and fragments. According to the substances used with it, log- wood may be made instrumental in dyeing bright and dark red, purple, violet, lilac, and even black ; and thus it is highly valued by the dyer. It shows how large must be the con- sumption of this dye-stuff, that no less than 570,000 cwt. of logwood was imported in 1867. Looking Glass. (See PLATE GLASS ; SILVERING ; SPECULUM.) Loom, Hand. The loom for ordinary weaving is a very ancient apparatus. In the oldest Egyptian pictures and sculptures the principle of its action is discernible, however imperfect the mode of application. In the simplest weaving, the -warp or long threads are crossed at right angles by the weft or short threads, each weft going over and under the warps alternately. To effect this, the warp threads are stretched out side by side, the distance between them depending on the fineness or coarseness of the fabric, and their number on the width of the cloth to be woven ; they pass over the yarn beam at one end of the loom, and over the cloth beam at the other; and as one of these beams gives it off, the other takes it on. Each warp thread passes through a loop or eye in a vertical string ; half of these strings are connected together by cross-bars at top and bottom to form a heald, the other half to form another heald ; and two ad- joining threads of warp always be- long to different healds. The threads also pass through dents or teeth in a reed, which reed is set in a movable swing frame called the batten. Now the action is this: The weaver, sitting at the cloth-beam end of the loom, presses down a treadle, which draws down one heald and raises the other; half of the warp threads are thereby lifted up a little way, the other half (alter- nately with them) pulled down a little way. There is thus formed an opening or channel across the whole width of the web ; and through this channel, called the shed, the weaver throws his shuttle (see SHUTTLE), say, from right to left. One thread of weft is thus driven across the warp. By a smart blow with his batten (which swings easily) he drives up this thread close. Then, putting his other foot on another treadle, he reverses the two healds, and forms a new shed, through which he throws the shuttle from left to right ; and so on, one weft thread after another. There are many subsidiary pieces of appa- ratus, but the principle is always the same. Loom, Machine. So long as the fabric is plain, like calico or linen, the hand-loom will suffice to weave it ; but if it is figured an ad- ditional apparatus is necessary. In LOO 212 LUT this case, the warp threads, instead of being raised alternately, are raised two or more together, then one only, then two or more, ac- cording to the exigencies of the pattern. Hence two healds will not suffice ; there must be other me- chanism for raising the warp threads in some prescribed order. A draw- boy was at one time employed for this purpose. Many healds, de- pending in number on the pattern, were so arranged that a boy, by pulling at certain strings, could raise any heald or group of warp threads. But as the excellence of the work depended on the right group being pulled up at the right time, and as a boy could not always be relied upon here, an improve- ment called the draw-loom was de- vised, which insured something like mechanical precision in this work. A more effective and beautiful sub- stitute for the draw-loom is de- scribed under JACQUARD MACHINE. The power-loom, or. weaving-loom worked by steam power, of which Dr. Cartwright was the chiei in- ventor, has the warp threads hori- zontal, and wound round a warp- beam at one end and a cloth-beam at the other; there are also two vertical healds (for plain weaving), a batten with its reed of dents to drive up the weft thread, and a shuttle-race along which the shuttle travels. All the essential parts are there in principle, as in the hand- loom ; the important difference is that the various movements are effected by steam power, instead of by the hands and feet of the weaver. The raising of the healds to form the shed in the warp ; the throwing of the shuttle ; the driving up of the weft with the batten ; the un- winding from the warp-beam; the winding of the cloth-beam all are here the work of steam. There is also a beautiful contrivance for stopping the loom whenever any of the threads break. So completely is the work done by steam, that one girl is able to attend two looms, to perform such minor duties as sup- plying the shuttles with fresh cops of weft, &c. A power-loom for weaving fabrics of extra width, with a Jacquard machine over it to pro- duce figured patterns, form together a very triumph of modern ingenuity. For Bonelli's Electric Loom see JAC- QUARD MACHINE. Lucifer Match. (SeeMATCHES.) Lustre Ware is a kind of stone- ware which presents a very gay ap- pearance, in virtue of certain pro- cesses which it undergoes. The ware itself is carefully made and baked, almost as much so as porce- lain ; and the lustre is produced by means of metallic oxides. Thus platinum will produce a lustre like that of polished steel; while gold and silver will produce lustres like those of the two precious metals. The metals are prepared and ground into a kind of paint, which is ap- plied to the ware by means of camel-hair brushes. The heat of an oven brings out the lustre with the proper tint and brilliancy. Sil- ver and platinum lustres succeed best on white ware, gold on co- loured ware. Iron and copper lus- tres can also be produced. A beau- tiful iridescent lustre results from the use of chloride of silver, com- bined in a peculiar way with other substances. The kind of ware to which lustre is applied is made of a mixture of clay, flint, china stone, and felspar; and a peculiar glaze interposes between it and the lustre. Lute is a cement for mending fractures, or for temporarily closing vessels, apertures, &c. It may be composed of pipe-clay, loam, linseed meal, iron filings, slaked lime, borax, resin, wax, white of egg, turpentine, white-lead, india-rubber, &c., according to the land of article to be luted. A serviceable lute for glass and earthenware is made of linseed meal, worked up with water LUT 213 MAC into a soft, plastic dough ; it be- comes stronger if a little milk or lime-water is added. A cement or lute for mending broken porcelain or earthenware may be made by kneading up a strong solution of glue with new-slaked lime, and adding some white of egg. Lye, Ley, or Lees, is a solution of alkaline salts, resulting from va- rious manufacturing processes, espe- cially Soap Manufacture (which see). M. Macadamised Roads. Mr. Macadam's theory of a road ma- terial was, not fragments of stone of any size and all sixes, but fragments as nearly one particular size as pos- sible. Many machines have been contrived for crushing granite for this kind of use. In Messrs. Ellis and Everard's stone-crushing mill a strong feeding-apron, made of iron links and bars, and having a continuous action around two wheels, carries fragments of granite to a spot where they are tilted over into a hopper. The fragments come under the action of two chilled iron rollers, which break them to a cer- tain degree, and then between two others, which further reduce them to one uniform size. The rolls are fluted in a peculiar way, and are adjusted to any required interval apart. The stones pass into a re- volving riddle, which separates those which are the proper size from others which, being too large, are raised by an elevator and crushed a second time. The rolls weigh about 10 cwt. each, and will crush about 1, 800 tons of granite before requir- ing to be re-cast. The cost of break- ing granite is said to be reduced from 2s. 6d. per ton by hand to lod. by machine. Neal's stone- grinding mill is adapted for a dif- lerent purpose that of grinding stone to actual powder for various uses. The relation which Macadam's plan bears to others is briefly noticed under ROADS. Macaroni is a pipe or rod of wheaten dough. The Italians make it in immense quantities. The dour selected for it is always of a superior kind, the grinding is carefully con- ducted, and the dough is made very smooth and tough, with about 24lbs. of soft water to 100 Ibs. of flour. When in thick rods it constitutes macaroni; when thinner, -vermi- celli; both being shaped by forcing the dough through dies or gauges, as in wire-drawing. The dough is also stamped out into small ornamental pieces. Mace. (See NUTMEG.) Machine Tools. Nothing is more striking in the manufacturing activity of the present day than the substitution of machine tools for hand tools wherever it can be done. The machine tools are practically the makers of all machines, whether for spinning cotton, rolling iron, developing steam prime-movers, making paper, boring cannon, weav- ing lace, stamping buttons, drawing wire, or anything else. The Whit- worths and other great firms of the North must provide the machine tools before the steam-engine builders, locomotive makers, and machinists generally can set to work. What the machine tools really effect is, to give shape to pieces of metal and wood, leaving workmen afterwards to put those pieces together, and make them up into engines, ma- chines, and apparatus of various kinds. They are worked by steam power, with as little call as possible for manual labour. Some of our great establishments will employ 3,000 to 4,000 hands in this very craft. Of the great variety of machine tools the following are the principal : MAC 214 MAC (I.) The Turning Machine. The self acting lathe, with the slide rest, is one of the most useful of all ma- chines, as it gives cylindrical and spherical forms in a way which no other mode could equal. The cut- ting tool is held in a sort of vice, which is made to travel along by the slide rest ; this longitudinal mo- tion, combined with a rotary mo- tion of the piece of metal or wood to be turned, brings every part of the surface under operation. Modi- fication of the details leads to the production either of smooth sur- faces or of varied ornamental spiral grooves, &c. Some of these machines are now so gigantic that they will turn a shaft, or other mass of metal, 50 tons weight, or 50 feet in length. (2.) The Planing Machine, for pro- ducing plane surfaces, has led to an immense saving of steam power, by lessening the friction between flat surfaces of metal which have to move in contact. Instead of making the cutting tool travel along the work, the latter usually travels along under the cutting tool in the planing machine : the bed or table on which the work is fixed has a reciprocating horizontal movement, in which the work shares. The cutting tool makes a large number of minute cuts strictly parallel not a broad shaving, like the carpenter's plane. Some of tht planing machines now made will give trueness of surface to a slab or plate of metal 40 feet by 12. (3.) T\\Q Slotting Machine cuts out peculiarly-shaped bits of metal from the work, to produce holes of special size and shape. Numerous slotting tools are provided, any one of which can easily be adjusted to the machine. Itisalso used to give some- thing like a rough contour to a piece of cast metal, and thereby economise labour with the turning and planing machines. One of these machines has been able literally to chop up into bits a mass of steel a yard in thickness ! (4.) The Vertical Drill- ing Machine has a vertical rod, to the lower end of which a drilling or boring tool can easily be fixed ; the tool revolves very rapidly, and soon worms its way into any piece of metal placed beneath it. (5.) The Radial Drilling Machine differs from the vertical in having the tool affixed to a radial arm, which is movable. Range of operation in different di- rections is hereby obtained. (6.) The Shaping Machined used where the lathe is not applicable, for pro- ducing an almost infinite variety of curved and flat surfaces, such as we see in levers, rods, cranks, &c. Sometimes the tool travels along over the work, sometimes the work travels under the tool. (7.) The Punching Machine. This makes holes of various sizes in plates and slabs of different thicknesses. It does not simply drill a hole by wear- ing away the metal to fragments, but punches a piece of metal clean out. This is done by the pressure of a cylindrical tool ; and the pres- sure is so intense that a piece of cold iron an inch or more in thickness is punched out with as much facility and quickness as if it were a piece of cheese. (8.) The Shearing Ma- chine cuts off strips of metal of any length and thickness. The plate or slab is pushed on so as to meet each cutting stroke of the ponderous shears, the upper blade of which works down upon the lower with a force almost irresistible. By the esta- blishment of a double action one ma- chine will sometimes punch at one end and shear at the other. (9.) The SteamHammer. This marvellous aid to the engineer is described sepa- rately. (See STEAM HAMMER.) There are many other machine tools pro- vided with automatic action ; but the above are the principal. One of these, invented by Mr. Whitworth the great master in this art is so exquisite in construction, that it will measure a difference so small as one- millionth of an inch in the thick- MAC 215 MAC ness of two pieces of steel ! By another contrivance he rubs two surfaces of iron or steel over each other in such a way as to produce a flatness or level of surface more ab- solute than had ever before been produced a work of great value in the slide-valves of steam-engines and other machines where this kind of equability of plane is essential. Mr. Whitworth also introduced a system of standard gauges to regu- late the thicknesses of sheets, wire, and screw threads. Machine Working. The Jury of the International Exhibition of 1862, on this department of indus- try, made the following judicious remarks on the advantages accruing from the use of machine tools. The substitution of such for hand tools " is beneficial to workmen because it turns to the best account their natural forces, employing the physical power of water in motion, or of the genera- tion of steam, to overcome material resistances, and thus renders free and useful the higher faculties of man, which are crippled when his muscles are taxed to the utmost just as we see an animal running very fast unable to perform any useful dynamical work. There is no person who witnesses the pro- ceedings of an engineer's shop that does not appreciate the beneficent change wrought in the condition of the workman by machine tools, which spare him manual exertions, and do the hardest work in a uni- form and steady manner, while he is enabled to guide them by small levers, minding more than one at a time." In the next place, as to the effect of the use of machine tools upon the work done : * ' When an operative, who devoted all his care to do his work in the best manner, had acquired great skill in using his hand tools, nothing more was left for him to improve. He continued to repeat again and again the same process, never sure to obtain, even with the same careful attention, an exactly equal result. But now, when a machine tool is made to perform a certain work, to repeat it identically as long as it is required, and with that beauty of form and finish which is the prevailing feature of modern mechanical industry, nothing pre- vents the genius of a mechanic from devising a new arrangement of the working parts, of the mechanism, or of the framing, which may greatly improve its action, and enable it to do better and cheaper work in less time, and with simpler con- trivances." When we find that the machinery exported from the United Kingdom in 1867, irrespectively of steam-engines, was valued at ^3,000,000, after supplying home demand, we shall have some idea of the amount of work which machine tools now execute. Machine Workshops. The ma- chine makers, machinists, mecha- nical engineers, or whatever we may call them, make the machine tools ; but they employ similar machines to make them with; and similar machines are afterwards used both to make and to repair the countless engines and machines employed in manufacturing operations. An en- gineering workshop, therefore, is in our days a development of the same principles, and an applying of the same agencies, whether in the gigan- tic establishment of Sir John Brown at Sheffield, or in the workshop at- tached to a factory. In many large engineering and mechanical esta- blishments, irrespectively of those in which the machine tools are actu- ally made, there would be an im- portant saving of cost if machines could be repaired, and defective parts replaced, on the spot. The saving of time, of money, and of freight would be enormous. This is particularly the case where steam- vessels are stationed, and where there are some repairs or other of machinery needed after every long MAC 216 MAG voyage. The great Steam Naviga- tion Companies have such engineer- ing depots of their own; and almost every large mill or factory has some- thing of the kind. It is felt that if f,uch places were established more abundantly than they are in India and the colonies, great industrial advantages would accrue. In many places, too, there would be almost as much advantage in having a foundry for melting scrap and other iron, and a smithy for working up the metal at a red heat. Some of the grandest establishments of this kind are the engineering depots of the great railway companies such, for in- stance, as that which belongs to the London and North Western Com- pany at Crewe. According as the works comprise some or all of these departments (i), building locomo- tives; (2), repairing locomotives; (3), building carriages ; (4), repairing car- riages so will the arrangements be of less or greater magnitude. At Crewe seventeen acres of land are i covered with workshops, smithies, foundries, and mills, filled not only with machine tools such as have just been described, but engines and machines of other kinds and vast power. Bessemer steel-works, rolling-mills for rails, tilt-hammer forges, furnaces of all sorts and sizes, forges for making axles and wheels, single and duplex steam hammers, travelling and steam cranes all are here, and all on a scale of vast magnitude. Mr. Cola gives some useful estimates for a complete set of machine tools and other working apparatus adequate for the repair and partial renewal of machinery on a considerable scale. He sets down the following figures for three component departments* of such an establishment : Foundry : about ^1,000 for a cupola furnace, blast fan, foundry patterns, sand- grinding mill, travelling crane, with ladles, lifting chains, &c. Smithy : about ,1,500 for six smiths' hearths, blowing fan, plate-bending machine, punching and shearing machine, steam hammer, grindstone, six set.-, of smiths' tools, boiler-makers' tools, anvils, blocks, &c. Engnieers" 1 Shop: about ^"3,700 for slide and screw-cutting lathes with different lengths of bed, three hand-turning lathes, two planing machines, two vertical drilling-machines, two radial drilling machines, two shaping ma- chines, two slotting machines, ver- tical drilling and boring machine, screwing machine, two grindstones with frames, sets of drills and steel tools, chipping hammers, gauges, c. Together with about ^2,300 for steam-engine, boiler, and mill gearing; or 8, 500 in all. This is the plant suitable where steam - vessels are to be repaired, or where large factories and mills have to be attended to. Steam-engines, boilers, and machines of moderate size could even be made at such a place. A me- chanics' shop attached to a factory might be supplied with a good plant of machine tools from^"8oo upwards ; and it is found better in the end to have a small steam-engine to drive these machines, separate from the larger one employed in the factory itself. Madder is one of the most useful of all dyes, exemplified in the fact that in 1867 we imported no less than 260,000 cwt. of it. The roots, of the madder plant are taken up, dried in stoves, threshed to remove the loose skin, ground under vertical stones, and the meal sifted to dif- ferent degrees of fineness. Madder is used by dyers to produce an al- most infinite variety of red tints, and others called madder purple, madder orange^ madder yellow, &c. Mag-azine. (See GUNPOWDER.) The Government magazine at Pur- fleet contains 52,000 barrels of powder, and that at March wood ' 76,000 barrels. Magenta. (See ANILINE CO- LOURS.) The reader will, perhaps, MAG 21' MAG remember the magnificent crown of magenta displayed by Mr. Nichol- son at the International Exhibition of 1862. Magic Lantern. (See CAMERA OBSCURA.) Mag-istery, like regulus and many other terms now disused, was a name given by the alchemists to certain forms or states of metals. A magistery was a white powdery substance precipitated during the making of certain metallic solu- tions. Mag-nesia, as an earthy sub- stance, was known long before the metal magnesium, of which it is an oxide. The name is popularly given to the carbonate of magnesia, but ought, in correctness, to be con- fined to the caustic oxide. Caustic magnesia, the true oxide, is easily obtained from the carbonate. It is a white insipid powder, almost in- soluble in water. Its value in medicine and the arts is not very extensive. Carbonate of magnesia forms the whole of one particular mineral, and portions of many others, such as dolomite and mag- nesian limestone ; these are useful in making cements. The carbonate is obtained from this limestone by the action of heat and various che- mical agents. There is also a mode of obtaining it from bittern (an oily liquor formed during the prepara- tion of common salt). One mode of preparing the carbonate brings it to the form of soluble magnesia. A combination of the carbonate with the hydrate produces the mag- nesia alba of the chemists, one form of which is called heavy and another light. Magnesian Limestone. (See LIMESTONE.) Magnesium is one of the many metals which are more useful in the arts in a compound than a native state. When pure, it is white, silvery, slightly ductile, and de- composes water rapidly at 212 Fahr. The best known of its properties when in a metallic state is the intense light which it gives out when heated. (See MAGNESIUM LIGHT.) To a certain limited extent the metal may be drawn into wire, flattened, bored, and filed. The oxide of magnesium is Magnesia (which see). Of the salts formed from it, the carbonate is the well- known medicine (noticed in the same article). For the sulphate see EPSOM SALT. The phosphate is a valuable constituent in fertile soils, and is found in the husk of grain, in potato, and in many other plants. The silicate is described under MEERSCHAUM PIPES. Among the mineral substances containing more or less magnesium are soapstone, talc, asbestos, chrysolite, and bitter- spar. Magnesium Light. So long as the metal magnesium was very costly (which was the case until 1863), it could not be much used in the arts ; but when Deville, Caron, and Sonstadt invented new modes of obtaining it, it became available. Magnesium is now extracted from magnesia by a complicated series of chemical actions and reactions. The relation of this metal to light is something wonderful. At its melting temperature it takes fire, and burns with a dazzling, brilliant, bluish-white light ; this light is so steady and equable as to be service- able as a photometric standard, while its chemical properties render it very valuable in photography by artificial light. In illuminations and fireworks the magnesium light now takes part ; the intensity is such that a bit of magnesium wire, T^oth of an inch thick, gives forth as much light as seventy-four stearine candles of five to the pound. About I yard of wire would be burnt away in one minute; and at this rate it is calculated that 2\ ozs. mag- nesium would give as much total light as 20 Ibs. stearine. Magnesium MAG 218 MAL lamps are now made, in which the wire, uncoiling from a spindle by means of clockwork, is guided through a slit till it comes into contact with a gas or spirit flame. Another form has a supply of powdered magnesium mixed with fine sand ; a continuous stream of the mixed powder falls upon the flame, and maintains a steady, brilliant light. The usefulness of the magnesium light will mainly depend on the degree to which the metal can be still further cheapened. Magneto-electric Machine. At present the magneto-electric machine is mainly in the hands of experi- mental men of science ; but there is reason to hope that it will gradu- ally find its way into workshops, or at least into large engineer- ing operations. Its action depends upon a rather abstruse development of rotative power by the mutual in- fluence of magnetism and galva- nism. As a source of power, of light, of heat, and of telegraphic action, the machine is likely to have an important future. It produces a current more available for many purposes than the galvanic battery. Recent forms of magneto-electric machines by Mr. Wilde and Mr. Ladd are attracting much attention from practical men. Mahogany. This favourite wood is obtained from one of the largest kinds of tree growing in Central America and the West Indies. The trees are cut down, and the trunks squared into logs, in immense number. Mahogany is occasionally used solid, but much more frequently as a veneer to a cheaper wood. If the grain is fine, a high price will be given for a log, to be used as veneer. Messrs. Broadwood once gave ^3,000 for three logs of mahogany taken from one tree ; each log was about 15 feet long, 3 wide, and 3 thick; and was cut into veneers of eight to an inch for pianoforte work. 53,000 tons of mahogany were im- ported into the United Kingdom in 1867. Majolica Ware. This name is given to a peculiar kind of fine pot- tery (not porcelain) which was first made at Pesaro, in Italy, about four hundred years ago, and of which the manufacture was continued with some energy for two centuries. It is supposed that Raffaelle, and it is well known that other eminent painters, prepared designs for the chief articles made; this gave an artistic tone to the manufacture. The name Raffaelle ware is, in fact, sometimes given to majolica. One of the celebrated potters of that part of Italy, Delia Robbia, invented a beautifully white, durable, enamel glaze. Another, Giorgio, succeeded in finding such combinations of mineral colours as enabled him to produce ruby and golden tints with a peculiar iridescent lustre. Such specimens of Giorgio's majolica as still exist command enormous prices. Another great improver of this ware was Fontana, just about three centuries ago. After his time the excellence of the production fell away, and soon afterwards the manu- facture ceased at the place of its birth. The name majolica is a corruption from Majorca, into which island the Moors introduced the manufacture of a peculiar ware very brilliantly decorated in colours. Considering majolica ware to be, not in any sense porcelain, but a thickly and opaquely enamelled clay, suitable for receiving brilliantly- painted devices, the Staffordshire potters resolved a few years ago to revive the art of producing it, and they succeeded. We have now, consequently, English majolica slabs, friezes, tablets, vases, flower- pots, &c. Malachite, a green carbonate of copper, is a very beautiful mineral, which, when cut into thin layers, can be used as a kind of veneer for costly articles. The Russians are MAL 219 MAN very skilful in working it, as was shown at the two Great Exhibitions in 1851 and 1862. The working is very difficult. The pieces are first sawn into thin plates by means of vertical circular saws, fine sand and water being constantly supplied to aid the process. The portions intended for curved surfaces are cut by bent saws fitted to the required shape a task requiring much more care than the cutting of flat veneers. Then comes the joining, or junction of many pieces into one flat surface ; this is a slow and delicate process, seeing that the markings in any one piece are made to harmonise with those in the adjoining pieces, to produce a kind of pattern. The malachite veneers are applied to iron, copper, marble, or stone ; when cemented down, any minute deficiencies in them are filled up, and the whole beautifully polished. Malt and Malting. Malt is barley which has undergone a pecu- liar process. It is made to germinate by heat ; the starch is converted into sugar ; and beer or ale can be made from the extract more effectively than from unmalted grain. Wheat, oats, rice, rye, maize, may all be malted ; but barley is the most suit- able. Steeping. The first process in a malt-house is to steep the barley. This is done in a stone cistern, the water remaining on the barley two or three days or more. The grain imbibes moisture and swells; car- bonic acid is given off ; some of the husk or skin dissolves ; and the grain becomes softer and whiter. Accord- ing to the quality of the barley the weight increases by steeping, as little sometimes as 10 per cent., as much in other instances as 80 per cent. Couching. Removed from the cistern, the steeped barley is thrown on the floor of the malt-house in a heap called the couch, where it re- mains a considerable time. It under- goes a sweating process. It gives off moisture, increases in temperature, feels warm and moist to the hand, exhales an odour like that of apples, and begins to germinate at the ex- tremity of each grain. Flooring. At a certain stage in the sweating the couch is shovelled down, the grain spread in a thinner layer on the floor, and frequently turned. It absorbs oxygen, gives off carbonic acid, increases in warmth, and an evident change takes place in the meal or starch within the husk. Kiln Drying. At last the malt reaches the kiln, which is a room kept heated by hot air ascending through holes in the floor from a furnace below. The malt is spread over the floor, and is gradually raised to a temperature of 120 or 140 Fahr. It is chiefly on the manage- ment of this process that depends the classification of malt into pale, amber, and brown. loo Ibs. of un- dried barley produce about 80 Ibs. of malt ; but the malt occupies more space than the barley, in the ratio of about 108 measures to 100. The whole substance of the grain is mellow, and the taste is sweet. In this condition the barley is best fitted to yield its saccharine extract for making malt liquors, whiskey, vine- gar, &c. (See BREWING; DIS- TILLING ; VINEGAR.) The residue from the malt-house, under the names of malt refuse, dust, corn- ings, waste, and draft, is useful for feeding cattle and for manure. About 50,000,000 bushels of malt came into the official accounts of the Excise in 1867. Maltha is one of the names for mineral pitch, which is probably petroleum reduced to some degree of solidification. Being soluble in naphtha and oil of turpentine, mal- tha becomes useful in many of the arts. Manganese is a metal the chief usefulness of which in the arts de- pends on the properties of its oxides. When pure, manganese is grey-' tinted, moderately ductile, can be MAN MAN filed, but not hammered, and is about eight times the density of water; it has an intense affinity for oxygen, and decomposes water at 2l2Fahr. It is isolated with great difficulty, by laboratory processes, from some of the oxides. The protoxide of this metal is a dingy green powder, and is the basis of most of the manga- nese salts. The sesquioxide is a blackish -brown powder that gives a violet tinge to glass. The peroxide, or black oxide, is the most prevalent ore of manganese ; in various forms of preparation it is used in pro- ducing oxygen gas, in making bleaching powder, and in giving a black colour to earthenware. The sulphate is used in dyeing and calico-printing for the colour called manganese brown. There are many other combinations of the metal ; but these are the principal which have been usefully applied in the arts. Mangle. The mangle used for do- mestic linens and calicoes is a species of calendering machine (see CA- :LENDERING), to givesmoothness and gloss to woven goods. The common mangle contains a large wooden box or chest, rilled with stones to make it heavy. The chest rests on two hard wooden rollers, which rotate whenever the chest moves to and fro in its frame ; and this motion is communicated by a kind of windlass and handle, the handle being moved opposite ways during the return mo- tion of the chest. Baker's patent mangle has a frame and chest of cast-iron, a fly-wheel to ease the working and equalise the power, cogs and pinions to communicate the motion, a rack and pinion to reciprocate the motion in both di- rections, and a balance to facilitate this action. Manna is a juice which exudes from the stem of a kind of ash tree. When incisions are made in the stem, a saccharine juice slowly exudes, which hardens into yellowish lumps or flakes like hard honey. Manures, considered in their manufacturing relations, have now become a large and important item in our national industry, irrespectively of any scientific theories as to their relative usefulness in agriculture. Cattle-dung and farm-yard refuse are the natural manures first applied to use ; but the manufacture of arti- ficial manures is every year assuming proportions of greater and greater magnitude. Beginning with the pre- sent century, there have been the following among many compositions proposed, and more or less brought into use : Pounded ovster-shells and gypsum ; night-soil, calcined river mud, and any soil or sediment containing carbon ; rags of wool- len, silk, and even leather clothing; the waste of manufactures in which horn, bone, hides, bristles, intes- tines, and other organic and nitro- genised materials are used; the spent animal or bone charcoal of sugar refineries ; the ammoniacal liquors of gas-works ; the alkaline wash-waters of soap, dye, bleach, and other factories. Almost num- berless matters have in this manner found their way into patented arti- ficial manures. The suggested modes of preparation are numerous, mechanical and chemical ; such, for example, as concentration by boil- ing down, precipitation by chemical agency, crushing, grinding, che- mical disintegrating by powerful solvents, maceration in water, torre- faction by fire, and digesting in superheated steam. Superphosphate of lime, first patented in 1842, has become a highly-valued manure. Several years ago the product in Great Britain reached 200,000 tons annually, and now it is much larger. Bone and minerals, if containing phosphoric acid, are made to yield it for purposes of manure. They are first ground to a fine powder by mill-stones ; the powder is passed into a lMg iron cylinder having agitators revolving within it ; sul- MAP 22T MAR phuric acid is admitted ; the acid and the powder, forming together a kind of mud, pass out of the cylin- der; the semi-fluid mass runs into deep pits, where it is left until it gradually solidifies. Bones imported from all parts of the world ; fossil bone earth, or coprolite ; bone ash from South America; animal char- coal from Germany all are rendered available in the production of phos- phate of lime. One kind of ma- nure, guano, on which a vast amount of money is spent annually by our farmers, is not a manufacture ; it consists of the droppings or refuse of sea-birds on lonely coasts and islands in South America. The quantity imported in 1867 was 1 92, OCX) tons, valued at ,"1,700,000, certainly an enormous money pay- ment for mere animal refuse. Maple. This very useful tree is highly valued in North America, where one variety of it, the sugar maple, is cultivated for the sake of the sugar which can be extracted from it ; while the wood has a beau- tiful silky lustre when smooth and polished. Bird's-eye maple and mottled maple are kinds which de- rive their names from certain diver- sities of surface when polished. The striped-bark maple is used in Ame- rica as a substitute for holly. The Norway maple is soft, but has a fine and pleasing grain. Maps. Considered simply as specimens of engraving and print- ing, maps do not call for notice here ; but thei'e are some special kinds which display much ingenuity. The Austrians have devised an inge- nious mode of producing contoured relievo-plastic maps. Maps are sometimes printed on oil-cloth for special uses. Maps printed on pocket-handkerchi f is have a consi- derable degree - usefulness, inas- much as they can be folded up in any way without injury. Maps in chromo-lithography, now produced in many varied forms, are particularly serviceable, seeing that land, water, and boundaries can be so nicely de- fined by this means. Embossed maps for the blind are among the excellent apparatus now provided at the several blind asylums. In mak- ing relief-maps, slips or ribbons of thin copper are laid down on a slate tablet, of such heights as to repre- sent the elevations of mountains and table-lands, c., and of such cur- vatures as to give the outlines of continents, islands, mountain groups, c. The model so pre- | pared is coated with plaster of I Paris. When dry, the surface is I scraped and rubbed until the edge 1 of each copper slip becomes visible. The model is, lastly, finished by painting in oil colours. There has been prepared an excellent relief- map or model of the Isle of Wight, 3 feet to a mile. Marble, as one of the most ad- mired kinds of stone, is largely used for statuary, and for the richest styles of decorative building. Its chief constituent is always carbonate of lime ; but there are also others, to which its colours, veins, mark- ings, and peculiar characteristics are due. Statuary marble and Furni- ture marble are two great divisions ; the latter being much subdivided according to its fitness for various purposes. The finest and whitest statuary marble is obtained from Greece and Italy, a circumstance to which the prevalent taste for sculp- ture among the Greeks and Romans was partly due. Black, turquoise blue, red, yellow, brecciated, varie- gated marble all are in request for some purposes or other. In Italy marble commands from ,24 to j6o per cubic yard ; but very large or fine blocks fetch much higher prices. Some of the Italian marble quarries are at the sides of precipitous mountains and cliffs, dangerous to approach and to work. Our own Derbyshire marble pre- sents many beautiful varieties of MAR 222 MAR black, rose-coloured, and russet ; and a brisk manufacture of marble com- modities is carried on in that county. The extrication of the marble from its rocky bed involves some such me- chanical processes as those described under QUARRY, QUARRYING, except that blasting is rarely resorted to, the substance being too valuable to tear and rend in this way. For the sawing, grinding, smoothing, polishing, &c., see STONE WORK- ING ; it being understood that all these processes are more carefully conducted with marble than with or- dinary building stone, as the former is more choice and costly. Additional polishing materials are used, to ac- commodate the softness of the mar- ble ; such as silver sand, pumice and water, snakestone, rubbers of woollen cloth on a wooden block, rollers of woollen cloth, putty pow- der and water, and linen rag with flour and water. Marble can be turned in a lathe, the turning tool being simply a pointed bar of steel ; the scratches are rubbed down by sandstone and water, and then ensue the grinding and polishing. By some or other of these processes are produced all the numerous varieties of balustrades, table-tops, chimney- pieces, flooring slabs, paper weights, vases, &c. Some of the mechanical processes of sculpture are noticed un- der STATUE CASTING, and imitation coloured marble under SCAGLIOLA. Marbles. Boys' marbles are made of stone broken up into small cubi- cal pieces, and worked by a mill in a series of concentric grooves until they become rounded by the abra- sion of the edges and points. In a rougher way, the rounding is effected by friction in a revolving wheel. Commoner marbles are made of clay, hardened by baking in an oven. Some, made of superior clay, are painted and coated with a vitri- fied glaze. Marbling- ; Marbled Paper. The edges of books, and sheets of paper employed in bookbinding, are often marbled in a remarkable way. Small round spots of colour ; a mar- ble veining on a shaded ground ; a pattern of spirals or curls ; spots upon a wavy ground are some of these varieties. The colouring sub- stances are the usual pigments em- ployed in painting. In marbling a sheet of paper, a solution of gum is placed in a large shallow trough ; colour is sprinkled upon the gum, in spots, shades, veins, curls, spirnls, &c., by the peculiar -action of a brush : a sheet of paper is laid dex- terously on the surface, and comes up marbled all over, the gum hav- ing a peculiar effect in diffusing the colours one among another. Some- times a wavy-striped effect is pro- duced by a comb passed over the surface of the colours on the gum. A modification of the same process marbles the edges of books. Marine Engines. The prin- ciples on which all steam-engines depend are noticed under STEAM ENGINE. Marine engines, for use on board ship, are affected in their shapes and action by the necessity of economising space as much as pos- sible. By far the larger number now made are horizontal engines for screw-steamers. In this form the build is more compact, the space occupied smaller than in any other. In many of them the action is direct, the stroke and connecting-rod short, and the cylinder of large diameter. In other cases a longer stroke and con- necting-rod are used. One variety, called the duplex horizontal-trunk engine, has the inside of the trunk made available for cylinder space by the aid of a fixed piston. Engines with concentric double cylinders, oblique screw-engines, vertical in- verted cylinder screw-engines, dou- ble cylinder expansive-engines are among the many varieties of engines now made for screw-steamers. In one, by Messrs. Rennie, the cylin- ders are at opposite sides of the MAR 223 MAS shaft; each cylinder is directly oppo- site the air-pump of the other; and each exhausts directly into the con- denser by its side. Marking Ink. Under INK the relations which the different kinds of ink bear one to another are briefly noticed. It may here be added that M. Gerke, a Russian manufacturer, has devised a mode of applying one of the known processes of dyeing to the production of a red marking ink. A preparation of madder in the form of a paste is applied by means of a stamp to linen intended to be marked, and previously wetted with acetate of alumina. A ma- chine for marking on linen has been invented by Jarrett ; it is a small, compact, self-inking press, simple and easy to work. To repeat the writing (or rather printing) many times in succession without using fluid ink, the same inventor has con- trived another press, with which carbonic paper, or some other che- mically-prepared endless band, is employed. It will yield a large num- ber of impressions before requiring change. This substitute for ordinary ink is adopted on account of the ten- dency of the latter to dry up and cake. The apparatus, with slight modifications, is applicable to the endorsing of documents as well as to the marking of linen. Marmalade properly consists of bitter Seville oranges, the rind and the pulp being separately boiled, and again boiled with sugar. But the cheaper kinds of marmalade have very little orange in them. So large is now this manufacture, that one single firm in Scotland produces no less than 250 tons of marmalade in a season. Various kinds of preserved fruits are made nearly in the same way. At the International Exhibi- tion of 1862 Messrs. Crosse and Blackwell displayed an interesting collection of such fruits, marmalades, and jams, among which was a sample of fruit jelly made from currants ga- thered in 1850. Messrs. Fortnum and Mason brought together a col- lection to illustrate these peculiar manufactures in almost every part of the world. Queensland distin- guished itself by citron marmalade, as well as pine-apple jam and grana- dilla jelly. Marquetry presents a sort of medium between Mosaic and Buhl Work (which see), in so far as it relates to the production of patterns by inlaying woods of different co- lours or different direction of grain. The woods may be of their natural colours or dyed to any required tints or shades of the same colour. Birds, flowers, scrolls, and devices of almost every kind may be thus made ; even portraits, though with an effect certainly not adequate to the amount of labour bestowed. The cutting out, and the insertion of the inlay in the foundation, are effected nearly in the same way as in buhl- work. This kind of decorative cabinet-work is not so much in fa- vour as it was a century ago ; but a useful kind of wood inlay is now in vogue, described under PAR- QUETRY. Masonry, as the application of stone to building purposes, involves a considerable amount of shaping and dressing to the stones them- selves, irrespectively of the placing and fixing. In the articles GRANITE, LIMESTONE, MARBLE, QUARRY, SANDSTONE, STONE WORKING, &c., a notion is given of the several ways in which stones are quarried, cut, chiselled, and smoothed ; and it will suffice here, therefore, to speak of the placing and fixing. (i.) Kinds of Work. Many modes of alternating large stones with smaller have prevailed at different periods. The Romans, in their masonry, employed the reticulated arrange- ment, with square stones laid dia- gonally; courses of stone of un- equal height ; a stone facing to a rubble heart, or centre ; and some MAS 224 MAS others. In later times blocks of stone were occasionally flat and upright alternately ; long and short consisted of stones very long compared with their width ; herring-bone work had the stones nearly upright, but placed diagonally, embedded in cement. At the present day some of the | older modes have fallen into disuse. Those most frequently employed are : Rubble-work, in which ir- regular stones are cemented into their places without being squared ; coursed-work, in which the stones are made somewhat more square and regular; rand ashlar-work, in which the squaring is rendered still more complete. Rubble is sometimes improved by introducing squared stones at the angles and the more prominent parts, with heading or band stones carried through the whole thickness of the wall. A rubble wall may either have cement or plaster, or may consist of stones large enough to hold together by their mutual weight and pressure. An ashlar wall may have its regular squared stones only on the surface, the hinder and hidden portion being of brick. Stone walls in London are generally not so strong as those in the North of England and in Scotland ; the greater costliness leading to the use of ashlar-work, which is weaker than solid stone. In the best ashlar band stones are placed here and there, running through the brickwork as well ; in commoner kinds timber band is used. (2.) The Tools. In the various processes of preparing, placing, and fixing the stone, tools are used of several kinds, but not complicated character. The saw (with a straight, and not toothed, edge) severs the stone into pieces. The wedge does the same thing in a rougher way, and for small pieces. The chisel, a small strong iron tool with a steel edge, presents much variety of shape. The mallet is a sort of large hammer with a short handle. The point is an iron tool which works the stone in narrow ridges and furrows. The inch tool, rather more like a chisel, works down the ridges. The boaster, still broader, smooths the work further. The broad tool is another of the same class. A stone axe aids in giving shape to an irregular piece. Kjedding axe, like a ham- mer with one flat face and one pointed, furthers the process ; and so does the cavil. The level aids in preserving horizon tali ty ; the plumb-line gives the vertical ; the square insures right angles ; while the bevel regulates the angle of sloping surfaces. (3.) The Working. Sometimes a cramp, or dowel, is used to assist in retaining the stones in their places, an irregular or dove- tailed piece of metal or wood cross- ing a joint from one stone to another, and secured to both. A joggle is a projection in the end of one stone, fitting into a cavity in the end of the next adjoining, something like the tenon and mortise of the carpenter. The joggle dowel is a third and separate piece of stone for this pur- pose. Various technical names are given to the modes of dressing the sur- faces of masonry ; such as pointing, 01 working with the point ; boast- ing, or working with the boaster ; stroking, or making parallel lines and ridges over the whole surface ; tooling* a modification of stroking ; droving, nearly like boasting ; broaching, or chiselling with a kind of punch ; picking, or the use of a cavil for very hard stone ; rubbing, or smoothing with sand and water. In curved work, whether convex or concave, the curves are maintained by the use of gauges, templates, &c. Sculpture or statuary work, in which the stone is not only shaped, but carved, is more an artistic than a mechanical employment, so much depending on the taste with which the workman realises the design of the architect. A beautiful example of this land of art is displayed in MAS 225 MAT the new Museum at Oxford, where all the capitals of the pillars differ one from another, each representing the characteristic parts of some one particular plant. Massicot is a protoxide of lead, used as a yellow colour. Mast. For small vessels the mast is one thickness or trunk of timber ; but for large ships it is made up of many pieces strongly riveted and hooped together. Hol- low iron masts are now frequently used, combining a good deal of strength with lightness, and at the same time acting as ventilating fun- nels. Mastic, or Mastich., is a gum that exudes from the mastic tree of South Europe and North Africa, and hardens into yellow drops. It is employed in making a beauti- ful, colourless, transparent varnish, largely used for varnishing prints and drawings. Mastic Cement is not properly named, being made of burnt clay, litharge, and linseed oil, without any gum mastic. Match. The slow match, the quick match, and the fuse are implements for igniting charges of gunpowder. (See BLASTING.) Matches. The way in which the demand for hundreds of millions of any particular article gives rise to a large branch of manufacture is curiously illustrated in the congreve or lucifer matches which are now in such general use. So far from great cheapness leading to the use of cheap materials, the proofs of it are not found in this manufac- ture ; for it is known to be even- tually more economical to employ sound and straight-grained timber, and the most perfectly-constructed machines to cut it. What kinds of contrivances preceded the lucifer match are noticed under LIGHT-PRO- DUCING APPARATUS. Lucifers are made as follows: (i.) The Splints. One mode of making the square splints is this : Pine planks are cut by circular saws into blocks, say ii X 4 X 3 inches each ; these are cut into slices by thirty or forty sharp knives fixed in a frame ; and each slice is cut into splints by a large knife, which comes into action just at the instant when the smaller knives have penetrated to a sufficient depth. Each machine will cut more than 1,000,000 splints in a day, each long enough for two matches. This is the principal, but not the only mode of making the very familiar square splints. The round splints are made in some such way as the following: A thick steel plate is perforated very closely with holes, the edges of which are made as keen as possible. A block of wood, with the grain in the proper direction, is pressed with great force against the plate, which separates it into little cylindrical rods by the action of the perforations. (2.) The Composi- tion. The problem being to find a composition which will catch fire by friction against a bit of sand-paper, it is not surprising that chemis- try has discovered many such. In practice, every lucifer-match maker affects to have a peculiar recipe of his own; but the ingredients gene- rally comprise some two or more of the following: phosphorus, sul- phur, nitre, sand, gum, glue, chlo- rate of potash, water, and colour- ing matter. Bryant and May's safety matches have this peculiarity, that one part of the composition (phos- phorus) is on the box, and another part (sulphur and chlorate of pot- ash) on the match. It is only by friction between these two that ignition is brought about ; friction on sand-paper, by a blow, or by crushing, produces no effect ; and on this ground these matches cer- tainly seem to have a fair claim to the name which has been given to them. When the composition, whatever it may be, is prepared, the matches are tipped. Tied up into convenient bundles, the splints are Q MAT 226 MAT dipped, each end in turn, in melted sulphur. When dry, they are tipped with the composition, being arranged in such a way in grooves that the ends of 50 or 100 can be dipped at once exactly to the proper depth. They are not dipped into a vessel, but the ends dabbed down, many at a time, on a hot plate which has a layer of pasty composition upon it. This trade is very dangerous, on account of the inflammable nature of the in- gredients. It is also unwholesome, owing to the fumes from the phos- phorus : this insalubrity is some- times sought to be avoided by using allotropic phosphorus, which gives off no fume. The splints, tied up in bundles, are cut with a circular saw into two matches each, either before or after the tipping. (3.) The Boxes. The ordinary boxes into which English lucifers and congreves are placed are made literally of a shav- ing ; for it is a kind of plane which shaves off a thin veneer from a smooth plank. A little gluing of wood or pasting of paper, or both, finishes the box. It is, in fact, a double box, for a box without a top slides into another box without ends. Some of the German boxes are cylindrical, but still they consist of a mere shaving, brought into shape with a touch of glue. Up- right metal boxes, with six sides, are made almost wholly by stamp- ing. In some of the German fac- tories there are machines of beauti- ful construction solely for making the boxes : a planing machine for preparing the wood, a machine for folding the oval and four-sided boxes, a machine for stamping metal boxes, Sec. Wax-taper matches tipped with composition, cigar-lights of various forms, safety cigar-lights, amadou and brown-paper fusees for cigars and pipe-lights all belong to the same general class as the lucifer; they depend mainly on the particular composition selected for the tipping. Some of the English match factories make as many as 10,000,000 per day. Austria has produced 50,000 cwt. in a year. Judging from the quantity of phosphorus used, a rough guess has been made that 250,000 millions of matches are made annually in the whole of Europe. Another estimate is, 2,000 million matches per day, using up 14,000,000 cubic feet of timber. Match Lock. (See GUN LOCK.) Mathematical Instruments, for drawing, mapping, and the like, require careful and delicate manu- facture, seeing that many of them are to be employed in measuring and graduating very small spaces and quantities. The scales, com- passes, drawing pens, pen-points, beam compasses, proportional com- passes, rulers, dividers, &c., all de- mand accuracy in their several ways. The use of steel, brass, box- wood, ivory, and ebony for these purposes is familiarly known ; but new materials are from time to time brought into requisition. The white mixed metal called electrum is fre- quently employed for these pur- poses. There are also scales and compasses made of aluminium bronze, which is admirably suited for the purpose, being very strong, receiving fine divisions or gradua- tions, and having but little tendency to tarnish. Some of the makers of ivory scales succeed in putting 200 divisions in an inch, every line beautifully clear and distinct; this has even been done on box-wood by a machine invented for the purpose. One kind of scale occasionally made is highly useful in engineering work, being a comparative scale of foreign and English measures ; a slider of brass or electrum traverses from end to end, the graduated edge of which enables any two scales to be com- pared, and converted into each other. Mats; Matting. The cocoa-nut fibrenoticed under COCOA-NUT PRO- DUCTS, when first used in England MAU 227 MED for mats and matting, was only at- tended to for the excellence of the fibre itself; but at the present time care is bestowed upon the patterns of the mats as well as upon the quality of the material. Messrs. Treloar and other manufacturers introduce much taste and fancy in some of the designs. Sometimes the pattern is produced by the mixture of other materials with the coir, especially the beautiful and easily-dyed fibre of the agave : coloured wool and cotton yams are also used with good effect. The agave fibre just mentioned has come into extensive use for a kind of article more nearly resem- bling cushions than mats ; it is wrought up into an excellent sub- stitute for curled horsehair, for stuffing the cushions of railway car- riages. At our last International Exhibition (1862) there was an in- teresting display of rush mats from Debreczin, in Hungary, remarkable for their lowness of price. Rushes of various kinds are, indeed, the chief material for mats ; but vegetable fibres of other kinds are employed for the same purpose in great va- riety. India-rubber is now em- ployed in a peculiar way for door mats of a somewhat expensive kind, having perforations to receive dirt and dust. India matting is made in vast quantities in the East. Mauve. (See ANILINE CO- LOURS.) Mead is honey wine or honey beer. The honey is mixed with water, fermented, and further treated as for thin or weak beer. Medals ; Medallions. (See COINING; DIE SINKING.) The chief distinction between a medal and a coin usually is, that the former is larger than the latter, and in higher relief. The stamping of a bold medal can seldom be effected with one blow, two or more being needed, and the metal annealed between whiles. In stamping, a press is used having a large wheel attached horizontally to the top of a strong and finely-threaded verti- cal screw, and a bed on which the die is placed. The blank which is to become a medal being laid in or on the die, the wheel is set to work ; this brings down the screw, and an intense pressure acts on the blank. If of soft metal, one blow will suffice ; if hard, two or more. Some bronze medals of large size and bold relief have required as many as thirty blows. Mediaeval Metal Work. The late Mr. A. W. Pugin may be said to have invented a new manufacture for Birmingham. In his enthusiastic efforts for the revival of Gothic architecture, he sought to reintro- duce as much as possible the prac- tical arts connected with eccle- siastical decorations and furniture. He found that the metal- work of old cathedrals and churches was far su- perior to that which English ma- nufacturers in his own day were in the habit of producing. ' In Mr. Hardman, of Birmingham, he found a willing coadjutor ; and a new trade began to be established in that busy town about the year 1838. Workmen were .gradually trained to produce well-wrought works in metal such as hanging lamps, can- delabra, chalices, flagons, metal mountings for mitres and pastoral staffs, and other articles used in Catholic churches and cathedrals. When the firm had become defi- nitely established as manufacturers of (what is now usually termed) me- diaeval metal-work, they executed, among other important commissions, the decorative metal-work for the new Houses of Parliament. In the formative or structural part of the work, the processes most adopted are casting, raising from thin plates, and forging. In the decorative or ornate part, often in costly metals, the pro- cesses employed are engraving, chas- ing, damascening, niello-work, ena- melling, incrusting, filigree-work, MEE 228 MER saw- piercin g, repousse work, gilding, parcel gilding, burnishing, &c. In some of the more elaborate produc- tions skilled artificers in all these branches are successively employed on the same article vying one with another in the combination of taste with dexterity. Concerning the growth of the trade Mr. Aitkin states : "Up to 1852 mediaeval metal-work- ing was confined to Messrs. John Hardman and Co. In that year three workmen, formerly in the employ of the firm, commenced business at Birmingham on their own account. Eventually the partnership was dis- solved ; and the result has been that there are now four separate esta- blishments in the town. Long be- fore this time, however as if War- wickshire, with its magnificent eccle- siastical and baronial remains of the mediaeval period, were determined to show itself worthy to be the cradle of this movement Mr. Skid- more, of Coventry, in 1847, enthu- siastically entered as a labourer in the same field, attracted by a power- ful sympathy in taste and feeling with the revivalists. He was at that time engaged in the jewellery trade, and his earliest works were chiefly executed in the precious metals ; but at a later period he essayed and accomplished larger works in other metals the roof of the Oxford Mu- seum, composed entirely ofwrought- iron, and the screens of Lichfield and Hereford Cathedrals, the struc- tural parts of which are of cast, and the ornamental of hammered iron, adorned and beautified with other metals." Meerschaum Pipes are made of a peculiar earth, the hydrated sili- cate of magnesia, found in Asia Minor, Greece, Moravia, and Spain. It is clay cut in lumps, which are first roughly squared into blocks, and exported to Austria, where most of the meerschaum pipes are made. If quite pure, the substance is delicately white, easily indented by the thumb-nail, and readily cut. If any impurities are with it, they impart a tinge which lessens its value. If hard, the earth is likely to be impure ; if soft, it is too porous ; and therefore the makers of the best pipes look out for a me- dium quality between hard and soft. In working it, the substance is soaked in a composition of wax, oil, and fat; and then the cutting and carving are carefully managed, often with a high degree of artistic skill. The parings and scraps are pounded, boiled, and moulded to blocks, to form inferior pipes. The cloudy co- louring which comes upon a meer- schaum pipe-bowl is a result of the action of the oil of tobacco upon the wax and oil with which the clay is saturated ; it is sometimes imitated artificially by steeping the clay in a solution of iron before the satura- tion with wax and oil. The Ger- man and the French names, meer- schaum and tcurne de mer, both mean sea-foam or sea-froth. Melting- Pots. (See CRUCIBLE, GLASS MANUFACTURE, &c.) Mercury is one of the most re- markable of all metals, being fluid at ordinary temperatures, and not solidified or frozen except by intense cold ; while it does not go off in vapour until a temperature is reached far above that at which water goes off in steam. This wide range of fluidity renders it a very useful heat- measurer or thermometer. Its spark- ling mobility led to the name living silver or quicksilver being given to it by the old alchemists. The chief properties of mercury are the follow- ing : It freezes or solidifies at 39 Fahr. (71 below the freezing point of water) ; malleable when frozen ; contracts in freezing (unlike water when freezing into ice); density thirteen to fourteen times that ot water ; boils and goes off in vapour at 660 Fahr. ; forms a finely-divided grey powder when mixed with sul- phur, sugar, chalk, or lard; does not HER 229 MET adhere to glass when pure, but forms isolated drops. The combinations of mercury with other substances are numerous, and some of them highly valuable in the arts. The alloys of mercury with other metals have a special name attached to them, that of Amalgam. (See AMALGAM ; AMALGAMATION.) The black, red, and yellow oxides are all useful for various chemical purposes. The nitrate is used in cleansing some kinds of skins ; it gives to the fur the property df felting for hat- making ; and from it also is pre- pared fulminating mercury. (See FULMINATING POWDERS.) One form of the chloride is the well- known white medicinal powder, calomel; another is the deadly corrosive sublimate ; while a third, called horn quicksilver, occurs na- turally as a yellow solid. One form of the sulphate produces the yellow turbith mineral. Two dif- ferent combinations of sulphur with mercury produce Ethiops mineral and vermilion. The latter beau- tiful pigment and dye is described separately. (See VERMILION.) Nearly all these combinations of mercury have the property of easily separating that metal from them, which greatly facilitates many pro- cesses in the arts and in chemistry. In the actual obtaining of this valu- able metal, the word quicksilver is almost always used instead of mer- cury. We refer, therefore, to QUICKSILVER MINING. Merino. Like many other terms applied to woven goods, merino is inconsistent. The fabric so called is a stuff of worsted yarn, usually from common sheep's wool; it is only the very superior kind that is made of the fine, long, soft wool of the merino sheep. A good merino differs from a stuff chiefly in this, that the latter has a coarser back, which renders the material heavy; whereas, by using both warp and weft fine, a merino can be made nearly as light and delicate as Cash- mere, whether the wool employed be really merino or not. Metallography is the name which M. Abate has given to an ornamental process devised by him in 1851. It is a method of trans- ferring to plates of metal devices engraved on wood blocks. The block is wetted with an acid or sa- line solution, the nature of which varies with the kind of metallic sur- face to which the transfer is to be made. The block is printed on the plate ; a solid precipitate is thrown down from the solution by chemical action, and this precipitate holds sufficiently on the surface of the metal to form a kind of picture. The process is ingenious, but has not yet come much into use. Metallurgy is the collective name given to those important operations whereby metals are separated from the various substances and impu- rities which accompany them in the ores. The operations form two groups : a mechanical separation of the stony accompaniments, and a chemical separation of those which are metallic. The stony substances are often classed together under the name of gangue, and their removal is described under ORE DRESSING. The final separation of the metals from the remaining impurities is the object of smelting, for which see the names of the chief metals themselves COPPER, IRON, LEAD, TIN, ZINC, &c. So enormous are now our manufactures in these de- partments, that we exported in 1867 metals in a partially-prepared state to the value of ^"20,000,000, irre- spectively of steam-engines, ma- chinery, &c. Metals. Metals differ greatly in density, varying from platinum, which has a specific gravity of 21-5 (21-5 times that of water), down to lithium, which is only 0-593 (little more than half the weight of water). The eight best-known metals stand MET 230 MET to each other in this respect as fol- lows : Gold, 19-3; mercury, 13-6; lead, 1 1-4 ; silver, 10-5 ; copper, 8-9 ; iron, 7-8; tin, 7-3; and zinc, 7-1. In hardness the metals vary from titanium, which can hardly be scratched by anything, to potassium and sodium, which are as soft as wax at ordinary temperatures ; while mercury is a liquid. In malleability they range from gold, as the most malleable, to frozen mercury, which is excessively brittle. In ductility the range is from gold to cadmium ; this property (admitting of the metal being drawn out into wire) not being exactly parallel with malleability (fa- cility of beingbeaten into thin leaves). In tenacity they vary from iron, down through copper, silver, gold, zinc, and tin, to lead ; while many of the rarer metals are too brittle to exhibit tenacity at all. In heat-conducting power the more useful metals range from gold to lead, iron occupying a medium position : this property has much to do with the selection of different kinds of metal for different purposes. In the capacity for heat (a different thing from the conduc- tion) the range is from gold at one extreme to tungsten at another. The expansibility, on being raised from 32 Fahr. to 212, is greatest in zinc, medium in gold, and least in platinum. In fusibility the range is from rubidium which melts below the heat of boiling water, to plati- num and its companion metals, which can hardly be melted at all. In volatility, or the comparative readiness with which they go off in vapour, they range from mercury, which begins to volatilise even at zero, to platinum, which can only be volatilised by electric action. Taking metals as a class, and setting aside individual differences, they all have metallic lustre, and they are all good conductors of electricity and of heat. It is difficult to name any other property which they have in common, except that they are all (apart from the alloys which they form one with another) simple sub- stances. It should be said, also, that although conductors of electricity when in the solid state, they are insu- lators when vaporised. There have been about fifty metals discovered, which may be classified in various ways according to their chief pro- perties. So far as concerns the re- quirements of the present work, the more important metals ALU- MINIUM, ANTIMONY, ARSENIC, BISMUTH, CALCIUM, CHROMIUM, COBALT, COPPER, GOLD, IRON, LEAD, MAGNESIUM, MANGANESE, NICKEL, PLATINUM, POTASSIUM, SILVER, SODIUM, TIN, and ZINC are described under these several headings. The less important such as iridium, lithium, palladium, rhodium, strontian, tungsten, &c. are mentioned incidentally connected with manufactures in which they are employed. Meter. In the measurement of gas, to determine how many cubic feet the company shall charge to the consumer, a meter is used, which is constructed in one or other of many different ways. ( I .) Wet Meter. This consists of a kind of drum, divided into compartments, all of equal and known capacity. The drum revolves in water, in which it is rather more than half immersed. There are numerous modes of ar- ranging the different parts of the apparatus ; but the general action is this all the gas from the street- mains to the house-pipes pass through the meter ; every cubic foot so passing gives a certain portion of one revolution to the drum on its axis ; and this revolution, through a train of wheels, acts upon index- hands, which tell of 1,000, 10,000, 100,000, 1,000,000, &c., cubic feet of gas. (2.) Dry Meter. Sometimes it is found that the water in the wet meter freezes in cold weather, and that some of the gas passes through without being registered. To ob- MET MIC viate these defects, many of the companies prefer dry meters. In these the gas is measured by the number of times that a certain quan- tity will fill a chamber capable of undergoing contraction and expan- sion by the passage of the gas. For this purpose the partitions in the meter are made of flexible leather instead of inflexible metal. The undulations of the leather affect certain arms and levers, which in their turn give motion to wheels and index-hands. The flexible leather being the characteristic of this class of meter, as water is of the other class, the particular modes of de- veloping the action are very nume- rous. To suit the requirements of different establishments, meters are supplied of various sizes, known by the number of lights which the gas is fitted to supply such as 2-light, iQ-light, $Q-light meter, and so on. A definite arrangement is made between the company and the con- sumer in regard to the meter ; and care is taken that the interior of the meter shall be so placed under lock and key as not to be tampered with. Methylated Spirit is one among many examples of the mode in which scientific discover}' cheapens the sub- stances used in the arts. Methy- lated spirit is an inferior kind of alcohol, mixed with one-ninth of its volume of pyroxylic spirit, or wood-naphtha. It may be purchased at about 4^. per gallon, while the same spirit without the naphtha costs many times as much. This difference is due to the fact that the Excise do not lay the heavy spirit duty on methylated spirit. The spirit ac- quires by the mixture a very unplea- sant taste, which renders it wholly unpalatable for drinking ; and as the chemists employed by the Ex- cise believe that this taste cannot be removed without decomposing the alcohol itself, it has been decided to leave methylated spirit untaxed. As a consequence, it is largely used in the arts in many processes for which spirit of wine used to be em- ployed. Chloroform is made by its aid ; but it is chiefly used for var- nishes, lacquers, and polishes. Metra. This name has been given by Mr. Mackworth, one of the Col- liery Inspectors, to a very ingenious and useful little instrument for va- rious kinds of measuring. Although only 3 inches square by I inch thick, it will solve a multitude of ques- tions likely to occur both in science and in industrial pursuits. It opens in two halves, which are hinged to- gether like a box. In one half is a mariner's compass, by which a miner can determine the direction of veins and strata ; sights, for taking altitudes or elevations ; a goniometer, for measuring the angles of cleavage and crystallisation; a plummet, for determining vertical lines ; a lens, to serve as a magnifier of small ob- jects ; a slide measure, to determine the thickness of wire and the size of meshes in the wire gauze for safety- lamps ; and a plate or film of tour- maline for certain uses in regard to the observation of springs and rivers. The other half of the box contains a level, graduated in de- grees of arc, and in gradients of an inch to a yard ; a graduated scale, to use with the goniometer ; a ther- mometer, graduated up to 140 Fahr. : a flat-chisel point, for penetrating the cleavage of rocks, &c. ; a thin sheet of transparent mica, to serve with appendages as an anemometer ; and a printed table of measures and formulae, relating to a variety of mat- ters connected with steam boilers, engines, ropes, specific gravities, boiling points, and the like. Mezzotint Engraving 1 . (See ENGRAVING.) Mica is a mineral of complex nature, found in veins and fissures, also as a component ingredient in granite and mica slate. It splits up into remarkably thin plates or MIC 232 MIL films, which have a peculiar glitter, something between pearly and me- tallic. So very thin and trans- parent are some of these films, that they are used as substitutes for glass in windows, lanterns, and even in optical instruments ; and when pounded they subserve other uses. Microscopes, considered simply as articles of manufacture, and not in relation to their scientific uses, are among the very highest develop- ments of metal-working and glass- working. So minutely accurate must all the parts be, that To^th f an inch, and in some cases TWo tn > * s regarded as a seriously large quan- tity. Some of the lenses for micro- scopes made by Powell and Lealand have only 2 V n f an i ncn focal length, a closeness which requires an accuracy of curvature almost in- conceivable. A great refinement in mechanical detail has been ren- dered necessary by the introduction of Wenham's binocular microscope, in which the two eyes look down two tubes to the object which is under process of magnifying: the constructional manipulations of the brass-work, to preserve the proper focalising under these conditions, are of the highest order, and can be executed by none but first-rate work- men. Where a microscope, as in some instanc.es, costs a hundred guineas or more, this high-class work is needed in every part. Messrs. Parker, of Birmingham, have sought to combine excellence with cheap- ness, by the production of a half- guinea microscope, capable of doing very excellent work. One of the Juries of 1862 stated that these in- struments " may be the means of introducing a healthy and inviting pursuit amongst large classes to whom more efficient instruments would be obviously unattainable." Milk. For the principal industrial processes dependent on the use o milk see BUTTER MAKING: CHEESF MAKING. Milk can be preserved or a considerable time in several ways. (i.) Sugar is added; the milk is evaporated to one-fourth of the bulk, soldered down in cases, steeped in boiling water, and cooled. (2.) Carbonate of soda and white sugar are mixed with the milk ; the mixture is evapo- rated, cooled to a solid, and pressed into square masses. (3.) Sugar and alkali are mixed with the milk ; the mixture is evaporated to the consistence of dough, dried, crushed, and bottled. (4.) Milk, boiled down to one-half, is beaten up with yolk of egg, simmered, skimmed, strained, and heated. The Tartars distil an intoxicating beverage from mares' milk. Milking- Apparatus. The Americans have invented and intro- duced a veiy curious milking appa- ratus, or cow-milker, to facilitate the work which in England is always done by fingers. It was first seen here during the International Exhi- bition in 1862 Acting as a kind of intermittent pump, it removes the milk from the four teats of the cow at once with great rapidity, and easily both to the operator and to the animal. The reporter on dairy ap- paratus at that Exhibition quaintly remarked that the cow-milker, " if sufficient practice be bestowed upon it at its introduction, is a very effi- cient apparatus." It may be doubted whether the time of dairy servants in England is sufficiently valuable to offer much inducement for the introduction of this curious appa- ratus. Millefiore Glass. (See AVEN- TURINE.) Millinery, as an article of trade, is veiy puzzling to Custom-house officers, owing to the difficulty of deciding what articles shall be in- cluded under that term, and what excluded. The Jury on Class 27 at the International Exhibition classed "general millinery" with "bon- nets ;" and this enabled them to MIL 233 MIN treat in succession of straw hats and bonnets, bonnets covered with vel- vet and other woven materials, arti- ficial flowers, dressed and dyed fea- thers, hats and plaiting of the fibre of the Australian cabbage tree, &c. All these relate to coverings and ornaments for the head, and such seems to be generally the applica- tion of the term millinery in rela- tion to women's attire. The amount of produce in these departments of clothing can scarcely be guessed at, so much does it lie beyond the scope of statistical tabulation. The Board of Trade and the Customs group " millinery " with " haber- dashery," but exclude " apparel ;" and this is perhaps nearly equivalent to placing women's clothing and men's clothing in different groups. Of millinery and haberdashery to- gether, after supplying home wants, we export to the very large value of ^5,000,000 annually. Mill ; MiU Work. Under FAC- TORY SYSTEM, FACTORY ACTS, is pointed out a certain confusion that exists between the terms factory and mill. The mills for grinding corn are noticed under FLOUR MILL; WINDMILL. The term mill-work is often used synony- mously with machinery. The steam- worked machines for making all kinds of machinery and mill- work, and the well-appointed establish- ments where such appliances are used, come for notice under MA- CHINE TOOLS; MACHINE WORK- SHOPS. Millstones. The best millstones are made of a peculiar stone found in small quantity near Paris, in a layer only equal to three millstones in thickness. The stone is a kind of silex, full of minute cavities, which greatly assist in holding and grinding the corn. Very large millstones are built up, segments being held together by strong iron hoops. Millstones are made of somewhat lower quality, but in much greater quantity, at Nieder- mendig, on the Rhine ; the stone is a kind of hard, porous lava, supposed to be of volcanic origin. Mineral Statistics. In addition to the various details given under the names of the principal metals and minerals raised in the United Kingdom, the following figures are very important, relating as they do to the year 1867, and derived from the records kept by the School of Mines : Tons. Iron ore . 9,965,293 Iron pyrites . 116,889 Copper ore . 158,544 Tin ore . . 13,649 Lead ore . . 93,450 Zinc ore . . 13,489 Nickel ore . 2 Manganese . 808 Coal. . 104,501,249 Salt . . 993,880 Ochres . 5,480 Value. ^2,936,323 67,454 699,694 694J34 1,158,272 41,241 16 1,618 26,125,312 223,011 5,808 These were the values of the several minerals when fairly raised to the surface. There was also an item of 3,241 tons of gold quartz quartz containing a minute percentage of the precious metal : an item in our mineral statistics which many readers would hardly expect to find. Another tabulation relates to the value of the metals actually obtained from the several kinds of British ore : Tons. Value. Irqn . 4,773,771 ^11,934,427 Copper Tin Lead Zinc Gold Silver 10,233 8,700 68,437 3,758 Ozs. 1,520 804,024 531,761 779,203 1,337,507 79,693 5,320 215,400 There are a few discrepancies in the two tables, probably due to the fact that some British ores were exported unsmelted. Nickel and manganese are here omitted, as trifling items. The quartz appears to have yielded MIN 234 MIX only half an ounce of pure gold per ton. The silver was mostly obtained from lead by Mr. Pattin son's beauti- ful process. Mineral Substances useful in the arts are so exceedingly nume- rous that it is difficult to classify them. First come the various kinds of stone and slate available for building and engineering purposes. Then marble, alabaster, gypsum, sand, gravel, clay, loam, marl, lime, chalk. Next, the varieties of gem, precious stone, spar, and crystal. Still more important than these, the ores from which are obtained iron, copper, tin, lead, zinc, gold, silver, nickel, and the whole range of metals. The coal series claims a place by itself, for, though a mineral to us, coal had a vegetable origin. Hone- stones, emery, black-lead, alum, fuller's earth, sulphur, phosphorus, nitre, borax, salt, soda, potash all help to swell the list of mineral substances on which the skill and industry of our artisans are em- ployed. Mineral "Waters, when artificial, are mixtures of certain substances with plain water to make it medi- cinal, effervescent, or refreshing. They comprise soda-water, lemon- ade, potash water, seidlitz water, chalybeate water, carrar'a water, seltzer water, carbonic-acid water, eau de Vichy, and many others ; and in these the mineral substance that is added is one or other of a long list carbonic acid, carbonate of soda, bicarbonate of potash, chloride of sodium, carbonate of magnesia, salts of iron, tartaric acid, tartrate of soda, &c. So far as regards the actual making, soda- water will illustrate the class. Water is mixed with sulphuric acid and carbonate of lime in a leaden vessel ; the sulphuric acid com- bines with the lime, and sets the carbonic acid free. This last-named is forced into a vessel filled with water, which becomes brisk and sparkling. To make true soda- water a little carbonate of soda is added ; but many of the kinds sold in the shops contain none of this salt, and are really only carbonic- acid water. An apparatus called a gazogene is employed to make it on a small scale. The gas, produced by mixing the chemicals in one halt of a vessel, is driven through a tube into the other half, where water absorbs about five times its own volume of it. Many mineral or aerated waters may be made by this means. The sweetness and the fruity flavours of many such waters are produced by simple mixing with the water. The natural mineral waters are springs, the water of which is impregnated with iron, sulphur, lime, soda, lithia, magnesia, &c. Mining*. Th$ art of extracting mineral riches from beneath the sur- face of the ground was one of the earliest, after agriculture, to which men applied their ingenuity. Most of the valuable metals, to which mining is chiefly applied, exist in ores or stony masses, and are at some considerable distance below the surface ; requiring, therefore, much digging and raising to ob- tain the ore, and many kinds of process to extract the metal. Some- times, where metalliferous veins exist high up a mountain, the moun- tain streams contain, in their beds or their sides, much metal in the gravel, sand, and mud washed down gradually by rains and running water ; the alluvium is in such cases washed and sifted, and the metal separated for smelting. In Eng- land the stream-works produce tin in this way; and in some foreign countries gold and platinum are thus found in addition to tin. In most instances, however, the ground has to be dug with pick and shovel to get at the ore. Iron, copper, tin, and lead are the chief metals with which England and Wales are en- MIN 235 MIN riched. Although each kind of metal calls for its own particular de- tails in extraction, yet mining pre- sents a general similarity for them all. The great depth to which the diggings sometimes go has called for the use of inventive skill in the modes of raising ore and raising and lowering workmen ; while the floods of water met with in the mine have always required powerful pumping apparatus indeed,the steam-engine first became a mighty machine on account of the wants of the miners. The locomotive and the railway may be said in like manner to have had their birth in the mines; for the tramways at the collieries, and the locomotive to draw the trams or waggons, preceded the passenger railways. Most of the mines of Cornwall and Devon are worked by companies, who pay the landowner by means of a percentage or royalty on the produce ; and as all parties are interested in knowing the actual richness of the veins, the royalty differs very much in amount in different instances. There are agents and captains to superintend the operations ; while the bargains with the miners are planned in the curious manner described under TUTWORK AND TRIBUTE, (i.) De- posits of Ore. The ore which is rich in metal is distributed in rocks of various kinds, and in portions vary- ing greatly in amount. It may alternate with beds of hard rock, or may occupy cracks and fissures in rocks, or may occur in rounded nodules or separate fragments. Cracks containing metallic ores are veins and lodes ; those containing non-metallic minerals are dykes and cross-courses. The veins or lodes are the only parts which yield profit ; and therefore the richness of the mine depends on the ratio between the quantity of vein and the quantity of rock or country (as the miners call it). The veins greatly vary in width, thickness, length, dip, and direction ; so much so that the prospective value of any one vein is very problematical. And not only so, but a vein may vary so much in richness in different parts, that a width of 3 inches may be better worth working than one of 30 feet. Most of the rich veins run nearly east and west, and not far from vertically. The "veinstone, or contents of the vein, consists of gangue and ore: the former stone withoutmetal,thelattera metallic earth or stone. (2.) Discovery of Veins and Lodes. As the metallic deposits are not visible at the surface of the ground, the miner adopts many modes of finding out where they are. A quarry or excavation will sometimes accidentally lay bare a lode ; or a test may be obtained by boring ; or shoadstones (isolated fragments) may serve as a clue ; or water flowing from a particular spot may be found impregnated with metal; or trenches may be cut in alluvial soil by a process called costeening ; or a horizontal adit, or level, may be excavated into a hill from the sides of a valley ; or in- ferences may be drawn from the direction of neighbouring veins. (3.) Sinking the Shafts. The position of the vein being approximately ascer- tained, and the commercial and work- ing plans of the company settled, the ground is opened in two ways by sinking a shaft down upon the vein, and by driving an adit or level from a neighbouring valley. Either or both of these plans are adopted, according to circumstances. In both kinds there is much digging, and much propping of sides and roof with timber. Shafts are mostly vertical, though sometimes a little inclined, and are dug in the solid rock ; while horizontal cuttings, at various depths, connect the shaft with the veins. The miners speak of sinking a shaft, and driving a gallery or horizontal passage. The galleries are usually about 6 feet high by 3 or 4 broad ; and access to MIN 236 MIN various parts of the vein from them is gained by cross-cuts. There are often several adits, or day-levels, opening at different heights into an adjoining valley, to aid in examining the mine, working it, and pumping it ; some of these are several miles in length, one adit draining a number of mines in common. (4). The Miner and his Tools. There is not so much real digging in a mine as many persons would suppose. Much of the rock is brought down by blast- ing, in which jumpers, hammers, scrapers, and tamping liars are used, aided by Hasting cartridges and safety fuses. The miner's other tools are chiefly the pick, the wedge or gad, and the shovel* He is lighted chiefly by candles (some- times stuck in his hat), and in explosive coal mines by the safety- lamp. The ore is wheeled in bar- rows or trucks along tramways to the bottom of the shaft, whence it is hauled up by steam or water power. Some of the hauling engines employed will raise 400 tons in twenty-four hours, from a depth of 1,000 feet, at a cost of zd. or 3^. for coals for every ton raised. The ropes employed are flat wire, round wire, flat hemp, and round hemp chiefly the first. For more detailed information on various points see BLASTING ; COAL MINING ; MIN- ING LADDERS ; MINERS' CAGE ; ORE DRESSING; PUMPING EN- GINES ; SAFETY LAMP ; TUTWORK AND TRIBUTE ; VENTILATING MINES. Mining Ladders ; Miners' Cage. So deep are some of the coal and tin mines, that it becomes almost insupportably laborious for the men to descend to their work, and still more to ascend when the day's work is done. Some of the mines now reach a depth of 2,000 feet. In old times the ladders, about 50 feet long each, were placed nearly upright, to leave clear space in the shaft ; afterwards, to ease the men, the ladders were shortened and placed more sloping, so that the series should form a zigzag from top to bottom, the bottom of each ladder resting on a platform, or sollar. It used to take a man an hour to ascend the shaft of a very deep mine. A man-engine has been adopted in Cornwall to facilitate the ascent and descent. Two timber rods, placed side by side, extend ver- tically from top to bottom ; each has a reciprocating up-and-down motion, with a range or distance of 6 feet ; and each has a number of stages, also 6 feet apart. By stepping across from a stage on one rod to a stage on another, backward and forward, the miner (while descending) con- trives to be always on one particular stage during the descending move- ment of that particular rod ; and vice versa during his ascent. The descent and ascent are thus made with very little muscular exertion. The rods are kept in up-and-down motion by steam power or water power. In coal and iron mines the more usual practice is to ascend and descend in cages suspended by chains or wire ropes, and worked from above. Sometimes the rope breaks, the cage is dashed to the bottom, and the men killed; and sometimes, by overwinding, the cage is drawn too high and tipped over the framing at the top, with equally fatal results. To obviate these disasters, various forms of safety-cage have been devised, em- bracing many ingenious contriv- ances. In mines of less depth it is not unusual to have an iron plat- form nearly the size and shape of the horizontal section of the shaft ; the men stand upon the platform, and are raised and lowered by steam power. Minium. (See RED LEAD.) Mint is the English name for a Government coining establishment. There is only one in England, the Royal Mint on Tower Hill; although MIX 237 MIX a distinguished Birmingham firm (Messrs. Heaton) is employed by it to make some of the copper and bronze money. There is also a mint at Sydney, in Australia, established by royal charter. The English kings, ever since the days of the Anglo-Saxons, have claimed the right of coining the national money too often with a view to make a profit out of it at the expense of the people. The coins were at first made by pouring melted metal into moulds ; but a better plan was afterwards devised of stamping them with a die. On many occasions the minter, or master of the mint, made a contract with the king to coin all the money at a certain price, such as to realise a profit for himself. The present system at the Royal Mint, a result of extensive and gradual changes, was organised in 1851, and placed under the management of a master, deputy-master, assayers, and other officers. Any person may send gold bullion to the Mint to be coined into sovereigns : prac- tically it amounts to this, that the Mint buys the gold at the ascer- tained value, and pays for it after- wards in an exactly equivalent quantity of gold coin, not seeking to make any profit by the transac- tion. Matters have settled down into such a system, that all the gold to be coined is sent to the Mint from the Bank of England, certain commercial advantages resulting thereby. The gold is mostly sent by the Bank in large quantities at a time, in ingots of about 180 ozs. each, previously assayed with great care, and every ingot specially marked and registered. The most scrupulous care is then taken at the Mint to insure the due accounting for every atom of gold received, and to bring it to the proper standard before coining. The arrangements are ra- ther different with silver : the Mint buys from all comers, at a price per ounce depending exactly on the quality; old Spanish dollars being very willingly taken on account of their excellent standard. In regard to the mints for copper money at Birmingham, Mr. Heaton states that Boulton's establishment was at work until 1850, when it was dismantled and the machinery sold. Most of the working plant passed into the hands of Messrs. Heaton, who erected new pre- mises for working it. Between 1850 and 1860, Messrs. Heaton's mint was the only coining establish- ment in England, with the exception of the Royal Mint on Tower Hill. In the last-named year Messrs. James Watt and Co. erected a new mill at Smethwick, a busy suburb of Birmingham. In the same year, also, Messrs. Heaton's mint was en- larged, in order to meet the enor- mous demand consequent on the new bronze coinage for the United Kingdom, and new copper coinage for several continental countries. The two great establishments have, between them, more than thirty lever and screw coining-presses. The pro- duct is enormous, for it amounts to thousands of tons of copper and bronze money in the course of a few years. Not only is England sup- plied from Birmingham, but also India, Italy, France, Turkey, China, Hayti, Venezuela, Canada, Chili, and other countries. In sixteen years the two firms (principally Messrs. Heaton) made 7,500 tons of such coins, to the value of ^2,500,000. In making 1,720 tons of new bronze coins, Messrs. Heaton employed and wore out no fewer than 17,000 steel dies. The actual processes of coining, with many collateral mat- ters associated with them, are de- scribed under ASSAYING ; BRONZE COINAGE; COINING; COINS; DIE SINKING; GOLD-WEIGHING MA- CHINE ; PYX ; STANDARD, STER- LING. The Mint, so far from a profit to the State, is a slight loss ; for a parliamentary vote is needed MIR 238 MOL to defray a small excess of disburse- ments over receipts. Mirror. (See SILVERING ; SPE- CULUM.) Mixed Fabrics. This name re- fers to a vast and ever-growing de- partment of manufacture, chiefly in the West Riding of Yorkshire. Be- sides the various goods in cotton, flax, silk, and wool, ingenuity is always at work in devising com- binations of two or more of them ; and these constitute mixed fabrics. The technical names nestings, coatings, tweeds, linings, cravat- ings, $laids, tabinets, poplins, Pa- ramattas, Cashmerettes ', cassinets, challis, bareges, Cashmeres, shawl- cloths, are only a few among those applied to mixed goods. It is al- most like a sum in permutation to determine the number of ways in which a certain number of materials may be combined ; and the manu- facturers are ever on the look-out for new combinations. Besides the four well-known kinds of fibre above mentioned, there have been added three others to the list in re- cent times alpaca and mohair for fine goods, and jute for coarse in- somuch that seven elements now enter into the permutation. Some- times the warp, sometimes the weft, sometimes a nap or pile at the sur- face, is the point most attended to ; in some cases yarns are dyed be- fore weaving, in others the cloth is printed after weaving; in some the Jacquard loom is employed to give a pattern to diversely-coloured threads. Bradford, in Yorkshire, is the great centre of this manufacture ; but Halifax, Huddersfield, and other busy towns in the West Riding also produce a vast quantity of mixed fabrics. Mohair is the wool of the An- gora goat, which is to Asia Minor what the alpaca is to South America. The wool is white, long, fine, and silky, and is employed for some of the finer goods made at Bradford and Halifax. Alpaca and mohair together we imported 3,500,000 Ibs. in 1867, chiefly to work up in the Bradford district. Moire is a name given to the watering or clouding which woven silks sometimes undergo. In order to produce the proper effect, the silk is usually of rather stout texture. Very little moisture is used, but very heavy pressure ; and the man- ner in which the silk is folded aids in producing the diversified effects. An examination of a piece of watered or moire silk shows that some portions of the threads have been pressed nearly flat, thus affect- ing the reflection of light in such a way as to produce the peculiar re- sults. Sometimes the pressure (by the hydraulic press) is so enormous as to amount to 100 tons. Moir6 Mtallique is a very pretty example of the crystallisation of a thin film. When an acid attacks a surface of pure tin, the surface becomes beautifully mottled by the crystallising of a thin pellicle of the metal. A piece of tin plate (sheet-iron coated with tin) is well cleansed by washing in potash water, then rinsed and dried. The clean plate is made warm, washed with a solution of nitric and hydrochloric acids, then dipped in water, washed, and dried. Very soon distinct crystals of tin ap- pear on the plate, large or small according to different modes of applying the acid. The plate is finished with a coating of transpa- rent and slightly-coloured varnish. Various articles of ornamental ma- nufacture, made of tin prepared in this way, present a very pleasing appearance, having something of the moire or watered effect noticed in the last article. Molasses. The drainings from sugar during the process of granu- lation constitute molasses. (See SUGAR MANUFACTURE.) 360,000 cwt. was imported in 1867. MOR 239 MOR Mordants are chemicals which give fixity to certain dyes and co- lours upon cloth. The philoso- phy of mordants, in regard to their chemical action, has been succinctly stated in the following way: In order to make dyes and mordants adhere to cloth, they must be reduced to their ultimate molecules. The mordants selected for use in any particular case are in- soluble of themselves in water ; hence their particles must be sepa- rated and divided by solution in some other liquid. This other sol- vent will exert in its own favour an affinity for the mordant which will prove to some extent an obstacle to its attraction for the cloth. Hence, again, such solvents must be selected as have a weaker affinity for the mor- dants than the mordants have for the cloth. As the combination to be brought about is merely the result of a play of affinities between the solvent and the cloth, the cloth will retain more of the mordant when its solution is more concentrated. It follows that, in practice, mordants must be selected in various degrees of concentration, according to the effect required to be produced ; and this is regulated by varying the pro- portions of the liquid in which the mordant is dissolved. (See CALICO PRINTING; DYEING.) Moreen is a thick worsted stuff specially woven for use in window curtains. It has no other resem- blance to merino than in being made of wool. Morocco Leather. (See LEA- THER DRESSING.) Mortar; Cement. The numerous mixtures called in some instances mortar, and in others cement, present themselves under many groups, but generally contain lime as a prin- cipal ingredient. The articles CON- CRETE, GYPSUM CEMENT, HY- DRAULIC CEMENT, and ROMAN CEMENT notice four of these groups. Mortar, as familiarly understood, is the kind which is used as a cement or binding material in ordinary brick- work. It is made chiefly of slaked lime and siliceous sand. If there is any clay in it, the name mortar is usually changed to cement. Rough sand is better than smooth ; the quality de- termines the proportion, which in an average way may be stated at 3 sand to I lime. The sand is laid out in a sort of hollow or basin form ; water is added to slake the lime ; and the sand is shovelled over to cover it. After a time the two are well worked up together, and passed through a wire screen. The mortar-mill combines the ingre- dients by means of a miJlstone re- volving on an iron bed ; and there is also used another form of mill, in which rakes are attached to a re- volving horizontal wheel. 