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SUPPLEMENT 
 
 TO 
 
 DR. URE'S 
 
 DICTIONARY OF ARTS, MANUFACTURES, 
 AND MINES. 
 
London* : 
 Printed by A. Spoitiswoode, 
 New-Street-Squarc. 
 
RECENT IMPROVEMENTS 
 
 IN 
 
 ARTS, MANUFACTURES, 
 
 AND 
 
 MINES: 
 
 BEING THE 
 
 SECOND EDITION OF A SUPPLEMENT 
 
 TO THE 
 
 THIRD EDITION OF HIS DICTIONARY, 
 
 BY 
 
 ANDREW URE, M.D. 
 
 F.R.S, M.G.S. M. A.S. LOND. J IS. ACAD. N.S. PHILAD. ; S. PFT. SOC. NT. fiEUM. 
 HA NOV. ; MCLH. ETC. ETC. 
 
 LONDON: 
 
 PRINTED FOR 
 
 LONGMAN, BROWN, GREEN, AND LONGMANS, 
 
 PATERNOSTER -ROW. 
 
 1845. 
 
PREFACE 
 
 TO THE SECOND EDITION, 
 
 Having been unexpectedly called upon by my publishers, at the end of 
 about three months after the appearance of this Supplement, to revise 
 and improve it immediately for a fresh edition, as the whole impression 
 had been sold off, I have used all diligence in the brief period allowed 
 me, to make such emendations as seemed most beneficial and consonant 
 to the spirit of the work. The present additions are given in the second 
 Appendix. No exertions on my part can adequately recompense the 
 public for the favour bestowed on this humble compilation ; nor can 
 . words duly express the gratitude which I feel. By an auspicious coin- 
 cidence, if it be nothing more, the sentiments, and almost the language 
 used by me in the preface to this Supplement, written about the middle 
 of last October, in portraying the dwarfish and rickety condition of the 
 glass manufactures of this kingdom, under the swaddling-bands of the 
 excise, have been employed by o*ur prime minister, in his masterly 
 speech on the 14th February, on presenting his Budget to the House of 
 Commons. The views therein developed by Sir Robert Peel are worthy 
 of a great statesman, and give promise of the dawn of a wiser and more 
 liberal legislation for this manufacturing empire, which, rightly admi- 
 nistered, Would be the workshop of the world. 
 
 " Your export of earthenware was last year," said he, " double that of 
 glass ; it was to the value of 75 1,000/. ; but the export of glass, subject, as 
 I have said, to the duty, and the constant, vigilant, and annoying inter- 
 ference with the manufacturer, in order that it may be collected, was 
 only to the extent of 388,000/. I am about to state another important 
 fact in regard to glass ; there is no excise duty on glass, in France, 
 Belgium, or Bohemia ; and what was the consequence? That in Bohemia, 
 in particular, the manufacture by the application of the chemical arts, 
 has been brought to a state of admirable perfection. There, glass under 
 the application of the most beautiful chemical principles, is exposed at 
 different stages to various degrees of heat, and thereby contracts a 
 diversity of colours that produce the most beautiful effects. We have 
 peculiar facilities for accomplishing the same ends ; we command the 
 alkali and the coal, and yet we cannot compete with foreigners in the 
 manufacture of glass. There is a great import of foreign glass into the 
 bonded warehouses of this country, to be afterwards exported, and it 
 is now beating our own manufacture, not only in foreign markets, but 
 
vi 
 
 PREFACE. 
 
 even in the markets of our own colonies. If you permit this article to 
 be free of duty, it is difficult to foresee, in the first place, to what per- 
 fection this beautiful fabric may not be brought ; and, secondly, it is 
 impossible to say to what new purposes glass, manufactured by our skill 
 and capital, may not be applied. I have read in a French newspaper, 
 the Courtier de V Europe, within the last month, that in France they are 
 now manufacturing glass pipes for the conveyance of water, which cost 
 nearly 30 per cent, less than pipes manufactured of iron, and which will 
 bear a greater external pressure than iron pipes. They are luted together 
 by a species of bitumen, and as far as health is concerned for the con- 
 veyance of water, glass pipes are greatly entitled to the preference. It 
 is to be borne in mind, that the cost of collecting the duty on flint glass 
 is not less than 57 per cent. In order to prevent fraud, it is necessary 
 that you should have a series of most minute and troublesome regulations 
 as to the melting of glass ; notice must be given to the excise officers 
 respecting annealing and other parts of the process, which so encumber 
 it as to make the application of additional skill and ingenuity almost 
 impossible. My belief is, that with this change, if we do not supply 
 almost the whole world with glass, we shall at least be able to enter into 
 competition with other nations, who have hitherto had the benefit of 
 that supply."* 
 
 These forcible observations constitute a justifying commentary upon 
 the remarks on the excise nuisance of our manufactures, hazarded by me 
 four months before. The slight technical mistakes in Sir Robert's 
 statement, it would be ungenerous in a chemist to criticise, after the 
 above splendid eulogium pronounced on his magic art. 
 
 " Verum ubi plura nitent in carmine, non ego paucis 
 Offendar maculis." 
 
 The Bohemian glass owes its rich diversity of colours not so much to 
 alternations of temperature, as to the skilful use of a diversity of metallic 
 oxides. Water pipes are not, generally speaking, endangered by external, 
 but by internal pressure ; and if iron pipes be found in France not so 
 strong or so wholesome for the conveyance of water as glass pipes, the 
 fact proves French iron to be still weaker and more impure than even 
 we knew it to be. English cast-iron pipes are at least 152 times more 
 cohesive, or more capable of resisting pressure, than glass pipes, as has 
 been proved by the concurring experiments of Tredgold, Professor 
 Robison, and George Rennie, Esq., F.R.S.f 
 
 I hope and pray that Sir Robert Peel will go onwards in the career, 
 glorious for a statesman, of emancipating the industry of this kingdom 
 from the shackles fastened upon it for many years by class legislation ; 
 that purblind policy of the land Lords, pursued under the notion that in 
 evading the direct and simple operation of a property-tax, and throwing 
 the onus of taxation on the whole consumers of our manufactures at 
 
 * Hansard's Parliamentary Debates, 1845. No. HI n p. 490. 
 
 * Philosophical Magazine, Vol. l.,and Philosophical Transactions for 1«18. 
 
PREFACE. 
 
 vii 
 
 home and abroad, they were not counteracting the prosperity of the 
 state, and of consequence their own well-being, as the most considerable 
 members of it. 
 
 There is a second manufacture, of great interest to the health and 
 comfort of the people of this country, which stands much in need of the 
 minister's untrammelling hand ; namely, that of soap ; a manufacture for 
 which, in an export point of view, this country possesses peculiar 
 facilities, in the boundless productiveness of its alkali works. It is 
 remarkable, that the consumption of this necessary of civilised life has 
 not increased with the increasing wealth and commerce of the country ; 
 that the quantity used by the manufacturers of silk, linen, and wool has 
 not increased in proportion to the progress of these manufactures ; that 
 the export trade is in a ruinous state ; that the duty is from 40 to 50 per 
 cent, on the prime cost ; that one fourth (240,119/.) of the whole amount 
 collected is returned in drawbacks ; and, finally, that another large pro- 
 portion of that amount is wasted for the treasury in the costs of col- 
 lection, in maintaining the immense army of officers required to watch 
 and stand guard over each trader. 
 
 London, 13. Charlotte Street, Bedford Square, 
 26th March, 1845. 
 
PREFACE 
 
 TO THE FIRST EDITION. 
 
 In laying this Supplement to my Dictionary of Arts, Manufactures, and 
 Mines before the world, while I gratefully acknowledge the indulgence 
 with which that work has been received, may I be permitted to advert 
 very briefly to some of my present endeavours to render it less unde- 
 serving of public favour, though, after all my efforts, it will by no means 
 realise either my own wishes and intentions, or the expectations of all 
 my readers ? 
 
 To investigate thoroughly any single branch of art, we should examine 
 it in its origin, objects, connexion with kindred arts, its progressive 
 advancement, latest improved state, and theoretical perfection. The 
 general principles on which it is founded, whether belonging to the me- 
 chanical, the physical, the chemical sciences, or to natural history, should 
 be fully expounded, and tested by an application to its practical working 
 on the great scale. The maximum effect of the machinery which it 
 enrploys, and the maximum product of the chemical mixtures and opera- 
 tions which it involves, should in every case be calculated and compared 
 with the actual results. 
 
 Such have been my motives in the numerous consultations I have had 
 with manufacturers relatively to the establishment or amelioration of 
 their factories, and when they are kept steadily in view, they seldom fail 
 to disclose whatever is erroneous or defective, and thereby to lead to 
 improvement. It will not be denied by any one conversant with the 
 productive arts, that very few of them have been either cultivated or 
 described in this spirit. It is to be hoped, however, that the period is 
 not remote, under the intellectual excitement and emulation now so 
 prevalent in a peaceful world, when manufactories will be erected, and 
 conducted upon the most rational and economical principles, for the 
 common benefit of mankind. Meanwhile it is the duty of every professor 
 of practical science to contribute his mite towards this desirable consum- 
 mation. 
 
 It is under a sense of this responsibility that I have written the lead- 
 ing articles of this Supplement, having enjoyed some peculiar advantages 
 in my profession for making the requisite researches and comparisons. 
 I trust that not many of them deserve to be regarded as trite compila- 
 tions or as frivolous novelties, with the exception of a few of the notices 
 of recent patents, which I have intentionally exhibited as beacons to deter 
 from treacherous quicksands, not as lights to friendly havens* I have 
 sought sincerely to make them all conducive, more or less, to utility ; 
 
 a 
 
X 
 
 PREFACE. 
 
 being either new contributions to the old stock of knowledge, or additions 
 and corrections to the miscellaneous volume, of which the present is 
 the sequel. 
 
 Arrow Root is here for the first time treated as a well organised 
 manufacture, in conformity with my quondam definition ; " Manufac- 
 ture is a word which, in the vicissitude of language, has come to signify 
 the reverse of its intrinsic meaning, for it now denotes every extensive 
 product of art which is made by machinery, with little or no aid of the 
 human hand ; so that the most perfect manufacture is that which dis- 
 penses entirely with manual labour.* 
 
 Arrow root being the purest and most agreeable variety of fecula, and 
 therefore one of the most powerful nutriments, deserves more attention 
 from the colonial planter than it seems hitherto to have received. As 
 it has been now so judiciously prepared in the island of St. Vincent, by 
 the proprietor of the Hopewell estate, it will, I hope, amply repay his 
 enterprising and liberal spirit, seeing that he supplies us with an article 
 equal if not superior to the best from Bermudas, at two thirds of the 
 price. 
 
 To Artesian vVells an interesting notice has been added of the suc- 
 cessful labours of MM. Arago and Malot at Grenelle, near Paris. 
 
 I doubt not that should cockneys happen to read what is here said of 
 Bavarian Beer, they will feel no little surprise, mixed with scorn and 
 incredulity, when told that the mystery of brewing is more philosophi- 
 cally studied and incomparably better understood in Munich than in Lon- 
 don, and indeed throughout all Bavaria, than in Old England ; but such 
 is certainly the fact, as every delicate stomach will experience which is 
 cheered with the beverage of the former capital, and loaded with the heavy - 
 wet of the latter. The brief outline here offered to my readers has been 
 carefully drawn from the best sources of information, obtained during 
 several excursions into Germany. It will, I hope, induce the brewers of 
 this country to set more value on chemical science than they have here- 
 tofore done, and thereby eventually lead to a radical reform of our 
 colossal establishments for extracting from malt a beverage more akin to 
 that of fermented grape-juice, in its freedom from vinegar and gluten, so 
 abundant now in the greater part of the British porters and beers. 
 
 Under Biscuits will be found a complete description, with figures, of 
 the grand automatic bakeries of Deptford and Portsmouth, which provide 
 our hardy tars with the staff of life in the soundest state. 
 
 The perusal of the article Bread will prompt the wish that our land- 
 holding legislators would consent to let the people under their domina- 
 tion get, at a moderate cost, some of the wheat of southern Europe, 
 much richer than that of our average home growth in the azotised 
 glutinous principle, so essential to the formation of our blood and 
 muscles ; a wheat adapted to make a superior bread, such as that called 
 pain du gruau, in Paris, and also a superior macaroni, like the Neapo- 
 litan. In this department of industry, so important for the welfare of 
 
 * " Philosophy cf Manufactures," page 1. 
 
PREFACE. 
 
 xi 
 
 the population, the French have set us the example of applying to it the 
 economical resources of the factory system, having organised a self- 
 acting bakery, in which bread of the finest quality is made on the great 
 scale, in smokeless ovens of a nicely regulated temperature. Meanwhile, 
 the mass of her Majesty's subjects are dependent' for their bread upon a 
 multitude of tradesmen of slender means, who earn a scanty livelihood 
 by hard labour, and who work up a weak inferior flour into a bad 
 bread, which they are too often tempted to whiten with alum and other 
 unwholesome drugs. The penalty liable to be inflicted upon bakers for 
 having alum on their premises, is commonly evaded by letting it be added 
 to the flour in the mill. Why do not our wise legislators enact a law 
 for the summary conviction and punishment of a baker selling bread 
 with alum in it ; a saline compound most easily detected by chemical 
 analysis ? 
 
 I was lately called upon professionally to examine the very white 
 bread of a fashionable baker of high pretensions, and found it to contain 
 a notable quantity of alum ; so much so, as to have been directly offen- 
 sive to the stomachs, and hurtful to the health of several individuals in 
 the family using it. This is no solitary case, but is, I believe, that of a 
 large proportion of the bakers in London and suburbs, who operate upon 
 a partially damaged flour, as one may easily surmise from the disagree- 
 able odour exhaled from the hot loaves in too many of their shops. 
 Yet what individual will be Quixotic enough to attack the numerous 
 and ever changing arms of this Briareus ? Who would choose to 
 incur the trouble, responsibility, and expense of prosecuting a frequent 
 misdemeanour of this kind, relatively to which the want of fine wheat in 
 the market is a principal motive and apology ? 
 
 From these evils our grandees are exempt, as they bake their bread at 
 home of the best materials. Though they are apparently regardless of 
 the injury suffered by the public from this source, they are, however, 
 quite alert in the execution of the game and excise laws, the stringent 
 penalties of which are inexorably inflicted against petty transgressors, 
 exposed to temptations often too strong for the infirmity of human nature 
 to resist. 
 
 In every well governed state of continental Europe there exists a 
 Board of Health, or Conseil de Salubrite, composed of eminent physi- 
 cians, chemists, and engineers, appointed to watch over whatever may 
 affect injuriously the public health and comfort. In France, this com- 
 mission consists, for the capital, of seven members, who have the 
 surveillance, in this respect, of markets, factories, places of public 
 amusement, bakeries, shambles, secret medicines, &c. This tribunal has 
 discharged its functions to the entire satisfaction of their fellow citizens, 
 as appears from the following authentic report : — " Non settlement une 
 foule de causes dinsalubrite disparurent, mats beaucoup de moyens, de 
 procedes nouveaux furent proposes pour assainir les Arts et les Metiers, 
 qui jusque la avaient paru inseparables de ces causes oV insalubrite ; la 
 plupart de ces moyens eurent un plein succes. II riy a pas oVexemple 
 que les membres da Conseil appeles a donner leur avis sur des plaintes 
 
 a 2 
 
xii 
 
 PREFACE. 
 
 formees contre des fabriqucs, aient jamais repondu qu'il faHait les sup- 
 primer sans avoir cherche eux-memes a aplauir les difficultes, que 
 presentait aux fabric ants, Vassainissement de leur art, ct presque toujours 
 its sont parvenu a resoudre le probleme. Le Co?iseil de Salubrite, que 
 Von ne saurait trop sigfialer a la reconnaissance de publique, est une 
 institution que les nations etrangeres admirent, et s'efforceront d'imiter 
 sans doute."* 
 
 From this confident hope of emulation by other nations, the author 
 of these excellent observations would have excepted the United King- 
 dom, had he known how little paternal care is felt by the government 
 for the general interests of the people. In Germany, indeed, where the 
 fatherland feeling is strong in the breasts even of those rulers whom we 
 are apt to consider despots, similar boards of health are universally 
 established, whereas our legislative oligarchy frames laws chiefly for 
 the benefit of its own class and dependents ; as happened in the old time, 
 when there was no king in Israel to regard alike the interests of the poor 
 and the rich. 
 
 The Prussian municipal law (Allgemeine Landrecht) contains the 
 following enactments with regard to the sale of spoiled or adulterated 
 victuals. Th. II. Tit. 20. ; Abschnitt 11.; §§ 722 to 725. « No person 
 shall knowingly sell or communicate to other persons for their use, 
 articles of food or drink which possess properties prejudicial to health, 
 under a penalty of fine or bodily punishment. Whosoever adulterates 
 any such victuals in any manner prejudicial to health, or mixes them 
 with unwholesome materials, especially by adding any preparation of 
 lead to liquors, shall, according to the circumstances of the case, and the 
 degree of danger to health, be liable to imprisonment in a correction- 
 house, or in a fortress, during a period varying from one to three years. 
 Besides this punishment, those who are found guilty of knowingly 
 selling victuals which are damaged or spoiled (verdorbejier), or mixed 
 with deleterious additions, shall be rendered incapable for ever of carry- 
 ing on the same branch of business. The articles in question shall be 
 destroyed, if incorrigibly bad, but if otherwise, they are to be improved as 
 far as possible at the cost of the culprit, and then confiscated for the benefit 
 of the poor. Further, whosoever mixes victuals or other goods with 
 foreign materials, for the purpose of increasing their weight or bulk, or 
 their seeming good qualities, in a deceitful manner, shall be punished as 
 a swindler." 
 
 It is singular how, amid the law-making mania which has actuated our 
 senators for many sessions, that not even one bill has been framed for 
 the protection of the people from spoiled and adulterated foods and 
 drinks. 
 
 For the article on Brick -Making, my readers are indebted to a valu- 
 able communication to the Institution of Civil Engineers, and the judi- 
 cious remarks on it by several of its members. At its conclusion, a 
 notice is inserted of one of those abuses which too often recur in our 
 courts of judicature, in consequence of scientific witnesses merging the 
 
 * " Dictionnaire Technologique," torn. ii. p. 293. 
 
PREFACE. 
 
 xiii 
 
 dispassionate philosopher in the mercenary partisan, and striving to 
 mislead the judge and jury, by giving a one-sided view of the matter 
 submitted to their candid examination. Such procedure is injurious not 
 merely to the individual casuist, but to the cause of science. What a 
 close affinity is there between these quibblers and the venal philosophists 
 so graphically portrayed by Lucian ! 
 
 In addition to the sectional view of the four-coloured calico-printing 
 machine, given in the Dictionary, an outside view of this admirable 
 mechanism is now presented to my readers ; the two together constituting 
 the only good representation of it hitherto made public. 
 
 The production, properties, and manufacture of caoutchouc are treated 
 here in considerable detail, peculiar facilities having occurred to me for 
 the thorough investigation of this novel branch of industry. If, along 
 with the account now given, the articles Bookbinding, Braiding Ma- 
 chine, and Elastic Bands of the Dictionary be consulted, the student 
 will possess a pretty complete knowledge of caoutchouc. 
 
 Chocolate is also a new contribution to my work, which I have been 
 enabled to make in consequence of extensive experimental researches. 
 It is to be hoped that our intrepid sailors will be allowed to reap the 
 full benefit of the investigations which I made in their behalf, by desire 
 of the Lords Commissioners of the Admiralty, and that their daily 
 breakfast beverage will be for the future more soluble, emulsive, and 
 nutritious, than I found it to be on commencing my researches, at which 
 time about -three-fourths of the cocoa was so coarsely ground, for the 
 service of the navy, as to be left in a state altogether unfit for digestion. 
 
 The various new modes of producing pictorial impressions by the 
 agency of light on chemically prepared surfaces are described under the 
 titles, Calotype, Daguerreotype, Photography, &c. The somewhat 
 kindred copying art by electricity is treated under the article Electro- 
 metallurgy. 
 
 Fermentation will be found a useful companion to the account of 
 Bavarian beer ; both being calculated to invite brewers and distillers to 
 look more narrowly than they seem to have done into the interesting 
 world of organic chemistry, so successfully explored in Germany and 
 France, but so little studied in this country. 
 
 Gas Light has been contributed by a most intelligent friend, and 
 deserves to be regarded as a standard treatise on this important branch 
 of engineering, condensed into the shortest possible space consistent with 
 perspicuity. 
 
 Guano, destined ere long to become the chief pabulum of British 
 agriculture, and thereby to emancipate our landholders and farmers from 
 their cxositophobia, their dread of the importation of foreign corn, has 
 been discussed at considerable length from peculiar sources of information. 
 
 Under Iron and Smelting are given descriptions, with figures, of the 
 best plans of the apparatus for the hot-air blast, and for feeding the blast 
 furnace with mine, limestone, and fuel ; both being original contribu- 
 tions from an eminent engineer. 
 
xiv 
 
 PREFACE. 
 
 The Seed-Crushing oil manufacture is, I believe, now for the first 
 time in this country represented by a complete set of figures, exhibiting 
 the various parts of the wedge stamping-mill ; the oldest and probably 
 still the best plan of extracting oil from seeds. 
 
 Pepper presents an instructive example of the fallacy of chemical 
 evidence, sometimes too inconsiderately given in a court of justice. Were 
 the solemn sanctity of an oath rightly impressed on the minds of scien- 
 tific men, they would not testify to anything but what they did most 
 surely k?iow, and would escape the remorse and obloquy consequent, in 
 feeling minds, on having borne false witness against their neighbour. 
 
 The Saccharometer table printed at first for the Dictionary, but 
 omitted along with some other articles of less importance for want of 
 room, is now given with certain improvements. 
 
 Smoke-prevention is a matter of such moment to the comfort and 
 salubrity of all our large towns, and even of many semi-rural districts^ ( 
 that in promoting the publicity of Mr. Charles Wye Williams's unexcep- 
 tionably simple and successful plan for effecting a consummation so earnestly 
 to be wished for, I am conscious of merely discharging a professional duty. 
 
 Spinning exhibits a short but systematic view of the admirable self- 
 acting system invented by Mr. Bodmer, whereby all the operations in a 
 cotton factory are linked together in regular succession, and co-operate, 
 with little or no manual aid, towards turning out a perfect product. 
 This invention constitutes a true automatic era in textile factories. I 
 trust the author of these inventions will be duly recompensed for the 
 ingenuity and labours of very many years. 
 
 In the spinning of fine flax yarn by machinery, the greatest mechani- 
 cal conquest which our factories have made in our own days over the 
 industry of rival nations, a capital improvement has been recently made 
 by Mr. Westly of Leeds. His former invention, the screw gill or spiral 
 comb described in the Dictionary, under Flax, is now universally em- 
 ployed. His new contrivance is called the Sliver Roving, of which a 
 description will be found in the Appendix, having come too lately to 
 hand for insertion in its proper place. It promises to be a still more 
 valuable improvement in this difficult branch of manufacture than even 
 the spiral comb. 
 
 The table entitled Spirits exhibits the correspondence between the 
 technical nomenclature of our excise as reckoned in over-proof and under- 
 proof strengths, and the simple scale of specific gravity as understood 
 and agreed upon all over the world. Since alcohol alone, and not water, 
 is the subject of taxation, why not have an alcohol-meter, like that of 
 Gay Lussac, which shows at once the proportion of taxable stuff in any 
 spirit ? (See Alcohol in the Dictionary.) As, however, our excise laws, 
 like those of the Medes and Persians, are not likely to be changed in 
 conformity with any scientific remarks, the above table is a desideratum 
 to practical chemists. 
 
 Sugar of Potatoes, being a recent manufacture in this country, is 
 fully investigated from my own professional resources. 
 
PREFACE. 
 
 xv 
 
 Tobacco is discussed at considerable length, valuable materials for 
 this inquiry having been afforded in the Report of the recent Committee 
 of the House of Commons. While this plant is a rank weed, conducive 
 neither to the sustenance nor health of man, and therefore a most fit 
 object for deriving from its consumers a fiscal revenue, it affords 
 instructive lessons on the influence of our fiscal administration on arts 
 and manufactures. 
 
 When the duty on an article is more than ten times its intrinsic value, 
 it must become the subject of perpetual and enormous frauds, and engender 
 innumerable misdemeanours and crimes. Towards the prevention and 
 punishment of these transgressions of the fiscal laws, a cumbrous, 
 complex, costly, somewhat arbitrary and despotic system of espionage 
 and prosecution must be organised. The working of this vast machinery 
 is well shown in the Committee's Report, and must excite uncomfortable 
 feelings in every honourable mind. We here see, on a somewhat mag- 
 nified scale, the system of interference with, and prying into, processes of 
 art and manufacture which accompanies and characterises all the opera- 
 tions of the excise. This device for collecting revenue for the neces- 
 sities of the State, is the Pandora's box of the dethroned Stuarts, and 
 should have been expatriated with that ill-starred family. We may say 
 of it, Quicquid tangit, deornat. No branch of industry can acquire its 
 due development under its wiry training and fastening. Had the incubus 
 of the excise overlaid our textile manufactures of wool, cotton, flax and 
 silk, how dwarfish would their stature have remained, and how meanly 
 would they have quailed under the unrestrained labour of rival nations ; 
 whereas now they afford employment, with food, raiment, and lodging to 
 millions of our people. For the manufacture of glass in all its 
 useful and ornamental branches, this country possesses indigenous re- 
 sources superior to those of every other one, in its stores of fuel and 
 verifiable materials of every kind, and yet it is surpassed by France, 
 Switzerland and Bavaria, in glass for optical purposes, and by Bohemia in 
 the quality and execution of decorative glass. Our scientific chemists 
 have been obliged to get all their best glass apparatus from Germany, via 
 Hamburgh. 
 
 Surely our glass-makers are the same race of people as our manu- 
 facturers of iron, fine cotton yarn, muslin, bobbin-net, broad silks, &c, 
 which defy the competition of the world, and if unshackled by the excise 
 they would ere long turn the scale against their foreign rivals, now their 
 superiors. The incessant and vexatious espionage of the excise is a bar 
 to all invention in every art under its control. Who would expend 
 thought, science, labour, and money in maturing any discovery or 
 improvement, by experiments necessarily conducted under the eyes of 
 needy excisemen, who would tell all they have seen for a trifling bribe ? 
 Perhaps the gigantic scale of our spirit distilleries may be appealed to 
 in proof of the fostering care of the excise, under which they have been 
 reared. But this overgrowth, when well looked into, is no evidence of 
 a sound constitution, but merely of the depravity of a grovelling unedu- 
 cated people. In fact, our distilleries produced until very lately a very 
 
xvi 
 
 PREFACE. 
 
 impure and offensive spirit, strongly imbued with noxious fusel-oil, or 
 oil of grains (see Alcohol in this Supplement), and but for the recent 
 introduction of Mr. Coffey's still into some distilleries, they would all 
 have been yet sending forth a similar crude spirit. But though Mr. 
 Coffey was for many years an officer of excise, and therefore did adapt his 
 patent invention to all the just requirements of the revenue laws, he has 
 met with very vexatious obstructions in the erection of his stills and on 
 the most frivolous pretences. 
 
 As a general corollary from my long experience in the conduct of arts 
 and manufactures, I feel warranted to declare, that the excise system is 
 totally incompatible with their healthy growth, and is in itself the fruitful 
 parent of fraud, perjury, theft, and occasionally murder. The sooner this 
 portion of the revenue, so oppressively, so expensively, and so offensively 
 collected, is replaced by an equitable tax on property, the better for the 
 welfare of this great country. I have no quarrel with the gentlemen 
 who administer the excise laws ; several of them with whom I have been 
 professionally conversant I esteem very highly as intelligent and upright 
 men, who do what they deem their duty in a conscientious manner. 
 But in concluding a very extensive survey of the great branches of 
 our national industry, this vile obstacle to their progressive growth be- 
 came so manifest, that it would have been pusillanimous to shrink from 
 the task of pointing out the magnitude of the evil* 
 
 Ventilation describes the plan now organised in the Reform Club 
 House, which I inculcated in the Philosophy o£ Manufactures, published 
 in 1835, as also in a paper read before the Royal Society in 1836, and 
 which was copied into several of the scientific journals of that period. 
 About the same time, Dr. Reid was erecting a huge factory furnace and 
 chimney for the ventilation of the House of Commons, which would have 
 been accomplished more effectually at one half of the expense, and without 
 any architectural disfigurement, by my method of ventilating fans, which 
 was, in fact, that long practised in our great textile factories. The Doctor 
 has, I understand, renounced his chimney draughts in ventilating the Court 
 of Exchequer at Westminster, and adopted a similar system to that of 
 the Reform Club House. I hope he will pursue the same plan in the 
 new Houses of Parliament, as it may be mounted at a very small cost, 
 and without occasioning the least unsightly appearance or any annoy- 
 ance. 
 
 I have subjoined in an Appendix a brief treatise, entitled Chemistry 
 Simplified, which, being duly studied, will prove a useful guide to 
 practitioners in testing alkalis, acids, and bleaching substances, in several 
 departments of the chemical arts. 
 
 A few of the articles marked in the Dictionary for reference to the 
 Supplement, were, on reconsideration, not found susceptible of useful 
 annotation. Most of these references were, indeed, statistical details, 
 which are given from the latest and best sources in Mr. M'Culloch's 
 excellent Dictionary of Commerce. 
 
 London, 13. Charlotte Street, Bedford Square, 
 28 ih October, 1844. 
 
SUPPLEMENT, 
 
 &c. &c. 
 
 ACETIC ACID. Rapid acetijication, or the quick formation of vinegar, was 
 practised upon malt worts in this country long before the rapid conversion of alcohol 
 into vinegar was introduced into Germany. In the year 1824, Mr. Ham obtained 
 his patent for an improved method of making vinegar, like that described in the Dic- 
 tionary. His son, Mr. F. Ham, of Norwich, civil engineer, states that for some years, four 
 of the largest country manufactories in the kingdom bave been at work upon his father's 
 plan, and that they are now in successful competition with the great London establish- 
 ments. The apparatus consists of a huge vat, in the centre of which is a revolving 
 pump, having two or more shoots pierced with holes, whereby a constant shower of 
 the fermented wort, called wash, is kept falling from the top. The underpart of the 
 vat contains the wash ; the upper part, birch twigs properly prepared, which are so 
 placed as not to interfere with the revolving shoots. Between the surface of the wash 
 and the rafters which support the twigs, a space of a few inches is left vacant, into 
 which one or more holes in the side of the vat admit the air spontaneously or have it 
 forced in. The wash is maintained, by steam pipes immersed in it, at a temperature 
 of from 90° to 100° F., so that, in consequence of the extensive application of the 
 atmospheric oxygen during the trickling through the twigs, it may be made sour in the 
 course of 48 hours ; but, in general practice, it is completely acetified in from 15 to 
 20 days. By this apparatus, a wort brewed from raw grain, with only one seventh of 
 malt, will produce a vinegar equal to that from malt alone; and the acetifying process 
 may be arrested whenever it is completed, thus preventing the risk of the vinegar 
 running into the putrefactive stage, as happens occasionally in the slow plan of ferment- 
 ation. The admission of air is so moderated as not to dissipate the alcohol of the 
 wash by evaporation. A wort of 24 lbs. gravity per Richardson's instrument, equal 
 to 1 -066 sp. gravity, will in this way yield an acid of revenue proof. 
 