72 bushels of stone-lime and 18 cubic yards of sand will make 315 cubic feet of mortar. Mortar, differing in its degrees of excellence, is used for cementing bricks, for cementing hewn stone in masonry, and for rubble- work when flints and frag- ments of stone are placed by hand in the midst of a thick layer. Va- rious other kinds of cement used in the arts, distinct from the lime groups, are noticed under such headings as CEMENT, GLUE, &c. Mortar; Mortar Vessel. A mortar is a gun with a very short and very wide bore. The largest mortars generally used are 13 inches calibre, but the French have had one of 24 inches ; and there is r. 6d. each. Muslin is the finest kind of cotton fabric. The Hindoos excel in spinning and weaving it, owing to the suppleness and delicacy of MUS 245 MUS their fingers. . It is not yet quite decided whether machine-made mus- lin has ever equalled the finest Dacca muslin; Manchester contends for the affirmative, India for the negative. In 1863 Dr. Forbes Watson caused two European and two Dacca specimens, the finest ever known up to that time, to be minutely examined. The result was, the Dacca muslins were the finest, both in the diameter of the yarn and in the number of filaments com- posing it. The yarn in the finest of these exquisite muslins was only =-0 inch in diameter. The em- broidered-muslin trade of Ireland is one of considerable importance to that country. It had its origin in Scotland, and has always been closely connected with Glasgow firms. At first it consisted chiefly in tambouring trimmings, collars, robes, and baby linen. When flax- yarn spinning by hand began to be superseded by machine-spinning, many women and girls were thrown out of employment ; and then it was that manufacturers thought of extending the embroidery trade by making use of the surplus labour thus rendered available. Schools were opened, in the West of Scot- land and the North of Ireland, to teach the art to children; and a good supply of various degrees of skill was in this way secured. By degrees the Glasgow manufacturers increased the varieties of work, introducing satin-stitch and sewed embroidery. They next introduced the improved plan of printing the pattern on the muslin by means of lithography instead of by block- printing enabling that to be achieved in a few hours, and for a few shillings, which used to cost weeks in time and pounds in money, and giving greater scope for artistic design. The Glasgow firms have found the Irish women and girls very willing to engage in this work ; and it has been the means of giving steady employment to vast numbers of them over a great part of the North of Ireland. It has been esti- mated that as much as ^600,000 a year is distributed as wages to the muslin embroiderers. For printed muslins see CALICO PRINTING. Muslin, Incombustible. Under FIRE-PROOFING mention is made of several ways in which woven goods may be made more or less incom- bustible. A remarkable series of experiments have been made in this matter in relation to muslin. A few years ago, after some distressing ac- cidents to dancers on the stage by the igniting of their gauzy muslin dresses at the foot-lights, the Queen requested Professor Graham to insti- tute some inquiries on the subject, with a view of ascertaining whether any means could be devised of ren- dering such textile materials non- inflammable. Messrs. Oppenheim and Versmann, deputed to the duty, experimented on more than forty chemical solutions, comprising car- bonates, silicates, phosphates, sul- phates, tungstates, chlorides,- oxa- lates, bromides, iodides, &c., of va- rious kinds. They obtained favour- able results with four only, phos- phate of ammonia, sulphate of am- monia (the first of these combined with chloride of ammonia), and tung- state of soda. Sulphate of ammonia was found to be the best as well as the cheapest. Muslin dipped into a solution of this salt is found to bear fire and flame remarkably well. It acts nearly in the same way, whether the muslin is plain or printed. After six months, muslin so treated has been found unchanged in colour or texture. Where dresses, curtains, &c., are to be ironed after washing, tungstate of soda is con- sidered to be better in some respects than sulphate of ammonia. Mustard. There is a* little both of chemistry and of mechanism in the manufacture of mustard. Two species of seed are used, the black MUS 246 NAI and the -white ; the former being the more pungent, but the latter more easy to separate the skin from the powder. Mustard is most pungent when the skin or husk is retained ; and hence it used to be the custom of mustard-mills to grind up the whole of the seed into meal ; but a taste arose for flour of mustard, the fine meal deprived of the skin, and hence the necessity for a dressing or winnowing process. The yellow colour is a falsity, a mere fashion, produced by adding other substances I to the mustard ; capsicum is given | to impart false pungency ; and yel- j lowish corn-flour to increase bulk, j insomuch that the mustard of the i shops is anything but a simple con- | diment. A useful oil of mustard can j be expressed from the seed. Myrrh, is one of the numerous gum resins obtained by incision in the trunks of Oriental trees. It comes to us in the form of small brown drops, and is used in vari- ous ways as a medicine and a per- fume. N. Nacre is one of the names for Mother-of-Pearl (which see). Nailers; Nail Making. Nails are still made very extensively by hand, although machines are coming more and more into use. Prom spikes and large carpentry nails, down to hobnails, brads, and tacks, the variety is considerable. Horse- shoe, wheelwright, hurdle, pail, deck, scupper, -mop, rose, clasp, diamond, flat, sharp, spear, fine, bas- tard, clout, counterclout, sparable, gate, clench these are only some among the numerous kinds of nails. Hand-made nails consist of iron rolled for the purpose, and cut up into pieces. The points are worked red-hot by the hammer at the forge. The heads are usually made by the aid of some sort of vice, which regulates the spreading out of the soft iron under the blows of the hammer. The nailers or nail- makers live chiefly in the Dudley district, where they make wrought nails (as they are called) with amaz- ing rapidity. Some nail rods are made by machine, out of sheet-iron, equal in thickness to the thickness of the nail. One kind of machine for this purpose is called rolling- shears : two rollers, with fillets and grooves on their circumference, catch hold of the iron, and speedily cut it up into square rods, from which the nails are afterwards made a much quicker way than rolling the rods as for rod-iron. At the Paris Exhi- bition, 1867, there was a nail-cutting machine, by the Wickersham Nail Company, of the United States, which cuts nails out of plate-iron with wonderful rapidity. One blow produces shank, head, and point. To cut nails 2^ inches long out of plate-iron S a 2 ' inches thick, the ma- chine makes nearly 120 revolutions of the driving-shaft per minute, and cuts eight nails at each revolution, making upwards of 1,000 nails per minute. Mr. Robinson's nail-making machine, patented in 1866, acts on the self-feeding principle, in such a way that one person can attend to two machines, whereas in those which are hand-fed each machine requires an attendant to feed it. In most of the machines hitherto invented the strip of metal employed has a width equal to the length of the nails which are to be cut from it ; thus, I J-inch nails would require i|-inch strip. In Robinson's machine, however, a strip four times as wide as the length of the nail may be used, and four rows of nails cut from it, thereby saving time in the cutting of the strips beforehand. Another improve- ment claimed is, that the nails, un- NAN 247 NAP like those usually made, do not be- come hardened in the cutting, and require no annealing. Among the marvels of Birmingham industry is the fact that 16,000 tons of cut nails are now made in that town every year. The first makers of cut nails by machinery were heavy losers, but the trade is now a prosperous one. Notwithstanding the advance in ma- chinery, there are still 20,000 hands employed in England in nail-making on the old plan. Nankeen, or Nankin, is the name of a cotton cloth which was at one time much used in England for men's trousers and women's pelisses. It derived its name from Nanking, or Nankin, in China, where it is supposed to have been first made. The cloth (a kind of strong calico) was made from cotton of a yellowish colour. When the English manufacturers took up this branch, they used white cotton, and dyed it to the proper tint of yellow by means of alum, oak bark, arnatto, and other substances. English nankeens are now largely exported to India, and even to China. , Naphtha is the type of such an amazing number of inflammable substances that chemists themselves do not yet know the limit. Naphtha, petroleum or rock oil, wood spirit, wood naphtha, acetone, coal naphtha, paraffine, photogen, shale naphtha, caoutchoucine, shale oil, sherwoodole, naphthaline all these names are given to various kinds, in some cases two names for precisely the same kind. Some are derived from the mineral kingdom, some from the vegetable. The liquid originally called naphtha exudes from the ground in Persia. Petroleum, or rock oil, is pumped up from natural springs or wells in Canada and the United States. Coal naphtha, dis- tilled from coal-tar, and shale naphtha, distilled from shale, are nearly allied to rock oil in chemical qualities. It is from a kind of shale naphtha that paraffine is usually obtained. Rangoon tar, rather like a grease than an oil, is the Burmese form of petroleum. These various liquids and semi-solids undergo numerous processes when they are required in a pure or refined state ; but all of them are inflammable, and more or less suited to be used as oil for lamps. Some of them, it is expected, will become available as liquid fuel for furnaces, con- cerning which matter careiul experi- ments are in progress. Other uses of these naphthas (one or more of them) are as solvents for gutta percha and india-rubber; as solvents for sulphur and phosphorus ; as liquids for preserving potassium and other oxidable metals ; as a source for the beautiful white solid paraffine made into candles, and a paraffine oil available as a lubricant for ma- chinery ; as agents for removing grease spots from silks and satins. So extensive are the links of con- nection between all these substances, that they include even asphaltum and bitumen, which, although solid or semi-solid, have nearly the same chemical characteristics as pure petroleum and rock oil. Naphthaline, one of the many products of coal naphtha, is gra- dually becoming very important in the arts. The French chemists have found a convenient mode of obtain- ing benzoic acid from it, and this acid is the starting-point of the ma- nufacture of the beautiful aniline colours. A new acid has also been obtained from naphthaline, which dyes wool an intense red without the aid of any mordant, and pro- duces valuable colouring agents by combining with other substances such as a beautiful golden-yellow pigment with lime, a fine orange with barium, a deep madder-red with aluminium, intensely bright red with copper and mercury, rich red- brown with zinc and cadmium, a fine garnet coloui with nickel and NAP 248 NAU cobalt, a nasturtium colour with lead, and some very brilliant new tints in combination with aniline and rosa- niline. Naphthalising- is a process to some extent employed in increasing the brilliancy of street gas. It con- sists in mixing the gas with the va- pour of naphtha in a vessel called the carburetter or naphthaliser. There may be as little as two, or as many as twenty, grains of carbon absorbed by every cubic foot of gas, according to the extent of surface of naphtha with which the gas is enabled to come in contact. Threads or wicks saturated with naphtha are found to increase this amount of action. The temperature of the ap- paratus, and the rapidity with which the gas passes through it, also in- fluence the completeness of the car- buretting process, and the increase of brilliancy in the light. A car- buretting apparatus has been applied to some of the street lamps in the city of London, to test the validity of the process. Coal-tar naphtha is better for the purpose than petro- leum or paraffine naphtha, being richer in carbon. It is only in poor gas, such as that with which the metropolis is lighted, that the naph- thalising process is deemed worth trying; the cannel coal of the northern counties yields gas suffi- ciently rich in carbon. Naples Yellow is a combination of the oxides of zinc and lead with antimony, useful as a paint or pig- ment. Natron is the commercial name for an impure carbonate of potash, obtained chiefly from the natron lakes of Egypt. It requires much refining before it becomes pure alkali. Nature Printing- is a name given to a peculiar process, gradually de- veloped by many inventors on the Continent, and by Mr. Henry Brad- bury in England. In one form of the process, to print impressions of leaves, fibres, lace, &c., from these objects themselves, the object is placed upon a polished steel plate, a heated leaden plate is laid on it, the two are pressed together, the object makes an indentation on the soft leaden plate, and impres- sions on paper are taken from this indented or intaglio device. In another form an impression of the object is taken on a layer of gutta percha, or on a sheet of soft lead ; a cast from this mould is taken by electrotype; and impressions are taken from the electrotype by sur- face-printing. In a third form the graining or other markings of wood are made to print themselves. The wood is wetted with dilute acid, and laid upon paper, calico, or a na- tural leaf; pressure transfers the markings of the wood to the paper, &c., and these markings become visible by the application of a mode- rate heat. One wetting of the wood suffices for the taking of twenty or thirty such impressions. Even the colour of the wood can, to some extent, be produced by varying the nature of the acid, or by using paper or calico of the desired tint. The most striking examples of nature- printing, however, are the beautiful prints of leaves, ferns, and woods which form the bases of some highly- illustrated books. Nautilus Propeller is a substitute for the screw and the paddle in the propulsion of steamers. The chief inventor connected with it is Mr. Ruthven. The system has not yet (1868) come much into use, but 'its leading features are as follow : The hull of the ship is perforated in a pe- culiar way, so as to admit water into a large iron case or chamber. In this case rotates a horizontal turbine- wheel, acted upon from the steam- engine by means of a vertical shaft. The wheel is divided into compart- ments by partitions of peculiar shape ; and these compartments are always full of water. When the NEE 249 NEE steam-engines are at work, and the turbine-wheel made to rotate hori- zontally, or round a vertical axis, water is driven out at the periphery of the wheel by centrifugal force, and a new supply sucked in through the hollow axis of the wheel. The out-driven water rushes through two pipes, and escapes by two open noz- zles at the sides of the ship. These nozzles being bent backwards to- wards the stern, the water rushing from them is resisted by the water of the sea, a reaction is produced, and the ship is driven forward. The nozzles can, singly or together, be opened forward instead of rearward, and out of this arise some peculiar results not obtainable either by the paddle or the screw. The captain, by touching a handle placed easily within reach on deck, can in an in- stant open the nozzles forward in- stead of rearward, and the ship will then move astern instead of ahead ; if he opens the starboard nozzle forward and the larboard nozzle rearward, he can turn his ship ra- pidly round to the right in a circle of very small radius ; if he reverses the nozzles, an equally rapid move- ment may be made round to the left. So effective is this arrange- ment, that some engineers believe a ship might be steered as well as pro- pelled by the turbine, without the aid of any rudder ; while it is cer- tain that the ship could be stopped, if necessary, in a very short space of time by simply reversing the noz- zles. As the wheel keeps on steadily rotating in one direction, whether the ship is going ahead or astern, the engineer is not troubled with perpetual orders from the captain to back and slow the engines, &c., the control being immediately under the hand of the captain or pilot him- self. The Admiralty are trying the system on the Waterwitch, a gun- vessel of about 800 tons. Needle G-un, the equivalent of the German ziindnadelgewehr, is the breech -loading rifle which the Prus- sian army has adopted, and which wrought such disastrous effects upon theAustrians at the battle of Sadowa in 1866. Its name is derived from the fact that a kind of steel needle is employed to pierce the percussion- cap and explode the detonating com- position. The rear end of the barrel is somewhat conical, and fits into a corresponding cavity in the fore- end of the breech-piece. A needle or strong steel wire is so placed that it may be drawn back by the trigger, and fixed in a definite position ; when released it is impelled forward by a spiral spring, and made to pierce the cartridge, and explode a small cap of detonating composition placed in front of the gunpowder. The me- chanism by which all this is accom- plished is exceedingly intricate, far more so than that of the Snider- Enfield rifle. The cylinders, bolts, screws, grooves, nuts, shunt-pieces, recesses, springs, catches, notches, &c., are very numerous ; and most English military officers are of opi- nion that the complexity is likely to lead to frequent disarrangements, not always easy of repair. (See fur ther under RIFLE, RIFLING.) Needle Manufacture. The making of needles illustrates the wonderful amount of work that can be given for a small sum when the demand is enormous. The follow- ing brief sketch will show how nu- merous are the processes which a needle manufacturer, such as those who maintain the staple trade of Redditch, carries on. (i.) Cutting.the Wire. The steel wire, brought from Sheffield or Birmingham in coils, is uncoiled, and cut up into pieces long enough for two needles each : this is done with amazing rapidity by means of shears fixed up against the wall. (2.) Straightening. To straighten these small pieces, some thousands of them are collected in a heap, icated in a stove, and rolled to and ro on an iron plate by the pressure NEE 250 NET of a peculiarly-shaped tool. The pieces correct the curvatures one of another, and all come out flat. (3.) Pointing. Every piece is then pointed at both ends, because it is to make two needles. The grinder, by a peculiar management of his fingers and thumbs, contrives to hold many pieces at once against a revolving grindstone, which quickly wears away each end to a point. This is a very unhealthy employment, owing to the particles of steel-dust and stone-dust which enter the lungs; and the workmen are " said to be very regardless of precautionary m ea- sures which have been devised for their benefit. (See GRINDING.) (4.) Making the Eyes. Every piece of steel has now to have two eyes stamped and drilled in it. This is delicate work. By means of a die and counterdie, worked by a press, two grooves are stamped on each side of each piece, and two indenta- tions that mark the position of the two eyes. Then a tool containing two sharp piercers is brought smartly down by means of a press, and the piercers make two holes clean through the piece, they being of much harder steel than the needle- piece. There are other modes of making the eyes. Indeed, this is the matter to which the needle-maker directs special attention : the grooves and the eyes should be particularly smooth, and free from sharp edges ; for needles " warranted not to cut the thread" are imperatively de- manded by seamstresses. (5.) Sepa- rating and Straightening. Several pieces are threaded on two fine wires, and by a little filing and bending, they are broken into two pieces each. These pieces have, of course, the head rather rough, and require the roughness to be re- moved by filing, several being held together at once in a sort of flat vice. The needles having become a little bent by all these processes, they are rolled to and fro on a flat plate by a sort of file. (6.) Tempering and Scour- ing. The needles are brought to a red heat, plunged into cold water or oil, and then gradually heated and cooled again to bring them to the proper temper. They are next scoured, to get rid of the filmy oxide on the surface. Fifty thousand of them, or so, are wrapped in canvas coverings, with emery, oil, putty powder, and soft soap, and rolled under heavy pressure until they have rubbed each other clean, smooth, and bright. (7.) Drilling and Finish- ing. The best needles are drilled, to obtain the smoothness of eye just adverted to ; and this is done after the scouring. Every needle is ap- plied successively to an exquisitely fine drill, rotating rapidly, in such a way as to round off the edges of the eye. The points are then sharpened and polished, first on a rotating hone, then on a buff-leather wheel. Thus it will be seen that manual dexterity is the chief agent in needle- making, steam power being em- ployed only to a limited extent. The cheaper needles do not go through so many processes as are here described ; whereas " gold-eyed " needles have to go through a pro- cess of metal-gilding. It is said that Redditch produces between 20,000,000 and 30,000,000 gross of needles in a year ! The finished needles are worth about fourteen times as much as the steel wire of which they are made. Nets; Netting. The various kinds of net used by fishermen are humble imitations of the beautiful bobbin net made into lace; or ra- ther, the latter is made by improve- ments on the machinery employed in making nets. The thread is usually a twine of hemp or flax ; but jute, cotton, and other fibrous materials may be substituted. The texture differs from ordinary woven fabrics in two ways the largeness of the meshes or open spaces, and the tying of a kind of knot at every NET 251 NEW intersection of the twine. The size and the shape of the mesh, as well as the thickness of the twine, vary with the purposes to which the net is to be applied : the fisherman establishes a difference between seine, trawl, and drift nets ; the bird-catchers and the hunters of ani- mals have various kinds ; gardeners have nets with different sizes of mesh to cover their plants ; and special sorts are used in several trades. Nets are usually made by hand, with the aid of a few simple but peculiar tools. There are, however, net-making machines in use. The hemp is heckled, carded, roved, and spun into yarn or twine ; and then a netting-loom, acting somewhat on the principle of the stocking frame (see FRAMEWORK KNITTING), makes up the twine into netting by the aid of sinkers, needles, bobbins, shuttles, and other small apparatus of a curious kind. It is found that, for fishing, a net made of cotton is more durable than one made of hemp a fact not credited until experiments had made it mani- fest; and it is also proved that finer and lighter nets can be made of cotton. The introduction of ma- chinery was partly the cause, partly the consequence, of this change of material, seeing that cotton nets can- not be well made by hand. About half a century ago Mr. Paterson, of Musselburgh, invented a net-loom, to supplement, if not to supersede, hand-work. For many years the invention was not of much value, seeing that the hand manufacture supplied the current demand. By the year 1839, however, he had eighteen looms at work in a factory employing about fifty persons ; and a few years afterwards the machine was further improved so as to tie knots in the nets as tight as those tied by hand. The trade is now an extensive one in Scotland, employ- ing thirteen or fourteen factories of considerable size. That of Messrs. Stuart at Musselburgh (the succes- sors to Mr. Paterson) is the principal. It is a fine structure, occupying an oblong square of four acres. Besides a long array of spinning machines for cotton and hemp, there are 200 net looms, each twice as large as an ordinary weaver's loom, being 6 to 8 feet in width by 6 feet high. Their appearance and their action are midway in character between weaving looms and stocking frames. Hitherto they have been worked by manual power, the application of steam power to them not having yet been effected. Herring nets are the principal kind made to supply the vast herring fisheries of the North ; but there are also other kinds for salmon, mackerel, pilchard, and sprat fishing. Hemp still retains its superiority for the heavier and stronger nets ; but some of the cotton herring nets are so fine that a net of 60 yards, with 300 meshes in the width, will only weigh 12 Ibs. It is stated in the Scotsman newspaper that 600 looms and 2,000 persons are now engaged in this wholly modern manufacture in Scotland. Newspaper Addressing:. The Americans have devised a very in- genious mode of addressing news- papers for transmission through the post. The machinery consists of two parts the engraved block and a printing apparatus, (i.) The ad- dress block is made by stamping into a piece of wood, endwise of the grain, the requisite letters and figures, which are arranged radially on an axis, and which can, by rotating the axis, be brought into position as required. When the letter or figure has been turned downwards, a treadle moves the block, and the stamp is impressed into it. Scarcely a minute is requisite to produce an address block. (2.) The engraved blocks are then, by means of a me- tallic clip, fastened at the back and strung on a tape. A belt of such blocks is inked by an ordinary ink- NIC 252 NIT ing roller, and then placed on a very simple printing press. Each in turn is then imprinted on a separate newspaper, and belt after belt put on the machine, until the issue is directed to the whole of the sub- scribers. Such an apparatus saves much time when the same sub- scribers are sent to day after day. Nickel, one of the metals, is sometimes found in the native state, but generally in combination with other substances. When pure, it is about 8 times as heavy as water. It is of a greyish-white colour, mag- netic, ductile, malleable, requires a high heat for melting, and resists acids very well. Nickel is found combined with arsenic in kupfer- nickel, nickel glance, and -white nickel, with sulphur and antimony in nickel stibine, with antimony alone in antimonial nickel, with sul- phur in nickel pyrites, with sulphur and iron in nickeliferous pyrites, and with iron in most meteoric stones. The metal is obtained from many of these ores by smelting and other processes. Nickel is not much used in the arts by itself, but is serviceable in many of its com- binations. Its alloys take part in the preparation of 'some of those white metals which are now highly favoured by those who seek for the brilliancy of silver without the cost. (See ALLOY ; WHITE METAL.) Niello Work, much practised some centuries ago, is a peculiar mode of ornamenting surfaces of metal. The surface is engraved (more deeply than for printing), usually on silver, and the lines are filled up with a black or coloured composition of silver, copper, lead, sulphur, and borax. The dark colours thus inlaid, contrasting with the bright surface of the silver, produce an effect bearing some analogy to that of a print from a copper plate. The art, after being long neglected, was revived a few years ago by Wagner, a silversmith at Berlin. Nitrates; Nitric Acid. The corroding liquid which the alchemists called aquafortis, and which is still known by that name in commerce and manufactures, is called by che- mists nitric acid. It is one of five different compounds of nitrogen and oxygen. To produce it, nitre, or nitrate of potash, is mixed with sul- phuric acid, and exposed to the ac- tion of heat in iron or earthenware retorts ; the sulphuric acid combines with the potash to form sulphate of potash, leaving the nitric acid of the nitre separated. The nitric acid or aquafortis in common use con- tains one-half or two-thirds water. It is used for an immense number of purposes in the arts, to act on metals, earths, fibres, and chemicals in a great variety of ways. Nitric acid combines with other substances to form nitrates, which have still more direct practical value than even the acid itself. Nitrate of potash constitutes nitre. (See the next article.) It is especially in combina- tion with metallic oxides that the acid forms the most useful nitrates. Nitre. Nitre and Saltpetre are two names for the same substance, the latter implying" stone salt," or " salt of stone." The chemical name is nitrate of potash, the sub- stance being a combination of nitric acid with potash. It may be either ob- tained naturally or produced artifi- cially. (I.) The Natural Mode. Nitre is often produced on the surface of the ground in hot climates, after the rainy season, by the action of heat and moisture on the alkaline constituents of the soil. The white efflorescence, with a little earth un- der it, is scraped up and dissolved in water, partly evaporated by the sun's heat, and further evaporated by fire. The result appears as crystals of nitre. Such a mode of obtaining the substance is largely adopted in Bengal, Egypt, and Hungary. In some regions nitre forms spontaneously on the walls NIT 253 NOR and roofs of limestone caverns, de- rived from the felspar of the rock. When scraped off, with fragments of felspar intermixed, the substance is pounded, mixed with wood ashes, and steeped in water ; sediment falls to the bottom and an alkaline lye remains, which, when evapo- rated, yields crude nitre. This is the chief source of nitre in Ceylon, and in some other countries where limestone caves exist. (2.) The Artifi- cial Mode. One plan of producing nitre is the following : Animal re- fuse of any kind is mixed with old mortar or lime and earth, and built up into heaps. Being watered fre- quently with alkaline liquor, the nitre gradually separates from the other substances, the nitric acid being developed from the animal refuse, and the potash from the mor- tar. A crude lye is obtained, which, by boiling, skimming, depositing, and evaporating, yields crude nitre. This plan, varied in detail, is fol- lowed in many continental coun- tries. The merest animal refuse and the crumbling mortar of old walls are made to yield a substance with- out which gunpowder could hardly be manufactured. The crude nitre, as imported from India and else- where, must be deprived of many extraneous salts before it becomes pure. Rough nitre is dissolved in water, heated, skimmed, and clari- fied by the addition of a little gela- tine or glue ; the clarified liquor is boiled, and set aside to crystallise in shallow copper vessels. The crys- stals are washed in two or three waters, and eventually become nearly pure nitrate of potash, nitre, or salt- petre. The enormous quantity of 1,400,000 cwt. of nitre was imported in 1867. Nitro-G-lycerine, G-lonoine, or Blasting- Oil, is a liquid which has recently attracted a great deal of attention, partly on account of its usefulness in the arts, partly on ac- count of the terrible accidents that have been occasioned by it. It is made by the mutual action of nitric and sulphuric acid on glycerine. Nitro-glycerine is an oily yellowish liquid which explodes, under various circumstances of heat and percus- sion, with inconceivable violence ; and it is the production of this ex- plosion by accident that has led to such dreadful disasters to persons, buildings, and ships. When care- fully used, nitro-glycerine has an explosive power far exceeding that of any gunpowder; and hence its employment as a blasting oil in mines, quarries, and tunnels ; but much has yet to be ascertained be- fore it can be transported, ware- housed, and used with safety. Nitro-Muriatic Acid obtained from the alchemists the name of Aqua Regia, by which it is still often known. Norwegian Stove. Apart alto- gether from the ingenious contri- vances noticed under STOVE, and incidentally mentioned in other arti- cles, there is one called the Norwe- gian stove which is very peculiar in its character ; being either a stove or a refrigerator according to the mode in which it is used. It attracted great attention at the Paris Exhi- bition in 1867, and also in connec- tion with the Food Committee of the Society of Arts. The action of the apparatus depends upon the non- conducting properties of some sub- stances compared with others in relation to heat. Cow-hair is the substance selected in this instance, possibly because it can be purchased at a cheap price, and is at the same time very heat-resisting. A well- made square wooden chest or case, from a foot cube to a yard cube, or more, is completely lined with a cushion made of cow-hair thick, soft, and well packed ; and the in- side of the cover is similarly lined. The interior is arranged for one or more tin saucepans, round or square ; and the cushions are so exactly NUM 254 NUM shaped that, when the saucepans are inserted, the cushions press closely against them on every part top, bottom, and sides. There is no fire, flue, draught, or pipe of any kind. The apparatus does not supply heat ; it only keeps in heat derived from some other source. It is not ap- plicable to roasting, baking, frying, or broiling; it applies to boiling, stewing, steaming, simmering, and other modes of cooking with water and steam. The meat, pudding, soup, &c., is made to boil in one of the saucepans on an ordinary fire ; and then, as soon as at a full boiling temperature, is put into the chest, where the saucepan nestles down into its recess among the cushions. The lid being closely covered down, time does the rest. The cow-hair cushions form an almost impenetrable barrier to the passage of the heat outwards; the contents of the saucepan remain nearly at a boiling heat for several hours ; and the food becomes tho- roughly cooked. Such, at least, is the theory; and the investigations above alluded to lend much support to it. To whatever extent this result is obtained, a saving of fuel, time, and trouble is an obvious accompa- niment. When used as a refrige- rator, substances or beverages at a cooler temperature than that of the room are placed in the chest. As in the former case the cow-hair cushions stayed the exit of heat from within, xo in this latter case do they retard the entrance of warmth from with- out, and the inside of the chest long continues to be cooler than the out- side. This ingenious apparatus is the invention of M. Sorensen. Number Printing- is a name that may conveniently be given to that process whereby successive numbers are printed on successive copies of the same ticket, or succes- sive pages of the same book. Bank notes and railway tickets exhibit two familiar forms of this kind of print- ng. In bank notes the general contents of the note are printed irst, and the number afterwards. The numbering machine was in- vented by Bramah, and greatly im- aroved by Oldham. There is a se- ries of discs, or rowels, face to face on the same axis ; each rowel can be made to rotate separately, or each can be made to act upon its neighbour at certain points of the process ; and each has all the digits standing out as types upon its edge. After printing a number, say 13,724, the apparatus makes a slight shift and presents 13,725 for the next printing; and so on until 13,729, when the next shift alters two of the digits, giving to the next arrange- ment the form 13,730. The simple principle being once understood, its application can be carried out to any extent. Shaw's page-numbering machine and Edmonston's railway- ticket machine produce similar re- sults by mechanism analogous in principle, though differing in detail. The more complete of these ma- chines have self-acting apparatus for inking the types, as is now familiar to every one in the booking-offices of the several railway companies, where each ticket is numbered and dated by means of the small machine at the elbow of the clerk. Water- low's machine for these purposes is very efficient. The French have not been wanting in attention to this subject. M. Trouillet's numera- teur micanique is a very ingenious machine for numbering coupons, railway certificates, or bank notes, as likewise for paging account-books, or numbering bales or packages of merchandise. It consists of a rowel- formed circle, on the points of which are cut in steel the ten numerals ; it turns on an axis which may hold from two to six of these rowels. The figures that are to move are left free ; those that are stationary are fixed by a screw at the side. The figure is changed by the action of a NUT 255 OAT small lever, the pressure of which turns the rowel so as to bring the next figure in its place, and at the same time inks itself from a small inking apparatus fixed above the figures. "With six rowels numbers i to 999,999 may be impressed, the first of the series appearing as 000,001. The instrument may also be used dry for stamping anything where colour is not needed, but only an impression ; or with common marking-ink for stamping bales of goods or wooden packing-cases. The instrument here described is for hand use. There is another variety for press use, executing the addi- tional process of printing labels requiring dates, such as those of the month and year. (See also NEWS- PAPER ADDRESSING.) Nut Making*. Besides the sim- pler and more usual hand-process, there is for the making of nuts and bolts a large establishment at Bir- mingham in which such articles are made, in enormous quantity and with great rapidity, by machinery. The pig-iron, after being puddled and rolled in the usual manner, is placed in a reverbcratory furnace, rolled to the required size, and placed in a nut-making machine. Here a sufficient length of iron is cut off, forced into a die-box {of quadrangular or any other required form), and punched simultaneously from both sides while under pres- sure. The process is so conducted that the metal is solidified while cutting the hole ; the hole is made exactly central, as well as true and smooth, the angles are made regular and equal, and the size is rigorously defined and maintained. The ma- chine can make from fifty to eighty nuts per minute. For making bolts and screw-bolts a different arrange- ment of machinery is adopted. Nutmeg- is the kernel of the nut- meg tree of tropical climates. This fruit, at the proper season, has a fleshy exterior, which is often pre- served as a sweetmeat ; then a yel- lowish-red film, which constitutes mace; and then the kernel itself, the nutmeg. From it can be ob- tained a yellowish fat called oil of mace, and a colourless essential oil of nutmeg. 37o,ooolbs. of nutmeg were imported in 1867. Nut Oil, expressed mostly from walnuts and hazel nuts, being clear and colourless, is usefully employed in making varnishes and some kinds of paint. o. Oak. The timber of this tree is used for numerous purposes in ship- building, carpentry, turnery, cooper- age, and other arts, owing to its strength and durability. Pollard oak presents a beautiful grain, fit for veneering and polishing. Oak bark is one of the most useful tanning in- gredients. (See BARK; TANNING.) The cups and acorns of one species constitute the tanning and dyeing substance iialonia; another yields flip %ai'.-nut ; another kermes ; an- other cork indeed, the oak gene- rally may be ranked among the most valuable of trees. Oakum consists of old tarred ropes, untwisted and separated into a kind of rough hemp. It is very useful in caulking, or closing up the seams and crevices in ships. Oats do not go through so great a variety of manufacturing processes as barley, seeing that malting is almost confined to the latter. The grinding into oatmeal is managed nearly in the same way as the grind- ing of wheat into flour. One par- ticular preparation is noticed under GROATS. The Scotch sowans is made by the action of barley-water upon the husk of oats. The Russians OBS 256 OIL distil their quass from oats ; and British distillers mix it in small quan- tity with barley and malt in making spirits. Obsidian is a variously-coloured mineral, hard, brittle, and having a peculiar vitreous lustre. The lapi- dary, by careful management, can fashion it into boxes, buttons, and other trinkets. Rude nations used to employ this mineral instead of flint for arrow and spear heads. Ochre is a general name for many kinds of earth or clay im- pregnated with iron. The greater the quantity of iron, the deeper generally the tint. Terra di Sienna, red chalk, Armenian bole, stone ochre, yellow ochre, are names of various kinds used in the arts. In Cornwall the ferruginous mud left from the washing of tin and copper ores is sometimes further washed to procure a useful ochre from it. Near Torbay, iron exists in many of the rocks around the coast, and near it a kind of ochre which makes excel- lent paint ; this, under the name of iron-paint, is used in painting iron and wooden sheds at the Govern- ment arsenals. The reddle em- ployed in marking sheep is made from ochre. Odometer, Perambulator, or Road-measurer, is an instrument for measuring distances in roads and streets. There is a wheel of such a di- ameter that the circumference exactly equals half a pole V 3 feet) . While this wheel is rolling along the ground, teeth in the axle work into other teeth in the end of an iron rod ; the rod is made to rotate ; this rotation is communicated to a train of wheels ; the wheels govern the in- dex hand of a dial ; and this dial is thus made to record the number of miles and poles which the wheel has rolled over. A handle connected with the iron rod is used to propel the instrument. The train of wheels and the graduations on the dial may be adapted to any other kind of land measure instead of miles and poles. A smaller kind of road- measurer, to be worn in the waist- coat pocket, is described under PEDOMETER. An adaptation of the odometer is sometimes applied to a carriage while travelling ; the rota- tion of the axle of one of the wheels being made to communicate motion to a hand or hands moving round a dial. Oil. Among many ways of classi- fying oils is into fat and essential ; the former having a greasy con- sistency, the latter going off readily into vapour. They are found in the animal, vegetable, and mineral kingdoms, under a great variety of forms. They vary from the con- sistence of a thin liquid to that of a solid as dense as lard. Most of the animal oils are obtained from cel- lular membrane, vegetable from seeds, and mineral from some kind of shale. Some are drying oils, soon drying in the open air to a kind of resinous varnish; whereas greasy oils show very little tendency to do so. The oils are too numerous to be named here ; but the more use- ful varieties obtained from vegetable sources are linseed, nut, poppy, hemp seed, rape seed, olive, almond, castor, cacao, cocoa (these two are quite different), palm, cotton seed, and colza. The sperm, train, cod, pilchard, seal, shark, porpoise, and dolphin oils are productions of the animal kingdom ; while petroleum, paraffine, naphtha, &c., occur in the mineral kingdom. Most of the principal oils are noticed under their proper headings. Many kinds of oil require to be rejined for use ; this is done by the application of va- rious agents steam, charcoal, bark, bleaching liquid, caustic soda, &c., according to their nature. For paint- ing, varnishing, and many other trades the distinction into fat and drying is of considerable impor- tance. The chief fat oils are olive, almond, ben, beech, rape, cacao, OIL 257 OIL cocoa, palm, colza, radish ; the chief drying oils are linseed, nut, poppy, hemp, castor, cotton-seed. These are irrespective of the fish oils, which are fat and greasy. Taken in the aggregate, our imports of oil are very large. In 1867 they amounted to 22,000 tuns petroleum, 16,000 tuns whale oil, 20,000 tuns olive oil, 17,000 tuns seed oil, 812,000 cwt. palm oil, 150,000 cwt. turpentine oil, &c. Our export of seed oil amounted to 7,000,000 gallons. Oil Cake. (See LINSEED, LIN- SEED OIL; OIL MILL.) Oil Furnace, or Oil-lamp Fur- nace, mostly used in scientific che- mistry, is a small and compact ar- rangement whereby camphine, rock oil, or almost any kind of oil or spirit can be employed to produce a hot flame without much regard to luminosity. Various forms have been devised by Deville, Griffin, &c. Griffin's oil-lamp furnace, com- prising a wick holder, an oil reser- voir, and a fire-clay furnace, will not only bring metals to a white heat, but will fairly melt a pound of iron in a quarter of an hour. Oil G-as. In countries where oily seeds are plentiful and coal dear, it may be more profitable to make gas from the former than the latter. All kinds of oil, and refuse fat and resin of every description, are equally available. Large establishments for this purpose have been erected in England ; but the cheapness of coal has rendered these oil-gas works a failure. In otherrespects, oilisbetter, as it contains more illuminating ele- ments and fewer impurities than coal. At present, India knows nothing of gas-lighting, except at Calcutta and Bombay ; but little more is wanting than good gas-machinery for the profitable making of oil-gas in that vast country generally. Wherever oil-gas can usefully be manufac- tured, the deviations from coal-gas making are not very numerous. The oil flows in a continuous stream from a tank into iron retorts, which sometimes also contain pieces of brick to increase the heating surface. The slow red heat of the retort, decomposing the oil, sends off the products as oil-gas and tar-gas ; the tar-gas condenses in a neighbouring vessel ; while the oil-gas passes into a purifier, where lime takes away the impurities from it. The purified gas finally passes into a gasometer or gasholder, ready to be employed in the usual way. (See GAS LIGHT- ING.) An estimate for an oil-gas work, published by Mr. Cola, is made applicable, to a very wide range of magnitude ; from one only large enough to supply a single house, to one applicable for a whole town. Supposing there to be only gas wanted enough to supply six burners, three hours per evening on an average (sufficient for Indian evenings, with the early habits of the people), the cost would be ^26 for retorts, purifier, gasholder, &c. For one that would supply thirty burners, gz IQO burners, ^230 ; 500 burners, ^780; 2,000 burners, 2"i,920. The larger the plant of machinery, the less the cost per burner. One gallon of linseed oil will yield about 80 cubic feet of gas ; and each burner will consume i cubic feet per hour. Oil Mill. The various seed oils are pressed and purified by the /ol- io wing means : (i.) Screening. The seeds, laid in a heap, are lifted by a self-acting elevator, and conveyed in small baskets to a flat screen or sifter, to shake out impurities. (2.) Crushing. When thus sifted, the seeds descend between two heavy iron rollers revolving in opposite directions. Some fruits and nuts require a rasping action instead of crushing. (3.) Grinding, The crushed seeds are laid upon a bed, and then ground by the action of two heavy edge-stones, which both rotate on their axes and revolve in a circle. OIL 258 OLD Minor adjustments insure the equal grinding of the whole mass, which gradually becomes an oily paste or dough. (4.) Heating. If the oil is to be hot-drawn, the paste is placed in a vessel heated by steam, and exposed to the action of stirrers or revolving arms, which keep it in motion. (5.) Bagging. The paste, whether heated or not, is transferred to bags made of strong cloth ; and these are placed between other bags called hairs, made of horsehair covered with lea- ther. These hairs are expensive to buy in the first instance, and soon wear out by the heavy pressure to which they are subjected. (6.) Pressing. The bags of seeds are placed in piles, in such a way that the action of the hydraulic press can be brought to bear upon them. This pressure is enormous, amounting sometimes to 300 tons. Under its influence the oil first separates .from the paste, then passes through the cloth bags, then through the hair bags, and then through pipes into a cistern. (7.) Stripping. After the paste has been pressed dry by the expulsion of the oil, the bags are stripped off from it, and there remains a kind of board or plank of oil-cake, available to cattle-feeders. According to the kind of seed, fruit, or nut, and the degree of refining required in the oil, some of the processes may be modified, or others added to the number ; but the general routine is as is here indicated. Olive oil is obtained by pressing the fruit of the olive in a very simple way; that which first comes over constitutes the finest salad oil ; the remainder is of somewhat coarser quality. Linseed oil is largely used in mak- ing paints, varnishes, and printers' ink. Rape-seed oil, obtained from the cole or colza plant, is, when purified, the best of all lubricators for locomotives and fine machinery ; and its consumption now is very large, especially by railway -com- panies. Cotton-seed oil is used in soap-making, the residue or cake as cattle food, and the husk and attached fibre in paper-making. On account of the cost of freight, this kind of oil can hardly be made profitably except in the cotton countries. Cocoa-nut oil, obtained from the fruit, is now used to aii enormous extent in making candles and soap, especially by Price's Patent Candle Company. Mr. Cola, in giving an estimate for an oil-mill suitable for India, includes an ele- vator, crushing rollers, rasping ma- chine (for cocoa-nuts), edge-stones for grinding, heating kettle, stirrers, cloth bags, hair bags, two hydraulic presses, four oil cisterns, force-pump, steam-engine, boiler, and mill gear- ing ; the cost of the whole being ^2,500. The estimate is, that in a working day of ten hours, 9,360 quarters of Bombay linseed would by such machinery be made to yield 564 tuns of oil and 1,174 tons of oil-cake. Old Metal. This, so far from being merely a colloquial term, is a technical designation of great im- portance in the metal trade. Not only is it a wise economy to utilise the materials of worn-out vessels, &c., but the metal is often in a really improved condition for various manufacturing purposes, mellower and more homogeneous than newly- prepared metal. Old horse-shoes, old hoops, old railings, old wire, often make capital scrap-iron, when melted up again with new. At Bir- mingham old metal generally de- notes some kind of mixture in which copper takes part, and Mr. Timmins states that the brass and sheathing manufacturers look out regularly for a supply of this old metal as an ad- dition to the new. Sheathing-sheets, bolts, nails, locomotive-engine tubes, marine-engine tubes, filings, turn- ings, old copper and brass picked up by hawkers and gatherers all are welcome, whether they contain cop- per, zinc, or tin. The almost incre- OLE 259 OPI dible quantity of 8,000 tons of these worn-out metal goods finds its way to the busy town annually. Most of the smaller firms make their brass of this old metal revivified with new copper. Old ship-sheathing is sys- tematically taken in exchange for new, at its ascertained value, and thus the same particle of copper may perchance go towards the sheathing of a dozen ships in succes- sion. Worn-out locomotive tubes make good brass, with new copper added. Oleine. (See STEARINE.) Olibanum is the gum resin of an Oriental tree, and is nearly the same thing as Frankincense (which see). Olive Oil. Olive oil, chiefly pro- duced from the pericarp of the fruit (not from the seed), is noticed under OIL. The finest kind constitutes salad oil. The coarser kinds are used in making Castile soap, other kinds of soap, candles, and in pre- paring the wool for wooUen manu- factures. The olives used as incen- tives to digestion are the fruit, picked before being quite ripe, and pickled. Olive wood and olive root are valued by cabinet and trinket- box makers for the beautiful grain and the polish they take. The bark, leaves, and flowers are useful for a few purposes in the arts. Onyx is a kind of medium be- tween agate and chalcedony, having something the appearance of each ; and sardonyx is a variety of it. All varieties of this mineral have been much sought after as a material for cameos and other small delicate ornaments. What has, in recent years, been called Algerine onyx, or onyx marble, is a stalagmitic marble, or transparent limestone, very beautifully varied in colour, and quarried in pieces sufficiently large to make statues, chimney-pieces, &c. Opal is a mineral something like quartz in composition, but much more beautiful in appearance, exhi- biting a great play of brilliant colours. Lapidaries work it up into settings for rings and brooches, and the larger pieces into boxes and other orna- mental articles. Special examples of opal, large and beautiful, com- mand a very high price. Jewellers speak of a matchless opal in the imperial collection at Vienna, 5 inches by 2^- inches. Operameter, a counter or mea- surer of the quantity of work done by a machine, is employed under many different forms. Walker's ap- paratus for this purpose has a train of toothed wheels and pinions en- closed in a box ; index hands, like those of a clock, are attached to the central arbor, while a dial-plate is marked with graduations which these hands will measure. Project- ing from the hinder part of the box is a shaft, which may readily be placed in connection with the work- ing parts of a gig-mill, shearing ma- chine, or other machine. The shaft is thus made to rotate so long as the machine is working, and the number of revolutions of the shaft recorded on the dial shows the number of revolutions which the machine itself has made. This particular form of apparatus was made for use chiefly in the woollen-cloth manufacture. An analogous apparatus called a counter is used in many other fac- tories, and in various establishments where steam-engines are employed, to record the number of revolutions of a main shaft, or the strokes of a piston. Opium is the hardened juice ob- tained from the capsule of the white poppy. Incisions are made in the poppy-heads while growing, and the juice flows out in small quan- tities. Very little more is done to it before sending it to market, where it is sold in the forms of cakes, sticks, and balls, for eating and for smoking. Morphine, narcotine, codeine, meconine, and other sub- stances are obtained from opium by OPT 260 ORE chemical processes. In Europe opium is chiefly used as a source from which to obtain the alkaloids just named ; but in Asia the con- sumption for eating and smoking is enormous. India has been known to export opium in one year, after serving the home demand, to the value of ^"10,000,000, chiefly to China. Optical Glass. The glass re- quired by the makers of high-class telescopes, microscopes, prisms, &c., is the best which art can produce ; seeing that any flaw, streak, or spot becomes magnified as a defect in the using of the instrument. Scrupulous choice of ingredients, and delicate processes of making, are indispensable. If the ingre- dients are not well mixed and dif- fused, the glass will have a higher optical power at one part than at another; if any of the grains of sand or flint are imperfectly fused, they produce spots ; if one side of the melting-pot be hotter than another, the glass will be unequal in quality ; if the cooling be either too quick or too slow, irregularities of other kinds arise. Hence a piece of really perfect glass, large enough to make the object-lens for an equa- torial telescope or a transit instru- ment, is valued very highly. Glass for ordinary instruments, with loper cent, increase of oxide of lead, is, after careful mixing and melting, blown into cylinders, which are cut open into slabs about 14 inches by 10, and half an inch or so in thick- ness ; the optician cuts off pieces from this slab to grind into lenses of the sizes needed. A very perfect, but not very durable, optical glass is made of a combined silicate and borate of lead, according to a plan suggested by Dollond, Herschel, Faraday, and Roget, at the invita- tion of the Astronomical Society. Numerous researches have been made by Guinand, Fraunhofer, Merz, Bontemps, Daguet, and others on the Continent, and by Messrs. Chance, of Birmingham, to produce optical glass of high qua- lity. Discs of large size have been displayed at the various Interna- tional Exhibitions of 1851, 1855, 1862, and 1867, some as large as 29 inches diameter, with results so far satisfactory as to encourage further experiments. It may here be men- tioned that, as the object-glasses of achromatic telescopes are made by a combination of flint-glass and crown-glass lenses, those two kinds of glass must be equally studied to attain good results. Orange, irrespectively of its ordi- nary use as a fresh fruit, and as a material for marmalade and for can- died peel, is caused by chemical processes to yield essence de petit grain, oil of neroli, oil of sweet orange, oil of bitter orange, rosoglio oil, and other essences and liqueurs. Orange wood is used as a veneer for small cabinet-work. Orchil, called also Archil and Cudbear, is a dye-drug for produc- ing violet and crimson tints, made by chemically treating various lichens found on the sea-shore. Ore Dressing:. This comprises such preparatory operations in Me- tallurgy (which see) as do not require the application of heat or the use of furnaces. In some metals, such as iron, the product would not pay the cost of much dressing; while in others, such as copper, the value of the metal offers encourage- ment to a good series of preparatory processes. Again, some metals are easily separated from the gangue (stony impurities) of the ore during smelting ; whereas others cannot be so without previous dressing. Hence ore-dressing assumes different forms under different circumstances. In the first place, the miner usually se- parates the coarser and most cum- brous gangue while in the mine, in order not to send up to the surface too large quantity of useless matter. ORE 261 ORG- Then, on the ground above, women and children, by means of hammers, separate the ore into three heaps useless gangue, ore rich and clean enough to go at once to the smelter, and ore of an intermediate kind requiring dressing. The last-named class is that to which the processes of ore-dressing are chiefly applied ; and these vary with the nature of the metal, (i.) For Copper the frag- ments of selected ore are crushed under large cast-iron cylinders, and screened in a large wire-gauze cy- linder, until brought to rather a fine condition. There is a considerable degree of subdivision observed by the copper ore-dressers of Devon and Cornwall the ore being di- vided into spoiling stuff, picking rough, and shaft small, according to the size of the pieces ; and into frills, dradge, and halvans, accord- ing to the richness of the ore in metal. Foreign copper ores usually fetch a higher price at Swansea than English ores, partly because they are more thoroughly dressed. (2.) For Lead the ore is first sorted into three kinds, called knockings, riddlings, and fell, according to the size of the pieces ; and these re- quire different degrees of crushing and pulverising. The ore is next passed between a pair of fluted rollers, and then down an inclined plane to a pah* of smooth iron cy- linders ; the cylinders finish the crushing which the rollers began. The cylinders maybe brought nearer or further apart, according as need requires. Another pair of cylin- ders is used for the inferior kinds of ore called chats. Sometimes the gangue is too hard to yield to the rollers, and then the stamping-mill is employed. (3.) For Tin the amount of dressing required is much greater than for copper or lead. The large pieces of ore are broken moderately small by hammers, and the pieces too poor to be worth smelting are picked out and thrown aside. The good pieces are then crushed by a stamp- ing-mill. This consists of twenty to fifty wooden beams called stamp- ers, 10 feet long by 8 inches square, shod at the lower end with i^ to 4 cwt. of cast-iron ; the stampers are worked up and down by cogs in a large wheel moved either by water power or steam power. The ore, placed beneath, is crushed by the repeated blows of these formidable stampers, an abundant supply of water being furnished to aid the process. The ore passes through gratings into troughs, where it is separated into slime, crop, and leav- ings, according to the size. Further separation is made between qua- lities and sizes by numerous .pro- cesses of washing, shaking, and sifting, called huddling, tozing, chimming, dilluing, tying, jigging, trunking, and racking', the result of this is, that a very large propor- tion of stony and earthy matter is driven away, leaving the ore rich in tin. Sometimes a partial roasting is necessary during this chain of operations ; but most usually all the processes are cold. So much more is done to tin ore than to copper ore by the dressing, that dressed tin ore is seven times as rich in metal as dressed copper ore ; whereas in the undressed state the copper is the richer of the two. The ore-dress- ing (if it may be so called) of gold is described under GOLD WASHING. The chief operations of smelting, after the ores have been dressed, are treated under COPPER, IRON, LEAD, TIN, ZINC, &c. Organ, Church. The organ, admittedly the noblest of musical instruments, involves much more scientific action than the pianoforte. The latter strikes a stretched string with a hammer; the former blows a column of air through a pipe, thereby adding the philosophy of pneumatics to that of mechanics. During more than a thousand years the church organ has been under- ORG 2t>2 ORG going incessant improvement, until at length it has become a mass of me- chanism at once formidable and deli- cate. ( I .) The Pipes. All the sounds of an organ are produced by or in pipes. Some of these pipes are of wood, and square in section ; some are of metal, and cylindrical. The upper end of some is open, while that of others is closed with a plug called a tompion. The lower end of some has an opening or mouth; that of others an apparatus called a reed. All these differences affect both the pitch and the quality of the sound emitted. The longer the pipe, the deeper the tone ; a closed pipe emits a sound an octave lower than an open pipe of the same length ; a mouth-pipe produces the sound in some such way as that of a flute is produced, whereas the reed- pipe has a vibrating tongue like a clarionet. The pipes vary from 6 inches to 32 feet in length, and the kind of wood or metal employed determines whether the sound will be brilliant or mellow. (2.) The Stops. This is rather an inconvenient name for the thing denoted. A stop is a set of pipes, from low notes gra- duating through medium up to high notes, all having the same quality of tone. This quality may vary with wood and metal pipes, square and cylindrical pipes, open and closed pipes, mouth and reed pipes ; but the quality is the same for all the pipes in the same stop. Sometimes the stop is denoted by certain figures, sometimes by words sup- posed to be descriptive of the quality of sound such as flute, oboe, cla- rionet, trumpet, bassoon, cremona, dulcinea, vox celeste, vox humana, diapason, principal, clarion, cornet, &c. (3.) The Keys. If there were only one pipe to each key, the keyboard would be as simple as that of the pianoforte ; but the several stops or sets of' pipes require two or more keyboards for their management. Technically, the name organ is given to a keyboard and the particular stops which it governs ; thus there are the great organ, the choir or- gan, the pedal organ, and the swell organ, or swell, each governing a certain number of stops. By pulling out or thrusting in a small handle or plunger, any one stop may be put into or out of play. The number of keyboards as well as the number of stops depends on the magnitude and completeness of the instrument. The pedal keys are pressed by the feet, the manual by the hands. (4.) The Bellows. The pipes "speak or sound by the keys opening a communication between them and a space filled with compressed air. The bellows are very varied in ac- tion, but usually bear some kind of resemblance to large forge-bellows, with lever-boards, elastic leather sides, and a nozzle or mouth-piece. Manual power forces air by means of the bellows into a wind-chest, where the air is condensed in pro- portion to the pressure applied. When the keys are pressed down, they open certain passages in the wind-chest, and the air, rushing out, passes into and through the pipes, enabling each to give forth its pro- per sound. In very large organs, additional power is needed to force in an adequate supply of wind. The organ belonging to the Oratory at Brompton has 15 stops in the great organ, 15 in the swell organ, 17 in the choir organ, 12 in the pedal organ, and 15 under various other names, or 75 in all. One of the stops, the sesquialtera in the great organ, has no less than 232 pipes, and there are 3, 544 pipes altogether. There are, however, much larger organs than this in existence, judged by the number of stops and pipes. There are also some highly sci- entific contrivances for working the bellows. The application of elec- tricity to the organ is now occu- pying attention. Many advantages would often result if the keyboard ORG 263 OTT could be placed at pleasure in posi- tions distant from the serried ranks of pipes, above or below them, be- fore or behind them, to the right or the left, &c. So long as the con- nection is wholly mechanical, this cannot very easily be accomplished ; but there is some ground for believ- ing that this difficulty will gradually be obviated. As electricity will convey messages to great distances through a submarine cable or a land wire, so may the organ-player's wishes be conveyed from the key- board to the pipes. A church organ has been made, in which a cable of insulated wires is placed in con- nection at one end with the key- board, and at the other with the pipes, each wire transmitting the musical message from one key to one pipe. The hope of the inventor is, that all the delicate lights and shades of organ-playing may be pre- served by this mechanism ; but this is a matter which can only be deter- mined by long experience. Organ, Mechanical. Poor as it is in a musical sense, the barrel organ is really more complex than a keyed organ of equal size, owing to the nicety required in studding the barrel. There is no keyboard. There is a barrel, the surface of which is studded with metal pins or wooden studs. These pins, con- fused as they appear, are arranged strictly in accordance with some particular melody. When the barrel revolves, the pins strike against cer- tain levers, which open air-passages leading to the pipes, and thus the pipes are made to sound. Some of the barrels are rotated by turning a handle, some by spring clock-work ; and this power, whichever it may be, is also made available for work- ing the bellows. In most barrel organs, the barrel is large enough to accommodate more than one tune ; in this case, a catch or slide puts into action just that set of pins or studs which belong to the tune to be played, and places the others temporarily out of gear. Certain large and powerful instruments, under the names of apollonicon, orchestrion, &c., are in principle barrel organs, consisting of pipes made to speak by the action of studded ban-els ; their merit lies in the great number and variety of the stops. A musical snuff-box may be regarded as a small barrel organ with clock-work action instead of a handle, and vibrating tongues in- stead of pipes. (See HARMONIUM.) Orgransine. (See SILK MANU- FACTURE.) Orgeat is a composition of al- monds, barley-water, loaf sugar, and orange-flower water, usually taken as a syrup to flavour beverages. Orleans is one of the many names given to the stuff goods manufac- tured in the Bradford and Halifax district. It is not all worsted, having usually a cotton warp. Ormolu. (See BRASS; MOSAIC GOLD.) Orpiment. (See ARSENIC.) Orris Boot, the root-stock of a plant growing in the South of Eu- rope, is used for scenting oils, hair- powder, tooth-powder, and for dis- tilling into what is erroneously called essence of -violets. Osiers, or Willows, are the sub- stance of which the generality of baskets are made. There are many kinds, such as the Kentish, the French, the grey, the Spanish, the Welsh willow, &c. The plants are cut down at a proper age, split, peeled, &c. (See BASKET MAK- [NG.) Otto. The otto or attar of roses is a very powerful and valuable essential oil obtained from the petals of the rose. It is only some species that will yield it, and only some petals in those species. The steep- ing, distilling, cooling, and other manufacturing processes are all very carefully conducted chiefly in India. The real otto is a light yel- OVE 264 low crystalline substance, obtained as a sediment from the chemica treatment of the rose petals. It is extremely costly, owing to the large number of roses necessary to pro duce a small quantity of it. The perfume being very intense, a minute quantity will scent a large amoun of oils, pomades, washes, &c. ; anc hence otto of roses is an impor- tant agent in the hands of the per- fumer. Oven. The relation which an oven bears to a STOVE, a FURNACE, or a KILN is not always very defi- nite, the four terms being used rather indiscriminately. (See the above- named headings.) The term oven is sometimes given to a complete cook- ing apparatus, such as that which is now often supplied to the army. Captain Grant, of the Royal En- gineers, has contrived barrack and camp ovens, in which baking and boiling can be carried on with very little complexity of apparatus, and a small consumption of fuel. In June, 1868, Messrs. Perkins tested the capability of their travelling oven, in which the soup, meat, bread, &c., go through the boiling and baking processes while on the march; the hope is that troops may have a chance of hot dinners even when they have very limited time for bivouac or camping. The oven employed in Dauglish's sys- tem of Bread Making (which see) is divided into several sections, with apparatus for separately regulating the heat of each. There are glazed openings at intervals, through which the progress of the baking may be watched from without. One end of the oven is so arranged that the loaves may be readily removed into the receiving chambers or sections ; and the mouth is provided with a sliding door, so arranged as to close when the hood or cover of the re- ceiving chamber is open. Within the oven is an endless chain of plates of sheet-iron, periodically moved a OXA short distance after the closing of the hood and the opening of the sliding door. An oven employed for 2 Ib. aerated loaves is 50 feet long by 10 feet wide, and divided into five sections, each having its own fire- place, flue, and sight-window. At the further end of the oven is a descending passage closed by a weighted valve ; this valve opens by the pressure of the baked loaves against it, and then the oven empties itself. By these arrangements the baking goes on with much uni- formity ; while an increased brown- ing of the crust of the loaves may at any time be insured by raising the heat in one of the sections of the oven. Ox. The services which oxen, and indeed cattle generally, render to the arts, are so many that they can hardly be named. The hides, the hair, the horns, the teeth, the bones, the blood, the tallow, the marrow, the intestines, the gall, the hoofs, the tendons all are eagerly bought up, and some of them are made the bases of large branches of manu- facture, after the butcher has been upplied with that which is the pri- mary object of the grazier's atten- :ion, viz., the meat or flesh. (See HAIR MANUFACTURES, HORN MANUFACTURES, LEATHER, TAL- LOW, &c.) Oxalic Acid exists in a large number of vegetable substances, rom which it can be obtained by he action of nitric acid or potash in various ways. The plan mostly adopted in England is that of Messrs. Dale, of Manchester, viz., making oxalic acid from sawdust >y the action of soda, potash, sul- )huric acid, and lime. Oxalic acid s a colourless crystal, easily soluble n water. It is extensively employed n calico-printing, wool -dyeing, leaching straw plait, &c. The alts which it forms with various mses are called oxalates, many of which are employed in the arts, OXI 265 PAD especially oxalate of potash, the so- called salt of lemons. Oxides. As oxygen is the most abundant of all natural elements, and the one which enters into the greatest number of combinations with others, it follows almost of ne- cessity that oxides (combinations of oxygen with one other element) are a jet connected with a steam-boiler. Steam at a pressure of 40 Ibs. per square inch rushes from the jet down the pipe, carrying with it a very large quantity of air ; this air, accu- mulating in the false bottom, rushes up through the perforations, and mixes with the solution, rapidly oxi- dating substances which may be the most numerous of binary com- I in the water. The heat communi- pounds. To name their multifarious I cated to the solution by the steam uses in the arts would be to go | greatly facilitates the process. It is through nearly the whole range of j considered that this method may be man's industry. Under the names | useful in making soda water and of the principal metals, alkalies, | other aerated waters, and in many earths, &c., the oxides are briefly noticed. When another simple substance takes up oxygen, it is generally (but not always) said to be oxidised. Oxidising; Oxidation. The oxidising of metals is brought about by a number of natural agencies, combining the metal chemically with a certain definite quantity of oxygen, and the same thing is done artificially in a wide range of the manufactur- ing arts. Not only the metals, but sulphur, phosphorus, carbon, &c., may be oxidised by various natural and artificial means. Mr. Har- greaves has recently devised a mode of oxidating bodies dissolved in water by the action of air alone. This is an example of oxidation, as distinguished from oxidising. The liquid to be oxidated is put into a vessel with a double bottom, the upper surface of which is perforated with small holes. A pipe ascends from the false bottom to a little above the top of the vessel ; over the open upper end of this pipe is chemical manufactures. Oxyhydrog-en Light. (See DRUMMOND LIGHT.) Oyster Opener. A curious ap- paratus for opening oysters has been invented by Mr. Napier. The front edge of the oyster (while the shell is tightly closed in the usual way over the fish) is placed on a cutter fixed to a frame or bed-plate ; the flat shell is placed undermost, and the edge projecting a little beyond the cutter. A lever handle is then pressed downwards, so as to cut away the outer edges of the top and bottom shells. The oyster is next removed from its place, and rested upon two blades ; one of these blades is fixed to the frame, and the other attached to the lever handle ; they have thin outer edges, suited for readily pass- ing into the opening between the shells ; an india-rubber spring tends to keep the two blades together. When the lever handle is a second time pressed down, the shells will be separated, and the oyster opened, by the separating of the blades. P. Packfong- is one of the numerous family of -white alloys. The Chinese are credited with the introduction of it. Packfong consists of 5 copper and 2 arsenic, melted in presence 1 of a little common salt. Paddle Wheel. The paddle used to propel a canoe may be regarded as the beginning of a paddle-wheel, seeing that such a wheel consists of many paddles, which, by the rota- tion of the wheel, dip successively PAD 266 PAL into the water. There were mecha- nical boats before there were any steamboats, propelled by paddle- wheels which were rotated by a winch handle. In its modern form the paddle-wheel has many radii or spokes, the outer ends of which support an equal number of floats, boards, or paddles ; and it is the forcible passage of these boards through the water which causes the vessel, by reaction, to advance in the opposite direction. A good deal of power is wasted by the par- ticular position of each paddle when it enters and leaves the water ; and ship-builders now often endeavour to lessen this loss by a contrivance like that of feathering an oar. An oars- man gives a twist to his oar of such kind that the plane of the blade is nearly vertical at the instant of entering and quitting the water. A similar effect is produced in the movement of the paddle-wheel by the aid of an eccentric arrange- ment of rods and hinges. Large paddle-wheels are now made wholly of wrought-iron. The mightiest paddle-wheels ever made are those of the Great Eastern, 56 feet dia- meter, 13 feet deep, and having 30 radii and paddles. Paddy is the name given in India to rice before the husk has been removed. Paging: Machine. (See NUM- BER PRINTING.) Paint; Painting. The paints, pigments, or colours used by. oil- painters, water-colour painters, ena- mel - painters, porcelain - painters, house-painters, &c., comprise an immense range of substances from the animal, vegetable, and mineral kingdom chiefly mineral ; and these are mixed to the proper consistency with various liquids, such as varnish, oil, turpentine, size, vinegar, gum, water, &c. The chief pigments, and the chief vehicles for mixing with them,, 'are treated under their proper headings. For the principal instrument of the painter's craft see BRUSH. The terms priming, flatting, grounding, graining, &c., refer to various modes adopted by the house-painter in applying his pigments. Palimpsest involves a curious bit of practical chemistry. A palimp- sest is a piece of parchment or vellum which has been twice written on, the first writing having been rubbed out to make room for the second. The object seems to have been to use up old material as a means of saving expense. Historians and archaeolo- gists often attach more importance to what was originally written than to that which succeeded it ; and the deciphering of old palimpsests has become a regular study. The primary writing was more or less removed by washing, scraping with a knife, or rubbing with pumice, according to the kind of ink used ; but the moderns have found that, by the use of an infusion of gall, dilute muriatic acid, hot oil, and other liquids, they can manage to decipher the primary writing under or between the lines of the secondary. Palissy "Ware, if genuine, was the veritable product of the enthu- siastic potter after whom it was- named. Employed in an entirely different kind of trade, he laboured for many years to discover the secret of some particular kind of enamel ware which had struck his attention ; and his trials and diffi- culties during this search render the aiography of his life a very interest- ng one. The wares which he eventually produced were remarkable "or elegance in form, and for the fidelity with which leaves and other natural objects were imitated in his mythological and allegorical deco- rations. Palmetto. The broad leaves of he Palmyra palm are largely used as a material for hats, mats, and :hatch. PAL 267 PAP Palms ; Palm Oil. The various kinds of palm tree subserve an immense number of uses in the arts. The flexible stems of some supply canes and rattans. One kind of stem yields sago. The leaves are applied to almost numberless uses, some being so vast as 50 feet long by 8 feet broad, with very substantial stalks and veins. The date and the cocoa-nut are the fruit of palms. Toddy and jaggery are obtained from the sap. Palm oil and cocoa-nut oil are only two among the kinds of oil yielded, some by the pulp, some by the kernel of the fruit. Among the useful fibres of the palm may be reckoned coir, or cocoa-nut fibre. The coquilla nut, the vegetable-ivory nut, the betel nut, palm wax all come from one or other of the palms. Some of the wood is hard and beautiful; and the leaf-stalks are often large and strong enough to be used for carpentry purposes. Panorama. Mechanically con- sidered, a panorama is a circular picture which requires a particular arrangement of carpentry to enable many persons to see it at one time. Mr. Barker and Mr. Burford have been the chief artists in this depart- ment of skill. It requires much tact in determining what shall be the diameter of the circle, the height of the wall on which the picture is painted, the distance of the spectator from the picture, his height from the ground, and the mode of admitting light. Panoramas were once greatly in favour, but they have gone com- paratively out of fashion ; the beauti- ful panoramas of London at the Colosseum are now (1868) closed; while Burford's Panorama build- ing, in Leicester Square, has been converted into a Roman Catholic chapel. Moving panoramas have been exhibited, in which a picture of immense length, instead of being exhibited on a circular wall, is un- coiled from one roller to another, and rendered visible in the portion between the rollers. The Diorama was a picture in which transmitted light was combined with reflected light to produce very beautiful effects; there was also mechanism by which the spectators were moved from one of two pictures to the other, by the revolving motion of the platform or gallery on which they were seated. The Cosmorama is a superior kind of puppet-show, in which the pictures are seen through a focalising lens. Pantagrapn, or Pantograph, is an instrument for enlarging or reducing the copy of a drawing, map, or any other design. A tracer is passed over every line of the original ; a pencil at the same time marks every line on the copy ; and according to the mode in which cer- tain levers are hinged together, the copy may be made larger or smaller than the original, or exactly equal to it. Paper. From very early times men employed some kind of thin sub- stance on which to write. The sub- stance might be of animal, vegetable, or mineral origin ; the writing imple- ment might be a pen, pencil, or style of any kind ; and the vehicle might be a solid or a liquid ink. In- deed, the variations in all these par- ticulars have been almost intermin- able. At one time on stone, at an- other on metal, at others on brick, on sheep-skins or goat-skins, on leaves of the papyrus and other kinds of tree, on bark, onrind allhavehad their day. The Chinese appear to have been the first to make paper ; that is, vegetable substance reduced to a pulp and flattened into thin sheets. They were not restricted to one substance ; cotton, hemp, rice straw, bamboo bark, mulberry stalk, all w-ere called into requisition ; these ingenious people having found out the way to reduce the pulp to a film by a process the very same in principle (though wonderfully modi- fied in detail) as that whicft is how employed in Europe. So far as can PAP 268 PAP be known, paper was first made in Europe in the fourteenth century, and in England in the time of Queen Elizabeth. Paper was always made by hand till the beginning of the present century, since which date the paper machine has gradually been brought to a high degree of perfection. The materials for paper patented in England, and in most instances tried for a limited time, have been exceedingly numerous. They comprise literally hundreds of kinds of leaf, thistle, stalk, moss, shoot, husk, heath, tendril, cane, bark, root, pith, reed, rush, grass, lichen, weed, nettle, and other plants or portions of plants ; together with spent tan, wood shavings, asbestos, fern, hair, peat, wool, leather, and other substances not easily brought under any par- ticular classification. In every case the substance is brought to a pulp by various degrees of steeping and boiling; the pulp is reduced to the state of a thin film by the drain- ing action of a square sieve or wire screen ; and the film thus pro- duced is dried into a sheet of paper. It is found that nothing equals rags, especially those of linen, as a ma- terial for paper. Straw, however, being cheap'er than linen rags, at- tempts are constantly being made to extend its use in paper-making; and, indeed, much straw paper is now made for writing, printing, and wrapping purposes ; but the ac- tual cost of working is nearly as great, owing to the necessary use of chemicals to act upon the straw pulp. (See STRAW PAPER.) Es- parto, a Spanish grass, is much used for the penny newspapers. (See ESPARTO.) There is a large use of hemp and old rope for coarse brown paper. A good deal of mine- ral substance is now mixed with the fibre, such as white clay, gypsum, and calcined flint. A small portion improves the paper by filling up pores; but a large percentage is clearly a mere matter of cheapness. Our imports of foreign-made paper in 1867 amounted to 326,000 cwt. The export of British (and foreign) was smaller 190,000 cwt. For manufacturing processes see ES- PARTO ; PAPER MAKING; STRAW PAPER. Paper Boxes. The manufacture of paper, or rather cardboard, boxes gives rise to a considerable branch of trade. The French excel in it. A few years ago there were 4,000 per- sons thus engaged in Paris alone; and now the number must be much greater. There are six classes of articles thus made under the collec- tive name of cartonnage boxes, (i.) Highly-finished boxes for containing artificial flowers, velvets, ribbons, satins, silks, trimmings, wedding trousseaux, &c. (2.) Boxes to con- tain the countless varieties of con- fectionery and bonbons. (3.) Boxes for various kinds of trinkets. (4.) Boxes for perfumery, fans, and gloves. (5.) Large strong boxes for shawls, ribbons, &c., for ex- portation. (6.) Boxes for pills, wafers, and small articles of various kinds. Until about twenty years ago or so, English manufacturers and shopkeepers were accustomed to wrap their wares in paper more generally than they do at present ; cardboard box-making has since then been introduced from France, or at least encouraged as a home manufacture ; and now vast numbers of such boxes are made in London, and in most of the great centres of textile manufacture, where the chief demand exists. The cutting, shap- ing, pasting, &c., comprise many ingenious labour - saving contriv- ances. Paper Folding-. Many inge- nious machines have been invented for folding sheets of paper, for books and newspapers, for enve- lopes, for paper bags, &c. One of these contrivances, by Mr. Black, folds printed sheets into the 8vo., PAP 269 PAP I2mo., or 241110. forms with pre- cision and rapidity. Another ma- chine, of Swiss invention, both folds and stitches. The sheets, put upon a bed or table, are seized by a knife which has aup-and-down motion ; it takes hold of each sheet lengthwise in the centre, draws it through a slit in the table, and thus makes the first fold. The knife re- turns instantly ; a second knife at- tacks the sheet, and folds it at right angles to the first fold ; and so on a third or even a fourth time. This folding may or may not be followed by a process of stitching in the same machine. Another contrivance has an ingenious air-sucking apparatus, which takes the sheets one by one from off the pile under a horizontal folding-knife, and folds them. Some of the machines fasten as well as fold. Adorno's cigarette machine cuts, wraps, and folds the paper in which the tobacco is enclosed ; an endless roll of paper, and a certain quantity of tobacco, are supplied at one end of the machine, and finished cigarettes emerge at the other. Tay- lor's lamp-shade machine folds, or rather moulds, flat circular discs of paper into hemispherical shades. Youngman's paper-bag machine will make 2,000 or 3,000 bags per hour, folding, pasting, cutting, and de- livering without hand-labour. De- vinck's machine for wrapping cakes of chocolate is another ingenious contrivance. (See also ENVELOPE MACHINE.) Paper Hang-ings are made of coarse, cheap paper, printed with distemper colours. They used to be produced by Stencilling (which see), but they are now printed from blocks. The blocks have a syca- more or pear-tree face, with* a pop- lar or pine-wood backing ; the de- vice is so engraved upon them as to be printed by the surface-plan ; they are as wide as the strip of pa- per, and there are as many different blocks as there are colours in the pattern. The colours are mostly mineral, diluted to the proper de- gree, usually with liquid size, to which a little starch is sometimes added. An equable layer of ground colour is laid on with a hand-brush, or a rotating brushing machine ; and sometimes also the paper is passed between polishing rollers. Then the printing commences. The colour is brushed upon a drum or sieve of calf-skin ; a block is dabbed face downwards upon it ; a layer of colour is taken up ; this layer is transferred to the paper, which is laid down flat upon a long bench. Over and over again is this done, until the whole paper is co- vered with a device in one colour. Four pegs at the corners of the blocks assist the printer in keeping register, to make the successive printings exactly match edge to edge. Then another colour is brushed upon the drums, and transferred to the paper in the same way ; and so on until all the colours have been applied. Flock paper has a layer of powdered or ground wool applied in certain parts of the pattern, by sifting it upon a wet varnish of lin- seed oil, litharge, and white-lead. The flock sometimes receives grada- tions of tint by painting with a pen- cil or brush. Gold paper, or gold added to colour, is done by print- ing that part of the pattern with gold size, and laying gold leaf or gold powder on it. Satin paper has a glazed surface, usually effected before the printing, but sometimes afterwards ; the paper is prepared with fine gypsum, then with French chalk, and then rubbed with a bur- nishing brush. Washable paper hangings are coated with some kind of varnish. Paper-hangings are now often printed by the cylinder mo^ chine, as in calico-printing: much more rapidly than by blocks, but not so well. The arsenic used in green colours for paper-hangings has lately been found injurious to the health PAP 270 PAP of persons living in rooms so pa- pered. Paper Making-. We will sup- pose the best machinery to be em- ployed, and linen rags to be the chief material. The processes occur in the following routine : (i.) Rag Cutting. The cutting table has a surface of coarse wire netting, and bears a large upright knife in the middle. A woman takes the pieces of rag one by one, and scrapes them along the edge of the knife, by which they are easily severed. When cut into pieces of pretty uniform size, she drops them into three or four different cells or compartments according to the quality. (2.) Rag Dusting. All rags are dusty when brought to the mill those from Ire- land, Italy, and the East much more so than those of England, Holland, and Germany (an indirect testimony to the relative cleanliness of different nations). They are therefore put into the rag-dusting machine, where a revolving shaft with radiating spikes tosses them about, and the dust falls out, either at the lower end of the inclined cylinder, or through the wire gauze of which the cylinder is made. (3.) Rag Boiling. Here the dirtiness of different rags is more distinctly shown than in dusting. They are boiled in alkaline water, in a vessel heated by steam, and so kept ro- tating that all parts may be equally acted upon. (4.) Pulping and Wash- ing. One more cleansing process. The rags in the rag-engine are not only exposed to a continuous stream of water, but are at the same time subjected to the action of a series of knives fixed to a roller, by which they are converted into a pulp of small fragments called half -stuff. (5.) Bleaching. The half-stuff is then bleached with chloride of lime in a vessel called the Heaching-vat ; or sometimes the bleaching is done at the same time as the washing and pulping. (6.) Beating. The bleached half-stuff is next transferred to the beating-engine, where, being sub- jected to the action of toothed and edged rollers revolving 150 times a minute, it is reduced still finer, and takes the nam* of pulp or stuff. (7.) Hand Paper-making. All paper used to be made by hand, and some kinds are still so made. The stuff is transferred to a -vat, and kept warm. A mould and deckel are used to make it into paper. The mould is a shallow wooden frame, somewhat larger than the sheet of paper to be made; it has wires tightly stretched across it, very close together, and these wires produce the slight markings, or apparent edges and hollows, in foolscap and some other kinds of paper. The deckel is a slight frame, outside as large as the mould, inside as large as the paper. The mould, with the deckel placed on it, is dipped in the stuff, a quantity of which is taken up on it. The water drains through the wires, and the thicker part of the pulp or stuff remains as a thin film upon them. The deckel being removed, the film is turned out of the mould upon a felt or piece of woollen cloth ; then another film, then another felt, and so on. The films, which we may call sheets of paper when thus far made, are pressed, dried, sized, dried again, examined, and finished. To make large sheets by this method is diffi- cult and somewhat laborious work. (8.) Machine Paper-making. At length we come to the beautiful paper-making machine, which, by the successive inventions of Four- drinier, Dickenson, Bryan and Don- kin, &c., has become one of the most perfect automatic machines known in the arts. It performs many distinct processes, each of which has its own particular part of the apparatus. The pulp falls into a stuff chest, where it is diluted with water and kept constantly stirred. Falling into a trough below, PAP 271 PAP it parts from all knots or impurities, which are unable to pass through very small holes in a brass plate. The stuff flows upon an endless cloth or apron of wire gauze, so fine as to have 3,000 to 5,000 meshes in a square inch. The apron has a vibrating motion given to it by rollers underneath ; and this causes the stuff to distribute itself in an equable layer, and to shake off su- perfluous water. The stuff, tra- velling along as the apron travels, passes over a box or recess in which an air-pump produces a partial vacuum ; and this vacuum sucks out nearly all the remaining moisture, leaving the stuff virtually in the state of a dry film. The film passes between rollers which com- press and solidify it, and at the same time give it what is called the water- mark. Travelling along an endless felt, the film receives further pres- sure from other rollers. The paper (which the film has now become) dips into a vessel of size, which coats it on both sides. It passes over a steam-heated cylinder, which thoroughly dries the size. Either in the same machine, or in another which acts end to end with it, the paper, which at present is in the form of an endless sheet coiled round a cylinder, is cut up into sheets by a reciprocating knife, all the sheets being of one size, determined by the adjustment of the machine. Finally, the sheets fall down and arrange themselves in a regular pile upon a table. So beautifully are all these successive processes managed, that each comes into operation exactly at the proper instant. The sub- stance never stops in its progress ; it enters as liquid half-stuff at one end of the machine, and it quits the other end in a few minutes in the form of a pile of dry sheets of white paper. (9.) Finishing. The sheets of paper, thus produced, are counted into quires of twenty- four each, and the quires into reams of twenty each. Either liot pressure or cold pressure gives a certain de- gree of smoothness and polish to them. The machines employed will make paper from 54 to 102 inches wide ; the latter width accounts for the great size of some of the printed sheets which are now published. A 72-inch machine will make about 8 tons of paper per week, of medium quality and at a medium speed of working. The kinds of paper are various printing, 'writing, wrap- ping, cartridge, tissue, blotting, fil- tering, lithographic, copying, trac- ing, tinted, toned, &c. There are also technical names for the sizes of the sheets into which the paper is made, such v&pot, foolscap, post, copy, crown, demy, royal, imperial, at Las, columbier, elephant, antiquarian, &c. It is stated by Mr. Cola that the machinery for a paper-mill, hav- ing one paper-making machine, will cost about j7, 800. The rag-chop- ping, rope-cutting, rag-dusting, rag- boiling, pulping, washing, bleach- ing, and heating machines, with the accessory mechanism, are set down at ^"2,800 ; the complex and admir- able paper-making machine, for making paper 72 inches wide, with its stuff chests, agitators, pulp regu- lators, rollers, wire gauze, air-pumps, vacuum boxes, pressing rollers, shaking apparatus, drying cylinders, sizing apparatus, calendering rol- lers, cutting apparatus, &c., ^"2,000; the steam-engines, boilers, mill gear- ing, and numerons minor acces- sories, ^"5,000. In a machine 54 inches wide, four miles of paper can be made in a day; and it is supposed that 3,000 to 4,000 miles a day are the average production of the paper- mills of the United Kingdom. The first paper-mill, supplied with ma- chinery of the most modern and approved kind, established in Aus- tralia perhaps the first in the southern hemisphere was one at Yarra Yarra, in Victoria, early in 1868 ; the machinery, weighing 500 PAP 272 PAR tons, was made by Messrs. Bertram, of Edinburgh. Papier Mache is paper brought to the state of pulp before being moulded into various ornamental forms. In one mode of conducting the manufacture, waste paper of any kind is soaked in water, worked up into a pulp, and pressed between dies. In another mode, sheets of paper are glued one upon another, on a model of the proper shape, until a considerable thickness is obtained, the paper being dried by heat after each layer. The paper is of a porous but tough kind, and is saturated with a solution of flour and glue. In a third method, sheets of brown paper are glued one upon another, and pressed into shape by means of a metal mould. In a fourth mode, sheets of thick millboard, cast from the pulp, are heavily pressed between rollers. All the articles re- quire a certain amount of trimming and finishing by hand. Various kinds of adornment are produced by means of paint, varnish, gold, bronze powder, mother-of-pearl, &c. ; and a very large manufacture is carried on, in Birmingham, of papier-mach^ trays, tables, chairs, screens, workboxes, albums, paper- cases, portfolios, &c. ; in London, of architectural and picture-frame ornaments. A stronger and lighter substitute for papier-mache, called carton-pi'rre, is made of paper- pulp, whiting, and glue. This is mostly used for architectural orna- ments. Papin's Digester. (See DI- GESTER.) Papyrus was the material for much of the paper used by the ancients. (See PAPER.) It was a kind of sedge with long leaves ; and the paper was made of many thick- nesses of the thin pellicle of the stem, cemented into a sheet of any size. Any real ancient writings on papyrus, constituting the rolls known as papyri, are highly valued by his- torical critics, on account of their trustworthiness as documentary evi- dence : the writing was done with a kind of reed, dipped in red or black ink. The ancient Egyptians were accustomed to make cordage, sandals, boxes, and even boats, of the papyrus. Parachute. (See BALLOON.) Paraffine, when pure, is a fine, white, crystalline substance, resem- bling spermaceti. It is obtained from peat, coal-tar, bituminous coal, wax, &c., by various chemical pro- cesses, especially from Boghead cannel coal. It is the most beau- tiful of all substances for candles, rivalling both wax and sperma- cetti. Paraffine oil is a product of the distillation of the coal just named ; when . further treated, it separates into paraffine and an oil very useful for lubricating ma- chinery. The relation between pa- raffine and other hydrocarbons is noticed under NAPHTHA. Paramatta is a light twilled fabric, having a cotton warp and a merino wool weft. Parchment is sheep-skin pre- pared in a particular way. When the wool has been removed, the skin is steeped in lime-water to loosen the fat. It is then stretched tightly with strings in a frame called a herse, and scraped with a double-edged, double- handled knife ; this removes all flesh, fat, dirt, &c. It is then rubbed with pumice-stone, after being sprinkled with finely-powdered chalk or quicklime. The scraping and rubbing are repeated, with some change in the ingredients, until the skin (now parchment) has become hard, smooth, clean, nearly white, and fit to write on. Some parch- ment, for bookbinding, is dyed green by means of verdigris, cream of tartar, and nitric acid. If parch- ment is made of kid, calf, or dead- born lamb skin, it is called vellum. The stout parchment for drums is made of wolf, ass, or calf sldn ; PAR 273 PAS while parchment for battledores is made of ass-skin, and for sieves of he-goat skin. Parchment, Vegetable. (See VEGETABLE PARCHMENT.) Parian is the name given to a beautiful substance now used for statuettes and small busts. It differs from ordinary English porcelain chiefly in containing soft felspar in- stead of Cornish stone. A small percentage of oxide gives that deli- cate cream-coloured tint which dis- tinguishes Parian. The substance is not pressed into form, or worked with the fingers ; but the Parian, as a creamy liquid, is poured into a mould. As it shrinks greatly during the baking, the artist has to exer- cise much skill in arranging that the size and form should be accommo- dated to the shrinking. The small busts and statuettes in what is called biscuit, or unglazed white ware, are not equal in appearance to those of Parian ; they have not the same warmth of tint, softness of outline, or translucency of surface. Parquetry is the name given to a material for flooring and panel- ling, made up of several pieces of oak or some other kind of wood, disposed according to some parti- cular pattern. If two or more kinds of wood are used, the differences in colour and grain develop the pat- tern very distinctly ; if only one kind, the pattern is produced by plac- ing the grain of the wood in different directions. Sometimes parquetry is veneered, but more usually the pieces are about an inch thick, and are used as flooring. The examples sent from the Continent to our two f^reat Exhibitions in 1851 and 1862 had much to do with the establish- ment of a taste for this kind of flooring in England. Widely dif- ferent as they are in the scale of operations, the Tunhridge-ware or- naments (such as those made by Messrs. Nye at Tunbridge Wells) have something in them of the marquetry and parquetry kind, con- sisting as they do of pieces of wood of different colours, cut to pattern, and inlaid one in the other. Partition. A wooden partition may be regarded in some sense as a floor placed upon its edge ; for the upright timbers or quartering in the one case bear some analogy to the joists in the other. The similarity, however, is not very great. The quarterings require the aid of trusses, ties, braces, king-posts, queen-posts. &c., according to the dimensions of the partition. And then the filling up between them is effected in different ways. Sometimes the quarterings serve merely as a back- ing to which laths may be nailed, to form a lath-and-plaster partition ; sometimes the spaces between them are filled up with brickwork, called b rick-nog gin g ; and sometimes with boards, when the partition would become a kind of panelling. Partridge Wood, derived from a Brazilian tree, is used for small cabinet-work, walking-sticks, um- brella and parasol handles, &c. It is named from a peculiar wavy pattern in the grain. Paste. There are many mean- ings given to this name in the arts, (i.) A mixture of flour and water, constituting ordinary paste, boiled or unboiled. (2.) The same with alum or resin added, to make shoe- makers' and bookbinders' paste. (3.) A mixture of bullock's blood, quick- lime, and water, forming Chinese paste, a cement for stone, pot- tery, and wood. (4.) Bees'-wax and spirits of turpentine form furniture paste, a material for polishing wood. (5.) Some or other of many different substances soft soap, rotten-stone, oxalic acid, olive oil, turpentine, emery, lard, Bath brick, &c., are combined to make polishing paste for brass, iron, pewter, and other metals. (6.) Naples or other soap, with varied perfumes, constitutes shaving paste. (7.) The glass for T PAS 274 PEA imitation gems is called paste. (8.) Various confections obtain the same name. (9.) Paste, lastly, is another name for. dough, in making pies and puddings. Pastil is a perfumed paste, which, when burned, diffuses odour in a room for incense, or as a plea- sant perfume, or for fumigation. It is composed of various ingredients, such as gum benzoin, sandal wood, cinnamon, essential oils, gum, &c., with charcoal powder to make them brown. Patchouli consists of the dried branches and leaves of a peculiar tree growing in China. It is a powerful perfume, and is useful as a preservative against insects. Pavement ; Paving- Stones. The flat or flag stones with which the foot pavements of London streets are paved are mostly obtained from Scotland those from Caithness being very hard. Slate would be the hardest of all, and magnificent flags or slabs, as much as 20 feet by 10, could be procured for this pur- pose ; but it is too costly for such a mode of employment. Thin-bedded flags, rather than cleavage-slate, are the kind of stone employed : Yorkshire flag is largely employed in this way. The Caithness flag is a particularly durable stone for pavements ; and the Earl of Caith- ness has taken out a patent for an ingenious machine for cutting and shaping this kind of stone. The