 This old-going process is essentially the same with that for which John W. Neale 
 and James Edouard Duyck obtained a patent in September, 1841, with this difference, 
 that they employ the expressed juice of beetroots instead of corn wort. 
 
 The total number of vinegar factories in the United Kingdom was a few years ago 
 only 48, of which 5 of the principal are in London, 4 being on the Surrey side of 
 the Thames. In these, malt-vinegar-making is associated with the manufacture of 
 British wines, called "sweets" by the excise. The fermented wort or wash is acetified 
 either by " stoving or fielding." By the first plan, casks containing the wash are arranged 
 in close rooms, heated by steam-pipes or stoves. By the second plan, the casks, each 
 holding somewhat more than 100 gallons, are laid on their sides, with the bung- 
 holes up, and distributed in long parallel rows, two or more deep, with narrow lanes 
 between. A flexible pipe or hose, in connection with the great wash tun in the brew- 
 house, is laid alongside of the casks, for the purpose of filling them, and keeping them 
 supplied in case of leakage or evaporation. The Avash requires usually several months 
 for its complete acetification, during which time the bung-holes are left open in fine 
 weather, but covered with a tile in the time of rain. When the acetous fermentation is 
 completed, the contents of the casks are transferred by a syphon into a shoot laid on 
 the ground, whence it is drawn by a pump into a store vat within doors. It is next 
 clarified in very large vats, called " rapes," because in them it is filtered slowly and 
 repeatedly through a compacted heap of the stalks and skins of raisins, called rape, 
 which is the refuse of the British wine manufacture. 
 
 In 1838, 2,628,978 gallons of vinegar paid duty in England; in 1839, 2,939,665; 
 
 B 
 
2 
 
 ACETIC ACID. 
 
 and in 1840, 3,021,130; upon which the gross amount of duty was, respectively, 
 21,908/. 3s. ; 24,488, 17s. 6d. ; and 2.5,978/. 12s. 9d. 
 
 In Scotland, in the same years, 15,626 gallons ; 14,532 ; and 12,967 ; on which the 
 duty charged was, respectively, 130/. 4s. 4d. ; 1217. 2s. ; and 1 11/. 19s. Id. 
 
 In Ireland, in the same years, 48,158 gallons; 50,508; and 56,812; on which the 
 duty charged was, 401/. 6s. 4d ; 420/. 18s. ; and 489/. 13s. 
 
 In the German process of Schiitzenbach for the rapid formation of vinegar, 180 
 measures (of 2 litres, or 2 quarts each) of water are added to 20 of alcohol of from 
 44 to 45 per cent, by Tralles, and 6^ of vinegar, containing 3± per cent, of acetic 
 acid. These 206| measures produce on the average 203 to 204 of vinegar of the 
 above strength. The process of acetification in the graduation tubs (gradirfusser) 
 is finished in about 48 hours, and furnishes a vinegar of only 2 '75 per cent, of acid 
 strength. The liquid still contains some unchanged alcohol, and it is therefore 
 transferred into tuns, where it completes its oxygenation. The heat of the chamber 
 being about 90° F., occasions the stream of air that is passed through the above mate- 
 rials to carry off unproductively one tenth of the alcohol at least. Of the air that 
 passes through the apparatus, only 3 per cent, of its oxygen is converted into carbonic 
 acid.* An increase in the proportion of alcohol in the mixture is not found favourable 
 to increased prodviction of vinegar. 
 
 The theory of the acetification of alcohol was first fully cleared up by the researches 
 of Liebig on aldehyde. For the production of 100 pounds of hydrated acetic acid, 53 
 pounds of oxygen are required, which are contained in 227 pounds of air, and oxygenate 
 77 pounds of absolute alcohol. 
 
 The conversion of the alcohol of fermented liquors into vinegar may be chemically 
 represented as follows : — Alcohol is a compound of 4 atoms of carbon, 6 of hydrogen, 
 and 2 of oxygen, or in symbols C 4 H 6 O-. In certain circumstances (as the first stage 
 of acetification) it loses 2 atoms of hydrogen, and becomes aldehyde, or dehydrogenated 
 alcohol, C 4 H 4 O 2 . This body readily absorbs 2 atoms of oxygen on exposure to air, 
 and thus forms 1 atom acetic acid; in symbols, C 4 H 3 O 3 + 1 atom water (HO). 
 These results are obtained in the exposure of vapour of alcohol to platinum sponge, 
 or platinum mohr. In all cases it is presumed that aldehyde is first produced, then 
 vinegar. The quick vinegar process has been in this country advantageously applied 
 to the acetification of a solution of starch sugar made by the agency of either malt or 
 sulphuric acid. But as our excise laws are adverse to the spirituous fermentation of 
 such sugar, the starch liquor, after being boiled with 1 per cent, of sulphuric acid, is 
 directly fermented into a crude wash, which is then acetified by the following 
 method : — 
 
 A very large slightly conical tub or tun, 14 feet wide at bottom, 15 at top, and 13 
 high, turns out in a given time as much vinegar as is in Germany obtained from 6 tubs 
 8 feet high and 4 feet wide. Our larger mass of materials generates and maintains so 
 much heat in the oxidation of the spirit, as to require no stove-heating in a properly 
 constructed chamber. Two and half feet above the bottom of the above tun, a false 
 bottom is laid. The space above this bottom is filled with coopers' wood shavings 
 and chips, and the space beneath is destined to receive the liquor as it trickles down 
 on the true bottom, in order to be pumped up in continual circulation. At a moderate 
 height above the tun, the reservoir of the wash is placed, which discharges itself 
 through a regulating stop-cock, or valve, into a pipe in its bottom, which passes down 
 through a pretty large hole in the middle of the lid of the tun, and terminates a few 
 inches under it, in a cross pipe shut at the ends, which is made to revolve slowly by 
 mechanical power, in a horizontal direction round the end of the vertical pipe. This 
 cross pipe is long enough to reach nearly to the sides of the tun, and, being pierced with 
 small holes in its under side, delivers the fermented liquor, in minute streams, equally 
 all over the surface of the chips of wood. It thence falls into the lower compartment 
 of the tun, through holes round the circumference of the false bottom, whence it is 
 pumped up again, under certain modifications, to be presently described. 
 
 The air for oxygenating the alcohol into vinegar is supplied from two floating 
 gasometers, which are made to rise and fall alternately by steam power. The ascending 
 one draws its air from a pipe which passes into the centre of the tun, immediately 
 under the false bottom, and as it re-descends it discharges that air through a pipe into 
 a cistern of water, Which condenses, and retains the alcoholic vapour drawn off with 
 the air. This water is used in making the next acetifying mixture. The fresh air is 
 admitted in the top of the tun by the sides of the vertical liquor pipe, which is somewhat 
 smaller than the hole through which it passes. Proper valves are placed upon the pipes 
 connected with the gasometer pump, whereby the air drawn from the bottom compart- 
 ment is prevented from returning thither. A small forcing-pump is employed to raise 
 
 * Kriapp, Annal. dor Chem. und Pharm. xlii. 113. 
 
ACETIC ACID. 
 
 3 
 
 the liquor continually from the bottom of the tun to the cistern overhead. By this 
 arrangement good vinegar may be made in a few days, without any perceptible loss of 
 materials. The progress of the acetification in this apparatus is ascertained by testing 
 the air for oxygen as it is slowly drawn into the gasometers, or expelled from them. 
 For this purpose a bundle of twine, which has been impregnated with solution of sugar 
 of lead, and dried, is set fire to, and plunged into a bottle filled with the air. In 
 general, it is so well disoxygenated and carbonated, that the ignition is immediately 
 extinguished. By regulating the warmth of the apartment, the motion of the 
 gasometer, and the admission of air, the due progress of the acetification may be 
 secured. The vinegar has an average strength of 5^ per cent, of acetic acid hydrate, 
 and is immediately ready for the market. 
 
 Hitherto it has been generally imagined that the formation of vinegar is accom- 
 plished by a peculiar fermentation, which has been called the acetous, in contradistinc- 
 tion from the vinous, the panary, the putrefactive, &c. But this doctrine is doubtful. 
 The experiments which serve as its base, and which should reveal the nature of its pe- 
 culiar ferment, as also the chemical reactions which take place in its progress, all 
 seem to place this phenomenon somewhat out of the sphere of fermentation properly 
 so called. Every fermentation operates by resolving a body into compounds less com- 
 plex than itself. But the so-called acetic fermentation serves to combine, on the con- 
 trary, two bodies, viz. alcohol and aldehyde, with the oxygen of the air ; and this 
 is the only case where fermentation produces such an action, which is a true com- 
 bustion. 
 
 Yet it must be confessed that the acetic seems to possess all the characters of the 
 other fermentations ; namely, the union of an organised body or ferment with a fer- 
 mentable organic matter. The former is found in that mucous substance called mother 
 of vinegar, and which is seen floating on the surface of vinegar in the act of its gene- 
 ration. It begins to appear with the acid fermentation, and it continues to be formed 
 during its whole progress. It is at first a pellicle composed of globules much more 
 minute than those which constitute yeast ; and they are often irregularly grouped. 
 The pellicle becomes afterwards thicker in body and consistence, exhibits more distinct 
 granular forms, and acquires a tendency to be distributed in stripes or narrow bands. 
 The mode of the reproduction of these globules is quite unknown; but they seem 
 somewhat akin to the slimy deposit of sulphureous mineral waters called baregine. 
 
 If the study of the acetic ferment be mysterious, it is, however, clear that the conver- 
 sion of alcohol into vinegar never takes place in the common process without the pre- 
 sence of an albuminous substance, and of the conditions favourable to all fermentations, 
 besides the necessary access of air, not only at the commencement (as suffices for the 
 vinous) but during all its course. Hence every weak spirituous liquor which contains 
 an albuminous matter or any ferment may, with contact of air, and a temperature of 
 from 60° to 90° F., give birth to vinegar. If the mixture be too rich in alcohol, or 
 if the azotised matter be absent, or if the temperature be much above or below these 
 two points, the phenomenon of acetification stops. There are, therefore, several indi- 
 cations of the existence of a peculiar vinegar fermentation ; though it should be 
 observed that the production of lactic acid (as from fermenting cabbage, starch, &c.) 
 has sometimes misled chemists into the belief of an acetic fermentation. I shall, on 
 this account, point out here briefly the distinction between the two processes. 
 
 The acetic fermentation requires the presence of ready formed alcohol and of the 
 air ; the lactic, on the contrary, proceeds with starchy or saccharine mixtures, without 
 the intervention of alcohol or of atmospheric oxygen ; and when once begun, it will 
 go on of itself. The acetifying process presents, moreover, a striking analogy with 
 the phenomenon of nitrification, in the necessity of an elevated temperature and the 
 influence of porous bodies to divide the particles of the liquids and the air. Thus 
 gaseous ammonia mixed with oxygen, when passed through a tube containing spongy 
 platinum slightly heated, becomes nitric acid ; when sulphurous acid gas and oxygen 
 are passed through hot pumice-stone they become sulphuric acid ; and when lime or 
 potash, diffused through porous matter, is placed in contact with ammoniacal emana- 
 tions, in the artificial nitre beds, or nitrifiable soils, nitrate of lime or potash is formed. 
 In like manner, under the influence of spongy platinum, alcohol (OH 4 0 + H 2 0) and 
 air may, by a true oxidisement of the ethereous part of the alcohol (C 4 H 4 0) produce 
 aldehyde (C 4 H-»O l2 ), which passes afterwards into acetic acid (OH 3 0 3 + water, HO). 
 On these principles we may conceive that vinegar must be readily formed when 
 alcoholic wash, at a proper temperature, is extensively exposed to atmospheric air, by 
 being spread over the surfaces of wooden twigs, or chips in the German graduators. 
 In some districts cyder is rapidly acetified by being made to trickle cautiously along 
 strings suspended vertically between two vats. See Acetic Acid and Graduator in 
 the Dictionary. 
 
 B 2 
 
4 
 
 ALCOHOL. 
 
 AGRICULTURAL CROPS, composition of, by M. Boussingault. 
 C/iim. et Phys. III. S. p. 234. 
 
 Ann. Je 
 
 
 
 Ashes inclusive- 
 
 Exclusive of Ashes. 
 
 Substances. 
 
 
 o 
 a 
 
 g 
 
 to 
 o 
 
 • 
 
 3 
 to 
 
 CD 
 O 
 
 3 
 
 3 
 
 c 
 
 . 
 
 S 
 
 s° 
 
 >> 
 
 6 
 o 
 
 
 
 b 
 
 4 
 
 .. 
 
 •3 
 >a 
 
 33 
 
 >. 
 
 X 
 
 O 
 
 N 
 < 
 
 < 
 
 
 Hydi 
 
 X 
 
 o 
 
 M 
 < 
 
 Wheal - 
 
 - 
 
 46*1 
 
 5*8 
 
 43 "4 
 
 2*3 
 
 2*4 
 
 47*2 
 
 6-0 
 
 44*4 
 
 2 '4 
 
 Rye 
 
 
 46*2 
 
 5 '6 
 
 44*2 
 
 1*7 
 
 2'3 
 
 47-3 
 
 5*7 
 
 45*3 
 
 1*7 
 
 Oats 
 
 
 50*7 
 
 6*4 
 
 36*7 
 
 2 - 2 
 
 4*0 
 
 52*9 
 
 6-6 
 
 38*2 
 
 2'3 
 
 AVheat straw 
 
 
 48 "4 
 
 5*3 
 
 38 - 9 
 
 0*4 
 
 7'0 
 
 52*1 
 
 5-7 
 
 41-8 
 
 04 
 
 Rye straw 
 
 
 49-9 
 
 o o 
 
 40*6 
 
 0*3 
 
 3*6 
 
 51 "8 
 
 5-8 
 
 42-1 
 
 0 3 
 
 Oat straw 
 
 
 50-1 
 
 5 4 
 
 39-0 
 
 0-4 
 
 5-1 
 
 52 8 
 
 5-7 
 
 41-1 
 
 04 
 
 Potatoes - 
 
 
 44-0 
 
 5-8 
 
 44-7 
 
 1-5 
 
 4-0 
 
 45-9 
 
 6*1 
 
 46-4 
 
 1*6 
 
 Beetroot (field) - 
 
 
 42-8 
 
 58 
 
 43-4 
 
 1*7 
 
 6-3 
 
 45-7 
 
 6'2 
 
 46-3 
 
 1-8 
 
 Turnips - 
 
 
 42-9 
 
 5*5 
 
 42-3 
 
 1-7 
 
 :-6 
 
 46-3 
 
 60 
 
 45-9 
 
 1*8 
 
 Jerusalem artichokes 
 
 
 43-3 
 
 5-8 
 
 43-3 
 
 1-6 
 
 6-0 
 
 46-0 
 
 6-2 
 
 46-1 
 
 1-7 
 
 Yellow peas 
 
 
 46-5 
 
 6-2 
 
 40 0 
 
 4-2 
 
 3-1 
 
 48-0 
 
 6-4 
 
 41-3 
 
 4 3 
 
 Pease straw 
 
 
 45-8 
 
 5-0 
 
 35-6 
 
 2-3 
 
 11-3 
 
 51-5 
 
 5'6 
 
 40-3; 2-6 
 
 Red trefoil hay - 
 
 - '47-4 
 
 5-0 
 
 37-8 
 
 2-1 
 
 7-7 
 
 51-3 
 
 5-4 
 
 41-1 
 
 2-2 
 
 Jerusalem artichoke stems 
 
 45-7 
 
 5'4 |45-7 
 
 0-4 
 
 2-8 
 
 47-0 
 
 56 
 
 47-0 
 
 04 
 
 ALCOHOL, as obtained by the distillation of wine, of fermented corn wort, or 
 potato syrup, possesses different flavours, which arise from what the Germans call 
 Fusel oil, and which oil differs in those several spirituous liquors. That of wine has 
 been called Onanthic ether. It is resolvable into ether (oxide of ethal), and a peculiar 
 fatty acid, the Onanthic. 
 
 The oenanthic ether of corn spirit contains an additional oil, called corn oil, which 
 lias a most offensive smell. The potato fusel oil differs from that obtained from grain 
 spirit. It has, at the first impression, in its pure state, a strong, not disagreeable 
 smell, which afterwards becomes extremely nauseous, and excites an acrid burning 
 taste. The inhalation of its vapour causes a feeling of oppression, and vomiting. 
 All these fusel oils are readily soluble in alcohol, but not in water, whence, when 
 poured into the latter, they make a milky mixture. The potato fusel oil contains no 
 solunine from the potatoes, as has been alleged, though this noxious principle exists in 
 all potatoes, especially after germination. It is not a volatile product. 
 
 Corn damaged by rain in harvest time affords, after mashing and fermentation, 
 a most offensive fusel oil, which irritates the eyes and nostrils, and smells like a solu- 
 tion of cyanogen in alcohol. Spirits so contaminated intoxicate more powerfully than 
 purer spirits, and are apt to bring on temporary madness and subsequent indisposi- 
 tion. This noxious substance does not combine with gases ; and, being more volatile 
 than alcohol, it may be drawn off by distillation in a concentrated state. It is sepa- 
 rated to a considerable degree in Germany by diluting the foul spirits with water, 
 mixing in a portion of olive or other bland oil, letting the oil gather on the top, draw- 
 ing off the spirituous liquor from below, and subjecting it to rectification. When the 
 spirit so rectified is kept for 2 or 3 months in a cask, corked, but not too closely, the 
 noxious oenanthic compound disappears, in some measure by its spontaneous decompo- 
 sition. For statistics and Excise-proof table, see Spirits. 
 
 The high price of alcohol in this country, in consequence of the heavy fiscal duties, 
 and its low price in most other countries, where it is nearly duty free, has led to its 
 contraband importation under various disguises. Sometimes it is introduced under the 
 mask of oil of turpentine, from which it can be sufficiently freed by rectification for the 
 purpose of the gin manufacturers. Sometimes it is disguised with wood naphtha, or 
 wood vinegar ; from the latter of which it may be separated by distillation in a water 
 bath ; but from the former it is more difficult to extricate it, as alcohol and wood spirit 
 are nearly equally volatile. It has also been disguised with coal naphtha ; but from 
 this it may be easily separated by distillation, on account of the great difference be- 
 tween the boiling points of the two liquids ; besides, coal naphtha will not combine 
 with water, as alcohol does. 
 
 When the object is to discover whether wood spirit contains alcohol, we may pro- 
 ceed as follows : — Add to the suspected liquid a little nitric acid, of specific gravity 
 1 -45. If alcohol be present, in even small proportions, an effervescence will ensue, 
 from the evolution of etherised nitrous gas, with its characteristic ethereous smell. 
 On treating the mixture with a nitrous solution of mercury, as in the process for ful- 
 minate of mercury, an effervescence will take place, the dense vapour of etherised mer- 
 
 t > l 97 f <? 4 
 
 TT / // 
 
 A 
 
 '/vet i • tii i- 
 
ALUM. 
 
 5 
 
 curia! gas will appear, and a certain proportion of fulminate will be formed, corre- 
 sponding pretty closely to the proportion of alcohol in the wood naphtha mixture. 
 
 As the boiling point of wood spirit is only about 145°, while that of alcohol, of 
 like specific gravity (0-825), is 173° F., a good criterion of the proportion of the two 
 liquids present in the mixture may be found in its boiling temperature. 
 
 Pure wood spirit, when mixed with the above nitric acid, becomes of a ruby tint, 
 but remains tranquil. Alcohol continues colourless, but enters into violent ebullition, 
 and is nearly all dissipated in fumes. 
 
 Alcohol diluted with water has a less resultant density than wood spirit of like 
 strength similarly diluted. While alcohol thus becomes of 0*920, wood spirit becomes 
 0*926 or 0-927. 
 
 If wood spirit be contained in alcohol, it may be detected to the greatest minute- 
 ness by the test of caustic potash, a little of which, in powder, causing wood spirit to 
 become speedily yellow and brown, while it gives no tint to alcohol. Thus 1 per cent, 
 of wood spirit may be discovered in any sample of spirits of wine. For further de- 
 tails upon this analytical inquiry, see my pamphlet, entitled The Revenue in Jropardy. 
 
 ALG AUOV1LLA. This substance is called by the Spaniards Algaroba, from the 
 resemblance it bears to the fruit of the Carob ( Cerutonia siliqiia), which is a native of 
 Europe, in the southern countries of Spain and Portugal. The substance lately ana- 
 lysed by me is the fruit of a tree which grows in Chile, of which the botanical name is 
 Prosopis pallida, according to Captain Bagnald, R.N., who first brought a sample of 
 it to this country in the year 1832. It consists of pods bruised and agglutinated more 
 or less with the extractive exudation of the seeds and husks. According to a more 
 recent determination, algarovilla is said to be the product of the tree Juga Martha; 
 of Santa Martha, a province of New Carthagena. 
 
 It is an astringent substance replete with tannin, capable, by its infusion in water, of 
 tanning leather, for which purpose it possesses more than four times the power of good 
 oak bark. Its active matter is very soluble in water at a boiling temperature. The 
 seeds are merely nutritive and demulcent, but contain no astringent property. This 
 resides in the husks. The seeds in the entire pod constitute about l-5th of the weight, 
 and they are three or four in number in each oblong pod. Alcohol of 60 per cent, over 
 proof dissolves 64 parts in 100 of this substance. The solution consists chiefly of tan- 
 nin, with a very little resinous matter. Water dissolves somewhat more of it, and 
 a fiords a very styptic-tasted solution, which precipitates solution of isinglass very co- 
 piously, like infusion of galls and catechu. Its solution forms with sulphate of iron a 
 black precipitate, which is kept floating by means of the gum present, and thereby 
 constitutes good ink. My report to the merchant was written with a combination thus 
 made, in proportions taken at random ; and there is no doubt that by using a stronger 
 decoction of the algarovilla. along with a proper proportion of copperas, an excellent 
 black ink might be prepared without any other addition. 
 
 I find that a decoction of the algarovilla affords with cotton cloth, mordanted with 
 tin solution, as also with acetate of alumina liquor, a brilliant yellow die ; the former 
 being the brighter and fuller of the two. 
 
 A tincture of algarovilla might be used as an astringent in medicine ; or probably 
 a decoction of the whole substance would be preferable, on account of the demulcent 
 quality of the seeds when bruised. As an article of commerce it cannot be rated at a 
 high price, nor should it pay much duty till its value as an article of manufactures or 
 medicine be fully ascertained. 
 
 ALMONDS. Imported in ] 839, 28,261 cwt. ; in 1840, 27,566. Retained for 
 consumption, 9785 and 7935, respectively. 
 
 ALUM. In the alum works on the Yorkshire coast. 8 different liquors are met with. 
 
 1st. " Raw Liquor." The calcined alum shale is steeped in water till the liquor 
 has acquired a specific gravity of 9 or 10 pennyweights, according to the lan- 
 guage of the alum-maker. 
 
 2d. "Clarified Liquor." The raw liquor is brought to the boiling point in lead 
 pans, and suffered to stand in a cistern till it has cleared : it is then called clari- 
 fied liquor. Its gravity is raised to 10 or 11 pennyweights. 
 
 3d. " Concentrated Liquor." Clarified liquor is boiled down to about 20 penny- 
 weights. This is kept merely as a test of the comparative value of the potash 
 salts used by the alum-maker. 
 
 4th. " Alum Mother Liquor." The alum pans are fed with clarified liquor, which 
 is boiled down to about 25 or 30 pennyweights, when a proper quantity of pot- 
 ash salt in solution is mixed with it, and the whole run into coolers to crvstal- 
 lise. The liquor pumped from these rough crystals is called "alum mothers." 
 
 5th. " Salts Mothers." The alum mothers are boiled down to a crystallising 
 point, and afford a crop of " Rough Epsom," which is a sulphate of magnesia 
 and protoxide of iron. 
 
6 
 
 ALUM. 
 
 6th and 7th. " Alum Washings." The rough crystals of alum (No. 4.) are 
 washed twice in water, the first washing being about 4 pennyweights, the second 
 about 2i, the difference in gravity being due to mother liquor clinging to the 
 crystals. 
 
 8th. " Tun Liquor." The washed crystals are now dissolved in boiling water, and 
 run into the "roaching tuns "(wood vessels lined with lead) to crystallise. The 
 mother liquor of the " roach alum" is called " tun liquor :" it is, of course, not 
 quite so pure as a solution of roach alum in water. 
 The alum-maker's sp. gr. bottle holds 80 penny weights of water, and by 10 penny- 
 weights he means 10 more than water, or 90. 
 
 The numbers on Twaddle's hydrometer, divided by 2-5, give alum-maker's penny- 
 weights. 
 
 The alum-maker tests his samples of potash salts comparatively by dissolving equal 
 weights of the different samples in equal measures of alum liquor at 20 pennyweights, 
 heated up to the boiling point, and weighing the quantity of alum crystals produced 
 on cooling. 
 
 For the above information I am indebted to my friend Mr. Maurice Scanlan, who 
 superintended for some time the Mulgrave alum works. 
 
 He informs me that 61^ tons of the alum rock at the Mulgrave Works to the north 
 of Whitby, yield, after calcination, &c. one ton of alum. 
 
 It has been computed that with sulphur at 61. per ton, sulphuric acid of spec. grav. 
 1 '750 can be produced at 31. per ton, including the mere cost of making : this acid 
 contains 2 atoms of water : 174 tons of this acid, and 87 \ tons of sulphate of potash, 
 with the pipe-clay, will form 474 tons of alum ; so that the neat cost would be 522/. 
 for the acid + 1047Z. for the sulphate of potash, = 15691. ; which sum, divided by 474, 
 gives a quotient of 31. 6s. for the neat cost of 1 ton of alum by the direct process. 
 
 At the pit 1 ton of alum — rock or mine, costs 3/. 4s. ; to which, adding the cost of the 
 potash salt for 1 ton of alum, 3/. 15s., they constitute together an amount of 61. 19s. 
 From the latter sum 11. 10s. must, however, be deducted for the value of rough Epsom 
 salt produced, leaving a balance of 51. 9s. for the cost of a ton of mine-alum, prior to 
 evaporation and crystallization. 
 
 A patent was obtained in November, 1839, by Mr. William Wiesmann, of Dues- 
 burg, for improvements in the manufacture of alum. He subjects potter's clay to a 
 moderate red heat, grinds it, and subjects the powder, in leaden pans, to the action of 
 concentrated sulphuric acid (66° Beaume), taking care to use excess of clay and a 
 moderate heat. This mixture is to be stirred till it is dry, then treated with boiling 
 water, in order to dissolve the sulphate of alumina formed. So far the process is old 
 and well-known. The novelty consists in freeing the saline solution from iron by 
 ferrocyanure of potassium (prussiate of potash). When the iron has been all thrown 
 down in the form of prussian blue, the liquor is allowed to settle, the supernatant pure 
 sulphate is drawn off, and evaporated till it forms on cooling a concrete mass, which 
 may be moulded into the shape of bricks, &c, for the convenience of packing. He 
 proposes to crystallise his alum ; but he will find this process rather difficult. The 
 prussian blue obtained may be reconverted by any alkaline solution into a ferrocyanide, 
 and again employed on a fresh quantity of the raw sulphate. How he is to precipitate 
 the iron by sulphate of lime, as he states, I cannot comprehend. 
 
 Dr. Turner's process for making alum from felspar is thus described by him in 
 the specification of his patent, sealed October 8. 1842. If it be desired to make 
 a potash alum, the best substance to operate upon is a potash felspar. This felspar 
 is ground in a common edge-stone mill to the consistency of fine sand (a process 
 which is much assisted by first heating it to redness, and then plunging it in cold 
 water) ; it is then mixed with its own weight of sulphate of potash, and placed in the 
 upper part of the inclined bed of a reverberatory furnace (being such a furnace as is 
 known in the potteries as a frit furnace), and which furnace has previously been 
 brought to a full white heat. When by the action of the heat a glass has been pro- 
 duced, and is observed to flow down the inclined bed of the furnace, to such glass is to 
 be added gradually, at the lower end of the furnace, as much carbonate of potash as 
 was before used of sulphate of potash. And this process of placing the mixture of 
 felspar and sulphate of potash at the upper part of the bed of the furnace is to be 
 repeated, adding at the lower part of the bed, gradually and proportionally, as the 
 glass flows down from the upper part, the carbonate of potash, as before mentioned. 
 This is continued until the sack of the furnace is filled with the glass ; this glass is then 
 fit for the next process. The preparation of the glass may also be effected in a 
 reverberatory furnace with a flat bed ; and the facility of removing the glass from such 
 a furnace is an advantage. In this case no carbonate must be added to the mixture 
 until the sulphate of potash is observed to be completely decomposed. On boiling in 
 water the glass thus obtained, the same quantity of potash as was added to the felspar 
 
ANCHOVIES, ESSENCE OF. 
 