carriage-ways are generally paved with granite, squared to particular shapes and sizes, in order that they may fit well together. Road-making is now regarded much more as an affair of civil engineering than it used to be : so great is the care bestowed upon the curvature of the road, the shape of the foot pavement towards the kerb, the provisions for drainage, and the making of a firm substratum of concrete under the stone. No great success has hitherto attended the substitution of iron, wood, or asphalt for stone. For the broken-stone method see MAC- ADAMISED ROADS. Peach. The peach is used in pre- paring two liquids known as peach brandy and peach water ; the one from the fruit and the other from the leaves. Peach -wood, used in dyeing and- calico-printing, is not from the same tree as the well- known fruit. Pearlash. (See POTASH.) Pearl Barley. (See BARLEY.) Pearls are secretions formed by oysters and similar fish. They are of the same substance as Mother-of- Pearl (which see), and are formed by the animal within the shell. Variations in size, in shape, in co- lour, and in iridescence give im- mense diversity to the prices of pearls in the market, and render the profits of the pearl-oyster fisher of Ceylon and the Persian Gulf very precarious. The Chinese compel the oysters to make pearls ; they force open the shell, and thrust in small round substances of any kind ; the animal, irritated by the intru- sion, covers the offending object with a kind of saliva, which con- stitutes pearl. Sometimes irregular pearls are ground into shape and polished, but more usually they un- dergo no further manipulation than drilling, for stringing into necklaces, &c. Very good pearls are some- times found in the Scotch mussel. The largest and finest pearl known belongs to Mr. Hope ; it is 4 inches in circumference. Pearls, Artificial, are made of glass beads or bulbs. The scales of the bleak, roach, dace, and other fish are soaked in water till a kind of pearly film separates from them ; this film, mixed with liquid am- monia, is injected into each bead through a small tube, giving to the glass of the bead a surprising re- semblance to pearl. Some of them are then filled up with white wax or with gum arabic. The French excel PEA 275 PEN iu this art, for they give to the glass beads all the irregularities of shape which real pearls display. The Ex- hibitions of 1862 and 1867 well illus- trated the artificial pearl manufacture. Pear Tree. The pear-tree wood, hard and fine-grained, is much used by turners and joiners ; and when dyed black and polished, it forms a substitute for ebony. Peat. Peat has not yet proved so useful in the arts as chemists believe it to be capable of becoming. It is a substance produced by the action of heat and moisture upon dead plants, and varies in consistency from a pasty mud to an earthy solid. Peat, bog, moss, turf, are names for different kinds. The uses for the substance hitherto tried are chiefly the follow- ing : (i.) The dder kinds are very serviceable as fuel in districts where coal is scarce and dear. (2.) The peat, mixed with ashes, tar, and other substances, forms one of the va- rieties of artificial fuel. (3.) Bog oak, found in some of the Irish peat bogs, is a very favourite material for black carved ornaments. (4.) Moist peat is serviceable as an antiseptic, or preservative against putrefaction. (5.) Peat produces a charcoal much valued for some kinds of iron and steel working. (6.) Chemicals of many kinds can be distilled from peat, including sulphate of am- monia, acetate of lime, wood naph- tha, and various oils. It is a ques- tion of price ; many valuable sub- stances can be obtained from peat, but experience alone can determine whether the manufacture can be profitably carried on. Pebbles, in jewellery, is a name rather indefinitely given to rounded specimens of agate, rock crystal, Sec. Lenr.es of spectacles are sometimes made of very clear rock crystal in- stead of glass, and then they are rather absurdly said to be pebbles. Pedal is a lever worked by the foot in the pianoforte, harp, organ, harmonium, &c. When the foot- lever belongs to a loom or a lathe, it is called a treadle or treddle. Pedometer, or Pace Measurer, is a kind of pocket watch for measur- ing speed in walking. It contains a train of wheels, and a chain or string fastened to a pedestrian's foot causes the train to advance one notch at each step by the elastic movement of the body. What the instrument really effects is to mea- sure the number of steps taken by the walker in a given space of time ; he must estimate the average length of his steps by some other means. A dial face denotes the number of notches that the train of wheels has advanced. In Payne's pedometer, for the waistcoat pocket, the moving of the wheel-notch depends on the jerk produced by putting the foot down at each step. An adaptation of this instrument may be applied to the wheel of a carriage. How the pedometer differs from other kinds of road-measurers is shown in ODO- METER. Pelts ; Peltry. A pelt is the dried but undressed skin of the bea- ver, musquash, nutria, and other fur -bearing animals. They are not regarded as Furs (which see) till dressed. About forty kinds of pelt or fur-skin constitute the recognised pelting trade of Great Britain. The chief among them are the following badger, bear, beaver, cat, chin- chilla, dog, elk, ermine, fitch, fox, goat, hare, kid, lamb, leopard, lion, lynx, marten, marmot, minx, monkey, musquash, nutria, otter, panther, rabbit, racoon, sable, seal, sheep, skunk, squirrel, tiger, weasel, wolf, wolverine. The reader will easily see which among these are met with in our own country. Pencils. (See BLACK-LEAD PEN- CILS ; BRUSH MAKING .) Pendulum. The use of the pendulum in science we are not concerned with in this work; but as an important part in the best kinds of clocks, the pendulum comes for PEN 276 PER notice in regard to the isochronism of its vibrations or oscillations. What the term means is this : When a pendulum of given length, sayexactly I yard, is set swinging, its swing is performed in just the same time, whether made large or small in ex- tent. If its path is longer, it travels more swiftly ; if shorter, it travels less swiftly ; the equality is not mathematically equal, but for all practical purposes the duration of the swing is equal until the pendu- lum stops altogether. Galileo dis- covered this isochronism in 1581 ; and he soon afterwards applied it as a time-measurer. Every shortening of the pendulum itself shortens the time in which each swing is made ; and there is thus afforded a means of dividing an hour into any num- ber of minute parts. Huyghens, Hooke, and Harris all greatly ad- vanced the practical application of Galileo's discovery, especially in making the swing or path of the pendulum very short, which causes the isochronism to be more nearly perfect. In 1715 Graham began the practice of enabling clocks to correct their own errors due to changes of temperature. When the weather gets warmer, a pendulum lengthens a little, and, by thus lengthening, swings more slowly. Hence the strict isochronism de- pends on equability of temperature. Graham invented a beautiful com- pensation pendulum, for self-regu- lation in this matter. He used a vessel of mercury for a bob or ball. When increasing warmth lengthens the pendulum downwards, it also increases the height of the mercurial column upwards ; and he caused these two opposite tendencies to balance each other. Harrison, in 1767, produced a still more perfect compensation or automatic adjust- ment, by making a sort of gridiron of different metals. Some metals elongate more than others with a given increase of heat, and Harrison so contrived that these inequalities should produce a compensating re- sult. Numerous other modes have been devised for correcting for vari- ations of temperature. See further under CLOCK, c. Pen Manufacture. (See QUILL PENS ; STEEL PENS.) Pepper is the fruit or berry of an East Indian tree, gathered twice a year. When these berries have been dried on mats, rubbed to re- move the spikes, and winnowed, they constitute black pepper ; when the berries are further soaked and rubbed to remove the skins, they become -white pepper : the black is the more pungent of the two. There is a great similarity in quality between these two and long pepper, Jamaica pepper, capsicum, Cayenne pepper, and grains of paradise, pro- duced from various tropical trees. We imported no less than I4,ooo,ooolbs. of pepper in 1867. Perambulator. (See ODOME- TER.) Percussion Caps. When the flint and steel gave place to \\\Q per- cussion cap (see GUN LOCK), mus- keteers utilised the explosive power of certain chemicals. Percussion caps are small copper cups, shaped something like a hat. They are made in a wonderfully quick manner out of sheet-copper by the aid of stamping machines. The inside of the cap is touched with adhesive varnish by a pencil; and the chemical powder is sprinkled on the varnish, to which it adheres. This powder is usually fulminating mercury and chlorate of potash ; but for cannon the former is re- placed by sulphuret of antimony and pounded glass. The cap is placed on a nipple over the touch- hole, and a blow with the lock- hammer explodes it. It seems strange that, notwithstanding the extent of our home manufacture, we imported 38,000,000 percussion caps in 1865. PER 277 PHO Perfumery. The animal and mineral kingdoms are resorted to by the perfumer for the delicate material? of his art ; but it is on the vegetable kingdom that he mostly depends. Flowers, leaves, stalks, shoots, husks, tendrils, seeds, bark, roots, pith, wood, sap all are acceptable to him, if he can obtain fragrant extracts out of them. Numerous processes steeping, boil- ing, fermenting, distilling, c. are employed in making the perfumes ; and numerous names are given to them when made, such as oils, essences, salts, wafers, spirits, oint- ments, pomades, pastes, gums, resins, lotions, dentifrices, powders, bal- sams, extracts, decoctions, infusions, incenses, pastils, syrups^ bouquets, and the like. Many herb and flower gardens are maintained almost wholly for the supply of the per- fumer. Several of the more im- portant ingredients and products of the art are noticed under their proper headings. Perry is made from pears in the same manner as cider from apples. (See CIDER.) Petard was in old times an iron case filled with gunpowder and com- bustibles, to blow open gates, &c., during a siege. Bags of powder are now generally used instead. Petroleum. See NAPHTHA con- cerning the nature of this liquid. There has been as much as 90 000,000 gallons of petroleum obtained from the oil veils of the United States in one year. The chief centre of the district, Oil City, was nearly de- stroyed by fire in 1868, owing to an ignition of petroleum. Pewter is an artificial compound of tin and lead, four parts of the former to one of the latter. It has a remarkable degree of softness and yet of toughness. Two other kinds, for special uses, are made (i) of tin and antimony, and (2) of tin, anti- mony, bismuth, and copper. In all the kinds tin preponderates greatly over the other metals. Mr. Yates, a Birmingham manufacturer, has re- cently made the following observa- tions on the progress of the pewter trade: "Plates and dishes, which were at one time the staple produc- tion, are now made only in small quantities for a few foreign mar- kets ; and latterly the trade has been chiefly engaged in the manu- facture of ale and beer measures, drinking cups, and other requisites for hotel purposes. A very con- siderable branch is now employed in fitting up refreshment stores with beer engines, liquor fountains, and other conveniences belonging to those establishments." In regard to the manufacture, the vessel or other articl : in pewter is cast in an iron or brass mould ; it is then placed in a lathe and turned to the pattern, size, and weight required. The finishing is done by burnishing. Be- sides the vessels and measures of various kinds for liquids, pewterers make syringes, inkstands, hot-water bottles, funnels, soup tureens, hot- water plates and dishes, spoons, music plates, polishing laps and wheels, freezing pots, jugs, basins, and (to a small extent) teapots made in one piece by casting. Phosphorus, one of the fifty or sixty simple substances, enters into a multitude of combinations useful in the arts. The cheapest mode of obtaining it is from bones, where it exists as an element in phosphate of lime, and from which it is ex- tricated by calcining, dissolving in sulphuric acid, and other processes. Pure phosphorus is a soft, flexible substance something like wax, and melts at H2Fahr. ; it is very in- flammable, and must be kept im- mersed in cold water for safeLy. It easily ignites, even with the heat of friction ; and this is one cause of the danger incident to its use. The chief employment of phospho- rus is for tipping lucifer matches. (See MATCHES.) The red or allo- PHO 278 PIA tropic phosphorus is less danger- ous for this purpose than the com- mon or amorphous. The quantity of phosphorus now used for matches amounts literally to hundreds of thousands of pounds annually, small as is the bit that tips each match. Phosphorus combines with oxygen to form phosphoric acid; this acid combines with a number of simple substances to form phosphu- rets, and with a number of bases to form phosphates. Examples of the uses of the phosphates in the arts will be found mentioned under the names of many of the metals and alkalies. The Cleveland iron ore contains phosphorus, detrimental to the metal produced ; and it is under consideration whether the selling value of the phosphorus would pay for the process of extraction. Photography. This wonderful and beautiful subject bears more relation to the sciences of optics and chemistry on the one hand, and to fine art on the other, than to ma- nufactures and the arts allied thereto. A few words as to the apparatus and the substances employed are all that need be given here. Many liquids have been brought into use which, when spread in a thin film on glass or paper, are very sensi- tive to the action of light. Chlo- ride of silver, iodide and nitrate of the same metal, nitric acid, cyanide of iron, ammonio-citrate of iron, bi- chromate of potash, iodide of starch, iodide of gold and platinum, bro- mides, albumen, collodion, are only some among these agents, either liquids or condensed vapours. There are, in fact, two classes of agents, sensitisers and developers. Those above mentioned, in various modes of combination, are sensitisers ; they produce a surface very sensitive to light when applied to paper, glass, leather, metal, or other substances. The developers finish the action which the light has begun, render- ing the picture visible ; they com- prise vapour of mercury and a large number of other agents. A camera is used to focalise the object (such as a person whose portrait is being taken) upon the sensitive surface. To print by photography is to take a negative picture on glass, and a positive picture from this on paper. The varieties which the art now dis- plays are almost inexhaustible ; and there are many engineering and manufacturing processes to which it is gradually becoming available, on account of the scrupulous accuracy with which drawings, plans, dia- grams, machines, engineering and structural works, &c., are delineated by it. Different modes of conduct- ing the processes have received a multitude of names, such as da- guerreotype, chromatype, calotype, talbotype, heliography, heliotype, carbon process, c. The making of photographic cameras and chemi- cals has developed large branches of trade. Even so far back as 1862 it was, stated that one firm alone used 500,000 eggs in a year to prepare albumenised paper for pho- tographers ! And since then an estimate has been made that ,1,000 a year is obtained for the gold and silver extracted from old waste pho- tographs. Photo-lithography. This, and photo -galvanography, photo- zincography, electro-photography, &c., are names given to new pro- cesses in which photography draws the picture, and some of the vari- ous kinds of engraving fix it on a plate. (See ELECTRO-PRINTING; ENGRAVING; PHOTOGRAPHY.) Pianoforte. Considered in re- lation to its mechanical construc- tion and action, the pianoforte is a singularly complex piece of me- chanism, owing to the number of small pieces of wood, metal, ivory, leather, &c., which are brought into mutual relation. The prede- cessors of this beautiful instrument were the clavichord, virginal, spinet, PIA 279 PIA and harpsichord. The clavichord was shaped something like a square pianoforte, with one string to each key ; the inner end of the key car- ried a small brass wedge which struck the string ; and as the string was muffled at that spot, the sound was subdued and somewhat melan- choly. The virginal, in use in the time of Queen Elizabeth, was nearly like the clavichord in shape, but the inner or hinder end of each key, in- stead of a brass wedge, carried a small apparatus called a jack, to which a quill or thorn was fixed ; and the manner in which this quill struck the string elicited a peculiar kind of' sound. The spinet was in form something like a harp laid down on its side ; it had about thirty brass wires for the lower notes, and twenty steel wires for the upper ; each wire was struck by a jack or quill. The harpsichord redoubled the power of the instruments above named by having two strings to every key ; these two were attuned in unison, and were struck with jacks and quills. The double harpsichord was still more complex, having two sets of keys and three sets of strings ; ' one key of one set struck two strings in unison, while one key of the other set struck a string tuned an octave higher. A further change was made by tuning all three strings for one note in unison ; but the striking apparatus was still a jack and quill. T&s pianoforte mainly grew out of all these by substituting a hammer for a jack and quill ; other changes there were in abundance, but this was the most important, as it af- fected the quality of every sound produced by the instrument. The hammer recoils after each blow; and the player can greatly vary the loud- ness and softness (hence the name, pianoforte, " soft and loud") of the sound by modifying the pressure with the finger on the key. It was introduced about a century and a half ago, and an incessant series of patented inventions relating to it have gradually brought it to a high degree of perfection. A square pianoforte has the keyboard in front of one side ; the strings are ranged in a horizontal layer, two to each note. The cabinet has the strings (usually two, but sometimes three, to each note) placed vertically, with the keyboard about midway of the height. The cottage is a modifica- tion of the cabinet, but with shorter strings. The oblique^?, the strings ranged obliquely instead of verti- cally. The grand has a horizontal shape, narrower at one end than the other ; the keyboard is at one end ; there are three strings to each note, and the instrument has greater power of sound than any other. The semi-grand is a shorter variety of the grand. The boudoir, piccolo, pianette, pianino, &c., are small and usually cheap varieties of the cottage pianoforte. There has been a gradual tendency to increase the range of the pianoforte from 5 to 5^, 6, 6, and 7 octaves ; and there are never less than two strings to a note. In a pianoforte every string is fastened at both ends to pegs, in such a way as to afford means for stretching it ; it passes over or rests upon bridges, the distance between which determines the length of the vibrating portion of the string. When all the strings of the largest instruments are fully stretched, the strain upon the end pegs, and con- sequently upon the frame to which they are attached, is something enormous, estimated to amount alto- gether to not less than 20,000 to 30,000 Ibs. ; hence the necessity for strongly bracing the wood and iron work of the frame. The upper or finer strings are of steel wire, the lower or thicker ones of brass wire, and some have very fine wire twisted round them, to give additional sub- stance. The sound produced by the strings is augmented by the sound- ing board, a large thin piece of fir PIA 280 PIE or pine, which strengthens or re- doubles the tone. Each key acts upon a lever, which moves a little wooden hammer covered with thick felt or leather, and this hammer strikes the string. If the sound con- tinued long after the removal of the finger from the key, it would inter- fere with the next note ; to prevent this a damper is used, a soft sub- stance of felt or leather which touches the string as the hammer quits it, and damps or chokes the sound. T wo pedals so act that one of them causes every key to strike on one string only instead of two, or on two instead of three, to lessen the sound ; while the other tempo- rarily shifts the dampers aside, so as to produce a more ringing, brilliant effect in some particular musical passages. These several bits of me- chanism give great complexity to the interior of a pianoforte, espe- cially to what is called the action; that is, all the moving parts between the keys and the strings. It might be supposed that the same key will produce the same tone by whom- soever it is pressed down ; and so it does in regard to pitch, but not in timbre or quality. Every great player has his own particular touch , or mode of pressing with the finger, and requires a peculiar action, or mechanism between the keys and the strings, to enable him to give effect to his favourite touch. Hence the numerous inventions by Erard, Broadwood, Collard, Wornum, Zeit- ter, Hopkinson, Stoddart, Tomkin- son, and other makers, to increase the delicacy of these small bits of mechanism, enabling the player to produce lights and shades of effect which in former days would have been unattainable. Lifters, buttons, stickers, dampers, hammers, ham- mer rests, hammer butts, hoppers, checks, rulers, rails, sockets, levers, notches, ties, flies, escapements, roll- ers,jacks all these names are given, by one or other of the inventors, to the numerous bits of metal, wood, leather, felt, &c., which form the ac- tion. There was a rough estimate in 1851 that about that time 23,000 pianofortes were made annually in London, at a cost of about^i, 000,000, averaging^"45 each. Ten years later there was another estimate, relating to the whole of the United King- dom ; this amounted to 78,000 pianofortes.worth nearly ^"3,000,000. There can be no doubt that, what- ever be the number made in 1868, the average price must be set down much lower than ^45 ; a rage for cheapness has affected this as many other trades. Pianoforte Wire. One of the causes which led to improvements in making steel wire was the gra- dual increase in the demand for pianoforte wire. Down to the close of the last century nearly all English pianofortes were strung with wire brought from Saxony and Bavaria ; and, indeed, no wire suitable for the best kinds was made in England until 1824. A new process of refining the steel, invented by Mr. Webster in that year, at once established the manufacture of a kind of pianoforte wire superior to any before known. Even then, however, it was not good enough. Instrument makers asked for wire " as hard as glass and as tough as leather," to bear the pe- culiar straining to which musical strings are subjected. The nearest approach to these combined quali- ties was made in 1854 by Mr. Hors- fall. He introduced the plan of hardening the wire by heating it red- hot and plunging it into water ; and afterwards, when necessary, soft- ening the article a little by passing the wire through a bath of melted lead. A great extension in the use of steel wire has resulted from this improvement. (See further under WIRE DRAWING.) Pietra Dura is one kind of Mosaic (which see), that depends on the inlaying of hard stone in a PIG 281 PIN slab of marble. These hard stones are pieces of jasper, quartz, chalce- dony, agate, catnelian, lapis lazuli, &c. As usually conducted, pietra ^#ra("hard stone") work is thus managed: A very thin film (merely a veneer) of black marble is pre- pared, and a pattern cut in it with saw and file pieces being cut out as large as the hard stones to be inserted. These stones, shaped by lapidary processes, are accurately fitted into the spaces thus prepared. After this inlaying, the slab is veneered on a thickei slab, and is then finished. All polishing is done before the inlaying ; because, if polished afterwards, the soft marble would be more worn away than the hard stone, and the surface would be uneven. One of the most beautiful things of this kind is a jewel-case belonging to the Russian royal family : the four sides and the top are covered with groups of fruit cut in pietra dura, but raised in relief instead of maintaining the ground level ; all the precious stones are selected of the proper colours to represent the several fruits. Pig-ments. (See under various colours, paints, &c.) Pilchard. The oil of this fish is useful for many purposes ; but its rank quality, and the mode in which it is obtained, limit its application. When the fish are pickled, and packed in hogsheads for exportation to the West Indies, the pressure squeezes out 3 or 4 gallons of oil from each hogshead; and this oil, with the blood and brine, is mostly sold as manure. A different process is needed if the oil is to be used for other purposes. Pile Engine. In driving heavy piles into the ground for founda- tions, &c., a rammer was formerly used, worked by the united strength of a large number of men. But a steam-engine is now employed with great effect, acting nearly in the same way as one of Nasmyth's steam hammers. The piles thus driven in are pointed and shod with iron ; but Mitchell's piles are screwed into sandy or loose soil. Pinchbeck. (See ALLOY; BRASS.) Pine. The two kinds of trees called pine and for constitute one great group, so far as their useful pro- ducts are concerned. On this point see FIR. Red pine, white pine, Wey- mouth pine, pitch pine, black pine, silver pine, Norfolk Island pine, are only some among the many names given to the timber. Ship-building, engineering, house-building, furni- ture-making, toy-making, lucifer- match making all are greatly de- pendent on these very useful kinds of timber. Pink, as a colour, is prepared for artists, painters, dyers, &c., from cochineal, carmine, Brazil wood, manganese, and other substances. Pin Manufacture. Pins are very good exemplars of the way in which the demand for trifling articles may give rise to the establishment of large and complete factories. The common white pin, sold retail at (say) 150 for a penny, may be taken as types of the whole. ( I . ) Drawing . When the brass wire comes from the wire-drawer, it is scoured in dilute acid, washed in clean water, dried, and drawn through a draw- Elate, which renders it hard and right. (2.) Pointing. The wire thus prepared is cut into lengths of 20 feet each, and then into pieces for six pins each. Each piece is pointed at both ends in a mill, comprising both a filing machine and a grind- stone ; it is cut, and two more points ground ; again cut, and again two points ground until the piece is reduced to six pointed but headless pins. (3.) Heading. Smaller and softer wire is taken, and wound spirally round a long piece of stiff wire the same diameter as the pins ; this is done by a kind of spinning-wheel. The coil is cut up into portions of PIN 282 PIP two to three turns each by travelling under the action of a cutting tool, which conies down upon it at regular intervals. Each of these bits is to form one head. A boy dips several pins into a heap of heads, and takes up one or more on each ; if more than one, the surplus are shaken off. A man then fixes each head on the blunt end of its respective pin by a blow from a small but peculiar kind of ma- chine hammer, worked by a treadle ; the pins being placed point down- wards in a steel die. (4.) Tinning. The pins, thus far made, are boiled in acid liquor, washed, and dried. They are then tinned, or coated with a film of liquid tin, to convert the brassy yellow into a brilliant white. They are laid in a copper pan, interstratified with grain tin, 6 Ibs. of tin to 8 Ibs. of pins ; water is added, heat is applied, cream of tartar is thrown in, and the whole mixture is made to boil. This, re- peated two or three times, gives a permanent coating of tin to every pin. (5.) Papering. The pins, after tinning, are dried in bran, and then papered. If sold by the ounce, they are weighed and wrapped; but in making what is called a paper of pins, a sort of crimping-iron is used to make two parallel creases in a piece of paper. A girl takes up several pins on a comb, the heads being thus brought uppermost ; and grooves in the crimping-iron guide her in sticking the pins through the creases in the paper. Many machines have been invented for doing most of the mechanical parts of pin-making in one continuous series of processes, including the formation of a solid head out of the same piece of wire as that which makes the pin itself. One such ma- chine, invented by Wright, draws the wire from a reel, thrusts out a length for one pin, cuts off this length, points it with a revolving file, and presses the blunt end into the form of a head. It is no longer correct to adduce the pin manufacture, as was formerly done, as an example of minute subdivision of labour, seeing that the processes are, one by one, coming within reach of ma- chinery. Wright's machine makes the whole pin complete. Birming- ham manufacturers, however, gene- rally prefer two machines, one for pointing and one for heading. Con- cerning the quantity of these small articles made every year in Eng- land, it is so enormous as almost to exceed belief. Mr. Aitken states that 15,000,000 pins are made every day in this country ; that they use up 2,727 Ibs. of brass wire ; and that one single Birmingham firm alone works up 336,000 Ibs. of wire annu- ally into pins. Pipe-clay. This smooth white kind of clay can easily be studied as it appears in a common tobacco pipe. The clay is mostly found in the counties of Devon and Dorset, but also in France and Belgium. Being very pure, plastic, and infusi- ble, it is used for porcelain as well as for pipes. Pipe Making-. Under the names of the principal metals, as also un- der LEAD-PIPE MAKING, notices are given of the modes of manufac- turing many kinds of tubes and pipes. The great consumption of metal pipes in this country is chiefly for conveying water and gas ; there are said to be 500,000 miles thus used, from \ inch to 4 feet bore. Large iron pipes are usually cast in the mode described under CYLINDER CASTING. Earthenware pipes are used to an enormous extent in drain- ing, from i inch to 4^ feet bore. Tubes and pipes of various kinds are made in wood, leather, gutta percha, india- rubber, and many other substances. For smoking pipes, besides the operations described under MEER- SCHAUM and TOBACCO PIPES, there are very ingenious processes for mak- ing pipe-stems. Cherry-stick pipes are made in enormous quantity in PIQ 283 PLA Austria, from a few inches to 8 feet in length : great care is bestowed upon the plants while growing, in order that the stem may be as straight and equable as possible. The Austrians also make pipe-stems of the young shoots of the Phila- delphus coronarius, remarkable for their quality of absorbing the oil of tobacco, and also for their flexibility. Elegant pipe-bowls are carved from the root of the tree-heath. The Turks make pipe-stems of cherry- tree, mock-orange, and jasmine wood, the sedond of which has great power of absorbing the tobacco oil, while from the third kind are manu- factured pipes very long, straight, and flexible. Australia produces beautifully-made pipes of sweet- scented myall wood. The brier-root pipe-bowls of France are well known. Piqu6 Work is a minute kind of inlaying with gold, silver, &c., a costly sort of buhl-work. Pis6 Work. This is a substitute for brick in the walls of cottages, cheap houses, &c. A timber fram- ing is set up, with spaces varying in size and shape according to cir- cumstances, and loam or dry earth is rammed into these spaces. Some of the frames are only temporary, serving as moulds, in which the loam is pressed and rammed down very tightly, the mould being removed when the work is finished. Pistol. (See SMALL ARMS.) Pitch. This name is given to substances derived from many dif- ferent sources. Comtnon pitch, used so largely in ships, boats, water- casks, &c., is the residue after ob- taining common tar from the roots of the pine and fir. Tar from coal and tar from bones are in like man- ner accompanied by pitch of their respective kinds, used in making asphalt for road-work, and coarse black varnish for railings and palings. Burgundy pitch is obtained from the sap that exudes from the Nor- way spruce fir ; but an imitation of it is made from turpentine, resin, palm oil, &c. Plaid is not, as is frequently sup- posed in England, the name of a material or of a pattern ; it is the name of a garment, the long shawl so extensively worn in Scotland. The material is usually wool, and the peculiar cross-bar pattern tartan. Plane. The carpenter's plane is a cutting tool so fixed in a stock of wood or iron that the edge can only take off a thin shaving. In most instances the tool, or plane-iron, is fixed at a particular angle from the vertical, and a slit in the bottom of the block determines the thickness of the shaving that can be planed off. There are grooving, moulding, surfacing, smoothing, rotating, jack, panel, trying, jointer, and other kinds of planes. The inclination of the plane-iron is called the pitch, and varies from neaidy vertical to 25 from the horizontal. For very hard and close-grained woods some of the planes act as scrapers rather than cutters. For special purposes the stock is of iron instead of wood. Plane Tree produces a kind of wood which, when of a mature age, is brown and fine-grained ; taking as it does a good polish, it is prized by cabinet-makers. Planing- Machine. (See MA- CHINE TOOLS; WOOD- WORKING MACHINES.) Plastering is the application of a layer of plaster or mortar to the surface of brick or some other mate- rial. It is, in fact, a kind of veneer- ing. Plastering also includes the making of plaster ornaments for the ceilings and cornices of rooms, &c. A plaster wall is to a wainscot wall of the old days what paper-hang- ing is to tapestry, a cheap substi- tute, (i.) Brick Plastering. When a brick wall is to be plastered, the surface of the brickwork is pur- posely left rough, to aid the adhesion of the plaster; and sometimes it is stabbed or picked to make it still PLA 284 PLA more rough. The bricks are wetted, washed with liquid plaster, and then coated with coarse stuff, a mixture of lime, sand, hair, and water, laid on with a trowel. This is followed by coatings of other plaster, varying in fineness according to the nature of the work. Fine stuff has fine white lime without hair : surfaces to be whitened or coloured receive a finer plaster than those which are to be papered, while those which are to be painted receive a plaster of fine lime and fine sand without hair. (2.) Lath and Plaster. Much wall- plasteringis doneupon wooden laths, instead of brickwork. Quarterings of timber are set up at intervals, and laths are nailed to them. These laths are of fir or of oak, and vary from to ^ inch thick ; they are ranged parallel, and nearly close together. On this surface the plaster is applied, varying in degree according to the kind of finish to be given to the wall. The rough, stuff is worked well in between the laths, to insure a good hold ; and the surface of this coat- ing is scratched over to enable the second and finer coating to adhere to it. Ceilings are usually plastered in the same way as lath-and-plaster walls,. (3.) Cornice Work. Formaking cornices or continuous mouldings of large size, a foundation is formed of laths nailed upon brackets, the brackets having a contour suitable for thepurpose. There then ensues akind of superior lath-and-plaster work, fine plaster being used, and gauges or mould-boards to maintain true- ness of surface. Mouldings of smaller size may be fashioned without the use of laths. (4.) Ornaments. Orna- ments to deck plastered ceilings, cor- nices, &c., are mostly made by cast- ing in moulds. The substance itself is not always plaster: it may be compo, a mixture of whiting, glue, and linseed oil ; or papier-mache, with a whitewash over it to prepare for a finishing coating; or carton- pierre ; or Q\en guttapercha. The mode of fastening the ornament to the groundwork varies according to position, materials, &c. Plaster of Paris. (See GYP- SUM.) Plate Glass. This is in some re- spects the most beautiful of all kinds of glass, on account of its trans- parency, colourlessness, high polish, absolute flatness, and facility of being silvered. The manufacture differs in many important particulars from that of other kinds of glass, as the following brief account will show : The melting-pots are very large, some of them holding as much as 30 cwt. of glass. When the molten mass is ready for use (see GLASS MANUFACTURE), a large copper ladle, held by a long handle, is em- ployed to lade it out from the melt- ing-pots into other pots called cis- terns, where it is allowed to fine or refine by settling, and to lower some- what in temperature. The casting- tabk then comes into use. This is made of iron, brass, or bronze, and is always as perfect a slab as the art of the metallurgist can produce beautifully even, flat, and smooth, sometimes as much as 20 feet long by ii broad, and 7 inches thick. There is a framework round this slab, which facilitates the operations. Huge tongs take the cistern out of the furnace ; a crane lifts it up, and places it in a peculiar position over one end of the table ; the slab is heated to a certain temperature ; the cistern is tilted up ; and the golden stream flows all over the table, being prevented by raised edges from running over. A large copper cylin- der then rolls to and fro, bringing the molten glass to a uniform level and thickness. When sufficiently solidified to be moved, the immense sheet of glass is pushed end on into an annealing oven, which is built close to it. When the glass is annealed, it is ready for grinding, to give smooth- ness to surfaces which are as yet somewhat rough. This is done by PLA 285 PLA rubbing one glass upon another, the upper glass being temporarily fixed to a frame, which has peculiar gyratory movements given to it by steam power. Sand and water, of three different degrees of fineness, are used to assist this grinding. The glass was half an inch thick in the first instance ; but this grinding, repeated in succession on both surfaces, greatly reduces the substance. The glass is now smooth, but dull ; it wants polishing. This is done, first by emery and water, and then by felt rubbers, applied in various ways. Sometimes plate glass is made by the cylinder method, described under SHEET GLASS, followed by grinding and polishing processes. Our home make of plate glass was, a year or two ago, estimated at 100,000 square feet weekly. For the silvering of plate-glass mirrors and looking- glasses see SILVERING MIRRORS. Plate, Gold and Silver.- The name of plate is rather an inconsist- ent one for the costly articles of gold and silver to which it is applied. The trade of a goldsmith and silver- smith combines the mechanical and the artistic in a remarkable degree. The former embraces almost all the processes known in metal manufac- tures casting, rolling, stamping, wire-drawing, tube-making, chain- making, planishing, moulding, turn- ing, drilling, filing, soldering, chas- ing, &c., with numerous finishing processes of a very delicate kind. For plated goods, in which there is a layer of silver on a substratum of less costly metal, see PLATING. All gold and silver plate, really such, is stamped at an assay office, of which there are several in the United King- dom ; and the symbols used are such as afford an official guarantee of the quality of the metal ; i.e., the num- ber of carats of fine gold or silver in a certain weight of the metal. It has been estimated that the produc- tion of real gold and silver plate in the United Kingdom reaches about ^"1,000,000 annually mostly in London. Plate Powder is made of rouge and prepared chalk, or of putty- powder and rose-pink. It is used for polishing plate and ornaments of gold and silver. Plating- is the coating of one metal with another of superior quality. The superior metal may be gold or silver ; the coating is not a mere wash, as in metal gilding or silvering, but a plate of solid metal. It is the next best material to solid standard gold and silver for costly articles of table-plate, &c., seeing that the thickness of the precious metal is greater than that which is deposited by the electro process. One of the first modes of practising this art was by applying leaves of beaten silver to the finished surfaces of articles in brass and steel, and causing the silver to adhere by a careful application of heat. Leaves of gold were applied in a somewhat similar way. Themode ofproducing the best Sheffield silver- plated goods is now, however, as follows : Copper and brass are cast into an ingot 18 inches long, 3 broad, and 1 1- thick. If to be double-plated, both sides of the ingot are filed smooth, and a plate of silver laid on each ; if to be single-plated, only one side is thus treated. The silver is very much thinner than the ingot. A saturated solution of borax is brushed in at the edges, and then the ingot is placed in a small oven heated with coke, where a temperature is main- tained just sufficient to make the silver fuse down upon the copper, but without allowing the latter to penetrate through and discolour the former. The compound ingot thus made is cleaned, rolled between cylinders to the required thickness, annealed frequently between the suc- cessive rollings, steeped in hot dilute sulphuric acid, and finally scoured with fine sand. The sheets thus produced have a layer of silver pro- portionate to the thickness of silver PLA 286 PLU originally applied to the ingot ; they are silvered on one side only, if for articles of which only one surface is to be visible ; but if otherwise, double- plated sheets are used. Ingots of solid silver can be plated with gold by a modification of the same kind of process. The sheets of metal thus prepared are wrought up into orna- mental forms by various processes of stamping, swaging, chasing, re- pousse, work, c., such as are de- scribed under the appropriate head- ings. Plated work of all kinds, however, is being very extensively supplanted by the more rapid and economical art of Electro Metallurgy (which see). Platinum is one of the most intractable of all metals, and forms the centre of a remarkable group, which comprises also palladium, iridium, ruthenium, rhodium, and osmium. When pure, it is the heaviest metal, and consequently the heaviest substance, hitherto disco- vered, being twenty-one times as heavy as water, and nearly twice as heavy as lead ; it is about as hard as copper, about as ductile as iron, may be beaten out into very thin leaves, may be welded at a red heat, cannot be melted in the fiercest forge, re- sists oxidation in the air at a red heat, and has very little affinity of combination with acids and salts. It occurs naturally, mixed with the me- tal above named, and also with iron, copper, lead, and silver, in ores which are called platinum ore, crude platinum, and platiniferous sand, chiefly in South America and the Ural Mountains. The obdurate na- ture of this metal renders its working very difficult. To separate platinum from the numerous other metals with which it is combined, the ore is car- ried through an elaborate series of pro- cesses, acted upon by acids, washed, dried, heated, rubbed to powder, pressed, triturated with water, elu- triated, made into a paste, pressed into a cylinder, removed as a sort of cake, raised to an intense heat, beaten into the form of an ingot, and this ingot converted into leaf, plate, or wire. Smelting, in the ordinary sense of the term, is of no use here ; platinum resists all furnace heat too effectually. MM. Deville and Debray have, however, recently discovered a mode of melting the metal by means of the oxyhydrogen blowpipe, and this has greatly extended the use of platinum, by rendering it cheaper. It was considered a great achieve- ment to prepare for the International Exhibition of 1862 an ingot of pla- tinum weighing 200 Ibs., valued at ^3,840. The great importance of platinum in the arts is due chiefly to its resistance of acids ; it is almost indispensable as a material for stills, vessels, and crucibles, in some of the chemical manufactures. Platinum weights, measures, and coins are sometimes made. Spongy Platinum, or Platinum Black, is the metal in a minutely-divided state. It is used in scientific chemistry, but not much in the arts. Plough. The more important ap- plication of this name is to the well- known farmingimplement. The car- penter's plough is a kind of plane which cuts a groove instead of a plane surface. Plumbag-o. (See BLACK LEAD.) Plumbing-, the work connected with the application of leaden sheets and pipes, depends chiefly on the processes of cutting and soldering. Roofs, flats, gutters, pipes, ridges, water-shoots, cisterns, tanks, small water-pipes, ball-cock apparatus all come within the domain of the plumber ; and for these purposes the chief material is lead, in the forms of sheet and pipe. (See LEAD MANU- FACTURE ; LEAD-PIPE MAKING ; SOLDER, SOLDERING.) Zinc is now partially superseding lead for some kinds of plumbing. Plush is a kind of unshorn vel- vet. (See VELVET.) Sometimes the yarns employed in weaving it are PNE 287 PON worsted and goat's hair, sometimes silk and cotton, sometimes silk only. There is always a double warp to it, one warp being brought up to the surface to produce the shaggy or plush effect. In the plush now used to so enormous an extent for covering men's hats, the cotton is hidden be- hind, and only the silk shown at the surface. Pneumatic Despatch. This, me- chanically considered, is a mode of shing a carriage through a tube having the air more rare in front the carriage than behind it. The principle was tried on a few systems of atmospheric railway between 1840 and 1845, but soon abandoned. A plan is in progress to work a pneumatic tube from Euston Station to the General Post Office ; but as this tube now (1868) stops short in Holborn, the operation is in abey- ance. The plan is to send mail- bags to and fro with great rapidity. The tube is about 4^ feet diameter, and laid underground. A steam- engine will pump out some of the air; and the difference of pressure before and behind the carriage will consti- tute the propulsive agency. The carriage is so shaped as to act as a piston in the tube ; and a very slight difference in the pressure before and behind it suffices to produce rapid movement. The cessation of the ope- rations of the Pneumatic Despatch Company was due partly to the diffi- culty of carrying the large pipes un- der the roadway of Holborn Hill and Holborn Bridge without disturbing the main-drainage works. It is pos- sible that, when the Holborn Valley Viaduct is finished, this difficulty may be surmounted. Point Net. (See BOBBIN NET ; LACE.) Polishing-. One among the many varieties of polishing is the lapping or glazing of cutlery and other steel goods. It is done on revolving wheels called laps, mostly made of wood with metal rims, touched with emery and oil. The metal is a soft al- loy, such as lead with about one-fifth its weight of tin. Some of the wheels, called glazers, are wholly oi' wood mahogany, walnut, oak, or birch touched on the rims with dry emery. The size of the wheel is made to de pend on the kind of article to be polished, especially razors ; and ac- cording as a coarse lap and heavy pressure, or a fine lap and light pres- sure, are applied, so does the steel assume a whitish or a blackish polish, each suitable for some parti- cular purposes. For razors and fine cutlery, leather wheels touched with dry crocus powder are used. Lap- ping on metal wheels, glazing on wheels of wood, and polishing on leather wheels, are sometimes re- quired in succession for the same article, or two out of the three. The polishing of stone, marble, wood, and other substances is treated under the proper headings. Polychrome Printing. (See COLOUR PRINTING.) Pontoon. This is usually a bridge constructed by military engineers for temporary purposes, such as the pas- sage of troops or guns over a river ; and every army of considerable size has a pontoon train among its departments. Closed wooden ves- sels ;> vessels of sheet-iron ; buoyant flat-bottomed boats, open at the top ; closed cylindrical vessels of copper ; india-rubber cylinders all are used to support a platform of beams or planks securely lashed with ropes. During a Volunteer review at Wind- sor, in June, 1868, a pontoon bridge was formed across the Thames in half an hour, strong enough to bear a continuous stream of armed men. The pontoons to support the plat- form were thin iron cylinders 22 feet long by 32 inches diameter. The late Captain Fowke invented a pon- toon that will collapse, for con- venience in carriage. It is made of strong canvas, stretched over a flat- elliptic wooden frame. It can be POP 288 FOR expanded by means of a screw-jack, which converts it into a kind of open boat, with the stretchers acting as gunwales. When extended, ihe pontoon is 22 feet long, 5 feet wide, 2 deep, having about 7 tons dis- placement. When packed for trans- port, it occupies a space only 16^ feet long, 5 feet wide, 2\ deep, or about 19 cubic feet, and weighs 260 Ibs. Volunteer engineers have made a bridge of such pontoons at the rate of 10 feet per minute. The inventor was wont to claim for this pontoon that it does not depend on air for its form ; that it need neither be made water-tight nor air-tight ; that it is lighter than an india-rubber pontoon of the same buoyancy ; that it forms an open boat when required ; that it is easily replaced ; that it is very portable. Poplar. The wood of this tree, especially the white poplar, is used in cabinet-making, toy-making, and turning ; that of the Canadian poplar is strong enough for carpentry pur- poses. Poplin was originally a French manufacture in silk ; but the Irish poplins of the present day are a mix- ture of silk warp with worsted weft ; in commoner kinds the silk is par- tially superseded by cotton or flax. Poppy. (See OPIUM.) Poppy oil is very useful for making paints, soaps, &c., and for culinary pur- poses. Porcelain, as a kind of translucent or semi-transparent ware, was not so early in vogue as the commoner kinds of opaque pottery ; the mate- rials required being more choice, and the baking processes needing more care. The Chinese were acquainted with the making of it, however, two thousand years ago ; and it is from them that we obtain the designation China or China-ware. In Europe, the experiments to discover the secret of its manufacture were first made in Saxony, by Bottger, early in the pre- sent centuiy ; and by using a peculiar white earth found at Schneeberg, he eventually succeeded. The Saxony Government, finding that Bottger could make white porcelain bearing some considerable resemblance to that of China, established a factory for him at Meissen, near Dresden, in 1810, where the manufacture was established under a very rigid system of secrecy ; Bavaria followed the example at Munich, and France at Paris. By mixing nitre, sea -salt, chalk, marl, alum, soda, gypsuTrTTand sand, the French produced what they called tendre porcel ain, fusible at a low temperature, coated with a soft glaze, and highly susceptible of ornament ; and their Sevres porcelain has ever since been held in high repute. In England successive advancements were made at Chelsea, Derby, Ply- mouth, and Worcester in the manu- facture of porcelain ; and the Wedg- woods, the Copelands, and the Min- tons gradually introduced it in Staf- fordshire, where it has now firmly taken root. A peculiar kind of stony earth, called Cornish stone, was, just about a century ago, found to be almost identical with the kaolin, or porcelain earth, employed by the Chinese ; and this was a great step towards the naturalisation of the manufacture in this country. Most of the processes in the porcelain manufacture are similar to those em- ployed for the production of earthen- ware and the better kinds of stone- ware. For these processes we may refer to POTTERY. The printing, noticed under EARTHENWARE, is, however, not often done on porcelain ; but, on the other hand, there are various refinements of processes, on which some remarks will be found under ENAMEL PAINTING ; PARIAN. Porphyry is an excessively hard stone, occasionally used for pilasters, plinths, slabs, mullers, pestle mor- tars, &c. ; but the labour of work- ing it prevents it from coming much into use. Sometimes, however, the specimens of workmanship produced FOR 289 POT are highly beautiful and valuable. There are granite-cutting works at Fowey Castle Mine, in Cornwall, at which porphyry- working is carried on. There are black, red, and green varieties of the stone, all equally sus- ceptible of polish. One table pro- duced at these works has a porphyry top, inlaid with specimens of fifty- tour kinds of Cornish stone. Porter. (See BREWING.) Port-fire is a sort of slow-match or fuse. Some kinds consist of a paper tube filled with slow-burning composition ; others of paper or sticks saturated with certain solu- tions. Artillerymen use them for firing off guns. Portland Cement. (See CE- MENT.) Portland Stone. (See STONE.) Potash, chemically considered, is an oxide of the metal potassium, although the name is popularly given to a more crude and complex sub- stance. The protoxide is the purest form of potash, or potassa, procured with great difficulty for use in delicate matters of chemistry and pharmacy. The hydrate is better known as caus- tic potash. The carbonate is the well-known potash of the shops. The nitrate is the equally well-known nitre or saltpetre. The chlorate is an important ingredient in tipping con- greve or lucifer matches. The other salts of potash are not much used in the arts. The more interesting of the processes connected with the manufacture of these substances are noticed under NITRE and POTASH MANUFACTURE ; while the practical applications of the substances them- selves come naturally for notice under GLASS MANUFACTURE, GUN- POWDER, MATCHES, SOAP MANU- FACTURE, &c. The metal potassium itself, like its companion metal so- dium, is not muchused in the metallic foims in the arts. The qualities of the two bear a very close resemblance. Potassium is obtained in the metallic form from tartrate of potash by a particular course of treatment with charcoal and naphtha. Potash Manufacture. The two principal forms of this useful sub- stance, the caustic and the carbonate, are made by different processes. (I.) Caustic Potash. Hydrate of lime, or lime-water, is added to a solution of carbonate of potash while the latter is boiling in an iron vessel. The carbonic acid gradually enters into combination with the lime, and leaves the potash free, though in a crude state ; but a little further purification brings it to the state of a solid, white, intensely alkaline substance. This form of potash is used as a caustic or cautery by surgeons. It forms also a soap with fat oil, leaving an alkaline liquid called soap lye or soap lees. (2.) Carbonate of 'Potash, composed chemically of one equi- valent of carbonic acid with one of potash, is produced in many differ- ent ways ; but burnt vegetables are the chief source, the potash being derived from the sap. Kelp and other kinds of seaweed are richer in soda; inland plants richer in potash. When inland plants are burned, the ashes are steeped with water in ves- sels having a double bottom ; after some time the liquid, impregnated with the alkali, is withdrawn, and the ashes are steeped time after time until all the potash has been extracted. The solution, called the lye, contains many other salts besides carbonate of potash ; it is evaporated to dryness, and then forms the crude potash sold to manu- facturers. Although all plants, and all parts of the same plant, yield pot- ash, there are inequalities in the amount; herbaceous plants yielding more than those of woody texture, the leaves more than the branches, and the bark more than the trunk. We could make our own potash in England, but it is cheaper to buy it from countries in which forests are more plentiful, in America and on the continent of Europe. Housewives U POT 290 POT among the peasantry in many coun- tries are accustomed to use the ashes of burnt plants for making a lye to serve as a substitute for soap in washing linen. Vetches stand high among potash-yielding plants. Beet-root sugar-making produces potash as an indirect result; there is alkali in the molasses or treacle left after the sugar is finished ; and this alkali, treated in a way which the French and German chemists have successfully applied, yields potash. The French also obtain this alkali from sheep's fleeces. The fleeces are washed to get off the grease or yelk; the solution is boiled ; the sediment is charred, steeped in water, evapo- rated, and potash is one of the re- sults. 9 Ibs of merino fleece contain about 7 ozs. of potash; and as 7,000,000 sheep are washed an- nually in France, it is computed that ^80,000 worth of potash might be obtained from this simple source. The French also obtain a little pot- ash from guano. In Germany there is a clayey deposit over a bed of rock-salt from which potash salts have been obtained ; and there are chemists who believe that the mineral world will by-and-by be the chief source of the alkali. Rock called felspar contains about one-seventh of its whole weight of potash; and the question is whether the alkali can be obtained from the stone by a profitable process. One plan that has been followed is to grind the rock to powder, mix it with pounded chalk and fluor-spar, heat the mixture to a kind of porous frit, boil the frit in water, and ob- tain potash from the lye into which the liquor is converted. The water of the ocean can be so treated as to give up its potash as well as its salts ; and potash is, in fact, thus ob- tained at La Camargue, in France. Crude potash varies greatly in the amount of impurities (sulphates, sili- cates, and chlorides of various kinds) contained; and each kind has its particular value in the market. It can be purified to any required degree by further processes. Pearlash is a tolerably pure potash. Our imports of potash and pearlash reach the large amount of 100,000 cwt. yearly. Potato Starch and Spirit. The potato, like a vast number of other plants, yields starch or farina when properly treated ; the manufacture is easy, and the quantity made exceed- ingly large. Our calico-printers use potato starch, in the form called British gum. Potato spirit, or potato brandy, is distilled in con- siderable quantities on the Conti- nent. Pot Metal is a grey, brittle alloy of copper and lead about 6 ozs. of lead to I Ib. of copper. Pottery. The facility of shaping apiece of soft clay into definite form is so great, that we need not wonder that the art of the potter is among the most ancient known to man. When a boy thiusts his thumb into a lump of clay to make a candlestick, he virtually becomes a potter ; and as clay is to be met with, in some form or other, in most countries, the pottery art must have arisen almost spontaneously. Some of the paint- ings and bas-reliefs on the tombs at Thebes show that the mode of mak- ing vessels in clay in use among the ancient Egyptians was very much like the simpler forms of the potter's art at the present day. After Europe began to emerge from the dark period of the middle ages, different countries gradually associated them- selves with the production of various kinds of pottery, many of which re^ main in repute to the present day. The Moors of Spain showed their skill in enamelled earthenware tiles; Delia Robbia, Giorgio di Gubbio, and Fontana produced beautiful specimens of pottery in Italy; Palissy did the same in France ; and English manufacturers at Bow and Chelsea ; while Josiah Wedgwood completely revolutionised the art. (On these mat- POT 291 POT ters see FAIENCE ; HENRI DEUX WARE; LUSTRE WARE; MAJOLICA WARE ; PALISSY WARE : WEDG- WOOD WARE.) At different times in the last century, potteries were esta- blished at Derby, Worcester, and Colebrook Dale, from which speci- mens of ware were sent out which still command the attention of col- lectors ; but Josiah Wedgwood was the great improver. At the present clay the trade chiefly centres in Staffordshire, where Hanley, Shel- ton, Longton, Lane End, Stoke, Burslem, Tunstall, and the inter- mediate towns and villages, con- stitute a district emphatically known as The Potteries. The inpredients for pottery comprise various kinds of clay, combined with other sub- stances according to the ware to be produced : the alumina of most kinds of clay, and the silica of most kinds of sand, being the rmalrTBases ; then potash is useful as another in- gredient for hard porcelain, soda for soft porcelain, baryta for stone ware ; while common, pottery, encaustic tiles, crucibles, earthenware, &c., re- sult from certain admixtures of lime and oxide of iron with the two bases. Generally speaking^-tfte "more the alumina, the hatder the ware ; the more the silica, the softer the ware : the latter is less dense, and bears less heat, than the former. Both in materials and in granular structure porcelain is about midway between pottery and glass. The following are the chief processes of manu- facture: (i.) Preparing the Slip. The name slip is given to the mix- ture of ingredients, whether for porcelain or for pottery, brought to a creamy liquid state. If flint is one of the ingredients, the flints are burned for many hours, broken into small fragments by stampers, ground into powder, and passed through sifters. Any other stony materials, such as felspar and broken earthen- ware, are in like manner ground and reduced in water to a creamy liquid. The clays blue, brown, yellow, white, as the case may be are blunged, that is, worked about with water until they form a smooth pulp ; if very stiff, they require to be cut and intermixed in a pug-mill before being blunged. The flinty cream and the clay are then mixed, and passed through sieves to render the mixture as fine and smooth as possible. This mixture, constituting slip, is boiled for many hours in a steam-heated vessel called a slip kiln ; the water evaporates, and the slip assumes a stiffer consistency. The mixture then requires ageing, the influence of time to work certain chemical changes in the mass, aided by me- chanical processes called wedging' and slapping. (2.) Throwing. Most articles of pottery and porcelain are thrown by means of the potter's wheel. This wheel is simply a flat circular board on the top of a verti- cal shaft or pillar ; the shaft is made to rotate, and a lump of prepared clay placed upon the board rotates with it. The thrower may rotate the board by a treadle, or an assist- ant by means of a winch-handle. Then, with moistened hands, he presses and squeezes and works the piece of revolving clay until he has brought it nearly to the shape of a teacup, basin, jug, or other vessel employing a few sim- ple tools of wood or horn to aid in giving the form. (3.) Turning. The articles made are circular, but are not yet smooth and regular ; they require turning. After being dried to a certain degree, each article is put upon a lathe and turned inside and out by means of suitable tools. Thus the substance is brought to an equable thickness, the inner and outer sur- faces are smoothed, and drnamental bands, headings, groovings, &c., pro- duced. (4.) Handling. Handles and spouts cannot be made on the potter's wheel ; they must be formed sepa- rately, and fixed afterwards. They are made by pressing pieces of clay POT 292 PRE in small moulds, and affixing them to the vessels by means of liquid slip, which forms a sufficient cement for the purpose. Ornamental flowers, sprigs, scrolls, &c., are often pro- duced in the same way. (5.) Flat Pressing, When the articles to be produced are rather flat than hollow, such as plates and saucers, and when they are not of a circular shape, such as square and oval dishes, they are made by pressing, not by throwing and turning. If the article is circu- lar, such as a dinner-plate, a plaster mould is placed upon a whirling- table, a flat slab of prepared clay is placed upon the mould, the table is made to rotate, and tools are brought down to bear upon the clay. It is thus that the mould produces the principal surface or front of the arti- cle, and the tools the back or secon- dary surfaces. By a peculiar ellipti- cal movement of the whirling-table, oval dishes or plates are produced, instead of circular. (6. ) Hollow Press- ing. The above kind is called flat ware ; deeper vessels constitute hol- low ware, of which a foot-pan may be taken as an example. The mould, in this case, is made in two or more pieces. The clay is worked into all the intricacies of the device, partly with the aid of tools, but chiefly by hand ; and, when finished, the vessel is extricated by taking the mould to pieces. For some forms of vessels the throwing and pressing processes are combined. (7.) Casting. Many arti- cles of pottery and porcelain are too intricate in form or too delicate in ornamentation to be produced either by throwing or pressing ; they re- quire to be cast. The prepared clay is brought to the state of a creamy liquid, which is poured into plaster of Paris moulds. It is in this way that the beautiful artistic articles no- ticed under PARIAN are produced, comprising statuettes, small busts, &c. (8.) Firing. All kinds of pottery and porcelain are mere cold, heavy, lumpish masses of clay, however ornate, until they have been baked or fired. The application of heat gives them a semi-vitrified character. The pottery-kiln is conveniently ar- ranged for holding a large number of articles at once, exposing them to a high heat, and at the same time shielding them from the direct action of flame and smoke. Large oval ves- sels, called seggars or saggers, are temporary receivers of the articles in the oven ; and such is the art dis- played in building them up, that a kiln will sometimes contain 30,000 articles of ware at once. The tempe- rature and duration of the firing vary with the kind of ware. (9.) Glazing. Usually the effect of firing is to con- vert the clay into the state called bis- cuit, having a texture something like that of a captain's or an Abernethy biscuit not glossy, but smooth, hard, and slightly vitreous. Some- times, by throwing salt into theoven, the ware is fired and glazed at the same time ; but more frequently the ware is fired into the state of biscuit, then glazed, and then fired again to vitrify the glaze. On this subject see GLAZE. The much-used blue and white printed ware is noticed under EARTHENWARE. In this im- portant manufacture it has been esti- mated that the Staffordshire Pot- teries consume 160,000 tons of clay, 450,000 tons of coal, 4,500 tons of ground bone, 67,000 Ibs. of cobalt, i,iootons of borax, and 12,000 ozs. of gold. But including all the coarse pottery, such as is made in Lam- beth, the total consumption of clay is supposed to exceed 1,000,000 tons. The produce being so large, we can afford to supply other countries with poltery, porcelain, and earthenware to a high value amounting in 1867 to /1, 600,000. Pounce, for sprinkling over wet writing, is made of powdered resin and cuttle-fish bones. Precious Metals. This desig- nation is rather a vague one, though I it is generally considered to apply PRE 293 PRE to gold and silver only, especially in the language of political econo- mists and bullionists. When the Commissioners of our two Interna- tional Exhibitions came to classify the multiplicity of trades and objects under their notice, they gave the name " Works in the Precious Me- tals " to the following: (i.) Com- munion plate ; such as altar dishes, chalices, patens, &c. (2.) Decora- tive gold and silver plate ; such as racing cups, testimonials, centre- pieces, salvers, candelabra, &c. (3.) Table plate ; such as soup and sauce tureens, dessert services, dinner and dessert spoons and ladles, ditto knives and forks, breakfast and tea services, claret jugs, wine coolers, cruet frames, c. (4.) Gold and silver plated goods. (5.) Sheffield and electro-plated goods. (6.) Gilt and ormolu work, for table and per- sonal decorations of various kinds. (7.) Jewellery containing precious stones. (8.) Gold and silver jewel- lery without precious stones. (9.) limitation jewellery of all kinds, such as is generally known as Birming- ham jewellery. There were a few other groups not so suitably placed; but the above certainly comprise a pretty wide range of what, without any great stretch of language, may be called works in the precious metals. Under appropriate headings most of these matters are touched upon in the present work. Precious Stones. (See DIA- MOND; GEMS AND PRECIOUS STONES ; JEWEL, JEWELLERY.) Preserved Meats. (See FOOD, PRESERVED.) Press. Various kinds of presses are described under COINING, HYDRAULIC PRESS, OIL MILL, PRINTING, &c. Pressed Glass. This cheap sub- stitute for cut glass is made at Bir- mingham, and still more largely at Newcastle-on-Tyne. The manufac- ture was introduced into England from America about the year 1852. There was at an earlier period some- thing like it under the name of pinched glass; but the present glass pressing consists in bringing flint glass into form by means of a metal mould and plunger. Pressed-glass tumblers, dishes, &c., are thus made, imitating in a rough way the bril- liancy of cut glass at a much lower price. In cut glass the ornamenta- tion costs much more than the ma- terial ; in pressed glass the material is more costly than the ornamenta- tion. What the workmen call fire- polish is the only polish produced in pressed glass ; and it is far in- ferior to the clear, even polish pro- duced by the grinding-wheel in cut glass. Moreover, the direct finish by the workman's hand is always preferable to the mechanical same- ness of pressed or moulded work. Nevertheless, pressed glass is as strong and nearly as brilliant as cut glass, and the demand for it is very large. Pressure Gauge. To show the force of steam contained in any cy- linder or other confined space, various forms of pressure gauge and vacuum gauge have been invented. In one form the indications are obtained from the compression of a known volume of air, contained in a conical cavity communicating at the top and bottom with a suitably-graduated glass tube. In another there is a diaphragm of mica, on which the pressure is exerted. In a third the pressure is exerted against a pair of saucer-shaped steel discs, united at their edges ; these move an index on a circular graduated dial. In a fourth the pressure is directed against flexi- ble metal plates, which act on a co- lumn of mercury ; and this column, rising or falling in a graduated tube, indicates the amount of pressure. Other pressure gauges for steim- engines have been invented in great variety. A deep-sea pressure gauge t for water instead of steam, is in- tended for measuring the depth of PRI 294 PRI the sea by the amount of the com- pression of water contained in a cy- lindrical glass vessel ; the vessel terminates above in a tinely-gra- duated glass tube, and is enclosed in a metallic case, and the pressure of any water contained in the vessel is measured by the amount of rising in the graduated tube. Prime Movers. Before a ma- chine can be set to work whether to forge an anchor or to head a pin, to blow a furnace or to stamp a shilling, to weave calico or to cut lucifer splints there must be taken into account the force which is to set everything in motion, the machine that is to move the machines. Hence engineers are called upon to pay great attention to what are called prime movers, and to study those which may be the best or the cheapest under given circumstances. Muscular power, water power, wind power, and steam power are the chief agencies whereby machinery is put in motion ; and the prime movers comprise, in effect, everything that belongs essentially to the develop- ment of these kinds of power. The Machinery Jury, at the last Inter- national Exhibition, treated under this heading all that concerned steam boilers and furnaces, super- heating steam apparatus, contriv- ances for preventing rust and foul- ing in boilers, water-softening for boilers, regenerative furnaces, fixed and portable steam-engines, rail and road locomotives, expansive work- ing apparatus, steam turbines, wind- mills, water-wheels, water turbines, water - pressure engines, vacuum- power engines, hot-air engines, compressed-air engines, gas engines, &c. Most of these matters are treated under their proper headings in this work. Prince's Metal is one of the numerous kinds of brass, containing more copper and less zinc than or- dinary brass. Printing-. This, one of the most valuable of all the practical arts, virtually began when any impression of any object was obtained upon an- other substance. But, in the sense usually understood, the Chinese seem to have invented the art. A piece of paper was cemented down upon a smooth block of wood ; a penman wrote a page-full of words or hieroglyphics on the paper ; an engraver cut the block in conformity with the writing ; the remaining paper was washed off; and then the block was ready to be printed from with any kind of ink. Any number of impressions could be taken from such a block ; but then as many blocks were needed as there were pages in the book. Whether de- rived from any Oriental source 01 an independent invention, such block-printing came into use in Europe about the year 1400 not for books, but for playing-cards and for single-page publications. Coster, a Dutch printer of such articles, introduced about 1420 the plan of cutting up an engraved block into numerous pieces, which could be interchanged, and thus made avail- able for printing many different kinds of books in succession whether the pieces were separate words or separate letters. Thus movable wood types could be substi- tuted for block prints. Somewhere about 1440, Gutenberg, at Mainz, in- vented (as is supposed) some mode of carving separate type-letters out of small pieces of metal ; but it was kept secret. At length, about 1450, Gutenberg, Faust, and Schceffer, in partnership, put in operation a plan of casting the types in melted metal. How much each contributed to the invention is not now known ; but the first result of their labour ap- pears to have been a printed edition of a Papal indulgence, struck off in 1453. Faust, when the partnership ended, was more successful than either of the other two, and was popularly believed to have had the PR I 295 PR1 advantage (or disadvantage) of Sa- tanic agency: hence the legend about the Devil and Dr. Faustus. Printing from cast metal types being thus established, the art spread, dur- ing the remainder of that century, to various parts of Europe. Among the most celebrated printers in Eng- land were William Caxton and Wynkyn de Worde. Caxton's first effort, the " Game of Chesse," was printed in 1474. The alphabetical let- ters at first employed were old Gothic, or what is now called black letter ; but this was almost entirely super- seded in later times by Roman type, and occasionally by Italic, orsloping. Every part of the printing art has of course undergone improvement dur- ing the last four hundred years ; but it is indisputable that the application of steam power to the working of the presses has been the most vital exten- sion of all one of the greatest aids to civilisation, indeed, that the world lias seen. In some kinds of printing (such as letter-press} the ink is at the surface of the printing block or plate, and not in the sunken parts ; in others (such as copper-plate] the ink is in the sunken parts, and not on the surface; while in a third kind (such as lithography] there is no apparent depression of the sur- face, but the ink is prevented from touching certain parts by chemical action. The chief practical details are described under the next two articles ; but subordinate matters are noticed under a multitude of other headings. Printing-, by Hand. The ordi- nary printing-press, worked by hand and not by steam, is simply one among many means of producing flat pressure, however the mecha- nism may be varied, (i.) Common Press. In this, probably the ear- liest form, invented by Blauw, the pressure is produced by turning a screw. The platen, which im- parts pressure to the paper, works up and down for each sheet or im- pression. The pressman, pulling a handle, works a screw which pro- duces these alternate movements. The form of type is conveyed under the platen by means of a carriage, and is run in and out by means of a winch and belt. On the outer end of the carriage is fixed the gallows, a skeleton frame for supporting two tympans, hinged together. These tympans are light square frames co- vered with parchment ; two or three layers of blanket are placed between them ; and, aided by a small iron frame called the frisket, they retain the sheet of paper in such a way as to enable it to be printed. The type is inked by means of balls or cushions of pelt or leather, dabbed over the form in such a way as to ink the surface of every type but not to sink into the interstices. There are thus several movements involved inking the form, adjust- ing the tympans and frisket, placing the paper, rolling in the carriage, working the screw-press, and all the reverse operations to prepare for the next impression. (2.) Stanhope Press. Among a multitude of im- provements on Blauw's old screw- press is that which was invented by Earl Stanhope. This is also a screw- press ; but the screw action is so well managed as to economise force where it is least wanted, and to bring it on with great power just at the moment when the actual pressure of the paper upon the form is needed. The raising of the platen, after each impression, is aided by the de- scent of a balance-weight. The bed on which the form of type rests is of such dimensions as to print a much larger sheet than is usually printed by the common press. The Stan- hope press is worked by two men one to ink the type and arrange the form and paper ; the other to manage the lever which works the screw and platen. Many minor adjustments are attended to, to in- sure that the sheet of paper shall PRI 290 PRI lie square on the form, and that it shall not be soiled with ink on the margin. As each sheet can be printed on one side only at a time, the form of type has to be changed before the other side can be printed. If woodcuts are incorporated in the page of type, greater care and deli- cacy are required in some of the ma- nipulations. (3.) Albion Press. In this form of press the old wooden basis of the Stanhope press is superseded by iron ; a combination of cam and lever is used instead of a screw ; a spiral spring is used instead of a balance-weight; and various other improvements have rendered the press both easier to work and more rapid in its action. (4.) Columbian Press. This is another modern im- provement on the Stanhope ; and it has, like the Albion, been made the basis of still further improvements by later inventors. The chief feature is a combination of powerful levers to produce maximum pressure just at the proper moment. All these machines require some kind of inking apparatus. In the earlier modes of printing, the inkingballs or cushions, just noticed, were always used ; but an inking roller is now coming more and more into use. Being made of glue and treacle, it has a remarkable degree of elasticity, which qualifies it to press iipon the types veiy inti- mately. It is provided with handles in such a way as to be easily rolled along any flat surface. The ink is spread out upon a flat table with a muller; and the roller, by being passed over this table, takes up a thin layer of ink over its whole sur- face ; this ink is then transferred to the type by rolling. Sometimes a distributing roller is also used, which takes up a layer of ink from the table, and distributes it to the other roller. The quality of the ink employed varies with the kind of work to be done. Printing-, by Steam. The appli- cation of steam power to the print- ing-press has been one of the most important of all stimuli to the gene- ral spread of popular education, by enabling publishers to produce at a cheap rate books, periodicals, and newspapers which would else be quite beyond the reach of the labour- ing classes. We may feel pretty cer- tain that neither the penny post nor the electric telegraph would have been established without it ; the incen- tive for such daring novelties would have been wanting, (i.) Konig 3 s Machine. The first actual printing machine worked by steam power was invented by a German named Konig, early in the present century. After many abortive attempts in Germany and in England, Konig at length had the pleasure of seeing a steam-printing machine of his set up in the Times printing-office; and the number of that journal for November 29, 1814, inaugurated the new era. The type was laid on a flat surface, the sheet of paper was wound round a cylinder, and the printing was effected by rolling the cylinder over the type. The amount of automatic action in a machine so recently invented was highly credit- able to the ability of Konig. As the Times said in a leading article on that day: "The machine itself places the form, inks it, adjusts the paper to the form newly inked, stamps the sheet, and gives it forth to the hands of the attendant, at the same time withdrawing the form for a fresh coat of ink, which itself again distributes, to meet the ensuing sheet now advancing for impres- sion ; and the whole of these com- plicated acts is performed with such a velocity and simultaneousness of movement, that no less than 1,100 sheets are impressed in one hour." Ten years later, on December 3rd, 1824, the Times began to be printed on both sides at once by an im- provement of Konig's machine ; this enabled them to produce 2,000 copies per hour. (2.) Cowper and PRI 297 PRI Apple gaMs Machine. In 1818 a patent was taken out in the joint names of these two inventors ; and from that year an almost uninter- rupted series of improvements was introduced by them. The principal parts of the machine patented were, we believe, Professor Cowper's. There were drums introduced be- tween the printing cylinders ; the sheet of paper was conveyed over one of these drums and under an- other; the types for the two sides of the sheet were arranged at cal- culated distances ; and the sheet was caused by the rotation of the drums to travel to the second cylinder after being printed on one side by the first. There was thus insured ac- curacy of register in the printing of the two sides of the sheet. (3.) Two- Cylinder Machine. Instead of trac- ing in detail the almost numberless improvements introduced by these two inventors, let us briefly describe the two - cylinder machine, with which a vast amount of book and newspaper printing is executed. The sheet of paper to be printed is laid by a boy, the layer-on, on a feeding-apron which winds round two rollers at the end ; it is carried on under the web roller and the smoothing roller to the entering drum, over which it passes ; then it is seized between two systems of endless tapes, so arranged that each tape shall only touch a white margin of the paper, and not a part that is to be printed. The tapes retain the sheet in position while it is being carried over and under the drums and printing cylinders ; and they never let go of it till it has been printed on both sides. The print- ing cylinders are covered with cloth or blanket, to make the surface slightly soft and yielding. The two forms of type, one for each side, are ranged horizontally, side by side, on a carriage which alternately carries them under the cylinders and back again. There is a complete set of inking apparatus to each form, most ingeniously inking the types just at the moment when they are not under the cylinders. The apparatus is rather complicated, comprising ductor roller, ink trough, vibrating roller, inking table, distributing rollers, &c. The whole operations may be said to group themselves into three sets the inking of the forms of type ; the shifting of these forms to and fro on the bed of the ma- chine; and the pressing of the sheet of paper on the two forms in succes- sion by the agency of the cylinders, drums, and tapes. Two -cylinder machines now print average book- work at a rate of about 700 copies per hour. (4.) Four-Cylinder Ma- chine. In 1827, Messrs. Cowperand Applegath, by inventing a four- cylinder machine, enabled the pro- prietors of the Times to print 6,000 copies per hour. There are four feeding-aprons, four drums, four sets of tapes, four printing cylinders, Sec. The sheets of paper are carried up and down, over and under, with wonderful quickness and accuracy. There is not really any new prin- ciple at work in this machine, distinct from the two-cylinder, but there are a number of additional minor ad- justments of a very ingenious kind. These machines, however, for news- papers do not register so accurately as the two-cylinder used in book- work. (5.) Vertical Cylinder Ma- chine. Another period of about twenty years elapsed, during which the four-cylinder machine was used at the Times office. But there came a period when the publishers wished to issue 10,000 copies per hour, which Mr. Applegath found him- self unable to accomplish with any- practicable arrangement of hori- zontal cylinders. He therefore in- vented a very beautiful arrangement of "vertical cylinders, eight of them to press the sheets of paper against a larger central cylinder on which the forms of type were placed, A PRI 298 PRI reciprocating motion was merely superseded by a more rapid circular one. The machines, in their con- struction, have a central cylinder 64 inches in diameter, with the forms of type on its surface. The eight surrounding cylinders, 13 inches in diameter, are covered with cloth ; and all nine rotate on vertical axes. The inking rollers are also vertical, and supply the type with ink at re- gular intervals during the rotation of the type cylinder. There being eight pressing cylinders and eight sets of inking rollers, eight sheets of paper can be printed during one revolu- tion of the type-cylinder. There are eight layers-on, who supply sheets of paper to eight tables or stands, on which they are caught by a series of tapes, and carried vertically so as to be acted on by the pressure rollers. Each layer-on places 24 sheets per minute, and the printing is thus at the rate of 8 x 24 = 192 per minute, or 11,520 per hour. Allowing for delays and adjust- ments, this gives practically 10,000 per hour. It was deservedly re- corded as a great achievement, that on May 7th, 1850, an edition of 34,000 copies of the Times was printed in four hours, the matter of four-fifths of which was not even written at seven o'clock on the pre- vious evening ! By various improve- ments the rate of working was increased. On the day when the Duke of Wellington's funeral was described (Nov. 14, 1852), 70,000 copies of the Times were printed, some on one machine at 11,000 per hour, others on a second machine at 12,000. Still further improvements afterwards raised the speed to 14,000 and even 16,000. (6.) Hoe's Machine. This, which is an American inven- tion, has many advantages in regard to compactness, and is now much employed in newspaper-printing in England. It can be made to print one, two, or up to ten sheets at once; and there are certain facili- ties for placing and removing the sheets of paper in which it excels Applegath's. In the simplest ar- rangement, the form of type is ad- justed to one-fourth of the surface of a revolving horizontal cylinder, the other three-fourths being used for distributing the ink. The im- pression-cylinders are of course parallel with the type-cylinder, and act with it. The inking arrange- ments are entirely under the cylin- ders, arid are remarkable for their ingenuity and completeness. In the great ten-cylinder machine (which will print 18,000 to 20,000 copies per hour), the form of type is car- ried round to each of the ten im- pression cylinders in succession, and prints the sheet of paper which each bears. Most of the penny daily papers are now printed on these beautiful and powerful ten-cylinder Hoe machines. (7.) Flat-printing Machines. Although steam power is mostly applied to the various kinds of cylinder machines, it is also suc- cessfully adopted for flat or platen presses, in which the pressure is produced by the downward motion of a platen. There is no reason why the work should not be equally good with that of the hand-worked press, while the speed of working can be greatly increased. But as no flat press prints more than one side at a time, whereas a cylinder machine prints both sides, the latter will have the advantage in speed of working. To print both sides at once is the next great invention to be looked forward to; and to do this printing on an endless web of paper, which the machine cuts into sheets as it proceeds. Already such progress has been made as to give hope that this grand result will one day be realised. [To show what wonderful results are now produced by the combined influence of electro-telegraphic re- porting and the use of Hoe's ma- chine, the following achievement is PRO 299 PUD worthy of record : Mr. Gladstone made a speech at Liverpool, five columns in length, on a particular evening in December, 1868. It was reported in short-hand, then written out in full, and then tele- graphed, word by word, to Edin- burgh ; this telegraphing occupied from 1 1 P.M. to 4 A.M. ; and yet by 6.30 A.M. 30,000 copies of the Scotsman newspaper, containing the speech in full, were printed, folded, and despatched.] Proof House. The proving of gun-barrels is an important process in the manufacture of fire-arms ; and \\\e proof -houses, in Birmingham and elsewhere, are specially fitted up for this duty. All English gun-barrels must, by Act of Parliament, be proved either in that town or in the metro- polis. All barrels are to be proved twice first provisionally, and then definitely when the gun is ready to be put together. Breech -loading barrels are proved the second time when the breech-loading apparatus is attached and complete. The size of the bore at the time of proof is stamped on every barrel in plain figures. More than 600,000 musket and rifle barrels are annually proved in England alone. There are at pre- sent four proof-houses in England the trade and the Government proof- houses in Birmingham, the trade proof-house in London, and the Government proof-house at Enfield. The first of these proves as many bar- rels as all the other three combined. The average failure is about 4 per cent. ; that is, four barrels in 100 fail to withstand the test of proof to the required degree. The proof itself consists in firing with heavier bullets and larger charges than are to be used with the finished gun ; if the barrel bears this test favourably, it is deemed fitted for its work. The proof of large ordnance, accurately and highly finished as they are at the present day, is much more severe. Protean Stone, or Artificial Ivory, are names given to a peculiar preparation of gypsum, applied to ornamental manufactures. Mr. Che- verton, studying the action of water on lime, was led to this new inven- tion. His plan comprises the mak- ing of a kind of alabaster, capable of being wrought into ornamental forms, and into a fine powder suit- able for compressing into a mould. Peculiar processes of watering, heat- ing, cooling, and drying are em- ployed to bring about the desired result ; and when the manufactured article is to present a translucent or semi-transparent appearance, it is immersed in some kind of oil or var- nish. It is variously coloured, by dissolving the requisite colours in water, and either immersing the finished article in it as in a liquid dye, or sprinkling the solution in such a way as to produce a mottled appear- ance. The substance has been used for making door-handles, finger- plates, inkstands, letter-weights, &c. Prussian Blue is a compound of cyanogen and iron, pre, ared by a complicated chemical process from horns, hoofs, woollen rags, and many other substances. This beau- tiful pigment, called in France bleu de Paris, is largely used by colour- makers, painters, dyers, calico- printers, and blue-ink makers. Puddling: Furnace. The fur- nace employed in puddling iron (see IRON REFINING AND PUD- DLING), or converting it from the raw to the wrought state, has a hearth either of fire-brick or of cast-iron plate covered with a layer of slag. This hearth, which constitutes a kind of oven, is heated in a peculiar way. At one end of it is a fire-place, with a brick bridge or elevation stand- ing up some inches high between the two ; the flame and hot air, passing over this bridge, dash against a covered roof of the hearth, and are thence reflected downwards with great force upon the molten contents. A chimney 40 or 50 feet high pro- PUG 300 pmi duces a draught which maintains a strong heat in the fire-place, and also draws the flame with considerable vigour into the hearth or oven. Ahole on one side of the furnace, closed when necessary by an iron and brick door, enables the puddler to insert a long iron bar during the course of the operations. Pug- Mill. (See BRICK MAKING; PORCP:LAIN; POTTERY; TILES.) Pulley. The making of the blocks around which the ropes of a pulley- work is noticed under BLOCK MA- CHINERY. Pulping- Machine. Graziers and farmers now pay great attention to the preparation of food for their cat- tle. Not only does the turnip cutter bring the vegetable to a state more suitable for the animal to eat it, but the pulping machine carries the pro- cess still further, by reducing the turnips and man gold- wurzel to a condition of complete pulp. By this means the pulp can be mixed more readily with the chaff of hay and straw, better insuring the combina- tion of all into one article of diet. Knives disposed in various ways, orspikesattached to revolving shafts, form the chief features in various kinds of pulping machine. Pumice; Pumice Stone. Pumice is a kind of grey lava, ob- tained mostly from a part of Italy where volcanoes have at one time been active. Being very hard and brittle, it is much used in polishing stone, slate, glass, metal, wood, and varnished and painted goods ; being used sometimes in the lump and sometimes in powder. Some of the varieties are so porous as to be less than half their weight of water. Pump. However pumps may vary in their mode of action, they all raise water from one level to another. (i.) The suction pump has a barrel, piston, pipes, and valves. When it is worked by a handle at the top, the piston draws air from the barrel, and water rushes in from below to fill up the vacuum. By means of suitable valves, this water is drawn up to the surface. Owing to the limits of atmospheric pres- sure, 33 feet is the greatest depth from which water can be pumped up by this means. (2.) The force pump. Here, while the upward movement of the piston draws water into the barrel by suction, the down- ward motion presses on that water, and forces it into a lateral ascend- ing pipe with great power. (3.) The chain pump has an endless chain of boards or flaps, which just fit the section of a square tube or trunk ; when the chain is worked so that the boards move upwards through the trunk, each board car- ries its quota of water up to the top. There are several other varieties ot pump, the most powerful of which is noticed under TURBINE ; while a recent novelty is treated under TUBE WELL. Pumping: Engines. The deep mines of coal and other minerals are often so flooded with water that vast arrangements are needed for pumping them. When the mine- is shallow and the water small in amount, a gin or whimsey may suf- fice. This consists of two buckets raised and lowered by horse power, an empty bucket descending while a full one ascends. For deeper mines, water power is applied in countries and districts where coal is dear, but steam power in the United Kingdom. In the water-power sys- tem, water flows over many wheels in succession, and is thus made to do duty two or more times over. In the steam-power system, a steam- engine is built near the mouth of the mine, and connected with pumps, &c., down the shaft. The pumps employed are lift pumps, elevating the water from the mine rather by lifting it than by suction. The lifts, or columns of water lifted, are many yards in height, and there is a cis- tern at the boUom of each ; the lilt PUN 301 PYR draws up the water from one cistern to another. There is in reality only one piston-rod from the top to the bot- tom of the shaft, but as many pumps as there are lifts ; and the pump-rod of each pump has a reciprocating or up-and-down motion. In Corn- wall, where coal is dearer than in the colliery districts, the steam- engines employed at the tin and copper mines are specially con- structed to do as much work as pos- sible for each ton of coals; this ratio is called the duty, which is becoming higher and higher in pro- portion as improvements in fur- naces, boilers, and working gear are introduced. A century ago, an at- mospheric engine, before the inven- tion of Watt, performed a duty estimated by raising 5, 500,000 Ibs. of water i foot high by the expen- diture of i bushel of Welsh coal ; half a century ago the quantity was 28,000,000, and now it is nearly 70,000,000; in some special instances more than 100,000,000. One end of the engine-beam hangs directly over the shaft, and the other end has a balance- weight to render easier the raising of the pump-rod. Some of the cylinders of these engines are as much as 100 inches diameter, and in those the steam is worked expansively. Punch. ; Punching 1 Machine. The punches used in various me- chanical trades have mostly a kind of hollow tube at the lower end of a shank. The extremity of the tube being made sharp, a smart blow will cause the punch to cut out a small circular piece of wood, metal, or leather. A duplex punch, such as is used by railway-ticket col- lectors, acts like pincers, and requires no blow in the act of punching. For the punching machines worked by steam, see MACHINE TOOLS. Purple. Purple colours and dyes are mostly produced by mixing reds with blues. There is one, however, orchil, which is a sort of natural i purple, and there is another belong- ing to the coal-tar series. (See ANILINE COLOURS.) The purple of Cassius (chloride of gold and tin) produces the beautiful ruby colour for glass-staining. Putty. The oil putty employed by painters and glaziers is made of whiting and drying linseed oil. It is sometimes rendered a little elastic by the addition of a portion of tal- low. In glue putty, employed in some trades, the oil is replaced by hot melted glue. Putty Powder is the absurd name for a hard white powdered oxide of tin, much used in polishing stone and metal, and in giving a white colour to enamels. Pyrites are mostly sulphurets of the metals. Iron Pyrites, which is a sulphuret of iron, is a brassy-look- ing mineral, much employed in the manufacture of alum and sulphuric acid. Copper Pyrites is a sulphuret of copper and iron, softer and more yielding than iron pyrites; this is the ore from which most of our metallic copper is obtained by smelting. (See COPPER.) There are also Cobalt and Nickel pyrites, not much used in the arts. No less than 1 14,000 tons of pyrites were imported in 1867. Pyrolig-neous Acid is a name which means hot -wood acid. Branches and small billets of many kinds of wood, such as fir, ash, oak, beech, and birch, when burned in close iron retorts, give off this acid, which distils over into separate vessels. In some of the manufacto- ries where this acid is made, saw- dust, chips, shavings, and spent dye- woods are rendered available, using up waste materials in an economical way. The acid is used in making acetates for dyers and calico-printers, and vinegar for pickling. Pyrometer, or fire -measurer, is a kind of thermometer which measures very high degrees of heat. The form adopted by Wedgwood acts by the continuous contraction of a small PVR 302 PYX ball of porcelain clay when under the influence of a continuously-increas- ing heat. It used to be supposed that the contraction was really uni- form ; but it is now known to fluctu- ate both with the height and with the duration of heating. DanielPs pyrometer depends on the expansion of a bar of platinum enclosed in a cylinder of fire-clay or plumbago ; the expansion is tolerably uniform, but minute in quantity and difficult of observation. A more recent in- vention by Bystrom measures the amount of heat absorbed by a ball of platinum by the elevation of tempe- rature of a known bulk of water in which it has been plunged. The apparatus is rather complicated ; comprising a horizontal porcelain tube, another tube placed obliquely, a ball of platinum, a small iron rod, a small square brass cistern filled with water, a wooden box surrounding the cistern, and a small wire-gauze cage. This instrument is considered to be more accurate than either Wedgwood's or Daniell's. Pyro- meters of some form or other are useful in the porcelain, enamel, glass, steel, and other manufac- tures. Pyrotechny. The firework- makers employ a large variety of substances to produce their dazzling displays : gunpowder, sulphur, char- coal, saltpetre, steel and iron filings, zinc and copper filings, antimony, ni- trates and acetates of several metals, &c. Explosive noises, brilliant flashes, streams of sparks, coloured fumes, and starry spangles accom- pany th e exhibition of rotating wheels and swiftly-moving projectiles. A tube made of paper or pasteboard is a frequently-employed receptacle for the various mixtures ; and the squib, cracker, Roman candle, rocket, Cathe- rine wheel, serpent, Bengal light, Chinese fire, star, shower, golden rain, silver rain, blazing comet, &c., are the forms in which the made- up pieces display themselves. ^-The pyrotechny at the Crystal Palace is now the finest to be witnessed in this country. Pyroxylic Spirit, obtained from pyroligneous acid, is a cheap substi- tute for alcohol or spirit of wine in making varnishes, and in other pro- cesses in the arts. An unpleasant odour prevents it from being used as a beverage. Pyx. The Trial of the Pyx (see COINING ; MINT) is a kind of official weighing and assaying of the coin- age, to ascertain that the authorities at the Mint have made the coins of right weight and quality. The persons employed in it are Privy Councillors, Treasury andExchequei officials, Mint officials, and mem- bers of the Goldsmiths' Company. The localities for the inquiry are at Westminster and at Goldsmiths' Hall. The trial takes place at inter- vals of a few years. Specimens of coinage of various dates are put into a strong box, called the pyx, dupli- cate keys of which are guarded with great care. It is correctly assumed that, at each trial, the specimens in the pyx are fair average samples of all that have been coined since the last trial. Most minute processes of weighing and assaying are carried on ; the assayers even talk about such an incredibly minute quantity as one millionth ofagrain in the weight of a sovereign. As absolute accu- racy is, of course, unattainable, there is a margin or percentage of error allowed, called the remedy; and if the Master of the Mint is found not to have exceeded this amount, the trial of the pyx ends with a verdict in his favour, which is forthwith officially announced. QUA 303 QUA Q. Quarry; Quarrying.. Quarry is the usual name for the places in which stone is excavated for build- ing and other purposes. Sometimes a hill is wholly or partially quarried away ; sometimes a wide opening is dug in the level ground, to reach valuable stone underneath. What- ever may be the kind of stone, the processes of quarrying bear a general resemblance in all. The digging does not greatly differ from that in Devon and Cornwall for mineral ores. The borer or jumper, the hammer, the scraper, the claying bar, the needle, the tamping bar these are the chief mechanical tools. In rude countries, and in our own country long ago, the stone was loosened, dislodged, and raised wholly by mechanical means. But practically, blasting is now very generally adopted in England as a powerful auxiliary to the quarryman. Under BLASTING the application of gunpowder to mining is described. In quarrying the details are varied by two circumstances the hardness of some of the stone, and the desir- ability of obtaining pieces of large size and regular shape. For granite the boring of the blast-holes is very tedious work, wearing out rapidly the steel of the jumper, and consuming much time and strength on the part of the workmen. Three men, work- ing at one hole (one to hold and ad- just the jumper and two to strike it with hammers) can only make about 4 feet depth of hole, 3 inches diame- ter, in hard granite, in a day's work ; the tool requiring to be sharpened every half-hour or so. It is alto- gether laborious work, for the ham- mer used in striking a 3-inch jumper weighs iSlbs. There is another kind, called the churn jumper, which is used without a hammer, and is worked by a peculiar kind of twisting or grinding action, rapidly destructive of the steel bit at the end. The drill- ing process, effected by machinery, and employed in some kinds of tunnelling, is noticed under ROCK BORING. The number, depth, width, and direction of the bore-holes are made dependent on the natural strati- fication of the stone, its hardness, and the size of the blocks required ; and the quantity of powder for the blast is determined by similar con- siderations. The introduction of the blasting-powder into the holes, and the tamping with clay, wood plugs, &c., to ram it well in, require more care in quarrying than in mining. If the stone is of a kind which pos- sesses cleavage planes, it is separated into parallel masses by means of iron wedges driven in with heavy hammers, without the tearing and disruption which result from blasting. Sometimes blasting is adopted, in the first instance, to loosen a large mass, and then this is further separated by means of wedges driven in at the cleavage planes. Nearly all the blocks of stone undergo some dress- ing or other after being separated from the parent rock ; it can be done as cheaply at the quarry as else- where, and lessens the cost of freight. Sometimes, at the Dartmoor granite quarries, a mass of 5,000 cubic feet is brought down at one time ; and this, whether in a few pieces or in many, requires much subsequent working before it will be fit for use in paving or building. Along the lines selected for the severance, iron wedges are driven into holes bored in a row ; and the stone splits by the simultaneous percussion of many such wedges. Some of the irregularities are then removed by spalling, or striking with an axe-formed hammer, or by means of a kevel ; next comes scabbing, which brings the stone to a QUA 304 QUI general level, though veiy rough, by the blows of heavy pointed picks (this relates to hard stone, such as granite). The grinding and polish- ing are not done at the quarry, al- though the quarry owners may have an establishment for that purpose near at hand. Softer kinds, such as freestone and sandstone, are much more easily dressed at the quarry, For various subsidiary details see BLASTING ; GRANITE ; SAFETY FUSE; SLATE, SLATE QUARRY- ING ; SLATING; STONE; STONE WORKING, &c. Quartz, if pure, is silica or rock crystal, or oxide of silica, in the same way that pure alumina is oxide of aluminium ; but it is nearly always found mixed with other substances. It is a component element in granite and many other kinds of stone ; it is the chief ingredient in sea-sand ; and many kinds of precious stone (car- nelian, chalcedony, jasper, agate, amethyst, cairngorm, rock crystal, &c.) are almost wholly quartz. Quartz veins are the great store- house whence gold is obtained. Queen's Metal is one of the white alloys, made of tin, with a little cop- per, antimony, and bismuth. Quercitron, prepared from the bark of the yellow oak, produces a fine yellow colour much used in dye- ing and calico-printing. Quick Lime. (See LIME.) Quick Match, for igniting blast- ing charges, &c., is a kind of wick or cotton rope dipped in vinegar and saltpetre. The time taken to burn a given length is accurately noted. Quicksilver Mining. Quick- silver or mercury is obtained from Idria, Spain, and Peru. There are less abundant sources of the metal in Bavaria, Hungary, Sweden, Mexico, Chili, China, and Japan, The chief ore whence it is obtained is the sulphuret or sulphide, nearly the same thing as cinnabar, a reddish mineral; it is found interstratified with sandstone and shale. Some of the mercury is, however, found pure or native in isolated drops in the sul- phuret, or sometimes in little pools in cavities. The value of the metal, and the unhealthiness of the vapour which rises from it, determine the mode in which the extraction is managed. At Idria, in Austria, a kind of bituminous sulphuret, en- closing globules of mercury, is found at 'a depth of 800 or 900 feet, in the form of veins or lodes in limestone and schist rock ; and the workings are conducted by means of small galleries. The ore, when obtained by digging, &c., is carefully ex- amined, and separated by hand into various parcels, according to the size and richness of the pieces. It is dis- tilled at a high temperature in a large and peculiarly-constructed furnace ; the sulphur escapes in the form of sul- phurous acid gas ; while the mercury, after rising in vapour, passes off into chambers where it condenses and fails in liquid drops. Collected from gutters into which it flows, the mer- cury is filtered through thick linen bags, and poured into iron bottles for market. 