 7 
 
 and two thirds of the silica contained in the felspar are dissolved, while the remaining 
 one third of the silica and the alumina, and an equal quantity of potash as the felspar 
 originally contained, are left in the form of a light porous substance, similar in 
 chemical composition to the mineral commonly called ela?olite ; this porous substance 
 is carefully separated from the said solution, and washed with water until freed from 
 the silicate of potash, then placed in an open leaden cistern or boiler, and boiled with 
 dilute sulphuric acid of the specific gravity 1*2 (one and two-tenths). This acid will 
 contain about the quantity of water required for the solution and crystallization of the 
 alum produced by the decomposition of the ela?olite ; the quantity of the dilute 
 sulphuric must be such as will contain about 160 lbs. of dry sulphuric acid for every 
 285 lbs. of felspar rock (if that rock be used), and in like proportion to the silica and 
 alumina contained in the substance, if any other substance be used, as it is important 
 that the alum solution thus obtained should not contain an excess of acid. I 
 recommend that only four-fifths of the proposed quantity of dilute sulphuric acid 
 should be used in the first operation, which will leave a portion of the elaxdite 
 undecomposed ; but by acting upon this undecomposed portion, after the solution has 
 been drawn off, with the full quantity of dilute acid to be used in the next operation, 
 it will be completely decomposed, and the alum thus formed becomes part of the next 
 batch. In this way a neutral solution of alum is obtained at each process. The 
 boiling solution, after the sediment subsides, is drawn into coolers, such as are com- 
 monly used for the crystallization of alum; here about four-fifths of the alum held in 
 solution will form into crystals. The mother liquor from the coolers is boiled in any 
 convenient boiler to dryness, in order to render the silica it contains insoluble ; the 
 residuum is boiled either in water or in the mother-liquor from the roaching tubs, so 
 as to dissolve the alum it contains, and the process of crystallization repeated. Had 
 the above process been performed with the salts of soda instead of potash, a soda alum 
 would have been formed. For this purpose the soda felspar or albite should be 
 selected. The potash or soda (as the case may be) contained in the liquor, 
 drawn as aforesaid from the elaeolite (or nepheline, which is formed when soda is 
 used), may be recovered by either of the following processes : — The strong solu- 
 tions which are obtained, about the specific gravity of 1 *2 are placed in any 
 convenient vessel in which a stream of carbonic acid gas, obtained in any convenient 
 method, may be driven through them, the carbonic acid becomes absorbed, and the 
 solution assumes the form of a gelatinous mass : this mass consists of carbonate of 
 potash or soda and hydrate of silica. On drying this mass in a furnace, which must 
 never be allowed to rise to red heat even in the dark, the silica loses its water and 
 becomes insoluble ; the potash or soda may then be separated from it in the form of a 
 sesquicarbonate of potash or soda, by solution and evaporation to dryness. The other 
 process, which under most circumstances will be found more economical and convenient, 
 is to allow the boiling solution of silicate of potash or soda to filter through a bed of 
 caustic lime, when it will be found that the lime has combined with the silicate, and 
 a caustic potash or soda ley is obtained. This process may be conveniently conducted in 
 an apparatus similar to that used by soap-makers for the preparation of their caustic leys. 
 The potash or soda may then be readily obtained as caustic potash or soda, or as car- 
 bonate, by the known processes used in making soda. The weak solutions of silicate 
 of potash or soda are used to decompose another portion of the glassy substance. 
 
 Now I do not claim as new, or as my invention, any particular form of vessel or 
 apparatus in which or with which my operations may be conducted ; nor do I claim any 
 particular proportions in which the alkaline salts may be used. But I claim as new, 
 and as my invention, the improvements aforesaid, and the production of substances 
 similar to elceolite and nepheline artificially, by the decomposition by water of the 
 glassy substances produced by the fusing of felspar as aforesaid, or other mineral sub- 
 stances containing silica and alumina, with salts of potash and soda, as aforesaid, and 
 the use and application of such artificial elasolite and nepheline in the production and 
 manufacture of alum, as aforesaid. I also claim the process, as above described, for 
 separating the alkalies from silica by means of caustic lime. 
 
 ANCHOVIES, ESSENCE OF. I insert this article to show on what slender 
 pretence of invention a patent may be obtained, Mr. John Masters, of Leicester, 
 makes his improved transparent preparation, by placing in a kettle any given quantity of 
 anchovies in the state in which they are imported, along with their own weight of 
 water, exposing the kettle to a simmering heat for two or three hours, removing the 
 kettle, and straining its contents when cold, first by suitable pressure through a strong 
 canvas bag, and next filtered through a flannel or paper till a clear liquor is obtained. 
 If it be desired to render the essence thicker, the material used for this purpose should 
 be transparent. He says that flour is used for thickening the common essence. 1 
 presume he would prefer gelatine, gum, or arrow root for his transparent thickening, 
 though he does not specify any thing. 
 
8 
 
 ARROW ROOT. 
 
 ANNOTTO or ANNATTO. Imported in 1839, 303,489 lbs. ; in 1840, 408,4G9. 
 Retained for consumption, 224,794 and 330,490, respectively. 
 
 ARCHIL has been lately the object of numerous chemical researches, but hitherto, 
 it must be owned, without producing any results useful to the dyer, so as to promote 
 the solidity of this beautiful and now cheap dye. The new experiments of Schunk, 
 performed in Liebig's laboratory, tend to show that the whole matter is still involved 
 in much mystery. By the action of ether on the Variolaria lactea (one of the archil 
 lichens), in an apparatus of displacement, he obtained crystals, which he calls lecanorine. 
 It is convertible into the orcine of Robiquet and Heeren by hot barytes water. When 
 moistened with water of ammonia, and exposed to the air, it gradually assumes the 
 archil tint. Liebig is of opinion, that this product, and some other analogous ones, 
 vary according to the nature of the solvents and the temperature of the digestions, so 
 that they probably are mere metamorphoses of the self-same one or two substances, 
 pre-existing in the lichens. Since lecanorine is decomposed by boiling water into 
 carbonic acid, and orcine, it may also undergo this change from the boiling alcohol em- 
 ployed in Sch unit's researches. 
 
 When ammonia acts upon orcine, it gives it a dark blood-red colour, and converts it 
 into orceine, a new compound containing azote, but in a different state of combination 
 from what it is in ammonia. This orceine is the true colouring matter of the archil or 
 orseille ; and, according to Robiquet, it is here in the state of an orceate of ammonia, 
 requiring for its production the co-operation of air and water. In these circumstances 
 the orceine absorbs oxygen, and is transformed into orceate of ammonia, without any 
 other product, even carbonic acid, being formed. Variolarine, erytkrine and pseudo- 
 erythrine, three products obtained by Robiquet and Heeren ; the first from* Vario'aria 
 dealbata, the second and third from Purmelia roccella, and Lecanora tartarea, are inte- 
 resting merely in a scientific point of view. The last two are transformed into red 
 colouring matters by ammonia and air. " Latterly," says Liebig, " Kane has made 
 these two substances objects of a particular investigation; but the researches of this che- 
 mist are far, as appears to me, from clearing up their history."* I need not, therefore, 
 give any account of these researches, which occupy a large portion of a recent volume 
 of the Philosophical Transactions. 
 
 I'ournesole, or litmus, consists, according to Peretti, of a red colouring matter, rendered 
 blue by combination with ammonia. 
 
 ARROW ROOT. This plant has been lately cultivated with great success, and 
 its root manufactured in a superior manner, upon the Hopewell estate, in the island of 
 St. Vincent. It grows there to the height of about 3 feet, and it sends down its tap 
 roots from 12 to 18 inches into the ground. Its maturity is known by the flagging 
 and falling down of the leaves, an event which takes place when the plant is from 10 to 
 12 months old. The roots being dug up with the hoe are transported to the washing- 
 house, where they are thoroughly freed from all adhering earth, and next taken indivi- 
 dually into the hand, and deprived by a knife of every portion of their skins, while 
 every unsound part is cut away. This process must be performed with great nicety, 
 for the cuticle contains a resinous matter, which imparts colour and a disagreeable 
 flavour to the fecula, which no subsequent treatment can remove. The skinned roots 
 are thrown into a large cistern, with a perforated bottom, and there exposed to the 
 action of a copious cascade of pure water, till this runs off quite unaltered. The 
 cleansed roots are next put into the hopper of the mill, and are subjected to the power- 
 ful pressure of two pairs of polished rollers of hard brass ; the lower pair of rollers 
 being set much closer together than the upper. (See the accompanying figure.) The 
 starchy matter is thus ground into a pulp, which falls into the receiver placed beneath, 
 and is thence transferred to large fixed copper cylinders, tinned inside, and perforated 
 at the bottom with numerous minute orifices, like a kitchen drainer. Within these 
 cylinders, wooden paddles are made to revolve with great velocity, by the power of a 
 water-wheel, at the same time that a stream of pure water is admitted from above. 
 The paddle-arms beat out the fecula from the fibres and parenchyma of the pulp, and 
 disehargc it in the form of a milk through the perforated bottom of the cylinder. 
 This starchy water runs along pipes, and then through strainers of fine muslin into 
 large reservoirs, where, after the fecula has subsided, the supernatant water is drawn 
 off, and fresh water being let on, the whole is agitated and left again to repose. This 
 process of ablution is repeated till the water no longer acquires any thing from the 
 fecula. Finally, all the deposits of fecula of the day's work are collected into one cis- 
 tern, and, being covered and agitated with a fresh charge of water, are allowed to settle 
 till next morning. The water being now let off, the deposit is skimmed with palette 
 knives of German silver, to remove any of the superficial parts, in the slightest degree 
 coloured; and only the lower, purer, and denser portion is prepared by drying for the 
 
 * Traite de Chimie Organiquc, torn. ii. p. 477. 
 
ARROW ROOT. 
 
 9 
 
 market. The drying-house on the Hopewell estate is constructed like the hot-house of 
 an English garden. Hut instead of plants, it contains ahout 4 dozen of drying pans 
 made of copper, 7^ feet hy 4^, and tinned inside. Each pan is supported on a car- 
 riage, having iron axles, with lignum vitas wheels, like those of a railway carriage, and 
 they run on rails. Immediately after sun-rise, these carriages with their pans, covered 
 with white gauze, to exclude dust and insects, are run out into the open air, hut if rain 
 he apprehended, they are run hack under the glazed roof. In ahout 4 days the fecula 
 is thoroughly dry and ready to he packed, with German silver shovels, into tins or 
 American flour barrels, lined with paper attached with arrow root paste. The packages 
 are never sent to this country in the hold of the ship, as their contents are easily 
 tainted by noisome effluvia, of sugar, Sec. By such a skilful series of operations, and 
 by such precautions, the arrow root thus manufactured may vie with any similar pre- 
 paration in the Bermudas or any other part of the world. I have found it, on analysis 
 and trial, to be pure, powerful, and agreeable, and a most wholesome article of food. 
 Fiff.l. Plan of arrow root grinding-mill, and of 2 sets of copper cylinder washing- 
 
10 
 
 ARTESIAN TVELLS. 
 
 machines, with the connecting machinery for driving them ; the washing agitator being 
 driven from the connecting shaft with leathern belts. Fig. 2. End elevation of arrow" 
 
 root mill, with wheels and pinions, disengaging lever, &c. Fig. 3. End elevation of 
 copper washing- cylinders, with press-framing, &c. The washing-cylinders are 6^ 
 feet long and 3| in diameter. The mill-rollers are 3 feet 
 3 long and 1 foot in diameter. 
 
 The uses of arrow root are too well known and acknow- 
 ledged to require recounting here. It is the most elegant 
 and the richest of all the feculas, and being now manu- 
 factured, with the advantage of excellent machinery, and 
 abundance of pure water, in the fertile island of St. Vincent, 
 it may be brought into our market at a much more mo- 
 derate price than it has heretofore been supplied from less 
 favoured localities. The Bermuda arrow root is treated 
 necessarily with rain water collected in tanks, and therefore 
 is occasionally soiled with insects, from which the St. Vin- 
 cent article is entirely free. 
 The presence of potato starch in arrow root may be discovered by the microscope. 
 Arrow root consists of regular ovoid particles of nearly equal size, whereas potato 
 starch consists of particles of an irregular ovoid or truncated form, exceedingly irre- 
 gular in their dimensions, some being so large as ^ of an inch, and others only 
 But the most convenient test is dilute nitric acid of 1 -10 (about the strength of single 
 aquafortis), which, when triturated in a mortar with the starch, forms immediately a 
 transparent very viscid paste or jelly. Flour starch exhibits a like appearance. Arrow 
 root, however, forms an opaque paste, and takes a much longer time to become viscid. 
 (Dr. Scharling in Liebig's Annalen.) 
 
 Arrow root may be distinguished from potato starch, not only by the different size 
 of its particles, but by the difference of structure. Their surfaces in the arrow root 
 are smooth, and free from the streaks and furrows seen in the potato particles by a 
 good microscope. The arrow root, moreover, is destitute of that fetid unwholesome 
 oil, extractable by alcohol from potato starch. 
 
 Liebig places the powers of arrow root, as a nutriment to man, in a very remark- 
 able point of view, when he states that 15 pounds of flesh contain no more carbon for 
 supplying animal heat by its combustion into carbonic acid in the system, than 4 
 pounds of starch ; and that if a savage, with one animal and an equal weight of starch, 
 could maintain life and health for a certain number of days, he would be compelled, if 
 confined to flesh alone, in order to procure the carbon necessary for respiration, during 
 the same time, to consume five such animals. 
 
 Arrow root imported in 1839, 303,489; in 1840, 408,469 lbs. ; retained for con- 
 sumption, 224,794 and 330,490 respectively. 
 
 ARTESIAN "WELLS. Fig. 4.* represents the manner in which the condensed 
 water of the heavens distributes itself under the surface of our globe. Here we have 
 a geological section, showing the succession of the several formations, and the sheets or 
 laminae of water that exist at their boundaries, as well as in their sandy beds. The 
 figure shows also very plainly that the height to which the water reascends in the 
 bore of a well, depends upon the height of the reservoir which supplies the sheet of 
 water to which the well is perforated. Thus the two wells a, a, having gone down to 
 
 * At the end of the Volume. 
 
ARTESIAN WELLS. 
 
 11 
 
 the two aqueous expanses below, whose respective waters of supply are derived from 
 the percolations ai a' and m b', will afford rising waters, which will come to the sur- 
 face ; whilst in the well b, supplied by the sheet p, cJ, d', the waters will spout above the 
 surface, and in the well c they will remain short of it. The same figure shows that 
 these wells often traverse sheets of water that rise to different heights. Thus in the 
 well c, there are five columns of ascending waters, which rise to heights proportional 
 to the points whence they take their origin. Several of these will be spouting or over- 
 flowing, but some will remain beneath the surface. 
 
 Nofient. Bar sur- 
 
 Faris. Provins. sur Seine. Troyes. Lusigny. Seine. 
 
 4 
 
 The older geological formations are seldom propitious to the construction of Arte- 
 sian wells, on account of the compact massiveness of their rocks, of the few fissures 
 or porous places in them, and of the rarity of filtering strata overlying retentive ones. It 
 is therefore vain to attempt the formation of an overflowing spring, upon the above prin- 
 ciples, in territories of granite, gneiss, mountain limestone, and basalt. Among transition 
 and secondary formations, such wells will rarely furnish a supply of good water. The 
 latter strata of alternating clay and variegated sandstone contain so much gypsum and 
 rock salt as to impregnate therewith the waters derived from them to an unpalatable 
 degree. It is in the sandy, calcareous, and argillaceous strata of the Jura limestone, 
 indeed, that borings may most probably be made for brine springs. The hot springs 
 which burst out of the ground in primitive rocky districts come undoubtedly from a 
 great depth under the surface, and derive their temperature, and also probably their 
 waters, from the vapours of deep-seated volcanoes in connection with the sea. A miniature 
 representation of such springs is exhibited in the intermitting fountains of fresh water 
 on the shoulder of Vesuvius. Springs of this kind, which vary with the seasons, may de- 
 rive a portion of their water from the surface of the earth, from which it may sink through 
 clefts in the primitive rocks, till meeting in its descent with stony obstructions and ascend- 
 ing steam, it is forced to remount in a heated state to the day, like the Geisers in Iceland. 
 The most remarkable example of an Artesian well is that recently formed at Grenelle, 
 a- suburb at the south-west of Paris, where there was a great want of water. It cost 
 eight years of difficult labour to perforate. The geological strata round the French 
 capital are all of the tertiary class, and constitute a basin, like that shown in fig. 4. 
 The bottom of this basin is chalk ; a a are tertiary strata above the chalk ; b b, chalk 
 or cretaceous carbonate of lime ; c c, n d, green sand and clay ; e e, oolite and Jura 
 limestone (muschelkalk) ; e a, general slope of the surface of the country from Langres 
 to Paris ; m a, the level of the sea. Over a circular space, of which Paris is the centre, 
 and which is bounded by the towns of Laon, Mantes, Blois, Sancerre, Nogent-sur- 
 Seine, and Epernay, these strata are found upon the surface, concealing the chalk ; but 
 on the other side of these towns, the edge of the basin being passed, the chalk is gene- 
 rally the superficial bed. By looking at the order of these tertiary strata, it is easy 
 to perceive the obstacles that M. Malot, the engineer of the well, had to overcome, and 
 the difficulty and hazard of his undertaking. The surface at Grenelle consists of 
 gravel, pebbles, and fragments of rock, which have been deposited by the waters at 
 some period anterior to any historical record. Below this layer of detritus, it was 
 known to the engineer, by geological induction, as well as previous experience, that at 
 Grenelle, marl and clay would be found, instead of the limestone which generally forms 
 the immediately subjacent stratum. He was aware that he had to bore about 440 
 yards! deep before he should arrive at the sheet of water (s, figure) which flows 
 in the gravel below the limestone, and supplies the wells of St. Ouen, St. Denis, and 
 Stains. Underneath the marl and the clay, the boring rods had to perforate pure 
 gravel, plastic clay, and finally chalk, which forms the bottom of the general tertiary 
 basin, as we have seen. No calculation from geological data could determine the 
 thickness of this stratum of chalk, which, from its powers of resistance, might present 
 an almost insuperable obstacle. The experience acquired in boring the wells of 
 
 C 2 
 
12 
 
 ARTESIAN WELLS. 
 