100 parts of the ore yield about 8 of metal. Beech wood is employed as fuel. At Al- maden, in Spain, there is a vein of the sulphuret from 40 to 50 feet thick, at a depth of about 900 feet below the surface ; the mode of ex- traction (with brushwood as fuel) is more rude than in Istria, and more injurious to the workmen by the es- cape of mercurial vapour. In Rhe- nish Bavaria, where the ore is a mix- ture of cinnabar with calcareous rock, the roasting is so conducted that the sulphur leaves the mercury to com- bine with the lime, and the metal condenses from the state of vapour into its usual fluid condition. So great is the quantity of quicksilver used in the arts, tha't 2,200,000 Ibs. of it were imported into the United Kingdom in 1867. Quill Pe-is. Notwithstanding the vast use of steel pens, the quill RAB 305 RAI still remains infavour ; fornometallic pen whatever has yet been invented equal to the quill in certain qualities. The goose, swan, crow, ostrich, and turkey yield quills suitable for making into pens ; but the first- named are by far the largest in de- mand. Some of the Russian geese are reared principally for the sake of the quills, yielding about twenty each in a year on an average. The size of the* barrel is the chief test of excellence. In quill-dressing, the quills are sorted irti.opritr.es, seconds, and pinions. They are plunged into hot sand, which loosens the outer skin, and enables it to be scraped off; the inner membrane is also shrivelled up by the heat, and the oily matter dissipated. The pro- cesses are repeated two or three times until the barrel of the quill be- comes horny and transparent. They are sometimes hardened and made yellow by means of nitric acid or alum-water. Some quill-dressers use hot water instead of hot sand. Crow quills are used for making small fine pens, useful in some kinds of drawing. Quill nibs are made by cutting a quill-barrel into six or eight pieces, shaped like the familiar steel pens, by the aid of a few simple tools. In making quill pens for sale, the penknife is found to be more expeditious than any machine ever yet invented ; a skilful hand will make 800 in a day. R. Babbit Skins are not only very largely used in hat-making, and their pelts in making glue and size, but the furriers have devised means for so dressing these skins as to imitate ermine, miniver, and many other kinds of costly fur. Back Work, in machinery, is a cog-wheel working into a cogged bar. If the wheel rotates, it will make the bar advance longitudinally; if the bar advances, it will cause the wheel to rotate. Bags. All kinds of worn-out woven goods are available in some or other of the manufacturing arts. AVoollen rags are converted into Flock and Shoddy (which see); linen and cotton rags, especially the former, supply the paper-mills ; while refuse, useful for nothing else, is acceptable to the farmer as ma- nure. In addition to our home sup- ply, we have in recent years imported 40,000 tons of foreign rags annu- ally. Bails. Important improvements are being gradually made in the rails for railways, chiefly by the substi- tution of steel for iron. At the Camden depot a few years ago, two Bessemer steel rails were tested against two iron rails, alike in size and shape, and subjected to just the same amount and weight of traffic. After three years' incessant wear, during which the iron rails had been removed and renewed no less than seven times, the steel rails were found to be so little worn as to be capable of rendering much longer service. The iron rails had been worn on both surfaces in succession, while those of steel had only been worn on one. It was calculated that the steel rail was twenty times as durable as the iron ; and as the difference in the cost of the two metals is not nearly so great as this, steel rails will be cheaper in the end. It was found that 10,000,000 wheels had passed over the steel rails before the weight was reduced by wearing 7| Ibs. per yard ; in other words, 370 wheels, at the average rate of speed, only rub off one grain weight from a yard of steel rail. Bailways. A railway is, in an eminent degree, the result of civil engineering, a subject beyond the scope of this work. As mere me- RAI 305 RAZ chanical labour the working and placing of earth, stone, brick, iron, and timber the making of a railway is like that of any other constructive work, differing rather in degree than in kind ; but the planning to attain the desired results, and the overcom- ing of difficulties to this attainment, require that sort of brain-work for which civil engineers are so eminent. Bridges, embankments, viaducts, galleries, cuttings, tunnels, inclines, sea-walls ; the making of foundations far beneath the beds of rivers ; the solidifying of quaking bogs and morasses ; the piercing of mountains to the extent of eight miles in dark- ness (as in the Mont Cenis tunnel railway) ; the carrying of the iron road and the locomotive over the mountains themselves (as in the Mont Cenis summit railway) ; the connection of islands with the main- land (as at the Menai) ; the burrow- ing under the roads of a town (as in the Underground Railway) ; the crossing of bays which are twice a day dry land and twice a day under water ; the carrying of a double traffic across a river, by a railway over a carriage-way; the carrying of railways over ravines at a height of 200 or 300 feet these, and such as these, are the works which render railway engineering so vast and interesting a subject. A few collateral matters are noticed un- der LOCOMOTIVE, RAILWAY; RAILS; ROLLING STOCK; TURN- TABLE. Raisins. (See FRUIT, DRIED.) Rape Seed; Rape Oil. The plant which yields these products is another species of the same genus as that which yields colza oil. Rape oil, produced in the way described under OIL MILL, is largely used for lamps, but still more extensively for lubricating machinery. It has been stated that 1,000 acres of land, sown with rape, would be necessary to supply one year's consumption of oil for lubricating the locomotives of the London and North Western Railway. Rasps. (See FILE MAKING.) Ratafia. (See LIQUEURS.) Ratchet, in machinery or wheel- work, is a very short lever, pivoted at one end, and so placed at the other as to catch into the teeth of a ratchet-wheel. The arrangement is such that the wheel can revolve in one direction only, so long as the ratchet is free to act. Rattans are canes obtained from many species of Oriental palm. Vary- ing greatly as they do in length and thickness, they are used for a great variety of wicker-work in the East, also for making ropes, cables, and even bridges. The Malacca canes used for walking-sticks and umbrellas are a species of rattan. Razor Making-. All things con- sidered, perhaps a razor is the choicest article of cutlery, owing to the precautions necessary to pro- duce a keen edge. The blades ought to be made of highly-carbonated cast steel. The peculiar curvatures are produced by a nice adjustment of the forging process, with ham- mer, anvil, and swages selected ac- cordingly. When forged, the blade is smithed or cold-hammered, to in- crease the density ; and then slightly ground on a dry, coarse gritstone. When drilled, stamped, hardened, and tempered, it is ground wet on a fine stone varying between 4 and 12 inches in diameter, the smallest diameter giving the deepest curva- ture to the sides of the blade, and the largest the shallowest; about 6 or 8 inches impart the best combina- tion of fineness with firmness of edge. The thickness of the back of the razor, and the concavity of the sides, are so adjusted as to give an angle of about 18 to the cutting edge. The hardening or annealing of the blade is noticed under TEM- PERING, while the final processes are treated under POLISHING. The making of the handle varies in its REA 307 REG mechanical processes according to the material employed, and calls for no special notice here. Reaping- Machine is one of those agricultural machines in which the travelling of a vehicle over a field works the apparatus itself. Instead of using a hand-sickle or scythe to cut down ripe corn, a kind of double saw is used, one set of teeth gliding to and fro over another set, like the blades of scissors, catching the corn-stalks between them, and cut- ting them. Other reaping machines have the cutting edges arranged in different ways ; but in every case the wheels of the machine, drawn over the field by horses, give action to the cutting knives or saws. The reaping machines invented by Bell, Hussey, M'Cormick, and others, are now largely used in Great Britain, but still more extensively in America. Beatifying;. (See DISTILLING.) Red Lead is one of the oxides of lead, very useful as a paint or pig- ment. By exposing Litharge (which see) for a long time to the action of the air at a temperature of 570 Fahr., it is changed from a protoxide to a red oxide, which obtains the name of red-lead. As it is used as a sub- stitute for vermilion, its value de- pends greatly on its brilliancy ; the best, called orange mine, is made from carbonate of lead instead of litharge, and at a higher tempera- ture. Red Paints and Pigments. As will be seen noticed under various headings, red pigments, stains, and dyes are derived from a great num- ber of sources, including -vermilion, chrome red, Indian red, red-lead, red ochre, cochineal, &c. (See also DYE DRUGS.) Reed. The tall grassy plants known as reeds have given name to the mouth-pieces of oboes, cla- rionets, and bassoons, which are mostly constructed of some kind of med. Reeds are also employed in making walking-sticks and fishing- rods. For the metal vibrating reeds of certain musical instruments see HARMONIUM; ORGAN, CHURCH. There is also an apparatus called the reed in the weaver's loom. (See LOOM, HAND and MACHINE; WEAVING.) Refining- ; Refining- Furnaces. A refining furnace, such as is used in the iron manufacture, is generally built on a strong square platform of brick, elevated only a short distance above the ground ; the hearth being 3 or 4 feet long or deep by some- what less in width. This hearth or furnace-bed is formed of gritstone or clay-sand, and is slightly inclined from the back downwards towards the front ; the sides are formed of hollow cast-iron walls, admitting a stream of cold water to prevent them from being injured by the intense heat. Six tuyeres, three on either side, admit the nozzles of six pipes, which bring condensed air from a blowing machine, and direct it ob- liquely downward towards the hearth or floor of the furnace. The tuyeres, as well as the walls of the furnace, are cooled by a stream of water. About 400 cubic feet of air per minute are thus forced in. Over the hearth is a chimney 15 to 20 feet high 1 . A tapping-hole beneath the front of the hearth affords a place of exit for the molten iron. The whole arrangement is such as to bring an intense heat to bear on the contents of the furnace. (See IRON.) The smelting operations for copper, lead, tin, zinc, &c., always comprise some kind of refining. Refrigerator. (See BREWING; COOLERS, COOLING; FREEZING, &c.) Regenerative Furnace. This important invention, by Messrs. Siemens, has for its chief object the economising of heat, and therefore of time and fuel. There is much heat wasted in metallurgic pro- cesses, which it is believed might be partially saved by a better ar- REG 308 RES rangement of furnaces and flues. Siemens' plan is to arrest the heat which is escaping up the chimney, and to compel it to render useful service. There is an apparatus called the regenerator, placed somewhere near and between the furnace and the chimney; it is a chamber contain- ing a number of pieces of fire-brick or some other refractory substance. The heated air of the furnace, before passing into the chimney, passes through this chamber, and gives off to the fire-brick so much of its heat as to become nearly cool. The chamber becomes thus a secondary storehouse of heat, practically avail- able. The method of insuring these results begins by the use of a gas- producer, in which coal is distilled to the state of a rough, unpurified gas. During the roasting or burn- ing of the coal in this apparatus, water, ammonia, carbonic acid, and some other gases are driven off, and the remaining carbonaceous matter is mostly converted into the gas which is the object of the pro- cess. The gas,- when made, carries with it a heat of 350 Fahr. into the heating chambers, from which it proceeds to a regenerator. Fresh air enters another regenerator, and the air and gas then mix. The re- generators, already heated, give up their heat to this mixture, and the furnace is then fed with warm air instead of cold. The heated pro- ducts of combustion pass off into other regenerators, so that there is a continuous reproduction of results the regenerators saving the heat which would otherwise go off at the chimney, and applying it to heat the air which feeds the furnace. The furnaces to which the system is most applicable are those wherein a very high temperature is required. The gas-producers, placed at some dis- tance from the furnaces, may be made to supply gas for many of them at once, for smelting, pud- dling, melting, welding, &c. Be- sides its use in economising heat, a more intense heat than ordinary may be insured by this apparatus when wanted, and yet under remark- ably easy control ; there is also a lessening of the smoke and dust so usual with ordinary furnaces. There is a blast furnace at Feny Hill, Durham, 105 feet high by 28 feet in diameter, with four large blast- engines worked on the regenerative system. RegTilus is an old-fashioned name, now nearly out of use, for a metal in an intermediate stage between crude I ore and pure metal during the smelting and refining. Reisner Work. A kind of Buhl Work (which see). Rennet. (See CHEESE MAKING.) Repouss^Work, in artistic metal manufactures, is a kind of embossing. Sheet metal is hammered up at the back, so as to produce a raised de- vice on the front surface, which is afterwards finished by chasing. Benvenuto Cellini was a famous worker in this art, in gold, silver, and cheaper metals. The Birmingham manufacturers produce cheap but attractive teapots and coffee-pots by hammering up or repousseing pewter and Britannia metal, chasing the surface, and electro-silvering. There are, however, higher-class specimens of repousse-work now produced in Birmingham as well as in London. The International Exhibition showed this in the shield in repousse by Angell; the table and competition ' cups by Elkington ; and the magnifi- ' cent repousse shield and vase exe- cuted by Antoine Vechte for Hunt and Roskell. Resins constitute a large class of substances very valuable in the arts, and derived from vegetable sources. For the most part they are solid at ordinary temperatures, melt easily, burn with a white smoky flame, and dissolve in many of the ethers and oils. Copal, lac, mastic, sandarac, RET 309 RIB benzoin, guaiacum, turpentine, storax, copaiva all are regarded as resins. The common rosin of the shops is the resinous deposit from common turpentine after distilling. Some of the substances named under GUM are often called gum resins. Retort. In gas-lighting the dis- tillation of the coal takes place in retorts. These are vessels which will bear a great heat within and without. They are usually made of cast-iron, 7 or 8 feet long, by I foot in diameter. They are placed hori- zontally, with a mouth opening at one end to the air, and a body ex- posed to heat. The fuel is thrown in through a door at the mouth, secured by a screw and holdfast. Va- rious sectional forms are given to the retort circular, semicircular, oval, kidney-shaped, &c. to determine which produces the greatest quantity of gas in a given time from a given quantity of coal. Some of the great gas-works contain 500 or 600 retorts all of which are not wanted in summer fed with 100 Ibs. to 150 Ibs. of coal each every six hours. In consequence of recent improve- ments, retorts are now sometimes made of fire-clay instead of iron ; and these, as well as the iron retorts, have in some cases been made as much as 19 feet long. The clay re- torts bear a higher heat than those of iron. These very long retorts are double, having mouths at both ends. Reverberatory Furnace. (See the names of the principal metals, in the smelting of' which such fur- naces are employed.) The principle of construction is, that the fuel and the metal shall not be in contact, and yet that the flame of the former shall reach the latter. Revolver. This is the abbrevi- ated name for a revolving pistol or musket, usually the former. Ordi- nary weapons have one lock and one stock to one barrel; but a revolver has multiple power within a com- paratively small space, since it will . fire two or more times with one load- ing. The double-barrel weapon is not a revolver, seeing that the latter has only one barrel. Colonel Colt introduced beautiful revolver pistols in 1835, since which time Messrs. Deane, Messrs. Adams, and other inventors have produced many novel- ties in detail. The first attempts were with two or more barrels ; but it is now found that a single barrel may be made to do all the work. There is a steel chamber or breech, pierced through and through with cylindrical bores, each to receive a charge. The breech revolves or rotates, bringing each bore in turn into a line with the barrel. The breech makes one-sixth of a revolu- tion after each discharge ; it has six nipples for as many percussion caps ; but all the caps are acted upon by the same trigger and hammer. The principle is, as we have said, adopted mostly in pistols ; but there are also repeating or revolving rifles, such as Spencer's, with wonderful elaboration of detail. Attempts have even been made to apply it to large cannon. (See further under SMALL ARMS.) Rhodium, an intensely hard metal of the platinum class, is occasionally employed in small pieces in the arts ; but its great costliness, and the difficulty of working it, combine to limit its serviceableness. Ribbon Manufacture. A rib- bon is usually a long narrow silken fabric, although it may be made of other materials. English silk goods of the ribbon class preceded the broad silks, and have come to be gradually centred at Coventry as the chief seat of manufacture. The trade is managed a good deal in the same way as the framework-knitting or hosiery trade of Nottingham and Leicester, so far as regards hand -looms; but the power-loom system has necessitated the introduction of the factory ar- rangements, as in most other branches of weaving. The ribbon-loom is RIC 310 RTF more complicated than the ordinary loom, seeing that it has provisions for weaving several ribbons at once. One form is called the Dutch engine- loom, another the bar-loom ; while the steam-power looms have nume- rous beautiful contrivances about them. The Jacquard Machine (which see) is employed in weaving the more complicated patterns. By the adherence to an old rule, which once had a meaning, but now has none, English ribbons are named by pence as twopenny ribbons, twelvepenny ribbons; names which probably once denoted -values, but which now only denote widths. Various other names are given to ribbons, dependent on numerous circumstances relating to quality and appearance such as sarsenet, lutestring, satin, taffety, love, chine, watered, &c. ; also ribbon -velvet, galloon, and ferret. French ribbons still take the lead in the market, but Coventry is making strenuous exertions to rise to a level with them. There was lately an estimate that 6,000 persons were en- gaged in the ribbon trade at Coven- try. Messrs. Ormerod have devised a mode of producing useful cotton- printed ribbons ; they are very cheap and tasteful, and take printing better than silk. A mixture of silk and wool has been applied in a some- what similar way. The Swiss are trying their skill in what are called autophyte ribbons, printed by the application of photography to the etching of zinc plates, and producing a kind of lace pattern by this means. Bice; Bice Hill. The grain or seed of rice, one of the most abun- dant kinds of human food, is used by the Japanese tb ferment into a kind of beer called saki ; by the Chinese to produce a sort of rice wine ; by the Hindoos to distil into their favourite spirit, arrack ; by our distillers to add to the malt and corn in their stills ; by our makers of patent starch for muslin manufac- turers ; and by our cattle-food makers to produce rice-meal and rice-dust ; while the stalks are used in straw- plaiting. But boiled or baked food is the form in which rice is best known to us. Rice in the husk is called paddy. In India and China the husk is rubbed off by a kind of pestle and mortar ; but this is better done by the rice-mill, in which stones or rollers are so applied as to rub off the husk without breaking the grain. Rifle; Rifling-. Irrespectively of the size and shape of the weapon, rifling is a distinct principle of marked peculiarity, whether applied to muskets or to large ordnance. A smooth bore denotes its own charac- ter. A rifle is distinguished from it by having twisted grooves from one end to the other of the interior of the barrel. The object is as follows : If a bullet is so shaped that it must necessarily pass into the grooves, it cannot advance along the barrel with- out following the twist of the grooves ; it rotates on its axis while thus twist- ing, and this rotation makes the flight more straight and true than it would otherwise be. Three centu- ries and a half ago this principle was adopted in a rough kind of hand- gun made in Germany; and many inventions of analogous kind were put forth in the seventeenth and eighteenth centuries. A few troops called sharpshooters were armed with rifled muskets about half a century ago ; but it was not until quite recent times that European infantry began to be regtilarly sup- plied with such arms. Delvigne, Thouvenin, Mini4, Greener, Whit- worth, Lancaster, Richards, Terry, Snider, and other inventors have gradually brought the system to great perfection. The number of grooves, the shape and size of the grooves, and the sharpness of twist vary greatly ; and it is not yet known whether any one combination is the best, each inventor claiming excel- lence for his own. Lancaster's RIG HOC rifling is peculiar, seeing that it consists in making the bore oval, the oval itself twisting round in the bar- rel. Whitworth's is also peculiar, a hexagon being substituted for an oval. Large cannon are treated nearly in the same way as small arms, being rifled to obtain great range and accuracy. Rifled cannon were known so far back as two centuries and a half ago ; but they were not regularly adopted until the success of rifled muskets had been proved. Montigny,Cavalli, Armstrong, Whit- worth, Blakesley, Lancaster, Brit- ten, Frazer, Mackay, and Palliser are among the chief inventors in this art. The Armstrong Gun (vrhich see) is remarkable for the large number of small grooves. Very varied plans are adopted for com- pelling the ball and bullets to enter the grooves of rifled cannon and muskets. What is called the shunt, or shunt rifling, arises thus. If a ball exactly fitted the bore, it would be so tight that the cannon could hardly be loaded ; if it does not exactly fit it, the ball will rest on the lower half of the bore, the axis of the projectile will not be coincident with that of the gun, and the shooting will be inaccurate. Sir W. G. Arm- strong thereupon invented a beautiful contrivance for enabling the shot to shunt itself into the axis just before it leaves the gun. The mechanism for rifling, with or without the shunt arrangement, ranks in the highest class of our machine-tool achieve- ments. The rifling of the barrel and the loading at the breech are two dis- tinct matters. A rifle may either be a muzzle-loader or a breech-loader ; a breech-loader may either be a rifle or a smooth bore. Rigging- is a general name for the ropes of a ship ; standing rigging being those ropes which maintain the masts and bowsprits, and run- ning rigging those which work the sails and yards. Rivets ; Riveting- Machine. A rivet is simply a short piece of rod-iron passed through a hole in two overlapping plates, and ham- mered at the ends ; the projecting heads made by the hammering bind the two plates together very tightly, especially if the rivet be hammered while red-hot. Such rivets are now used in immense number where sheet-iron and plate-iron are em- ployed for tubular bridges, railway girders, station roofs, &c. In the Menai tubular bridge there are up- wards of 2,000,000 rivets, each of which required a dozen blows from a ponderous hammer ; and the vast station roof of the Midland Rail- way at St. Pancras is another exam- ple of a structure held together almost entirely by rivets. Rivet holes are usually made by the very efficient punching machine ; but it is not yet decided whether punching or drilling is the better plan. Where the position will admit of it, a rivet- ing machine is employed to press a lever forcibly against one end of the rivet while the hammer acts upon the other ; in some machines the rivet is squeezed into place. Roads. Under PAVEMENT, PAVING STONES, the foot-ways for the streets of towns are noticed; and under MACADAMISED ROADS the paving of carriage-ways with small broken stone. Macadam had a soft and yielding foundation un- der the broken stone of his road; Hughes advocates a foundation of gravel and lime ; while Telford in- sisted upon a solid foundation of squared granite stones, with a layer of broken stones on the surface. Granite is found to be the best stone for roads ; flint being too brittle, sandstone too soft, and limestone too easily acted upon by moisture. Rock Boring, or Machine Tun- nelling, is the drilling of holes by steam or water power to receive the charges for blasting. The most re- markable example hitherto known is the boring of the magnificent ROC 3 tunnel for the Mont Cenis railway. This tunnel will be nearly eight miles long; and as the mountain over it is too lofty to permit of the sinking of vertical shafts, all the workings have to be conducted from the two ends. The rock is mostly very hard, and the boring is difficult. The tools are worked by compressed air, and the air is compressed by water power. Water descends an inclined tube to an air-compressing room, where there are several com- pressors, each of which comprises mechanism that will drive air at a great pressure into large iron re- ceivers. The air in the receivers, at 90 Ibs. pressure per square inch, is conveyed in flexible tubes along the j tunnel, to the point where the work- | ing is going on. At this point are ten or twelve perforating machines, each capable of being moved to and fro on a tramway laid on a platform. Jumpers, or boring-rods, are worked with great rapidity horizontally, striking the face of the rock, and then rebounding, by an intermittent action of compressed air behind them. A hole about 2\ feet deep is pierced in forty-five minutes. Some portions of the rock, of quartz and crystallised schist, are exces- sively hard ; and in this case the holes are not pierced to so great a depth. Each jumper gives three blows per second, and makes one- eighteenth of a twist or revolution at each blow, or a complete revolu- tion in six seconds, thereby abrad- ing the rock more effectually. The jumper gives 1,800 blows in a mi- nute, with a force which is estimated at 1 80 Ibs. ; it wears out so rapidly under this severe ordeal, that a con- stant reserve of machinery and tools is required to be kept. A second flexible tube injects water into the hole after each blow, to clear away the debris. The holes are used for the insertion of gunpowder, to shatter the substance of the inter- mediate rock by explosion (as ex- 5 ROL plained under BLASTING). A blast of fresh air is then driven in by the compressing engines, to remove the smoke and freshen the atmosphere of the tunnel ; workmen approach to remove the fragments of rock, and carry them along a tramway to the mouth of the tunnel ; and then matters are ready for a further use of the perforating machine. There are other machines in operation for this kind of work Delviny's, Haupt's, and Lowe's all having their special characteristics. Rock Crystal. (See QUARTZ.) Rocket is a tube of pasteboard or of metal, filled with a mixture of saltpetre, sulphur, and charcoal, and fastened to a rod or stick. When ignited at the rear end, the forcible issue of explosive sparks drives the rocket by reaction in the opposite direction. According to the size and construction, rockets are used for war, for signals, for life-ropes, and for mere pyrotechny. When used as a life-saving apparatus, a rope or line is fastened to the rocket ; and when the latter is fired from the beach towards a stranded ship, the rope may be caught by the crew, and used as a means of escape. Dennett's life-rockets, improved by Colonel Boxer, are now used at up- wards of 200 stations on the British coasts, the rockets themselves being made at Woolwich laboratory. Rock OU. (See NAPHTHA ; PE- TROLEUM.) Rock Salt. (See SALT.) Rolling MiU. The rolling or milling of metals is one of the most important inventions connected with metallurgy, seeing that, besides con- densing the metal by intense pres- sure, the mill brings it into the shape of rods, bars, plates, or sheets, as may be needed. The action depends upon cylindrical rollers, placed hori- zontally one over the other at a short distance apart, and revolving in opposite directions ; they draw the metal in between them K and ROL 313 ROO in so doing reduce its thickness. If the surface of each cylinder is smooth and regular, the pair are suitable for sheets and plates ; but if they are grooved at right angles to the axis, they are adapted for rods and bars of various kinds, ac- cording as the grooves are circular, square, triangular, &c. In the roughing rolls, used in the iron manufacture, the two rolls of each pair are heavy iron masses, capable of being adjusted at various dis- tances apart ; they are usually about 5 feet long by 1 8 inches in diameter, and have a small number of large grooves elliptical in shape. The finishing rolls, in the same manu- facture, are similar in action, but are grooved differently, adjusted more accurately, and driven at a speed of 150 to 250 revolutions per minute, instead of 70 or 80. The largest rolls hitherto used are those employed in making armour plates for iron-clad ships. Rolling Stock. There is, per- haps, no better test of the vastness of the railway system of the United Kingdom, in its present state of de- velopment, than the item called rolling stock. This is a collective name for all the vehicles employed on all the railways, including pas- senger carriages, mail and parcel vans, luggage and break vans, wag- gons and trucks of every descrip- tion. Engines and tenders are not included, they being placed to the account of locomotive stock. It has been computed that, when the length of passenger railway opened for traffic in the United Kingdom had risen to 13,000 miles, there were 7,500 locomotives employed in draw- ing 18,000 passenger carriages and 235,000 waggons and trucks. The carriages and waggons had cost ;i 7,000,000, and the annual depre- ciation by wear and tear was ,1,250,000. Roman Cement is one of the class which consists mainly of argillaceous limestone, a natural combination of limestone and clay, calcined. Seventy or eighty years ago Mr. Parker in- troduced Roman cement, sometimes called, after him, Parker's cement, made from certain nodules found in the Isle of Sheppey ; these he calcined, crushed, and ground. The Romans are known to have used hard water- resisting cements made of some such substances as this, and hence the name. Other formations of the same kind of limestone have led to the mak- ing of many new cements in various parts of England; such as Frost's, Atkinson's, Medina, &c. When the limestone contains less than 10 per cent, of clay, the cement made from it is not hydraulic or water- resisting ; when the clay is more than 30 per cent., the mixture does not form a true cement at all : the useful preparations vary from 10 to 30 per cent, of clay. In calcining the cement stones or argillaceous limestone, the heat employed is only just sufficient to drive off the water and the carbonic acid. It is done in conical kilns, with coal or coke ;\s fuel ; and the stone loses about one- third its weight in the process. The calcined stone is ground in a mill, and packed in tight casks. The lightest and finest powder forms the best cement. In making cement from this powder, about one-third its volume of water is added, and the mixture is well beaten up. It sets very quickly after using. The septaria, or nodules of argillaceous limestone, found near Harwich, are said to yield us more than 2,000,000 bushels of Roman cement yearly. Roof. A timber roof is made up of those numerous pieces of wood noticed under CARPENTRY such as girders, struts, trusses, wall plates, rafters, tie beams, purlines, pole plates, king posts, queen posts, braces, straining beams and cills, ridge-pieces, collars, camber beams, &c. It is the practical solution of a problem, how to cover a large area ROO ROP by means of comparatively short pieces of wood, arranged some hori- zontally, some vertically, and some diagonally. In fact, a large and well- constructed timber roof is perhaps the best example of carpentry the distribution of pressure among the parts most able to bear it. Roofs, Iron. The use of iron roofs in large buildings is rapidly ex- tending, on account of certain ad- vantages attending them ; among which are their greater durability, greater dryness, and greater light- ness, both in appearance and in weight. The framing is of iron bars of various sections or contours, while the covering consists of galvanised sheets of iron. The sheets are usually of those thicknesses known in the tradeasNo. i8toNo.22. Corrugated zinc roofs are more costly than those of iron, but have certain advantages. A factory roof, with ridge principals, framing, skylight framing, gutters, and rain-water pipes, costs per 100 square feet of ground covered ac- cording to the span. Mr. Cola gives the cost for a span of 30 feet at S"j 5J. per 100 square feet ; whereas for one of 150 feet it is just double, and intermediate spans in pro- portion. A corrugated iron roof, which will support itself without any other framing than tie-rods and sus- pension-rods, is cheaper, and will suffice for smaller spans. From 25 to 40 feet span, the cost ranges from 2 15-r. to 4 2s. per IOO square feet if the sheets are painted, and from j3 ioj. to /5 if they are galvanised. The greatest work ever yet con- structed, in the form of an iron roof unsupported by pillars, is the roof of the new Midland Station at St. Pancras. Hope Making. Although chain cables have nearly superseded the larger kinds of hempen cables for ships, no substance has ever yet been found better than hempen fibre for making the numerous varieties of string, twine, cordage, ropes, haw- sers, &c. Every rope, whether large or small, has a continuous twisting of fibres one around another, like yarn and thread ; but the number of fibres is almost indefinitely greater, and a twist in one direction often covers or envelops a twist in another. Although we are most accustomed to hemp as the material employed, yet the same mechanical system of twist- ing would equally make rope of the fibres of sunn, jute, flax, grass, and reeds of various kinds ; hair and wool would also suffice, as well as strips of any kind of leather, hide, skin, and membrane. The natives of countries very little raised above barbarism readily find out these facts for themselves. The rope manu- facture is conducted on two different systems by hand and by machine. (I.) Rope Walk. The majority of cordage is made in a rope-walk. This is a strip of ground from 600 to 1,200 feet long. At one end, called the head of the walk, is a peculiar spinning-wheel, provided with small rollers and hooks, which the turning of the wheel causes to rotate with great rapidity. Posts are set up on both sides of the walks equidistant ; a horizontal bar or rafter connects the tops of each pair of posts ; and hooks are driven into these rafters. There is a pathway be- tween the two rows of posts, extend- ing from end to end, or from head to foot, of the walk. In this rope-walk the processes are as follow: (a.) Spinning. The hemp is heckled, to separate and straighten the fibres, in a way similar to that described under FLAX PREPARATION. It is with this heckled hemp that the spinner operates. He wraps round his body a bundle of hemp, with the bight, or double, in front. He draws out a few fibres with his fingers, sufficient for the thickness of yarn he is about to make, and attaches them to one of the whirl-hooks of the spinning-wheel. While an at- tendant rotates the wheel, and with v^ OF THE r UNIVERSITY it the hook, the spinner walks back along the whole length of the path. Two processes are thus carried on simultaneously ; the spinner draws out new fibres from his bundle, to make one continuous length out of several, while the wheel-turner gives a twist to the yarn thus made. The degree of twist depends on the re- lation between the speed of the spin- ner and the velocity of the wheel- turning. The spinner's real rate of walking backwards is about two miles an hour. Much manual dex- terity is required to draw out the libres so regularly as to make the yarn equally thick in all parts. The yarn, as it is made, is hung upon the hooks on the cross-beams. Several spinners may be at work in the same walk at the same time. The finished yarn is wound upon a reel. A good spinner will make nine miles of yarn in a day, and has to walk eighteen miles in making it ; the yarn varies from -|- to -j 3 ;/ inch in diameter, and weighs from 2\ to 4 Ibs. per 160 fathoms, or 960 feet. In some esta- blishments the yarns are spun by machinery; the hemp is heckled, drawn, doubled, and spun by pro- cesses not differing greatly from those employed in the flax manufacture. (&.) Tarring. Some yarns are tarred before being made into rope. To effect this, the yarns are warped into a hank or group of 300 or 400, dipped into tar heated to 2 1 2 Fahr. , and passed through a hole which presses the tar into the substance of the yarn, at the same time expel- ling the superfluous portion. Tarring enables a rope to resist wet, but is found to weaken the fibres some- what, (c.) Strand-laying. A thick rope is built up by degrees. The first stage is the grouping of fibres into a yarn, and now several yarns are to be grouped into a strand. A proper number of yarns being selected, and laid side by side, they are twisted one around another in a di- rection contrary to the twist of the individual yarns. This twisting is effected in the laying-walk (which may be the same length as the spin- ning-walk) by the aid of a tackle board, wheel, winch, and movable sledge, (d.) Hawser-laying. Sup- posing three strands make a rope, it is so managed that the twist shall be in the same direction as that of the fibres in the yarn, and in the opposite direction to that of the yarns in the strand. A block of wood called a top, with three deep grooves along its curved surface, is so placed horizontally that the three strands dip into or occupy the three grooves. A constant turning round of this top by a man who has the management of it, aided by mechanism to which the two ends of the strands are attached, causes the strands to be twisted very tightly one round another. The strands are reduced about one-third in length by this twisting, for they twist or pass round at an angle of 35 or 40. If the strands be three in number, as here supposed, the rope is said to be hawser-laid ; if four, sh roud hawser-laid, (e.) Cable- laying. One more stage in this accu- mulating of hempen fibres is cable- laying, in which three hawser-laid ropes are twisted round one another. Here, again, the direction of the twist is reversed, to counteract any tend- ency to untwist. This cable-laying is not now adopted for ropes of very large size, because iron chain cables are used instead ; but as the cable structure is very hard and compact, and well adapted to resist theentrance of water, smaller ropes are some- times made in this way. In such a rope, then, fibres are twisted into a yarn, yarns into a strand, strands into a hawser, and hawsers into a cable. (/.) Plaited and Flat Ropes. Cordage which is required to be pliable, such as clock-lines and sash-lines, is often made by plaiting instead of twisting. Many of the flat ropes used in min- ingare made by fasteninground ropes side by side by some sort of sew- ROS RUS ing or intertwining. (2.) Huddarfs Rope Machinery. The late Captain Huddart, about the year 1805, in- vented a very elaborate and beautiful series of machines for dispensing altogether with long rope-walks, and substituting as much as possible steam power for manual power in the several processes. Many im- provements have since been made ; but the principle of Huddart's ma- chinery is still maintained. The ma- chines, taking them collectively, comprise a number of separate parts spindles, spinning tables, revolv- ing drums, bobbins, reels, register plates, register tubes, compressing dies, spool frames, rollers, &c. Coil- ing or twisting is the primary work effected by these several machines ; and a vast amount of whirling there is to bring it about. The movements of the wheels, drums, bobbins, &c., are in some cases very curious ; quite an orrery of planets revolving round suns, and satellites revolving round planets. The most scientific part of the whole is a registering machine, intended to insure that the outer parts of a rope may not be more strained than the inner. Our manu- facturers, after supplying home de- mands, exported 113,000 cwt. of rope in 1867. (See also WIRE ROPES.) Rose. Besides the preparation of rose syrup, rose water, rose vinegar, and conserve of roses, there is obtained from this beautiful flower the costly substance noticed under OTTO. Rose Engine; Engine Turn- ing:. (See TURNING.) Rosewood. Our supply of this beautiful wood is mostly obtained from Brazil, in logs or half-trunks about 10 feet long. Some of the East India rosewood yields planks as much as 4 feet wide. Rosin. (See RESINS ; TURPEN- TINE.) Our manufacturers use up no less than 700,000 cwt. of this sub- stance in a year. Rotten-stone is a soft brown mineral, found in Derbyshire and other places ; when scraped to pow- der, it is useful for polishing metals. Rouge. The rouge used by jewellers is made from sulphate of iron, and is valued for its polishing quality. The rouge of the perfumer is an elaborate preparation from saf- flower and other substances. Roug-h Cast is a mixture of coarse plaster and gravel, applied to some kinds of brickwork. Rubble. (See MASONRY.) Ruby. The best varieties of this beautiful red gem are brought from Eastern Asia. It ranks next in value to the diamond and the sapphire. Small bits of ruby are much used in jewelling watches, and they have occasionally been employed as pen nibs. Rudder is the part of the helm of a ship which dips into the water ; it is hinged to the stern-post, and worked by the tiller, under a great diversity of arrangements. Rumble is a rotating cylinder in which articles polish one another by mutual attrition. Needles, pins, but- tons, shot, &c., are often polished in this way. A gigantic rumble is in use in Sheerness Dockyard, to rub the rust off chain cables. Rum. This spirit, so largely con- sumed by sailors, is made from the cane-sugar of the West India planta- tions. The skimmings of the sugar- pan give the best, and the molasses the worst. The fermentation and dis- tillation are conducted nearly in the same way as described under DIS- TILLING. Pure rum has nothing added to it but a colouring of brown sugar; but fancy kinds are flavoured with pine-apples and guavas. The quantity of rum entered for home consumption in 1867 was 4,314,000 proof gallons. Rushes are used extensively for chair-bottoms, mats, baskets, rush- lights, coarse bandages for hayricks, &c. RYE '. "Rye is not much grown in Eng- land ; but in the North of Europe it is largely cultivated for bread (which 7 SAF is very wholesome), for distilling into Hollands, and for straw-plait manufacture. s. Sabots, or wooden shoes, are ! made in France and Belgium on a ; large scale, for the use of the pea- santry ; they are exposed to the smoke of burning wood to give them a red- dish colour. Saccharometer, used in deter- mining the strength of worts in brew- ing and distilling, is applied nearly in the same way as the Hydrometer (which see). Saddlery constitutes, with Har- ness Making, a particular branch of trade, in which leather is by far the most important material employed. The leather having been prepared by the tanner and currier, the work then consists chiefly in cutting and sewing of various kinds. A saddle has, however, a wooden frame or foundation, the leatherportionsbeing called the skirts, seat, girth, stirrup strap, and crupper loop. The seat is of pig-skin. The making of horses' collars (which are stuffed with straw) is a difficult part of harness-work. Saddlers' ironmongery of all kinds is made in the Walsall district in large quantity, and the leather-work also to a considerable extent. The Aus- tralians take pride in the advances which they are making in this art. During the visit of the Duke of Edin- burgh to Sydney, in 1868, saddles and harness of a high degree of ex- cellence were made for him in that city. We send out from ^200,000 to ^300,000 worth of saddlery and har- ness to various countries every year. Safes. (See FIRE-PROOFING.) Safety Cage. (See MINING LADDERS, MINERS' CAGE.) Safety Fuse. In mining and quarrying the gunpowder for the blast used to be fired with a train in a way that often led to accidents. Bick- ford's Miners' Safety Fuse was in- vented as an improvement. Thepo\\'- der is put into a cylinder, which- is wrapped round closely with hempen cord, then varnished and whitened. If the hole in the rock to be blasted is wet, a charge is put into a water- proof bag ; one end of the fuse is tied to its mouth ; it is thrust into the hole, and the fuse hanging out from the hole is easily fired. The fuse burns at the rate of 2 or 3 feet a minute. One advantage of this fuse is, that it may be used whether the hole is wet or dry. Safety Lamp. When sad ex- perience showed how dangerous an open candle is in a coal mine filled with fire-damp or explosive gases, ingenio'us'nien sough'tforsome means of averting the danger. At one time a sort of continuous flint-and-steel apparatus was adopted, to keep up a succession of sparks that would in some degree light up the mine ; but this has been superseded by the beau- tiful Safety-lamp. The invention was chiefly due to Sir Humphry Davy; but the practical develop- ment to George Stephenson and Dr. Clanny, followed by many other in- geniousmen. The principle of action is, that the inflammable gas of a coal mine (see FIRE DAMP), when kindled into a flame, will not pass through the meshes of a very fine iron-wire gauze ; the gas itself will pass when cold or non-ignited, but not as a heated flame. An oil lamp is placed within a gauze cylinder, having no openings except the meshes. Air easily enters to feed the flame. Fire- damp also easily enters, kindles, and fills the whole interior of the cage or cylinder with a blue flame ; but this flame cannot get out to kindle the SAF SAL great body of gas in the mine. The blue flame in the lamp is a warning to the miner that the air around him is very foul and dangerous. Any defect in the lamp, or any carelessness in his mode of using it, may lead to instant explosion, followed by death or terrible mutilation. The light is sometimes so dim as to tempt the miner to obtain an increase by open- ing the gauze door of the lamp a perilous practice, to avert which numerous forms of new lamps have been invented by Waring, Robin- son, Ogden, Muessler, and other in- ventors. An Electric Safety-lamp was tried at the Newcastle collieries in 1865, kept in action by a small electro-magnetic machine. It gave a very cool light, and was so far safe ; but the light was too faint for working, and the apparatus too heavy. Safety Valve in steam-boilers is a contrivance by which the steam can avert danger due to over-pres- sure. It is made in various ways ; but in every case the steam, when too elastic for safety, can open a valve for itself, and escape into the open air. Safflower is the corolla of a South European plant, extensively used in dyeing, printing, and paint- ing yellow. Sag-o is the starch of many kinds of palm, prepared from the pith of the stem by cutting down, splitting open, digging out the pith, washing, and subsiding. This produces sago flour, from which pearl sago is pre- pared by granulating. Sail Cloth. This strong and serviceable material is made of hemp, flax, jute, or cotton, or com- binations of them, according to cir- cumstances ; but the best sails are made of flax. Sail-cloth may be regarded as a medium in quality between linen and canvas. The fibre is well selected, the yarn well spun, and the cloth well woven ; for cheap sails may be a costly calamity at sea. The cloth is woven narrow, so that many widths are required "or even the smallest sail ; while the mainsail of a large ship has a prodigious amount of sewing and stitching to bring it to the proper size. Several kinds of sail-cloth are made in the Royal Navy, each distinguished by a particular num- ber, and having a certain definite weight per square foot ; they vary from 22 Ibs. to 44lbs. per bolt of 38 yards, 24 inches wide. The East Indiamen of past years used to spread 9,000 yards of canvas, and some of the American clippers have exceeded this quantity. The making of a sail comprises not merely the sewing of the several breadths together, but also the attaching to them of cords known as bolt ropes, foot ropes, head ropes, and leech ropes. Sal Ammoniac, the proper name for muriate of ammonia, is largely used in dyeing, in tinning, in sol- dering, and in other manufacturing arts. Salt. A salt, chemically con- sidered, is usually the result of the combination of an acid with an alkali, an earth, or a metallic oxide ; and is then called by such names as sulphate of potash, carbonate of lime, acetate of iron, and the like. In fami- liar language, however, salt means table, common, or culinary salt, so invaluable in cooking and in many of the arts. This used to be re- garded chemically as a muriate of soda, but is now known as chlo- ride of sodium. Salt is one of the ingredients in sea-water ; it also exists underground as rock-salt ; and when this rock-salt is found dissolved in the water of under- ground springs, the liquor obtains the name of brine. The value of salt as an antiseptic, as a means of salting or pickling meat, as a condi- ment or seasoning, and as a source whence soda may easily be obtained, is extremely great. Saltern is a place where salt is SAL 319 SAL obtained from sea- water, which con- tains 2 to 3 per cent, of this useful substance. A process of evapora- tion drives off the water, and leaves the salt in a crystalline state. Sea- water is admitted, at high tide, to a collecting -pond formed near the shore, and there stored to a depth of some feet. After depositing its mud, the water slowly travels from one shallow pool to another, eva- porating under the air and sunshine of summer weather from March to September ; it becomes more and more intensely salt brine as it pro- ceeds, until at length the salt fairly crystallises. The passage from one pond, pool, channel, or tank to another is govemed by plugs and sluices. The spent lye, when all the salt is crystallised out of the water, is allowed to flow back into the sea. In wet weather the eva- poration almost entirely ceases. The salt is impure, being impregnated with chloride of magnesium ; but this naturally separates under pro- per regulations. This, being the very simplest mode of obtaining salt, is largely practised in various parts of the world. Requiring no fuel for boilers or furnaces, the salt is made very cheaply. Notwith- standing this, however, the English salterns have been almost driven out of use by the much more rapid and effective system of the brine springs in Cheshire and Worcester- shire. A peculiar mode of making salt through the medium of sea- sand is practised in Normandy. Sea-sand, dredged up from the shore by a long broad scoop drawn along by a horse, is formed into a kind of filter, upon which sea-water is poured ; the filtration that ensues greatly strengthens the brine. Boil- ing over a wood fire gradually eva- porates the liquid ; coarse, impure salt results ; and this is made finer by further processes. Another pro- cess for obtaining salt from sea- water is by freezing. When sea- water partially freezes, the salt does not go into the ice, but remains in the unfrozen water, which conse- quently becomes salter than before, because the salt is concentrated within a smaller bulk. Natural brine is thus formed, which, by boiling and evaporating, gives up its salt in the form of crystals. Salt Mines. In some districts there are extensive beds of solid salt, at varying distances below ground ; and these are the scene of mining operations, having a distinct cha- racter of their own. The first of such beds discovered in England was about two centuries ago, near Northwich, in Cheshire ; and others in the same region have been discovered since. They lie at 100 to 200 feet below the surface, and are from 4 to 100 feet thick. In one place a bed of clay intervenes be- tween two beds of salt. The salt is of rocky hardness, more or less im- pregnated with earthy substances. Shafts are dug down from the sur- face ground to the bed, and lateral galleries spread out from these in all directions sometimes worked out in aisles, at others with massive blocks left to support the roof. A pick would suffice to dig the salt, but it is usual to expedite the pro- cess by blasting. The masses, vary- ing greatly in size and quality, are drawn up by steam power. This is crude rock-salt, which needs refin- ing processes before it can be applied to most useful purposes. These processes are described with others under SALT WORKS. Salt of Lemons, used for taking out iron moulds, is properly uxalate of potash. Saltpetre. (See NITRE.) Salt, Spirits of. This was the old name for what is now usually called muriatic acid. Salts, Smelling, are usually made of carbonate of ammonia, scented with some of the essential oils. Salt Works are large establish- SAL 320 SAN ments in which salt is obtained from rock-salt or from brine, and carried through all the processes of refining, Sec. Salt springs are now a more prolific source than any other. The brine, formed by the flowing of un- derground springs over beds of rock- salt, accumulates in large quantities, and, when pumped up, is at once ready for further processes. These subterranean reservoirs of brine are found in various parts of Cheshire and Worcestershire, from 30 to 200 feet or more below the surface. The springs have been worked almost as far back as the industrial history of England is known. The reservoir is often a lake of brine resting on a bed of salt. Shafts are dug down to the proper level ; in each shaft is an inner or concentric one ; the space between the two is puddled with well-rammed clay, and thus the lateral springs of fresh water are kept out. The brine is pumped up the shaft by ordinary means ; the pumps, in successive stages of the history of Cheshire, have been worked by manual, horse, wind, water, and steam power. If the brine, when collected in a reservoir, is not found to be fully saturated with salt, lumps of rock-salt are thrown in, to in- crease the richness. From "the reser- voirs the brine flows through pipes or troughs into evaporating pans, large oblong wrought-iron vessels from 12 to 1 6 inches deep. Three or four fires are kept burning under the pans to boil and evaporate the brine, and then the salt crystallises as it cools. The details of the pro- cess vary according to the kind of salt to be made, whether staved, common, flaky, at fishery. The size of the crystals of salt varies with the temperature of boiling and the details of crystallising. The fami- liar table-salt, brought to a beauti- ful white colour and considerable fineness, is formed into large quad- rangular blocks, which are dried in ovens at so high a temperature as to test severely the heat-enduring powers of the men employed. In France and Germany the processes differ in many ways from those in England; but all are equally de- pendent on the production of these two results to concentrate the brine by evaporation in heated boilers, and to allow the crystals of salt to form gradually in cool, quiet vessels. Large-grained salt is best fitted for salting and curing herrings and other fish, whereas small-grained has su- perior advantages for certain pur- poses. The make of salt in the United Kingdom is roughly estimated at 1,200,000 tons annually. The ex- port alone in 1867 was 720,000 tons. Sand, properly speaking, is veiy small particles of quartz, silica, or flint, though the name is sometimes given to other stony fragments. It results from the gradual decay of rocks, whether on the sea-shore or in sandstone districts ; and it owes its various colours chiefly to the vari- ous oxides of iron with which it is impregnated. The kinds differ in fineness or sharpness as well as in colour. Some or other of them are used in glass-making, sand-paper making, iron and brass founding, mortar and cement making, stone sawing and grinding, filtering, po- lishing dust, hour-glasses and egg- timers, and many other purposes in the arts. In general, river sand and pit sand are sharper than sea sand. Silver sand, a very fine sort, is of great value in glass-making. The dust worn off grindstones, and crushed road-material, are much used as substitutes for sand by the Sheffield cutlers and steel-workers. Sandal Wood is a beautiful, com- pact, fine-grained, fragrant wood, brought from the East Indies, and highly prized for small ornamental manufactures. Some kinds are made into pastils for odoriferous burning. Sandarac. This gum, or resin, exudes from a tree in North Africa ; it is a transparent yellowish sub- SAN 321 SAW stance, used in making varnishes and pounce. Sanders "Wood, sometimes con- founded with sandal wood, is a dark red wood used as a dye-stuff. Sandiver, a scum formed during glass-making, is used in some kinds of polishing powder. Sandstone, as a material for build- ing, is a curious kind of natural con- crete, being made up of small parti- cles of quartz or silex cemented with argillaccous.and calcareous matter. It is frequently laminated sometimes having little films or plates of mica parallel with the beds or layers. This accounts for the fact that sandstone, if built up with the laminae vertical, decays more quickly than if hori- zontal, for the layers in effect fall away one from another, or peel off. The particles of quartz or silex are virtually indestructible ; but the ce- menting matter is affected by air and moisture in a degree varying with different kinds of stone. Among well-known old structures built of some or other of the many kinds of sandstone may be mentioned Kccle- stone Abbey, the circular Keep of Barnard Castle, Tintern Abbey, Whitby Abbey, Ripon Cathedral, Rivaulx Abbey, the Keep of Rich- mond Castle, Durham Cathedral, Newcastle Church, Carlisle Cathe- dral, Kirkstall Abbey, Shaftesbury Church, some of the churches in Derby, the choir of Southwell Min- ster, and the ashlar-work of Spof- Ibrth Castle. SapanWood, brought from Singapore, is useful as a red dye. Sapphire. (See GEMS AND PRE- CIOUS STONES.) Sardines. The sardine fish, some- thing like the herring and pilchard, are mostly caught on the Atlantic and Mediterranean coasts. They are prepared for sale in enormous quantities washed, sprinkled with line salt, deprived of the head and entrails, washed again, dried in the fresh air, steeped in boiling oil, drained, put into tin boxes, the boxes filled up with oil, soldered, and ex- posed foratime to hot water or steam. Some are cured in red wine instead of oil. Many of the fish thus sold as sardines, however, are really sprats. Satin. In the silk manufacture, plain silks are woven by making the weft threads pass in regular order under and over the warp threads ; but in satin the weft is brought much more prominently to the surface, by passing over many more warp threads than it passes under. The fabric is more glossy and lustrous, but less durable, than plain silks. Satinet is a special kind of satin. Satin Wood. This beautiful wood for veneer and cabinet-work is brought chiefly from the Indies, in short logs 6 or 7 inches square. Sausage Machine, or Mincing Machine. This contrivance some- timesacts byakind of grinding move- ment, like a coffee-mill ; at others by a chopping action, like the tobacco- shredding machine. Saw ; Saw Making*. A saw is simply a thin piece of steel with the edge jagged or notched; yet its manu- facture requires close attention to a number of indispensable particulars. It ought to be of equal thickness and elasticity throughout ; it must have a toughness of metal and a form of teeth varying with the kind of sawing which is to be done by it ; and it should be equally ef- fective, however much the size and shape may vary. The kinds are very numerous. Those which have a handle at one end, and no stiffen- ing back, comprise hand, rip, half- rip, panel, table, lock, key-hole, and several others ; while, with handles at both ends, there are pit saws and cross-cut saws. Those which are strengthened at the back edge with brass or iron comprise tenon and dovetail saws, and others in which accurate work is required. Wood- cutters', ivory, buhl, and piercing saws are examples which have a Y SAW 322 SAW long thin blade stretched out tightly by means of some kind of bow or frame. The processes of making ai e as follow: (i.) Shearing. The land of steel having been selected, the sheets are cut up into pieces of suitable size. The shears for this purpose are usually faxed, one blade being used as a lever, and the other stationary. (2.) Teeth Cutting. The teeth of saws are made by cutting out small pieces of steel not, as in file-making, by simply depressing a groove. A punch makes the cut, and a fly-press impels the punch. The blade is shifted one tooth for- ward at a time, and there is a guide or gauge to insure that the teeth shall be equal-sized and equidistant. The punches vary greatly according to the size and shape of the teeth to be made. There are beautiful little saws for inlaying work, made of watch-spring, in which the width is only 3*5 inch, with fifty or sixty teeth to an inch. A peculiar shape of tooth is sometimes made by the suc- cessive blows with punches or chisels of different kinds, the second enlarg- ing or modifying the gap made by the first. (3.) Tempering. When the teeth are cut, the steel is hardened and tempered, to enable it to bear the usage to which it is to be exposed. Brought to a red-heat, the saws are plunged into a mixture of oil, tallow, suet, wax, resin, and pitch; this hardens them ; and then they are tempered by burning off some of the composition by heat, the tempering being modified in degree according to the kind of saw. (4.) Planishing. Rested on an anvil of polished steel, and hammered with a smooth-faced hammer, the metal is brought to an equable degree of density and hard- ness in all parts. (5.) Grinding. This is the employment concerning which the hideous disclosures were made in 1867, in connection with the Trade Union outrages at Sheffield. Not that there is anything in it lead- ing naturally to such malpractices ; but it so happens that one particu- lar body of men, the saw-grinders of Sheffield, have carried trade vio- lence to a more serious length than any other body of English workmen in recent times. The grinding of saws is dirty and heavy work. Grind- stones are used 5 to 7 feet in dia- meter, against the revolving edge of which the saws are laid flat, until a thin film of steel has been rubbed off, and the surface brought to a general level. There is some nicety in grinding the saw so that it shall be a little thicker at the toothed edge than at the back edge. (6.) Setting. The saw, when ground, is planished a second time, slightly heated over a coke fire, slightly ground again, smoothed upon a hard stone, and the teeth set. This setting consists in giving a bend to every tooth, the bending being towards the one and the other side alternately ; and it is done by blows from a hammer of peculiar shape. The teeth themselves are of various shapes, called peg, fleam, gullet, "briar, skip, and other names ; and the set given to each de- pends on the kind of work to which the saw is to be applied. (7.) Finishing. A few finishing processes of buffing on a glazer, planishing on a wooden block, and cleaning with emery, pre- pare the saw for the market. (For the saws worked by machinery see SAW MILL.) Other kinds of peculiar shape receive the names of trepanning, circular, curvilinear, drum saws, &c., for special kinds of work. Some of them are made up of several plates of steel screwed or riveted together, owing to the difficulty of bending one single piece of the proper size to the right shape. In cutting circu- lar discs of wood, felloes of wheels, backs of chairs, and backs of brushes, saws of peculiar shapes are needed. Sawdust Manufactures. New uses are frequently found for saw- dust in some branches or other of manufacture. Paper is made from it ; spirit is distilled from it ; and hi SAW 323 SCA some parts of Europe even bread is made of it. Sawdust is found to be so cheap and excellent as a source of oxalic acid, that all other modes of obtaining this chemical are now abandoned. A new manufacture has been established at Paris, called bois durci, or hardened wood, in which sawdust is employed in a very ingeni- ous way. The sawdust of hard kinds of wood, such as rosewood and ebony, is mixed into a paste with blood and other substances ; this paste, pressed into moulds, produces beautiful me- dallions and other small articles. Saw Mill is a frame in which saws can be worked more effectively than by hand ; wind and water power have both been used, but steam power is now generally adopted, (i.) Frame Saws. The simplest form of saw-mill for cutting timber into planks, has a horizontal bed with a longitudinal motion. Saws, from two to any greater number, are fixed vertically in a frame at regular dis- tances apart, the plane of each saw being parallel with the length of the timber. Two simultaneous move- ments are provided for by the mill gearing : the up-and-down motion of the frame which contains the saws, and the longitudinal motion of the bed on which the timber rests. As many parallel cuts are made in the timber as there are saws in the frame, and the timber travels onwards to meet the saws. In some cases as many as a dozen saws are working in one frame, each making 100 or more cuts per minute. The me- chanism of the frame has been im- proved in various ways by Brunei, Hick, and other inventors. (2.) Circular Saws. For many pur- poses a veiy effective arrangement is that of the circular saw. The saw is a circular disc, revolving on an axis which is usually horizontal ; and the wood to be sawed is pressed up against the teeth. The thickness of the saw, the set of the teeth, and the distance between them, all have to be adapted to the severe friction which these saws undergo during their continuous action. Smaller teeth and a lower velocity are needed for cutting hard wood than soft ; smaller teeth and higher velocity for cutting across the grain than with it. The saws with which veneers are usually cut (see VENEER) are the largest and most important examples of the cir- cular saw. Scaffolding:, as a mere succession of stages to support the workmen while building a house, is usually a very rough and simple affair. Fir poles from 20 to 50 feet in length, and of various thicknesses, are fastened together into a framework. The lower ends are inserted into the ground, or into tubs of earth ; the height is increased by tying the upper poles to the lower with ropes ; while the horizontal poles are either tied to the upright with ropes, or rest with one end in or on the brickwork. The horizontal pieces parallel with the wall are called ledgers, and those at right angles to the wall putlogs. Modern scaffolding, especially for large constructive works, is, however, a much more scientific matter. Squared timbers are used instead of poles ; and all the resources of car- pentry are brought to bear on the rearing of a framework that shall possess the maximum of strength with the minimum of material. Some of the scaffoldings seen in London within recent years have been al- most as remarkable as the buildings constructed by their aid witness those for the cupolas of the Inter- national Exhibition of 1862 ; for the Charing Cross and Cannon Street Station roofs of the South Eastern Railway Company ; and (grandest of all) for the Midland Railway Station roof at St. Pancras. Scag-liola, or artificial coloured marble, is made of very fine gypsum or plaster of Paris. The sifted pow- der, mixed with alum, isinglass, and colouring matter, is worked up into SCA 3 a paste, which is beaten down upon a prepared surface with small frag- ments of marble to make up a sort of breccia. Colours to imitate any particular kind of marble are mixed and painted somewhat in the manner of fresco ; and herein is the chief art to imitate successfully the ever- varying markings and veins. The surface is then rubbed with pumice- stone, with tripoli and charcoal, with tripoli and oil, and with oil alone, by which time a beautiful polish has been produced. Scarlet. (See COCHINEAL.) Schiedam. (See GENEVA.) Scissor Making*. This is a pe- culiar branch of cutlery-work. Cast- steel is used for the best kinds, shear steel for those in most general use ; large scissors and tailors' shears have steel blades with iron bows and shanks ; while the cheapest scissors are wholly of iron, some- times even of common iron, for the Indian and South American mar- kets. According as the scissors are cutting-out, drapers', flower, garden, grape, button-hole, horse-trimming, hair, lace, lamp, nail, paper, pocket, &c., so will they vary in the details of manufacture ; but an ordinary pair of household scissors is thus made : The end of a heated bar is forged into a blade, with an extra length for shank and bow ; a punch, hammer, and beck-iron are then used to fashion the bow, and by means of filing and rivet-hole boring, the shank is brought to the required form. The two pieces for each pair are selected, hardened, ground, glazed, polished, and put together by a rivet-screwer. What appears to be the flat side of a scissor-blade is really concave, and much art is shown in giving A cutting action to the two blades when adjusted. Whether scissors are ten guineas or one farthing per pair (and there are example's in both of these extremes), the peculiar action of the rivet joint must be maintained. \ SCR Scotch Boxes. There is a pecu- liar manufacture of snuff boxes and other small boxes in Scotland, re- markable for the perfection of the hinge and the close fitting of the cover. The wood employed is sycamore or plane tree ; and the box and cover are each cut in a curious way out of one piece. A number of circular excavations are made near together by means of a centre-bit or a lathe- drill. The interior is then squared out by means of gouges and chisels, and is afterwards smoothed with files and glass-paper. The hinge is formed partly out of the substance of the box, and partly out of that 01 the lid, great attention being paid to the accurate fitting of the various parts one into another. The box is lined in the inside with stout tinfoil, and is painted on the outside with several coats of colour. A pattern is in most cases produced, either by the hand of an artist or by mecha- nical means. The most usual pat- tern is of the tartan plaid, the lines of which are drawn separately by pens fixed in a ruling machine. Sometimes this is done on the box itself, sometimes on paper afterwards affixed to it. A more costly kind of adornment consists in coating the outside of the box with stout tinfoil, painting over this, and tracing or cutting into the foil an intricate pattern of curved and straight lines, by means of a sharp tool and a ruling machine. The bright tin is thus made visible be- neath the paint, and the surface is then highly varnished. Such boxes, and snuff boxes of other kinds, are largely made at Cumnock, Mauch- line, and Laurence Kirk. Screw Cutting*. The cutting of the worm or thread on a screw is now usually done by machinery. The iron or other metal is brought to the state of rod or thick wire. When straightened out from a coil, the rod is drawn into a machine, cut off to the proper length, struck at one SCR 325 SCR end to form the head, turned in a lathe to shape the head and neck, cut with a notch to receive the screw-driver, and wormed or cut with a thread along the shank. This last is the most important pro- cess of the whole, seeing that the cutting tool must travel longitudi- nally while the screw rotates, and that the pitch or diagonal of the thread must be accurately insured. A reverse operation to such as the above is necessary when an internal screw is to be made ; that is, when the thread is to wind round the interior of a cylinder instead of the exterior of a rod. A convex screw is often used as a tap or cutter for making an internal screw, and -vice versa, especially when the cutter works upon wood ; and dies and screw-nuts are used in a some- what similar way screw-boxes, die- stocks, and tap-plates being employed to aid in the processes. Some of the great engineering establishments have machines which will cut large screws accurately to any pitch from one pattern. Depending on greatly- varying circumstances, screws are designated external, internal, coarse, fine, right-hand, left-hand, double, triple, angular, square, round, binding, rgeulating, attachment, &c. At the Paris Exhibition, 1867, there was a very ingenious machine for making small screws. Different tools belonging to the same ma- chine perform operations in succes- sion on the same screw; they are fixed in a revolving holder, which turns after each operation, and then pre- sents a new tool to do another kind of cutting. Six of these operations, performed by six tools ranged around the holder, complete the screw. Screw Jack is an apparatus for lifting heavy weights through short distances. A winch-handle turns a toothed wheel; the pinion of the wheel works into the teeth of a vertical rack, and compels it to rise. The handle has to be turned several times before the rack can be raised even one inch ; but an immense power is thereby gained. Screw Pile. (See PILE ENGINE.) Screw Propeller. When Ar- chimedes invented the screw known by his name, he intended it as a means of raising water. He placed a screw within a cylinder, put the lower end of the apparatus diagonally in water, and made it revolve ; the water was drawn up by being compelled to follow the thread or worm of the screw. Sometimes there was a tube wound spirally round a central axis or shaft, instead of a screw within a cylinder. When once the principle of the Archimedean screw is under- stood, its fitness to produce motion as well as to raise water becomes apparent ; and hence the invention of the screw propeller for working steam-vessels. Mr. Woodcroft pa- tented an invention for this purpose in 1832 ; he was soon followed by Mr. Smith and Captain Ericsson ; then came Blaxland and Griffiths ; until at length every part of this subject has been elaborately studied. In a screw propeller the steam- engine causes a long horizontal shaft to rotate ; the stern end of this shaft has the propeller attached to it. The propeller is a kind of short screw, with from two to six blades project- ing from a central stem usually two orthree; eachbladehas very peculiar curvatures, calculated to give a screw- like appearance and action to the whole. When the longshaftis screw- ing itself through the water, the resist- ance offered by the broad surface of the blades causes a reaction, and this reaction drives the ship itself in the opposite direction. Engineers and nautical men are gradually coming to an agreement as to the relative merits of the screw propeller and the Paddle Wheel (which see). One vessel, called the Cigar Ship, has an enormous propeller, which com- bines some of the characteristics of scu 326 SEA the screw and the paddle. Some screws are auxiliary; that is, they are put out of gear when there is wind enough to pro- pel the ship by the sails. Some screws are double or twin, two screws having independent ac- tion, and offering great facilities for turning the ship about. In the screw-propeller apparatus made by Boulton and Watt for the Great Eastern, the propeller shaft is 160 feet long, and in some parts 24 inches thick ; the propeller is 24 feet in diameter, and the cylinders of the screw-engines are 84 inches diameter. Sculpture Apparatus. As one of the noblest of the fine arts, sculp- turelies, of course, beyond the scope of the present volume. Mechani- cally considered, a bronze statue requires an artist to make the clay model, and a metal-founder to do the rest. (See STATUE CASTING.) In executing a marble statue, the sculptor avails himself of strictly mechanical aids in determining the length, width, and depth of every cut he makes with his chisels. So purely mechanical, indeed, is much of this labour, that the sculptor, however inspired by genius, always employs subordinates to do much of the preliminary work. An instrument of the pantagraph land (see PAN- TAGRAPH) renders much useful aid in copying from the model to the marble. Another aid has recently been devised, called photo- sculpture, for copying from the life. M.Willeme has devised an arrange- ment for taking statuette likenesses of living persons, with photographs to assist the sculptor. A circular room is built, wholly of glass, above 8 feet from the ground, and having twenty-four apertures equidistant round the wall below the glass. The person stands or sits in the middle of the floor ; twenty-four photographs of him are taken by cameras in the apertures. The twenty-four pictures thus taken, from twenty-four points of view, are used in succession to guide the sculptor, who models his clay from them, with a pantagraph to trace the outlines. Seal Engraving is a special kind of Lapidary Work (which see). Sealing- "Wax. This combina- tion of wax and gum resin seems to have been invented in India, and introduced into France about two centuries ago. It was first made in England a century later. Curiously enough, Dutch sealing- wax at one time denoted the best kind, but now it denotes an in- ferior sort. All the higher-priced varieties are made of the best shel- lac and Venice turpentine, coloured red by vermilion, or black by ivory- black ; the cheaper kinds are made of inferior materials. The wax used for the Great Seal of England is made up according to a recipe kept in the Lord Chancellor's office ; it is a compound of oils and balsams, and has a whitish appearance. The wax of the Great Seal and the Privy Seal of Scotland is made of resin and bees'-wax, coloured with ver- milion. The Exchequer Seal is green. Charter wax, like that of the Great Seal of Scotland, can be melted for sealing at 118 Fahr. ; the finest red wax at 140 ; while that intended for India melts at 170. The addition of a little cam- phor improves the fusion. The melt- ing and mixing of the ingredients, and the shaping and polishing of the wax, are carefully-managed pro- cesses. Sea-weed. Many kinds of sea- weed are very useful in the arts. Some species of fucus yield a sub- stitute for isinglass. From dulse the Kamtschadales distil a spirituous liquor ; and it will also )ield kelp for soda. The stems of the tangle are made in the Orkneys into knife- handles. The weed called sea-lace in Norway is used for making fish- SEE 327 SEW ing lines. Irish moss yields excel- lent gelatine, useful in food and for stiffening silks. A seaweed found in Malay yields a varnish which renders paper transparent. The numerous applications of seaweed to food and beverages are far more important than any of the above. All kinds of seaweed are also valu- able as manures. Seeds. Besides home supply in many forms, there is a large im- portation of seeds from abroad, chiefly for pressing into oil. In 1867 we imported 1,100,000 quarters of linseed, 610,000 quarters of rape seed, 94,000 tons of cotton seed, and 150,000 cwt. of clover seed, besides smaller quantities of many other kinds. Segrg-ar is the name of thebaked- clay vessel in which articles of porce- lain and earthenware are enclosed before being placed in the oven or kiln. Semaphore. (See TELEGRAPH.) Sepia, a product of the cuttle- fish, is concerned in the preparation of some kinds of Ink (which see). Seraphine. ( See HARMONIUM. ) Serge is a thin kind of twilled worsted cloth. The name is also given to a coarse sort of twilled silk, occasionally used as a lining for men's coats. Serpentine is a species of stone, found chiefly in Cornwall, which is occasionally used for architectural and decorative purposes. It is a very beautiful marble, of moderate hardness, varied in colour, but mostly a rich dark olive-green, spotted with red and traversed by crimson and white veins. Obelisks, fonts, chimney-pieces, vases, &c., are made of serpentine. About one ton in four is of fine quality. Some- times beautiful blocks 7 feet long, and weighing three or four tons, have been obtained ; the blocks command ^5 to 10 per ton. The promontory of the Lizard is rich in this kind of stone. Sevres Porcelain. This manu- facture, like those of Berlin, Mu- nich, and Dresden, differs from anything in England, because it is supported at the Government ex- pense. With us, productive industry is left pretty much to itself, to fight its own battles in the market ; but on the Continent a more paternat or protective system is often adopted. At Sevres the factory is supported by national funds, and carried on as a school of design, without reference to profit or loss indeed, there is a regular annual loss. The texture of the porcelain made there is so ex- tremely light, delicate, and tender as to be unsuitable for ordinary do- mestic use ; hence the Sevres pro- ductions consist chiefly of vases, tazzas, slabs for picture-painting, and the like. Sewing- Machine. There are few inventions of recent date which have been brought into use more rapidly and extensively than the sewing machine. In England, where the labour of sempstresses is too often very insufficiently paid, it would have seemed absurd and even cruel to invent a machine which (accord- ing to popular notions) would tend to lower that payment to a still greater degree. Hence the sewing machine could hardly have esta- blished its position if it had been invented and brought out in Eng- land. In the United States, how- ever, where women's labour is not so abundant as in this country, the same difficulty does not present itsell The sewing machine was accepted as a real boon, and came into use to an almost inconceivable extent. Since then a wonderful lesson has been learnt in England ; sewing machines are coming more and more largely into use. every year, after the first prejudice against them was re- moved ; the better class of workers can earn more at the machine than by the needle, while the humbler workers do not earn less per week SEW 328 SHA on an average than before the ma- chines were invented. The patents for sewing machines are so nume- rous, and the inventions patented are often so complex, that the whole subject is an embarrassing one to most readers. Nevertheless, the working depends on a few simple principles. If we watch a needle- woman in the various processes called by her sewing, stitching, felling, hemming, running, tacking, basting, whipping, &c., we see dif- ferent modes of thrusting a threaded needle through the cloth, and of entangling the thread in its own loops on one or both sides of the cloth. The machines imitate more or less closely the movements by which all this is done some of them attempting only a few of the movements, some attempting all. The running stitch, the loop stitch, the chain stitch, the lock stitch are among many kinds of looping which have one by one been brought within the scope of the machine. The machines have sometimes been clas- sified into two groups the single- thread and the double-thread. An- other classification is into four groups those which send the needle com- pletely through the cloth; those which hook the thread into a chain- stitch by a sort of crochet-needle ; those which form a loop by a second thread carried across the first by a sort of shuttle ; and those which form a tightly-compacted chain-stitch of two threads. Some of the machines are worked by pedal or foot-lever, while others have a hand-turned wheel as a substitute. Many ma- chines to perform various kinds of tambour and embroidery-work were invented before any of the sewing machines usually so called, although they really employed mechanism to carry one or more needles through the cloth. The sewing machine, however, does not imitate those (see EMBROIDERY) in working many needles at once ; its efficacy consists mainly in the very rapid movements of one needle, or, for some kinds of stitch, two. From the time when Elias Howe patented his first sewing machine, in 1845, variations in the mode of produc- ing these movements have been the chief subjects of the patents. As to the rivalry between Howe, Thomas, Wilson, Wheeler, Newton, Singer, Grover, Baker, Wilcox, Gibbs, Werd, Wanzer, and other inventors, it has been productive of much benefit, each finding out something which had escaped the notice of his predecessors. There is no best sewing machine ; each has its own merits for particular kinds of service. It would be out of place here to describe the minute details and modes of action of the sewing machines ; so numerous and intri- cate are the needles, needle slides, feed motions, vibrating and other levers, cams and cam grooves, sup- ply wheels, driving pulleys, shuttles, bobbins, thumb screws, rocking levers, elastic springs, thread-lifters, slotted movable pieces, rotating loop-hooks, c. ; and every differ- ent machine has its own particular selection of these working parts. In some of the machines trimmings can be sewed at the rate of a yard a minute. Some are specially fitted for general outfitting and boot and shoe work. Some for finer work can make the enormous number of 3,000 stitches in a minute. Some will stitch the uppers to the soles of 150 pairs of boots or shoes in a day. Shagreen (see LEATHER) is made of shark, horse, ass, mule, or ox skin, and is dried without being tanned. Shale, an indurated clay, largely mixed with carbonaceous and other matters, is a great storehouse for many substances highly useful in the arts. (See ALUM; NAPHTHA; OIL; PARAFFINE.) Shamoy Leather, properly Cha- mois, was originally made from the SHA 329 SHE skin of the chamois goat, but now a similar process is employed with other skins. The best kind is from doe-skin; the cheapest kind from the flesh side of split sheep-skin, the grain side being tanned into skiver leather for hat-linings. If the whole skin is used, as in doe-skin, the grain is rubbed off with pumice-stone; the skins are steeped in bran- water; they are wrung out, slightly sprinkled with oil, and beaten with fulling stocks, having heavy wooden ham- mer heads coated with copper. This oiling and beating is repeated two or three times. After fermenting for a time in a warm room, the pelts are found to have thoroughly incorpo- rated the oil in their substance ; and a few finishing processes bring them to the state of soft, thin, pliable lea- ther. This is popularly known as wash-leather, as it is the only kind which will bear washing without losing whatever colour may have been given to it. Shaping Machine. This is one of those very useful machine tools which nowrender such a large amount of service in operating upon metal and wood. It is usually a kind of planing machine, in which the tool is attached to the end of a horizontal bar, to which a reciprocating motion for cutting is communicated in the direction of its length. The work is either fixed to a horizontal table, with longitudinal and vertical adjust- ments, or to an arbor. The machine is employed for shaping levers and cranks, or curved and plane forms in general ; it is susceptible of many varieties in construction and detail. In some of them the tool has a stroke of 12 inches, and the bed is 7 feet long. Shawl Manufacture. Under CASHMERE the beautiful shawls of the East are noticed. About 1784, owing to the large prices which Cashmere shawls brought in Eng- land, a Norwich manufacturer en- deavoured to produce saleable imita- tions of them. He so far succeeded as to suggest many experiments in combining Piedmont silk warp and fine worsted weft in the same shawl, the design being worked in by a pro- cess of darning by hand. It was not until 1805 that a Norwich shawl was produced entirely in the loom. Paisley next took up the manufacture, and succeeded in producing, with fine wool without silk, remarkably skilful imitations of the real Cash- mere shawl, at such low prices as to lead to the establishment of a considerable department in that town and vicinity. In 1802 Paris entered upon the manufacture ; and it was the enormous expense of setting up the loom for one of these shawl patterns that suggested to Jacquard the beautiful machine known by his name. The French imitations of the real Cashmere shawl are more per- fect and costly than those of Nor- wich or Paisley. Nevertheless, the Scotch manufacturers are making such rapid advances, that they are every year approachingnearer to their rivals. Besides great care in the dyeing, a Scotch shawl of the highest quality will employ a skilful weaver a month or more to make it ; and then the weaving represents more than half the selling price of the shawl. Notwithstanding the increase in the home manufacture, there are still 10,000 to 15,000 real Cashmere shawls imported annually, of an average value of about ^20 each. For the connecting-Jink between the shawl and the Scotch plaid see PLAID. Shearing 1 . In woollen-cloth ma- nufacture, after the fibres have been entangled into a kind of felt by full- ing, and raised into a kind of pile by teazling, they are cut into a beau- tifully smooth soft nap by shearing. This was formerly done by hand, men using large shears in a very dex- terous way ; but now an admirably- devised shearing machine is em- ployed. Here there is a flat, thin SHE 330 SHE wheel, having eight very sharp discs of steel attached to its surface close to its circumference. The wheel ro- tates ; the discs rotate on the wheel ; and there is thus a kind of planet motion combined with satellite motion. The cloth is spread flat on a table ; a half-ring plate is laid upon it, with the concave edge made very sharp, and the action is such that the fibres of the pile, caught between the keen edge of each disc and the keen edge of the plate (as between the blades of a pair of scissors), are cut or sheared. The discs pass many times over the surface, cutting oft' a minute portion of pile each time. Shearing machines of different con- struction are sometimes used for the back of the cloths. See further under WOOLLEN-CLOTH MANU- FACTURE. Shears are in action merely large scissors. (See SCISSOR MAKING.) Shear Steel. (See STEEL MA- NUFACTURE.) Sheathing:, for Ships. Among the numerous substances tried for protecting ships' bottoms from the attacks of marine animals, lead was for a long time used ; then copper; but now sheathing metal is made for the purpose, an alloy of copper and zinc. (See MUNTZ'S METAL.) For sheathingfelt, to cover steam-boilers, see FELT, FELTING. Sheers are a kind of lofty and powerful crane, used for hoisting masts, steam-boilers, and other heavy fittings into and out of ships. They consist of two or more long spars, resting on a quay or wharf, and meeting at the top, which top projects over the water. When a ship has been brought into position, the spars act as a crane through the medium of suitable pulleys, ropes, windlasses, &c. A much more powerful lifting apparatus is noticed under DERRICK. Sheet Glass. Manufacturers are quite at variance as to the name which should be given to this kind of glass. Sheet, cylinder, broad, spread, Ger- man all these designations are used. The mode of manufacture is as re- markable in its way as that of crown glass. The glass being ready jn the melting-pot (see GLASS MANU- FACTURE), the workman collects a quantity of it on the end of his blow- ing tube, rolls it on an iron slab, blows through the tube, re-heats the mass of glass, keeps the tube rotat- ing on its axis, and so continues un- til the glass extends as a sort of irre- gular bottle-shaped globe beyond the lower end of the tube. Then swinging the rod several times in a great vertical circle, the glass elon- gates into a sort of sugar-loaf, with the broad end attached to the tube. The apex of the sugar-loaf bursts open, and there is then produced an open cylinder, attached in a sur- prising way by its closed end to the tube. All this time the glass is in a glowing state ; and the alternate rolling, rotating, blowing, and swing- ! ing are continued until the substance assumes a solid consistency, although still quite hot. By the aid of a few tools the cylinder i* brought to a true shape while still somewhat soft ; by a touch with a wetted iron rod it is separated from the tube; by a line drawn with another wetted rod it is split open from end to end, ready to spread out as a flat quad- rangular sheet. The cylinder is transferred to the flatting furnace > with the slit uppermost ; the heal causes it to open, and a workman flattens it out with a wooden polishei moistened with water. However care- fully this process may be conducted, there is always a -waviness in the glass, which detracts from its other- wise useful qualities in glazing prints and drawings. It is only about a quarter of a century ago that this mode of making glass was imported from Germany into England, since which time Messrs. Chance and Messrs. Hartley have introduced many improvements, both in the SHE SHI working apparatus and in the mode of moulding. Sheet glass is espe- cially useful in glazing large struc- tures, such as exhibition buildings, railway stations, &c. Sheet Lead. This highly useful substance is made in two ways, by casting and by milling, the latter being the more modern and effec- live of the two. (i.) Cast Sheet. in the casting process, a strong table, possibly 20 feet long by 5 broad, is covered with fine river sand. Pigs of lead are melted in a caldron near at hand ; the lead is ladled into an oblong trough ; and the trough, suspended over the table, is tilted up. The lead, flow- ing over the sanded surface, is spread out smooth by means of a wooden stroker or staff, a raised edge around the table serving both to prevent the lead from running off, and to define the thickness of the sheet. (2.) Milled Sheet. In the milling or rolling process the lead is first cast into a slab 6 or 7 feet square by 6 inches thick. This is lifted by a crane upon a long frame 60 or 80 feet long by 8 wide, fur- nished with wooden rollers from end to end, about a foot apart. In the middle are two heavy cylinders or iron rollers, one over another, and 5 or 6 inches apart ; they are 16 inches in diameter, perfectly smooth, and capable of rotating in either direction. The slab of lead is rolled backwards and forwards between these cylinders, becoming thinner each time ; and the distance be- tween the cylinders is adjusted each time to suit this reduction of thick- ness. The lead stretches out in length, but not in breadth, as it becomes thinner, until any required thickness results. Sheet-lead is known by numbers, from 5 to 9, indi- cating the number of pounds in a square foot. Shell Lac, or Shellac. (See LAC.) So useful is this substance in making varnishes, polishes, ce- ments, &c., that 32,000 cwt. was imported in 1867. Shells. (See MOTHER-OF-PEARL and TORTOISESHELL for the two kinds of shell most used in the arts. For Shell Cameos see CAMEO.) Shells, Artillery, are cannon balls, or at least projectiles, filled with explosive substances. The theory of their action is, that the projectile will burst, either during its flight or when it strikes an ob- ject, and that the widely-scattering contents will work great destruc- tion among the enemy. The bomb or bomb-shell, fired from a wide- mouthed mortar, has a slow-burn- ing fuse attached to it, which kindles gunpowder within the shell in a certain number of seconds after leaving the mortar, and thus pro- duces the bursting : such shells are usually from 5 to 13 inches dia- meter. The Shrapnell shell is full of bullets ; it is timed to explode about 100 yards in front of the enemy, and then to carry a shower of bullets into them. The percus- sion shell explodes only at the instant when it strikes an object. The Armstrong shell is elaborately built up of definitely-shaped pieces of iron, closely packed