 Elbeuf, Rouen, and Tours was in this respect but a very imperfect guide. But sup- 
 posing this obstacle to be overcome, was he sure of finding a supply of water beloAv 
 this mass of chalk ? In the first place, the strata c d below the chalk possessed, as we 
 shall see, all the necessary conditions for producing Artesian springs, namely, succes- 
 sive layers of clay and gravel, or of pervious and impervious beds. M. Malot con- 
 fidently relied on his former experience of the borings of the wells at Rouen, Elbeuf, 
 and Tours, where abundant supplies of water had been found below the chalk, be- 
 tween similar strata of clay and gravel. 
 
 But one other condition is requisite to ensure the rising of the water in an Artesian 
 well, namely, that the feeding level of infiltration should be higher than the orifice in 
 the bore above which the water is to ascend. This, however, turned out to be the case 
 with Grenelle. M. Arago had shown that the water of the spring here would neces- 
 sarily rise to the surface, because in the well at Elbeuf, which is nearly 9 yards above 
 the level of the sea, the water rises from 27 to 29 yards above the surface of the earth, 
 and, consequently, from 36 to 38 yards above the ocean level. Now, as the orifice of 
 the bore at Grenelle is only 34 yards above the same level, it follows, that if the iden- 
 tical spring be met with, the water must rise above the earth's surface at Grenelle. 
 
 The necessary works were commenced with boring rods about 9 yards long, attached 
 to each other, and which could be raised or lowered by mechanical power, while an 
 ingenious method was adopted for giving them a rotary motion. The diameter of 
 the bore was about 6 inches. The instrument affixed to the end of the lowest boring 
 rod was changed according to the different strata which were successively attacked ; 
 the form suited for passing through the softer materials near the surface being unsuit- 
 able for boring through the chalk and flint, as a hollow tube was used for the former, 
 while a chisel-shaped tool was employed to penetrate the latter. The size of the rods 
 was lessened as the depth increased ; and, since the subterranean water was not reached 
 so soon as was expected, it became requisite to enlarge five several times the diameter 
 of the bore, in order to permit the work to be successfully prosecuted. Accidents oc- 
 curred which tried the patience of the projectors. In May, 1837, when the boring had 
 extended down to a depth of 418 yards, the hollow tube, with nearly 90 yards of the 
 long rods attached to it, broke, and fell to the bottom of the hole, whence it became 
 necessary to extract the broken parts before any further progress could be made. The 
 difficulty of accomplishing this task may be conceived; for the different fragments were 
 not all extracted until after the constant labour of 15 months. Again, in April, 
 1840, in passing through the chalk, the chisel attached to the boring rod got detached, 
 and before it could be recovered, several months were spent in digging round about it. 
 A similar occurrence created an obstacle which impeded the work for 3 months, 
 but, instead of withdrawing the detached part, it was forcibly driven down among the 
 stratum of gravel. At length, in February, 1841, after 8 years' labour, the rods 
 suddenly descended several yards, having pierced into the vault of the subterranean 
 waters so long sought after by the indefatigable engineer. A few hours afterwards, he 
 was rewarded for all his anxious toils ; for lo ! the water rose to the surface, and 
 discharged itself at the rate of 600,000 gallons per hour ! 
 
 The depth reached down was 602 yards, or about three times the height of St. Paul's. 
 The pipe by which the water reaches the surface has been recently carried to a height 
 nearly level with the source of supply. The portion of the pipe above the ground is 
 surrounded with a monumental pagoda of ornamental carpentry, and it discharges a 
 circular cascade of clear water continually into a circular iron reservoir, to be thence 
 conveyed by a lateral pipe to the ground. The water is well adapted for all domestic 
 uses, and it will be unfailing, being supplied from the infiltration of a surface of coun- 
 try nearly 200 miles in diameter. The Artesian wells of Elbeuf, Rouen, and Tours, 
 which were formed many years ago, overflow in never varying streams ; and the an- 
 cient Artesian well at Lillers, in the Pas de Calais, has for about seven centuries fur- 
 nished a constant and equable supply. 
 
 The opportunity of ascertaining the temperature of the earth at different depths, was 
 not neglected during the progress of the works at Grenelle. Thermometers placed at 
 a depth of thirty yards in the wells of the Paris Observatory invariably stand at 53° 
 Fahrenheit. In the well at Grenelle the thermometer indicated 74° F. at a depth of 
 442 yards, and at 550 yards it stood at 79°. At the depth finally arrived at of 602 
 yards, the temperature of the water which rose to the surface was 81°, corroborating 
 previous calculations on the subject. For a descent of 572 yards there is an increase of 
 temperature equal to 28° F., Avhich is 20*4 yards, or 61*2 feet for each degree of that 
 scale. Now that the skilful labour of so many years is terminated, the Parisians re- 
 gret that the subterranean sheet of water had not lain 1000 yards beneath the surface, 
 that they might have had an overflowing stream of water at 104°, to furnish a cheap 
 supply to their numerous hot-bath establishments. 
 
 ASPH ALTIC PAVEMFNT ; see Bitumen. 
 
BEER. 
 
 13 
 
 B. 
 
 BALSAM OF C A PI VI, or Copaiva Balsam. This substance, which is extensively 
 used in medicine, is often adulterated. Formerly some unctuous oil was mixed with 
 it, but as this is easily discovered by its insolubility in alcohol, castor oil has since 
 been used. The presence of this cheaper oil may be detected, 1. by agitating the bal- 
 sam with a solution of caustic soda, and setting the mixture aside to repose ; when the 
 balsam will come to float clear on the top, and leave a soapy thick magma of the oil 
 below ; 2. when the balsam is boiled with water, in a thin film, for some hours, it will 
 become a brittle resin on cooling, but it will remain viscid if mixed with castor oil ; 
 3. if a drop of the oil on white paper be held over a lamp, at a proper distance, its vo- 
 latile oil will evaporate and leave the brittle resin, without causing any stain around, 
 which the presence of oil will produce ; 4. when three drops of the balsam are poured into 
 a watch-glass, alongside of one drop of sulphuric acid, it becomes yellow at the point of 
 contact, and altogether of a saffron hue when stirred about with a glass rod, but if 
 sophisticated with castor oil, the mixture soon becomes nearly colourless like white 
 honey, though after some time the acid blackens the whole in either case ; 5. if 3 parts 
 in bulk of the balsam be mixed with 1 of good water of ammonia (of O970 sp. grav. ) 
 in a glass tube, it will form a transparent solution, if it be pure, but will form a white 
 liniment if it contains castor oil ; 6. if the balsam be triturated with a little of the com- 
 mon magnesia alba, it will form a clear solution, from which acids dissolve out the mag- 
 nesia, and leave the oil transparent if it be pure, but opaque if it be adulterated. When 
 turpentine is employed to falsify the balsam, the fraud is detected by the smell on heat- 
 ing the compound. 
 
 BARILLA. Imported in 1841, 2131 tons; in 1842,2141. Retained for con- 
 sumption, 2369 and 2139, respectively. 
 
 BEER. The Germans from time immemorial have been habitually beer drinkers, 
 and have exercised much of their technical and scientific skill in the production of beer 
 of many different kinds, some of which are little known to our nation, while one at 
 least, called Bavarian, possesses excellent qualities, entitling it to the attention of all 
 brewers and consumers of this beverage. The peculiarities in the manufacture of Ba- 
 varian beer have recently attracted the attention of the most eminent chemists in Ger- 
 many, especially of Professor Liebig, and much new light has thereby been thrown 
 upon this curious portion of vegetable chemistry, which I shall endeavour to reflect 
 upon the present article. 
 
 The following is a list of the principal beers at present brewed in Germany. 
 
 1 . Brown beer of Merseburg ; of pure barley malt. 
 
 2. — — barley malt and beet-root sugar. 
 
 3. — barley malt, potatoes, and beet- root syrup. 
 
 4. — refined beet-root syrup alone. 
 
 5. Covent or thin beer. 
 
 6. Berlin white beer, or the Champagne of the north. 
 
 7. Broyhan, a famous Hanoverian beer. 
 
 8. Double beer of Griinthal. 
 
 9. Bavarian beer ; 1. Summer beer ; 2. Winter beer. 
 
 10. — Bock-beer. 
 
 11. Wheat Lager-beer (slowly fermented). 
 
 1 2. White bitter beer of Erlangen. 
 
 Considerable interest among men of science, in favour of the Bavarian beer process, 
 has been excited ever since the appearance of Liebig's Organic Chemistry, first pub- 
 lished about three years ago. In the introduction to this admirable work, he says, 
 " The beers of England and France, and the most part of those of Germany, become 
 gradually sour by contact of air. This defect does not belong to the beers of Bavaria, 
 which may be preserved at pleasure in half-full casks, as well as full ones, without al- 
 teration in the air. This precious quality must be ascribed to a peculiar process 
 employed for fermenting the wort, called in German vntergahrung, or fermentation 
 from below ; which has solved one of the finest theoretical problems. 
 
 " Wort is proportionally richer in soluble gluten than in sugar. * When it is set to 
 ferment by the ordinary process, it evolves a large quantity of yeast, in the state of a 
 thick froth, with bubbles of carbonic acid gas attached to it, whereby it is floated to the 
 surface of the liquid. This phenomenon is easily explained. In the body of the wort 
 along side of particles of sugar decomposing, there are particles of gluten being oxidized 
 
 * It dons not surely contain more gluten than it does sugar ; at least no experiments, known to me, 
 prove this proposition. 
 
14 
 
 BEEK, BAVARIAN. 
 
 at the same time, and enveloping as it were the former particles, whence the carbonic 
 acid of the sugar and the insoluble ferment from the gluten being simultaneously pro- 
 duced, should mutually adhere. When the metamorphosis of the sugar is completed, 
 there remains still a large quantity of gluten dissolved in the fermented liquor, which 
 gluten, in virtue of its tendency to appropriate oxygen, and to get decomposed, induces 
 also the transformation of the alcohol into acetic acid (vinegar). But were all the 
 matters susceptible of oxidizement as well as this vinegar ferment removed, the beer 
 would thereby lose its faculty of becoming sour. These conditions are duly fulfilled 
 in the process followed in Bavaria. 
 
 " In that country the malt- wort is set to ferment in open backs, with an extensive sur- 
 face, and placed in cool cellars, having an atmospheric temperature not exceeding 8° or 
 10° centigrade (46|° or 50° F. ). The operation lasts from 3 to 4 weeks; the carbonic 
 acid is disengaged, not in large bubbles that burst on the surface of the liquid, but in 
 very small vesicles, like those of a mineral water, or of a liquor saturated with carbonic 
 acid, when the pressure is removed. The surface of the fermenting wort is always in 
 contact with the oxygen of the atmosphere, as it is hardly covered with froth, and as 
 all the yeast is deposited at the bottom of the back under the form of a very viscid 
 sediment, called in German unterhefe. 
 
 " In order to form an exact idea of the difference between the two processes of fer- 
 mentation, it must be borne in mind that the metamorphosis of gluten and of azotized 
 bodies in general is accomplished successively in two principal periods, and that it is in 
 the first that the gluten is transformed in the interior of the liquid into an insoluble 
 ferment, and that it separates alongside of the carbonic acid proceeding from the sugar. 
 This separation is the consequence of an absorption of oxygen. It is, however, hardly 
 possible to decide if this oxygen comes from the sugar, from the water, or even from 
 an intestine change of the gluten itself, or, in other words, whether the oxygen com- 
 bines directly with the gluten, to give it a higher degree of oxidation, or whether it lays 
 hold of its hydrogen to form water. 
 
 " This oxidation of the gluten, from whichever cause, and the transformation of the 
 sugar into carbonic acid and alcohol, are two actions so correlated, that by an exclusion 
 of the one, the other is immediately stopped." 
 
 The superficial ferment (oberhefe in German) which covers the surface of the fer- 
 menting works is gluten oxidized in a state of putrefaction ; and the ferment of deposit 
 is the gluten oxidized in a state of tremacausie. 
 
 The surface yeast, or barm, excites in liqviids containing sugar and gluten the same 
 alteration which itself is undergoing, whereby the sugar and the gluten suffer a rapid 
 and tumultuous metamorphosis. We may form an exact idea of the different states of 
 these two kinds of yeast by comparing the superficial to vegetable matters putrefying 
 at the bottom of a marsh, and the bottom yeast to the rotting of wood in a state of 
 eremacausie, that is, of slow combustion. The peculiar condition of the elements of the 
 sediment ferment causes them to act upon the elements of the sugar in an extremely 
 slow manner, and excites the change into alcohol and carbonic acid, without that of the 
 dissolved gluten. 
 
 Sugar, which at ordinary temperatures has no tendency to combine with oxygen, 
 enters in the above predicament into fermentation ; but the action is rendered much 
 slower by the low temperature, while the affinity of the dissolved gluten for the oxygen 
 of the air is aided by the contact of the sediment. The superficial yeast may be 
 removed without stopping the fermentation, but the under yeast cannot be removed 
 without arresting all the phenomena of disoxidation of the second period. These would 
 immediately cease ; and if the temperature were now raised, they would be succeeded 
 by the phenomena of the first period. The deposit does not. excite the phenomena of 
 tumultuous fermentation, for which reason it is totally unfit for panification (bread- 
 baking), while the superficial yeast alone is suitable to this purpose. 
 
 If to wort at a temperature of from 46i° to 50° F. the top yeast be added, a quiet 
 slow fermentation is produced, but one accompanied with a rising up of the mass, while 
 yeast collects both at the surface and bottom of the backs. If this deposit be removed 
 to make use of it in other operations, it acquires by little and little the characters of the 
 unterhefe, and becomes incapable of exciting the phenomena of the first fermenting 
 period, causing only, at 59° F., those of the second ; namely, sedimentary fermentation. 
 It must be carefully observed that the right unterhefe is not the precipitate which falls 
 to the bottom of backs in the ordinary fermentation of beer, but is a matter entirely 
 different. Peculiar pains must be taken to get it genuine, and in a proper condition at 
 the commencement. Hence the brewers of Hessia and Prussia, who wished to make 
 Bavarian beer, found it more to their interest to send for the article to Wurtzburg, or 
 Bamberg, in Bavaria, than to prepare it themselves. When once the due primary 
 fermentation has been established and well regulated in a brewery, abundance of the 
 true unterhefe may be obtained for all future operations. 
 
BEER, BAVARIAN. 
 
 15 
 
 In a wort made to ferment at a low temperature with deposit only, the presence of 
 the unterhefe is the first condition essential to the metamorphosis of the saccharum, 
 but it is not competent to bring about the oxidation of the gluten dissolved in the 
 wort, and its transformation into an insoluble state. This change must be accom- 
 plished at the cost of the atmospherical oxygen. 
 
 In the tendency of soluble gluten to absorb oxygen, and in the free access of the air, 
 all the conditions necessary for its eremacausis, or slow combustion, are to be found. 
 It is known that the presence of oxygen and soluble gluten are also the conditions of 
 acetification (vinegar making), but they are not the only ones ; for this process requires 
 a temperature of a certain elevation for the alcohol to experience this slow combustion. 
 Hence, by excluding that temperature, the combustion (oxidation) of alcohol is ob- 
 structed, while the gluten alone combines with the oxygen of the air. This property 
 does not belong to alcohol at a low temperature, so that during the oxidation in this 
 case of the gluten, the alcohol exists alongside of it, in the same condition as the gluten 
 alongside of sulphurous acid in the muted wines. In wines not impregnated with the 
 fumes of burning sulphur, the oxygen which would have combined at the same time 
 with the gluten and the alcohol does not seize either of them in wines which have been 
 subjected to mutism, but it unites itself to the sulphurous acid to convert it into the 
 sulphuric. The action called sedimentary fermentation is therefore merely a simulta- 
 neous metamorphosis of putrefaction and slow combustion ; the sugar and the unterhefe 
 putrefy, and the soluble gluten gets oxidized, not at the expense of the oxygen of the 
 water and the sugar, but of the oxygen of the air, and the gluten then falls in the in- 
 soluble state. The process of Appert for the preservation of provisions is founded 
 upon the same principle as the Bavarian process of fermentation ; in which all the pu- 
 trescible matters are separated by the intervention of the air at a temperature too low 
 for the alcohol to become oxidized. By removing them in this way, the tendency of 
 the beer to grow sour, or to suffer a further change, is prevented. Appert's method 
 consists in placing in presence of vegetables or meat which we wish to preserve the 
 oxygen at a high temperature, so as to produce slow combustion, but without putre- 
 faction or even fermentation. By removing the residuary oxygen after the combustion 
 is finished, all the causes of an ulterior change are removed. In the sedimentary fer- 
 mentation of beer, we remove the matter which experiences the combustion ; whereas, 
 on the contrary, in the method of Appert, we remove that which produces it. 
 
 It is uncertain whether the dissolved gluten, in being converted into insoluble yeast 
 by the action of the oxygen, combines directly with the oxygen ; that is to say, whether 
 the yeast differs from the soluble gluten merely by having absorbed an additional quan- 
 tity of oxygen. This question is in fact very difficult to solve by analysis. If the gluten 
 be regarded as a hydrogenated combination, it is obvious that in the fermentation of 
 wine-must, and malt- wort, the hydrogen will be carried off by the oxygen, and the 
 action will then be the same as the transformation of alcohol into aldehyde. When the 
 contact of the atmosphere is excluded, this oxygen cannot evidently be derived from the 
 elements of the air, or from those of the water ; for it cannot be supposed that oxygen 
 will take hydrogen from the water, in order to re-compose water with the hydrogen of 
 the gluten. The elements of the saccharum must therefore furnish this oxygen ; or in 
 the course of the formation of the yeast, a portion of the sugar will be decomposed ; but 
 this decomposition is not of the same kind as that which results from the immediate 
 metamorphosis of the sugar into carbonic acid and alcohol ; hence a certain portion of 
 the sugar will afford neither alcohol nor carbonic acid, but it will yield less oxygenated 
 products from its elements. These products occasion the great difference in the qua- 
 lities of fermented liquors, and particularly in their alcoholic strength. In the ordinary 
 fermentation of grape juice and worts, these liquids do not furnish a quantity of alcohol 
 equivalent to the sugar which they contain, because a certain portion of the sugar serves 
 for the oxidation of the gluten, and is not transformed like the rest. But whenever the 
 liquor has arrived at the second period, the product in alcohol ought to be equivalent to 
 the quantity of sugar present, as happens in all fermentations which are not accom- 
 panied with a formation, but a disappearance of the yeast. It is well ascertained that 
 worts furnish in the Bavarian breweries 10 or 20 per cent, more alcohol than they do 
 by the ordinary process of fermentation. It is also a well-established fact that in the 
 manufacture of spirits from potatoes, where no yeast is produced, or merely a quantity 
 corresponding to the proportion of barley malt added to the potato- wort, a quantity of 
 alcohol may be produced, as also of carbonic acid, corresponding exactly to the 
 quantity of carbon in the fecula employed. But, on the contrary, in the fermentation 
 of beet-root juice, it is hardly possible to determine precisely, from the quantity of 
 carbonic acid evolved, the quantity of sugar contained in the beets, for there is always 
 less carbonic acid than the juice of the fresh root would furnish. In equal volumes, 
 the beer made by the unterhefe process contains more alcohol, and is therefore more 
 heady than that formed by the ordinary process. 
 
16 
 
 BEER, BAVARIAN. 
 
 The temperature at which fermentation is carried on has a very marked influence 
 upon the quantity of alcohol produced. It is known that the juice of beets set to 
 ferment between 86° and 95 Fahr. does not yield alcohol, and its sugar is replaced by 
 a less oxygenated substance, mannite, and lactic acid, resulting from the mucilage. 
 In proportion as the temperature is lowered the mannite fermentation diminishes. 
 As to azotized juices, however, it is hardly possible to define the conditions under 
 which the transformation of the sugar will take place, without being accompanied with 
 another decomposition which modifies its products. The fermentation of beer by 
 deposit demonstrates that by the simultaneous action of the oxygen of the air and a 
 low temperature, the metamorphosis of sugar is effected in a complete manner ; for 
 the vessels in which the operation is carried on are so disposed that the oxygen of the 
 air may act upon a surface great enough to transform all the gluten into insoluble 
 yeast, and thus to present to the sugar a matter constantly undergoing decomposition. 
 The oxidizement of the dissolved gluten goes on, but that of the alcohol requires a 
 higher temperature ; whence it cannot suffer eremacausis, that is, acetification, or con- 
 version into vinegar. 
 
 At the beginning of the fermentation of must and wort, the quantity of matter 
 undergoing change is obviously the largest. All the phenomena which accompany it, 
 the disengagement of gas and the rise of temperature, are most active at this period, 
 and in proportion as the decomposition advances, the external signs of it become less 
 perceptible, without, however, disappearing completely before the transformation has 
 reached its limit. The slow and continuous decomposition which succeeds to the 
 rapid and violent disengagement of gases is denominated the after or complementary 
 fermentation. For wine and beer it lasts till all the sugar has disappeared, so that the 
 specific gravity of the liquors progressively diminishes during several months. This 
 slow fermentation is in most cases a truly depositary fermentation ; for by the pro- 
 gressive decomposition of the lees, the sugar still in solution gets completely trans- 
 formed ; but when the air is excluded, that decomposition does not occasion the 
 complete separation of the azotized matters in an insoluble shape. 
 
 In several states of the German confederation, the favourable influence of a rational 
 process of fermentation upon the quality of the beers has been fully recognised. In 
 the Grand Duchy of He4se considerable premiums were proposed for the brewing of 
 beer according to the process pursued in Bavaria, which were decreed to those brewers 
 who were able to prove that their product (neither strong nor highly hopped) had kept 
 six months in the casks without becoming at all sour. When the first trials were being 
 made several thousand barrels were spoiled, till eventually experience led to the dis- 
 covery of the true practical conditions which theory had foreseen and prescribed. 
 
 Neither the richness in alcohol, nor in hops, nor both combined, can hinder ordinary 
 beer from getting tart. In England, says Liebig, an immense capital is sacrificed 
 to preserve the better sorts of ale and porter from souring, by leaving them for several 
 years in enormous tuns quite full, and very well closed, while their tops are covered 
 with sand. This treatment is identical with that applied to wines to make them 
 deposit the wine-stone. A slight transpiration of air goes on in this case through 
 the pores of the wood ; but the quantity of azotized matter contained in the beer is so 
 great, relatively to the proportion of oxygen admitted, that this element cannot act 
 upon the alcohol. And yet the beer thus managed will not keep sweet more than 
 two months in smaller casks to which air has access. The grand secret of the Munich 
 brewers is to conduct the fermentation of the wort at too low a temperature to permit 
 of the acetification of the alcohol, and to cause all the azotized matters to be com- 
 pletely separated by the intervention of the oxygen of the air, and not by the sacrifice 
 of the sugar. It is only in March and October that the good store beer is begun to 
 be made in Bavaria. 
 
 In our ordinary breweries, the copious disengagement of carbonic acid from the 
 frothy top of the fermenting tuns and gyles prevents the contact of oxygen from the 
 worts ; so that, as the gluten cannot be oxidized by the air, it attracts oxygen from 
 the sugar, and thus gives rise to several adventitious hydrogenated products, just as the 
 fetid oil is generated in the rapid fermentation of spirit wash by the distillers. In this 
 case no inconsiderable portion of the gluten remains undecomposed in the beer, which, 
 by its extreme proneness to corruption, afterwards attracts oxygen greedily from the 
 air, and, at temperatures above 52°, imparts this contact action to the alcohol, and, by 
 a species of infection, changes it into vinegar. Indeed, in most of the rapid fermentations 
 a portion of vinegar is formed, which itself serves as an acetous ferment to the rest of the 
 alcohol : whereas the result of the bottom fermentation is a beer free from vinegar, and 
 certainly hardly a trace of gluten ; so that it does not possess the conditions requisite 
 to intestine change or deterioration. This perfection is, however, in my opinion, rarely 
 attained. In my several journeys into Germany I have met with much spurious or 
 ill-made Bavarian beer. The best contains, when brought to England; a little acid, 
 
BEER, BAVARIAN. 
 
 17 
 
 but no perceptible gluten on the addition of ammonia in excess. Most of our beers, 
 ales, &c, deposit more or less gluten when thus treated. 
 
 The following Table exhibits the results of the chemical examination of the under- 
 mentioned kinds of beer : — 
 
 
 Quantity in 100 parts by weight. 
 
 Analyst. 
 
 Name of the Beer. 
 
 Water. 
 
 Malt extr. 
 
 Alcohol. 
 
 Carb. acid. 
 
 Augustine double-beer — • ~( 
 Munich - - J 
 
 Salvator beer — do. 
 
 Bock-beer from the Royal"! 
 brewery — do. - f 
 
 Schenk (pot) beer, from a BaO 
 varian country brewery; a I 
 kind of small beer - J 
 
 Bock-beer of Brunswick, of \ 
 the Bavarian kind - J 
 
 Lager (store) beer, of Bruns- | 
 wick, of the Bavarian kind j 
 
 Brunswick sweet small beer 
 
 Brunswick mum 
 
 88-36 
 
 87- 62 
 
 88- 61 
 
 92-94 
 
 88-50 
 
 91-0 
 
 84-70 
 59-2 
 
 8-0 
 8-0 
 7-2 
 
 4- 0 
 
 6-50 
 
 5- 4 
 
 140 
 39-0 
 
 3 6 
 4-2 
 
 4- 0 
 
 2- 9 
 
 5- 0 
 
 3- 50 
 
 1 30 
 1 80 
 
 0-14 
 0-18 
 016 
 
 0-16 
 O'l 
 
 Kaiser. 
 Do. 
 Do. 
 
 Do. 
 
 Balhovn. 
 
 Otto. 
 
 Do. 
 Kaiser. 
 
 Malting in Munich. — The barley is steeped till the acrospire, embryo, or seed-germ, 
 seems to be quickened; a circumstance denoted by a swelling at the end of that ear 
 which was attached to the foot-stalk, as also when, on pressing a pile between two 
 fingers against the thumb nail, a slight projection of the embryo is perceptible. As 
 long, however, as the seed-germ sticks too firm to the husk, it has not been steeped 
 enough for exposure on the underground malt floor. Nor can deficient steeping be 
 safely made up for afterwards by sprinkling the malt-couch with a watering-can, which 
 is apt to render the malting irregular. The steep -water should be changed repeatedly, 
 according to the degree of foulness and hardness of the barley ; first, six hours after 
 immersion, having previously stirred the whole mass several times ; afterwards, in 
 winter, every twenty-four hours, but in summer every twelve hours. It loses none of 
 its substance in this way, whatever vulgar prejudice may think to the contrary. After 
 letting off the last water from the stone cistern, the Bavarians leave the barley to drain 
 in it during four or six hours. It is now taken out, and laid on the couch floor, in a 
 square heap, eight or ten inches high, and it is turned over, morning and evening, with 
 dexterity, so as to throw the middle portion upon the top and bottom of the new-made 
 couch. When the acrospire has become as long as the grain itself, the malt is carried 
 to the withering (welkboden) or drying floor, in the open air, where it is exposed (in 
 dry weather) during from eight to fourteen days, being daily turned over three times 
 with a winnowing shovel. It is next dried on a well-constructed cylinder or flue- 
 heated malt-kiln, at a gentle clear heat, without being browned in the slightest degree, 
 while it turns friable into a fine white meal. Smoked malt is entirely rejected by the 
 best Bavarian brewers. Their malt is dried on a series of wove- wire horizontal shelves, 
 placed over each other ; up through whose interstices or perforations streams of air, 
 heated to only 122° Fahr., rise, from the surfaces of rows of hot sheet-iron pipe-flues, 
 arranged a little way below the shelves. Into these pipes the smoke and burned air of 
 a little furnace on the ground are admitted. The whole is enclosed in a vaulted chamber, 
 from whose top a large wooden pipe issues, for conveying away the steam from the 
 drying malt. Each charge of malt may be completely dried on this kiln in the space 
 of from eighteen to twenty-four hours, by a gentle uniform heat, which does not injure 
 the diastase, or discolour the farina. * 
 
 The malt for store-beer should be kept three months at least before using it, and 
 be freed by rubbing and sifting from the acrospires before being sent to the mill, 
 where it should be crushed pretty fine. The barley employed is the best distichon 
 or common kind, styled hordenm vulgare. 
 
 The hops are of the best and freshest growth of Bavaria, called the fine spalter, or 
 saatser Bohemian townhops, and are twice as dear as the best ordinary hops of the rest 
 of Germany. They are in such esteem as to be exported even into France. 
 
 The Bavarians are so much attached to the beer beverage, which they have enjoyed 
 from their remotest ancestry, that they regard the use of distilled spirits, even in 
 moderation, as so immoral a practice, as to disqualify dram-drinkers for decent society. 
 
 * I have a set of designs of the Bavarian kiln, but I believe the above description will make its con- 
 struction sufficiently intelligible. 
 
 D 
 
18 
 
 BEER, BAVARIAN. 
 