together; it has a fuse timed to act at a particu- lar instant, and then the whole fabric bursts and scatters with terrific vio- lence. The Lancaster, the Whit- worth, the Boxer, the Palliser, and many other kinds of shell, are ex- pressly adapted to special forms of rifled guns. Occasionally monster shells have been made for monster mortars, as much as 36 inches in diameter. Ship Building. The building of a timber-ship may be regarded as a kind of carpentry on a very large scale. The following is a brief sketch of the order in which the successive processes take place. (i.) The Design and the Moulu. On the floor of a very large room SHI 332 SHI (the mould loft] the ship's draughts- man chalks a great number of lines, the lengths and curvatures of which relate to the sizes and shapes of the timbers to be used in the ship. Thin pieces of American deal, called moulds, are prepared by the guidance of the chalk-marks ; and these moulds guide the sawyers in cutting the great timbers. Nearly all the pieces of oak, elm, &c., for a ship's frame are cut by hand, the ever-varying sizes and curvatures rendering the work unsuitable for machines. (2.) The Keel. A. build- ing slip is prepared on a piece of ground sloping down to the water. Blocks of oak are placed in piles at regular distances along this slip ; and on these blocks the keel is built. The keel is made of elm, the separate logs strongly scarfed together. (3.) The Frame. The keel forms the backbone of a ship, of which the frame-timbers are the ribs, &c. The names and positions of these timbers vary greatly. The stem curves upwards from one end of the keel ; the stern-post stands nearly upright at the other end ; the floor-timbers jut out nearly at right angles from the keel; the dead-wood fills up vacancies between the keel and the end floor-timbers ; thefuttoc&s are the bulky pieces of timber of which each rib is built up, bolted together in the strongest pos- sible way ; the top-timbers form the summit of the futtocks, as the floor- timbers do the basis ; the keelson, stemson, and stemson are interior strengtheners of the keel, stem, and stern - post. (4.) The Planking. The frame-timbers of a ship are hidden by the planking or skin planks of oak from 3 to 6 inches thick. The planks are very accu- rately shaped, each for its proper place, then steamed to enable them to bend a little, and then bolted se- curely to the framework. The boring of the holes to receive the bolts is laborious work, as the oak timbers are both very hard anil very thick. The bolts are iron, copper, and oak, the last being called tree- nails or trenails. The narrow crevices between the planks are filled up with Oakum (which see). (5.) The Beams and the Decks. The beams, stretching from side to side, prevent the ship either from bulging out or from collapsing, while at the same time they serve as joists to support the decks. They are very stout and well-finished timbers, fastened to the frame-timbers by clamps and knees of wood and iron, and supported by pillars or columns underneath. The spaces between the beams are crossed and recrossed by smaller timbers called partners, coamings, carlings, &c., which help to give support to the decks. The decks, made of Baltic fir, vary from 2 to 4 inches in thickness, and the planks are driven as closely together as possible, to obviate breakage. (6.) Launching. At or about this stage of the building, the ship is usually launched. (See LAUNCH- ING.) (7.) Masts and Yards. The making of port-holes, magazines, bunkers, cabins, berths, luggage- rooms, hold, Sec., is a kind of car- penter's work, which goes on by degrees during the building of the ship. The masts are made by a distinct set of men. There are three masts for a large ship, two for a schooner or a brig, and one for a sloop or a cutter ; besides this, each mast is usually built up of two or more, called lower, top, and top-gallant. According to their position, begin- ning with the stern, the three masts are called fore, main, and mizzen. To aid towards the stability of the masts, and the attachment of sails and rigging to them, there are yards, booms, tops, cross - trees, trestle-trees, and timbers and spars of various kinds. A very large mast is built up of pieces called spindles, side-trees, cheeks, fillings, cant pieces, front fishes, and other SHI 333 SHI odd names, bound together by iron wedges driven in hot. Whatever names may be given to vessels, be they ship, frigate, brig, corvette, schooner, brigantine, cutter, ketch, or what not, the building depends on the same general rules, modified in detail according to the size and shape of the vessel. Various mat- ters relating to the finishing of a ship will be found briefly treated under BLOCK MACHINERY, MAST, RIGGING, SAIL CLOTH, SHEATH- ING, SHEERS, &c. Ship Building-, Iron. If steam- vessels had never been built, iron ships would probably have been little known ; for timber still continues to be preferred for sailing ships. When, however, the great engineering firms on the Clyde began to make engines for steamers, they easily saw that almost the same class of workmen could make iron ships ; and that in a neighbourhood where iron is cheap, it would be well worth while to culti- vate iron ship-building as a branch of trade. The Mersey, the Thames, the Avon, the Tyne, and the Wear took the matter up; and now the building of iron steamers is a very important branch of industry. There is much more simplicity in the build- ing of an iron ship than one of tim- ber. The rivet is the great bond of union. Bar-iron, angle-iron, sheet- iron, plate-iron, brought into form by rolling, cutting, drilling, punch- ing, slotting, and other processes, are connected together by thousands of rivets. Angle-iron represents the frame-timbers, and sheet or plate iron represents the planking. Some of the thicker masses in particular places are of cast-iron, but generally speaking the iron is in the rolled state. In the mightiest ship ever built, the Great Eastern, which is essentially an iron ship, there is just the same riveting of plates and sheets to bars and angles as in a smaller vessel ; the difference is in the scale of operations. Ship Raising:. The raising of sunken ships is becoming an art in which much ingenuity is displayed ; and many successful achievements have rewarded the exertions of the inventors. Sometimes it is worth while to recover a ship for the value of the hull or its contents ; sometimes merely to remove her from a spot where she would obstruct the pas- sage of a channel. A remarkable and successful mode of ship-raising was adopted in Belfast Lough in October, 1868. An iron-built mail steamer, the Wolf, had been sunk by a collision, in 42 feet depth of water ; and Messrs. Harland and Wolfi" undertook to raise it. As she hadsunk 8 feet into the mud, it was not practicable to pass lifting chains under the hull ; and therefore other means had to be adopted. A float- ing raft of iron air-tanks was made. The tanks were of sufficient capacity to have a flotation power of 852 tons. They were arranged in two pairs, and formed into two distinct rafts, by stout double cross logs. On the cross logs were fixed the lifting screws, with platforms for the work- men to stand upon. From these two rafts were suspended fifty stout chains, each capable of lifting 25 tons ; their lower ends were hooked into fifty side-light holes in the hull of the sunken vessel, over which the two rafts were moored. These pre- parations required many months to complete; for it was necessary to employ divers in all explorations of the sunken ship. All being ready, abundant hands were obtained to work the screws or windlasses ; the chains were made taut; they gripped well hold of the sunken ship ; and after six hours' vigorous work the ship was lifted fairly out of the mud, and hung suspended from the rafts in the sea. About 250 men con- tinued to work the fifty screws which lifted the fifty chains, until at length the Wolf was raised to the surface, and tugged on to Belfast. Among SHO 334 SHO many other modes, more or less suc- cessful, of raising sunken ships, may be mentioned that adopted by Mr. Magnay, at Melbourne. A cylinder made of plate or sheet iron is half filled with water, to which a certain amount of zinc and sulphuric acid is added. The cylinder is lowered to the sunken vessel. There are also lowered two large pieces of canvas, Avhich, by the aid of ropes, chains, and angle-irons, may be fixed to the ship, and at the same time allowed to expand somewhat in balloon form. All being ready, a diver de- scends, sets in action an iron bar which passes into the cylinder, and breaks the glass carboy containing the sulphuiic acid. The acid acts upon the zinc and water, and gene- rates hydrogen, which passes through india-rubber tubes into the hollow canvas receptacles. The gas, being only one-fourteenth as heavy as atmospheric air, rises by its great buoyancy, and lifts the ship with it. A heavy barge, purposely sunk for trial, has been raised from the bot- tom of a harbour by this singular method. Shoddy. This odd name, and the equally odd name mungo, are given in Yorkshire to old wool, so worked up as to be again available in the manufacture of woollen goods. The fibres, once having passed through the various manufacturing processes, are not capable again of felting into strongcloth ; but they become suitable for inferior goods when mixed with new wool. Shoddy is obtained from worn-out woollen garments,blankets, carpets, flannel, and worsted stock- ings ; while mungo is obtained from new or unused tailors' cuttings. These odds and ends, mostly full of dust and dirt, are sifted and cleaned in rotat- ing machines, sorted into kinds and colours, cut up into bits to separate knots and seams and selvages, torn up into shreds by rapidly-revolving cylinders studded with spikes, mixed with new wool, and subjected to the usual spinning and weaving opera- tions. There may be ten times as much new wool as old, or ten times as much old as new, or any inter- mediate ratio ; and hence the variety of goods produced is considerable. They are mostly employed in making great-coatings, and coarse and cheap clothing generally : pilots, a cloth for heavy pilot coats and jackets, use up an immense quantity of shoddy. Good mungo is often stronger than inferior new wool; and therefore these mixed cloths are sometimes both good and cheap. It was estimated in 1860 that 40,000,000 Ibs. of shoddy and mungo were in that year used in Yorkshire; while in 1867 the total con- sumption was as high as 80,000,000 Ibs., of which 20,000,000 Ibs. came from abroad. Shot, Artillery. Cannon balls, solid spheres of iron for smoothbores, have nothing special about them ; but the shot for rifled ordnance are much more carefully shaped, bearing some resemblance in this respect to the formidable missiles described under SHELLS, ARTILLERY. Shot Manufacture. The mak- ing of ordinary lead shot is conducted in rather a curious way. It used to be effected by rolling little cubes of lead between two stones, or shaking them up together in a bag; but it now consists in solidifying drops of molten lead, much as rain-drops solidify naturally into hail. A shaft is formed either a built-up tower, or (as at Newcastle) a de- serted coal-pit. Lead is melted with a little arsenic, which improves the quality of the shot. A kind of colander is provided, an iron vessel with holes in the bottom ; and these holes are temporarily covered with a layer of lead scum or dross, to act as a filter or sieve. A workman takes a ladleful of melted lead, and pours it into the colander, which is sup- ported on a tripod over a hole in the floor opening to the shaft or pit beneath. The lead descends, through SHR 335 SIG the holes in the colander, as a silvery rain of drops ; and the drops fall into a tank of water at the bottom. If the quality of the lead be well chosen, the quantity of arsenic pro- portionate to the size of shot, the holes in the colander properly con- verted into a filter or sieve, and the height of the shaft well determined, the shot will become perfect little spheres by the time they reach the bottom. The shot, when so far made, are taken up from the water- tank, dried on steam-heated iron plates, sifted into sizes through other colanders or sieves, deprived of mis- shapen specimens, and rolled in a barrel containing black-lead. Lead shot usually vary from -$ to --^ inch in diameter. The elongated shot or bullets now used for rifles are made at Woolwich in a rapid and beautiful way. The machine for this purpose consists of four sets of dupli- cate punches and dies, independently worked in pairs by two eccentrics, driven by gearing from two separate driving shafts. The lead, coiled round four reels, is fed from them through a shearing lever into the grippers, where it is clutched; a piece is cut to a suitable length by an upward movement of the shear- ing lever ; the grippers then open, the piece cut off falls down, and is clutched by another piece of appa- ratus. At this moment a punch advances, and presses the lead into the die, thus forming a bullet. A small plate comes up immediately in front of the die, and the bullet is pushed through it by a small pin, worked by a lever and cam : by this operation the ragged edge is removed which had been left on the bullet by the die. The machinery, when driven at the rate of thirty revolutions per minute, will make 120 bullets in that time, or 72,000 in a day of ten hours. Shrapnell Shell. (See SHELLS, ARTILLERY.) Shuttle is a small boat-like in- strument, which contains the weft thread necessary for weaving. It is a kind of cylinder, tapering at both ends, having a cavity at the top, and sometimes two wooden wheels to run upon. In the cavity is placed the cop, a sort of bobbin on which the weft is wound. When the shut- tie is travelling along in the act of weaving, the cop unwinds, and the thread comes out through a small hole in the side of the shuttle. In the simplest weaving the shuttle is thrown to and fro by hand. In a better kind of work the shuttle is struck by two pieces of wood called peckers, so placed that, with the right hand, the weaver can strike the shuttle from left to right or from right to left, thereby saving time. The shuttle runs along a groove, called the shuttle-race, in the lower bar of the batten frame. See further under LOOM, HAND and M ACH i NE ; WEAVING. Sieves ; Sifters. The sieves or sifters used in various branches of manufacture are made of horsehair, gauze, silk, wire, perforated parch- ment, and perforated sheet-metal, according to the kind and fineness of the substance to be sifted. Some sifters have a jigging or jerking mo- tion imparted to them by machinery. Signals. Signals by sound, from ships to the shore, &c., may be made by cannon, bells, tide-bells, fog-bells, explosives laid on railways, &c. Sig- nals by sight are more usual and use- ful, comprising lanterns, torches, coloured flags, discs of different colours, arms or levers at different angles, flashing intermittent lights, &c. The signals for the mercantile marine are very remarkable. By the provisions of an Act passed in 1854, every British ship must have a num- ' ber. There are now upwards of 40,000 such ships, and a numeral is specially retained for each. Books and tables are kept, in which the ownership, tonnage, &c., of every ship are noted down. When two ships meet at sea, each can identify SIL 336 SIL the other by means of the number belonging to it. For instance, it may be that No. 25,413 is the Isabella, 540 tons, of Liverpool ; and no person is allowed to give another number to that particular vessel, or that particular number to any other vessel. But how is the number of a ship to be shown at sea? This is done by means of flags. Eighteen flags are provided, differing in co- lour, size, shape, or device. Every flag represents a letter; and every letter is entered in a code book or book of signals. By hoisting one, two, three, or four flags at a time, 80,000 different combinations may be made among a choice of eighteen flags. All the combina- tions of four at a time, amounting to 70,000, are reserved for ships' names ; so that there is a reserve for some years to come fornewships. One flag only denotes such useful little words as "Yes," "No," &c. Two flags denote various nautical phrases and expressions useful on shipboard. Three flags (of which there are several thousand combinations), de- note short conversational sentences, questions, and answers, in great variety. Thus it is that by ringing the changes among eighteen flags, two ships can speak to each other at sea. For special kinds of signals see DRUMMOND LIGHT, LIGHT- HOUSE ILLUMINATION, TELE- GRAPH, &c. Silica; Silex. Under FLINT, QUARTZ, SAND, and many other headings, mention is made of the important substance to which these bodies owe their chief properties. The true base, silicum, is a metal sometimes called silica, known only to scientific chemists. It puts on the external form of a dark brown powder, a dense dark solid, or an hexagonal crystal, according to the mode in which it is obtained from flinty minerals. The principal oxide is silica or silicic acid, obtained from fluor-spar by a particular treat- ment with sulphuric acid. This silica is one of the most abundant elements in the rocks of which the crust of the earth is formed. Rock crystal, quartz, agate, flint, chalce- dony, opal, felspar, sandstone, sand all consist either wholly or princi- pally of silica. Chiefly in the form of sand or of flint, it plays a most important part in the manufacture of glass, enamel, porcelain, pottery, mortar, cement, and numerous other substances of every-day use. Silk is perhaps the most beautiful of all the fibres employed for textile purposes, owing to its glossiness, its softness, its capability of taking rich dyes, and the embroidering for which it is suited. Silk is a kind of gum exuded by the silkworm ; and great care is needed to rear these little creatures, so as to obtain silk of good quality and in large quantity. China, so far as we know, was the oldest silk-rearing country ; thence the art travelled to India, Persia, and Egypt, and in much more recent times to Greece, Italy, and France. Mulberry leaves being the favourite food of the silkworm, a silk-rearing country requires a good crop of those leaves. A large trade has recently sprung up in the ex- portation of silkworms' eggs from India to Italy. Silk Culture. The order of processes in the culture or rearing of silk is simply as follows : (i.) The insect (the Bombyx mori] deposits eggs, smaller than grains of mustard seed. (2.) Each egg hatches into a caterpillar about inch long, acquiring a new skin as often as the old one becomes too small ; four of these moults or re- newals take place, at the end of which time the insect is 3 inches long. (3.) The full-grown cater- pillar, ceasing to eat, begins to ex- pel the silk from two small orifices in the head. (4.) The silk, at first a glutinous gum, hardens into a thread or fibre, which the insect winds SIL 337 SIL into a ball called a cocoon. (5.) The body of the caterpillar gradually lessens in bulk, while the cocoon be- comes larger and larger. (6.) The silk-producing being finished, the caterpillar changes into a chrysalis, a kind of lumpy, inanimate worm. (7.) In two or three weeks the chry- salis changes into a winged moth, and escapes from its prison within the cocoon. (8.) Anew generation of eggs is provided for, and then the creature dies. Many other kinds of caterpillar yield species of silk in a similar way, but none so good or so plentiful as the silkworm. The silk -rearer has to begin with the be- ginning the eggs. These are so kept at a low temperature as not to be developed to maturity until the mulberry leaves are ready. In some regions oak leaves are used as food for the caterpillar ; but there is no really effective substitute for the mul- berry. All attempts at profitable rearing of silk in England, for pur- poses of trade, have hitherto failed, on account of the c'dmate. So much extraneous matter has to be removed in various ways, that zoo Ibs. of ordinary cocoon yield only 8 Ibs. of reeled silk. The Chinese silk, which is the best, is obtained from larger cocoons than that of India. Silk Filature. This name is some- times given to the processes which intervene between the silkworm nursery and the export market. They are somewhat as follow : (i.) The worm within the cocoon is killed by heat, without giving it time to de- velop into a winged insect. (2.) The floss silk is removed from the exterior of the cocoon. (3.) Placed in hot water, the gum of the cocoon becomes softened, and ends of the fine silken filaments are loosened. (4.) These ends, by means of a rotary reeling- frame, are wound into a con- tinuous length. (5.) The silk, re- moved from the reel, is made up into hanks and bundles, which differ greatly in size and form in different countries; the silk, too, is in some instances nearly white, in others of a golden yellow. Small as it is, the filament of silk is much stronger than one of flax or hemp. The commodity, under the designation raw silk, is then ready for the mar- ket. By the careful crossing of breeds, the silk now reared in Europe is much better in quality than used formerly to be the case. Nevertheless there are diseases af- fecting the silkworm which are as yet little understood, and which sometimes render the crop very defi- cient. There are many technical classifications and groupings of silk. Besides the original Bombyx mori, there are the species Cynthia, My- litta, Atlas, and Selene all more or less cultivated for the sake of the silk. The dealers in cocoons place them in nine groups good, calcined, co- colous, choquettes, dupions, souf- Jlons, pointed, perforated, and bad all marked by characteristics which affect their value in the market. The length of filament in each cocoon is usually about 300 yards, and in some instances much more. In round numbers, it may be said that 250 cocoons weigh I lb., 12 Ibs. of co- coons yield I lb. of silk ; and there- fore 3,000 cocoons are needed for a pound of silk filament. Silk Manufacture. In early times, and in Oriental countries at the present day, the manufacture of silk into fabrics has been almost wholly done by hand, in a slow and often very inefficient way. Water- wheels to move such machines as were necessary were first used in England about a century and a half ago. About the commencement of the reign of Victoria it was still be- lieved that silk for the best goods could not be spun and woven by steam power ; . but one improvement after another has enabled the ma- chinist to triumph over all difficul- ties, until at length the silk-mills of Manchester, Coventry, and other z SIL 338 STL towns exhibit a wonderful conquest over the delicate little filament by the mighty steam-engine. The chief processes whereby raw silk is brought to the woven state are the following: (i.) Winding. Thesilk is disengaged from the hanks in which it is imported, and wound on hexagonal frames called swifts, from which it is transferred to bob- bins. Different qualities of silk require different details of treat- ment ; but the main treatment is the same for all. (2.) Clearing. To remove the little irregularities on the surface, each thread of silk is made to pass under the action of a kind of scraper of steel, or else be- tween two steel rollers. This is done in the clearing -machine, which transfers the clean fibre to other bobbins. (3.) Spinning. There then comes into use the spinning machine, which has a number of spindles placed upright, and me- chanism to make them rotate with great speed. The bobbins on the clearing machine are placed in a row ; each filament of silk is twisted to give increased strength, and other bobbins receive the twisted fila- ments. (4.) Doubling. The com- bining of filaments now begins. Two 01 more are twisted round each other in the doubling machine into a little cord or thread, hard or soft according to its purpose, but equable in tension in every part. Here, as in the other machines, the silk is transferred from one set of bobbins to another. (5.) Throwing. A fur- ther twisting and combining here takes place in the throwing ma- chine, which acts nearly in the same way as the machine just noticed. For some purposes the spinning and the throwing are combined in one operation ; and for some others a throstle frame is used. (6.) Gloss- ing. The silk is usually dyed after the throwing, and is then transferred to the glossing machine, where the combined action of moist steam and stretching at once elongates the silken thread and gives it a gloss. Silk can be stretched in length one-tenth, a change which cannot safely be attempted with flax, cotton, or wool. (7.) Winding. The silk, having thus gone through all the processes of spinning and dyeing, is once more wound on bobbins, ready to be used as warp or weft, as the case may be. The silken thread, simply wound and cleaned, is called dumb singles; when wound, cleaned, and thrown, thrown singles ; if single twisted, tram; if double twisted, organzine; if the natural gum is left in it, hard silk ; if the gum has been removed, soft silk; floss silk is the outer portion of the cocoon, worked up into yarns for cheap handkerchiefs and shawls by processes somewhat resembling cotton-spinning ; sewings is a name that explains itself. The quality of silk is denoted by the number of yards which go to a denier, equal to 24 grains, and equal also to - 2 l 4 -th of an ounce. For the weaving processes it will suffice to refer to JACQUARD MACHINE ; LOOM, HAND and MACHINE ; WEAVING, &c. The more impor- tant silk goods, such as velvet, satin, crape, ribbons, brocade, &c., are noticed under their several headings. Mr. Cola gives an esti- mate for a silk-mill of moderate size, containing all the appliances for spinning and weaving, from the imported hanks of silk to the finished gros Naples or other goods. There is the requisite supply of winding, clearing, spin- ning, doubling, throwing, stretching, glossing, and warping mills, &c., to feed 2,000 spindles, 100 looms, and loojacquard machines; ^"2,600 in all, with ^1,500 more for steam- engine, boilers, and mill gearing. According to a recent estimate there were 770 silk-mills in the United Kingdom, provided with 1,300,000 spindles, and n,ooo SIL 339 SIL power-looms, and giving employ- ment to 51,000 operatives. What quantity of silk goods was produced by this manufacturing agency there is no reliable account ; but we know that in 1867 we imported 6,000,000 Ibs. of raw silk, and 2,000,000 Ibs. of waste and knubs. Much more silk is worn than is woven here; for we imported 3,000,000 Ibs. of foreign silk goods in that year, mostly from France. On the other hand, certain foreign countries take from us something of that which we buy, and something of our home make ; for we exported silk and silk manufactures to the value of ,1,000,000. Silver, next to gold, has at all times been the most valued among metals for purposes of ornament. It is very white, takes a brilliant polish, reflects light and heat abun- dantly, and is very ductile and malleable ; it melts at about 1870? Fahr., is harder than gold, and softer than copper ; it resists air and mois- ture well, but is soon tarnished with chemicals, and dissolves in many kinds of acid. These various pro- perties give it a considerable range of useful application in the arts. Many of the compounds of silver are highly valuable. Nitrate of silver forms the lunar caustic of surgeons, and is used in hair dyes, and in indelible ink. The sulphate is employed occasionally in separat- ing small portions of gold from large portions of silver. The chlo- ride, sometimes called horn silver, is of immense importance in photo- graphy ; and so, indeed, are the iodide and the bromide. With ammonia it forms fulminating silver, a very explosive compound. Silver is found in many parts of the world, in various degrees of com- bination with other substances. It is sometimes found pure ; wit- ness the magnificent specimen in the Copenhagen Museum, weighing 500 Ibs., brought from Norway. An ore called native amalgam, consist- ing of silver and mercury in minute flakes, is sometimes met with. Sulphide of silver, a greyish sub- stance, very fusible and rich in silver, is found in Saxony, Bohemia, Hun- gary, Mexico, and other countries. The chloride, of which theie are considerable quantities in Chili, shares with the sulphide in being the chief sources whence the metal is obtained by metallurgic pro- cesses. The bromide is one among many silver ores found in Mexico. Silvering 1 . Silver can be ap- plied to the surfaces of wood, paper, metal, and other substances, by nearly the same processes as those described under GILDING, except that, to silver brass, the composi- tion applied consists of chloride of silver, chalk, and pearlash, instead of silver and mercury. Silvering Mirrors. The ordi- nary looking-glasses with which we are all familiar are coated on the back with a highly-reflective white metal, which, though called silver, is really an amalgam of mercury, or quicksilver, and tinfoil. The pro- cess is a very remarkable one. A large sheet of tinfoil is unrolled and spread out flat on a very smooth and level table of slate or of iron. It is floated all over with mercury, poured out from iron bottles. . The sheet of plate glass, cleaned as perfectly as possible, is dexterously slidden along in a horizontal position upon the foil, in such a way that the foremost edge of the glass may push most of the mercury along before it, yet leave some mercury between the foil and the glass in every part, while all air is driven out. This done, the glass is loaded with heavy iron weights in every part a thing which could not be ventured upon unless both glass and table were perfectly flat and smooth. The heavy pressure squeezes out the superfluous mercury from between [ the glass and the foil ; and one end SIL 34 SIL of the table being propped up to a certain angle, the superfluity slowly drains off. By this time the thin film of mercury has become a solid amalgam with the foil, and gives a brilliant reflecting surface as seen through the glass. This process is still generally adapted for large looking-glasses ; but there are other methods by which a film of real silver is deposited on the back of the glass. In Drayton's method is used a silvering fluid made of nitrate of silver, ammonia, and alcholic solution of oil of cassia. A thin layer of this fluid is poured upon the clean surface of the glass, and upon this is applied a reducing fluid made of alcohol and oil of cloves; the one fluid causes the silver to separate from the other, and to deposit itself as an exceed- ingly thin film of brilliant metallic silver, which adheres to the glass. In VohVs method, adapted for the interior of glass globes and balls, gun cotton is dissolved in hot caustic potash ; and this solution is made to act upon nitrate of silver and am- monia in such a way as to precipi- tate the silver in a thin film. In SteinheiVs method the agents used are nitrate of silver, caustic ammonia, caustic soda, milk, sugar, and water; and the mutual action of these sub- stances is so brought about as to tie- posit a thin film of pure silver. In Thomson's method, used mostly to silver the interior of globes and bottles ; in Foucaulfs, for silvering convex and concave mirrors in sub- stitution of metallic specula for telescope"} ; in Martin's method ; in Petit Jean's method in all of these some oxide or salt of silver is the primary agent, so acted upon by Other chemical agents as to deposit a thin brilliant film of metallic silver on the glass. Silver Lead. A very beautiful proress has been devised by Mr. Pattinson, of Newcastle, for extract- ing the silver which nearly allsmelted lead contains. It depends on the fact that melted lead will become solid or crystalline sooner than melted silver. The vessels used are hemi- spherical cast-iron pots, each con- taining about 3 tons of metal, and heated by a fire underneath ; there are ten or twelve of them placed in a row. Pigs of lead being put in one of the pots, and the fire lighted, the lead melts, and a dross comes to the surface ; this is removed, and the fire is put out. As the metal cools, it is kept stirred, and crystals of lead gradually form ; these are removed by a large perforated ladle, and trans- ferred to the next vessel. This trans- fer goes on from one vessel to another, the lead losing portion after portion of its silver by successive processes of crystallising ; until at length all the silver is collected in what is called the rich pot, as part of a very rich silver- lead ; while the poor or de-silvered lead is collected in the market pot, from which it is poured into moulds, and becomes the lead of ordinary com- merce. In one variety of the process a little zinc is introduced to facilitate the separation of the silver from the lead. The lead is then cupelled, to extract the silver with which it has been enriched by the last process. The refinery or cupel furnace con- tains a cupel in the middle. This is an iron frame supporting a kind of large oval dish made of moistened bone-ash and pearlash. The lead, melted in a separate iron pot, is allowed to flow into the cupel when the latter is at a cherry-red heat. A dross soon forms, and then an oxide, which is blown off the surface by the action of a blast. As the lead wastes away by this, more is added, until the cupel contains 5 tons. After a time the weight is reduced to 2 or 3 tons, but all the silver remains in it. The charge is removed ; another charge is treated in a similar way ; and so on, until there is collected a quantity of rich lead containing 3,000 to 5,000 ozs. of silver. Again treated in a SIL 341 SIL furnace, this rich lead gives up its silver, which is obtained as a thick plate. All the dross and oxide are made to yield up their metallic lead again by treatment in a separate process. So successful is this refin- ingprocess, that it becomes profitable even when the lead contains only 3 ozs. of silver to the ton, and possibly even with | oz. If the lead contains antimony, tin, or copper, it is exposed to the action of air in a separate fur- nace before the refining, in order that these metals may be separated and removed in the form of oxides. If the pig-lead produced by smelting contains 10 ozs. of silver to the ton, it is enriched to 300 ozs. to the ton by the Pattinson process ; and these 3OOOZS. are extracted by the cupelling or refining process, leaving the lead really better for ordinary purposes than it was before. According to the Mining Records^ 700,000 or 800,000 ozs. of silver are raised annually in the United Kingdom. Most of this is obtained by de-silver- ing lead. Silver Mining. Silver does not seem to occur to any great extent as small particles in river sand and mud, like gold ; and therefore there is nothing exactly analogous to the "washing carried on with the more valuable metal. The actual mining processes are not peculiar, so far as they relate to digging the ore and sending it up to the surface {see MINING) ; but the depth of some of the mines gives a peculiarity to the mechanical arrangements. It is not by smelting that the silver is ex- tracted from the ore, but mainly by amalgamation, a process that de- pends on the powerful affinity be- tween silver and mercury. The sulphide found in Saxony, one of the chief European sources, con- tains only about 80 ozs. of silver in a ton of ore, a quantity so small that it would be dissipated altogether in any smelting process ; the other constituents are oxides and sul- phides of various kinds. The ore is spread out on a floor, sprinkled with a certain proportion of sea- salt, well mixed, and separated into heaps of about 4 cwt. each. Each heap is roasted in an oven, at a heat that grows higher and higher, and gives off various metallic and oxide vapours one after another, aided by frequent stirring ; it is finally drawn from the oven as a deep brown mass. This mass is ground fine between heavy millstones, sifted, bolted, and dressed. Then begins the amalgamation. The powder, with a certain quantity ot water and of wrought-iron in small pieces, is put into a barrel which rotates twenty times a minute; after this has gone on for two hours, mercury is added, and the whole rotated from twenty to twenty-five times a minute for sixteen hours. A liquid amalgam formed by this pro- cess, sepai-ated from certain slimy matters which collect on the sur- face as a scum, is drawn from the barrel into a trough, and thence through an iron tube into a receiver. Nearly all the silver originally con- tained in the ore is now in this liquid amalgam. Every 20 tons of ore have taken up about 60 Ibs. of iron and 1 1 Ibs. of mercury. The amalgam having been made, the next thing is to drive off the mer- cury from it. By filtering through close canvas bags, some of the liquid mercury is separated from the amalgam, which now forms a paste. This paste is put into a distillatory furnace, which is a pe- culiar apparatus, specially adapted to preserve and restore the two valuable metals, silver and mercury. The mercury, influenced by the heat, rises as a vapour, sublimes around a vaulted chamber, and falls as metallic drops into basins of water. The mercury thus re- covered is ready to be used again for other similar operations ; while the non-volatile parts of the paste, SIL 34 2 SLA containing silver with a great many other metals, remain in the fur- nace. By further processes of re- lining the silver is separated from the other metals, and brought to a pure state. Great care is taken, by subsidiary processes, to recover what little residue there may be of silver and mercury in the liquid, scum, sediment, paste, alloy, &c., in order that nothing may be wasted. Much activity now prevails in the silver mines of the United States. Silver was discovered in the Nevada ter- ritory in 1859, and the mining has gradually increased in amount and value ever since 50,000 dollars' worth in 1859, and thence rising to 17,000,000 dollars in 1866, giving a total of 70,000,000 dollars ( ^14,000,000; in eight years. Nearly the whole of this has been obtained from if miles of one par- ticular lode ; this lode is known to to be 55 feet thick, and the ore ob- tained from it yields & $s. of silver to the ton. Silver Plate, like gold plate, is made by the processes described under PLATING. Silver Substitutes. Many varie- ties of imitative silver are noticed under WHITE METAL. Siphon is a useful instrument for regulating the transfer of liquids from one receptacle to another. It is simply a bent tube, with one leg longer than the other. When the short leg dips into a vessel of water, and the long leg hangs outside, the water will rise to the bend of the tube, and flow off through the longer leg, provided the tube be first ex- hausted of air. This exhaustion may be effected either by suction with the mouth, by an air-pump, or by filling the siphon with water while inverted. Size is a kind of weak glue. (See GLUR MANUFACTURE.) Skates. The manufacture of these articles, which depends for its brisk- ness on frosty weather, requires great attention to the quality and shape of the metal, wood, and leather em- ployed ; in other respects it needs no particular description. Skins. (See FUR, FURRIERY; LEATHER; PELTS, PELTRY, &c.) Slag. (See IRON, &c.) Slate ; Slate Quarrying. Slate is one of those peculiar lands of stone which exhibit a lamellar or stratified structure. There are many varieties, several of which are useful in the arts. Among these are mica slate, used sometimes for paving and for lining furnaces ; talc slate, suitable for hones and scythe sharpeners; drawing slate, for crayon-drawing ; whetstone slate, another variety use- ful for hones ; slate clay, an ingre- dient in fire-bricks. But the most im- portant is roofing slate, forming the main substance of whole ranges of hills in North Wales, Devon, Corn- wall, and the north of England. The most celebrated in this country are the Penrhyn Slate Quarries, a few miles south of Bangor, at Llan- degai. A whole mountain is being quarried away by gradual ten-aces from bottom to top. The terraces are formed by the natural cleavage planes of the slate, and greatly assist the workmen by giving them ledges to stand on. The repeated blasts, by large masses of powder, produce a sound which reverberates remark- ably around the amphitheatre formed by the workings. Nearly two thou- sand men are dotted about the place ; and the whole scene witnessed from below is very impressive. The blocks of slate are mostly loosened from their rocky bed by blasting. These blocks are, by the lamellar structure above adverted to, easily split into slabs or sheets ; wide thin chisels, struck with a mallet, easily effect this ; and still finer chisels further slit the slabs into layers hardly thicker than leaves. Large slabs for billiard tables and other purposes can only be obtained out of exceptionably large blocks. Cross grooves cut on SLA 343 SLI the surface separate the slabs into smaller pieces. Slate Working-. All the arrange- ments for working up slate into use- ful and ornamental forms are made dependent on the peculiarly flat and thin structure of this kind of stone. The blocks are split soon after being quarried, else they lose their pro- perty of easy separation. Those in- tended for roofing are split to the required thickness, and made quad- rangular, being left to the slater for further treatment. In making bil- liard-table tops, chimney-pieces, and other large slabs of smooth slate, the slates, after being split into slabs of the proper thickness, are cut to the right length and breadth by circular saws revolving rather slowly. The surfaces are smoothed by planing machines, gradually worked from end to end, and from side to side. Mouldings and bead- ings are made by planing tools specially shaped. A finished slate surface is sometimes made to imitate granite or coloured marble by being rubbed smooth, japanned with vari- ous colours and devices, baked to harden the japan, smoothed with pumice-stone, and polished with rotten-stone. Slate is not well suited for turning or for carving, owing to its liability to chip in one particular direction. Some soft kinds, how- ever, are turned to make slate pen- cils ; other pencils are cut into shape, or are sometimes made of damped slate-powder pressed into form. Slating. When the slater ob- tains his supply of slates, they are in various sizes, which receive desig- nations of a peculiarly feminine and aristocratic nature, thus : Imperials, length varied, width 24 in. Duchesses ,, 24 in. ,, 12 ,, Countesses 20 ,, ,, 10 ,, Ladies 15 ,, 3 ,, There are also Westmorelands and Welsh rags, measuring sometimes as much as 3 feet by 2 ; and smaller kinds known as Delabole and Tavi- stock. The roofing slates used in London are mostly from the Bangor quarries. The slater cuts the four edges of each slate square and true by means of a tool called a sax, an iron knife about 16 inches long by 2 broad, with a wooden handle at one end, and a sharp point at the back of the other. The slate is rested on a block of wood, and by a few dexterous strokes each edge is chopped straight and smooth, while the point of the tool makes two holes near one end. The two surfaces of the slate are called the back and bed, and the two ends the head and tail. In slating, large slates are laid on battens, while those of smaller size are laid on continuous boarding. The successive rows of slating are fixed on the battens upwards to- wards the ridge of the roof, each one over-lapping the row below it, and breaking joint ; the exposed sur- face of each slate is the margin, the portion hidden by the overlapping is the lap; this lap is usually from 2 to 3 1 inches. The uppermost rows are finished by a ridge-strip of sheet- lead. The nails, of copper, zinc, or tinned iron, are so driven in as not to strain or bend the slate. In patent slating no boarding is used ; wide slates are screwed from rafter to raf- ter, and the joints covered by narrow slates bedded in putty, and also screwed. The chief object of pater.t slating is to adapt it to a roof of so small a gradient as 10, the usual average being not less than 25. Sleepers are timbers of moderate scantling, placed either on the top of brick walls, or under the rails of a railway, crosswise. Slide Best is an appendage to the turning lathe, to enable the work- man to advance from end to end of a long piece of work, such as a pil- lar or cylinder. Not only so : it enables him to perform work, such as the turning of metals, which would otherwise over-fatigue his SLI 344 SMA muscles. The slide-rest is attached to the lathe, but in such a way as to have a right-and-left motion. The cutting 'tool is held in a sort of vice ; the vice moves by means of a slide which the workman governs by a screw -handle. His part of the work consists, not in working the tool, but in regulating the movement of the slide and the vice. Another screw- handle regulates the depth of the cut to be made by the tool; one screw enabling him to work along the piece of metal, and the other across or around it. By a further adjustment the apparatus is made self-acting. A very beautiful ma- chine, Whitworth's duplex lathe, not only has this automatic action, but has a pair of slides and tools, so as to wor.c with double rapidity ; this is used for turning long metal shafts. This accomplished machinist has even advanced so far as a double duplex, 'with four rests and cutters at once, for turning large wheels. A slide-rest is always so constructed as to be shifted easily nearer to or fur- ther from the work, so as to adapt itself to different diameters. By one adjustment a cone may be turned, either solid or hollow, instead of a cylindrical surface ; and a graduation of the slide into inches and fractions of an inch enables the workman to insure great accuracy. A peculiar kind of slide-rest is employed in rose-engine turning, to produce those wavy curved lines so charac- teristic of that style of adornment as seen in watch-cases, for insta/ice. (See further under LATHE; SCREW CUTTING; TURNING.) Sliding* Rule is a mechanical aid to calculation. It consists of three slips of wood connected by pieces of brass. The slips are covered with engraved lines and marks of various kinds, denoting numbers, inches, rhumbs, angles, sines, tangents, logarithms, &c. ; and by certain slid- ing movements of these slips, cal- culations can be made. Slip. Two different meanings of this term are noticed under POT- TERY and SHIP BUILDING. Slotting Machine. (See MA- CHINE TOOLS; WOOD-WORKING MACHINE.) Slow Match, is a slower-burning composition than quick match. It is now mostly superseded by the fuse or the cap. Small Arms. Fire-arms of the musket class, to be held by two hands, and those of the pistol class, to be held in one hand, are conve- niently designated small arms, as distinguished from cannon or artil- lery. Irrespectively of mere size, they differ one from another in the character of the bore, the mode of loading, the mode of firing, and the repeating, (i.) Smooth and Rifled Bore. All the muskets, carbines, blunderbusses, fowling-pieces, pis- tols, &c., used formerly to have a smooth bore, circular in section. It has, however, been clearly ascer- tained that if the bore is provided with a series of twisted grooves, to which the bullet will be obliged to conform, the range will be in- creased and the aim rendered more accurate. This important matter is treated under RIFLE ; RIFLING. (2.) Breech and Muzzle Loading. So long as the smooth bore re- tained its pre-eminence, small arms were usually loaded at the muzzle, the bullet being driven down by a ramrod ; but there is now enter- tained a decided preference for breech - loading. Breech - loaders were made and tried two or three centuries ago ; but no armies were supplied with them till quite re- cently. Every Government in Eu- rope is now gradually supplying the infantry with such arms ; for it is proved that a much more rapid fire can be thereby kept up. The English army adopts the Enfield rifle, improved by Snider ; the French adopt the Chassepot ; the Prussians cling to the needle-gun ; SMA 345 SMO Belgium imitates our Snider; Turkey is adopting the Samson rifle ; Austria the Wanzl ; Sweden the Hiigstrom; Russia the Laidley; America the Berdan and the Spen- cer ; Switzerland the Winchester ; Portugal and Italy the Westley Richards* All are discarding their muzzle-loaders, although they differ in opinion as to which breech-loader is the best. Some breech-loaders have openings at the side to insert the cartridge, some at the top ; some turn back the stock with a hinge, and some draw it out, or open the barrel with a screw. In many in- stances the mechanism at the rear end of the barrel is exceedingly delicate and beautiful. (3.) Per- cussion Firing. Under GUN LOCK is briefly noticed the mutation which the old mode of firing underwent ; while PERCUSSION CAPS and CAR- TRIDGE will give some idea of the modern arrangement. It is one among many merits of the breech- loading Snider that the cartridge carries its own detonating composi- tion, and requires no percussion cap. (4.) Revolving or Repeat- ing. It is noteworthy that nfles, breech-loaders, and revolvers were all tried two or three centuries ago, that all were abandoned as fanciful novelties, and that all have now been adopted by military authori- ties. A revolving or repeating arm is one that will fire two or more times with once loading, under cir- cumstances described in REVOLVER. Small Arms Manufacture. Small arms are now made by ma- chinery of the most perfect kind, in well-appointed machine work- shops. The Government factor}' at Enfield is the finest of the kind in England. Though mainly intended for making wkat is known as the Enfield rifle, the machinery can easily be adapted to produce any other kind. More than 2,000 ope- ratives have been employed there at one time, turning out 2,000 com plete rifles per week. Even before the Snider apparatus for breech- loading was added, the original Enfielcl rifle consisted of no less than 57 separate and distinct parts, every one of which had to be shaped individually. Of these, the barrel had 9 pieces or parts, the stock only i, the lock J2, the sight 8, the screw and nipple 15, and what is called the furniture 18. Upwards of 700 distinct operations had to be performed to bring these 57 pieces into proper form and position, viz. : the barrel 78, the stock 25, the lock 137, the sight 74, the screw and nipple 192, and the furniture 202. The present Snider, with the breech- loading apparatus, is necessarily still more complex. If the bayonet is regarded as part of the rifle, there are 4 more parts and 66 more ope- rations. Before making new Snider rifles in any considerable quan- tity, the operations at Enfield have been mainly devoted to converting into breech-loaders the large store of muzzle-loaders previously made. This conversion costs about one guinea per rifle. Besides supplying home demand, our manufacturers of small arms send a consider- able quantity abroad. In 1865 it amounted to 173,000 muskets, 85,000 rifles, 15,000 fowling-pieces, 9,000 plain pistols, and 8,000 re- volvers. Smalt. (See COBALT.) Smelting. (See BLAST FUR- NACE, COPPER, IRON, LEAD, TIN, ZINC, &c.) Smoke Consumption. Coal being cheap in England, not much attention is paid to smoke-consum- ing contrivances ; yet they are well worthy of encouragement, because health and cleanliness, as well as economy, are fostered by their use. Smoke is "produced because there is not a proper relation between the kind of fuel to be burned, the mode of ad- mitting fresh air, and the manner of carrying off the products of combus- SMO 346 SXU tion. Gases and vapours must be produced, as a direct consequence of combustion ; but smoke, which is unused and therefore wasted fuel, need not and ought not to be pro- duced. Inventors have solved this problem in principle in many clever ways. (i.) Smokeless Furnaces. Juckes's is one among many pa- tented inventions for the purpose. The fire-bars form an endless chain, moving so that the fuel is gradually carried from the front to the back of the fire-place. Coal, in regulated quantity, is dropped ( through a hopper upon the front of the fire- bars ; and the air for feeding the nre passes between the bars. The whole area of fire-bars is covered with fuel ; but as the portion last laid on is always nearest to the fiont end, the black smoke from that portion is compelled to pass over more fiercely-burning fuel. This is how the smoke is really con- sumed ; for it burns into flame while passing over the red-hot or white-hot fuel at the middle and back of the stove. Coal is saved, and very little smoke finds its way into the chimney. These two facts have been very clearly proved by the experience of breweries and other large manufacturing establish- ments. Other plans, more or less analogous to Juckes's, have been invented. (2.) Smokeless Open Fires. Many contrivances have been more or less adopted to combine the open fire with the smoke- less action. In Cutler's grate a mode is employed of supplying the fresh fuel at the bottom, so that the smoke from it shall be compelled to pass through the red-hot fuel above, and be changed from smoke to flame. In ArnotVs grate Cutler's plan is improved upon. At the bottom of the grate is a coal-box, open at top, but closed on all four sides ; the bottom moves up and down like a piston, and is made to do so by a rack and lever. The box is filled with coal, and the grate above it is supplied with paper, wood, cinders, and coal. The or- dinary fire in the grate burns at first in the ordinary way; but for the rest of the day it is supplied with coal by occasionally raising the bottom of the box. All the black coal is below the burning coal, and hence the smoke is consumed before it can ascend into the chimney. In Lloyd' 's grate there is a revolving circular tier of bars, one segment of which only is seen open in front ; the smoke from the coal in the hinder segment passes over the hot coal in the front segment, and is con- sumed ; by revolving the apparatus occasionally on its axis, all parts come successively to the front. In King's grate there is an adjust- ment towards the back of the bars which makes the in-coming air assist in consuming the outgoing smoke. In Edwards's grate the chief feature is the substitution of fire-brick for iron in the main parts of the construction, in order to take advantage of the heat - retaining quality of that material ; but there are also contrivances for lessening as much as possible the escape of unconsumed smoke. There are a multitude of other inventions for the same purpose ready for adoption. It is singular to see the disinclina- tion on the part of the public to the use of any material deviation from the old familiar form of open fire- place. If the fear entertained by some engineers that coal will be- come dear on account of our na- tional supply falling short, smoke- consuming contrivances will be more attended to. Snider Rifle, (See RIFLE, RIFLING; SMALL ARMS.) Snuff Manufacture. Snuff being the powder of tobacco, the manufacture of the one is to some extent a supplement to that of the other. The fermentation of the leaf is carried to a great extent (see To- SOA 347 SOA BACCO MANUFACTURE) ; and then the leaf is dried before grinding and sifting. One form of snuff-mill some- what resembles a coffee or cocoa mill, with a continuous rotation of the cone or crusher. Another has a re- ciprocating motion ; the cone making half a revolution in one direction, and then returning, as a means of preventing the teeth from becoming clogged. The ground tobacco tra- vels on an endless apron to a vibrat- ing sieve, where it is sifted ; the fine particles are carried forward into a chest, while the coarser are returned to the mill to be re-ground. An endless variety of snuffs can be pro- duced by combining different kinds of tobacco, using or rejecting the stalk, fermenting and drying them to different degrees, and scenting them with various essences, &c. Rappee, Prince's Mixture, Amers- fort, Lundyfoot, Scotch, &c., are a few among the well-known desig- nations. High-dried snuff acquires a peculiar flavour and odour from the leaves being almost scorched in the drying. Soap Manufacture is, in prin- ciple, very little more than the arti- ficial combination of some kind of oil or fat with some kind of alkali. Such a compound renders soluble in water the dirt and grease which accumulate on the skin, clothes, table- linen, stairs, floors, &c. ; and herein we have the philosophy of washing succinctly expressed. As there are many kinds of oil and fat, and many kinds of alkali, so may there be many kinds of soap produced from them. Soda, the chief alkali in the more useful kinds of soap, was formerly obtained from kelp and barilla ; but now that it is obtained very cheaply from common salt, it has given a prodigious impetus to the soap manufacture. The means of obtaining palm oil and cocoa-nut oil at prices much lower than were before possible has been another in- centive to the advancement of this trade. As a useful general classi- fication, hard soaps are made with soda as the alkali ; soft soaps with potash ; and according as the fat is solid tallow or liquid oil, so is this tendency to hardness or to softness increased. Hence for various kinds are used tallow, lard, dripping, kitchen stuff, fat, fish oil, rape-seed oil, linseed oil, palm oil, cocoa-nut oil, &c., as the oleaginous com- ponent ; soda and potash are the alkalies, but to these are sometimes added common resin. The pro- cesses are as follows : (i.) Boiling. In making common bar soap, the tallow or oil is put into a large cop- per holding several tons ; the lye, or alkaline liquor, is added by degrees, with a little salt, and subjected to three or four boilings with the tallow. It is only gradually that the alkali saponifies the fat, and there is a great (deal of spent lye or waste al- kaline liquor resulting, which the soap-boilers would be very glad to apply to some useful purpose. For yellow soap a little resin is added after the boiling is completed. In mottled soap the peculiar colour results from impurities in the ma- terials ; but in white or curd soap these impurities are removed by sub- sidence. (2.) Framing. When the boiling, settling, &c., are completed, the liquid soap is laded out into frames, quadrangularvessels of wood or iron capable of containing many hundredweight; each frame is built up of many minor frames, superposed one on another, with an easy contriv- ance for separating them. When the soap has solidified by cooling, the frame is taken down piecemeal, leaving the soap standing as a com- pact mass. The mass is cut into slabs 2 to 3 inches thick, by the dexterous use of a wire held by wooden handles at the two ends ; each slab is similarly cut into the bars with which we are all familiar. (3.) Marbled soap is made by add- ing a little sulphide of iron . Windsor SOD 34 SOD soap has olive oil mixed with the tallow and perfumed. Marine soap is made with cocoa-nut oil, which enables it to be used with sea-water. Transparent soap is made by evapo- rating a soda or potash soap after dissolving in alcohol. Silicated soap is made by adding a little sili- cate of soda or of alumina to ordinary hard soap ; it has some of the use- ful properties of marine soap. Float- ing soap is made light by solidifying a kind of lather of hard soap. Yellow soap, as we have said, con- tains resin ; palm oil is usually sub- stituted for tallow. White soap is too hard for domestic use, but forms a basis for many fancy or toilet soaps. Soft soap, much used in the woollen and linen manufactures, consists of potash combined with tallow, and with whale, seal, olive, and linseed oils some or all of them ; the speckled appearance called figging (resembling the interior of a fig) is due to the peculiar way in which the ingredients mix. Toilet soap is made of clarified white soap combined with some or other of an almost endless list of perfumes. It is formed into cakes or tablets by means of a mould and counter-mould, brought together in a lever-press. The soap duty being removed, there are no means now of knowing how much soap is made annually in the United Kingdom. In the last year of the old duty it was 224,000,000 Ibs. Our exports were 25,000,000 Ibs. in 1867. Soda is an oxide of the metal sodium, not much used in the arts ; for that which is popularly known by the name is really a carbonate. Hydrate of soda is the caustic soda used in soap-making. Sulphate of soda, or Glauber's salt, a residuum from certain chemical manufactures, is useful in medicine. Biborate o soda is the substance described under BORAX. Chloride of sodium, for- merly called muriate of soda, is the well-known and invaluable common salt, for which see SALT, SALTERN, SALT WORKS, &c. Carbonate of soda comes for notice in the next article. As for the metal sodium, the basis of all these substances, it is highly prized by the scientific chemist for its very peculiar proper- ties ; but it is not yet much used in the arts in its metallic state. It is liberated in the metallic form by a mutual reaction between carbonate of soda, coal, and chalk, in a sodium furnace devised for the purpose. Soda Manufacture. Carbonate of soda, an invaluable ingredient in soap, glass, and other manufac- tures, is now made almost entirely of common salt, instead of being prepared from seaweed as for- merly. (See KELP.) In Egypt soda is made from a peculiar violet- coloured water, which is left to evaporate. There results a crude carbonate of soda, contaminated with salt, sand, and sulphate of soda ; it becomes much less im- pure, though still crude, by a refin- ing process. In Hungary soda forms in some places by natural efflorescence on the ground ; the powder is scraped off, dissolved iu water, evaporated to dryness, and heated to redness to destroy the organic matter ; but the soda thus produced is still very impure. Com- mon salt, we have said, is now the great source from which soda is prepared. Salt is chloride of sodium, and the first process is to convert this into sulphate of soda. Salt is put into a decomposing fur- nace, and about an equal weight of sulphuric acid is poured upon it. Muriatic acid gas results from the chemical action which goes on in the furnace ; this gas is of some use in making muriatic acid and bleaching powder; but as there is more of it than can be profitably employed, much is let off through lofty chimneys into the atmosphere, where it sadly poisons the air. There remains in the furnace a SOD 349 SOU pasty mass constituting crude sul- phate of soda. This is removed to a furnace called the roasting bed, where, after being heated for some hours, it becomes a whitish mass called salt-cake. To convert this salt-cake into carbonate of soda, it is mixed with limestone and small coal in certain proportions, thrown into a reverberatory black- ash furnace, and exposed to heat and stirring ; various gases are given off, and then the resulting mass becomes black ash, ball soda, or British barilla. This is made to yield about half its weight of soda ash by steeping, evaporating, and calcining. The soda ash or white ash resulting from these numerous processes is the soda so largely used in manufactures ; it is really a car- bonate of soda, not quite pure. It is purified for plate-glass making, and some other delicate purposes, by a further calcination ; while the residue from this calcination is useful in making soap and crown glass. There are many variations in the details of these processes, but the general routine remains pretty constant. The deleterious gases which are given off from the chimneys, and the various compounds which accumulate as a refuse, are two of the blots at our soda-works : experiments are being constantly made to bring these sub- stances into use, but as yet with only partial success. So largely is this important manufacture carried on, that some soda-works will use 500 tons of salt weekly. The whole of the salt used for this purpose in the United Kingdom was estimated in 1865 at 325,000 tons : and that at least 200,000 tons of the alkali were made therefrom. The quan- tity must now be larger than this ; for the Board of Trade tables record no less than 3,200,000 cwt. of soda, in various forms, as having been ex- ported in 1867, irrespectively of the supply for our home manufactures. Soda Water. (See MINERAL WATERS.) Solder ; Soldering. A solder is a metal which, when melted, acts as a cement between two pieces of unmelted metal. There is a great variety of them, known by the names of hard, soft, spelter, silver, white, button, gold, copper, tin, plumber's, pewterer's, and many others. Nearly all the principal metals take part in the composition of solders, and most unmelted metals can be jointed or cemented by one or other of these solders. In all cases the solder is more fusible than the metal to be united. The most frequently employed solder consists of tin and lead, and melts somewhere between 330 and 560 Fahr., according to the proportions of the ingredients. Many variations occur in the mode of conducting the operations. The edges of the two metals must be well cleaned, and then heated; the solder must be melted ; a flux of borax, c., is often needed to insure the ad- hesion of the solder to the two pieces of metal, and soldering-irons of various kinds are required. The name of autogenous soldering is given to a process wherein neither solder nor flux is used. A mode of burning the edges of the metal together is adopted by the aid of intense heat. Soot is unburned carbon, the solid part of smoke. Peculiar kinds of soot yield ivory-black and lamp- black. Sounding: Apparatus. Among many instruments for measuring the depth of the sea is Ericsson's sound- ing lead, intended to act inde- pendently of the length of the lead- line, and without the necessity of rounding the ship to the wind. The instrument consists of two large tubes ; a chamber is placed immediately behind, and connected by means of a small bent orifice to the upper extremity of one of them ; sou 350 SPE while the top of the second is con- nected by a similar orifice to a third small tube suspended in the centre of the chamber. A stop-cock is placed at the lower end of the glass tube, for the purpose of cutting off communication if necessary. The lead, bent to the line, is lowered into the sea ; as it sinks, the water enters the chamber, and gradually rises in it and in the suspended tube ; this causes an increased pres- sure upon the air, which is thereby driven through the orifices into the glass tubes. The tube which is connected with that in the chamber will be entirely filled with the air thus forced into it from the sus- pended tube ; the water will conse- quently rise, and its reading may be observed upon a graduated scale with which the instrument is fur- nished. The contents of the cham- ber being much greater than those of the tube suspended within it, the air with which it is filled will not be compressed sufficiently to admit water into the glass tube connected with it until the lead has descended 25 fathoms. For depths less than this limit the instrument is very convenient ; for greater depths a heavy weight, or deep-sea lead, is required, the depth of the sea being measured chiefly by the length of line run out, as in the ordinary lead- line. Some lands of sounding ap- paratus have a provision for bring- ing up specimens of mud, sand, &c., from the bottom of the sea. There is a rod, to which are fast- ened on hinges two hemispherical nippers ; by the action of a supple- mentary disengaging weight, the nippers are closed on reaching the ground, and retain the earthy de- posit till brought up to the surface. Sounding- Boards. A remark- able speciality in the manufactures of Bohemia is that of sounding- boards for pianofortes. The fine, soft, smooth-grained, and sonorous wood of the silver pine, which there grows in great perfection, is espe- cially suited for making the large, thin sounding-boards of our piano- fortes and other musical instruments. Many of the principal London makers are supplied from this source. One firm alone, at Mader- hausen, exports 40,000 to 50,000 such boards every year. Specific Gravity. This matter is of some importance in the arts, though not so much as in scientific investigations. When the relative weights of different substances are designated by their specific gravity, it means that water of average tem- perature and pressure is taken as a standard. Water, for example, being i - o, and manganese being 8-0, it means that a cubic foot of manganese weighs 8 times as much as a cubic foot of water. Metals range from 23-0 (iridium) to 0-9 (potassium) ; woods from 1-3 (lig- num vitae) to 0*24 (cork) ; liquids from 1-84 (sulphuric acid) to 072 (sulphuric ether). Gases are com- pared with atmospheric air, and range from 4-34 (hydriodic acid gas) to 0-07 (hydrogen). Spectacles. The making of spec- tacles is a large department of trade at Birmingham and Sheffield. So long as the frames were made of gold and silver, the making was distri- buted pretty evenly among our large towns ; but when horn and tortoise- shell, still more when steel and iron became the prevalent materials, the manufacture naturally centred at the two towns above named where much greater facilities are found. By far the larger portion of spectacles are now made of steel wire, the shaping, soldering, and riveting of which give rise to the display of much in- genuity. By variations either in the frames or the lenses, many special j kinds are made. Spectacles that may be used as hand-glasses or double eye-glasses ; a folding double eye-glass that may be used as specta- cles, by connecting the two hoops SPE 35i SPE with a helical steel spring ; specta- cles with the centre only of each glass transparent, to aid in curing squinting ; spectacles in which the two glasses have slightly different refractive powers, to suit eyes of un- equal focus ; spectacles in which the frames, for strength, are cut out of a solid piece of sheet-steel, instead of brazing or soldering ; spectacles with two different powers in each glass, one for viewing near objects and one for distant these are some of the varieties which the manu- facture presents ; but the bulk of the trade is in ordinary steel spectacles, at a few shillings per pair. Speculum. The speculum, or polished metallic reflector of tele- scopes and microscopes, is one of the most highly-finished products of the metal-working arts ; the conditions of whiteness of colour, perfection of curvature, and beauty of polish being so indispensable. The late Earl of Rosse made the specula for his figantic telescopes of the best re- ned copper and block tin, in the proportions of 126-4 parts of copper to 58-9 of tin. In order to avoid the difficulty experienced by Sir W. Herschel and others in coating, grinding, and polishinglarge specula, he resolved to make his in pieces, soldered to a backing of brass ; the brass contained more copper than usual, in order that it should expand and contract just in the same degree as speculum metal. The brass back- ing was cast in eight pieces, each an octant of the whole disc, flat on the upper surface and cellular on the lower; and these eight were strongly bolted together, forming a mass several inches deep, and weighing several hundredweight. The upper surface was turned in a lathe, to a con- cavity depending on the focus. The speculum metal was cast in sixteen separate pieces, none of them exceed- ing 9 inches square ; this casting was done with the most rigorous precision, the upper surface of each piece being I concave and the lower convex. The | sixteen pieces of speculum metal 1 were then fixed down upon the brass backing by a mode of soldering ex- pressly devised for the purpose; and the edges or seams were rendered invisible. In other instances the earl succeeded in casting large specula all in one piece. The grinding and polishing of specula are usually performed by hand, by rubbing over the concave surface with a convex surface of some other substance ; but the Earl of Rosse in- vented a machine whereby grinders and polishers of spherical curvature worked over the speculum with un- erring regularity, producing spheri- cal concavity more nearly mathe- matically true, perhaps, than human skill had ever before attained. For the earl's 6-feet speculum 4 tons of metal were required, melted in three crucibles ; when cast, the mass was kept gradually cooling for six weeks, in an oven which began at 900 Fahr., and cooled down to the tem- perature of the air. And then suc- ceeded the laborious processes of grinding and polishing. So numerous were the liabilities of failure, that the earl broke or spoiled five of these great specula in succession, and only succeeded with the sixth. Very ingenious grinding and polishing machines have been invented by Mr. Lassell, Mr. Grubb, and other makers of large specula. They con- sist of trains of wheel-work, so planned that a grinder or a polisher may make a very intricate series of movements all over the surface of the speculum, pressing equally and giving equal curvature to every part. Messrs. Grubb, of Dublin, made in 1868 a splendid speculum, 4 feet diameter, for the great Melbourne telescope. Spelter. (See ZINC.) Spermaceti is a curious sub- stance obtained from the sperm or South Sea whale. In the front of the skull of this enormous animal is SPE 352 SPI a cavity called the case, which is filled with a semi-fluid substance that hardens on cooling. This substance, of which there is sometimes as much as 300 to 400 gallons in one animal, consists of a yellowish mixture of spermaceti and oil. By draining, squeezing, and purifying, the two are separated, and the spermaceti appears as a beautiful pearly white wax, used for candles and other pur- poses. Sperm Oil. This is a superior kind of whale oil, obtained from the ' South Sea instead of the Greenland ' whale. The blanket of the one, ! like the Uubber of the other, is the \ oily fat between the skin and the i muscles, but thinner ; and the oil is { obtained from it nearly in the same i way. (See WHALE OIL.) Spices. A little is said on this subject under CINNAMON, GINGER, NUTMEG, PEPPER, &c. Our total imports of spice in 1867 amounted to no less than 25,000,000 Ibs. Spikes, as means of fastening, have recently received a good deal of attention. They owe their effi- ciency to the adhesion of the spike to the wood into which it is driven, which adhesion resists the with- drawal of the spike. On the Ame- rican railways, where slight rails are often simply spiked down upon wooden sleepers, the form of the spike and the kind of wood are found to have much to do with the firmness of the holding. Spikes known by the names of narrow flat, -wide flat, grooved and swelled, grooved and notched, plain cylin- drical, square hammered, &c., are used ; and pains have been taken to ascertain the conditions under which each kind is likely to render most service. Spindle. (See SPINNING.) Spinet. (See PIANOFORTE.) Spinning-. The twisting of mi- nute filaments into a thread or yarn for weaving is almost as old an art as weaving itself; almost, because some of the vegetable fibres can be spun without weaving. In all the varieties with which we are best acquainted cotton, flax, hemp, jute, silk, wool short filaments are converted into long, thin into thick, straight into twisted ; various modes of preparation initiate these changes, but spinning is the finish- ing process. Under the names of the principal textile goods these pre- paratory operations are noticed, and also some of those connected with the spinning ; but a few general obser- vations may be useful here, (i.) Dis- taff and Spindle. Thesimplestspin- ning process is with the distaff and spindle, the method of poor peasants of the present day, and in former days the only one. The distaff, held under the left arm, is a stick about a yard long, with a cleft or fork at the top, on which carded wool, cotton, &c., are wound. The spindle, about a foot long, is another stick with a slit at the top. With the thumb and finger of the right hand, fibres are drawn out from the distaff to a certain length or dis- tance, and twisted spirally one around another; the yarn, when thus spun or twisted, is wound round the spindle. (2.) Spinning Wheel. In order to expedite the process, a spinning-wheel was in- vented to supersede the distaff and spindle. Here the spindle is made to rotate by means of a wheel turned by hand, greatly increasing the rapidity. Soft fleecy rolls or card- ings of prepared fibres, a foot or so in length, are attached one by one to the spindle ; they are drawn out by the fingers of the left hand, and stretched and twisted by the rota- tion of the spindle and wheel. A coarse thread is thus made, which a repetition of the process converts into fine thread. (3.) Spinning- jenny. James Hargreaves in- vented an ingenious machine, which makes one wheel turn many spin- dles ; tin's he called the spinning- SPI 353 SPI jenny. He improved on this from time to time, till he made one wheel work 80 spindles. The spindles are placed upright. The 80 rovings from the 80 spindles are drawn out horizontally, and clasped by two flat edges which meet together. This clasp travels to and fro on four small wheels ; during the draw- ing away from the spindles the roving is stretched and attenuated into a thin yarn, to which a twist is given by the rapid revolution of all the bobbins ; and when the clasp is driven the other way, these lengths of spun yarn become wound round the bobbins. (4.) Spinning Frame. Still further advances were made. Richard Arkwright invented his spinning-frame to do that which could not be so well done by Har- greaves' spinning-jenny. To spin by rollers had been more or less attempted by Wyatt, Paul, Highs, and Kay; but Arkwright (once a poor barber at Preston) was the first to give practical realisation to the idea. His machine was called the -water-frame, because it was first worked by water power ; and the yarn, a harder and firmer thread than could be made by the jenny, obtained the technical name of water-twist. (5.) Throstle Spin- ning. After many changes and improvements, and the substitution of steam for manual and water power, Arkwright's process settled down into what is now called throstle-spinning. The bobbins full of prepared roving are placed on the top of the throstle- frame. Rollers and bobbins and flyers draw out the fibres, elongating and attenuating them, and at the same time twisting them tightly into a compact yarn, well adapted for the warp or long threads of woven goods. In the technical language of a cotton-mill, the throstle is used for the hard coarse yarns up to about No. 40. (6.) Mule Spin- ning. Samuel Crompton invented a very beautiful machine, in which he combined the jenny spinning of Hargreaves with the roller spinning of Arkwright; he called it the mule-jenny, and the process mule- spinning. In this mule action the bobbins containing the rovings are on a fixed frame; the spindles by which the rovings are to be twisted into yarn are on a movable frame ; the movable frame, by travelling 4 or 5 feet outward, then an equal distance backward, and so on alter- nately, stretches and attenuates che threads. The two sets of opera- tions, elongating and spinning, suc- ceed each other with exquisite regu- larity; 600 or 700 threads, all ranged parallel, being managed by self-regulating mechanism. Mule yarn, as it is technically called, being twisted more softly and care- fully than throstle yam, is suitable for the weft or cross-threads of coarse goods, and for both warp and weft of fine goods. (See fur- ther under COTTON, FLAX, HEMP, JUTE, SILK, WOOL, for minor diversities in the spinning process.) Spirit ; Spirits. The vague name of spirit is given to a number of liquids, many of which are other- wise called essences, essential oils, alcohols, and ethers. The word in the plural, spirits, more frequently refers to alcoholic beverages, pre- pared by various distillatory pro- cesses. Whiskey, for instance, is the unsweetened spirit of grain, mostly malted barley ; gin is an English spirit, rectified or flavoured with vegetable extracts and juices of vari- ous kinds ; Hollands or Geneva is made by the Dutch from barley-malt and rye-meal, flavoured with hops and juniper berries; rum is dis- tilled from the molasses which result from sugar-making; and brandy from the husks and stalks of grapes left from the wine manufacture. There are also arrack, toddy, beet- root spirit, potato spirit, &c. (See under these several headings, and A A SPO 354 STA also DISTILLING.) In 1867 there were about 23,000,000 gallons of British spirits distilled, and about 12,000,000 gallons of foieign spirits imported. Sponge is either an animal or a vegetable : naturalists are not agreed which, so low is it in the scale of organic nature. This substance is used in the arts for its well-known qualities as an absorbent of liquids. Spring; Spring- Balance. The elasticity of metals gives rise to a great variety of springs, which re- ceive shapes depending on the pur- poses to which they are to be applied. deck springs, watch springs, balance springs, coach springs, are merely a few among many varieties. A spring balance is a coil of wire, the stretch- ing out of which is made to mea- sure the force which stretches it. Spruce, Essence and Beer. The young shoots of the black spruce fir, when boiled and concentrated, yield essence of spruce; and this essence, when combined with sugar, yeast, water, and flavouring spices, constitutes spruce beer. Stained Glass. It is not always that this designation is correctly used ; for sometimes the glass is only painted on the surface, not stained throughout the substance. Real stained glass is simply coloured glass; and the colour is almost always given by adding certain metallic oxides to the other ingredients. Many ancient nations were acquainted with modes of making coloured glass ; but it is not certain what kinds of chemical agents they employed. Oxides of gold tend to produce red tints ; those of copper tend towards green ; those of manganese purple; and so on with other oxides and chlorides. The glass-stainer ought, therefore, to possess a good knowledge of the chemistry of colours. Three varieties of such glass may be thus dis- tinguished : (i.) When glass is to be stained throughout, the colour- ing ingredient is mixed with the sand, alkali, and other substances in the glass-pot, and melted all to- gether ; or else good white trans- parent glass is remelted, and the me- tallic oxides combined with it in that state. (2.) When it is to be stained on one surface only, the glass-blower has two pots in the furnace, one with transparent and the other with co- loured glass. He dips his blowing tube into the former, and takes up the requisite quantity of glass ; after rolling and setting it a little, he dips it for a moment into the coloured flass, of which he takes up a thin 1m. The blowing and finishing are then proceeded with, leading to the production of glass with a thin coloured film on a white foundation. (3.) When it is to be painted, the metallic oxides are ground up with oil of turpentine and other substances into a paint or pigment, which is applied with camel-hair pencils. The paint is nearly always of a dirty muddy colour; and considerable ex- perience is needed to determine what will be the tint eventually produced. The glass, when painted with any device, is put into an oven, and heated to such a degiee that the metal of the paint fuses and incor- porates itself with the surface. Some- times the painting is effected by sprinkling metallic powder on a gummy medium, and then baking it. Various kinds of fancifully-coloured glass are briefly noticed under AVENTURINE. (See also ENAMEL.) Stamping. Metal (in thin sheets), leather, card, paper, cloth, and other substances are now stamped with some pattern or other in enor- mous variety. There is always some kind of die, with or without a counter-die ; and the pressure is produced by hand, by treadle-press, by screw-press, or by hydraulic press, according to the degree of force re- quired to be used. Stamping is now very extensively adopted in jewellery, for the precious metals as well as for cheap imitations: there is a saving STA 355 STA of material as well as of time, and great precision in form. The French have recently made much advance in this art. Standard; Sterling 1 . In order to insure that the English coins shall be reliable in quality, certain stand- ards are adopted, to which they must severally conform. All are alloys or mixed metals, although there is in each some one metal that greatly preponderates. Standard or sterling gold consists of -5-5- gold and Y- copper ; standard or sterling silver of f silver and ^ copper ; and standard bronze (lately sub- stituted for the old copper coinage) i a % copper, itfo tin, and ^ zinc. Then there are standards of weight: 934^ sovereigns must weigh 20 Ibs. troy ; 66 shillings, I Ib. troy ; and 79 bronze halfpence, I Ib. troy. The coiners at the Mint, not being able to insure absolute accuracy, are allowed a certain margin of error called the remedy. This error or remedy from the standard is drawn out to many places of decimals in the Mint regulations, seeing that the assayings and weighings are con- ducted with extreme minuteness and nicety of detail. (See COINS; MINT; PYX.) Alloys are adopted instead of pure metal for coins, as being harder and better able to with- stand wear and tear. Sterling sil- ver for coinage is the same in quality as standard silver for silver plate. Irrespectively of coinage, standard yards, gallons, bushels, pounds, ounces, &c., have been prepared for the Government, as authoritative models from which others may be made for commercial purposes ; and these standards have a legal autho- risation given to them by Acts of Parliament. In no department of mechanical art, or science applied to practical purposes, is more scrupu- lous care observed.than in the manu- facture of such standards. Every influence which temperature and humidity can exert in expanding or shrinking solids or liquids Is taken into account ; and the skill of some of our most eminent 'men is brought into requisition, to insure the utmost possible accuracy in every part of the operation. Starch is a kind of flour or farina that exists in a large number of seeds, roots, tubers, stems, fruits, and lichens. It forms with boiling water a kind of mucilage which cools down into a jelly ; and it is to this mucilaginous quality that it mainly owes its usefulness in the arts. Wheat, potato, rice, arrowroot, sago, and tapioca are the chief kinds of starch producers. Ordinary starch is mostly made of wheat. The grain is coarsely ground, steeped for several days in water, and fermented ; the fermented liquor is allowed to settle, and the starch-water is sepa- rated from the bran. A number of other processes ensue, until the starch, as a nearly white residue, is produced in the form of cakes, which crack into the small pieces so familiarly known in the laundress's starch. To manufacture starch pro- fitably on a large scale, numerous patented processes are adopted. Statue Casting-. Bronze busts, made hollow from a solid model, are produced somewhat as follows : The mould must be in at least three pieces, often much more, for articles presenting such varieties of curva- ture and under-cutting as statues, statuettes, busts, equestrian figures, and the like. These pieces are made separately, each from one par- ticular part of the model, and all with their edges so nicely adjusted as to permit the making of clean joints. The mould, when the pieces are fitted together, deter- mines the exterior form and mark- ings of the cast ; and a core is needed to settle the thickness of the metal. A pit or cavity is formed in sand, and filled with a liquid paste made of plaster of Paris, sand, and water; the mould being in the STE 356 STE middle of the pit. At a particular stage the mould is removed piece- meal, the core dried and burned, and pared away in every part to a degree equal to the intended thick- ness of the metal. The surface of the core does not require any par- ticular finish, as it merely repro- duces, in reverse, the inner or hidden surface of a hollow statue. The core and mould being properly adjusted, molten bronze is carefully poured into the space between them ; when this has cooled, the pieces of mould are removed from the exterior, and the core from the interior. The bust or statuette is then finished by the chaser, to re- move the markings of the mould- joints. Steam. The vast importance of steam in the arts depends mainly on these two circumstances : that the change of condition from water to steam, and vice -versA, is very easily brought about ; and that the difference in bulk between those two states is enormously great. Visible steam, as from the mouth of a tea-kettle, is not really steam ; it is a mass of minute particles oi water ; steam, properly so called, or aqueous vapour, being quite trans- parent and invisible. The density of dry air and that of steam, at an equal temperature and under equal pressure, are as 8 to 5. The dampest air is, under equal tempe- rature and pressure, the lightest ; and this is one reason why the baro- meter often falls in damp weather. The mechanical properties of steam, so long as it remains really steam, are identical with those of air ; but the extreme susceptibility to change of condition under change of tem- perature often veils this similarity. Steam is rising from water at all temperatures ; but as, at a given temperature, the steam can only attain a given density and pressure, its formation at low temperatures is slow and hardly to be detected. When a givea bulk of steam is confined within a vessel of definite dimensions, change in its tempera- ture leads to the three conditions of sub-saturated, saturated, and super- heated steam ; distinctions very im- portant in the working of steam- engines. When water at 212 is producing steam, the steam is at the ordinary pressure of the atmo- sphere ; becoming high-pressure or low-pressure steam when the tem- perature exceeds or falls short of this limit. Taking 30 inches of mercury as the pressure of the atmosphere, steam at 76 Fahr. has a pressure of only i inch : 105, 2 inches; 127, 4 inches; 162, ic inches ; 180, 15 inches ; 192, 20 inches ; 204, 25 inches. These are all examples of low-pressure steam. High-pressure, on the con- trary, presents the following figures : 226, 40 inches ; 248, 60 inches ; 266, 80 inches ; 280, 100 inches ; 326, 200 inches; 361, 400 inches; 418, 600 inches. The last named would be called "20 atmospheres." These figures show how great is the expansive or bursting tension of steam when heated much beyond 212. Steam and water can co-exist at almost any temperature ; but the steam always contains more heat than the water, although the thermometer fails to detect it. There is a large amount called latent heat, which is an essential condition in the exist- ence of steam, but of which the thermometer tells us nothing. All these matters concerning the tem- perature, density, pressure, and latent heat of steam are of great importance in the theory and action of ihe steam-engine. Steam is much employed, also, in heating water, melting solids, and boiling solutions of various kinds. Steam Carriag-e. (See LOCO- MOTIVE, RAILWAY and ROAD.) Steam Engine. If there is one invention which deserves to be called the greatest of all, in relation STE 357 STE to its influence on material progress, perhaps it is the steam-engine. Even those who would name in preference the printing-press must bear in mind that, without the steam- engine, the power of the press in diffusing knowledge would always have been limited. The action of the steam-engine depends virtually on this that a cubic foot of water be- comes i, 600 or 1,700 cubic feet of steam when it exchanges the liquid for the aeriform state ; and that the violent disturbance of air, to make room for this steam, gives motion to the pistons, shafts, beams, cranks, wheels, &c. The projects of the Marquis of Worcester, Savory, Moreland, Pepin, Newcomen, and others before the time of Watt, gradually habituated the minds of inventors to recognise the fact that this expansion of steam into water is a great and available source of power, and that a country in which coal is cheap ought to develop this power into usefulness. Then came James Watt's discoveries and in- ventions, just about a century ago notably the condenser, and the ad- mission of steam both above and below the piston. Numberless and beautiful as have been the subse- quent inventions, it remains true that the fundamental characteristics of the steam-engine are nearly as Watt left them. Whatever may be the external form and general arrangements of the several parts of a steam-engine, the classification into condensing and high-pressure is clear and convenient. A condens- ing engine, or, with equal correct- ness of designation, low-pressure engine, has such an arrangement of cylinder that, after the piston has been driven one way, the steam escapes into a vessel called the con- denser, where a spray of cold water re-condenses it. A vacuum, more or less perfect, being thus made in the condenser, the cylinder is pre- pared for the action of a new por- tion of steam in pressing the piston downwards; and so the process goes on, the steam used in causing one movement of the piston being removed by condensation before a renewed supply is admitted to act on the other side of the piston. Valves of various kinds and beautiful action regulate the ingress and egress of steam ; gauges denote the degree of vacuum and other parti- culars ; while pumps and pipes carry away the water which collects in the condenser. A high-pressure or non-condensing engine has no con- denser and no air-pump ; it is smaller and cheaper than the con- densing engine. On the other hand, it is obliged to be worked at a higher pressure of steam, a cir- cumstance attended with certain disadvantages. The steam, after being admitted from the boiler into the cylinder, presses the piston along in one direction, but as there is no condensing and no vacuum, the steam can only escape into the open air. This it must do before a new supply of steam can enter to press the piston in the opposite direction. One side or the other of the piston is always in communication with the atmosphere, the pressure of which must be overcome before the next movement of the piston can be effected. Hence there is a great waste of power arising, as compared with the condensing engine; and some of the machinery has to be made additionally strong to bear the force of the high-pressure steam. On the other hand, when steam has once been raised to a certain tem- perature, a small increase of heat will produce a large increase of power ; the greater the power raised, the less relatively is the quantity of fuel necessary to raise it, other things being equal. Nevertheless, the total consumption of fuel is about 15 per cent, less in a condens- ing than in a high-pressure engine a circumstance that often deter- STE 358 STE mines the choice of the former in places where fuel is dear; while, on the other hand, where water is scarce, the high-pressure becomes the more useful of the two. Al- though condensing and non-con- densing are the principal designa- tions, there are others which must be briefly adverted to. A compound engine partakes of the qualities of the other two. The steam, having been somewhat expanded in a small cylinder, is admitted to a larger one, where it works the piston, and passes into a condenser. A beam- engine is one of various forms adopted, not in the n ing the steam, but in power to work the fly- is a horizontal beam at the top, having a connection with the piston- rod at one end and the crank- shaft at the other. It is claimed that in this form the cylinder and piston wear better ; but there are certain disadvantages which lead to other forms being more and more generally employed. A horizontal engine has the cylinder horizontal, and the fly-wheel worked without the intervention of a beam. Its superiority over the beam engine consists in the following items : it is less heavy; it occupies less room: it is more simple in construction and in working ; it is less liable to break down ; the piston can be worked more rapidly ; finally, it costs less to make, and less to build a foundation on which the engine may rest. An oscillating engine has the cylinder so placed as to oscillate like a pendulum, and thereby conform to the crank, the motion of which is derived directly from the piston-rod. A rotary engine has no cylinder and piston of the usual form, no reciprocation of up-and-down or to-and-fro motion ; the steam acts at once upon a revolving apparatus, which communicates with the fly- wheel. Disc engines, vertical en- gines, direct-action engines, trunk engines, crank-overhead engines, are other designations which have been more or less employed ; and there is, indeed, no practical limit to the diver- sities which the working apparatus may present. The most useful generalisation, perhaps, is this that all locomotives are non -con- densing, and that by far the larger number of other steam-engines are condensing. At the Paris Exhibi- tion of 1867 there was a steam- engine which won high encomium from the engineers who closely studied it. It obtained the complex name of the Corliss- Allan- Porte r- Whitworth engine, having been invented by Corliss, improved by Allan and Porter, and made by Whitworth. Its main peculiarity consists in an exquisite adjust- ment of valves, controlled by an automatic governor ; and its main purpose is to economise every atom of steam, by allowing none to escape without doing its allotted quota of work. It is an American invention, and exemplifies one among many ways in which the Americans seek to economise fuel, which is dearer with them than with us. Mr. Cola gives a very useful tabulation, in which are stated, for a steam-engine with appendages of a given amount of horse power, the diameter of the cylinder, the length of the stroke, the length and dia- meter of the cylindrical boiler, the total weight, and the total cost. His range of sizes is from 4 to 50 horse power, and the prices stand thus : !J Cos.. Hoe Cost . Power. 4 ^96 22 /520 6 144 24 576 8 192 26 624 10 240 28 672 12 288 30 720 14 336 35 840 1 6 384 40 980 18 432 45 1,075 20 480 50 1,120 STE 359 STE The cost, it will here be seen, never deviates far from ^24 per horse power, within these limits. Larger sizes are more special in character. These figures are for horizontal high-pressure engines. Condensing engines cost about 6 per horse power additional. A portable steam-engine, with boiler, on wheels, ranges from ^140 for 4-horse up to ^505 for 2O-horse. A patent fuel-economiser costs from j"jo to ^" I2O > according to size of boiler. Various subsidiary details are noticed under BOILER; EXPANSIVE WORKING; FUEL ECONOMISER ; INDICATOR; INJECTOR; LOCOMO- TIVE, RAILWAY and ROAD; SAFETY VALVE, &c. Our exports of steam -engines in 1867 were valued at ,2,000,000. Steam-engine Averages. A useful mode of tabulating the action and value of steam-engines is adopted in Cornwall, where the costliness of coal renders economy very important in everything con- nected with the furnaces, boilers, cylinders, pistons, and valves. All the engines of one class, or applied to one kind of duty, are placed to- gether in a group, and the average struck for each group. A recent computation gives the following re- sults : Pumping engines, load per square inch of piston, 12 Ibs.; strokes per minute, 5 ; water drawn up per minute, 4,000 gals. ; duty, or weight lifted i foot high by the consump- tion of I cwt. coal, 60,000,000 Ibs. ; consumption of coal per horse power, 4 Ibs. Whim-engines : depth of raising, 900 feet ; weight drawn up from this depth by using I cwt. coal, 50 kibbles of 3 cwt. each ; duty, 16,000,000 Ibs. Stamping engines: strokes per minute, 14 ; duty, 3 1, 000,000 Ibs. The average duty of pumping engines in Corn- wall rose in twenty years from 28,000,000 Ibs. to 60,000,000 Ibs. ; whereas in individual cases it has occasionally reached 100,000,000 Ibs. There is a source of confusion in some of the tables relating to this subject, in the adoption of cwt. in some instances and bushel in others, as the unit of coal. Steam Farming-. The steam- engine is becoming a valuable ad- junct in farming. From the very earliest days of the steam-engine, projects have been entertained to this effect ; and many ingenious ma- chines have been tried the earliest inventors, as usual, failing, but sup- plying useful hints for their suc- cessors. Fowler and Howard have been the most successful inventors hitherto. Fowler's steam-plough comprises a locomotive, or engine on wheels, placed at one end or side of a field ; an anchor deeply fixed in the ground at the other end of the field ; an ,endless wire rope ex- tending from the anchor to a drum or wheel acted upon by the engine ; and a plough or ploughs attached to the wire rope. The ploughs are so made as to act in both directions ; and thus the steam-engine, pulling at both sides of the endless wire rope in turn, permits the ploughing to proceed without turning the plough at the end of each line of furrow. Howard's apparatus has the locomo- tive at one corner of the field, and a system of wire ropes extending all round the field. Fowler's, Howard's, Coleman's, Aveling and Porter's, and other forms of steam apparatus, have their several features of merit. Other modes of treating the land besides actual ploughing are possi- ble, when once the substitution of steam power for horse or ox power is effected ; and thus there may be steam-cultivators, steam- hetrro-ws, &c., as well as steam- ploughs. Steam Hammer. How to work a hammer with steam instead of manual power, with an immense rapidity of blows, and with any de- gree of force from a gentle tap to a tremendous concussion, was a pro- STE 360 STE blem which Mr. Nasmyth set before himself; and admirably has he solved it. A particular engine-shaft of large diameter being required in 1837, it was found that no mechanical ham- mer then in existence could deal blows formidable enough to forge it. Mr. Nasmyth set his fertile brain to work, and by degrees perfected a steam-hammer, which was not, how- ever, actually made until 1843. In its latest developments this is cer- tainly one of the most important machines known to the mechanical engineer. As usually constructed, there is a mass of iron called the hammer-Hock, weighing sometimes several tons ; and a smaller mass fixed to the lower part of it consti- tuting the hammer. This hammer works upon an anvil, embedded in the upper surface of a ponderous mass called the anvil-block, so sup- ported by a solid foundation as to be able to bear almost any amount of concussion. Rising from the ground are two standards, so ar- ranged as to retain the moving part of the mechanism between them ; these standards are joined at the top by a linte*. A small steam-engine is upheld mainly by the lintel, with steam-cylinder, valve-box, piston-rod, steam-chest, and other accessories, all specially adapted to this kind of work. The steam-boiler may be at any convenient distance, and steam brought from it through a jacketed steam-pipe. The arrangement is such that, when steam enters the cylinder below the piston, the pis- ton is driven up, and drags up with it the hammer-rod, hammer-block, and hammer ; when the steam es- capes through a valve to the waste- pipe, the hammer and its append- ages fall with tremendous force by their sheer weight. There is self- acting gear which arrests the rise of the piston at any required height, thereby giving to the hammer any desired depth of fall. When once adjusted, the hammer will continue its lusty blows with uniform power ; a slight change made by an attend- ant will vary either the rapidity of the blows or height of the des ent, or both, and another slight move- ment will stop the action altogether. AH the detailed mechanism which enables one single workman to do this is exceedingly beautiful, espe- cially that in which some of the steam is made to act as an elastic cushion or spring. We have seen the same steam-hammer crush an iron bar an inch thick, and then, by a simple movement of a handle, give taps so gentle as to descend upon a nut without cracking the shell. The first steam-hammers that were made had hammer-blocks of about \\ cwt. each ; but the ma- chine has since been vastly increased in weight and power, insomuch that there are now examples varying from 2 cwt. to 20 or 30 tons. At Krupp's celebrated steel-works at Essen, in Prussia, there is one steam- hammer said to be 50 tons in weight, with a cylinder 6 feet in diameter ; the blows which it hurls are received upon an anvil weighing no less than 1 85 tons. There are nearly fifty steam- hammers, of various sizes, at these gigantic works. A duplex steam- hammer has been invented, and par- tially brought into use, having two horizontal cylinders, and two ham- mers which approach each other horizontally, squeezing and thump- ing any object (such as a mass of red-hot iron) that comes between them. Steam Man. Early in 1868 the Americans introduced a mechanical novelty under the name of the steam- man. It consisted of a gigantic figure of a man, about 8 feet high, with a furnace in his mouth, a boiler in his chest, a smoke-vent through the crown of his hat, and a steam- whistle in his mouth. His legs, full of cranks, levers, and springs, moved somewhat in the manner of human legs, and on a level road would tra- STE STE vel a mile in two minutes. He drew a small carriage after him. Whether any combination of levers can equal the rolling of a pair of wheels in utilising steam power for road loco- motion is rather a doubtful problem. Steam Vessel. If a steam- engine can make a wheel and a shaft rotate, it can obviously give rotation to some kind of wheel dipping into water ; and, if the wheel has pad- dles at the periphery, this rotation may be made to propel a ship or boat. This idea early took hold of men's minds. When James Watt began his great improvements in the steam-engine, about 1769, the steam navigators set to work ; and by the successive labours of Symington, Taylor, Miller, Fitch, Rumsey, Bell, Fulton, and others, the system was fully established as a sound one by about the year 1812. What has since resulted every one knows merchant and passenger steamers tip to the magnitude of the un- equalled Great Eastern ; superb line- of-battle timber ships such as the Duke of Wellington ; and ponder- ous iron-clads of the Northumber- land and Hercules kind all pro- pelled by steam power. AJmost all the forms of engine mentioned under STEAM ENGINE have been tried in boats and ships ; and it is by no means yet decided which form is the best. In the Great Eastern the engines which work the screw are entirely different in build from those which work the paddles. The ope- rations noticed under SHIP BUILD- ING require modification when the ship is to be a steamer, but the gene- ral principles still prevail. (See, for modes of propulsion, NAUTILUS PROPELLER ; PADDLE WHEEL ; SCREW PROPELLER.) Stearine is nearly allied to stearic acid. This acid is a complex union of carbon, hydrogen, and oxygen, obtained from various fatty matters, and belongs to the class of solid fatty acids. It exists in mutton suet and most solid fats. When pure, it is a tasteless and inodorous wax- like substance. It is obtained by various processes of saponifying, de- composing, pressing, crystallising, &c. It is used in making a well- known form of candle. (See CANDLE MANUFACTURE.) Stearic acid forms stearates by combination with various other bodies. The stea- rates of the alkalies easily make a good frothy lather, and are, in fact, among the principal chemical ingredients in soap. Stearate of lead is used in medicine. There are three modes now adopted of manufacturing stearine. (i.) The fatty matters are treated with about 14 per cent, of lime, thus produc- ing various kinds of lime-soap, in- soluble in water, and setting free glycerine, which is dissolved in water. (2.) They are treated with sulphuric acid, followed by distillation. (3.) They are decomposed by the com- bined influence of water, heat, and pressure, producing a white stea- rine, and an acid oil of good quality. M. Leon Droux displayed some im- proved apparatus for this manufac- ture at the Paris Exhibition, 1867. Steatite, or Soapstone, is a pe- culiar mineral, consisting chiefly of silica and magnesia, varying from white to reddish yellow, easily cut, with difficulty broken, and soft and greasy to the touch. It is used in the porcelain manufacture ; by gla- ziers in marking on glass, and by tailors for marking on cloth ; in making French chalk, Venice talc, rouge, powder for extracting grease spots ; in imitating engraved stones ; and in many other ways. Steel. If it were possible to ex- pel all carbon from wrought or cast iron, the metal would still be iron, one of the simple substances of scientific chemistry. But the same would not be the case with steel, which is always a mixture of iron and carbon, both constituents being indispensable. Steel differs from STE 362 STE quantity bined with it, and in the mode of combination. All manufactured iron, whether wrought or cast, contains some carbon ; but in steel it is so combined as to constitute a carburet of iron. Very little is needed, butthis little, when chemically combined, renders the iron harder, denser, smoother, finer, and more elastic ; it takes a whiter colour and a brighter polish, and rusts less quickly. Steel contains more carbon than wrought iron, but less than cast ; and all these niceties of gradation may be included between the limits of 0-25 and 2-0 per cent, of carbon. No steel worthy of the name can be made from any except good iron ; the Oregrund iron from Sweden is the best, made with charcoal fuel ; the best English is from Ulverstone. Steel Manufacture. Different processes are adopted for causing the proper quantity of carbon to combine with the iron. In England the most customary method is ce- mentation, conducted in the appara- tus described under CEMENTING FURNACE. Here carbon is made to combine with pure malleable iron. The bottom of each trough of the furnace is covered 2 inches deep with powdered charcoal, sometimes combined with salt or a little ashes and salt. Bars of malleable iron are laid on this bed parallel, and a little way apart ; then another layer of powdered mixture ; then another set of bars ; and so on, till the trough is nearly filled, no two bars being allowed to touch. The whole is covered with charcoal, sand, and fire-tiles, to keep in the heat and exclude the air. All apertures being now closed, a fierceheat is maintained for many days, more for shear steel than for spring steel, and still more for edge-tool steel, until the char- coal has been driven into the very substance of the bars of iron. Choice kinds of steel require a double cementation or converting. By drawing out bars occasionally through the testing holes, the work- man can see how the process goes on. The bars which have been con- verted are in the state called blistered steel, whiter than iron, granular in- stead of fibrous in texture, and covered with blisters. It may be forged into rough articles at once ; but for finer purposes it requires the process of tilting, to close up fissures and cavities. The blistered steel is broken into pieces 1 8 inches or so in length; half-a-do/en of these are bound together into a fagot ; the fagot is heated to a welding heat, and the tilt hammer is made to give it a torrent of blows, which weld the pieces of the fagot together, and convert the whole into a square bar of smooth dense steel. In this state it is called shear steel, and the process is often called shear- ing. A vast number of useful and ornamental articles are made from shear steel. Cast steel is still finer in quality than shear steel, and re- quires for its production a heat greater, perhaps, than any other known in manufactures. It is made from blistered steel, without the intermediate stage of shear. The crucibles are filled with this steel, broken into fragments, and then exposed to the intense temperature of a wind-furnace, which the cruci- bles are expressly intended to sup- port. {See CRUCIBLE; WIND FURNACE.) Each furnace is just large enough to contain two cruci- bles and the requsite amount of fuel. The charge for each crucible is about 301bs. of blistered steel, with a little manganese, and sometimes a little charcoal. The steel is melted in about four hours, and preparations are then made for pouring it out into ingot moulds, which are of vari- ous sizes, some large enough for about a 30 Ib. ingot, some for 40 Ibs., 60 Ibs., or more. Each mould is made of cast-iron, in two parts hinged together; and a 30 Ib. charge STE 363 STE will till a mould 2 inches square by 2 feet long. All being ready, the men put on hempen aprons and leggings, soak them in water to resist the heat, open a trap-door in the floor of the casting-house, and remove the cover from the crucible, which is just beneath the trap. With a pair of long tongs a man grasps the crucible and draws it up, exposed to a fearful heat the while. He and an assistant pour out the white, dazzling, flashing molten steel from the crucible into the mould, the in- terior of which is temporarily coated with carbon, to prevent the iron from being burned by the intense heat ; the steel sparkles and scintillates like a brilliant firework. As the steel soon solidifies, the mould is opened, and the ingot removed from it red-hot. The ingot of cast-steel thus prepared resembles a bar of tilted steel in so far as it is ready for the further processes of forging, roll- ing, &c. ; but as the metal is denser and harder than tilted steel, more care is required in the operations. Steel Manufacture, New Pro- cesses. The above description relates to the usual mode of mak- ing steel in England, as practised for a long series of years ; but it now becomes necessary to mention that vast changes are taking place, promising great manufacturing ad- vantages in the future. It is now believed that the most expeditious and economical mode of making steel would be to draw out carbon from iron which contains too much, instead of driving carbon into iron which contains too little. Many modes of following this new system are now adopted, mostly by so heating the better kinds of cast-iron in furnaces as to drive off the excess of carbon. Krupp's celebrated steel, made at his great works at Essen, in Prussia, is thus made : Carefully- selected iron, after the smelting, is puddled without refining, in presence of slag or cinder, and brought to the state of puddled steel ; this is re- melted in crucibles, and poured out into ingot moulds as cast -steel. Krupp has cast one single mass of steel weighing 50 tons a weight never yet equalled by steel manu- facturers. A very important plan for converting iron into steel is de- scribed under BESSEMER STEEL. Cheno?* steel is made by incorpo- rating a peculiai kind of iron with any substances rich in carbon, such as charcoal, resin, wood tar, or fat. Musket's steel is produced by fusing malleable iron with carbonaceous matter in crucibles, the proportions being regulated according to the kind of steel to be made, very much like the Indian wootz method of making steel. Vickers's steel is made by combining iron scrap, ground charcoal, and black oxide of manganese in certain proportions. Homogeneous metal has a little car- bon, so combined as to give it an intermediate quality between mal- leable iron and cast-steel. Riepe's steel is one of many kinds produced on the Continent by puddling in a reverberatory furnace, the making of steel being herein but a modification of the making of iron. Uchatius* steel is made by granulating molten pig-iron in cold water, and fusing the granulated metal with pul- verised spathic ore in an ordinaiy cast-steel furnace. A method called the Siemens-Martin's plan of pro- ducing steel is now (1868) attract- ing much attention. A process more recent than any of the above is Heaton's, depending on the in- troduction of certain chemical salts into the furnace. The whole trade of steel manufacture is, in truth, in a transition state, the forerunner ap- parently of highly valuable results. Steel Pens. The prodigious number of steel pens now made in England, chiefly at Birmingham, and in various cities on the Conti- nent, is among the most remarkable things in recent trade. The cheap- STE 364 STE ness is such that persons have no inducement to economise. When a writer can obtain a gross of pens for a shilling or less, he is tempted to take up a new one without wait- ing to see whether the old one is really worn out. The beginning of the steel pen was the arming of the nibs of quill pens with bits of steel, to make them more durable. Horn, bone, ivory, tortoiseshell, glass, and other substances have been tried, as harder materials than quill. Gold pens were introduced, having the nibs studded with little bits of diamond, ruby, rhodium, pal- ladium, iridium, and other kinds of hard gems and metals. Springs were attached to the back of some of these pens to impart elasticity. All such inventions, however, were necessarily too costly for the general public ; and manufacturers bent their attention steadily to the pro- duction of pens from thin sheet-steel. Barrel pens, into which a handle could be inserted ; pens with a nib like an inverted spoon ; pens with a diagonal slit ; pens with singular bends and necks to give them elas- ticity all were tried ; and the num- ber of patents taken out concerning them was enormous. The most use- ful and economical form (that with which we are all familiar) was ar- rived at after many patient trials. In making the usual steel pens, steel is rolled in sheets of a particular thick- ness, cut into broad strips, heated and annealed, scoured, and again rolled. Each strip is cut up into blanks by means of a cutting-out press, the length of the blank being in the direction of the fibre. One or more holes are stamped in each blank as well as the name of the maker, &c. Each blank, still a flat piece of steel, is then stamped up into the usual convexity and con- cavity. The nibs are ground by fric- tion upon an emery-wheel ; the slits are made by chisel-stampers of pecu- liar shape. Various processes of heating, annealing, and scouring in- tervene between the other opera- tions. The colours, mostly brown, but sometimes bluish, are produced by exposing the pens to heat in a rotatory cylinder, and removing them when a particular degree of oxidation is attained. Mr. Timmins's statistics of the steel-pen manufac- ture at Birmingham comprise some curious items. Mr. Perry paid 5.?. per pen to the first person he em- ployed, and for many years paid his workmen at the rate of $s. per dozen. It was considered a great reduction when a card of nine pens was sold for 5.?. There are now 2,500 operatives engaged in the manufacture in Bir- mingham. They make 100,000 gross of steel pens per week ; using 10 tons of high-class sheet-steel for the purpose. The selling value to the trade ranges from \\d. to is. per gross for the usual kinds of pen, and yd. to I2S. per gross for barrel pens, omitting specimens of very special kind. So wonderful have been the advances made, that pens on which twelve distinct processes have been required are sold wholesale at the rate of a penny a hundred ! One manufacturer has more than 500 marks or stamps, for various buyers who require their own names or de- vices on the pens ; another reckons his annual produce at 150 million pens. Steel Trade. It is not possible to determine the extent of the steel manufacture and trade in England, because the firms engaged therein are not called upon by any law to send in returns of quantities, values. &c. The extent of the export, how- ever, after supplying home de- mands, is approximately known. In 1867 we exported cutlery and surgical instruments to the value of ^"480,000 ; anvils, vices, saws, files, edge-tools, &c., ^490,000; un- wrought steel, in sheets, bars, rods, &c., 32,000 tons, valued at ^1,100,000 (about ^34 per ton, one STE 3<>5 STE kind with another). So far back as 1853 there were 50,000 tons of iron converted into steel, mostly at Sheffield ; but the quantity is vastly larger now, owing to the rapid advance in the use of Bessemer and other varieties of low-priced steel. About the time of the International Exhibition of 1862, there was a calculation that Sheffield possessed 205 converting furnaces, producing 80,000 tons of blistered steel annu- ally; and 2,437 casting furnaces, producing 52,000 tons of cast-steel. Coach-spring steel has been set down at a usual price of about ^20 per ton, bar steel ^35, and cast- steel /45 ; but this was before the cheapening process here adverted to. Steelyard is an instrument for weighing, different from the ordinary balance or pair of scales in many ways. As usually made, there is the short arm of a lever to receive the article which is to be weighed ; a known weight is made to slide along the longer arm of the same lever until the two arms are in hori- zontal equilibrium. It is thus known what is the weight of the substance by observing the position of the counterweight on the graduated long arm. A ring or hook attached to the fulcrum enables the instrument to be either held in the hand or hung upon a fixed support. Some steelyards have an index-hand in addition, to indicate the weight more exactly. Steelyards of a more complex kind have two fulcra, placed at different distances from the point to which the article to be weighed is attached, and having their in- dexes and suspending hooks on opposite sides of the lever; one end is used for measuring smaller weights, the other end larger. Many bent-lever balances act on the princi- ple of the steelyard. The Danish steelyard has the weight fixed at one extremity of the lever, with a mov- able fulcrum. The spring Q? pocket steelyard is one of the varieties of spring balance. Merchants of the Steelyard were German traders who Avere permitted by Edward IV. to have a commercial establishment in London. Their depot or warehouse, called the Steelyard, was on the spot where the Thames frontage of the Cannon Street Railway Station now stands. Steering- Apparatus. The helm or rudder of a ship is too well known to need description ; but very im- proved forms are now coming into use. The great iron-clad Hercules affords one among many examples of the use of improved steering ap- paratus, which gives superior ma- noeuvring power to the vessel. Not- withstanding the advantages of the balanced rudder, it is apt sometimes to miss stays, a defect which leads many commanders to prefer the ordi- nary rudder, in spite of the facilities in the former for quickness of turn- ing. A compromise between the two systems has been introduced in the Hercules. The balanced rudder is itself jointed and hinged upon the line of pivot ; and by a combination of double cylinders and bolt plates, one part of the rudder can be locked fast as a stern-post, the other part working from its hinges as an ordi- nary rudder. Or, if needed for par- ticular exigencies, both parts may be locked firmly together; and these modifications can be effected simply by the insertion or withdrawal of a couple of hand pegs. Stencilling: 'is a sort of midway process between printing and deco- rative painting, a cheap substitute "or both. A pattern is drawn upon i thin plate of metal, pasteboard, or any other convenient material, and Derforations cut through in confor- nity to it. This, which constitutes a stencil-plate, is laid upon the ubstance to be painted ; a brush, dipped in colour, is passed to and fro over it ; and a pattern becomes tainted according to the parts which STE 366 STE are not covered by the plate. Walls 9f rooms are coloured in a cheap and rapid way by this process, in lieu of paper-hanging; and devices of vari- ous kinds, in connection with many of the manufacturing arts, are pro- duced by this process of stencilling upon wood, plaster, paper, woven fabrics, and other kinds of ground- work. Stereoscope, being for purposes chiefly of fine-art amusement, calls for notice here simply as a modern item in the manufactures of Bir- mingham, where large numbers of them are made. The optical coales- cence of two foci is very beautiful ; but when the calculations and mea- surements are once made, the shap- ing and adjustment of the pieces of glass and wood become merely workshop processes, not very special in their character. Stereotype. When printing is effected from the types themselves, the latter cannot be used for any other work until the whole of the printing is finished ; when there is to be a second edition of the book, the compositor's work must be done anew. To economise time and money in this matter, stereotyping has been invented. A cast is taken from the page of type, the printing is done from this cast, and the type can at once be distributed. At first the types themselves were cemented together into a compact whole ; but the much superior plan of stereo- typing was eventually preferred, after numerous experiments by William Ged, Dr. Tilloch, and Earl Stan- hope. In the usual mode, the page of type, when corrected to the ut- most degree, is rubbed over with a little oil, or else with plumbago. It is surrounded with a brass frame, and placed in a casting-box, where liquid plaster of Paris is poured over it, with such precautions as to fill every minute line, not only in the type, but in any engraved block that may form part of the page. Re- moved from the mould, the type may be distributed, while the plaster mould is ready for further opera- tions. Dried at a temperature of 200 Fahr., it is placed face down- ward on a floating plate, and this at the bottom of the dipping-pan, already heated to 400 Fahr. ; a cover with four openings closes the pan. The pan is immersed in a vessel of molten stereotype metal (nearly the same in composition as type metal) ; the metal fills it through the openings, and thus, with a multi- tude of precautionary arrangements, a cast is taken from the plaster mould. The plate (which, for book- work, is generally the size of two octavo pages) is finished by turning, planing, backing, &c., and is then ready to be printed from. Some of these plates are afterwards bent, to adjust them for cylinder-printing. A mode of stereotyping without a plas- ter cast was invented by Carez in 1791. The page of type, face down- wards, was allowed to fall upon a layer of molten lead, which thence became a matrix or mould of the type. This matrix was in its turn allowed to fall on a layer of type metal, whereby a stereotype plate was produced. This method has not been found to answer well. Firmin Didot has invented a plan of making the matrix by heavy pressure of the type on pure soft lead, and thus ob- taining a stereotype from this lead by cliche, or stamping on a hot but partially-solidified layer of type metal. A more recent plan is to sub- stitute paper for the plaster. Sheets of unsized tissue paper are worked down upon the page of type with a short stiff brush until the paper is driven into every minute crevice and corner of the type ; a layer of starch or flour-paste being interposed between some of the sheets of paper. Dried upon a hot iron plate, and screwed down tight, the paper soon becomes a hard mould fit for casting, stereo- type metal being poured upon it in- STE 367 STO stead of upon a plaster mould. This method has been found particularly useful for printing by cylinder ma- chines, on account of the facility with which the papier-mache* could be made to conform to the curvature of the cylinder. The plan is now much adopted in newspaper work, several stereotype casts from the same mould being used in the same machine at one time. Electrotype casts are also now made ; the stereo- type plate virtually consisting of a deposit of copper instead of a layer of type metal cooled down from the melting point. Stereotyping 1 Machine is the name given to an apparatus recently (1868) invented in America. Each type is so guided as to leave its in- dented impress upon a plastic sur- face ; and then type metal being poured over the surface, a stereotype plate is produced. The motive power to work the machine is supplied by electricity; but the hand of the operator must determine which let- ter is successively selected for the impress ; this is done by pressing down the keys of a sort of piano- forte key-board, as in some of the type-composing machines. The idea is an old one; and nothing but a long course of trial will show whe- ther this mode of realising it will prove successful. Hitherto the chief difficulty has been, in all such con- trivances, to bring down the parti- cular type upon the exact spot where the letter is to be impressed a diffi- culty that must necessarily increase where the number of varieties is considerable, seeing that the whole must occupy a considerable space. One way tried has been to dispose the letters closely together in a circle, and bring those on the outside down ob- liquely. It will always (so far as past attempts have shown) be diffi- cult to shift either the types or the plate sideways through any con- siderable distance at each successive impression. Sterling-. (See STANDARD, STERLING.) Still. This is the usual name of the principal apparatus with which the distiller carries on his trade. The problem is, how best to separate the water vapour from the spirit vapour, with the least waste either of spirit or of fuel. As the State derives an enormous revenue from British spi- rits, the Excise are very stringent in the supervision of distilleries ; but as they have more than once changed the mode of measuring or estimat- ing the spirit for duty, they afford an excuse to the distiller to invent new forms of still, so as to produce more spirit for a given amount of duty. The system, for instance, may be such as to render very large stills more profitable to work than those of smaller size. There are some stills at work that will produce 3,000 gallons of spirit per hour. In Scotland a kind called Coffey's still is mostly in use for grain whiskey ; Stein's for malt whiskey; and the " small still ?> for malt whiskey of special quality. ^See DISTILLING ; GIN; WHISKEY.) Stocking-s. Stockings, or hose, were made of cloth in this country until about the time of Henry VIII., when knitted-work began to be im- ported from other countries. The more elastic nature of the new fabric soon led to its general adoption, until, in the reign of Elizabeth, knit worsted stockings were extensively worn. The use of silk was naturally confined almost to the wealthy ; while cotton stockings were but little known till the last century. Arising out of various causes, the worsted- stocking trade centred itself chiefly in Leicester, that of silk in Derby, and that of cotton in Nottingham and the neighbouiing districts. The stockingers or framework knitters were incorporated into a guild, which [as in some other cases) obstructed :he growth of trade quite as much as t fostered the infancy. Successive STO 368 STO inventors made improvements on the frame, so as to be able to pro- duce ribbed stockings and open- worked mittens ; but the plain worsted or cotton stocking has always been the characteristic type of knit-work. The apparatus itself is noticed under FRAMEWORK KNIT- TING ; while the larger development of the trade under the factory sys- tem is treated in HOSIERY MANU- FACTURE. Stone for building is usually called freestone, probably because it yields freely to the action of the saw and chisel, which the harder granites do not ; while, on the other hand, it is not so soft and friable as to crumble away quickly. The two chief classes are limestone and sand- stone, each separable into many different kinds. A softer kind, mar- ble, is largely used for more delicate purposes ; while very hard granite is invaluable in great engineering operations. The chief kinds of stone are described under such head- ings as GRANITE, LIMESTONE, MARBLE, SANDSTONE. The work- ing operations are treated under BLASTING; MASONRY; QUARRY, QUARRYING; STONE WORKING, &c. Stone, Artificial. Hard cement is, in effect, artificial stone, and so are all kinds of concrete ; but the name is usually confined to blocks of composition, capable of being used in that shape as substitutes for large squared stones. Ransome's artijicial stone is one such kind. It consists of sand, gravel, pebbles, fragments of limestone or granite, or, indeed, of almost any stony sub- stances, ground and sifted very fine, as the solid ingredients. The liquid vehicle is made by dissolving flint in a solution of caustic soda at high temperature and pressure. The solids are mixed with this liquid to a pasty consistence, and cast into any kind of hollow receptacle, whether a regularly-shaped mould or not. After slow drying, the composition is steeped in a solution of chloride oi calcium ; a chemical reaction forms insoluble silicate of lime, which is retained, and soluble chloride of sodium, which is easily got rid of. The result is an artificial stone, frag- ments of real stone cemented by silicate of lime ; a kind of flint-glue impervious to moisture ; it resists the atmosphere well, and is very hard and strong. Ransome's composition is moulded into paving stones, filters, scythe stones, and grindstones. By selecting finer or specially-coloured fragments to be mixed with the so- lution, capitals,columns, balustrades, mouldings, cornices, chimney-pieces, floorings, steps, and other kinds of ornamental stone-work are produced. Orsi's artijicial lava is made of 3 parts stone or gravel, 2 parts pounded chalk, I part tar, v -th part wax. The solid ingredients are added to hot melted tar, and the mixture is poured into moulds. Blocks, pipes, tubes, troughs, hol- low vessels, and other articles are made of this substance. Metallic lava is a mixture of 2 parts ground flint, 3 broken marble, I resin, and small quantities of wax and colour- ing matter (to imitate sandstone, red granite, &c.). This is chiefly used for tesselated pavements. The pieces are made on a flat iron plate, and are inch to I inch thick, backed up to any required thickness with plain brown lava. The mode of casting and joining the sepa- rate coloured pieces or tiles de- pends on their shapes, and on the mutual arrangement of the several colours. For the beton used as a substitute for blocks of stone in hydraulic engineering, see CON- CRETE. Stone, Decay of. Some kinds of stone have a tendency to decay or disintegrate much more rapidly than others, and in consequence are much less fitted for building pur- poses. Great disappointment in. STO 3 this matter has been felt in refer- ence to the stone used in the two Houses of Parliament. Abundant precautions, it was believed, had been taken to make a good selec- tion. A scientific commission was appointed to visit the principal quar- ries in the kingdom ; while Professor Daniell and Professor Wheatstone were employed to try the collected specimens of stone by various che- mical and mechanical tests. The investigations were confined to lime- stones and sandstones, but embraced a great variety of those two classes. Having ascertained the kinds of stone employed in several old build- ings, the age and condition were compared, and inferences drawn as to the merits of different quarries. Cathedrals, churches, abbeys, cas- tles, manor-houses, bridges were ex- amined to this end, and a consider- able body of information obtained, showing how greatly the varieties of stone differ in durability ; some having a tendency to disintegrate throughout their whole substance, some only at the surface, by rain, air, smoke, and corroding fumes from factories. The tests applied by the commissioners were remarkably complete. Specimens obtained from each quarry were accompanied with full particulars concerning the com- position and colour of the stone, the weight per cubic foot, the thickness of the workable bed, the size of block that could be procured, the price at the quarry, the mode and cost of carriage to London, total cost when worked up into masonry, and examples of its use in existing buildings ; and then, in cubes of 2 inches each way, every piece was subjected to nearly a dozen different kinds of test, chemical and mecha- nical. The result of these lengthened inquiries was, that the commissioners selected Boisover magnesian lime- stone, from a quarry in Derbyshire, as possessing a greater combina- tion of good qualities than any >9 STO other. Nevertheless, this selected stone is now found to be decaying. The beautiful Palace of Westmin- ster is displaying old age, even in its youth. A parliamentary committee inquired into the facts of the decay. It then transpired that the Boisover quarry did not contain sufficient available stone for the purpose, and that the deficiency had been obtained, during a long course of years, from quarries in various neighbourhoods. The palace is, in fact, a jumble of stones from dif- ferent localities and of different qualities, varying greatly in the power of resisting decay. Not only so, but it was found that in the Boisover quarry itself the lower beds were not so good as the upper, a fact apparently not known to the commissioners. Some of the stones at the palace actually began to de- cay only nine years after being put up, while others near them are still quite sound. The result of this un- fortunate experience is, that the causes of the decay of stone are more numerous even than had been supposed. How far decaying stone can be arrested in its decay is no- ticed in the next article. Stone, Preservation of. This is sought to be effected by causing the stone to absorb some chemical liquid which shall either change the texture to a certain depth, or at least act as a protecting varnish. One plan, by Mr. Szerelmey, consists in making the stone absorb a certain silicate solution, and then giving it a coating of asphaltum varnish ; the silicate (it is claimed) hardens the stone, while the varnish protects the silicate from moisture. Mr. Ran- some has a plan by which the stone is made to absorb, first a solution of silicate of soda, and then one of chloride of calcium. According to the theory, a silicate of lime is formed by double decomposition of these solutions, and driven into the pores of the stone to a depth varying with B B STO 3/0 STO the time of exposure. Mr. Hibble brings forward a plan for protecting stone by means of a composition of ground lime, turpentine, linseed oil, silicate of lead, and burnt copperas, and applying it as a kind of white paint. Mr. Davies has proposed a mixture of sulphur and linseed oil ; Messrs. Barffand Sullivan a mode of treatment with alumina, carbonate of zinc, and silicate of potash ; Mr. Hardwicke a mixture of potash- alum, fish oil, and linseed oil ; Mr. Quarm an application of simple oil alone ; Mr. Bernays a coating of silico-fluoric acid, washed, if the stone be hard, with solution of am- monia or potash ; Messrs. Rust and Mossop a coating of solution of caustic barytes, washed with fluo- silicic acid. Baron Gros has (tem- porarily only, it is admitted) pro- tected the stone of the Pantheon at Paris by coating it with a composi- tion of 10 parts wax, 30 oil, and i litharge, heated to 212. Mr. Spiller, of Woolwich Arsenal, pro- poses a solution of superphosphate of lime, with a subsequent applica- tion of ammonia in the case of magnesian limestone. Mr. Crookes suggests a composition of fuller's earth with dilute solution of hydro- fluoric acid. The above list might be largely added to. Some of the methods have been tried on the stone of the Houses of Parliament, but their merits can only be fully tested by time ; at present the symp- toms are not very promising. An examination of the actual condition of the stone on the exterior of the building was made in 1868 by Mr. Abel, Chemical Superintendent of the Royal Laboratory at Woolwich. He has reported unfavourably of the result. Mr. Szerelmey's mode of treatment was in some respects more effective than the others, but it left much to be desired. Stoneware. It is not easy to establish a real distinction between pottery, earthenware, brown ware, and stoneware ; but many of the products of the Lambeth potteries are well known under the last-named designation. Some of them are made from a yellowish-brown clay found at Deptford. Some, harder in kind, are made of calcined and ground flint mixed with pipe-clay. Occasionally the upper part of a brown jar is a deeper brown than the rest; this is produced by dipping it in a mixture of red ochre and liquid clay. Some of the enormous ves- sels now made of such ware require very slow baking, and much care also in the glazing. Another kind, called delft or delph, so named from the Dutch town in which it was first made, consists of a kind of marl, generally of a reddish or yellowish colour, and glazed in a somewhat peculiar way. Stone "Working 1 . When a block of any of the usual kinds of build- ing stone, such as limestone or sand- stone, has been brought in a rough form from a quarry, it goes through many mechanical processes to fit it for use. The same is nearly the case for marble and for granite, with modi- fications due to the delicacy of the former and the hardness of the lat- ter. The hand processes are chiefly conducted with the saw and chisel. The saw is an iron blade, blunt at the edge. It does not really cut the stone, but is the means of applying small particles of sharp sand, which act like the teeth of a fine saw. The sawing of stone by hand in a mason's yard is familiar to every one ; the to-and-fro motion of the blade, kept constantly wetted by sand and water. The hand-pick chips off pro- tuberances ; the chisel and mallet work down the surface to a rough level ; while sand and emery enable two surfaces to grind and polish each other. The machine processes are far more interesting. In sawing a block into slabs, several saws are fixed parallel in a frame, at dis- tances apart equal to the thickness STO 37i STO of the slabs : one series of move- ments, governed by steam power, saws all the slabs simultaneously. In Dean Forest, pavement slabs are cut twenty or thirty at a time, by fixing a number of cutters on a large revolvingdisc or cylinder; 250 square feet of pavement, if inches thick, can be cut by one of these machines in ten hours. By another machine a series of chisel cutters follow each other along the same groove, being fixed to a frame travelling along a miniature railway. Small circular cutters, ranged parallel on an axis, are employed to cut up slabs into slips and fillets of various widths. Circular pieces, even cylinders and tubes, are cut by the aid of hollow cylindrical tools, and of cutters of various kinds made to rotate. The shaping of mouldings is effected by grinding rather than cutting ; iron patterns, having the proper cuiva- tures given them, are made to rotate rapidly ; the slab of marble is caused to pass slowly under them, and is ground down by the pressure of the iron, aided by moistened sand. To grind large slabs, a flat iron plate is used ; both receive a kind of spiral motion, and the iron grinds away the stone or marble. Smaller pieces are ground by pressing them down upon a horizontal revolving cast-iron disc. The polishing is only a finer kind of grinding.- Stop of an organ is a rather in- appropriate name for a set of pipes all yielding one kind, register, or timbre of sound. Each stop has a set of pipes, governed by one parti- cular knob or draw-stop. The re- lation which these stops bear to the other parts of the instrument is described under ORGAN, CHURCH. Stourbridg-e Clay is very largely used in making crucibles, melting- pots, retorts, fire-bricks, hearth tiles, and the like, owing tp its great power of resisting heat. Only one district in England yields it. The real Stourbridge clay is so limited in ex- tent that a circle of two miles dia- meter would include the whole of it. At a depth vaiying from 3 to 180 yards, it has been dug for fire-brick and crucible purposes for at least three centuries, below a layer of thick coals ; and the clay itself is in a seam varying from 6 to 40 inches in thick- ness. Some of the glass pots now made of this clay are so large as to weigh 30 cwt. each. The pots last from two weeks to nine months each, according as they are employed for melting plate, crown, sheet, bottle, or flint glass. About 12,000 tons of the best pot-clay are worked up yearly, and 100,000 tons of all the different qualities. Stove. Referring to FIRE PLACE for a notice of open stoves, we treat here of those which are closed in by doors and covers. A stone jar con- taining smouldering wood or peat, and a brazier containing smouldering charcoal, were close stoves of a certain kind ; but we here speak of real stoves of iron, closed in for the sake of obtaining as much heat as possible from a given quantity of fuel. There are many kinds. ( I .) The Dutch stove, much used in work- shops, is an upright cylinder of sheet- iron, having one door a little above the middle, another door near the bottom, a top that can be either opened or closed, a closed bottom, three iron legs to stand upon, and a flue-hole at the side opposite to the doors. Between the level of the two doors is a grating of iron bars to form a fire-place. The upper door opens to admit the fuel ; the lower door to admit fresh air and to re- move the ashes ; the cover to admit saucepans, &c., to be placed on the top of the stove ; while the flue-hole serves as a connection with an iron- pipe chimney. Almost all the heat- producing power of the fuel is here made available. (2.) The American stove is square in build, and has a double casing, so arranged that there shall be air in the space between the STO 372 STR two. The central part is an oven for baking, while the heat from the fire surrounds this oven on top, bottom, and all sides except one. (3.) The Russian Stove. In the north of Europe a stove is used square in form, with a number of horizontal partitions. The fire is kindled at the bottom ; the heated air and smoke are compelled to pass in a zigzag path over and around all the partitions ; these partitions being formed of glazed tiles, and the whole of the stove as much as possible made of brick or tile, the heat is absorbed by these substances, and is radiated slowly, but during a great length of time, into the room. The fuel is very economically used, and the fire-place is so arranged that no smoke can enter the room ; never- theless there is a kind of stifling want of ventilation in most rooms so heated. (4. ) The Swedish stove differs from the Russian chiefly in having certain parts of the interior heated sufficiently for an oven or a boiler. (5.) Pedestal Stove. We may give this name to many varieties of close stove used in shops and halls in which there are ascending and de- scending flues, partitioned off by flat or curved surfaces of iron. The heated air and smoke have a longer distance to travel than in ordinary stoves ; they impart warmth to a rather large surface of iron ; and this metal retains a considerable store of heat from a compai-atively small Siantity of fuel. (6.) Arnolds Stove. r. Arnott devised a stove which regulates its own supply of air in a highly ingenious way, so as to burn the fuel very slowly, and yet obtain all the heating power out of it. It is a sheet-iron box, with a vertical partition nearly all the way up the middle. Near the bottom of one compartment are the fire-box, ash- pit, doors, and air-valve ; while near the top of the other compartment is the chimney flue. The valve is so small that only a little air can enter at once, and therefore the fuel burns slowly ; but the heated air circulates round and round from one compart- ment to the other, and the heat is gradually given off from the warmed surfaces. One filling of a fire-box holding only 6 Ibs. of anthracite has been known to last twenty - four hours, and to warm a good-sized library during an entire winter's day and night. There are certain minor appendages, any one or 'more of which may be used such as a bent mercurial tube so placed as to close the air-valve more and more accord- ing as less and less air is needed. Like most other close stoves, how- ever, the Arnott gives rather an un- pleasant closeness to the air of a room. Strass is the name of one particu- lar kind of flint glass, so highly refractive and lustrous as to be used in making artificial or imitative gems. Rock crystal is often used instead of sand, and a large percentage of oxide of lead. If perfectly pure, the materials produce a wonderfully close imitation of the diamond ; and if certain metallic oxides are added, the ruby, garnet, emerald, topaz, amethyst, sapphire, &c. Small quantities of borax and arsenic are sometimes added to the rock crystal, oxide of lead, and carbonate of pot- ash. The material for these imi- tative gems is usually called paste. The use of Foil (which see) greatly increases the brilliancy of the imi- tation. Birmingham is the chief seat of the artificial gem trade in England ; but Switzerland is the real head-quarters. Straw Paper is now very largely used ; but its adoption has been somewhat checked recently by the surprising advance in the use of esparto or Spanish grass. (See ESPARTO.) Numerous patents have been obtained for working up straw into paper; the process is always difficult and expensive ; and only a few of the methods have been really STR 373 STR profitable. The conversion of the straw into pulp involves many opera- tions of cutting, boiling, bleaching, draining, steaming, pulping, &c. ; each manufacturer preferring his own patented method. In most cases a portion of rag is mixed with the straw to lessen the brittleness. As an interesting exemplification of the use of straw-paper, it may be mentioned that the catalogue of the International Exhibition of 1862 was printed on paper made of a mixture of maize straw with rag ; the French edition, straw and cotton rag ; the German edition, straw and linen rag; and the English edition all three. The mode of treating the pulp when once made is nearly as described in PAPER MAKING. Straw-plait Manufacture. The very pretty results obtained by plaiting straws into a textile fabric are really one example of weaving. True, there is nothing so regular as the "long threads" and "short threads "of cloth; but still the whole substance is made up by the inter- lacing of individual strips. Grass, reeds, rushes, canes, broad fibres, or strips of almost any kind, can be treated in a somewhat similar way ; and therefore straw plait is the type of a somewhat extensive class. The processes are as follow : ( I .) Sorting the Straws. The corn stalk of wheat, rye, oats, barley, maize, &c., would all be available ; but those of wheat are most suitable. The Tuscan straw, from Leghorn and its neighbour- hood, is the finest and best of all ; and this is the chief cause of the favour in which Leghorn hats and bonnets have long been held. Not only must the kind be selected, but individual straws are examined and sorted according to their length, colours, and thickness. (2.) Splitting. Some straws are plaited whole, being merely pressed flat to facilitate the working. Others are split into four, six, or eight strips. This split- ting is effected in a curious way. A wire, having four, six, or eight sharp edges, is thrust up the hollow of the straw so dexterously as to effect the required splitting, the strips being equal in width and smooth of edge. These slips, when softened in water, can be plaited as easily as whole straws. (3.) Plaiting. The straws, as many of them as are to make one width of plait, are fastened at one end, and rapidly plaited one over another diagonally, the nimble fin- gers of the workpeople turning them over from right to left and from left to right. The kinds of plait are indefinitely numerous, depending on the kind of straw, on its thick- ness, on its being whole or split, on the number of straws plaited together, and on the kind of pat- tern produced by the mode of plait- ing. In the straw-plait district of Bedfordshire and Herts there are regular markets held at Luton, Dun- stable, and St. Alban's, at which country villagers bring for sale the plait which they have made at their own homes, the purchasers being the straw hat and bonnet manufac- turers. (4.) Making-up. It is by nee- dlework that the plaits are made up into hats and bonnets, by blocking that the proper shape is given, and by sulphuring (exposing to the fumes of sulphur) to bleach the straw to any required degree. The plaits or nar- row ribbons of straw are made at the village homes in the district above named; but the making-up of the hats and bonnets partakes more of factory operations. The plaits vary so extremely in quality that they have been known to be as high as four guineas, and as low as twopence per score of 20 yards. A few years ago there was an estimate that 70,000 persons were employed at this trade in England, producing 240 million yards of plait annually; but the con- dition of this branch of industry is very seriously influenced by the pre- vailing fashions of the day. The style of women's head-dress in 1868, STR 374 STR when bonnets almost disappeared altogether, was a means of producing severe distress in the Dunstable and Luton district. It may here be men- tioned, that when the Duke of Edin- burgh was in Australia in the winter of 1867-8, he had a straw-plait hat presented to him of peculiar charac- ter not straw, indeed, but cabbage tree, a material much employed for light summer hats in that hot region. The grass of the fronds is cut, scalded, the fibre split, and the cen- tre part of the fibres worked up into plaits of various widths and degrees of fineness. The spiral arrange- ment of the plaits to form a hat be- gins at the centre of the crown, and is extended outward over the body and brim ; after which the hat is trimmed, dressed, blocked, and finished. The hat made for the royal Prince was so full of plaiting and stitching that it contained 200 yards of plait and 68,000 stitches ; it took nearly two months in making. Stream Tin; Stream Works. (See MINING; TIN.) Strength of Materials. Great attention is paid by manufacturers and engineers, not merely to the strength of materials in their crude form, but to the changes which occur in the strength during the several mechanical processes applied to them. One substance may, in its general texture, be crystalline, an- other granular, a third laminar, a fourth fibrous, and so on; and each kind of texture has its own particu- lar characteristics both of strength and weakness. This texture must be humoured by the workman, in fashioning the substance into varied forms ; he hammers, or rolls, or draws, or welds, c., according to the nature of his materials. Many materials, too, especially wood, are stronger in one direction than in others ; and these relative tenden- cies must be well attended to in all constructional works. Especially is it necessary at all times to discrimi- nate between a crushing and a stretching a rupture of material by crushing the particles too closely together, and a rupture by tearing them asunder. There are, in fact, four modes of effecting a rupture ; the compression and the tension just adverted to, and flexure and torsion. There are in this way not only four modes of fracture, but, arising out of the same fundamental conditions, four kinds of strength and four of elasticity. Elaborate tables have been drawn up, corrected from time to time as new experiments are made, on the relative strength of a large number of materials employed in the arts. As the word strength is vague in meaning unless we define the kind of strength, the tabulations relate to hardness, elasticity, tena- city, stiffness, compressibility, trans- verse strain, and many other quali- ties. Thus, hemp is one of the most tenacious of materials ; slate among the stiffest. Derby sandstone is one of the weakest, red porphyry the strongest, of all stones. Various kinds of timber increase in their standard of strength from one ex- treme to another; but it does not follow that the transverse strengths observe the same law, seeing that the fibrous kind differ more than the dense or compact kind in the re- lation between the longitudinal and the transverse strength. Cast-iron will bear the enormous crushing force of 50 tons per square inch. In aU good carpentry and masonry, the strength of the material employed is taken as a guide in the planning of struts, stays, columns, piers, girders, and other constructional parts ; for the stability of the whole structure de- pends, not on the quantity of mate- rial employed, but on the distribu- tion in relation to the strength of each kind. The researches of Fair- bairn, Rennie, Hodgkinson, Barlow, Tredgold, Telford, Moseley, &c., have led to the collection of a mass of important facts on these subjects. STR 375 SUB Strontium is one of the less known metals, so far as concerns its use in the arts. It is very light, only 2\ times the weight of water ; ductile, malleable, pale yellow, a little harder than lead, and burns with a crimson flame when heated in the air. It is obtained by che- mical processes from a mineral con- sisting chiefly of carbonate of stron- tium. Not only does the metal itself give forth a crimson flame when heated, but some of the salts give a brilliant purple-red colour to the flame of a spirit lamp, and to burning substances with which they are mixed. The red Bengal fire of the pyrotechnist is made of a mixture of nitrate of strontium, chlo- rate of potash, sulphur, and sul- phide of potash, producing a mag- nificent red colour when burned. Strop. A razor strop belongs to the same class of tools as the hone, whetstone, oilstone, and grindstone. A cutting tool has to be brought to a keen edge, and this is effected by grinding away the steel by the action of some substance harder than the steel itself. Strop paste appears like a soft ointment ; but if it is at all worthy of its purpose, it con tains minute grains of emery or some other mineral very much harder than steel. The theory of sharpening, by whatever process effected, involves many more curious and scientific considerations than is generally suspected ; it was dis- cussed more largely by the late Mr. Holtzapffel, the eminent tool and machine-tool maker, than by any other writer. Stucco. (For various matters relating to stucco and its uses see CEMENT, MORTAR, PLASTER- ING, &c.) Submarine Boats. What little need be said concerning the attempts to navigate vessels wholly under water will be found under TOR- PEDO. Submarine Telegraph. Afte many experiments to test the power of an electric current to pass through water, a wire was immersed in the Solent, between the Isle of Wight and the main-land, in 1847, and telegraphic messages transmitted to and fro. This was the virtual com- mencement of a system which has now become of vast importance. Cables, consisting of conducting wires embedded in a non-conducting envelope of gutta percha or india- rubber, were submerged from Dover to Calais in 1850, fromHolyhead to Ireland in 1851, from England to Holland in 1853, from Italy to Corsica in 1854, from Turkey to the Crimea in 1855, from Weymouth to the Channel Islands in 1857, from Italy to Sicily in 1858, from Suez to Aden in 1859, from Aden to India in 1860, and so on. But the most interesting enterprises of this kind are those in which a tele- graphic cable is submerged to a profound depth in a broad ocean, crossing from one continent to another. The Atlantic Telegraph is the most notable example of this kind. After discovering that a pla- teau or shelf extending along the bed of the Atlantic nearly from Ireland to America would form a convenient resting-place for such a cable, Mr. Cyrus Field and other energetic men formed a company in 1855, obtained capital, ordered a cable to be made in 1856, and tried to submerge it in 1857. Disasters occurred, and it was not till 1858 that the submersion really took place along the whole distance from Ireland to Newfoundland. The cable worked well for about a month, but then failed, and has never since been of any use. Commercial and other difficulties prevented anything further being done from 1859 till 1864. During 1864-$ a new cable was fabricated, and in the summer of the last-named year an attempt was made to submerge it ; but this failed, owing to breakages, until SUB 376 SUG 1,200 miles of it were left lying useless at the bottom of the ocean. In 1866, two cables having failed, a third was made ; this was laid suc- cessfully from Ireland to Newfound- land, and the broken cable of 1865 was raised and restored. Before the close of the year both cables were working. The cables used for these purposes are, in fact, small ropes, lit- tle more than an inch in thickness. In the centre or heart are seven cop- per wires, together forming the con- ductor, and well connected with each other by a composition of melted tar and gutta percha. Outside this is the insulator, consisting of several layers of gutta percha, alternating with other layers of the cement just mentioned. Outside the insulator is a coating of jute yarn steeped in tanning liquor to make it more durable. Outside the jute are ten stout iron wires, coiled round like the strands of a rope, and each one previously covered with a layer of tarred Manilla yarn. Thus was produced a telegraphic cable IYQ- inches diameter, weighing i^ tons per mile, having 400 Ibs. of gutta percha outside 300 Ibs. of copper wire per mile, and able to bear a breaking strain of 7f tons. The construction of such a cable com- prises many beautiful processes. To make the conductor of seven copper wires, the central wire is drawn off from a drum through a hole in a horizontal table ; the drum revolves on a vertical axis, and has near its circumference six wheels, each revolving on its own horizontal axis, and each rilled with copper wire ; by this arrangement, as fast as the central copper wire is drawn from the drum, all the other six wires are twisted closely around it To make the insulator around the conductor, gutta percha is brought to the state of a soft putty, and forced into a cylindrical form by pressure through a tube ; the copper conductor has already been placed in the centre of the tube ; and it thus results that the conductor emerges from the tube nicely coated with a smooth cylindrical layer of gutta percha. The layer being thin, the cord is passed through this pro- cess twice more, to give a sufficient thickness of gutta percha. To coat the cord with jute, the cord is wound on drums, and the drums mounted on vertical axles ; unwind- ing again from the drums," the cord passes upwards through a hole in a horizontal table, being bound round as it travels with moistened jute, supplied by revolving bobbins. Lastly, to put on the external enve- lope of stout iron wires, a revolving table is provided at its circumference with ten revolving bobbins ; this twofold revolution causes the wires to pass to the central cord, and there to encircle it as a compact coil. The difficulties of submersion in the ocean are great, and many of the most important submarine cables have been broken, if not altogether lost, during the operation. Even- tually, as the several obstacles are overcome, there will probably be cables submerged in most of the more important seas and oceans. The instruments for transmitting and receiving messages are refine- ments on those noticed under ELECTRIC TELEGRAPH. The achievements in submarine telegra- phy are truly marvellous. As an example, on Feb. I, 1868, a mes- sage was sent from Ireland to Cali- fornia, through 2,000 miles of ocean and sea cable and 5,000 miles of land wire ; it reached California in two minutes, and got there on Jan. 3ist, California time ! It thus out- stripped the sun so far as concerns longitude and clock-time. This wonderful rapidity depended on special arrangements, planned to show what can be done if urgency demands. Sug-ar. This invaluable substance, the type of nearly all sweetening SUG 377 SUG ingredients, is the juice of plants, or rather, a product of such juice ; that is, the sugar with which we are most familiar is so produced, but the chemist recognises many kinds ob- tained from other sources. The sugar-cane produces the most abun- dant and the best-known supply from the sap or juice. Beet-root is another valuable source. The ma- ple, palm, maize, and numerous other plants may be added to the list. Every kind of ripe fruit con- tains sugar, to which, indeed, its sweetness is due. Even celery, as- paragus, and onions may be made sugar-producing; and so may manna. As to honey and liquorice, their sweet- ness is well known. Like many other of our important supplies for every-day wants, cane-sugar was known in the East long before Europe had risen to any high degree of civil- isation. It was too costly, when all the expenses of freight had been defrayed, to be used at first for other than medicinal purposes ; and it was not until comparatively modern times that it came into general use not, indeed, until tea, coffee, and chocolate had become familiar beve- rages. Sugrar Candy is a peculiar kind of crystallised sugar. It is of two colours white, bleached by clari- fying; and brown, or unbleached. The syrup of sugar is put into a copper vessel, with strings stretched across it at certain intervals. As the syrup cools and evaporates, it slowly crystallises on and around the strings, and on the sides of the vessel. This is continued several days, until all the syrup that will crystallise has become sugar-candy : the remainder is poured off as treacle. Sugar Cane. The sugar-cane is the chief source of sugar supply ; and wherever this plant grows well and readily, there is its natural home. It will grow in nearly all the hot countries in the world ; but the regions which mostly supply England are the West Indies, East Indies, Brazil, and Egypt. In this as in many other cases, the countries most fertile in the plant itself are most at the mercy of rude and ineffective mechanical appliances ; so that the best modes of extracting the juice from the canes are seldom adopted in the sugar countries themselves. The canes are there simply squeezed between two wooden rollers, or are bruised with a pestle and mortar by cattle power ; much of the juice is left in the cane to waste by the imper- fection of these processes ; and that which is obtained is subject to still further waste by the mode of boiling it over an open fire. The sugar- cane grows to a height of 6 to 15 feet, with a stem i^ to 2 inches diameter. It takes twelve to sixteen months to arrive at maturity. "When it is ripe for cutting, the stem is of a straw- yellow colour, and the juice or sap has become sweet. The plants are cut down near the ground, tied up in bundles, and carried to the crush- ing-mill. All the arrangements are made for operating on the juice as soon as the canes are cut, otherwise it would ferment and spoil. The fresh juice contains about 20 per cent, of its weight in good sugar ; but the planter seldom gets more than 7 or 8 per cent., owing to the hasty and clumsy nature of the pro- cesses. In the East Indies, the juice, called goor, is sold to persons who granulate it into various kinds of sugar known by the names of kKur, ninsphool, doloo, gurpattah, do- barah, andjeraunee. The processes are so imperfect, that the produce in Bengal is usually not more than 2,600 Ibs. of solid sugar from an acre of plants only two-thirds of that which can be obtained by better methods. Sug-ar Manufacture. The fol- lowing are the chief processes by which sugar is produced in esta- blishments provided with well-made European machinery of the most SUG 378 SUG recentkinds : ( I . ) Milling or squeez- ing. It is always by pressure that the juice is expelled from the canes ; and the mill employed for this pur- pose is a very powerful machine, with iron rollers of great weight. The canes are carried forward by a self-feeding apparatus, split, slightly pressed by one pair of roll- ers, and heavily pressed by another pair. The juice, which runs down in a continuous stream into a vessel prepared to receive it, is opaque, and of a. yellowish green. About 60 Ibs. of it are obtained from loolbs. of cane by the very effi- cient apparatus now employed ; but the state of the atmosphere some- what affects this ratio. Another estimate is, I hogshead of sugar from 1,500 gallons of juice, the pro- duce of 13 tons of cane. The firms of Pontifex and Wood, Mirlees and Tait, and Neilson, make sugar-mills of great size and power, with rollers 6 feet long and 30 inches diameter, capable of pressing out 3,000 gal- lons of juice per hour. Even this magnitude has been exceeded in a sugar-mill with rollers 7 feet long, 33 inches diameter, weighing 10 tons with the shaft and gudgeons, and pressing out 4,000 gallons per hour. Some of the mills have three, four, and even five rollers. Mr. Bessemer has introduced a form of mill in which the canes are for a longer time under pressure than by the rollers, leading to the more com- plete extraction ot the juice. (2.) Boiling. The juice contains a large amount of water, and of impurities which must be removed before gra- nulated sugar can be obtained ; not more than 20 per cent, is real sugar, and much less than this of sugar that can be crystallised. By rapid boiling in vessels heated by high- pressure steam, the watei is driven off without affecting the general qualities of the juices ; but by slow and long-continued boiling, certain changes are produced which are not conducive to excellence of results. (3.) Clarifying. Most of the water having been driven off, the juice goes into the clarifier. This is. a very large copper vessel, heated by steam pipes coiled round near the bottom. Salts of lead, sulphurous acid, and other substances have been employed to clarify ; and there are frequent novelties introduced into this part of the manufacture. The result is, that sediment and scum are removed, and the juice flows as syrup into a re- ceiving vessel. (4.) Concentrating. By one stage after another, the syrup changes its form into granulated sugar. The concreter is a machine which has a series of shallow iron trays, so placed that the syrup can flow in a continuous stream from one to another ; all the trays are highly heated, and the syrup boils as it travels along. Hence it passes into a very long copper cylinder, where, being rotated six times a minute over heat, and being supplied with a kind of hot-blast within, the syrup be- comes thicker, or more glutinous and concreted, every minute. The apparatus produces about 2 Ibs. of concreted sugar from i gallon of syrup. The concreted sugar passes into a vacuum-pan, where it is exposed to a rapid boiling at about 150 Fahr. This could not be done under ordinary arrangements, be- cause sugar requires a temperature of 230 Fahr. to boil ; but by cre- ating a partial vacuum in the pan, through the action of an air-pump, the desired result is brought about. Great advantage is thus derived ; for the overheating of the sugar is averted, while at the same time that kind of concentration is insured which can only result from boiling. Some vacuum -pans are made as large as 8 feet diameter, boiling 80 tons of sugar in twenty-four hours. (5 . ) Drying. The modern apparatus for granulating and drying the sugar is a great improvement on that for- merlv in use. The mass flows into SUG 379 SUG a centrifugal machine which rotates 1,000 times a minute. It consists of crystals of sugar entangled in a mass of molasses ; the crystals are retained in the inner case of the machine, while the molasses is driven through a series of small holes into an outer case. This is soon accom- plished, owing to the rapid action of the machine. The sugar is fine enough to be used for ordinary purposes, without further processes. The molasses, subject to further treatment, yields coarsei sugar, and finally the well-known sweetener, treacle. Mr. Cola's estimates, being for machinery suitable for introduc- tion into India, do not relate to matters applicable only to England. Thus the sugar factory supposed by him is not for making refined loaf- sugar,but common crystallised or gra- nulated sugar, and is intended to be established on the sugar estate itself. One cane-crushing mill, large and strong ; three clarifiers, with copper pipes for steam-heating ; one con- creter, with trays, revolving cylinder, self-acting fan, and pump ; a copper vacuum-pan, with all the appliances; three centrifugal machines ; and all the necessary steam-engines, boilers, tanks, cisterns, pipes, tubes, and mill- gearing, are set down at ^5,200. A great sum this, and only likely to be profitably employed on a large estate. Such a factory would work only during certain seasons of the year, but then it would work day and night. Sugar Refining 1 . A sugar re- finery, as the term is usually under- stood in England, receives the sugar already brought to a granulated state, and really as sweet as it is ever likely to be. The object in view is to re- move all colour from it, and (usually) to bring it to the form of a compact crystalline mass, with which we are familiar under the name of loaf or lump sugar. Processes of a peculiar character are required for this pur- pose. Not only, however, are re- fined loaves of sugar made, but also crystal sugar and crushed sugar, which are nearly white without being agglomerated into masses. At Bristol (the head-quarters of sugar- refining) there is one establishment which has cost ^250,000 to build and stock, and in which 500 hands are employed. The chief operations in a sugar-refinery are as follows: (l.) Dissolving. The sugar, emp- tied out from the hogsheads, cases, or bags, is put into melting -pans with a certain quantity of water, with a little b^lood and lime-water added. (2.) Bag Filtering. Some of the impurities, coagulated by the blood and lime-water, are removed by straining; and then the sweet liquor passes into bag filters, which separate some further impurities. (3.) Charcoal Filtering. The filtered liquor passes then through a thick layer of pounded charcoal, which so far removes the colour that the liquor becomes nearly as colourless and clear as water. (4.) Boiling. The liquor is boiled down to the consistency of syrup in some such a vacuum-pan as that described undei SUGAR MA- NUFACTURE. The syrup, quite lising, is poured into moulds. The moulds are made either of porous clay, or of iron enamelled or var- nished within. The syrup is stirred up in the moulds for a time with a spatula, and is then left quietly to granulate or crystallise, which takes from two to three weeks. It comes out of the mould as the well-known 'white, htmp, or loaf sugar. A further modification of the process produces a still finer kind, called clayed sugar. Other forms are crushed sugar and sugar crystals. Th portion of the syrup which will not crystallise is allowed to trickle out of the small end of the mould; it constitutes treacle. (See also BEET-ROOT SUGAR.) Sugar Trade. This trade is now of very great magnitude. There is (5.) Loaf Moulding. lite ready for crystal- SUG 380 SUL difficulty in even guessing how much sugar is made in the whole world ; but the quantity that comes to Eng- land is exactly known, owing to the care taken by the Customs that every pound of it shall pay duty. The quantities imported during 1867 were as follows : Unrefined sugar, 10,550,000 cwt. ; refined sugar and sugar-candy, 830,000 cwt. ; molasses, 250,000 cwt. Of these enormous quantities, the West Indies sent us about 4,000,000 cwt. ; Cuba and Porto Rico, 3,300,000 cwt.; and Brazil 1,200,000; the remainder being the produce of various other countries. The computed value of this sugar was somewhat over ^"13,000,000 ; while the import duty derived from it amounted to ,5,600,000. There is often more than 3,000,000 cwt. of sugar at one time in the bonded warehouses of the United Kingdom, kept in bond until the owners choose to pay the duty. Sugar of Lead is the name given by the older chemists to what is now called acetate of lead. It is made by boiling litharge or oxide of lead in acetic acid, and then concentrating and crystallising the newly-formed compound. Sugar of lead is much used in calico-printing. Being very poisonous, care is neces- sary in its employment. Sulphur. This remarkable sub- stance, yellow, brittle, inodorous, and tasteless, is seldom found in a native state, being nearly always combined with other bodies. It is, when pure, about twice as dense as water. It melts at about 230 Fahr. ; from that point it becomes browner and more viscid up to 390; then becomes again more and more limpid up to 750, when it boils. If the vapour be collected and cooled in a vessel, it constitutes flowers of sulphur. If, at about 400, it be poured in a thin stream into cold water, it becomes a soft, brown, spongy, elastic mass, with which or impressions of seals may be ;. Sulphur is found in various casts made. degrees of purity in volcanic districts, such as that of Etna, whence much of our supply is obtained. The best kind, when dug up, is put into a sort of caldron or oven of peculiar shape, and set on fire all openings being as much as possible stopped up. In seven or eight hours the sulphur melts out of the ore ; a tap- hole is opened, and the sulphur flows into large wooden brick-shaped moulds. The earthy residue in these ovens, and new ore of poor quality, are then treated to obtain a further supply of sulphur ; they are mixed, melted in close pots or crucibles ; distilled ; the sulphur vapour is con- densed into a liquid, and the liquid into a solid. Much of the sulphur imported requires to be refined. This is done in one of two ways : (i), Distilling, and recovering it in the form of flowers ^ of sulphur ; or, (2), melting, and pouring into wooden cylindrical moulds. There are, in fact, several different forms in which this substance is prepared for use in the arts comprising roll sul- phur, refined sulphur, black sulphur, milk of sulphur, and flowers of sul- phur. When the sulphur owners of Italy and Sicily, finding the demand for sulphur largely increased (chiefly through its employment in making sulphuric acid), raised the price, chemists sought about for another source whence to obtain it ; they soon found what they wanted in iron pyrites (sulphuret of iron). When the foreign dealers felt the effects of this unexpected rivalry, they lowered the price again, but too late to prevent the establish- ment of a regular manufacture of sulphur from pyrites. The trade, however, settled down by degrees into a definite position ; sulphur from pyrites being sufficiently good for making into sulphuric acid, while volcanic or Sicilian sulphur is re- served for making gunpowder, and SUL SUL for certain other purposes. The iron pyrites is obtained from Wick- low, Cornwall, and several foreign countries. The obtaining of sul- phur from this mineral is described under SULPHURIC ACID. This most valuable acid is a compound of sul- phur and oxygen. Another com- pound of the same elements, sul- phurous acid, is a colourless suffo- cating gas, used in some kinds of bleaching, and in other manufactur- ing processes. A third kind is hyposulphurous acid, of some im- portance in photography. Sulphu- retted hydrogen, easily obtained, and speedily evolved from decaying substances, is a colourless gas with a very offensive odour, indirectly useful in many chemical manufac- tures, and an active agent in some of the mineral waters. With car- bon sulphur forms the bisulphide of carbon, a transparent, colourless, inflammable liquid, possessing valu- able optical qualities, useful as a solvent of india-rubber, and in many other ways. With chlorine sulphur forms chloride of sulphur, a deep yellow liquid which acts as a solvent in the same way as the bisulphide. The combinations of sulphur with the metals are mostly sulphur ets or sulphides, and constitute many valu- able ores. There are several other compounds of sulphur useful in the arts, but the above are the principal. The quantity of sulphur exported from Sicily varies from 100,000 to 150,000 tons annually. The im- ports into England in 1867 were I,i66,ooocwt. Sulphuric Acid, so largely used in chemical manufactures, is one of the compounds of sulphur and oxy- gen. The technical name, oil of vitriol, is derived from the fact that this acid was first obtained by distil- lation from green vitriol, or sulphate of copper ; the liquid is, however, not an oil in any sense, and the old name is being gradually abandoned. So long as the acid was prepared from green vitriol, it was rather costly ; but a cheaper method was devised about 1 700, of obtaining it by combustion and other processes applied to a mixture of sulphur and nitre, To prevent corrosion, glass vessels were used ; but these being both costly and fragile, leaden chambers were afterwards substi- tuted in some of the processes ; this was about the year 1750, and a great cheapening of the product re- sulted. By degrees it became cus- tomary to use lead chambers of enormous size, even so much as 200 feet in length. The manufacture in such chambers is briefly as follows : Outside one end of the chamber is an oven for burning sulphur and nitre; nitric acid and sulphurous acid vapours are produced ; these gases are admitted into the chamber, together with one or more jets of steam. Chemical action ensues, which leads to the formation of liquid sulphuric acid, while the gases containing nitrogen escape ; but many subsidiary processes are ne- cessary to make the separation com- plete. The air of the chamber sup- plies the oxygen which converts gaseous sulphurous acid into liquid sulphuric acid. Some of the cham- bers have as much as 30,000 cubic feet capacity each ; and the temperature maintained is somewhere about 130 or 140. At a proper stage the liquid acid is drawn from the cham- bers through lead pipes into a leaden boiler, where it is concentrated to a density of about 17 (water = i). If further concentrated it would cor- rode the lead ; and therefore the acid is transferred to stills made of glass or of platinum, in which it is con- centrated to the strength of ordinary commercial sulphuric acid, or oil of vitriol. Platinum is so expensive a metal that some of the sulphuric acid stills made of it have been worth .3,000 each. When the acid is obtained from iron pyrites, instead of from a mixture of sulphur and SUL 382 SWE nitre, the pyrites is washed at the stamping-mill, and spread in layers on plates of iron heated to redness ; or else the sulphur of the burning pyrites is made to serve as fuel for a new charge. Sulphurous acid gas, rising from the burniijg pyrites, passes into leaden chambers, where it is converted into sulphuric acid in some such way as that already de- scribed. This acid is very largely employed in making soda, and in many other branches of chemical manufacture. When combined with various metallic, alkaline, and earthy oxides, it forms the group of sub- stances known as sulphates, the uses of which in the arts are almost end- less. Sulphate of alumina and pot- ash is alum; of baryta, heavy- spar; of copper, Hue vitriol ; of iron, green vitriol or copperas ; of lime, gypsum; of magnesia, Epsom salts ; of soda, Glauber's salt; of zinc, white vitriol. Sulphuring 1 , or Sulphur ation, is a mode of bleaching by the aid of sulphur. Silk, woollens, straw plait, sponge, and a large number of other substances may be bleached or whitened by this agent. There are two methods practised. (i.) The articles are hung up in a damp state on strings across a closed chamber; in the corners of the room are placed open vessels con- taining sulphur ; the sulphur is ig- nited, the workmen retire, the door is closed, and all openings also closed except one to admit a little air, and another for the escape of the gas. This gas is sulphurous acid, which exerts a bleaching ac- tion. (2.) The whitening effect of the sulphur is developed in a liquid instead of a gaseous form by im- mersing the article in a solution of sulphurous acid, sulphate of soda, or sulphate of potash. Sumach, is a plant of which the roots and wood are very valuable in tanning ; and of some species the leaves and the seeds are also rich in dyeing and tanning ingredients. It grows in all the four quarters of the globe, and is valued in most coun- tries. (See TANNING.) We imported 260,000 cwt. of this substance in 1867. Sundials. Although these time- measuring instruments are not now much used, it may be as well to ex- plain the principle on which they act. Every sundial has a style, or straight edge (usually of metal), so arranged as (when the dial is in use) to be parallel with the earth's axis; and the shadow of this edge is received on a graduated surface. The sur- face may be a plane, horizontal or vertical, or a hollow hemisphere, or a cylinder : any of these will do, pro- vided the graduation is suitable. Usually the dial is a horizontal plane. There is one line on the dial for twelve o'clock at noon, others for the forenoon hours, others for the afternoon hours. When the dial is laid down flat, in sunshine, the shadow of the style marks the hour by coinciding with one or other of the hour-lines. Owing to the ellip- ticity in the motion of the earth round the sun, sundial-time does not quite correspond with clock-time ; there is an adjustment necessary, called the equation of time, which is tabulated in most of the best almanacs. Sunn is one of the many varieties of fibre used for the same purposes as hemp, to be spun and woven into stout fabrics. It grows plentifully in various parts of India. Swage is a tool for giving shape to some kind of yielding or ductile material ; it is a model or pattern on which the material is pressed down by means of a burnisher. The mode of swaging thin sheets into teapots and other forms is noticed under BRITANNIA METAL. Sweep Washings are the ex- tracted gold and silver from the sweep- ings or refuse of the workshops in which the precious metals are em- swo 383 TAT ployed or fashioned. Every scrap is as far as possible collected and utilised. Dust from the benches and the floor ; water in which jewellers and others have washed their hands ; old melting crucibles : old aprons and waistcoats of goldbeaters all are made to give up their minute quota of gold or silver. This is effected by numerous processes of pounding, grinding, mixing, washing, &c. The prepared odds and ends are mixed with mercury and water, pressed to get rid of the water and superfluous mercury, and then the amalgam is made to give up its precious metal by the careful application of heat and acids. Sword Manufacture. This is a peculiar kind of cutlery-work, depending for its characteristics on the necessity of giving great tough- ness to the steel. Toledo swords and Damascus swords obtained in past ages a great reputation for toughness, flexibility, and keen edge. Most English ' swords are now made at Birmingham, by successive processes of casting, heating, hammering, swaging, hardening, tempering, set- ting, grinding, glazing, hiking, and proving. Sycamore. The wood of this tree (nearly allied to the fig tree) is light and porous ; but there are some purposes in the arts for which it is suited. Sympathetic Ink. (See INK.) Syringe, or what schoolboys call a squirt, is used for some few pur- poses in the arts. It is really a pump. The handle, with a piston wrapped round with soft cotton, draws the air out of the cylinder, and water is sucked up to fill the vacuum. The garden syringe is a larger kind ; the stomach-pump is a syringe ; and so were the fire-pumps that were used before the invention of the fire- engine. Syrup. This subject is sufficiently noticed under CONFECTIONERY and SUGAR. Cane-juice, concen- trated to a certain density, forms a syrup which may be shipped and ex- ported without danger of fermenting. T. Tabby. In the finishing of some varieties of silk and fine stuff goods, they are passed between rollers so engraved as to give a kind of wavy lines to the surface, producing an agreeable play of light and shade. The process is called tabbying, and is one mode of calendering. There is but little difference between tabby- ing, watering, and moire. Tabinet, as a material for window curtains, is a texture of silk and wool, comprising some of the cha- racteristics of damask and poplin. Tacks are small nails with broad thin heads, used for fastening down carpets, and for numerous other pur- poses. They are made in one or other of the modes noticed under NAILERS, NAIL MAKING. Taffeta is one of the numerous varieties of silken goods, having a fine glossy surface greatly enriched with stripes and patterns, often in gold and silver. There is also a general sense in which the name is applied to many kinds of silk goods. Talc is a silicate of magnesia, which is found in small quantities embedded in some of the harder kinds of rock. It is a very curious sub- stance, splitting easily into thin plates which have a kind of semi- metallic lustre. It is used in making boot powder, cosmetics, polish for alabaster, porcelain paste, crayons, &c. Tallow is the solid fat of animals. It can be separated into about three- fourths solid stearine and one-fourth liquid oleine ; and hence arise many of the variations of quality in can- TAM 384 TAN dies and soap. The home supply of ox-tallow (the best for these pur- poses) being quite insufficient, we import largely from Russia, Aus- tralia, and other countries. The tallow, in the living animal, is con- tained in minute cells ; it is separated from the membrane of the cells, for use in manufactures, by a pro- cess called rendering, involving the use of heat and steam. The imports of tallow into the United Kingdom in 1867 amounted to 1,100,000 cwt. Tambouring-; Tambour "Work. (See EMBROIDERY, &c.) Tammy is a thin glazed worsted cloth, much used for women's boots, and for a peculiar kind of sieve or straining-cloth. Tamping 1 , or the closing of blasting holes, is noticed under BLASTING ; MINING ; QUARRY, QUARRYING, &c. Tanning-. Under the article LEATHER most of the principal kinds have been mentioned. An account may now be given of that mode of preparing the thicker hides which comes under the name of tan- ning, (i.) Unhairing. Most of the hides come to the tanner with the hair on; and the removal of this hair is among the early processes. Green, salted, and dried are three degrees of softness which the hides present; and different degrees of soaking and scraping are required for them. Then the hides are thrown into pits, where they are steeped seve- ral days in lime and water to loosen the hairs. This done, the hide is placed upon a beam or stool, and scraped on both sides on the one with an unhairing knife, to scrape off the hair; on the other with a fleshing knife, to remove a thin layer of flesh and fat. As the lime dissolves and wastes some of the useful parts of the membrane, many other modes of softening the hair are occasionally adopted partially fermenting the hides in a smoke- house ; piling up in a heap with spent tan ; exposing them to damp, confined air; and employing various acids. (2.) Bating. The thinner hides, after unhairing, are subjected to a process called bating steeping for many days in an alkaline solu- tion, with frequent stirring and scraping. This removes the hair, and gives suppleness and softness. (3.) Slow Tanning. By slow tan- ning we mean the ordinary process, without the aid of any new expedit- ing methods. The tan-pits are ob- long cisterns sunk in the ground of the tan-yard ; and here the hides are steeped for a long time. Oak bark is the chief tanning ingredient ; but there are many others employed. The bark is reduced to powder by grind- ing in a bark-mill, and is then ex- posed to the action of water, warm or cold, until all the extractable matter is drawn out ; the liquor so prepared is called ooze. The hides are steeped in this ooze for days, weeks, or even months, according to the kind of leather to be made. The process is greatly varied in different tanneries ; but the object is the same in all to make the tannin of the ooze combine with the gelatine of the hide. ^4.) Quick Tanning. The price of good thick leather is neces- sarily high, on account of the large amount of capital lying dead during the long period (in some cases as much as fifteen months) absorbed in the ordinary tanning process. Hence many attempts have been made to devise new processes. Spilsbury's plan depends upon forcing the ooze into the pores of the hide by hydro- static pressure, instead of allowing it simply to work its way in slowly. Drake's plan consists in sewing up the hides into a kind of bag, filling this bag with ooze, and compelling the ooze to pass through to the out- side. HerapatWs plan involves the use of machinery; the hides are passed repeatedly between rollers, to assist in forcing the ooze into the pores. Squire's plan makes use of TAN 385 TAN rotary action. The hides and the ooze are placed in a large horizontal wooden cylinder or drum, which ro- tates six or eight times a minute ; ridges inside the cylinder increase the agitation to which the hides are exposed, and facilitate the entrance of the ooze into the pores ; the ooze in this process is used in a hot state. Bordier's plan consists in employing certain metallic and earthy sub- stances, instead of oak burk or other vegetable bodies ; he does not con- vert the hide into actual leather, but so changes it that (in the opinion, at least, of the inventor) it will not pu- trefy or decompose. Although every patentee of course claims special merit for his own invention, it is generally found that these methods of quick tanning produce leather more hard and brittle than the old. (5.) Striking. When the hides are sufficiently tanned, they are taken out of the tan-pit, washed, drained, and dried in airy lofts. At intervals during the drying they are struck; that is, they are scraped with a pecu- liarly-shaped knife, so as to get rid of a kind of bloom which forms on the surface. (6.) Hardening. Very little more remains to be done to prepare the leather (which the hides have now become) for market. It is condensed or hardened, either by being beaten with a kind of tilt hammer, or by rolling under a heavy weight. (7.) Splitting. Sometimes thick hides and skins are split into thinner by a beautiful process. A knife-edge works against a rotating cylinder, around which the hide passes. The knife has a recipro- cating or lateral movement to and fro ; and it is so nicely adjusted that the hide is split by it into two layers or sheets with wonderful equability in thickness. Sometimes the split- ting is done when the tanning is finished, sometimes when only half finished. The grain or outer half of such a split skin is used in the best kinds of work, the flesh or inner half for inferior purposes. The spent oak bark, when it has done its work in the tan -yard, is dried and used for making hotbeds for the gardener, and as manure by the farmer ; or else it is compressed into cakes, and used as fuel. Much of the cheap fuel sold in London under the name of turf consists of this spent tan. Tanning* Drugs. The chief article used in tanning is oak bark. The trees are stripped during the warm spring months, when the sap is abundant; a coppice tree about twelve years old yielding the richest bark for the tannin it contains. About 5 Ibs. are needed for tanning i Ib. of leather. Sumach, used in tanning some of the thinner kinds, is the powdered leaves and young branches of the wild olive and the ivy-leaved sumach. Divi-divi, used in making a porous brown leather, is the pod of a South American plant called Ccesalpinia coriaria. Valonia, useful in making heavy, imperviable leather, is the acorn-cup of a species of oak growing in the Le- vant. Catechu, which tans a large quantity of leather in proportion to the quantity used, and somewhat quickly, is a powdery substance ob- tained by steeping the bark, wood, and leaves of the Acacia catechu. Cutch and Terra Japonica are varie- ties of the catechu class. Myrobalan, much used in India for tanning, is the bark of the fruit of certain trees growing in the East. Mimosa, useful in preparing some kinds of leather, is the bark of a kind of wattle growing in Australia and New Zealand sometimes imported as a fluid ex- tract of the bark. Cork-tree bark, very rich in tanning, is the inner bark of the tree which, in its outer bark, yields the well-known sub- stance, cork. Larch bark, used in tan- ining the inferior sheep-skin leather called basil, is a cheap substitute for oak bark. Willow bark is used in making Russia leather, and also cer- tain kinds of kid and lamb-skin lea- c c TAP 386 TAR ther employed in the glove manufac- ture. Nut galls are rich in tannin ; but this tannin has a tendency to change into gallic acid, and can on that account only be used with cau- tion by the tanner. Tapestry. This kind of textile work, so great a favourite among noble ladies in bygone times, is a sort of medium between weaving and embroidery, partaking some- what of both. The threads may be of silk, of wool, of silk and wool com- bined, and may or may not be com- bined with gold and silver threads ; but there must always be differences of colour in the threads, to repro- duce the design. Whether em- ployed for carpets, furniture, covers, curtains, or wall decoration, the word tapestry applies rather to the mode of producing than to the appli- cation. There are three kinds, (i.) Hand Tapestry, The earliest tapestry was undoubtedly worked by hand. Woollen threads, by the patient application of the needle, were worked into a net of meshes, and a coloured pattern worked in at the same time ; or else a silk pattern was worked into or upon a woollen ground. (2.) Haut-lisse Tapestry. This name is given to a method in which warp threads are arranged ver- tically, and weft interlaced with them by the tapestry- workers. The warp threads, unwinding from an upper roller, descend to the level of the worker, and are wound on a lower roller when finished. The cartoon or pattern is placed behind the warp, through the threads of which it can be seen, and the pattern is copied on the front of the threads with some kind of paint or chalk. The pattern is then woiked in at the same time as the fabiic itself is made, for a kind of needle forms both the weft and the pattern. It is very slow work, necessitating the use of a number of needles . with an equal number of different kinds and colours of thread ; and the worker has every minute to see that the pattern is being correctly followed. (3.) Basse -lisse Tapestry. This name is given when the warp threads are arranged horizontally. The worker sits instead of standing, as in the former case. The cartoon or pattern is placed under the warp threads, through which it can be seen. The weft is thrown in with a small apparatus called by the French and Flemish tapestry- weavers a flute, somewhat midway in action between a needle and a shuttle. There are treadles to de- press some of the threads to form a land of shed through which the flute may pass ; the process thus makes a nearer approach to weaving than to embroidery. The most cele- brated tapestry in the world is that which is called the Bayeux tapestry, 214 feet long by 20 inches high ; there is embroidered on it a series of pictures representing the invasion and conquest of England by Wil- liam, and it is supposed to have been worked under the superinten- dence of his queen, Matilda. Speci- mens of old tapestry are open to the public at South Kensington Museum and at Hampton Court Palace. Tapioca undergoes very little of what can be called manufacture. It is the meal or flour of the cassava- plant. While in a moist state, the cassava is heated and dried on hot plates ; the grains swell and burst, and coalesce into small, irregular lumps. Tapioca swells up into a jelly-like mass when steeped in boiling water. Tar is the residue obtained in the manufacture of turpentine; or rather, the natural sap of the fir tree yields the latter, while the roots yield the former. As rudely conducted in the Baltic provinces, tar-making pro- ceeds as follows : Roots, logs, and billets of fir are stacked up closely in a cavity in the ground, or in the side of a hill, and completely covered in with well-rammed turf. Being TAR 387 TEA then kindled, the wood yields its tar, which flows out at a hole left for the purpose. This tar is virtually a mixture of all the turpentine, sap, and juices of the wood, leaving be- hind it nothing but charred wood, or charcoal. Common tar of this land is useful for many rough pur- poses in the arts ; but the tar ob- tained during gas-making (see ANI- LINE COLOURS; COAL-TAR PRO- DUCTS ; GAS PRODUCTS) is now made to yield a surprisingly large number of valuable substances, in- cluding the beautiful magenta colour. 13,000 casks of tar were imported in 1867. Tarpaulins. These strong sheets or coverings, made of tarred canvas, or canvas coated with some other kind of preservative composition, are used in enormous number by railway companies as coverings for merchandise on goods waggons, and for luggage on passenger carriages. They are technically called sheets : the accounts concerning them are kept by a distinct department at each of the great railway depots ; and the railway clearing-house esta- blishes a rent per day to be charged for the use of every sheet belonging to one company and employed by another. Tartaric Acid exists ready formed in many kinds of fruit, to which it imparts their characteristic sharpness ; and it also exists in a large variety of roots and tubers. Tartar is a bitartrate of potash, de- posited during the fermentation of wine ; and from this tartar the acid is usually manufactured by various chemical processes. Tartaric acid is largely used by calico-printers and by lemonade-makers ; while the tartrates of lime, potash, soda, ammonia, baryta, magnesia, lead, &c., are applied to many useful pur- poses. Cream of tartar, soluble tar- tar, Brunswick green, and tartar emetic are all of them tartrates. Tawing- is the name of one kind of leather-making in which tanning, properly so called, does not take place. The gelatine of the skin is made to combine, not with tannin, but with alum and salt ; it becomes a kind of preserved membrane. This is the process employed in making most of the leather for white kid gloves. Goat, kid, sheep, and lamb skins are all tawed, to pro- duce different varieties of white lea- ther. The wool and hair are loosened and removed by some such process as that described under FELLMON- GER, and the skin brought to the state of a thin, clean membrane called pelt. Several of these pelts are put into a drum or cylinder, with alum, salt, and water ; after being rotated some time, the alum and salt combine with the gelatine. Then, after washing in clean water, fer- menting in bran and water, and drying, each pelt presents itself as a white, tough leather, but wanting in suppleness and gloss. Wheat flour and yolk of egg are dissolved in water, and the pelts are rotated in a drum with this solution ; the pelts absorb the whole of the yolk. They are steeped a short time in clear water, spread out openly, and scraped repeatedly over a blunt but smooth metal edge. This gives the final softness and elasticity to the white leather. There may be a greater number of processes for the finer than the cheaper varieties of kid (they are all dignified with this name) ; but the prevailing principle is the incorporation of alum, and then of egg yolk, with the gelatine of the pelt. So amazing is the con- sumption of eggs for this purpose that some of the large firms at Ber- mondsey (the head-quarters of the leather trade) will have 50,000 to 100,000 eggs in store at once, pre- served in lime or in salt. Tea. This valuable plant under- goes certain well-conducted pro- cesses after the leaves have been gathered. The chief gathering of TEA 388 TEL the crop takes place in the month of May. The leaves, when plucked, are put into bamboo baskets, brought into a kind of barn, and dried. This drying is effected on a kind of frying- pan over a fire-place or kiln, the leaves being kept in agitation while drying. They are then rolled by hand over a bamboo table, by which more moisture is expelled from them, and they become more or less curled up. After this, heating takes place, to expel the remaining moisture, \vith special precautions, to prevent the leaves from burning, by keeping them in constant motion while over the fire. Picking, sifting, sorting, and packing then ensue. Some kinds are dried in baskets over a charcoal fire. The above kinds are green tea. The Hack kinds are pre- pared for market in a somewhat different way ; but the Chinese are not ignorant of the art of so using Prussian blue and other substances as to convert black or inferior tea into so-called green. The imports of tea into the United Kingdom in 1867 reached the large amount of 128,000,000 Ibs. Teak, largely grown in India, is one of the most valuable kinds of timber ; being light, easily worked, strong, durable, and little attacked by insects, it is largely employed both in India and in England for ship-building of the highest class. The teak of Africa, sometimes called African oak, is another kind of wood, but somewhat similar in qua- lities. Teazle; Teazling. In the woollen-cloth manufacture, after the fulling or felting has been com- pleted, the fibres of the threads are scratched up to form a pile or nap. A plant is especially grown to sup- ply the means of doing this ; viz., the teazle. This is a kind of thistle, grown largely in Yorkshire and the neighbouring counties for the sake of the teazles or thistle-heads, which are nearly the size and shape of average strawberries. As the plant is precarious, the crop varies greatly. From 2,000 to 3,000 are needed for teazling a piece of broadcloth 40 yards long. In hand teazling, the teazles are fixed in a small wooden frame which is held by a handle ; the cloth is laid out smooth, and damped; and the teazles are worked repeatedly over the cloth in the weft and the warp directions. The fine hooks with which the teazles are covered scratch up the woolly fibres, and leave them stand- ing up as a roughish pile, which is afterwards sheared to form a smooth nap. In machine teazling the teazles are arranged on the surface of a cylinder in the gig-mill; the cloth travels in one direction, the cylinder rotates in the opposite, and the teazles perform their wonted work while the two are in contact. Many attempts have been made to substitute iron wires for teazle-heads ; but no means have yet been found for obviating a tendency in the wires to tear the cloth where inequalities occur; the teazle-points are more elastic and accommodating. (See further under WOOLLEN-CLOTH MANUFACTURE, &c.) Teeth. (See IVORY for a notice of the chief uses of teeth in the arts.) The sea-cow, sea-horse, sea-morse, and other animals besides the well- known elephant have teeth which subserve many useful purposes in manufactures. The chief compo- nent element in all teeth, varying from 50 to 90 per cent, of the whole, is phosphate of lime. Many thou- sand hundredweight are imported annually. Telegraph. The transmission of messages to distant spots by various mechanical means is briefly noticed under SIGNALS. The name sema- phore or telegraph is more usually given when the arrangements are such that long messages can be sent, and regular conversation held. These arrangements (until the in- TEL 389 TEL (reduction of the electric telegraph) mostly comprised the use of mov- able boards or arms. Dr. Hooke, nearly two centuries ago, suggested the use of boards of different shapes to represent different letters of the alphabet, hoisted in a frame that would be visible from a distance. Amontons, early in the following century, suggested a somewhat simi- lar plan for use in France. In 1793 Chappe's semaphore came into ope- ration in that country. It consisted of a cross-bar at the top of a vertical pole, and arms at the two ends of the cross-bar; letters and words were denoted by various positions of these arms. Mr. Lovell Edgeworth, father of Maria Edgeworth, devised about the same time a telegraph consisting of four poles with mov- able triangular boards at the top ; these boards were made to denote signals by giving different angular positions to the points. Late in the last century and early in the present many forms of shutter telegraph were suggested, to show signals by opening and closing shutters ar- ranged in a frame. Then there were movable radii across an open circle ; two arms of different shape hinged to the top of one pole ; two or more arms affixed at different heights to the same pole ; and various other modes of construction. The British Admiralty for many years main- tained a line of telegraph from Lon- don to Dover, and another from London to Portsmouth ; telegraph stations were maintained on elevated spots a few miles apart; and each station had a lofty pole with arms working laterally upon it. These semaphores were worked for the last time in 1847, and were superseded in 1848 by the beautiful system noticed under ELECTRIC TELEGRAPH and SUBMARINE TELEGRAPH. Telescope. This grandest of all aids to the astronomer does not come within the scope of the present volume in regard to its scientific purposes ; nor does its manufacture admit of much description, except as involving the highest class of workmanship in metal and glass. The kinds of telescope are chiefly as follows : A refracting tele- scope has an object-glass at one end and an eye-piece at the other ; the object-glass collects the rays of light into a focus, while the eye-piece adjusts them to the proper condition for entering the eye. A reflecting telescope has no object-glass : there is a large metallic mirror or speculum to col- lect and reflect the rays, and a smaller speculum to assist in con- veying them to the eye-piece. These are the main differences in tele- scopes; but there are minor diver- sities of many kinds. Thus a Gali- lean telescope is a refractor, having some such action as an opera-glass ; a Gregorian is a reflector with the eye-piece in a line with an opening in the centre of the large speculum : a Newtonian reflector has the eye- piece on one side of the tube ; a Herschelian reflector has the eye- piece at the remote end of the tube ; an equatorial is a telescope, whether refracting or reflecting, which has a clock-work movement to enable it to follow the daily motion of the hea- venly bodies ; a transit instrument is a telescope so adjusted as to keep always in the plane of the meridian ; a zenith instrument is a telescope so fixed as to point to a spot directly overhead. Although refracting tele- scopes are those with which most astronomical discoveries have been made, reflectors are those which have involved the most remarkable manipulative or manufacturing fea- tures. Three of these especially may be cited, (i.) The Hertchel tele- scope, made at Slough by Sir Wil- liam Herschel in 1789, was 40 feet long, with a reflector 4 feet in dia- meter, and a huge scaffolding to support and work it. On the first day of using it the great astronomer TEM 390 TER discovered the sixtk satellite of Sa- turn. (2.) The Rosse telescope, made by the late Earl of Rosse, at Parsonstown in Ireland, about 1850, is no less than 52 feet in length, with an exterior diameter of the tube amounting to 7 feet ; the great speculum is 6 feet diameter ; and the tube is made of wood strength- ened with iron hoops. (3.) The Melbourne telescope, made at Dub- lin by Mr. Grubb in 1868, at a cost of ^5,000. It is a reflector, 40 feet long by 4 feet diameter. The great speculum weighs 2 tons, while the weight of the whole instrument is 8 tons. The tube is quite original in its construction ; 7 feet of its length is made of boiler-plate i^ inch thick; but the rest is an open lattice-work of steel bars, twisting round spirally ; the two sets of spirals cross each other diagonally, and the bars are riveted at the points of crossing ; while the whole is stiffened by steel hoops j placed at intervals. It is believed that this construction will be more effective, as well as lighter, than a continuous close metal tube. This is the largest equatorial in the world ; the mass, ponderous as it is, moves by clock-work to obey the move- ments of the heavenly bodies ; and the balancing on opposite sides of an axis or fulcrum is almost as ex- quisite as in a small pair of scales. This magnificent instrument was made, by order of the Government of Victoria, for the Melbourne Ob- servatory in Australia. For the re- flecting mirrors of such large tele- scopes see SPECULUM. Tempering-. Sheffield steel goods depend much for their quality on tempering, or changes in hard- ness produced by changes in heat ing and cooling. Heated steel be- comes harder by plunging into cold water or oil; but it also becomes too brittle for many purposes ; and this brittleness is removed by again heating slowly and moderately. Ihe art consists in partly undoing by heating what has been done by cooling; and the degree of temper thus given is made to depend on the purpose to which the steel is to be applied. When cautiously heated to the required degree, it is again suddenly cooled, and has now ac- quired hardness without being too brittle. The workmen know by the colour straw yellow, dark yellow, brass yellow, purple yellow, light purple, dark purple, dark blue, green- ish blue when the proper degree of hardness has been obtained. The lowest temperature, 430 Fahr., gives a very pale straw yellow, and is suitable for lancets ; the highest, about 600 (blue or purple), is almost too soft for any kind of steel instru- ments ; penknives, chisels, files, shears, axes, plane -irons, table- knives, swords, gun-locks, watch- springs, fine saws, and coarse saws have their respective temperatures and colours to denote the proper temper or degree of hardness. Template, in metal- working and wood-shaping, is a pattern or guide, presenting curved and straight edges in a certain determinate arrange- ment. Its purpose is to insure cor- rectness in distance, size, and figure in various kinds of cutting, filing, piercing, &c. Tenon. The tenon and mortise, one among many kinds of joint, is noticed under CARPENTRY. Terra Cotta, or " baked clay," is midway in quality between earthen- ware and tile clay, but always has some kind of artistic finish. The ancient terra -cotta was slightly- baked clay of fine quality. The modern variety contains fine sand or calcined flint mixed with fine clay. It is sometimes pressed into form while having the consistence of clay; sometimes poured as a creamy liquid into moulds. It is used for pinnacles, capitals, and other architectural decorations, as well as for chimney-pieces, figures, vases, &c. The employment of TER 391 THE terra -cotta has much extended in recent years. Even large statues, such as many of those in the grounds of the Crystal Palace, are made in this material. Terra Japonica. (See CATECHU, which is the native name of this gum.) Textile Goods. (See COTTON, FLAX, HEMP, JUTE, SILK, SPIN- NING, WEAVING, WOOLLEN, WORSTED, &c.) Thermometer. So far as con- struction is concerned, a few words will suffice to notice the thermo- meter, the scientific applications of the instrument being out of place in this work. In an ordinary ther- mometer there is a small glass bulb, with a slender hollow glass stem rising from it. It contains mercury enough to fill the bulb and a portion of the tube. When the bulb, is subjected to a higher heat, either from the weather or from any other cause, the mercury ex- pands, and rises higher in the tube ; when the heat lessens, the mercury shrinks, and sinks lower in the tube. Marks, or graduations, either on the stem or on a plane surface adjacent to it, serve to distinguish one inten- sity of heat from another. Almost any liquid could be employed ; but mercury and spirit of wine are the best, for various reasons. Great care is necessary in making the glass tubes and bulbs, and in filling them with the mercury or spirit ; any irregularity in bore would render the graduations incorrect ; while any grease or air in the tube would in- terfere with the free rising and sink- ing of the liquid. Nearly all the common thermometers in England are made by Italians resident in the Hatton Garden and Leather Lane district, as well as many of the su- perior kinds used in scientific in- vestigations. An awkward fact in reference to English thermometers is, that our graduation is very rarely adopted on the Continent. What is called Fahrenheit 's scale divides the interval between freezing water and boiling water into 180 equal parts or degrees ; but as the freez- ing point is called 32, the boiling point becomes 212. Reaumur's scale divides the interval into 80 equal parts, and begins with o as the temperature of freezing water, wherefore that of boiling water be- comes 80. The Centigrade scale begins at o for freezing water, and rises by 100 equal degrees to boil- ing water, which is 100. This is becoming the favourite scale on the Continent, as it facilitates computa- tion to a greater degree than either of the other two. The following are approximate values of a few parallel temperatures on the three scales : Fahr. 10 20 32 40 60 80 100 150 200 212 250 300 350 - 7 o 4 IS 27 I 8 65 93 100 121 149 177 Reaum. -9 5 o 3 12 22 31 5 2 96 119 141 Thermostat is a name which the late Dr. Ure gave to an instrument for regulating the temperature of hothouses, hot baths, ventilated rooms, &c. It consists of two bars of metal soldered or riveted together, one being more readily affected by heat than the other. If the bar is quite straight at a particular tem- perature, it will become bent at any higher or lower temperature, be- cause the more susceptible of the two metals will drag the other with it. The bending of the bar is made, by some kind of leverage, to open or close a damper in a flue, and TIII 392 TIL thereby regulate the draught. Or the compound bar may be a curve, the radius of which is changed by any change of temperature. Thimble Making:. These small useful articles are generally made from sheet-metal, by the aid of a stamping-press and a die or mould. Many different dies are needed, and much care in the process, to pre- vent the metal from being cracked and broken. Thrashing-, or Threshing:. The effective steam - worked apparatus now employed as a substitute for the hand-worked flail is briefly noticed under AGRICULTURAL MA- CHINES and STEAM FARMING. Thread is in effect yarn made thicker, or at least more dense, than for weaving. All fibres that can be spun into yarn for weaving can also be spun and twisted into thread for sewing, lace-making, hosiery, &c. In factory- language, thread always means two or more yarns twisted one around another. Lace thread, which is usually very fine, consists of only two yarns ; but sewing thread comprises two or more. The thread-frame is a kind of throstle machine (see SPINNING), with spindles, flyers, and rollers. The yarns are doubled or trebled, and then twisted round each other in a direction contrary to the twist of each individual yarn ; this is the plan adopted in making cables or thick ropes, and for a similar reason to give increased strength. The thread, when made by this doubling and twisting, is tied up into hanks. According to the material of which it is made, and the purpose to which it is to be applied, it is either bleached and dyed or not. Very beautiful apparatus is then employed to wind the thread (if for sewing) upon reels or into balls. There may be from 30 to 300 yards in each reel, and from 1 6 to 600 balls to lib. The little gold-printed labels on the ends of the reels and balls have adhesive gum at the back, and are stuck on by children. The smallest and commonest of these labels are sold to the thread-makers so cheaply as one halfpenny per gross ! A very delicate and beautiful machine is employed to wind the thread on the reels, giving to the threads a re- markable parallelism of arrange- ment. We exported 6, $00,000 Ibs. of thread in 1867, after supplying home wants. Throstle. This little imple- ment, so important in textile manu- factures, is described in connection (or rather contrast) with the mule frame, under SPINNING. Ticking- is a strong linen cloth, usually woven in blue and white stripes, and used for beds, pillows, mattresses, &c. The cheaper kinds are now often made of cotton. Tiles, Draining- and Roofing-. There are wide differences in the colour and qualities of tiles, accord- ing as they are used for coarse or for ornamental purposes. We treat here of the rougher kinds, used for tiling roofs and for draining land. The clay, purer and stronger than for common bricks, is -weathered, or exposed to the weather for some time, to open the pores and sepa- rate the particles ; then mellowed, or covered with water in pits ; then tempered, or ground to the proper consistency in a pug-mill. The moulder then sets to work. Roof- ing tiles are plain tiles if quite flat, and pan-tiles if curved in surface. The moulds are simple in form ; and the moulder, with his hands kept constantly wetted, easily presses the soft yielding clay into them, aided by a few wooden tools and imple- ments. Fine coal-dust is used to prevent the clay from adhering to the moulds. One man can mould 1,200 to 1,500 in a day. After drying in the open air, the tiles are baked. A tile-kiln is something like a glass-house, having a central oven or furnace surrounded by a TIL 393 TIM conical structure, diminishing to a chimney at the top. The interior of the oven is packed with tiles, set up in a particular way ; the fires are lighted, and the baking is continued until the usual brick-red colour is produced. Draining tiles, drain- ing pipes, chimney-pots, andgarden- -bots are all made of clay differing but little in character from that em- ployed for roofing tiles ; and the processes of manufacture are nearly the same so far as concerns drain- ing tiles. For draining pipes, how- ever, a kind of mould is needed, through which the clay is forced by heavy pressure, the size and shape of the mould depending on the kind of pipe to be produced. Sometimes machines are employed to make the pipes, in the way described under BRICK MAKING, and also to make the hollow bricks now so advantageously used. In making circular chimney- pots and garden-pots, the potter's wheel comes into requisition, as described in POTTERY. Tiles, Tesselated and En- caustic, have lately been revived with success, after many ages of comparative disuse. These very often consist of a red clay or marl, with a device sunk in the upper surface, and this device filled with clay of another colour. The red marl is exposed for a time to the weathering action of the air, blunged or worked in water, sifted through fine sieves, evaporated to a certain degree of stiffness, worked up into a sort of cube, cut off into slices with a wire, backed up with a slice of clay of coarser kind, and stamped with a mould or die. The pattern thus indented is filled up with creamy clay of some rich colour; and thus, after further processes of trim- ming, sand-papering, drying, baking, and (sometimes) glazing, ornamental tiles are produced, suitable for a large number of purposes in deco- rative architecture. There are other methods practised for making orna- mental tiles in soft clay; but the above is the plan on which the chief of Messrs. Minton's beauti- ful specimens are produced. Mr. Prosser's dry process is a remark- able one. The material, a mixture of clays, after certain preparatory operations, is dried, ground to powder, and sifted as finely as pos- sible. A mould, the proper size and shape for the tile, is virtually two steel dies, an upper and a lower; the powder is thrown into this mould and subjected to intense pressure (300 or 400 tons), by which it becomes almost as hard and dense as stone. Pieces of this kind are usually, not flat tiles, but small cubes or tesserae, which may be combined to form a mosaic pave- ment oj- slab; some of them have raised or sunken devices on the upper surface. Tilting-; Tilt Hammer. In Sheffield and other steel-working towns, a tilt is the name often given to the building in which tilting is carried on by means of ztilt hammer. This hammer is a kind of helve or shingling hammer; but, by a peculiar arrangement of levers and cogs, the head of the hammer is made to fall much more rapidly, even so many as 360 strokes per minute. Such a hammer requires a very firm founda- tion and strong framework to resist the impact ; and when several of them are at work in one building, as at Sheffield, the noise is tremen- dous, and the ground all around trembles; for every hammer, weigh- ing 150 to 200 Ibs., is giving its 300 or 400 blows a minute. The purpose of tilting is noticed under STEEL, &c. Timber. There is no other dis- tinction between timber and "wood than this that timber trees com- prise the larger kinds, yielding pieces of wood wide and thick as well as long. As a general rule, all the wood employed in engineering and building is called timber. The tree* TIM 394 TIN are felled, or should be felled, at the time when the largest quantity of firm and durable wood is obtainable with- out much sap, seeing that mischief occurs from the decay of timber in cases where this precaution is neg- lected. It is of course impossible to draw a precise line of distinction between the kinds of wood used for different purposes; but the follow- ing is an approximate grouping : Elastic wood : ash, hazel, hickory, lance wood, yew. Tough wood : beech, elm, oak, walnut, lignum- mtB. Even grain : pine, lime tree, pear tree. Durable for diy carpen- try: cedar, poplar, yellow deal, sweet chestnut. Durable for wet carpentry : alder, plane tree, white cedar, &c. For ship-building : fir, larch, teak, locust wood, S^c. For machinery and mill work: maho- gany, box, crab tree, hornbeam. For turnery and Tunbridge ware : birch, alder, willow, holly, horse-chestnut, sycamore, apple tree, plum tree, Sec. For furniture: cherry tree, Amboyna, ebony, Coromandel, maple, rosewood, satin wood, tulip wood, zebra wood, partridge wood, sanders wood, olive wood, king wood, cocoa wood, cam wood, beef wood. The principal kinds of wood used for their colour- ing properties are named under DYE DRUGS. The timber grown in the United Kingdom varies from about 22 Ibs. per cubic foot (dry), up to 47 Ibs., the extremes being shown by Lombardy poplar and evergreen oak. These are about equal in density, weight, or specific gravity to one- third and three-fourths of the weight of water respectively. The uses of various kinds of wood are illustrated under such articles as CARPENTRY, CARVING, COOPERAGE, JOINERY, TURNING, VENEER, WOOD-WORK- ING MACHINES, &c. Our imports of timber in 1867 amounted to the large quantity of 3,400,000 loads. Timber, Preservation of. Varia- tions in temperature and in moisture are the chief causes of the decay of timber, leading to fungous growths, the attacks of worms and insects, and to the crumbling away of the whole substance of the wood. Where it is impossible to protect timber from variable supplies of air, heat, light, and moisture, attempts are made to enable it to bear these variations with a minimum of injury. Two such modes have been noticed under BURNETTISING and KYANISING; and others have been devised by Bethell, Payne, and other inventors. Corrosive sublimate, chloride of zinc, oil of tar, creasote, pyrolignite of iron, gas tar, and sulphate of iron are among the substances which have been used for this purpose, applied either as a kind of varnish to the wood, or as a solution in which it is to be steeped. What is called dry-rot is only one among many forms of timber decay. One of the simplest and best preservatives of wood is oil. This fact is corroborated by the healthy soundness of the tim- ber of the whale-ships, which be- comes thoroughly imbued with oil. Tin. As a metal used in the arts tin occupies a very high place, and has done so from early times. It is more easily extracted from its ores than many other metals, and com- bines with a remarkable number of other metals to produce useful alloys. When pure it is lustrous, and almost as purely white as silver. It is so malleable that it may be beaten out into sheets of tin-foil or white Dutch metal less than T^OO inch thick. It is not very ductile, unless combined with a little lead. Its density is from 7 to 1\ times that of water. The tin of commerce is never quite pure, generally contain- ing small portions of arsenic, iron, or lead. It is not much affected by the air at ordinary temperatures. The protoxide, fused with glass, forms white enamel ; the protoxide and peroxide constitute putty powder ; the chloride, with a solution of gold, produces the purple of ' Cassius ; the TIN 395 TIN bisulphide is known as mosaic gold or bronze powder ; and the sulphate is Bancroft's tin mordant. Most tin is obtained from the oxide, in the forms of stream tin, wood tin, and tinstone, which differ in the degree of richness. A fairly good quality of tinstone contains 60 to 65 per cent, of metal. Tincture. It is hardly necessary to notice tincturesin connection with the manufacturing arts ; but it is useful to know that they are pre- parations of some vegetable sub- stance, with alcohol, ether, or wine as the liquid solvent. The old al- chemists gave the name of quintes- sence to a higher and purer form of tincture ; while elixir was a tincture of thicker consistence and less trans- parent. Tin Manufacture. When tin ore has been raised from the mine, and prepared for the smelter (see MINING; ORE DRESSING), it is roasted to get rid of the sulphur and arsenic. This is done in a furnace similar in general arrangement to that described un- der REVERBERATORY FURNACE; the arsenic is collected, condensed, and sublimed in a chamber con- nected with the furnace, and consti- tutes the well-known white arsenic. The ore, when roasted, cooled, and washed, is known as block tin. This block tin is smelted in a smelting- house, if ordinary metal is to be pro- duced ; but in a blowing- house, if very line tin is to be made. The smelting-furnace is reverberatory. The ore is laid upon a hearth or sole ; the heat from a fire reverberates down upon it ; and the fumes are conveyed up a chimney 50 or 60 feet high. The ore, mixed with a little powdered coal and slaked lime, is smelted in charges of 20 to 25 cwt. ' at a time, slightly sprinkled with water. At a particular stage of the operations the fused mass is worked about with a long iron paddle, to separate the slag from the tin ; and this slag is separated into three kinds, according to the quantity of metal in it for it always contains some. When ready, the molten tin flows through an unstoppered hole in the furnace into a basin; and, when skimmed at the surface, it is laded out into rectangular moulds, which yield blocks of metal. A pro- cess of refining then goes on, to get rid of some or all of the iron, arsenic, copper, tungstates, and oxides with which the tin is more or less con- taminated. A double process is necessary for this. In the first, called liquation, the tin is melted by slow fusion, and flows into a basin; in the second, called poling, billets of green wood are placed in the molten metal, bringing up various oxides to the surface, and precipitating the heavier impurities. When the metal is separated from its accompani- ments as much as is practicable by this means, it is laded out into moulds, which form masses of 3 cwt. or so, known in commerce as block tin. All the slag and scum are smelted and refined two or three times, to yield as much as may be of the tin they contain; this pro- duces a kind of tin suitable for in- ferior purposes. The very best qua- lity obtained by the refining process is called refined tin, and is used in making Tin Plate (which see). A peculiar kind of fine metal called grain tin is procured in small grains or tears. In England, as we have said, tin is smelted in reverberatory furnaces, about one and a half tons of coal being used to every ton of tin produced, and 5 per cent, of metal is lost. The blowing-house is a place in which very pure tin is smelted in a small blast furnace, with charcoal as fuel. This is the mode often adopted in Saxony, where coal is dear and wood-char- coal cheap. The interior of the furnace is mostly of granite ; a small blowing machine sends in a blast of air through a nozzle ; and TIN 396 TIN the molten metal is refined by the poling process with billets of green wood. The loss of metal by this mode of smelting is 15 per cent. Tinning-. Besides the making of tin plate, there is a very useful practice of applying a surface of tin to manufactured articles made of some other metal. The tin has a ten- dency to prevent iron from rusting and staining. Bridle-bits, common stirrups, small nails, and tacks are made in large quantities of cast-iron, and then tinned. Cast-iron sauce- pans and large pots are coated with tin on the inside. In order to do this, the iron is made thoroughly clean, and heated ; melted grain tin is poured in, and the vessel turned and rolled about to enable the tin to touch every part; the surface is rubbed with cloth or tow to aid the process, and powdered resin is em- ployed to prevent the formation of oxide. Copper and brass vessels can in like manner be tinned. A coat- ing of tin covers all the best pins. (See PIN MANUFACTURE.) There is also a process called cold tinning, for applying a surface of tin to other metals by means of an amalgam of tin and mercury. Tin Plate. The manufacture of tin plate or tinned iron requires a remarkable degree of care, to insure a thorough adhesion of the two me- tals. In the first place, the sheet- iron must be made expressly for the purpose, of good iron well rolled ; it is, indeed, charcoal iron, for which it is worth while to pay a high price. The rolls of sheet-iron are uncoiled, spread out flat, and cut into oblong squares by means of shears. The plates are placed up- right in a pickle of dilute muriatic acid, to dissolve and remove impuri- ties. They are then (without being handled) heated in a furnace until the oxide scales off. They are cooled, beaten flat on a smooth cast- iron block, and cold-rolled between hard polished rollers. By these pro- cesses the plates are made clean, flat, smooth, and elastic. They are further exposed to the action of bran and water, and dilute sulphuric acid, both moderately warm ; they are scoured with hemp and sand, washed, and kept in clean water till wanted for use. All this exempli- fies the extreme care bestowed on the cleansing and preparation of the plates. Then ensues the coating of the sheet-iron plates with tin. Block tin and grain tin, in about equal pro- portions, are melted in a cast-iron vessel, and coated with 4 inches depth of tallow. Another vessel, containing melted tallow only, is close at hand; and in this the plates are kept immersed till wanted. They are taken out one by one, and plunged into the tin bath, to the number of 200 or 300. The grease protects the tin from the air, with- out interfering with the closeness of contact between the tin and the iron. After remaining an hour or two, the plates are taken out one by one with tongs, and transferred successively to the wash-pot, the grease-pot, and the list-pot ; in these vessels, with the aid of melted grain tin, melted tallow, and a hempen brush, the actual quantity of tin on each plate is equalised, and the adhesion to the iron made as complete as possible. The plates are finally cleansed from the grease by rubbing with warm dry bran. The utmost care is taken not to touch the surfaces with the hand from first to last, lest they should be soiled with perspiration or dirt. When finished they are packed in boxes, 100 to 225 in a box. Each box is marked with a brand, to denote the number, size, and quality of the plates ; and there are about twenty of such varieties. The boxes, when filled, weigh from 67 Ibs. to 252 Ibs. each ; and the in- dividual plates vary from I2| by g\ to i6| by 12^ inches. There is a demand nearly all over the world for English-made tin-plate, so excel- TIN 397 lent is it in quality, and so useful for manufacturing into saucepans, kettles, and other culinary articles. The tinned surface remains intact for a surprisingly long time. Tin Trade. In 1867 there were 117 tin mines in the United King- dom, yielding 13,649 tons of ore, valued at ,694,734. The tin made in England, from this and other ore, was 8,700 tons. The export of tin, in various forms, amounted to 84,000 cwt. (4,200 tons) ; but that of tin- plate (in which the weight of the tin is very small compared with that of the iron), reached the enormous amount of 1,600,000 cwt. Tobacco. Although snuff-taking has rather declined, and tobacco- chewing has not increased, the habit of smoking has extended so enor- mously that the tobacco manufac- ture has become one of consider- able importance. In many foreign countries it is a complete monopoly, while in England a very large re- venue is derived from it. Tobacco has been cultivated in Europe for a little over three centuries, but the quality of the leaf never seems quite to have equalled that grown in some parts of America and Asia. To- bacco is one of the few things which must not be cultivated in England (except as a botanical curiosity) ; an import duty of many hundred per cent, is laid on foreign tobacco ; and to keep this revenue as high as pos- sible, home-growing is prohibited. The tobacco plant is an herbaceous annual, growing to a height of 6 to 9 feet, and producing leaves vary- ing in size up to a maximum of 20 inches long. It requires good rich soil, and constant attention during growth. There is a particular degree of ripeness when the plants are best fitted to be cut, and at that time the leaves are yellowish green. They are cut down near the ground, dried in the sun, and conveyed to the curing-house. Here they are hung on poles, and exposed to the action TOB of a uniform temperature of the air for a month or more. They are then removed, and the leaves stripped from the stalks ; the leaves, slightly damp, are tied up into small bun- dles called hands. The bundles, thrown into a heap, are allowed to undergo a certain amount of fer- mentation. After this they are packed in hogsheads for shipment. Each hogshead contains from i,ooolbs. to i,2oolbs. of leaf, packed very tightly and closely in every part, and then condensed by heavy pres- sure. We imported 6 1, 000,000 Ibs. of tobacco in 1867. Tobacco Manufacture. In England the imported tobacco has to pay a very large duty before it can be taken out of bond at the docks; and there are always vast stores on hand at London, Liver- pool, Bristol, and other ports, seeing that the owner does not like to pay the duty until the last moment. The tobacco warehouses at the Lon- don Docks are among the sights of the metropolis ; they sometimes contain 20,000,000 Ibs. at one time, and stringent regulations are made by the authorities to prevent a single pound from leaving the warehouses until the duty is paid. If any of the tobacco is too much damaged to make it worth while to pay the duty, the owner abandons it, and it is burnt in the warehouse, in a kiln jocosely called the " Queen's to- bacco-pipe." When the duty is paid, and tobacco is to be removed, the hogsheads are taken partially to pieces ; the dense mass of to- bacco is exposed; the damaged portions (if any) are all cut away ; the hogshead is replaced, and the tobacco removed to the premises of the manufacturer. Here the leaves are dug out of the mass, being sprinkled with water to aid the pro- cess . Hand-work is the name given to the leaf with the stalk in it ; strip- leaf is the leaf without the stalk ; and the hand-work is usually made TOB 398 TOR into strip-leaf before the tobacco can assume the proper form. The strip- ping is effected by the dexterous use of a small instrument. The leaves, pressed together into a cake, are cut into shreds by a machine some- thing like a chaff-cutter, worked by hand, horse, water, or steam power. Variations in the kind of smoking- tobacco depend on variations in the leaf and in the processes. Returns are made from a light- coloured leaf; shag is a dark leaf, sprinkled with much water during the manufacture ; kanaster is a coarsely-cut tobacco ; Orinoco is much finer ; pig-tail is made into a kind of cord or small rope ; negro-head has a tuft -like arrangement ; Cavendish is pressed into a hard flat cake ; bird's-eye owes its name to the light-coloured bits of stalk among the leaf, &c. (See also CIGAR MANUFACTURE ; SNUFF MANUFACTURE.) Tobacco Pipes are made (in Eng- land) of a fine white clay obtained chiefly from Purbeck, in Dorsetshire. When dug up, the clay undergoes a few preparatory operations, and is then formed into large cubical masses. Small pieces, each suffi- cient for one pipe, are cut from the mass. The workman rolls out a piece, leaving a bulb at one end; he drills a hole right through it with a wire held by a wooden handle ; he places it in a copper mould, with the bulb at that end of the mould which is to form the bowl ; he closes the mould, which thereby gives form to the pipe (a temporary plug main- taining the size and shape of the interior of the bowl). Most of the lettering, ornament, &c., is given by the mould ; but others are given by small rollers and stamps. The pipes are smoothed with iron rubbers and grooved agates, dried in shallow trays, and baked in large seggars or crucibles placed in an oven. The clay is always so chosen that the pipes shall come out of the oven baked to a nearly pure white, so far as possible. A special kind of smok- ing-pipe is noticed under MEER- SCHAUM PIPES. Tombac, rather a richly-coloured metal used in the making of buttons and small ornaments, is a mixture of 75 copper and 25 arsenic. Topaz, the finest specimens of which come from Brazil, are gems varying in colour from white and yellow to blue. Yellow topaz, for purposes of jewellery, often has the tint deepened nearly to red by the application of heat. It is rarely used for any other purpose than as a gem. Torpedo is a kind of submarine vessel, floating and moving wholly under the surface of 1 he water. Most attempts at this kind of navigation have been made in connection with hostile attacks in war; but some have been advocated with more peaceful views. The idea seems to have arisen into favour soon after the successful adoption of the Diving Bell (which see). Cornelius Drobell made a boat that would move for a short time under water, by some un- recorded method of renewing the supply of air. Mr. Day made a vessel with some such intent in ! 1774, but lost his life in Plymouth while putting his disastrous scheme into operation. Mr. Bushnell, an American, applied an Archimedean screw in some way to a submarine boat in 1775; but nothing further seems to have been heard of it. Robert Fulton, one of the improvers of the steam-vessel, tried his hand at several forms of submarine boat. After many abortive attempts by numerous inventors, Mr. Delaney, another American, constructed "a submarine boat in 1859. It was shaped something like the eccentric Cigar ship ; and its interior was pro- vided with a screw propeller, iron tanks for air and water, pipes and stop -cocks, a steam-engine, and some mode (chemical or otherwise) of purifying the air ; but the modus operandi is far from clear. A sub- TOR 399 TOR marine boat, properly so called, must contain one or more men ; but a torpedo, to be used in war, is a combustible machine which, whether movable or not, may be brought under an enemy's ship, and there made to do its work of destruction. Robert Fulton and other inventors tried to combine the navigable with the explosive torpedoes ; but during the Russian war of 1854 57, and the American war of 1861 65, the torpedoes employed were simply submerged explosives, without any power of progression. One such kind is intended to explode when a ship strikes up against it. It comprises a hollow iron chamber, an anchoring ring, a charge of gunpowder, an iron can filled with lime, a glass con- taining sulphuric acid, pointed iron rods, and other appliances. When a ship strikes against the top of this apparatus, submerged to a small dis- tance below the surface of the water, it breaks or dislodges some of the mechanism, and causes the lime and acid to produce a heat which ignites the powder; an explosion ensues, which -may work great mischief to the ship above. Another kind is worked by electricity. Two electric wires, laid along the bottom of the sea, connect the torpedo with the shore, where electric batteries and other apparatus are placed. When a sentinel or watcher sees a ship arrive at the fatal spot, he establishes electric connection, and explodes the torpedo. As for any practical effectiveness, the torpedoes hitherto made have rendered nearly as little service to the art of war as the sub- marine boats to the art of peace ; but it is now the opinion that the system is susceptible of a very for- midable development. Tortoiseshell is the upper shelly covering of the tortoise or turtle. It consists of a great number of plates or blades overlapping each other like the slates of a roof. These separate blades vary greatly in size, shape, thickness, and colour, so that the most suitable application cannot be determined till each blade is examined separately As a new layer of the substance is formed every year, the shell thickens as the animal grows older. In reference to the wants of the animal, tortoise- shell is rather a very thick skin than true shell. The shell of all species of the turtle has beautiful variations of colour, but that of the tortoise is the best, and the back shell is always better than the under or belly shell. As to which is preferred for particu- lar purposes rich dark brown, markings of golden yellow, light red, pale yellow, c. this is matter of varying taste and fashion. Tortoise- shell is worked up into workboxes, combs, tea-caddies, snuff-boxes, cabinets, spectacle-cases, and nume- rous other articles. The remarkable properties of the substance render it amenable to many varieties of manu- facturing treatment, (i.) Welding Small pieces may be joined by a true welding process, by scraping and thinning the edges, overlapping, and pressing under the influence of heat. (2.) Softening. Boiling water softens it to some degree, and facilitates many modes of treating it. (3.) Sawing, When dry and cold, the tortoiseshell yields easily to the action of a fine saw. (4.) Stretch- ing. When a slit is made, and the piece softened by heat, the slit can be so stretched out and worked as to form the ring for an eye-glass or spectacle frame. (5.) Moulding. As the substance becomes softened by boiling water, it admits of being pressed into a multitude of forms, by the use of iron moulds, dies, and counterdies ; by these means boxes and ornaments of various kinds are made. (6.) Pressing. There is another kind, of moulding, much practised in France, whereby frag- ments of tortoiseshell in the forms of cuttings, shavings, turnings, til- ings, dust, and the like, can be TOU 400 TOY collected into a kind of stiff putty by the action of boiling water, and pressed into moulds or dies. (7.) Veneering. Thin plates of tortoise- shell are often applied as a veneer to the surface of wood by gluing, the back of the veneer being painted in rich colours, to hide the grain of the wood and to heighten the tints of the shell. (8.; Inlaying. To in- lay or incrust tortoiseshell with gold, silver, mother-of-pearl, &c., the latter is driven into the very sub- stance of the former by the com- bined influence of softening and heavy pressure. Touchstone. The old assayers and refiners of the " noble metals," gold and silver, were wont to employ a touchstone to give them some rough idea of the quality of a piece of gold. This touchstone was a hard black stone, brought from Asia Minor ; but it is now found that a bit of black basalt will answer the same pur- pose. The assayer makes a number of touch-needles, one with pure gold, one with 23 of gold to I of copper, one with 22 gold to 2 copper, and so on. Each of these, rubbed upon the touchstone, leaves a streak, more or less red according to the quantity of copper in the alloy. "When he wishes to try the quality of a bit of gold, the assayer rubs it on the touchstone, and also rubs the touch-needles on the stone ; he can see by the eye which needle- streak corresponds in colour and appearance with his gold streak, and he thus has a standard of compari- son which enables him to judge approximately the quality of his bit of gold. There is also a mode of testing silver by touch - needles made of various combinations of silver and lead. But these methods now usually give place to a more refined and certain process, for which see ASSAYING. Tow. In FLAX PREPARATION it is explained that, when the fibres are heckled, either by hand or machine, they are separated into two kinds fine and long, called line; coarse and short, called tow. Tow par- takes a good deal of the quality ol cotton ; and on that account it can be prepared and spun on machines nearly like those for cotton, which are easier to work and manage than flax-machines. The tow is con- verted successively into cardings, slivers, and rovings, and is then spun into thread less strong than that made from fine flax. Toy Manufacture. This has become a very considerable branch of industry, especially in Germany and some other continental coun- tries. The wooden toys of the Black Forest are made in almost countless numbers ; and some of them in a most curious way. If the contents of the museum at Kew Gardens be examined, there will be found (as illustrations of the modes of using certain kinds of wood), several spe- cimens of the carved animals in- tended for the "Noah's Ark" col- lections for children, and of the modes of producing them. A ring is turned on the lathe, with a pat- tern depending on the kind of animal to be produced ; this ring is cut up into a great number of small pieces, by cuts strictly radial from the centre of the ring, the grain of the wood being in such a direction as to faci- litate this severance. It will be found that the profile of each piece bears a rough resemblance to some animal, which a few cuts by an ex- pert carver will suffice to bring to the proper form. The process is a very singular one, and might be imitated to advantage in many branches of industry where several copies of one pattern are to be produced. Wooden dolls, wooden houses, wooden toys of every de- scription are, in Germany and Swit- zerland, made by a very minute subdivision of labour ; each worker being employed exclusively in one particular part, and finishers in put- TRA 401 TRA ting all the parts together. Glu- ing, papering, painting, gilding all are organised departments. The tin soldiers which are such a source of delight to German children are made literally by millions, and are produced by the cheapest and quickest known processes in the working of metals. Whatever be the material employed wood, shavings, sawdust, paper, papier-mache, parchment, vellum, metal, plaster, gutta percha, india- rubber, wax, composition, glass, enamel, leather, hair, wool, cotton, silk the workpeople in those coun- tries display exhaustless ingenuity in devising modes of working them up into toys. The characteristics of French toys are taste and elegance ; as a consequence, French toys are more expensive than those of Switzer- land and Germany. The doll-manu- facture is one of the most important and lasting of all for here fashion comes into play; whenever ladies are prone to prefer blue eyes and golden hair, or black eyes and black hair, (t dolly" follows the fashion, to the manifest advantage of the doll- maker. Dolls' eyes are made mostly of glass beads, coloured or other- wise treated by hand ; and it is on record that a Birmingham glass manufacturer has received an order for ^500 worth of dolls' eyes at one time. Large numbers of toys are made in London and Birmingham, but not nearly so many as on the Continent, where Nuremberg is per- haps the chief wholesale depot for such articles. Toys to the value of 160,000 were imported in 1867. Trades and Occupations. For many purposes it is necessary to group the employments of men and women into distinct classes, giving a certain breadth of comprehension to each class. But it is found im- possible to do this with any approach to exactness, so much do the trades glide and blend into and among one another. When the Great Exhibi- tion of 1851 was planned, all the objects exhibited were grouped in thirty classes,- thereby grouping in a similar way the trades or occupa- tions whereby those objects were produced. WTien the International Exhibition of 1862 was planned, the classes were increased to thirty- six, irrespectively of the departments which related rather to the fine arts than to the industrial arts. At the Paris Exhibition of 1867 the group- ing was entirely different ; it com- prised ten groups, subdivided into ninety-five classes. The ten groups were: (i.) Fine Arts. (2.) Liberal Arts. (3.) Furniture, &c. (4.) Clothing, &c. (5.) Products of Mining, Forestry, &c. (6.) Ma- chinery. (7.) Food Products. (8.) Farming, &c. (9.) Horticulture and Living Plants. (10.) Special and Miscellaneous.* It would be much easier to point out defects in any past classification than to suggest one that shall be free from faults, so surrounded is the subject with difficulties. As to the actual num- ber of trades in England, the So- ciety of Arts once got up a list of no less than 2,500. Tragucanth is one of the many useful substances coming under the class of GUMS. Transfer Printing. As distinguished from lithography and electro - printing, the name Transfer Printing may be given to two or three special processes. In anastatic printing, invented by Bal- dermus in 1841, a copy is taken from a printed page of paper, without any type or any casting. The printed paper is moistened with dilute acid, and pressed by a roller on a clean zinc plate ; the plate becomes etched by the acid in the parts not touched by the printed ink. Then, a mix- ture of gum and acid being applied, the etched parts become wetted with it, but the other parts not. Next, an inked roller being passed over the plate, the ink is repelled from the etched portion, but attracted by D D TRE 402 TUB the printed portion : in other words, the old ink attracts the new ink. The plate, thus inked, is available for printing with the eopper-plate press. It was afterwards ascertained that some such process was known in England before Baldermus took up the matter. In chemitype, a varnish, applied to a zinc plate, is etched, then bitten in with acid, and then removed, leaving the engraving etched into the plate. The lines are filled up with molten fusible metal, scraped down to a smooth level. The zinc is then eaten away to a certain depth by strong acid, and the fusible metal left in relief to print from. In paneiconography the picture is either transferred to a zinc plate from a printed or litho- graphed page, or is drawn on it by hand with lithographic ink. A roller with new ink is passed over the plate ; the new ink adheres to the old, and is further thickened by a sprinkling of finely-pounded resin. Acid is employed to eat away the zinc be- tween the ink lines ; and by this means a relief-block is produced, which can be printed from by the common press. It will easily be seen in what way these several processes differ from those noticed under NATURE PRINTING. Treacle. The relation which this sweetening agent bears to common sugar is shown under SUGAR MANU- FACTURE. Tripoli Powder is prepared from a peculiar kind of earthy mineral, obtained first from Tripoli, but now from various countries. Different kinds, called grey, red, 3M& yellow tripoli, are all used as polishing ma- terials, when ground to a fine state. Troy Weight. As a matter con- nected with all the trades relating to gold and silver, we may refer to AVOIRDUPOIS for a notice of troy weight. A troy pound is to an avoir- dupois pound as 144 to 175 ; while the ounce of the former is to that of the latter as 192 to 175. Trussing 1 . (See CARPENTRY ; GIRDER.) Tube Making. Many different methods are adopted for making tubes. Metal tubes are made some- times by drawing a round bar of iron through a hole in a steel plate, nearly in the manner of wire-drawing, with a centre mandril to keep open the bore ; sometimes by bending a strip into a cylindrical form, welding the edges, and finishing by drawing. But the best gun-barrels are now made by coiling a long strip of metal round a mandril, and finishing it into a tube by welding, hammering, and other processes. Gas-pipes and boiler-tubes are mostly made either by the first or the second method. Brass tubes for telescopes are bent round, soldered, and drawn. Orna- mental tubes for pencil-cases and other small articles are made by drawing through holes, which give the pattern as well as the form. Lead pipes are noticed under LEAD-PIPE MAKING. Tin tubes for collapsible colour receptacles are made by draw- ing out a short thick tube into a long thin one. For plan of making tubes by casting metals when in a molten state, see CASTING AND FOUND- ING and CYLINDER CASTING. Tube Well. This is a very in- genious contrivance, first brought into use in America in 1866, and in England in 1867. Its object is to obtain a small supply of water in a very short space of time. Wherever there is water within a few feet of the surface, the tube-well willsoon render it available. The apparatus consists, in the first place, of an iron pipe an inch or two in diameter. This can be driven vertically into soft ground by means of an iron rammer of ^ cwt. ingeniously suspended over it, and worked with a pulley by two men. The lower end of the tube is closed and pointed ; but there are numerous small lateral orifices near the bottom. When the tube reaches a watery stratum, a handy little pump is TUL 43 TITR attached to the top of it, and water speedily pumped up. Sometimes a depth of 10 feet suffices to reach water; if more than 14 feet, two or more lengths of tube are screwed end to end ; and in this way water has been brought up from a depth of more than 100 feet. Some of these tube-wells were advantageously used during the Abyssinian expedi- tion in 1868. Tulle is a thin silk lace, woven with very open meshes, and in narrow strips like ribbons. Tunbridge Ware. This is a kind of small cabinet-work made of wood mosaic or inlay. Thin veneers of various fancy woods are cut into very small pieces, and glued upon a foundation in definite order, gene- rally according to some geometrical design. Many of the articles in this ware have been superseded by the curious Scotch Boxes (which see.) Tuning 1 Pork, so far as its manu- facture is concerned, is simply a pronged piece of steel; but its adjust- ment for use requires much nicety. When the prongs are made to vi- brate by a smart blow, they emit a clear musical note each individual fork having its own pitch ; and any change in length, thickness, or width, changes the acuteness of this pitch. The tuning-forks made in England are usually adjusted to give the note called tenor C, which makes about 256 single or 512 double vi- brations in a second. Tunnelling- Machine. (See ROCK BORING.) Turbeth. Mineral was an old name for sulphate of mercury. Turbine. The turbine may be regarded as a kind of water-wheel laid on its side. Water enters the wheel down the hollow axis, and escapes at the circumference. In its passage it acts upon certain blades or radii, and thereby causes the wheel itself to rotate. The blades are curved in such a way as to assist the action. In some forms of turbine the water ascends the axis from below ; but in this as in the other case, it cannot escape at the circumference without setting the wheel in rotation. In a third arrangement the water descends through four tubes outside the wheel, enters between the curved arms, sets the wheel in motion, and then finds an exit through the axis. Many other arrangements of detail are adopted ; but in all of them the flow of water causes a horizontal wheel to rotate, and this rotation is applied as a working power for ma- chinery. The Nautilus Propeller (which see) is the reverse of this ; for steam power causes a turbine to rotate, and this rotation expels water in such a way as to propel a ship. There is a third mode of applying the turbine or centrifugal principle. We have just seen (i) that descend- ing water, working a turbine, sup- plies power for moving machinery ; while the Nautilus Propeller shows (2) that the turbine may be made to propel a ship. There is (3) the power of the turbine to raise water. This is exemplified in the centri- fugal pumps of Appold, Gwynne, Bessemer, and other inventors. A wheel is made to rotate by steam or any other power ; this wheel has blades peculiarly shaped, and is enclosed in an iron case. Water, admitted from a lower level into the case, enters the wheel at the axis, and escapes at the circum- ference, by virtue of the centri- fugal force which the rapid rotation of the wheel generates. The water is sucked up from below as fast as it escapes at the periphery. The height from which the water will be raised depends on the velocity with which the wheel rotates. The ar- rangement is best fitted for raising a large quantity of water to a small height. Visitors to any of the se- veral International Industrial Exhi- bitions will doubtless remember the magnificent working of some of the centrifugal pumps. TUR 404 TUR Turf. .Some of the kinds of fuel known by this name are briefly no- ticed under FUEL and PEAT. The turf often sold about the streets of London, in the form of flat cakes, is little other than dried spent tan from the leather factories of Ber- mondsey. Turkey Bed. The use of this favourite dye is illustrated under BANDANA HANDKERCHIEFS; CA- LICO PRINTING; DYEING. Turkey Stone. (See HONE.) Turmeric is the root, or rather tuber, of a plant largely grown in the East Indies. There are two varieties, the long and the round, generally about 2 inches long by half as much in diameter. According to the mode in which the tubers are pre- pared, the turmeric becomes avail- able as a colouring drag, as a condi- ment, and as an ingredient in curry powder and curry paste. It pro- duces a fine yellow, and is some- what aromatic in taste and odour. Turning-, the imparting of a cir- cular form to articles in wood and metal, involves the maintenance ot a steady rotatory movement of the article to be turned. Whatever be the form of lathe employed (see LATHE), the work is kept rotating, and the edge of the cutting tool is pressed up carefully against it. Sup- posing wood to be the material ope- rated upon, great care is needed to accommodate the tool to any vary- ing degrees of hardness or crooked- ness of grain. All the roughnesses are gradually cut off not in chips, but in shavings or thin fragments. Great steadiness of body, arm, and hand are needed in this work. For turning the legs of stools, chairs, and tables, or staircase rails, or bobbins for spinners, or other arti- cles in soft wood, the work is com- paratively easy ; but it increases in difficulty when hard wood or still harder metal is to be operated on. The tools with which the work is done are mostly chisels and gouges, flat and curved, with various kinds and degrees of slope given to the edges. A pattern is sometimes given to turned wood, not by cut- ting with a chisel or gouge, but by pressing up against it a small wheel called a milling tool. The chucks are infinitely varied in fonn, to suit the different kinds of work which they are to hold. According to the nature of the material, so must be the velocity which the turner gives to the work ; if too fast, he will either chip the work or chip his tools. In the following order the velocity of rotation must lessen : soft wood, hard wood, brass, bell- metal, copper, wrought-iron, steel, cast-iron. The lathe is provided with means for insuring these variations by pulleys, grooves, and bands. The turner depends greatly on his chucks for varying the nature of his work. The concentric chuck is the common chuck for all the usual kinds of turning ; the eccentric chuck allows the centre or axis ot the work to be shifted ; the oval chuck enables ovals or ellipses to be turned ; the geometric chuck produces various fanciful designs ; while the oblique and the epicycloidal chucks are used for still more intri- cate patterns. An arrangement for working in ivory is called the excen- tric cutter. Rose engine-turning, such as adorns the back of watch- cases, requires not only a peculiar chuck, but a special kind of lathe, to give an intricate combination of movements. All the more impor- tant works in turning, especially in metal, are executed with the aid of the highly-ingenious appendage de- scribed under SLIDE REST. Turntable. Among the mecha- nism of railways, irrespectively of what may be called the civil en- gineering, is the turntable, by which an engine or carriage may be shifted from one pair of rails to another. If there were sufficient space, the switch would be more TUR 405 TCJR simple, as the engine could be easily shunted at the points ; but at stations, where space is valuable, the turntable is much employed. It consists of a flat platform, cir- cular in shape, and mostly made of iron ; it turns upon a central ful- crum or swivel, and acquires a very easy movement by resting upon rollers or small wheels. On the upper surface are rails of the pro- per gauge, crossing each other in two or more directions. When an engine or carriage is brought well on the turntable, a slight pressure sideways will turn the latter round, and bring the rails which are on it in a line with a particular pair of j rails on the permanent way. Some- j times it is turned by a winch-handle, | worked by a man standing on the turntable itself. There is, in fact, a good deal of mechanism underneath, especially for lines where a large engine and tender are turned simul- taneously. Turpentine. All kinds of fir and pine trees, when the trunk is pierced, yield a thickish sap or juice. This may be separated by distillation into a resin and a vola- tile oil. The latter constitutes the spirit, oil, or essence of turpentine, a name abbreviated by the painter into turps. The chief kind known in commerce, common turpentine, is that of the Pinus sylvestris, a very abundant North American tree. If to be sold in a crude state, the juice is collected from the trees in earthen or stone jars ; if refined on the spot, a simple process of distillation sepa- rates the turpentine into liquid turps and solid yellow resin. When the turpentine dries on the wound of the tree into a whitish substance, it is known as pine resin or -white resin; and when this is further treated, it constitutes one kind of Burgundy pitch. The turps ob- tained from the crude turpentine varies from 5 to 25 per cent., much less in quantity, but much higher in value, than the resin. When the turps is re-distilled and rectified, it yields camphine, a spirit which burns with a bright flame, but usu- ally sooty and of unpleasant odour. Turps is an almost indispensable liquid in mixing paints. RESIN is described separately, and so is TAR, another product of the same tree. Venice and Strasburg turpentines, Canada balsam, and frankincense, all belong to the same class of exu- dations as common turpentine. We imported 40,000 cwt. of turpentine in 1867. Turquoise. This beautiful blue stone is found in masses in a hard clay soil in Persia. It is worked up at Mushed by lapidaries, who use nearly the same kinds of tools as are employed in England. No particular use is found for it except as a jewel or precious stone, for which it is much admired. Turret Ships. Captain Cowper Coles was one of the first to suggest that, if guns were placed in a revolv- ing turret on the upper deck of a ship, they might be pointed in almost any direction, and thus greatly increase their efficiency. The Royal Sovereign iron-clad, launched in 1864, was the first ship on a large scale intended to test this principle ; it was a timber- built three-decker, cut down at the bulwarks, and cased with armour. On the deck were built four turrets, cupolas, or shields cylinders pro- jecting only a few feet above the level of the deck. They were made of 5-inch iron plate, backed up in- ternally with 20 inches of teak. Two of the turrets carried two very heavy guns each, the others only one each. The turrets, by means of well-constructed cogs, wheels, pivots, windlasses, &c., revolved very easily, the guns revolved with them, and the training or pointing of the guns was effected by revolv- ing the turrets themselves. No wide- spreading embrasures were wanted ; therefore the openings in the tor- TUT 406 TWE rets were only just large enough for the mouths of the guns, and thus the gunners behind them were less subject to be shot by the enemy than under the usual arrangement. The turret construction is looked upon with very great interest, espe- cially in America and on the Conti- nent. A Monitor is the familiar name for a turret ship so very little elevated that the bulwarks stand only a few feet out of the water ; there is hardly anything for an enemy to aim at and hit, while the two or four turret guns are very formidable in size. Tutenag- is a hard but fusible alloy, suitable for some kinds of castings. It consists of 16 copper, 6 nickel, 13 zinc, and sometimes a little iron. Tutwork and Tribute. These singular terms, little known except in Cornwall and Devon, relate to modes of paying for labour in the tin and copper mines. The miners are virtually partners in the trade. Tutwork is sinking shafts, driving levels, and making excavations ; tribute is the digging and raising ot the ore ; while a third variety, dressing, is the preparation of the ore for smelting. The men form gangs or partnerships, and each gang agree on the price at which they will do the work ; they pay for their ~wn tools, gunpowder, and candles, but are supplied with timber, trucks, and machinery of all kinds. The tributers are the principal, seeing that they have to exercise a great deal of judgment and forethought. The contracts are made for about two months at a time. The men know generally the kind of ore which they will have to work, but cannot fully foresee the richness of the particular spot which they are about to attack. They are paid by a proportion of the value of the dressed ore raised. A kind of auction is held, at which the gangs bid against each other, each g:>n^ according to opinions formed before the sale. The lowest bidding gets the work that is. the lowest ratio or percentage of the produce. The tributers pay the dressers as la- bourers. So greatly do the veins vary in richness and in facility of working, that the tribute may be as low as $d. or as high as 15^. per 2os. of value. The system calls forth all the intelligence of the men, and is unquestionably a reasonable one. (See MINING.) Tweeds. The woven goods called tweeds constitute a special class of woollen manufactures in Scotland. It is said that the name has no connection with the well- known river, but arose out of a mis- take in an invoice, which presented the word tweel under the form of tweed ; the consignor shrewdly saw the value of the blunder, and esta- blished the name of Tweed (to which river Sir Walter Scott's novels gave great interest some forty years ago) as belonging to a class of goods made at Hawick and other towns near the Tweed. The fabric was a twill or tweel (as distinguished from a plain cloth), which, from its strength and flexibility, was found well suited for shooting and fishing garments. A fashion hence sprang up for tourists to wear tweeds when they went to Scotland ; and from this sprang extensions in two dif- ferent directions the making of tweeds in other places besides Scot- land, and the wearing of tweeds by other persons besides tourists. The West Riding of Yorkshire produces a vast quantity of this fabric, with any proportion of shoddy, and any proportion of cotton, that lowness of price may necessitate ; but the best tweeds, all new wool, are still made in Scot- land. At first there were certain colours, chiefly drab and grey, to which the manufacturers mostly adhered ; but by degrees a fashion arose of coa.bining two coloui'S in TWI 407 TYP the same yarn, thereby producing a pattern which was long a charac- teristic of the tweed class of goods. The tweel or twill of the fabric gives a peculiar elasticity which does not belong to plain cloth ; the absence of cotton warp and shoddy weft insures goodness of quality and permanence of dye ; while the admixture of two or more colours affords scope for the display of taste in the production of pattern. The International Jury of 1862, speaking of these tweed fabrics, said: "To the Scotch manufac- turers belongs the credit of having found out what the public like, and of having led for a considerable period the public taste. So largely have their productions been imitated on the Continent, that many of the choicest fancy trouserings of France and other countries are easily trace- able in design and colouring to their Scotch origin." Twill is the name for a particular kind of textile goods, in which the weaver gives a sort of diagonal ribbed appearance to the surface. The weft threads do not cross alter- nately under and over the warp, as in plain weaving, but over two and under one, over three and under one, over three and under one and two alternately, or with other variations. Sometimes it passes over six at once, and then under a single one ; and in special kinds of satin it may even be fifteen at once. All twilled fabrics necessarily present a twill on both surfaces, though reversed in direction. This effect is produced by increasing the number and modi- fying the action of the healds in the loom. Satin, bombazine, and kersey- mere are three among many varie- ties of twill. (See further under LOOM, HAND and MACHINE, and WEAVING.) Type. So long as a whole page of a book was printed from one engraved block of wood, or one cast plate of metal, printing was necessarily a slow and expensive pro- cess; but when Gutenberg, Schaeffer, Faust, and Coster (one or all of them) invented movable types, a great advance was made, seeing that printers were enabled to use the same types for any number of different books, by variations in the mode of grouping. The shape of the type varies considerably. There are the differences between Gothic, Roman, Italian, Egyptian, Thick, Hair, &c. ; the differences be- tween capitals and small letters ; the differences in size between large type, medium type, small type, &c. There are about a dozen sizes of type used in ordinary printed books, known by names which have cer- tainly something very odd about them Great Primer, English, Pica, Small Pica, Long Primer, Bourgeois, Brevier, Minion, Nonpareil, Ruby, Pearl, Diamond. Large types used for posting bills are not here in- cluded. A. fount of type comprises not merely twenty-six types for the twenty-six letters of the alphabet, but nearly 200 kinds altogether, to provide for large capitals, small capitals, italics, diphthongs, &c. There are, we say, nearly 200 kinds in each fount, but there is not the same number of each kind : q, x, and z, for instance, are very spar- ingly needed compared with a, e, and s. Printers find by experience that in average English literature the letters are wanted in some such ratios as the following : e 12,000 d 4,400 p 1,700 t 9,000 1 4,000 b i, 600 a 8,500 u 3,400 v 1,200 i 8,000 c 3,000 k 800 o 8,000 m 3,000 q 500 n 8,000 f2,5OO j 400 s 8,000 w 2,000 x 400 h 6,400 y 2,000 7. 200 r 6,200 g 1,700 Besides 4,500 commas (,), 800 semi- colons (;), 600 colons (:), 2,000 full stops (.), 400 to 600 large capitals of TYP 408 TYP each letter, 150 to 300 small capi- tals of each letter, figures, spaces, &c. The whole fount comprises no less than 150,000 separate pieces of metal, and weighs several hundred- weight. Type Composing-, or arranging the types for printing, is an impor- tant part of the typographical art. The compositor 's case is a wooden frame with a large number of cells or compartments. The upper case 'is for capitals, accented vowels, numerals, fractions, asterisks, &c. ; the lower case is for small letters, diphthongs, punctuations, spaces to place be- tween the letters and words, &c. The cells are of different sizes, seeing that many more copies are needed of some letters than others ; and those which are most wanted are placed nearest to the hand of the workman. The compositor has a little apparatus called the composing stick, in which to place the types one by one. The composing stick regulates the length of each line. With the author's manuscript before him, the compositor sets up every letter, word, and line in succession, making as few mistakes as he can, and using small pieces of metal called spaces and quadrats to main- tain proper intervals or distances. In order to make a printed page look light and open, the lines are often leaded; that is, metallic spaces (uninked) are placed between them. The compositor must have brains as well as fingers ; for he usually corrects the author's slovenly punc- tuation, and sometimes incorrect spelling, as he goes on ; and he learns by long practice to take up each little type out of its cell with its right end foremost and its right side uppermost. A good compositor can pick up 2,000 types per hour. The lines of type, as they are formed, are removed from the composing stick, and placed in a small frame called a galley; then collected to form a page ; then further collected to form a sheet of 8, 12, 16, 24, &c., pages. All the types for one sheet are placed together in an iron frame called a chase, by the aid of append- ages termed furniture, side-sticks, foot-sticks, quoins, shooting-sticks, and a mallet. More correctly, there are two chases for each sheet, one for each side or surface, called the inner form and the outer form. By taking the letter m as a standard, the printers have an easy way of estimating the number of letters in a page ; and the compositor is then paid so much per 1,000 letters. Errors are corrected, redundancies removed, and deficiencies supplied, by picking out some of the types from the form, and putting in others a tedious kind of work, which requires much reading and exa- mination for its due performance. When the printing is finished, the types are distributed that is, re- leased from the chase and placed back again in the composing cases, ready to use for some other work. The compositor (who includes this labour in the price per 1,000 which he re- ceives) picks out the types and dis- tributes them with wonderful ra- pidity and accuracy. He can dis- tribute 50,000 letters in a day. If the work is to be stereotyped (see STEREOTYPE), the printing is not effected from the types themselves ; the letters are distributed imme- diately after taking the impression for the stereotype plate. Type-composing- Machines. Machines exhibiting wonderful in- genuity have been invented to ex- pedite the work of the compositor. Secondary reasons have interfered with their commercial success ; but their mechanical beauty is indis- putable. Sorensen's machine has a kind of keyboard like that of a pianoforte, each key governing a particular type. When a key is pressed down, a type is detached by a wire from a groove in a cylinder ; thence into a funnel ; thence into TYP 409 TYP another groove, where it places it- self by the side of the preceding type. There are very delicate ad- justments whereby the types can only fit certain grooves in the cylin- der ; and this is made to assist in distributing as well as composing. Rosenberg's machine also has a key- board; but here the types are ranged in vertical lines in front of it, from which they fall and arrange them- selves on an endless band when the keys are pressed down. Young's machine has the types so arranged that they pass along converging grooves to the receiver, and arrive at the adjusting place in their pro- per order. Hattet sley 's machine has a small piston, which, when a key j is touched, rises against the lowest letter in the type-reservoir, and libe- rates it for action. Alden's machine has the types arranged in cells around the circumference of a horizontal wheel ; the wheel slowly rotates ; several boxes rotate with it ; and the boxes receive or pick up the pro- per types from the respective cells. Mitchell's machine combines some- thing of Rosenberg's endless-band action with Young's converging grooves ; but there are numerous other pieces of mechanism of a most ingenious kind. The machine is in two distinct parts, for the composing and the distributing. There are several other machines, most or all of which have the keyboard action. When it was said that Young's ma- chine could compose 13,000 letters per hour, and that Mitchell's could rise even to 21,000, hopes were en- tertained of a grand reform, and that the 50,000,000 letter-types set up every day in the United Kingdom, in our vast printing arrangements, would henceforth be effected by ma- chinery. This expectation has not hitherto been realised. Human brains musfkz employed in "justi- fying " the types to arrange them into lines; to accommodate the spaces between the letters and the words ; and to correct the numerous errors which invariably arise in composing. No machine can do this kind of work ; and it has not been found, after a good deal of trial, that the work of the machine, plus the work of the brains, effects any material saving of time or money in the end, taking an average of all the work done in a printing-office. Very favourable balance-sheets have been put forth, but the leading printers do not seem to place much faith in them. We believe that Hattersley's machine is permanently employed in some of the newspaper offices. Type Founding-. Printing types are made of a mixed metal, better than iron or copper (which, being too hard, would cut the paper), and better than tin or lead (which, being too soft, would be flattened under the action of the printing-press). An alloy of 3 or 4 of lead to I of an- timony is found to make good type- metal ; but each type-founder has his own favourite recipe. In making these types there is first an en- graved punch, with the letter at one end; the letter is formed by ham- mering and filing while the steel is in a softened state. From the punch a matrix, or reverse impression, is obtained, by stamping upon a small slip of copper. From the matrix a type is made by casting in type- metal ; and this type is, like the original punch, worked with the letter in relief, or raised. The cast- ing takes place in a type-mould, which has the matrix at the bottom, and steel sides to determine the slope and size of the body or stem of the type. The mould is hinged in two parts, in such a way as to be opened and closed with great fa- cility. The type-metal, kept melted in a small vessel, is at hand. The caster holds the mould in his left hand, and pours the requisite quan- tity of metal into it with a little spoon. The type solidifies almost instantly ; a spring is loosened which TYP 410 CJMB opens the mould ; and the type falls out. So quickly is this done, that the caster can make 500 in an hour. When cold, the types have the bit of superfluous metal at the other end broken off from them ; theyare rubbed on a gritty stone to remove roughness, and are polished to bring the sides and ends to an exact size and shape. Type - founding- Machines. Attempts have often been made to produce many types at once, either by casting or stamping ; it can be done, and it is simply a commercial question whether the machine plan will in the end be more economical than the hand method. In John- son and Atkinson's machine the types push one another out of the mould as fast as they are made ; and then the machine performs all the operations of dressing the sides and ends of the types. In the type- founding machine used by Messrs. Miller and Richard, of Edinburgh, the type-metal is kept in a melted state' in a cylindrical iron vessel, one side of which has a spout or lip at the top ; near it is a frame con- taining the mould. This frame has an oscillating or reciprocating motion, which alternately carries it to, and withdraws it from, the ves- sel. At a given instant, when the frame is close to the melting-pot, a kind of piston is moved, which allows a definite quantity of molten metal to flow over into the mould. This done, the mould is drawn backward, opened, and the hot but solidified type emptied out into a tray. A current of air is kept play- ing against the mould to prevent it from being too highly heated. It is said that one man with this ma- chine can cast about three times as many types as an experienced hand- caster, but that the types require more dressing. u. Ultramarine is obtained from the beautiful blue mineral called lapis lazuli. The best stones are reserved for jewellery, the next for Florentine mosaic, and the others for the ultramarine makers. For the last-named purpose the stone is ground to powder with water, dried, kneaded into a clay with oil and resin or wax, left for several days to harden, washed repeatedly, and the water from each washing left to deposit a fine sediment : this sedi- ment is the exquisite blue colour, ultramarine. Other methods are adopted ; but the proportion of co- louring matter in the stone is so small, and the processes of obtain- ing it so slow and tedious, that the pigment is veiy costly sometimes twice as much as its weight in pure gold. The shades of blue are in- finitely varied, but always beautiful; and the miniature-painter and the enameller are very choice in the selection of tints. The high price led French chemists to try whether ultramarine could be made by other and cheaper means : they have had a large amount of success ; for, by combining many substances in a series of chemical processes, they have obtained a precipitate which yields a very intense and beautiful blue, far cheaper than real ultra- marine, and applicable to most of the same purposes. Timber, found in a peculiar stra- tum in the island of Cyprus, is a brownish kind of earth, a sort of ore of iron and manganese. It is useful in making brown paints and var- nishes. Umbrella Manufacture. This branch of industry has become a large one at Birmingham, especially since the introduction of steel and iron stems, ribs, and stretchers. UND 411 UPH Even the better kinds, made to a considerable extent in London and elsewhere, are supplied with the metal - work from Birmingham. After supplying a very extensive home demand, we export to the value of 200,000 annually. Undockingr. In the ordinary mode of launching a ship (see LAUNCHING), the vessel, being built upon ways (beams sloping gradually down to the river), is loosened from her fastenings when about to be launched, and allowed to slide down to the bosom of the river or sea. But it becomes more and more difficult to effect this, now that ships of enormous weight are built. The Great Eastern and the Northumberland afforded examples of this. The alternative plan is that of undocking. The vessel is built on a level keel in a dry dock ; the gates are opened and water ad- mitted when the ship has reached the launching stage, and then she is quietly towed out. Such was the mode of undocking the Hercules (see IRON WAR SHIPS) in February, 1868. It requires an immense dock, constructed at vast expense, to do this ; but then the launching be- comes very easy work, and the dock will be immediately ready for laying down another ship. In the case of the Hercules, the dock was closed by a kind of caisson, or cellular dock-gate. At low tide this gate was opened ; the water entered, rose inch by inch around the mighty ship, and at length set it fairly afloat the depth of water at the follow- ing high tide being sufficient to lift the keel well off the floor and the ground. The men, working lustily at the capstans, and aided by a tug, worked her out into the broad Med- way. Unions are woven goods now very extensively manufactured, con- sisting of any two of these materials cotton, silk, wool, flax, or jute ; or even three of them. Usually, however, the term is limited to those which contain cotton, flax, and jute ; the term mixed goods being given to those in which wool is a chief in- gredient. Upholstery, although not a very clearly-defined word, generally means the application of textile goods to the furnishing jof rooms and houses. The Society of Arts has given a useful enumeration of the chief materials employed, as exemplified at the Paris Exhibition in 1867. Silk brocades, &c., were made of organzine yarn from France and Italy, and weft yarn from China and Japan. Reps and table-cloths of the best class were made of French wool and Swiss floss silk ; Utrecht velvet of goats' hair, spun in England ; horsehair cloth of Buenos Ayres hair for the best kinds, and French for the inferior ; woollen damasks of wool from the north of France; mixed goods of cotton and silk, cotton and wool, and silk and wool, derived from various sources, and manufactured largely in Alsace and Rouen ; tapes- try of unmixed English wool ; the embroidered cotton fabrics, figured muslins for curtains, calicoes and chintzes, cloth for covers, ticking, carpeting, &c., from various sources, chiefly French, but partly English. The figured fabrics used in up- holstery are woven in France by the Jacquard machine ; the plain fa- brics mostly by power-loom, but partly by hand - loom ; the em- broidery and tapestry by hand. The application of power looms to carpet- weaving is only now beginning. The French manufacturers and the Parisian upholsterers adopt a sys- tem whereby they bear in common the expense, and often loss, attend- ant on the introduction of new patterns. VAL 412 VEG V. Valonia, one ol the substances used in tanning, is the acorn-cup of an Asiatic species of oak, subjected to a few preparatory processes be- fore being used by the tanner. The large quantity of 400,000 cwt. was imported in 1867. Vanilla is obtained from the long cylindrical fruit of a tree growing in Mexico and the West Indies. When gathered, the fruit is exposed to the sun and dried to a certain degree ; then tied up into bundles of fifty pods each, and packed in tin boxes for shipment. Vanilla is much used in flavouring chocolate, cakes, sweetmeats, liqueurs, and iced be- verages. Vapour. The relation which vapours bear to other aeriform fluids is noticed under GAS and STEAM. Varnish. Almost all varnishes consist of resins or gum resins dis- solved in spirit or some other liquid. The varieties are very 'considerable : copal, mastic, lac, benzoin, colo- phony, amber, anime, sandarac, are among the solids or resins ; alcohol, ether, naphtha, turps, sweet oil, linseed oil, are among the solvents or liquids employed ; and various colours are given to the varnish by the use of indigo, saffron, cochineal, gamboge, arnatto, tur- meric, and other substances. It follows from this threefold list that the number of different varnishes may be varied almost infinitely ; but copal, amber, and anime are the chief among oil var- nishes ; and mastic, lac, and sanda- rac the chief among spirit var- nishes. The former group, being most durable, and taking the best polish, are used by coach-makers, japan-workers, and house deco- rators ; the latter group consists of varnishes not suited for much ex- posure to the air, but adapted for cabi- net-work, lacquer, pictures, maps, and toys. Other technical names for varnish are cabinet, carriage, -wain- scot, white hard, brown hard, crystal, and black varnishes. Much careful mixing, heating, boiling, stirring, straining, and evaporating are ne- cessary in the varnish manufacture : it is rather a perilous trade, owing to the inflammability of almost -every one of the substances employed. Vegetable Ivory is the fruit or nut of a species of palm growing in South America. The fruit at first contains a sweetish liquid, which gradually thickens in consistency until it becomes quite hard. The so-called vegetable ivory is, in fact, the hardened albumen around the embryo, taking the place of a hard lining to the shell of the nut ; for there is always a rough kind of rind outside it. At the International Exhibition of 1862, numerous small articles in vegetable ivory, turned and carved, were shown. Vegetable Leather. (See LEA- THER SUBSTITUTES.) Vegetable Parcnment is made of unsized paper, soaked in dilute sulphuric acid. The paper undergoes a very remarkable change by this simple process ; it becomes nearly as tough as parchment, and for some purposes of writing and drawing is preferred to it. Vegetable Substances used in the arts are so varied as almost to defy enumeration. .When the Commissioners and Juries of the several International Industrial Ex- hibitions came to classify the objects exhibited, they divided these vege- table substances into some such groups as the following: (i.) Fi- brous substances. (2.) Wood, and materials for basket-work. (3.) Vege- table gums, resins, exudations, and the like. (4.) Dyeing materials. (5.) VEL 413 YEN Tanning materials. (6.) Starches and gum substitutes. All these are irrespective of food in its numerous forms of course the most important sendee which the vegetable world can render to man. Most of the materials for manufactures will be found briefly noticed under their proper headings. Vellum. (See PARCHMENT.) Velvet. This textile material, perhaps the most beautiful of all varieties of woven goods, owes its peculiarities to a nap, pile, or down on the surface, produced "by a special management of the warp and weft threads ; or rather, in addition to the ordinary warp and weft, there are other threads interwoven in such a way as to present a series of loops, standing up above the surface of the web. In CARPET MANUFACTURE it has been explained that Brussels carpets have loops of this kind left permanently standing ; whereas in Wilton carpets the loops are cut, so as to present a number of ends of threads standing up vertically. Now velvet, whether of silk or cotton, is a kind of Wilton carpet. Brass wires are woven in temporarily, run- ing across the breadth of the web ; each wire has a groove along its upper surface ; a knife, dexterously passed along this groove, severs all the threads resting on it ; and this severance not only liberates the wire, but causes each loop to pre- sent two loose ends. Veneer is a very thin film of wood applied to the surface of a thicker piece. Its primary object is usually cheapness, to economise costly wood by making the unseen parts of a kind less costly ; and in this respect it resembles a surface of stone to a brick building, or of marble to one of stone. When veneers could only be cut with a pit-saw or any kind of hand-saw, they could not possibly be made very thin or veiy regular, because the movements of the saw could not be accurately adjusted during every part of the cut; but when machine-saws were invented, a new power was given to the veneer-cutter. Veneers can seldom be cut less than \ inch thick by hand, and this only in small pieces. The circular saws, now generally used for this purpose, waste a good deal of wood ; but they have counter- balancing advantages. When of large diameter (say as much as 20 feet), they are built up of segmental pieces. The edge is made nearly sharp, and the teeth fine; they will cut veneers of any size so thin as j 1 ^ inch. The veneer-mill is one variety of Saw Mill (which see), in which, by the aid of axles, pivots, pulleys, drags, racks, pinions, tooth wheels, clutches, adjusting screws, guide-plates, and other mechanism, the timber is pressed up against the teeth of the revolving saw. The beautiful regularity with which a large sheet of veneer is thus cut, almost as thin as cardboard, bears witness to the accuracy with which the saw is adjusted. Another mode of making veneers is by planing, shaving, or slicing. The scaleboard for hat-boxes, as thin as a veneer, is, in fact, a shaving, cut from the surface of a plank by a kind of plan- ing machine. Veneers can be cut from a solid cylinder of wood by making a continuous shaving, be- ginning at the surface and bending in spirally towards the centre; a peculiar knife-edge is required for this, and the spiral shaving is after- wards flattened out to a thin veneer. Ivory veneers 12 feet by 2^-, and 40 feet by 12 inches, have been cut by this means from one single ele- phant's tusk. For cutting straight- grained and pliant woods, the elder Brunei invented a machine, in which a very long and sharp knife had a re- ciprocating horizontal motion given to it ; a large timber, placed be- neath the knife, had a thick uniform shaving or thin veneer cut from its surface by this means. All the YEN 414 VEN choicer kinds of wood rosewood, mahogany, satinwood, bird's-eye maple, pollard oak, &c. are largely used as veneers. Veneering is the fastening of a thin sheet of veneer upon a substra- tum of commoner wood. The ve- neer and the wood are both rough- ened with a toothing-plane, the better to hold the glue. Both, when made quite warm, are plentifully coated with glue ; the veneer is laid on the wood, with the glued surfaces in contact ; clamp-screws are fixed on temporarily, to keep the veneer tightly pressed down in every part ; and by the time the glue is set and dry, the veneer has become firmly united to the foundation. The pres- sure is so great that very little glue remains within, but the union is per- fect. This work requires care even when the surface of the foundation is flat ; but when it is round, hol- low, ogee, or curved in any other way, tools called veneering hammers are used, to press the veneer forci- bly in every part ; the two pieces of wood and the tools are kept hot during this process ; and, if the sur- face be large, many men are briskly employed upon it at the same time. A peculiar kind of cabinet-work called press-work, of recent intro- duction, consists in making the en- tire substance of the wood by means of several veneers placed one upon another. Five, seven, or even nine thicknesses are used ; glue, heat, and pressure being the modes of insuring perfect adhesion. The grain of the veneer is made to cross in different directions. Being very strong and yet very light, this pressed work is used for chair-backs and other articles of furniture. The inner veneers need not be of such choice quality as the outer. Venetian Glass. Some of the peculiar features of this fanciful kind of glass are noticed under AVENTURINE. Ventilating. As the air in a room is vitiated by the breathing of the inmates, and by the burning of the fires, gas, candles, or lamps, as well as by other agencies, it is necessary to provide means for the escape of this air and the admission of fresh. In an ordinary way, doors, windows, and chimneys are the avenues for inlet and outlet ; but very little attention is paid to the suitability of the arrangements. It is calculated that 500 cubic feet of air pass though the lungs of an average man in an average day of twenty-four hours ; this air loses some of its oxygen, and imbibes carbon, during the passage, and thus respired air is a very different thing from zVzspired. Then, again, fires, candles, and lamps of all kinds rob the air of some of its oxygen, and produce carbonic acid gas and watery vapour. So great are these causes of deterioration, that some physicians assert that there ought to be 1,200 cubic feet of fresh air per hour, for every adult male living and sleeping in a barrack or other building. There is usually warm air going out from chimneys and upper windows, and cold air coming in at lower doors and windows, because warm air is lighter than cold ; but it is only in well- constructed buildings that arrangements are made to balance these two quantities in proper pro- portions. In all except the more scientific arrangements, ventilation is managed by accommodating the natural ascensive tendency of warm air. If vitiated air were heavier than fresh, ventilation would be difficult ; but it is warmer, lighter, and therefore ascensive. How to get fresh air into a room, how to get foul air out of it these are the problems. As open doors and windows are never so arranged as to adjust the proper quantities, arti- ficial apertures are made. Some- times air-holes are made near the floor of a room to admit fresh air; YEN 415 VEN but this occasions a stratum of cold air near the feet, not always either agreeable or healthy. Many sani- tary physicians recommend air-holes near the ceiling, if there is an open fire-place to draw down the air so admitted. Perforated air-bricks, perforated zinc or iron sheet, hinged valves connected with air - boxes opening to the outside of the build- ing, perforated panes of glass these and numerous other contri- vances are used to admit air into rooms, or else to afford exit for the impure air. Sometimes, in addition to a chimney, there is a foul-air shaft, rising to the top of the build- ing. A kind of balanced valve was invented by Dr. Franklin, and much improved by Dr. Arnott, for inser- tion in the side of the chimney; much of the impure air of the room is drawn away through this valve by the ascensive tendency of the hot air in the chimney. An arched ceiling, with a foul-air channel rising in some way from its highest or central part, is a very effective ventilating arrangement; but it is only in a few buildings that such a plan could be adopted. In the old House of Lords, Sir Humphry Davy made openings in the ceiling, with a copper tube over each, for the escape of vitiated air. It is now admitted that warming and venti- lating a large building ought to be parts of one comprehensive arrange- ment, each part adding to the effi- cacy of the other. Examples of these compound systems are given under WARMING AND VENTILAT- ING. A mode of drawing out the vitiated air from mines and large buildings, by a kind of suction, is noticed in the next article. Ventilating- Pan. When a drum or wheel is rotated, the centri- fugal force tends to drive out water or air from near the axis towards the circumference. This has sug- gested a ventilating fan for draw- ing out impure air from mines and large buildings. Desaguliers in- vented such a fan many years ago. It was a hollow wheel, 7 feet dia- meter by I foot broad or deep ; it was divided into compartments by twelve radial partitions, all opening outwardly into a circular space near the fire-place, and inwardly into a central opening. This wheel re- volved nearly in contact with an outer cell. By so doing, air was sucked by the central opening into the twelve channels, along these to the circular space, and thence into an exit-pipe. The partial vacuum thus formed at the centre of the wheel incited a rush of air from the shaft of a mine with which it was placed in combination ; and in this way foul air was drawn out of the mine. This wheel was rotated by hand ; but the descent of a weight might be made to produce the effect; and so, of coxirse, might water power and steam power. All the ventilating fans since invented have acted on a similar centrifugal prin- ciple, however modified in detail. Fairbairn and Lillie's fan, much used in the large factories of the north, will produce such a powerful draught as to draw all the vitiated air out of a gallery 200 or 300 feet long ; and by connecting pipes, all the rooms in all the successive stories can be similarly ventilated. Or it may be used for drawing all dust and fibres out of the workshops in which cotton and other materials are treated. Or it may draw air out of lofty shafts, or even blow air into forge fires. In one form of construction, the wheel is concentric with the case in which it works ; but a greater working efficiency is obtained by making the two ec- centric, the wheel being nearer to one side of the case than to the opposite. In Chaplin's duplex pres- sure fan there are two wheels instead of one, but both revolving on one axis ; the air is drawn from the one to the other, and thence discharged YEN 416 VER with greater force than when only one wheel is used. The partitions, vanes, radii, or spokes, which divide the wheel into compartments, vary greatly in number and form, according to the mode in which the inventor intends them to act. Other improvements,introduced by Buckle, Cowper, Platt, Schiele, Nasmyth, Rammell, and other engineers, have so improved the ventilating fan, that it is now rapidly superseding the other blowing machines giving a uniform blast of air instead of a series of puffs. A peculiar action of the fan has been devised for propulsion through tubes. (See PNEUMATIC DESPATCH.) Ventilating- Mines. As the air in a deep mine is very unfit for respiration, ventilation is needed. Even when there is, as in copper and tin mines, no choke-damp or dangerous 1 explosive gas, there is still contamination through the burning of candles, the smoke of gunpowder, and the breathing of men. It is difficult to insure venti- lation, because the underground workings ramify into a vast net- work many miles in extent. Winzes are often very useful ; that is, small vertical air-channels from one level to another, giving con- taminated air a chance of escaping I upwards, and so gradually to the open air. In some mines these winzes are very numerous. In many of the larger mines an air-shaft is constructed at some distance from the main shaft, and going down to as great a depth ; this becomes avail- able for working as well as for ven- ! tilation. By placing doors in various positions in the horizontal passages, and by opening and closing these, the bad air may be made to take a particular direction, and so escape into the atmosphere ; by kindling a large fire at the bottom of a vertical shaft, a current of hot air is made to ascend, and this current determines the direction of the bad air; by ventilating engines and fans, the bad air is drawn out by a species of suction ; and by varying the use of all these melhods, the mine is more or less ventilated. But the ventila- tion of a coal mine is much more important than that of a tin or copper mine, owing to the greater foulness of the air. A second shaft is often dug to aid in this ventila- tion one shaft being called the downcast and the other the upcast. Passages being made between them, and a fire kindled at the bottom of the upcast, a current of air is made to take a determinate direction ; and this air traverses many miles of underground galleries before it reaches the upcast shaft. If there is no second shaft, the single shaft is divided into two by a brattice or timber partition, and the two divi- sions made into an upcast and a downcast. Some have even three divisions for working, for drainage, and for ventilating. Doors to close some of the passages temporarily, as a means of controlling the direc- tion of the current of air, are opened and closed when needed by boys. The rich Hetton Colliery is said to have 150,000 cubic feet of air per minute sent into its workings. The large fires kindled at certain parts of a coal min^ are the chief agents in producing a draught for ventilation ; but there are also used cowls on the top of chimney shafts, to take ad- vantage of the direction of the wind; a ventilating fan at the top of the shaft, worked by steam power ; and a high-pressure steam boiler at the bottom of the shaft, which sucks in bad air from the horizontal galleries, and drives it up the shaft. Verdigris, an acetate of copper > is made in a curious way. Plates of copper are piled up,with ferment- ing grape-skins between them, and left for several weeks. A crust forms on the copper, which is scraped off, and made into a kind of paste with vinegar ; this paste is VER 417 VIN moulded into thickish green masses of verdigris. It can also be made from plates of copper acted upon by cloths dipped in vinegar. Verdigris is useful in many of the arts, and in surgery; but being poisonous, it requires to be treated with cau- tion. Verditer, made by a complicated treatment of salt, sulphate ol copper, potash, and muriatic acid, is a very useful paint, blue or green accord- ing to the details of the making. Verjuice is an inferior kind of vinegar, made from the wild crab- apple, from sour cider, or from the juice of unripe grapes. Vermicelli, better known in Italy than in England, differs in little except size from Macaroni (which see). Vermilion. This beautiful colour is prepared artificially from mercury and sulphur. Various plans are followed in China, India, and Hol- land for making it. The Chinese use 4 parts mercury and I sulphur ; the Indians, 42 mercury and 8 sulphur ; the Dutch, 1 70 mercury to 50 sul- phur varying, therefore, from about 3^ to 5 times as much mer- cury as sulphur. The processes are various combinations of heating, pounding, sifting, steeping, volati- lising, subliming, &c., the vermilion settling as a powder upon the sides of a vessel prepared to receive it. Why vermilion is often called CINNABAR is explained under that heading. Vermilion is subject to much adulteration in the market. Brick-dust, oxide of iron, red-lead, and dragon's blood are often em- ployed for this purpose producing a red, but not the beautiful red which belongs to the substance. There are tests which enable the chemists to detect these adultera- tions. The artist colour-makers have to subject vermilion to further r>r cesses before it will be suitable for their purpose. Vine ; Vineyard ; Vintage. These subjects are briefly noticed in connection with WINE MANUFAC- TURE. Vinegar Manufacture. Vine- gar bears a certain chemical relation to beer and spirits. When grain and other vegetable substances have been fermented, sugar is converted into a kind of beer ; when further fermented, it mor e resembles spirit; and a further process yields an acid or sour product, which is, in fact, vinegar. Practically, the vinegar manufacture is conducted as follows, (i.) Malting. Most vinegar is made in England from malt. The first process is mashing^ to produce a sweet liquor called -wort. This is so like the corresponding process in the making of beer and ale, that it will suffice to refer to BREWING. (2.) Storing. In one mode of making vinegar, after the wort has been fer- mented into wash or gyle, it is aceti- fied by storing. Casks filled with it are ranged in close rooms, and exposed to the action of stoves or steam-pipes. (3.) Fielding. In an- other mode, the wash or gyle, in- stead of being stored, is placed in casks in the open air, with bung- holes open to admit the action of the atmosphere upon the liquid. This fielding, as it is called, is a very slow process, occupying several months ; at the end of this term the wash is found to be acetified into vinegar. (4.) Clarifying. After the vinegar is made, it is drawn off into a store vat, where it is allowed to flow repeatedly through a mass of raisin-stalks and skins, or some other filtering medium. This pro- duces a clarifying or clearing effect. Many substances may be used in- stead of malt as a source for vine- gar. A solution of sugar with a little strong spirit ; a mixture of brandy and honey ; in fact, every- thing containing sugar may be made to yield alcohol, and then every- thing containing alcohol may be made to yield vinegar. Thus it hap- VIO 418 WAF pens that all kinds of wine, beer, and spirits, as well as all kinds of grain, meal, and sugar, are available. The process above described is that which 'is usually followed in the English malt-vinegar factories ; but many modifications are introduced in the wine-vinegar and brandy- vinegar factories, chiefly in the mode of causing every atom of the liquid to come under the action of atmospheric air. It has recently been ascertained by a French sa- vant, M. Pasteur, that the true agent in converting fermented liquors into vinegar is a minute living vegetable, almost in the low- est degree of organisation, and so small as to be barely more than s^th of an inch long. Violin. The construction of in- struments of the violin class seems rather a simple matter ; for there are merely a hollow body of wood, a solid wooden neck, a wooden peg or support inside the body, a certain number of catgut strings, pegs by which to screw them up, and a bridge to lift them up from the body. These pieces of wood and membrane are easily shaped and easily put to- gether. Yet no instruments vary more in value than violins; and neither mechanicians nor musicians can determine precisely how or why one violin should turn out so much better than another exactly equal to it in appearance. The resonant quality of the wood, i.e., its power of accommodating itself to various kinds of vibrations, is probably the chief element concerned in the mat- ter ; but the size and position of the holes in the body, the position of the supporting peg, and the quality of the strings, are all important points. The Amati, Guameri, and Stradivari families made the celebrated Cre- mona violins two centuries ago, which are now valued like choice old pictures. The whole group of bowed instruments including the violin, viol, viol de gamba, viola, viola d'amore, violone, violoncello, contrabasso, &c. depend funda- mentally on the same acoustic prin- ciples. Vitriol is a name still retained in manufactures and commerce, al- though scientific chemists have dis- carded it. Blue, green, and -white vitriol are, respectively, the sul- phates of copper, iron, and zinc ; while oil of vitriol has changed its name to sulphuric acid. Vulcanite. This is one of the preparations noticed under INDIA- RUBBER MANUFACTURES prepara- tions so valuable in the arts, because while some can be made more liquid, others can be made more hard and dense, than the gum itself. w. Wadding 1 , a soft warm lining for garments, consists of a layer of cot- ton as it comes from the carding engine, before it has advanced to the spinning processes. It is kept to- gether by cementing to tissue paper with a glue of melted size. The softest kind consists of a double layer, with the downy surface out- side. Wafers, the use of which has been lessened by the adoption of adhesive envelopes, are made of wheaten paste. Flour, water, isin- glass, or white of egg, and a colour- ing substance are mixed together, worked up into a very fine paste, pressed together between two iron plates, and baked ; a very few seconds suffice for the baking. When re- | moved from the plates, the thin | films are cut into wafers by means of hollow punches, acting upon many thicknesses at a time. Isin- glass wafers contain isinglass in- stead of flour, and require no bak- WAL 419 WAR ing ; they are thinner and more ad- hesive than the common kind. Gela- tine wafers are somewhat like them, but cheaper. Medallion wafers are produced by pressing a seal or me- dallion on a thin layer of pure glue, the seal being previously wetted with gum : by giving different colours to the glue and gum, the wafer may present a white bas-relief design on a coloured ground. Walnut Wood, the timber of the well-known fruit tree, is much valued in the arts. Being light, hard, and fine grained, it is used for gun-stocks, and for numerous kinds of cabinet-work. As a veneer for pianofortes it has recently come very largely into demand. Warming-. In warming rooms, houses, and buildings generally, the most obvious and primitive plan is to make an open Fire-place (which see), to present a cheerful appearance, without much considera- tion for the economy of fuel or the consumption of smoke. The next advance is to a close fire (see STOVE), in which these two matters are more fully considered. But there are other arrangements by which very large bodies of air can be admitted through the agency of a compara- tively small fire-place or furnace. These we will briefly pass in review, (i.) Heated Vaults. The Roman system of the hypocaust is a type of those in which a body of hot air is stored below or outside a building, and admitted to warm a room or hall. The actual fire-place was out- side, but the flues were under the floor, in what may be regarded as vaults. The Chinese adopt a similar system, underground flues warming the tiles with which the rooms are floored. (2.) Hot-air System. The cockle stove, called also Belper stove, imparts heat to a large body of air, and conveys the air through pipes to the rooms which are to be warmed. The stove or cockle is a domed cylinder ; around it is an air- space ; and around this space a thick mass of brickwork. The air in the space, greatly heated by con- tact with the stove, passes through apertures in the brickwork, and so into the hall or apartment which is to be warmed. This stove is only one among many varieties of the hot-air system. The stoves may be greatly varied in size and shape, the air-space in capacity and arrange- ment, the surrounding brickwork in thickness and apertures ; while the whole may be placed at varying distances under the floors of the building. (3.) Steam-pipe System. James Watt made a flat box into which steam was admitted; the steam, in condensing into water, gave out its heat, which was radiated into the room ; and thus was esta- blished a mode of warming buildings by steam. To use pipes instead of flat boxes was an obvious change ; and the steam-pipe system came gradually into use. It is not worth while to make steam for this pur- pose; the system is an economical one only where there is already a steam-boiler at work. It is cal- culated that a boiler large enough for a i -horse power engine will yield steam sufficient to maintain 50,000 cubic feet of air-space at a temperature of 70 Fahr. The ar- rangement of the boiler and the pipes may take any one of many different forms ; the great point is, ftiat the air to be warmed should be in contact with them, and then con- veyed in its warm state to the place where it is wanted. In one inge- nious arrangement there is a series of concentric cylinders ; the annular spaces are filled, half of them with steam and the alternate half with air ; a ventilating fan drives fresh air through these last-named chan- nels ; and the air passes out at tke other end warmed by contact with the steam channels. (4.) Low- pressure Hot-water System. The use of hot 'water is now found to be WAR 420 WAR more economical and convenient than steam. It assumes two forms, low pressure and high pressure. In the low-pressure arrangement there is an exit pipe for hot water from the boiler, and another pipe for the water to re-enter. The water is maintained at a temperature a little below 212 ; it is made to traverse a pipe in and through the rooms ; it gives off its heat through the sub- stance of the pipe ; and returns to the boiler to be reheated. The pipe is not carried to any great height above the boiler. A circu- lation is maintained because the cooling water is heavier than the hot ; the one has a tendency to de- scend, the other to ascend; and a very small difference of temperature suffices to give a current to rather a large body of water. Modifications of this plan, introduced by Mr. Hood and other inventors, enable the engineer to warm three or four stories with one boiler placed in the basement. (5.) High-pressure Hot- water System. Here the water is heated to 350 Fahr. or more ; and as water at this high temperature has an immense bursting pressure, the apparatus requires to be made exceedingly strong. The boiler and the pipe are all one, a coiled portion of the pipe serving in place of a boiler. The pipe is of very much smaller diameter than on the low- pressure system, both for safety, and because every square inch of pipe has a greater heating effect. The intense pressure causes the cir- culation to be rapid ; the hot pipe gives forth its warmth to the air of the room ; and then the water de- scends to be reheated. It is custom- ary in large buildings (such as the British Museum) to have coils of pipes in various rooms and halls ; each coil forms a pedestal or mass ; and the hot water, passing through the whole length of pipe and coil, diffuses its warmth more equally by this means. The high-pressure system (due chiefly to Mr. Perkins) is suitable for larger and loftier buildings than the low-pressure. Warming: and Ventilating-. The details given under FIRE-PLACE, GAS STOVES, SMOKE CONSUMP- TION, STOVE, VENTILATING, VEN- TILATING FAN, and WARMING, describe many modes of supply- ing warmth to buildings, and many others for removing impure air, whether warm or cold. There re- mains to say a little concerning certain large operations, in which warming and ventilation are con- ducted as parts of one system. In 1835, when the Houses of Par- liament were about to be built, the late Dr. Reid devised a mode for warming and ventilating them ; and it was first tried in the temporaiy room which the Commons for a time occupied. There were double floors to the room, the under having seve- ral openings about 18 inches square ; while the upper one was pierced with no less than 300,000 small holes, about one-sixth of an inch diameter. Beneath the lower floor were wide passages, a hot-water pedestal stove, and folding doors so managed that warm air in winter and cold air in summer could be sentup through the openings, or air of various tempera tures at different hours of the day. The air, diffused in the space between j the two floors, then passed through | the small perforations, and spread over the house. The upper floor was covered with open-mesh horse- hair matting. A vertical shaft, 8 to 12 feet diameter by no feet high, produced the draught which gave a general ascensive power to the air. The room had a double ceiling, with a number of concealed open- ings in the lower one; the great draught drew up all the vitiated air into the space between the two ceilings ; from this space the air passed to the outside of the build- ing, then down a square shaft, and then entered the lower part of the WAR 421 WAR great ventilating shaft, where a coal fire was kindled. The draught occasioned by this fire sucked out all the air from the building. Air- screens, dampers, and other con- trivances modified the action of the apparatus. When the New Houses of Parliament were finished, Mr. Goldsworthy Gurney was intrusted with the warming and ventilating. He adopted a plan based upon that of Dr. Reid. The fresh air is fil- tered on entering the House. In winter it is warmed by passing over steam-heated iron boxes ; in summer it is cooled by a peculiar application of sprays of water. The prepared air passes upwards through minute perforations'into the House, the floor being covered with porous hair-cloth, to prevent the current from being felt as it used to be under Dr. Reid's arrangement. Two coke fires are kindled at the bottom of two shafts, one for the House of Lords and the other for the House of Commons. Passages connect these shafts with the spaces over the two ceilings ; and thus the vitiated air is drawn out nearly in the same way as that already described. As there are a vast number of rooms in this extensive pile of buildings, the hot- water system is adopted for warming them generally, irrespectively of the special arrangements for the two principal chambers. In the old Covent Garden Theatre, a mode of ventilation was adopted which the Marquis de Chabannes had sug- gested. Over the great chandelier was a wrought-iron funnel leading to a wooden shaft ; this shaft reached from the ceiling to the roof, and was surmounted by a cowl. The hot air accumulating around the chandelier passed through the fun- nel and the shaft ; while lateral pas- sages brought vitiated air from other parts of the house into the sides of the shaft; and there were small furnaces at different parts (out of the way of danger) to give an ascen- sive tendency to these collateral currents. There has been a very extensive adoption of some such plan as making the lighting of a room contributory to the -ventilat- ing; the light, whether a single gas- burner or a chandelier, serving as a furnace to give an upward tend- ency to a mass of heated and viti- ated air. The late Dr. Faraday in- troduced this plan in ventilating rooms heated by gas-burners. Syl- vester's plan, adopted in many pub- lic buildings, is to allow fresh air to pass through horizontal pipes be- neath the floor, then to warm it in a cockle stove, then to allow it to warm the room or building, then to pass up through holes in the ceiling to a space over, and then to escape. Steam-pipes or hot-water pipes placed in the roof give an additional ascensive power to the air. Scientific architects and builders have often succeeded in warming and ventilat- ing all the rooms in an ordinary dwelling-house by a judicious ar- rangement of flues and air-passages. In some of these plans there are fresh-air tubes running all up the house, horizontal pipes between the floor and ceilings, openings behind the cornices near the ceiling of every room, underground channels be- neath the house (with a cockle stove to warm the heating air in winter), and an outlet somewhere in the roof. These passages and valves are so arranged that fresh warm air enters every room in winter, and fresh cold air in summer ; while the air which has been vitiated is carried off. It is evident that such a plan can only be adopted while the house itself is being built; no patching afterwards would suffice. Warp; Warping. The pro- cess of warping, as a preliminary to weaving, consists in so arranging spun cotton or other yarn as to form the warp, or long threads. These threads are always harder, always more firmly twisted, than those for WAS 422 WAT the weft, or cross threads. The most general mode of arranging the warp is by means of the warp- ing machine. This is a skeleton cylindrical frame, rotating on a vertical axis. The bobbins with the yarn are set loosely on iron spindles in a separate frame called the traverse. There is another apparatus, the jack, between the cylinder and the traverse, contain- ing a number of needles through which the threads pass. By the mutual action of these three parts, when the cylinder or vertical reel is made to rotate, the threads are drawn off from the bobbins, passed through the jack, and wound spirally around the cylinder. If the warping is for plain goods, the threads are wound in two separate groups, one to be managed in connection with each heald in the loom ; each of these groups, called a lea, comprises half as many threads as there are to be in the width of the cloth. The yarn is thus warped. It is then beamed, or spread out on the yarn-beam of the loom ; the beam rotates, and the yarn is spread equally over and around it by the aid of a comb called the ravel. For what follows we refer to LOOM, HAND and MA- CHINE, and WEAVING. Wash, is a name given to the fermented wash at one of the stages in making alcoholic liquors, for which see DISTILLING. Washing- Machine. The wash- ing or rinsing of woven goods, in the large operations of bleaching and dyeing, is very generally done with dash-wheels. The cloth is put into a case or hollow drum, capable of rotating on a horizontal axis ; there are perforations in the exterior edge of the drum, and there is also an outer case which does not rotate. Wet cloth is put into the drum, and the drum rotated with great velocity ; the moisture, whirled out of the cloth by centrifugal force, escapes through the perforations into the outer case, whence it flows away through a pipe. Sometimes pressure between rollers is used, instead of centrifugal force. In the washing machines made for do- mestic use both of these methods are adopted, as well as others. In the rotating machines soap and alkali are put with the water into the drum. In one form, several wooden balls are whirled about among the wet linen, which they help to cleanse by their friction. In another, the linen is twisted into a kind of roll, and squeezed between rollers in a way somewhat imitative of the process of wringing. In a third, portions of the apparatus vibrate in a manner bearing an analogy to the rubbing action of the wrists and knuckles of a laundress. Many of the machines have rollers of india-rubber, between which the linen passes after washing, to effect the process of wringing. Watch. This beautiful time- measuring instrument differs from a spring-clock chiefly in the nume- rous contrivances for packing a great deal in a small space, and (except in repeaters) in the omission of the striking train. A vertical watch has a spring and balance for the regulation, instead of a pendu- lum. The small clocks made before the days of Huyghens and Hooke did not subdivide the hours into minutes and seconds ; but when the balance-spring was invented, this subdivision became possible, while still retaining a very small size for the entire mechanism. Considering a watch as a small spring-clock, there is a difference between the motion-work and the movement. The parts called the cannon pinion, minute wheel, hour wheel, and hands, constituting the motion work, can all be moved by the watch-key, without disturbing the actual going-train or movement ; it is in this way that the hands can be set right, as a distinct operation WAT 423 WAT from winding up. The watch is called vertical because it has a fusee with a vertical axis (see FUSEE), and cannot be made so thin or flat as might otherwise be the case. A horizontal "watch differs from the vertical in external appearance chiefly in being thinner or flatter ; but in the interior the arrangements vary much, owing to the almost interminable diversities in the form and action of the Escapement (which see). All the varieties of lever and duplex watches owe their names chiefly to the kinds of escapement which they comprise. English watches are regarded as superior to those of continental make in durability of construction ; but there is a large import of the cheaper kinds, chiefly from Switzer- land. For further illustrations see CHRONOMETER, CLOCK, ESCAPE- MENT, FUSEE, and the next article. Watch. Dials are usually made of fine thin sheet-copper, coated with an opaque white enamel. The pieces of sheet-copper are cut into squares, then into discs, then heated to redness, and worked into a con- vexity on one side and a concavity on the other. This is done by a hollow die of the proper size and shape, into which the copper is gently worked by a pressing tool ; and the piece of metal is gradually made smooth and symmetrical by perforating with the necessary holes, punching up the copper into the edges of the holes, squaring up some of the holes, and burnishing the edges. The enamel which is ap- plied to the copper dial thus shaped is either hard or soft, according to its ingredients ; it is a kind of opaque white glass, such as is described under ENAMEL. The best kind is used for the convex top of the dial ; an inferior kind for the concave bottom. Great nicety is required in applying an equable coating all over, mostly by means of a small spatula. The dial is then baked carefully in an enamel oven, and comes out with the ena- mel smooth, brilliant, and glossy. Any small defects are picked out by hand tools, and the holes filled up with pure enamel. When quite ready, each dial receives its array of hour-figures, minute and second spots, &c., in another kind of ena- mel, usually black, mixed up as a paint, and applied with a fine camel- hair pencil. "Water. This, the most important of all liquids, presents its uses in such multifarious forms that almost the whole range of science would have to be appealed to in the illus- tration of them. A few of the more salient properties only need be men- tioned here. Pure water, chemi- cally considered, consists of 8 oxygen to i hydrogen by weight ; whatever else it may contain does not natu- rally belong to it. It is liquid at all ordinary temperatures, but becomes, under average pressure, solid (ice] at and under 32 Fahr., and aeri- form (steam) at and above 212 Fahr. A cubic inch weighs about 250 grains ; a cubic foot about 63 Ibs. avoirdupois, or about 1,000 ozs. It is taken as a convenient unit or standard for the specific gravity of solid and liquid bodies generally; thus, water being I, and lead ir, means that lead is 1 1 times as heavy as an equal bulk of water; and thus 1 1 is said to be the specific gravity of lead. Water is with great diffi- culty compressible, and conducts heat slowly. It is affected in colour, taste, odour, and other qualities by the differences which mark it as ob- tained from rain, dew, springs, rivers, wells, lakes, marshes, and seas; and especially such kinds as are called mineral waters. Sea- water contains something like 5 per cent, of salts of soda, potash, magnesia, and lime especially chloride of sodium, which gives it its characteristic salt taste. Water Colours. Under COLOUR WAT 424 WAT MAKING it is briefly mentioned that a vast body of substances (separately noticed in different parts f the work) are employed in making colours for artists, house-painters, paper-stainers, dyers, calico-printers, &c. It may here be added that water colours comprise a larger se- lection from the organic kingdom, a smaller from the mineral kingdom, than oil colours. A more thorough grinding and mixing of the ingre- dients are necessary for water colours than for gum colours or oil colours, especially for miniature-painting and map-colouring. The advances re- cently made in chemistry have added greatly to the brilliancy of the co- lours available, and to the cheapness of the boxes of colours that can now be made. Water Engine, not much used in England, is an apparatus em- ployed in some of the continental mines for moving machinery by means of a descending column of water. There must always be a great descent, easily and cheaply obtained, to render the system worth adopting. There is a vertical cylinder, with a piston working up and down it, and two horizontal pipes near the bottom. Water, rushing by a descending co- lumn, enters the cylinder at one of the pipes, and drives up the piston, other arrangements then allow this water to escape by the other pipe, whereupon the external pressure of the atmosphere drives the piston down again. This reciprocating movement of the piston through the medium of the piston-rod be- comes a source of power for other machinery. Such a water-engine is single action. In the double-action machine the piston is pressed down as well as up by the water. This effect is produced by closing the top of the cylinder, and providing ad- ditional lateral pipes and valves, which reverse the direction of pres- sure upon the piston by self-regu- lating movements. Some of these engines, in continental mines, are worked by descending columns of water as much as 200 feet in height. Water Freshening-. The supply of water to ships at sea is an im- portant and difficult duty. If suffi- cient be taken out for a long voyage, the tanks and casks must necessarily occupy a very considerable space ; while, on the other hand, if a supply on the way be depended on, many contingencies may interfere with its success. Hence numerous plans have been proposed for utilising the water of the sea by depriving it of its soda and potash salts, and rendering it available for cooking, drinking, and washing. It is known that when water is converted into steam, very little more than the watery particles themselves ascend, leaving all salts and impurities in the vessel. This separation is the basis of most of the plans actually adopted. Grant, M 'Bride, Murdoch, Ericsson, Grave- ley, Normandy, and other inventors, have contrived apparatus which will distil the water ; and the endeavour is to burn as little fuel as possible in effecting this. In some of the inventions the fire which cooks the ship's provisions is applied at the same time to distil the water; and, indeed, invention has so far pro- ceeded that the waste heat from the cooking stoves is thus utilised. The water, as it ascends in vapour, leaves behind it in the vessel various solid substances, such as salt, clay, sand, carbon, alkalies, &c. ; and the vari- ous pipes of the apparatus must be so arranged that these impurities may find an appropriate outlet. As water is very vapid and insipid for drinking when distilled, means are usually adopted for aerating it ; that is, driving fresh atmospheric air into it. In Grant's apparatus this is effected by agitation of the water in the vessel ; in M'Bride's a kind of blowing machine drives a current of air into the water ; in Miirdoch's, a suction apparatus draws air as well WAT 425 WAT as steam into the condenser ; and in all the other varieties the same effect is sought to be attained by various means. There can be no doubt of the value of these con- trivances ; and it is becoming more and more usual to provide ships with such apparatus. In the war with Russia, in 1854 and 1855, the Bri- tish fleets in the Baltic and Black Seas were well supplied with water- freshening appliances. During the Abyssinian Expedition, in 1867-8, about ninety transports were sent with men and stores to the African coast; and of these about eighty were thus provided. Some of the ships ranged as low as 30 gallons, some as high as 10,000 gallons, of salt water distilled into fresh daily ; while one ship, the Semiramis, was permanently moored in Annesley Bay as a water-ship. It is almost impossible to calculate the amount of service which was in this way rendered to the troops engaged in the expedition. Water Glass is one of the names given to a liquid which dries to a peculiar vitrified surface. Itis usually a silicate either of soda or potash. One mode of making it is to mix sand and carbonate of potash, and bake them in a reverberatory fur- nace. This is called the dry way. In another, the wet way, chalk flints are broken and calcined, added to a solution of caustic potash or soda, and exposed for a time to intense heat. The water-glass thus made is one of the substances employed to prevent the decay of stone, and also in soap-making. It is employed to mix with fresco colours for a parti- cular kind of painting, such ,as was adopted by Maclise in his large "water-glass frescoes " in the Houses of Parliament. It is found useful as a mordant in calico-printing. When used in painting, some artists make it the liquid vehicle of the paint itself; while others mix the paint with water, and apply the so- lution as a liquid wash a few hours aftenvards. Potash is the alkali pre- ferred by painters, soda by calico- printers, &c. Water Meter. In any perfect system of water-supply to houses, it is necessary to adopt some means of measuring the quantity each house consumes. Hitherto very little has been done in this direction. An apparatus on the rain-gauge plan might be used if the water is mea- sured in a reservoir or large cistern belonging to each house ; but a better plan would be to measure the efflux directly from the pipes, under whatever pressure the service may be acting. In most contrivances for this purpose hitherto tried, the measurement is made by the revo- lution of a fan, like a screw-propeller, fixed within the pipe, and driven round by the water in flowing out. Water Power. Examples of the use of water as a source of power are given under HYDRAULIC CRANE ; HYDRAULIC MACHINERY ; HYDRAULIC PRESS; HYDRAULIC RAM. Waterproofing:. The largely- increased use of india-rubber in no way shows itself more apparent than in the manufacture of water- proof garments and cloth textile goods in which the meshes are closed against the passage of water. Many solutions and compositions have been employed for this pur- pose. Petroleum, whiting, and water; alum, white-lead, and water; the same ingredients with acetic acid added ; tar, as for tarpaulins ; oil, as for oil-skin ; a mixture of boiled oil, pipeclay, burnt umber, white-lead, and pumice-stone all have been employed. Some special kinds have been applied to leather rather than cloth, such as a mixture of linseed oil, suet, bees'-wax, and resin; a mixture of linseed oil, resin, white vitriol, turps, and saw- dust ; a mixture of bees'-wax. Bur- gundy pitch, turpentine, and linseed WAT 426 WAX oil ; and others in which tallow is a principal ingredient. But the chief waterproofing agent at pre- sent is india-rubber. Cloth satu- rated with this gum is extensively used for outer garments, life jackets and belts, life-buoys, collapsible boats, beds, hammocks, mattresses, cushions, pillars, umbrella tents, portable bottles, shoes, and count- less other articles. Waters, Mineral. (See MINE- RAL WATERS.) Water Wheels. Most kinds of water-wheels are contrivances for working machinery by the descent of a large body of water from a small height, whereas a water- engine requires the descent to be from a considerable height. In most cases a stream, made artifi- cially to descend at a certain angle (not by a vertical fall), is the source of power ; and there are four arrange- ments of wheel by which the power is rendered available. (I.) Under- shot Wheel. This is a vertical wheel, having a number of boards fixed radially, and at equal distances around its circumference. A stream of water is made to descend at such an angle as to catch against these boards at a considerable distance below the axis or centre of the wheel ; the water presses against the boards before it can escape, thereby causing the wheel to rotate. (2.) Overshot Wheel. Here the boards are superseded by buckets, boxes, . or troughs. The water attacks the wheel nearly at the highest part, fills some of the buckets, makes one half of the wheel heavier than the other, and thus causes it to rotate, each bucket being emptied again as it approaches the lower part of its revolving course. (3.) Breast Wheel. Here the wheel, like the overshot, has boards instead of buckets. The stream is made to descend one quadrant of a circle, concentric with the whole. The water attacks the wheel nearly midway of its height, and fills the cellular spaces formed by the mill-race, the edge of the wheel, and the boards ; the wheel rotates by the preponderant weight of the side thus loaded. (4.) Hori- zontal Wheel. This, as its name imports, is horizontal, rotating on a vertical axis. The boards are dia- gonal, a descending stream of water attacks these diagonally, and the resulting effect is that the wheel is caused to rotate. In all these cases, when the wheel once rotates, it may be utilised as a source of power for grinding corn or turning machinery of various kinds. Each form of water-wheel is best suited for some particular circumstances or condi- tions, the horizontal being prefer- able where a vertical axis of motion is required. Water Works. As a large sub- ject of civil engineering, water supply does not come within the scope of this work. The practical means adopted are, however, to some extent noticed under PUMP, TUBE WELL, and WELLS. Wax. This remarkable sub- stance is both of animal and vege- table origin. Wax is found in plants, and naturalists formerly held an opinion that bees find the wax ready made in the flowers on which they light ; but the opinion now is, that the insects elaborate it within their own bodies, out of the honey imbibed from the flower. The way in which the bees build up the honeycomb with the wax thus obtained is well known as one of the most marvellous examples of instinct presented in the whole range of nature. When the wax of the honeycomb is collected by man for manufacturing purposes, the honey is drained or pressed out of it ; the comb is boiled in water, melted, strained through hair-bags, and purified or refined in various ways. Bees'-wax is yellow during all these processes ; to become WAX 427 WEA white wax it requires bleaching. The most effective way of doing this is by exposing the wax for a long time to the combined action of light, air, and moisture ; the pro- cess may be quickened by the use of chlorine and other agents, but the result is not quite so good. Purified wax is a little lighter than water, is soft enough to be kneaded at 85 Fahr., and melts at 150. The wax obtained from various kinds of trees, such as the myrtle, the palm, the sumach, the sugar- cane, and the cork tree, is similar in general properties to that obtained from bees. A large quantity of wax was formerly used in making the candles for Roman Catholic churches and chapels ; but stearine and other substances have in late years been to some extent sub- stituted for it. Sealing-wax is one of the principal articles now made of wax (see SEALING WAX) ; and various polishes and varnishes also absorb a large quantity of it. Much of the wax brought to market, espe- cially if offered at a low price, is adulterated earth, pea-meal, and resin being added to yellow wax ; oxide of lead, tallow, and starch to white wax. Wax Flowers. (See FLOWERS, ARTIFICIAL.) Wax Modelling-. The degree of softness possessed by most kinds of wax greatly facilitates the use of this substance in various processes of modelling. The ancients were acquainted with the arts of model- ling, not only small busts and statuettes, but also moulds for bronze casts, in wax. They also practised a method of making a model in wax, coating it with soft clay, drying the clay, melting out the wax, pouring molten metal into the cavity thus produced, and finally removing the clay. The metal thus took the precise form of the original wax model. In later ages it became more customary to leave the wax model untouched, as a piece of original wax ; sculpture and many beautiful works of this kind have been executed. Weaving-, the art of interlacing threads so as to form a web or cloth, takes rank among the very oldest of the arts. Primitive nations under- stood it in the early Biblical times ; and rude nations understand it at the present day. It matters not whether the material be rush, grass, straw, wool, silk, cotton, flax, jute, or hemp ; the strings or strips can always be so interlaced as to form a fabric or textile web. It may be netting, or knitting, or plaiting ; but the most generally useful mode is weaving. Here some of the threads are ranged lengthwise of the cloth ; these are called -warp, woof, chain, caine, twist, or organzine ; others, ranged breadthwise, are the weft, shoot, or tram ; but the usual terms employed are warp and weft ; and weaving consists in interlacing the weft among the warp by succes- sively passing under and over them. How this is effected has been ex- plained under LOOM, HAND and MACHINE. In plain weaving, the weft passes over and under the warp in regular alternation. In shot weaving, the warp is of one colour and the weft of another. In stripe weaving, the warp threads are of two or more different colours. In check weaving, both the warp and the weft are parti-coloured, one set of stripes crossing another. In twill weaving, the weft leaps over or under several warp threads at once. (See TWILL.) In pile weav- ing, a kind of surface of cut ends of threads is left, sheared level and smooth. (See CARPET MANUFAC- TURE ; FUSTIAN; VELVET.) In figure weaving, devices are worked in among the warp and weft, either by the same or by other threads. (See LOOM, MACHINE ; JACQUARD MACHINE, for the mode of effect- ing this.)' In mesh weaving, spaces WED 428 WEI or meshes are formed between the threads, giving rise to that infinite variety of beautiful results noticed under BOBBIN NET and LACE. Loop weaving, a name that may be given to a peculiar mode of twist- ing threads around each other, is illustrated in FRAMEWORK KNIT- TING and HOSIERY MANUFAC- TURE. In the processes of ordinary weaving, the spun yarn for the warp is first warped (see WARP, WARP- ING), or grouped together in a cer- tain number of threads ; then beamed or wound upon a yarn beam ; then coated with a paste or size to smooth the fibres (see DRESSING) ; then drawn in, or passed through the eyes of the healds, each thread separately through one eye ; then passed through the dents of the reed ; and so finally adjusted to the loom. The winding of the weft thread upon the pieces in the shut- tle being completed, the weaving begins. "Wedg-wood Ware. Josiah Wedgwood, who was to English pottery what Richard Arkwright was to cotton-spinning, began those experiments about the year 1760, which led to the firm establishment of many beautiful varieties of this manufacture in Staffordshire. Tech- nically, Wedgwood ware is the name of one particular kind of goods in- troduced by him; but in reality there are several quite as closely associated with his name and his labours, (i.) Queen's ware, ox cream- coloured ware, patronised by Queen Charlotte, was made by combining metallic oxides with pipe-clay and sand ; it laid the foundation of his fortune. (2.) Tcrra-cotta, a ware which imitated porphyry, granite, and other kinds of hard stone. (3.) Basalt, a black ware nearly as hard as flint. (4.) Porcelain biscuit, differ- ing Irom basalt chiefly in being white in colour. (5.) Bamboo ware, a kind of cane-coloured biscuit. (6.) Jasper, a very delicate white bis- cuit, suitable for cameos and sta- tuettes. Taking the middle path between opaque pottery and trans- lucent porcelain, Wedgwood pro- duced many exquisite works com- bining the characteristics of both of which his imitations of the Port- land Vase are world-renowned. (For all practical processes see PORCE- LAIN and POTTERY.; "Weft. This is one of many names for the cross threads in woven goods. (See WEAVING.) Weig-hing Machine, as distin- guished from balances, scales, steel- yards, &c., is larger in size, and in- tended to weigh heavier masses. On turnpike roads there is a rule that the weight of a loaded waggon must not exceed a certain ratio to the breadth of the wheel, as a pre- caution against wearing down the road material too rapidly. Weigh- ing machines are placed at certain localities to test this matter, the whole waggon and its contents being weighed at once. The waggon is drawn upon a platform which is over a cavity in the roadway ; the platform is supported only on four points, which points are the ends of four levers ; these levers act upon some kind of index or tell-tale. When the waggon is on the plat- form, the latter sinks a little ; and the amount of this sinking is made, through the action of the levers, to work a graduated scale which shows the total weight of waggon and load. This form of weighing ma- chine is mostly confined to toll- gates, but it is also used in other ways. The machines for weighing goods at railway and canal stations and depots are of intermediate character between the common balance and the weighing machine, combining something of the action of both. The French have an in- genious weighing machine by M. Beranger, called a peso-compteur, which registers on a sheet of paper the weight of the article weighed. WEI 429 WEL Weights and Measures. Under AVOIRDUPOIS and TROY WEIGHT the chief modes of dividing the English pound are described. We need here only add that the stand- ard of English measures of length is the yard, of which very carefully- prepared models or specimens are kept under official guardianship, and the length of which bears a definite relation to that of a seconds pendulum. The standard measure of capacity is the imperial gallon, containing 10 Ibs. avoirdupois of distilled water at a medium tem- perature and pressure. The stand- ard peck, bushel, and quarter are multiples of the gallon ; and the standard quart, pint, and gill sub- multiples ; but in practice the stand- ards are often widely departed from, as in the familiar instance of a so- called " pint bottle of ale." Any ordinary table of weights and mea- sures will give further information on these points. Weld consists of the dried stem and leaves of the Reseda luteola, a plant growing in various parts of Europe. It is gathered when in seed, and constitutes a useful dye drug for various tints of yellow. Welding- is one of the many modes of uniting two pieces of metal. Two surfaces of iron, raised to a red heat, may be welded together by hammering, with a little sand to form a flux, which will prevent the metal from oxidising during the process. Two iron bars may be welded end to end by making a sort of rudimentary joint or scarping in the first instance. If well done, the place of union is as strong as any other part of the compound bar. Iron is one of the few metals which possess this valuable property. Many important articles of manufacture depend in- timately on this welding property of iron. Horn, tortoiseshell, and a few other substances can be subjected to a similar process of welding. Wells, considered as part of the great subject of water supply, be- long to civil engineering; but a little may be said here concerning the mechanical means employed. Wells, until modern times, were simply circular pits sunk into the ground, and carried down till water was reached. The sides of the ver- tical shaft were either lined or not, according to the hardness of the earth or rock. Digging, ladders, hauling ropes, and a windlass are the chief agencies employed in merely sinking the well itself. In lining or steining wells, slate, timber, or mortar is sometimes employed to make out the brickwork ; but in the best works only good bricks and durable cement are used. Puddling with rammed clay, or still more ad- vantageously, concrete, is introduced behind the bricks when the soil is wet or loose. Sometimes the soil is so fully saturated with land-springs that an iron cylinder is used at cer- tain parts, to keep out the water. The adoption of these open wells, however, has been very much less- ened since the introduction of Ar- tesian wells, so named from being first used at Artois, in France. An Artesian well is not a large pit or shaft dug, but a small tube bored ; the former is lined with brickwork, the latter only by a metal tube. Wells of somewhat similar construc- tion were not quite unknown to the ancients ; but it is only in recent times that the method has developed itself into a system. To make an Artesian well successful, there must not only be water underneath, but a connection between that water and springs at a higher source, so as (o obtain a pressure or head. When a proper point is selected, a hole is pierced vertically downwards by means of boring tools affixed to boring rods, and the rods worked by mechanical or other power. A metal tube is slid down as fast as the bore-hole is made, and then the WES 430 WHE well is virtually complete. How far the work will have to be carried before a good supply of water is reached is the great question at issue ; and a second question is, will the water spontaneously rise quite up to the surface ? In some Arte- sian wells the water not only ascends to the top, but constantly flows over; whereas in others it does not reach the top, and has to be pumped up by ordinary means. In 1841 an Artesian well at Grenelle, in France, was finished, to the enormous depth of i, 800 feet ; the bore was for some depth 12 inches in diameter, then 9 inches, and so lessened to 6 inches. An abundant supply of water re- warded the Government for seven years of anxiety and a large ex- penditure in money. Several others of great depth have been bored in England and on the Continent. The supply of water in some wells fluc- tuates greatly from time to time ; and it is often found that an extra draught at one well affects the sup- ply of others in the neighbourhood. Westminster Clock. As the clock at the new Houses of Parlia- ment is the largest and finest in the world, we will give a few figures relating to its dimensions. The going part is wound up once a week, and the striking part at about the same interval. The weights that give motion to the whole machine hang down a shaft 160 feet deep. The pendulum is 15 feet long, and weighs 680 Ibs. ; for compensation during changes of temperature, there is a zinc inner tube to an iron outer one ; it swings in a vibrating arc of onlyi4inches; and ?. weight of I oz., applied at a particular part, will alter the going of the clock one second per day. There are four dials on the four sides of the clock- tower ; these dials are 22| feet diameter, and the iron framework of each weighs 4 tons. The hour figures are 2 feet high and 6 feet apart; the minute marks are 14 inches apart, and the minute hand makes a sudden and visible leap of 7 inches every half-minute. The minute hand is 16 feet long, the hour hand 9 feet; and the two together weigh 2 cwt. Whalebone is a kind of horny plate, with a fringe-like edge, serv- ing as a substitute for teeth in some kinds of whale. Its remarkable properties render it very useful in the arts. When softened by boiling, it may readily be cut up into hairs or bristles for brushes, stretchers for umbrellas, stiffeners for stays, plaits for whips, telescope and opera-glass covers, thin shavings for bonnets and artificial flowers, and numerous other purposes. Whalebone may be polished by the application of emery powder, rotten-stone, &c. Whale Oil. The oil for which whales are chiefly captured is con- tained in the blubber, a kind of fat that envelops the animal between the skin and the muscles. The thickness of the layer varies from 6 or 8 to 1 8 or 20 inches. The whale-fishers in old times used to melt down the blubber on the shores of Greenland or elsewhere, and bring home the oil in casks ; but now it is more customary to bring home the blubber itself. When the animal is dead, the blubber is cut off and separated into pieces, which are packed in casks. Reaching Hull, Aberdeen, or some other centre of the whale-oil trade, the blubber is emptied from the casks into a large receiver, and then undergoes boiling and purifying, until as much oil is obtained from it as possible. Sometimes 100 tuns of oil are ob- tained from the blubber of a full- grown whale. (See also SPERMA- CETI and SPERM OIL.) Wheat. For some of the purposes to which this invaluable grain is ap- plied, see BREAD MAKING, DISTIL- LING, FLOUR MILL, STARCH, &c. Wheel Carriages. If we sup- pose less elegance and more strength WHE 431 WHI to be employed, COACH MAKING will afford some idea of the processes called for in making all the nume- rous varieties of wheel carriage. Wheel Making-. An ordinary coach wheel is so contrived as to combine lightness and strength in a remarkable degree. The nave is usually elm, the spokes oak, and the felloes ash. The block of elm to form the nave, when properly shaped in the lathe, has the mortise-holes carefully chiselled out, to form re- ceptacles for the ends of the spokes. This requires great accuracy of hand and eye, seeing that the number, distance, size, and shape of the holes must all bear strict relation to the form which the wheel is to assume : to insure the dishing of the wheel is one among the chief of these niceties. The spokes are shaped almost entirely by hand, with the aid of a spokeshave. For average English coaches, the front wheels are 40 to 44 inches diameter, with twelve spokes ; the hind wheels 50 to 56 inches diameter, with fourteen spokes. One end of each spoke is formed into a tenon, to fit into a mortise in the nave. When the spokes have been driven into their places by mallet-blows, the rim is put on. This consists of several segments called felloes, all adjusted accurately one to another, and pierced with holes to fix them upon the spokes. The tire, or iron hoop, is shrunk on hot ; that is, made to bind tightly around the rim by shrinking while cooling. Whetstone. (See HONE, &c.) Whiskey is a spirit not so much sweetened or flavoured as gin. It may be made from grain, from malt, or from a mixture of both. The large stills mostly distil whiskey from grain, smaller stills from malt. The ordinary whiskey sold in England is mostly without any characteristic flavour ; it is strong spirit, and nothing more ; but the more special kinds, Scotch and Irish, are scented ' with certain volatile products which arise during the fermentation and distillation, and some of them with a peat-reek or smoke flavour. These special flavours and fragrances are more associated with malt than with grain whiskey that is, grain malted rather than unmalted. (See further under DISTILLING ; MALT and MALTING ; SPIRIT, SPIRITS.) White-leadis one of the most im- portant substances known in house- painting, and the object of large manufacturing operations at New- castle and other places. It is car- bonate of lead, and is prepared from metallic lead. Pieces of cast-lead are placed in earthen pots with a little acetic acid. The pots are ar- ranged in rows in a brick chamber, embedded in spent tan ; loose slates, tiles, or boards are placed upon the pots, to support another row ; and so on, until the chamber is filled with successive tiers of similar pots, to the extent sometimes of 10,000 or 12,000 pots in all, containing 50 to 60 tons of lead. All the pots of every tier are embedded in tan, or (in France) in stable manure. When the chamber is closed in, the tan ferments ; the temperature rises to 150 Fahr. ; the acetic acid slowly volatilises ; and the vapour of this acid, mixing with the oxygen of the air, attacks the lead, and gives rise to many chemical changes. There is first formed an oxide of lead, then a subacetate, and then a carbonate. The tan loses its fermenting power in five or six weeks ; the stack or heap is opened, and the pieces of lead are removed from the pots ; they still retain their shape, but are increased in bulk, and are through most of their substance changed into dense white carbonate. The carbonate is crushed and broken into powder by passing the plates through rollers ; it is ground up with water, and reduced by roasting and drying to a fine white impal- pable powder, which constitutes dry WHI 432 WHI -ivhite*iead. When this substance is to be used for house-painting, it is mixed in a vat with linseed oil, by means of a mechanical stirrer, to the consistence of a stiff paste; 8 Ibs. of oil being added to I cwt. of white-lead. It is finally ground under a millstone and packed in casks. Other modes of making white-lead are adopted, in which the carbonate is obtained from different salts of the metal; but the one we have described is the process mostly adopted for large manufacturing operations. White- lead, in its grinding and using, is very injurious to the health of the workmen ; and many attempts have been made to introduce zinc white instead, but without much success. Various kinds of white powder or pigment, known as ceruse, Clichy white, Venice white, Hamburg white, Dutch white, Kremnitz -white, and silver white, are either veiy pure white-lead, or a combination of it with sulphate of baryta. White Metal. There are arti- ficially-prepared white metals now used in enormous quantity at Bir- mingham and Sheffield as substi- tutes for silver, sometimes for the entire bulk of the article made, sometimes as a backing for a founda- tion on which real silver is to rest. German silver is made of copper 40, nickel 32, zinc 25, and lead 3. But, in truth, there are many different proportions of those metals, because nickel has a remarkable property of imparting whiteness to copper and other metals. Sometimes a little iron is used instead of, or in addition to, the lead, according as the alloy is required to be hard, or bumished, or soldered. Albata, British plate, Electrum, Nickel silver, Packfong, and 'Tutenag, are all names for white alloys made of some such metals as German silver copper being the chief constituent, and nickel and zinc the next two in im- portance. As nickel is the most expensive of the metals emoloyed, the cheaper kinds of silver substitute have as little of it as possible. Queen's metal consists of tin 9, antimony i, bismuth I, lead I. These white alloys, taking a more or less brilliant polish, are largely used as substitutes for real silver in table plate, harness, and furniture ornaments, spectacle and eye-glass frames, &c. There is one of them which, from the peculiar way of working it, is described separately. (See BRITANNIA METAL.) White-wash, is simply water in which slaked lime is dissolved. The solidity of the white produced depends on the proportion of lime used ; and when employed as a white coating for walls and ceilings (not merely a disinfectant), a little melted size is added. Whiting, used in making putty and other substances employed in the arts, consists of chalk ground under water, and washed to remove sand, &c. It is a remarkably soft and smooth substance, almost wholly free from gritty particles. Whitworth G-un. The dif- ference between Mr. Whitworth 1 s hexagonal bore, and the various systems of rifling adopted by other inventors, has been noticed under ARMSTRONG GUN; CANNON FOUNDING ; RIFLE, RIFLING ; SMALL ARMS, &c. Whitworth guns are still under trial, to test their various qualities ; but their great costliness is one reason why they have not yet taken their place among regular ordnance for service. The greatest range -ever reached by a gun was with one on Mr. Whit- worth's construction. Up to very recently, that honour was given to a Lynall Thomas gun of 7-inch bore, which threw a shot of 175 Ibs. to the amazing distance of 10,075 yards, or nearly 5^ miles. A Whit- worth gun excelled this in 1868, effecting a range only a few yards short of 6 miles. Whitworth Scholarships. WIC 433 WIN These noble incentives to scientific and technological study are briefly noticed under INDUSTRIAL SCHO- LARSHIPS. The practical develop- ment of the plan may in some few particulars be modified, but its general character is to be maintained. The candidates for the scholarships must be ypung Englishmen under twenty-six years of age, but there is no other limitation ; for it is the wish of the liberal donor that no kind of favouritism shall be allowed to interfere with the wide generality of the scheme. The young candi- dates must know something of science, something of mechanical philosophy, something of the work- shop and its tools. Competition is to take place once a year between as many candidates as are qualified to appear. Marks are to be as- signed for each among many kinds of efficiency ; and the number of marks in each will denote the de- gree of this efficiency. Wick. For the modes in which the cotton wicks of dip and mould candles are usually immersed in the tallow or other composition see CANDLE MANUFACTURE. Wig- Making 1 . The wig or peruke worn by the ancients is sup- posed to have been made of painted hairs glued together. A costly kind was powdered with gold, pre- viously wetted with perfumed oil to insure adhesion. Wigs, or false heads of hair, began to be generally worn by the courtiers in England about the time of Stephen, seven centuries ago. The " Ramilies' tail " of George I.'s time was a tail plaited to the wig; the regular " pig -tail" did not come into vogue till the next reign. There is a good deal of small finger- work in the insertion of the hairs of a wig into the foundation ; but a French- man has invented a kind of small loom for weaving wigs. Winch. A very convenient steam-winch has been invented, pri- marily to facilitate the receiving and discharging of cargoes ; but it has also been found available, in the larger kinds of merchant ships, for working the yards and sails, anchors and cables, and other heavy parts of a ship's fittings. Wincing 1 Machine. In dyeing, where the cloth has to be repeatedly dipped into liquids, there is over some of the vats an apparatus called a wincing machine. This is a kind of reel or skeleton frame, rotating on a horizontal axis. The cloth passes over this frame ; and accord- ing as the apparatus is rotated to the right or the left, the cloth dips into one or other of the two vats, or into two compartments of the same vat. Wind Furnace. This kind of furnace, used in making cast-steel, and in some other special metal- lurgic processes, is calculated to produce a very intense heat. The furnace, a square chamber of small size, is lined with a cement or clay that will resist the strongest heat. The fuel is well-made coke in small pieces. The air for feeding the fire is admitted under the grate, in such a way as to produce in the chamber a temperature so enormously high as to convert steel into a thoroughly liquid state. Winding 1 Machine. (See under THREAD, WEAVING, and the chief kinds of textile materials.) Windlass differs principally from a capstan in having the barrel or centre horizontal instead of vertical. It is worked by bars temporarily inserted as levers in holes in the barrel or head, as in a capstan, but with a necessary change in the direc- tion of movement. Windmill. Although the vast extension in the use of the steam- engine has lessened the employment of windmills, they will always be advantageous under certain circum- stances, especially when fuel is dear or difficult to obtain. A wind- mill consists essentially of a wooden F F WIN 434 WIN structure that will rotate on a verti- cal axis, and having wings or vanes that will revolve in common on a nearly horizontal axis. The wind, acting on the vanes, causes them to rotate ; and this rotation can easily be made to work millstones or any other rotating mechanism ; while the movement of the whole build- ing round its axis enables the vanes to be presented at the proper angle to receive the impact of the wind. Each vane is about 40 feet long, and consists of a sail-frame or skeleton with stretchers and strengthened of wood, and a covering of sail- cloth. In some windmills the vanes are adjusted to meet the wind by ropes and a windlass below ; but in the better kind a sort of weather- cock on a subsidiary vane is so ad- justed as to allow the wind to do the work. Numerous mechanical con- trivances are adopted to check the velocity of the vanes, stop them alto- gether, &c. ; but the principle of all windmills is really very simple. In some special circumstances hori- zontal windmills are used, the vanes revolving around a vertical axis. "Wine, British, is a general name for such wines, or substitutes for wine, as can be made in this country, where the grape does not ripen in the open air to such a degree as to form true wine. Nearly all kinds of fruits, and many kinds of roots, flowers, &c., may be used for this purpose ; since, whatever the flavour may be, there is always a good deal of sweetening with sugar. In fact, British wines are known to the Excise as sweets. In making raisin wine (selected as a type of the class), the raisins, which are really grapes dried in the country of their growth, are steeped in water to soften and swell ; and by means of repeated pressing, the raisins are made to give up to the water all their juice or soluble extract. To obtain the last remaining portion of this extract, the force of a powerful hydraulic press is employed. The juice is slightly fermented with a little yeast or leaven ; then transferred ' into large vats ; then racked and clarified in various ways ; then fined with isinglass and sweetened with sugar ; and finally casked or bottled for sale. "Wine Making 1 , as a chemical manufacture, belongs to. the same general group as brewing, distilling, and vinegar-making. In all of them vegetable substances undergo fer- mentation, whatever other process may supplement this. As a rule or standard, the fermented juice of the grape is the only true wine ; but, chemically speaking, the juice of any other fruit equally deserves the same name ; while parsnip, cowslip, beet-root, ginger, and a large number of other roots, flowers, stalks, leaves, &c., yield juices which may also be fermented into a kind of wine. The wine of the grape derives its flavour from a large number of circumstances the quality of the soil, the average summer tempera- ture, the humidity or dryness of the climate, the clearness of the sky, the nature of the seed, and the processes of vintage. Port, Sherry, Lisbon, Cape, Malmsey, Madeira, Marsala, Bucellas, Burgundy, Frontignac, Bordeaux, Claret, Tent, Mountain, Muscadine, Champagne, Hock, ChaHis, Moselle, Constantia, Beau- jolais, Tokay, Rhenish wines, Greek wines, Sicilian wines, Hungarian wines, Australian wines all are alike the fermented juice of the grape, how striking soever maybe the differ- ences between them. Insome grapes sugar is rich, producing luscious fruity wines ; in others, acids and essences are rich, giving rise to minute variations in flavour. So numerous are the circumstances which affect the making of wine, that a good vintage year may be followed by a very bad one, or a good sherry vintage be coincident with a bad claret vintage, and yet the cause of the diversity be wholly WIN 435 WIR undiscoverable. The port that was made in certain years commands a very high price, on account of its exceptionally good quality; grape growers and wine-makers being ignorant how to insure an equally good wine in other years. Very old port was sold at Birmingham in 1868, at /5 per bottle; while claret of the vintage 1811 was sold at Paris in 1868 for^io per bottle In fact, vintages are as uncertain as hop-growing. There are as many as 600 or 700 kinds of vine, the grape of every one of which will yield wine. The juice of ripe grapes contains sugar, gum, gluten, several acids, several salts, and colouring matters ; it is no cause for wonder, therefore, that the flavour of the wine should vary almost infinitely according to variations in these constituents. The colour of wine depends almost wholly on that of the skins or husks, which are usually fermented at the same time as the juices. Air has sometimes the effect of darkening the colour of wine, especially white Rhenish and Bordeaux wines. The quality and age of the wood (usually oak) of which a cask is made will affect not only the colour, but the quality of the wine. The bouquet, or combined odour and flavour, appears to result from a peculiar volatile acid which is generated during the fermentation ; where an artificial bouquet is imparted to an inferior wine by means of flower and herb essences, this must be re- garded as a kind of sophistication. The usual mode of making claret will sufficiently illustrate vintage operations. The grapes, deprived of the rotten and unripe branches, are put into a vat to the depth of 15 or 20 inches ; 2 gallons of brandy are poured on them ; then another layer of grapes ; then more brandy ; and so on, until the cask is full, to the quantity of 30 to 36 tuns. This, called the cuve-mere or mother-vat, is covered up closely, and allowed to ferment for three or four weeks. While this is going on, the main portion of the wine is being made by a separate process. The grapes, thrown into large cisterns, are trod- den by the naked feet of men ; the juice runs out through an aperture into tubs ; the juice and the skins together are thrown into great vats to ferment, which they are allowed to do for ten or twelve days. The wine thus produced is mixed with a certain proportion from the cu-ve- mere ; and very careful processes of examining, racking, fining, &c., con- tinued during many months, finish the manufacture of the choice beve- rage. _ About 15,400,003 gallons of foreign wine were imported in 1867. As to quality, this comprised 6,700,000 gallons red, and 8,700,000 gallons white. As to country of growth, 7,300,000 Spain ; 2,700,000 Portugal; 3,800,000 France ; and the rest miscellaneous. Winnowing Machine. The cleansing of corn from husk and chaff, after threshing, is now effected in a very complete way. In one apparatus, Hornby's winnowing machine, there is a spiked roller working through a grating, and forming a sort of hopper. The corn, in the rough pulsy state as it comes r rom the threshing machine, is put nto the hopper, and the whole mass Decomes separated into "best corn," 'good tail," "tail," "whites," screenings," and "chaff," at the rate of 15 quarters per hour. "Wire Drawing-. Wire is a result of the ductility of metals >rought into action in a peculiar way. The ancients made their wire by hammering metal into thin sheets, cutting it up into strips, and ham- mering the strips into wires. The modern method is far more rapid tnd effective, the metal being haped into rods by being drawn in a red-hot state) between grooved oilers, and the rods reduced to ire by being drawn (in a cold state) WIR 456 WIR through holes in a plate of some harder metal. Most rods for wire are about -| inch thick, all the sub- sequent reduction being made by the wire-drawer. The draw-plates are made of hard steel, and are pierced with holes varying by al- most insensible degrees in diameter ; these holes are mostly round, and are made with very scrupulous care. The rods are drawn through a great number of holes in succession, so as to reduce their thickness gradually. Much mechanical force is required to pull the wire through. This is effected by the aid of a draw-bench, drawing-block, revolving shaft, bevel wheels, forceps, toothed rack, &c. Steam power or water power is em- ployed to rotate the shaft, which is the source of all the other move- ments. The wire requires frequent annealing, on account of becoming so much hardened by the compres- sion ; and a pickling in dilute acid is necessary to remove the film of oxide formed during the annealing. In some cases a lubricating substance is used to facilitate the passage of the wire through the holes in the draw-plate. Most wire is round, being drawn through circular holes ; but some kinds are made oval, half round, square, angular, &c., for spe- cial purposes. A few of the deli- cate kinds of wire, such as that for the pendulum springs of chronome- ters, are drawn through holes pierced in small pieces of ruby ; steel not being hard enough for the purpose. Some of the finest wire used in the arts is that which is woven to form the wire gauze of safety lamps ; this gauze often has 120 wires each way in an inch, or 14,400 meshes in a square inch. Wire Hopes. The material of which ropes shall be formed is a matter for much consideration in shipping, owing to the large quan- tity required. It used to be con- sidered, in the old days of sailing ships, before the employment of steamers and iron-dads, that a first- rate man- of- war carried no less than 43 miles of cordage, adding up all from the smallest rope to the thick- est cable ; and as, one with another, these several kinds averaged 2 tons per mile, the weight became some- what formidable. The largest of the cables, 8 inches diameter and 25 in circumference, had no less than 360 yarns in every strand (see ROPE MAKING) ; and, therefore, the weight of hemp consumed in a given length of cable was very great. The price of the fibre being often enormously high in war-time, there was every inducement to substitute iron for hemp, if it could be accomplished. The larger substitutes are described elsewhere (see CABLE, CHAIN) ; we here treat of wire ropes. They were first used in some German mines, about the year 1830. They soon became adopted in England ; and patents for various modes of making them were obtained by Smith, Newall, Glass and Elliott, and other inventors. Sometimes straight, un- twisted wires are bound together at intervals ; sometimes wires are twisted into strands, and strands into larger ropes, on the same principle as hempen ropes, though not with so hard a twist ; and sometimes flat ropes are made by joining wire ropes side by side with some kind of hempen or canvas connection. The chief uses of iron-wire ropes are for ships' rigging, mines, wire suspen- sion bridges, and submarine electric cables. The latter is now a very important application ; the two At- lantic cables, laid down in 1865 and 1866 respectively, are each coiled round externally with ten strong iron wires, consuming nearly 20,000 miles of such wire in each cable, without reckoning extra for twist. According to careful experiments, it has been found that a i^-inch iron- wire rope, weighing 20 ozs. per fathom, is as strong as a 3-inch hempen rope weighing 36 ozs. per WOA 437 WOO fathom, and so on up to great thick- nesses ; whence we are told that a 4^-inch wire rope. I5|lbs. to the fathom, will bear as great a strain as a 12-inch hempen rope of 363- Ibs. to the fathom. Wire -ropes are made, though much less exten- sively, of steel, copper, brass, and other metals. In reference to the use of wire for suspension bridges, Messrs. Howell of Sheffield, in 1868, proposed to use bands or ribbons of rolled steel, laid one on another, breaking joint so as to extend to any length ; they are to be suspended from tower to tower, and coated or covered to exclude the wet. It is thought that such a bundle of steel bars would be more rigid and dura- ble than twisted wire ; more strong and easy to" erect than parallel wires. "Woad, one of the dye-drugs, is obtained from a plant cultivated in many parts of Europe. The plant, at a proper age, is cut down with a scythe, washed, and the leaves stripped off; the leaves are dried, ground in a mill to a smooth paste, and the paste hardened into balls or lumps. When employed as a dye, woad produces a durable blue colour ; but its use has been some- what lessened by the extensive in- troduction of indigo. Wood. (See TIMBER, and other articles there referred to.) Wood Carving-. (See CARV- ING.) Wood Engraving:. In M-ood- cut pictures, the block (usually of box- wood) has the device or picture on the smooth surface, to receive ink in the same manner as type ; whereas all the parts which are not to be inked are cut away. This process is just the reverse of the one usually adopted with metal plates. (See COPPER-PLATE ENGRAVING.) Unquestionably this is the most use- ful of all kinds of engraving, be- cause printing from such a block can be effected in the same way as, and at the same time with, letter- press, and because stereotypes and electrotypes can be taken from the one as well as from the other. Wood-engraving has been the great source of success in the illustrated newspapers, and illustrated litera- ture generally. The Turkey box- wood to form the blocks is cut into slices, across the grain, equal in thickness to the length of a type (about an inch). The surface, ma\le perfectly smooth, is coated with a thin layer of white chalk. The picture is drawn upon this white surface, partly in pencil, partlyin Indian ink. The engraver uses very fine and sharp cutting tools to cut out the wood between the lines of the device ; and remarkable tact is shown in leaving all the lines them- selves intact. For very large wood- engravings, such as the two-page and four-page pictures in the Illus- trated London News, many blocks are required, nicely joined edge to edge : to save time, the separated portions are handed to different en- gravers, and screwed up together afterwards. For coarse purposes, maple, pear, or plane-tree wood is used instead of box. Wood Spirit; Wood Acid. Some of the products obtained by distillation from wood are noticed under METHYLATED SPIRIT, NAPHTHA, PYROLIGNEOUS ACID, and PYROXYLIC SPIRIT. Wood - 'working 1 Machines. Timber, like metals, has in late years undergone vast changes in regard to the mode of working it up into use- ful forms. The hand-worked saw, adze, plane, chisel, gouge, c., will necessarily remain in use for all smaller operations ; but we are every year advancing in the employment of cutting and shaping machines worked by steam power. There are factories now which will turn out doors, window frames, panels, mouldings, and the like, to any ex- tent, and ready for immediate use by the builders. The machines in woo 438 woo some instances resemble those noticed under MACHINE TOOLS ; but others bear more immediate re- lation to the softness of the material on which they are to work. One reason for the great success of the first Industrial Exhibition (1851) was the punctuality with which the opening was effected on the pre- arranged day; and this was only ren- dered possible by the use of steam- worked machinery in shaping the wood-work. The hand-rails for the galleries and staircases, the Paxton gutters or rafters, the box gutters, the sash-bars (200 miles of them) all were shaped by machinery. Some of the more useful machines for working in wood are the following : (I.) Vertical-saw Frame. This is an assemblage of saws, placed pa- rallel at short distances apart, and in a vertical position. Steam power (or it may be water power) works the frame up and down, and all the saws with it. If a log of timber were to be cut into inch planks, the saws would be fixed an inch apart, and so on. The timber is driven up to the saws, by being fixed on an iron carriage to which motion is given. Some of the machines are large enough to take a log 50 feet long by 42 inches in diameter. (2.) Veneer-sawing Frame. This re- quires the saws to be very thin, to be made of superior steel, to be placed at very small distances apart, and to be adjusted with rigorous ac- curacy, otherwise it would be im- possible to cut thin veneers without wasting much of the wood, which is often choice and valuable. The sawing action is rotary, not up and down. Each saw consists of several segments of a circle, fastened to a cast-iron disc. (See SAW MILL; VENEER.) (3.) Circular-saw Bench. This consists of two or more cir- cular saws, fixed vertically in a bench, the bed or top of which receives the piece of timber ; the timber is driven towards the saws, which speedily rip it up into pa- rallel strips of pre-arranged width. (4.) Cross-cut Saw Bench. The saws and the bench are here so adjusted that cuts are made cross- way of the grain, determining the lengths of pieces of wood with as much nicety as the other saws have determined the width. (5.) Roller Planing Machine. This very effec- tive contrivance has a row of rollers by which the wood is guided ; while fixed and stationary cutters exert such varied kinds of action as to plane, joint, rebate, tongue, and groove, or any one or more among these processes. (6.) Moulding Machine gives all the various forms of ogee, fillet, hollow, and round to the wood, with which we are familiar in wood- mouldings for joinery and picture- frame making. The cutting tools are fixed to revolving blocks, and will cut the wood on one or on both surfaces at once ; or they will pro- duce plane smooth surfaces and edges, with or without any mould- ings. (7.) Circular Moulding Ma- chine. A familiar work is here per- formed upon pieces of wood having a curved shape not suitable for treat- ment by the last-named machine such as circular heads for sashes, hand-rails, and table-edges. (8.) Tenoning Machine. A tenon being a peculiar projection in the end of one piece of wood to fit into a particular cavity in another, this machine is so adjusted as to give precisely the proper shape and size to the tenon. (9.) Vertical Boring Machine is, as its name denotes, a contrivance for boring or drilling circular holes, as it will make any hole from a fraction of an inch to 3 inches diameter, and from an inch to 1 6 inches in depth. (10.) Hori- zontal Boring Machine acts nearly in the same manner, but in a differ- ent direction. Sometimes a special tool follows the borer, to give a square form to the round hole. Mr. Cola, having in view the kind of woo 439 WOO wood - working machinery which would be valuable in India, gives some useful information as to the cost of such machines of moderate size. A timber frame of 36 inches, with all the saws, clips, rack car- riage, pinions, &c., suitable for saw- ing up logs into boards or scantlings, ^"350 ; a planing machine, with adjustments for jointing, grooving, and tonguing, and sets of cutting tools, ^300 ; a moulding machine, with all its accessories, ^"120; a veneer-sawing machine, with 10 feet disc, with segment saws, ^,^230; a circular-saw bench, with saws of 42 and 36 inches, $&', double tenoning machine, 220 ; squaring, cross-cutting, circular moulding, and vertical boring machines, ^310. The steam power and the accessories for working all these machines would vary according as the door and win- dow work is or is not combined with the rougher operations. He gives on a plan the dimensions and arrange- ments of a mill in which both of these departments are combined with a packing-case making and wheel-making shop. "Wool, as distinguished from hair, is remarkable for a series of minute saw-like teeth covering the outer surface, perceptible under the micro- scope. These teeth enable one fibre to cling to another in that inter- lacing way which permits of felting, and therefore of the manufacture of felted or napped cloth. Some of the Asiatic varieties of the goat have a fine coating of this wool under the long hair ; but the sheep is the animal which exhibits it in greatest abundance. The serrations are so minute that 3,000 of them exist in an inch of fibre ; and yet they are strong enough to produce the felting quality. The ancients knew nothing of the existence of these serrations ; but they appreciated the value of sheep's wool as a textile material, and made cloth from it in very re- mote times. It gradually became known that short fine wool is best fitted for being carded and made into woollens ; whereas long coarse wool is more suited to be combed and made into -worsteds a, distinction which is now of great importance, seeing that it leads not only to the production of different kinds of goods, but to the rearing of different breeds of sheep, according to the kind of wool required. Moreover, the woollen trade and the butcher's trade have certain mutual relations, seeing that fine mutton and fine wool are not necessarily obtained from the same breed of sheep. The most beautiful wool for felting into super- fine cloth is obtained from the merino sheep of Spain; but by skilful crossing of breeds, wool nearly if not quite equal in quality is now obtained from the sheep of some other countries, especially Saxony. A merino fleece averages 8 Ibs. from the ram and 5 Ibs. from the ewe ; the fleeces from other lands vary much more widely in weight. So far as regards England, it is known that fine felting wool can be grown here ; but the grazier finds such a sure market for the best mutton at good prices, that he attends more to the flesh than to the wool ; the con- sequence is, that we import nearly all our wool for making fine cloth. The wool from English sheep is mostly used in making coarse cloth, flannel, blankets, and worsted goods. The wool obtained by annual shear- ing is fleece wool, but that from the slaughtered animal dead wool. When sheep have been sheared, the yelk would ferment and rot if not previously in part or wholly removed. This yelk is a peculiar oily secretion, which mats or glues the fibres to- gether. It is customary to wash the sheep, therefore, before shearing : the yelk helps to make a kind oi soap for this purpose. Wools in the grease or in the yelk have not been washed, and fetch lower prices in the market; hand-washed wools woo 440 woo have been washed in a running stream ; scoured wools have been scoured and cleaned after shearing, and are the cleanest of all. Of the three kinds most largely imported for English use, German wools are the finest and most costly ; Australian the next ; and Cape of Good Hope the least : wools from other countries are less in quantity and more varied in quality. The length, the fineness, and the softness of the fibres all influence the price, because they affect the kind of cloth which the wool is fitted to make ; and the cleanness is, of course, an element in price. It is supposed that English sheep yield about 150,000,000 Ibs. of wool annually; but this is far below one-half of the quantity re- quired for our mills, insomuch that 230,000,000 Ibs. of foreign wool were imported in 1867. Notwith- standing this, we exported 9,000,000 Ibs. in that year : possibly English wool suitable for some particular kinds of foreign goods. Woollen-cloth Manufacture. The best woollen cloth is made wholly of new wool ; the exceptions to this rule, for inferior cloth, will be noticed presently. The processes are more numerous than in the cot- ton manufacture, owing to the pecu- liarities connected with the nap of the cloth, (i.) Sorting. Every bag or bale of wool, weighing from i to i \ cwt., contains various quali- ties of fibre, which require to be separated for different kinds of cloth. A sorter, with the wool opened and spread out before him on a table, separates it into kinds. The names given to these kinds are curiously technical : picklocks, prince, choice, super, head, downright, seconds, fine abb, coarse abb, livery, short coarse, breech, &c. The sorter makes as many subdivisions as the kind of wool suggests. (2.) Scouring. The sorted wool is scoured or washed in alkaline liquor heated to a tempera- ture of 120 Fahr., to drive out as much of the grease and dirt as pos- sible, after which it is washed in clean water. (3.) Dyeing. If the cloth is to be dyed after weaving, it is called piece dyed ; if before, wool dyed. The processes of the dye- house are such as are noticed under DYEING. The prevalence of black cloth for civilians, and of scarlet for the military, has led to particular attention being paid to these two colours. (4). Deviling. The willy or devil is a wooden cylinder studded with iron spikes, and enclosed in an outer case. The wool, fed into the machine along an endless web, is pulled asunder by the revolving spikes. This renders the fibres easy to work, and at the same time shakes out dust and dirt from between them. (5.) Picking. The opened wool, spread out on a table, is examined by women, who pick out and sepa- rate all slight impurities, which would otherwise deteriorate the cloth. In some factories a burring machine is used for this purpose, comprising a number of fluted rollers, iron beaters, and comb cylinders, which cleanse the fibres in various ways. (6.) Oiling. The wool, by this time nearly free from impurities, is spread out in a thick layer on a stone floor, and sprinkled with Gallipoli or some other oil : I Ib. of oil to about 6 Ibs. of wool. It is passed a second time through the willy, to mix the oil with the fibres. (7.) Scribbling. The scribbling machine converts the mass of oiled wool into a broad, thin, flat fleece or lap, with the fibres opened and separated. It is used two or three times over, to effect this separation more completely. (8.) Carding. The carding engine, like the scribbling machine, is simi- lar to the machines used in the cotton manufacture, seeing that its action depends chiefly on comb- teeth fixed to revolving cylinders. The engine, after combing the woo), brings it to the form of separate flat slivers, a few feet long, and then woo 441 woo into round ravings, like short pieces of soft cord. (9.) Stubbing. The dubbing-billy is a machine com- prising a movable frame, spindles, rollers, and wheels, so adjusted that, when the rovings are placed upon a kind of endless apron, they are drawn into the machine, joined end to end, stretched, and slightly twisted. An improvement on the slubbing-billy is the slubbing ma- chine. A more recent invention, called the condenser, combines the slubbing with the carding processes. (10.) Spinning. Wool is more fre- quently spun by the mule process than the throstle process. These are described under SPINNING. (n.) Spooling. Matters are by this time advancing towards the weaving of the wool into cloth. The yarns are wound upon bobbins, trans- formed into skeins by a kind of reel, and then spooled, or wound upon another set of bobbins called spools. (12.) Weaving. After sizing, beam- ing, and one or two subsidiary pro- cesses, the yarns are -woven into cloth. (See WEAVING.) In the technical language of the woollen- mills, a bier is 40 warp threads ; 5 biers make a hundred; in ordi- nary broadcloth of i^ yards wide there are 1 8 of these double hun- dreds, or 3,600 separate warp threads ; finer cloths will go up to 6,000 threads or more. The pro- cesses of weaving are very much varied, according as the cloth is to be single, double, twilled, napped, ribbed, &c. (13.) Fulling; Teaz- ling; Shearing. Then comes the operation by which the cloth is thickened, narrowed, and shortened, and the fibres matted or felted to- ether; for which see FULLING, 'ULLING MILLS. Next the remark- able mode of working up the surface into a pile or shag ; for which see TEAZLE, TEAZLING. And after that, the delicate operation of cut- ting the pile into a smooth nap, described under SHEARING. (14.) Finishing. The cloth is now nearly finished, and only requires a few final processes. It is piled up into a heap, with smooth metal plates between them ; heavy pressure gives a smoothness and a glossiness, which are increased if the plates are first heated. This is aided by boiling or steaming, and by brushing, which remove certain defects produced by the pressing. Sometimes rolling is introduced, over cylinders which permit steam from within to act upon the cloth. For a few statis- tics of this important trade, see WORSTED MANUFACTURES ; the relation between the short- wool and the long-wool branches of industry will thus be better seen. It is worthy of note that the first piece of woollen cloth ever produced in Australia was early in 1868, after many difficulties arising from the importation of suitable machinery and the unskilfulness of the men. It was made at a new factory esta- blished at Geelong, in Victoria. Woolwich. Gun. The large guns now manufactured by the Govern- ment at Woolwich are called in- differently Woolwich and Frazer guns ; the former name referring to the place of manufacture, the latter to the inventor. They are not actually original in any of their features, but are a combination of many excel- lences in construction and modes of firing. The beautifully-fitted work- shops which used some years ago to produce the Armstrong guns are now supplied with all the require- ments for this new arm. The Frazer gun is a rifled muzzle-loader, made of a combination of iron and steel. Before the Crimean war, the cast- iron guns for the British service were supplied by contract from theCarron, the Low Moor, and other iron- works ; while the brass guns were made by the Government at Wool- wich. But now, in the days of ordnance of vast size, it is found that cast-iron is not a suitable woo 442 WOR material ; and wrought-iron or steel is therefore substituted for it, or in some cases combined with it. A coiled bar of the best wrought-iron now most usually forms the chief part of the gun. The bars for a large gun may be 25 feet long by 7 inches wide ; several are welded end to end to form a very long bar ; and this bar, at a white heat, is forcibly coiled round a mandril, to the full length of the gun. A second, third, and even fourth coil are simi- larly twisted on, according to the required thickness of the gun. The successive threads are nearly close together; but to produce complete homogeneity, the coil is subjected to a tremendous forging by a steam hammer capable of bringing down a momentum of 2,000 tons at once. When cold, the gun is turned to the exact size internally and externally, and exquisitely smooth. The trun- nions and the breech-piece are struck on hot over the main tube. There is a gradual tendency to use steel instead of wrought-iron for the inner tubes ; but the principle of building up is mainly the same. The rifling of the Frazer gun is on what is called the Woolwich system the result of many trials, and a com- bination of excellences derived from various quarters; for it was notknown, until after extended experience, what was the best number, form, or twist of the rifle grooves. Naval officers have finally decided against the Armstrong breech-loaders for use in boats and on shore, and Frazer's muzzle-loaders are being substituted for them. Military officers also re- commend the latter as field-^uns, to consist of wrought-iron breech and trunnion pieces over a steel tube, the tube being rifled with three grooves ; they are found to be as effective as Armstrong guns, while they are cheaper to make and handier to work. The rapid discomfiture of King Theodore at Magdala in 1868 was in great part due to the admirable work- ing of a few small steel Woolwich guns, made expressly for mountain warfare ; each weighed only 145 Ibs., and hurled a small 7-pound shrapnell shell with wonderful precision, range, and force. The largest kind of Woolwich gun made at the present time (end of 1868) is a 13-inch 600- pounder, a rifled muzzle - loader weighing 23 tons ; it is 14 feet 2 inches long, with 4 feet 6 inches external diameter at the breech ; it is rifled with nine grooves. Though called a 6oo-pounder, a spherical steel or chilled-iron shot adapted to it weighs 620 Ibs., and will bear a charge of 75 Ibs. of powder. The next size is the 9-inch 26o-pounder ; and the next the 7-inch 1 15-pounder. Wootz is a peculiar kind of steel made in India, supposed to owe its properties to a small admixture of alumina with the iron and carbon. When the polished surface of steel so made is washed over with sul- phuric acid, there is produced that peculiar wavy appearance which be- longed to the original Damascus sword-blades. (SeeDAMASCENiNG.) Workshops, Floating. During the war with Russia in 1854-5, a plan was adopted which strikingly illustrated the kind of aid rendered to warlike operations by science and mechanism. When Sir Charles Napier's fleet went to the Baltic in 1854, he took with him a steam frigate called the Vulcan, fitted out by Mr. Nasmyth as a floating work- shop, for the repair of the ships belonging to the fleet. Instead of taking a damaged ship to the work- shop, the workshop was taken to the ship. The first deck was con- verted into an engineering shop, 104 feet long, 30 feet wide, and 10 feet high; provided with a 12- horse-power steam-engine, turning lathes, planing machines, boiler-plate punching and shearing machines, drilling and boring machines, forges, blowing fans, a cupola furnace, a steam hammer, and all the tools and WOR 443 WOR implements necessary for ordinary engineering work. The English ships suffered very little during that war, and the floating workshop was not brought largely into use ; but the efficiency of the whole scheme was undoubted. Such an engineer- ing shop, that can travel about from sea to sea and from port to port, is likely to be valuable for the arts of peace as well as those of war. Worsted Manufactures. As long wool possesses the felting or fulling property much less fully than short, the two kinds are adapted for different kinds of goods. Stuffs and worsteds are the generic names for the long-wool goods ; but there are many other designations. The processes of manufacture are less numerous than for woollen cloth. ( I . ) Washing . When the bags of long wool are opened, the wool is washed in soap and water, to drive out as much of the grease and dirt as may be practicable. It is removed to a drying-room, where, spread over the floor, it is dried at a moderate heat. (2.) Plucking. The dried wool is con- veyed to a machine, where, instead of being torn asunder by spikes on a revolving cylinder, the locks or tufts are opened by the action of fluted rollers. (3.) Combing. Long wool must be combed more thoroughly than short, as its excellence depends on other qualities than those of felt- ing. In hand combing the work- man employs two combs and a post. The comb consists of long steel spikes fixed into a back, which is held by a handle. One of the combs, heated over a peculiar kind of stove called a comb-pot, is fixed temporarily in the post, with the spikes upper- most ; and then the comber, taking a handful of wool, sprinkles the fibres with oil, and draws them re- peatedly over and between the spikes, which comb them out. He places the comb and wool over the stove to renew the heat, and mean- while operates in a similar way with the other comb; then the two combs, with their two charges of wool, are drawn over each other, the spikes of one uppermost and those of the other downwards, whereby the combing is carried still further. Another combing follows at a lower heat. The short fibres combed out by this process, called noyls, are reserved for spinning into inferior goods. In ma- chine combing, as an improvement on a laborious and unhealthy em- ployment, the wool is temporarily fixe'd to the surfaces of two cylinders studded with teeth ; the cylinders revolve near each other, and the teeth on one comb comb the fibres attached to the other, the cylinders being heated to the proper tempera- ture by steam power within. (4.) Breaking. The wool, separated into slivers by combing, is laid upon a feeding-apron ; as this apron travels forward, other slivers are laid on, so overlapping as to get entangled with the ends of those first applied ; this is continued until many slivers be- come united into one continuous length, the breaking frame being so constructed as to facilitate this ope- ration. (5.) Drawing. The long slivers, received into cases, are trans- ferred to the drawing frame, which acts very much in the same way as the breaking frame, uniting into greater lengths the pieces which have been. in shorter lengths, but at the same time twisting them slightly, and winding them on bobbins. The speed with which the drawing frame works regulates the length and tensity to which the fine soft cord is brought. The roving, spinning, and weaving processes bear a good deal of resemblance to those de- scribed in connection with the cot- ton manufacture much more so than with the woollen-cloth manu- facture. Of the chief varieties of woven goods made from wool, or wool intermixed with silk or cotton such as baize, blanket, bombazine, WOR 444 YEW bombazet, calimanco, camlet, carpet, challis, Cashmere, cr&pe de Lyons, doeskin, drugget, flannel, flushing, hosiery, kerseymere, Meltons, merino, moreen, mousseline-de-laine, Nor- wich crape, Orleans, Petershams, pilots, Saxonies, say, serge, shal- loon, stuff, "waistcoating, &c. the more important are noticed under those headings. For goods in which old wool is mixed with new, see SHODDY. In reference to the ex- tent of the woollen and worsted manufactures, taken in all their com- pleteness, the following figures may be useful: In 1867, England im- ported 230,000,000 Ibs. of wool, 6,000,000 Ibs. of yarn, and a com- paratively small quantity of woven goods in wool. The exports com- prised 9,000,000 Ibs. of wool, 37,000,000 Ibs. of yarn, 31,000,000 yards of woollen cloth, and 200,000,000 yards of worsted and stuff goods. There was a rough estimate that in 1865 about 380,000,000 Ibs. of wool had been worked up into goods, valued at ^67,000,000. Wort is the sweet liquor produced \ by the mashing, or steeping of malt I and grain in hot water. (See BREW- ! ING; DISTILLING; VINEGAR MANUFACTURE.) Writing- Fluid. (See INK. Writing- Paper. (See PAPER.) Y. Yarn. Yarn or thread, in the state spun for weaving, is noticed under COTTON, FLAX, HEMP, JUTE, SILK, and WOOL. Yeast, or barm, is a ferment a substance which will produce fer- mentation under certain conditions. If dough be left for a time un- baked, it will ferment, and a por- tion of this fermenting dough will cause a whole batch of dough to ferment ; it is the leaven that leavens the bread. When beer or ale is fer- menting, it gives off an abundance of a peculiar froth. This froth is yeast, which will act as a ferment or leaven for other beer, or for bread. It is the sugar in the starch of the wheat or barley that seems to be the primary agent in this fermenta- tion. A kind called patent yeast is made from hops, malt, flour, and water, treated in a particular way, and itself set into an incipient fer- menting state by a little yeast added to it ; it is a kind of half-made beer or ale. No less than 116,000 Ibs. J of this dried yeast were imported in 1867. (See BREAD MAKING; BREWING; DISTILLING; VINEGAR MANUFACTURE.) Yeast may be dried into a hard, horny, semi- transparent mass ; but its fermenting property may be restored to it by steeping for some time in water. Yellow Dyes and Pigments. These comprise arnatto, fustic, French berries, Persian berries, saw- wort, quercitron, turmeric, -weld, and many other products of the vegetable kingdom, as well as some of the acids and metaDic salts. The more important of these are noticed under their proper headings. Yellow Ochre. (See OCHRE.) Yew. The wood of the common yew is very useful for a multitude of purposes, on account of its hardness, and the large pieces which can be obtained from the trunk. Many other kinds of yew also yield valu- able wood ; while there are other parts of the tree occasionally useful in medicinal preparations. ZAF 445 ZIN z. Zaffire is one of the names for cobalt or smalt. Zinc. This metal is much more largely used than was the case a few years ago, chiefly owing to improved modes of working it. In China and India it was employed for orna- ments at a very remote period ; but its use (except combined with cop- per) in Europe is comparatively modern. The metal, when pure, is bluish white, brittle at ordinary tem- peratures, becomes malleable and ductile between 2 1 2 and 300 Fahr., ;ind then retains its malleability when cooled down. It is veiy useful for baths, spouts, water tanks, pipes, engravers' plates, roof covering, voltaic batteries, a coating for iron plates, ship sheathing, tiles, and many other purposes. Perhaps its greatest value consists in its com- bining with copper to make Brass (which see). The demand in Eng- land for zinc is larger than the home supply. Zinc Smelting-. Zinc is smelted very extensively in Silesia and in Belgium, but not much in other parts of Europe. The metal is obtained from many different kinds of ore. In the zinc-smelting works of Bel- gium (the chief of which is at Vielle Montagne, near Liege), the ore used is chiefly a mixture of silicate and carbonate of zinc. 'After "washing, the furnace processes begin. The ore is first roasted in a furnace some- thing like a lime-kiln, where it loses about 25 per cent, of its weight, chiefly water and carbonic acid. After being ground to powder under edge-runners, it is smelted. The furnace for this process is very pecu- liar. Forty or fifty retorts of refrac- tory clay are inserted into an opening over the fire-place ; each retort is 44 inches long by 6 inches bore ; within it is a cast-iron conical adapter 16 inches long ; and within the adapter a wrought-iron cone I inch diameter at the thick end. The charge con- sists of i,ioolbs. of prepared ore and 550 Ibs. of fine bituminous coal, well mixed ; it is shovelled into the retorts, where it is exposed to heat, the adapter and the cone being used to facilitate some of the processes. The metal becomes separated from the other components of the ore by a kind of distillation, and is drawn from the retorts into moulds, which form it into flat square ingots of about 80 Ibs. weight. In the smelt- ing-works of Silesia there are seve- ral muffles arranged in two rows on either side of a central fire-place ; each muffle is about 42 inches long by 20 inches diameter, and is con- nected at one end with a pipe, which with it makes a somewhat large re- tort. The charge consists of equal parts of roasted ore and fine cinders. The process is one of distillation, as in the Belgian plan, and the zinc is cast into blocks or ingots. In the smelting-works of England and some of the countries of the Conti- nent, various ores are used such as the red oxide ; the sulphide, blende, or black jack ; the carbonate, or calamine ; and the silicate, or elec- tric calamine. The zinc ores of Somersetshire are mostly smelted at Bristol, those of North Wales at Birmingham, and those of Northum- berland and Cumberland at Shef- field. Calamine is the most abun- dant and the most easily worked. After being roasted or calcined, and ground under heavy edge-runners, it is ready for smelting. The fur- nace is something like that used in glass-houses. Six earthen pots or crucibles are ranged in a circle ; each has an iron tube proceeding from the bottom, and descending to a vessel below ; and each is covered with a tile temporarily cemented to it. A low dome, pierced with six circular openings, arches over the six crucibles. The roasted and ZIN 446 ZOE crushed ore, mixed with powdered coal in certain proportions, is put into the crucibles, the fires are kin- dled, and various openings closed. The zinc is distilled from the ore, and descends through the tubes to the vessels below, where it con- denses into drops. This zinc is then cast into ingots for sale or use. Zinc White. The deleterious qualities of white-lead being well known to house - painters (see WHITE-LEAD) , oxide of zinc is some- times used instead. It is prepared from metallic zinc in a particular stage of its evolution during the smelting process. The zinc white thus made is a white, tasteless pow- der, which is mixed with oil to make paint. Medical men strongly ad- vocate the substitution of zinc white for white-lead; but painters say that it has a tendency to crumble and peel off, as it does not combine intimately with the oil. Zinc "Working. The pigs of zinc, as prepared in the smelting furnace, are ready for conversion into a large number of useful forms. The ingots or blocks are melted in a reverberatory furnace, containing a well or hollow in which the melted metal accumulates. It is ladled out of this receptacle into moulds, which are of various sizes and forms, accord- ing to the after-processes. The plates or slabs thus made are heated at a second furnace to about 212, at which temperature they can be rolled into sheets by an ordinary rolling- mill. It is the facility of rolling when hot (a comparatively modern discovery) that has brought zinc so much more largely into use in recent times. Zinc is very flexible ; and thin sheets, stamped and perforated sheets, mouldings and headings, nails and spikes, wire of great flexibility all are produced in abundance : statues, busts, and statuettes are also cut in this metal, as well as ornaments of various kinds. Vessels for containing and conveying Water | are another mode of use ; and zinc | roofing is much used, as beinglighter than sheet-lead. Zincing, or the I coating of other metals with a thin ! layer of zinc, is a very useful form of 1 using. In zincing iron, the iron is i first cleansed in a weak warm solution of sulphuric and muriatic acids ; then scrubbed with emery and sand ; then immersed in a bath of muriate of zinc and sulphate of ammonia ; and then in a mixture of 6 parts of zinc and I of mercury, with a little sodium or potassium. Here it is highly heated ; and when the iron is taken out, at a temperature of 680 Fahr., it is found to be well coated with zinc : the amalgam of zinc and mercury would eat into and dissolve the iron if kept long at this temperature. Bars, plates, and slips of iron are in this way protected from rust and corro- sion, for ship use and other purposes ; and small chains, nails, wire, c., are similarly treated. Zoetrope, or Wheel of Life. This curious optical toy, in regard to its construction, is very simple. It usually consists of a sheet-metal or cardboard cylinder, about a foot in diameter by 8 inches deep, and a stand which will enable the cylinder to rotate on a vertical axis. There are thirteen equidistant vertical slits in the upper half of the cylinder. A strip of pictures, about 3 feet long by 3^ inches broad, is placed round the inside of the cylinder, below the slits. In some forms of the instru- ment the strip of pictures covers the inside of the slits themselves ; but in these cases there are slits in the pictures, &c. There are twelve pictures on the strip ; and when the wheel is made to rotate, and an eye looks through the slits, very curious optical effects are produced by the incongruity between the twelve pic- tures and the thirteen slits. Other ratios than that of twelve to thir- teen will produce analogous results.