 Their government has taken great pains to improve this national beverage, by en- 
 couraging the growth of the best qualities of hops and barley. The vaults in which 
 the beer is fermented, ripened, and kept are all underground, and mostly in stony ex- 
 cavations, called felsenkeller or rock-cellars. The beer is divided into two sorts, called 
 summer and winter. The latter is light, and, being intended for immediate retail in 
 tankards, is termed schanhbier. The other, or the lagerbier, very sensibly increases in 
 vinous strength in proportion as it decreases in sweetness, by the judicious manage- 
 ment of the nachgdhrung, or fermentation in the casks. In several parts of Germany a 
 keeping quality is communicated to beers by burning sulphur in the casks before 
 filling them, or by the introduction of sulphite of lime. But the flavour thus im- 
 parted is disliked in Munich, Bayreuth, Regensburg, Niirnberg, Hof, and the other 
 chief towns of Bavaria ; instead of which a preservative virtue is sought for in an 
 aromatic mineral or Tyrol pitch, with which the inside of the casks are carefully coated, 
 and in which the ripe beer is kept and exported. In December and January, after the 
 casks are charged with the summer or store-beer, the double doors of the cellars are 
 closed, and lumps of ice are piled up against them, to prevent all access of warm air. 
 The cellar is not opened till next August, in order to take out the beer for consump- 
 tion. In these circumstances the beer becomes transparent like champagne wine ; 
 and, since but little carbonic acid gas has been disengaged, little or none of the 
 additionally generated alcohol is lost by evaporation. 
 
 The winter or schank (pot) beer is brewed in the months of October, November, 
 March, and April; but the summer or store-beer in December, January, and Feb- 
 ruary, or the period of the coldest weather. For the former beer, the hopped worts 
 are cooled down only to from 51° to 55°, but for the latter to from 41° to 42^° Fahr. 
 The winter beer is also a little weaker than the summer beer, being intended to be 
 sooner consumed; since four bushels* (Berlin measure) of fine, dry, sifted malt, of 
 large heavy hordeum vulgare distichon, affords seven eimers of winter beer, but not more 
 than from five and a half to six of summer beer.f At the second infusion of the worts, 
 small beer is obtained to the amount of twenty quarts from the above quantity of malt. 
 For the above quantity of winter beer, six pounds of middling hops are reckoned 
 sufficient ; but for the summer beer, from seven to eight pounds of the finest hops. 
 The winter beer may be sent out to the publicans in barrels five days after the fer- 
 mentation has been completed in the tuns, and, though not quite clear, it will become 
 so in the course of six days : yet they generally do not serve it out in pots for two or 
 three weeks. But the summer beer must be perfectly bright and still before it is 
 racked off into casks for sale. 
 
 Statement of the Products of a Brewing of Bavarian Beer. — The quantity brewed is 
 41 Munich eimers (64 maass) = 85^ Berlin quarts ; and 60 Berlin quarts = 1 eimer ; 
 or 24 Munich barrels (of 100 Berlin quarts each); 1 Munich eimer =15 gallons 
 Imperial. The beer contains from 50 to 60 parts, by weight, of drysaccharum in 1000 
 parts. 
 
 Expenditure. 
 
 Thaler. Slbg. 
 
 24» Berlin bushels of white kiln-dried barley, rather finely crushed, 
 
 weighing from 12 to 13 cwts. 
 36 pounds of new fine spalter (parted) hops at 46 thalers the cwt. 
 i pound of Carageen moss, for clarifying 
 1 quart of yeast. 
 1 quart of Tyrol pitch - 
 
 Mash — tax (in Bavaria and Prussia) upon 12 cwt. malt, at the 
 
 rate of 20 silbergroschen = 2s., the cwt. - 
 Cost of crushing - - - - 
 
 Fuel - 
 
 Wages of labour, in the brewhouse and vault 
 
 Do. do. for cooper in pitching the casks 
 Sundry small expenses - 
 
 Or 117. 85. 
 1 thaler = 30 silbergroschen = 3 shillings. 
 
 Deduct for the grains of 12 cwt. of malt, at 10 silbergroschen, or 1 
 per cwt. = 4 thalers, and for the value in yeast produced = 
 thalers more - - - - 
 
 Total neat expenditure = 10Z. 10s. 
 
 - 24 
 
 0 
 
 - 16 
 
 17 
 
 - 0 
 
 3 
 
 - 11 
 
 0 
 
 8 
 
 0 
 
 1 
 
 0 
 
 - 4 
 
 0 
 
 6 
 
 0 
 
 3 
 
 0 
 
 2 
 
 10 
 
 76 
 
 0 
 
 s. 
 2 
 
 
 6 
 
 0 
 
 • 70 
 
 0 
 
 * An English quarter of cram is equal to 5 bushels (sckeffi'l) and nearly one-third Prussian measure, 
 t 1 Eimer Prussian = 15^ English Imperial gallons ; one Munich schejffel is equal to four Berlin schcffcls , 
 1 Lib. Munich = 1-235 Eng. lbs. Avoird. ; 1 Lib. Berlin = L031 lbs. Avoird. 
 
BEER, BAVARIAN. 
 
 19 
 
 This cost for 42 eimers (1 eimer = 14* galls. Imp.) = 619| gallons =17-2 London 
 porter barrels, amounts to 4±d. per gallon, or 12s. 2d. per barrel. By the above 
 reckoning, a good profit accrues to the brewer, after allowing a liberal sum for the 
 rent of premises, interest of capital, &c. 
 
 He has less profit from the summer beer. For a brewing of 33 eimers = 505 gallons 
 Imp., containing from 60 to €5 pounds of saccharum in 1000 pounds of the beer, by 
 Hermstaedt's saccharometer. 
 
 Expenditure. 
 
 Thaler. 
 
 Slbg. 
 
 24 Berlin scheffels of white kiln-dried barley malt, weighing from 
 
 
 
 12 to 13 centners* - - - - - 
 
 24 
 
 0 
 
 48 Berlin pounds of fresh Bavarian fine hops, at 46 thaler per centner 
 
 20 
 
 0 
 
 i pound of Carageen moss 
 
 0 
 
 3 
 
 ] quart setting yeast (unterhefe). 
 
 11 
 
 
 1 centner pitch - 
 
 0 
 
 Malt tax on 12 centners - 
 
 8 
 
 0 
 
 Crushing the malt - 
 
 1 
 
 0 
 
 Fuel - 
 
 4 
 
 0 
 
 Wages, 6 thalers ; coopers' do., 3 thalers ; and sundries, 3 th. 27 sq. 
 
 12 
 
 27 
 
 
 81 
 
 0 
 
 Deduct for grains 4 thalers, and yeast 2 thalers 
 
 6 
 
 0 
 
 Neat cost ------ 
 
 75 
 
 0 
 
 This cost of 11/. 5s. for 505 gallons amounts to fully 5\d. per gallon, and 16s. 6d. 
 per barrel. 
 
 The cost at Munich is 2± thalers the eimer, and 4 thalers the barrel. The eimer of 
 the summer beer, or lagerbier, is sold for 4 thalers. The publicans there, as in London, 
 are known to add more or less water to their beer before retailing it. 
 
 The yeast (unterhefe) is carefully freed by a scraper from the portions of light top 
 yeast that may have fallen to the bottom ; the true unterhefe is then carefully sliced off 
 from the slimy sediment on the wood. 
 
 In Munich the malt is moistened slightly 1 2 or 16 hours before crushing it, with from 
 2 to 3 maasj- of water for every bushel ; the malt being well dried, and several months 
 old. The mash -tun into which the malt is immediately conveyed is, in middle-sized 
 breweries, a round oaken tub, about 41 feet deep, 10 feet in diameter at bottom and 
 9 at top, outside measure, containing about 6000 Berlin quarts. Into this tun cold 
 water is admitted late in the evening, to the amount of 25 quarts for each schrffd, or 
 600 quarts for the 24 scheffels of the ground malt, which are then shot in and stirred 
 about and worked well about with the oars and rakes, till a uniform pasty is formed 
 without lumps. It is left thus for three or four hours ; 3000 quarts of water bejng 
 put into the copper, and made to boil; and 1800 quarts are gradually run down into 
 the mash-tun, and worked about in it, producing a mean temperature of 142-5° Fahr. 
 After an hour's interval, during which the copper has been kept full, 1800 additional 
 quarts of water are run into the tun, with suitable mashing. The copper being now 
 emptied of water, the mash-mixture from the tun is transferred into it, and brought 
 quickly to the boiling point, with careful stirring to prevent its setting on the bottom 
 and getting burned, and it is kept at that temperature for half an hour. When the mash 
 rises by the ebullition, it needs no more stirring. This process is called, in Bavaria, 
 boiling the thick mash, dickmaisch kochen. The mash is next returned to the tun, and 
 well worked about in it. A few barrels of a thin mash-wort are kept ready to be put 
 into the copper the moment it is emptied of the thick mash. After a quarter of an 
 hour's repose the portion of liquid filtered through the sieve part of the bottom of 
 the tun into the wort-cistern is put into the copper, thrown back boiling hot into the 
 mash in the tun, which is once more worked thoroughly. 
 
 The copper is next cleared out, filled up with water, which is made to boil for the 
 after or small beer brewing. After two hours settling in the open tun, the worts are 
 drawn off clear. 
 
 Into the copper, filled up one foot high with the wort, the hops are introduced, and 
 the mixture is made to boil during a quarter of an hour. This is called roasting the 
 hops. The rest of the wort is now put into the copper, and boiled along with the hops 
 during at least an hour or an hour and a half. The mixture is then laded out through 
 the hop-filter into the cooling cistern, where it stands three or four inches deep, and is 
 exposed upon an extensive surface to natural or artificial currents of cold air, so as to 
 
 * 1 Centner = 110 Prussian pounds = 113 44 lbs. Avoird. 
 t A Bavarian maas — If quarts English measure. 
 D 2 
 
20 
 
 BEER, BAVARIAN. 
 
 be quickly cooled. For every 20 barrels of lagerbier, there are allowed 10 of small 
 beer ; so that 30 barrels of wort are made in all. 
 
 For the winter or pot-beer the worts are brought down to about 59° Fahr. in the 
 cooler, and the beer is to be transferred into the fermenting tuns at from 54*5° to 59° 
 Fahr. ; for the summer or lagerbier, the worts must be brought down in the cooler to 
 from 43° to 45^°, and put into the fermenting tuns at to from 41° to 43° Fahr. 
 
 A few hours beforehand, while the wort is still at the temperature of 63i° Fahr., a 
 quantity of lobb must be made, called vorstdlen { fore-setting) in German, by mixing the 
 proportion of unterhefe (yeast) intended for the whole brewing with a barrel or a 
 barrel and a half of the worts, in a small tub called the gahr-tiene, stirring them well 
 together, so that they may immediately run into fermentation. This lobb is in this 
 state to be added to the worts. The lobb is knov/n to be ready when it is covered with 
 a white froth from one quarter to one half an inch thick ; during which it must be well 
 covered up. The large fermenting tun must in like manner be kept covered, even in 
 the vault. The colder the worts, the more yeast must be used. For the above 
 quantity, at 
 
 From 57° to 59° Fahr., 6 maas of unterhefe. 
 53° to 55° 8 • — 
 
 48° to 50° 10 — 
 
 41° to 33° 12 — 
 
 Some recommend that wort for this kind of fermentation (the imtergahrung) should be 
 set with the yeast at from 48° to 57° ; but the general practice at Munich is to set the 
 summer lager beer at from 41° to 43° F. 
 
 By following the preceding directions, the wort in the tun should, in the course of 
 from twelve to twenty-four hours, exhibit a white froth round the rim, and even a slight 
 whiteness in the middle. After another twelve to twenty-four hours, the froth should 
 appear in curls ; and, in a third like period, these curls should be changed into a still 
 higher frothy brownish mass. In from twenty-four to forty-eight hours more, the barm 
 should have fallen down in portions through the beer, so as to allow it to be seen in certain 
 points. In this case it may be turned over into the smaller ripening tuns in the course 
 of other five or six days. But when the worts have been set to ferment at from 41° to 
 43° Fahr., they require from eight to nine days. The beer is transferred, after being 
 freed from the top yeast by a skimmer, by means of the stopcock near the bottom of 
 the large tun. It is either first run into an intermediate vessel, in order that the top 
 and bottom portions may be well mixed, or into each of the lager casks, in a numbered 
 series, like quantities of the top and bottom portions are introduced. In the ripening 
 cellars the temperature cannot be too low. The best keeping beer can never be 
 brewed unless the temperature of the worts at setting, and of course the fermenting 
 vault, be as low as 50° F. In Bavaria, where this manufacture is carried on under 
 government inspectors, a brewing period is prescribed by law, which is, for the under 
 fermenting lager beer, from Michaelmas (29th September) to St. George (23d April). 
 From the latter to the former period the ordinary top-barm beer alone is to be made. 
 The ripening casks must not be quite full, and they are to be closed merely with a 
 loose bung, in order to allow of the working over of the ferment. But should the fer- 
 mentation appear too languid, after six or eight days, a little briskly fermenting lager 
 beer may be introduced. The store lager beer tuns are not to be quite filled, so as to 
 prevent all the yeasty particles from being discharged in the ripening fermentation ; 
 but the pot lager beer tuns must be made quite full, as this beverage is intended for 
 speedy sale within a few weeks of its being made. 
 
 As soon as the summer-beer vaults are charged with their ripening casks, and with 
 ice-cold air, they are closed air-tight with triple doors, having small intervals between, 
 so that one may be entered and shut again, before the next is opened. These vaults 
 are sometimes made in ranges radiating from a centre, and at others in rooms set off 
 at right angles to a main gallery ; so that in either case, when the external opening is 
 well secured, with triple air-tight doors, it may be entered at any time, in order to 
 inspect the interior, without the admission of warm air to the beer-barrels. The 
 wooden bungs for loosely stopping them must be coated with the proper pitch, to 
 prevent the possibility of their imparting any acetous ferment. In the Beer Brewer * 
 of A. F. Zimmermann, teacher of theoretical and practical brewing, who has devoted 
 thirty-five years to this business, it is stated, that a ripened tun of lager or store-beer 
 must be racked off all at once, for when it is left half full it becomes flat (schaal) ; and 
 that the tun of pot lager beer must, if possible, be all drunk off in the same day it is 
 tapped ; because on the following day the beer gets an unpleasant taste, even when 
 the bung has not been taken out, but only a small hole has been made, which is 
 opened only at the time of drawing the beer, and is immediately closed again with a 
 
 * Der Eier-Brauer, als Meister in seinem fache, &-c, illustrated with many plates, Berlin, 1 84*2. 
 
BEER, BAVARIAN. 
 
 2] 
 
 spigot. He ascribes this change to the loss of the carbonic acid gas, with which the 
 beer has got strongly impregnated during the latter period of its ripening, while 
 being kept in tightly-bunged casks. The residuums in these casks are, however, 
 bottled up in Bavaria, whereby the beer, after some time, recovers its brisk and 
 pungent taste. But the beer-topers in Bavaria, who are professedly very numerous, 
 indulge so delicate and fastidious a palate, that when assembled in their favourite pot- 
 house, they wait impatiently for the tapping of a fresh cask, and cease for a Avhile to 
 tipple whenever it is half empty, puffing the time away with their pipes till another 
 fresh tap be made. In the well-frequented beer-shops of Munich a common-sized 
 cask of lager beer is thus drunk off in an hour. A reputation for superior brewing is 
 there the readiest road to fortune. 
 
 Bock Beer of Bavaria. — This is a favourite double strong beverage, of the best lager 
 description, which is so named from causing its consumers to prance and tumble about 
 like a buck or a goat; — for the German word bock has both these meanings. It is 
 merely a beer having a specific gravity one-third greater, and is therefore made with 
 a third greater proportion of malt, but with the same proportion of hops, and flavoured 
 with a few coriander seeds. It has a somewhat darker colour than the general lager 
 beer, occasionally brownish, taste less bitter on account of the predominating malt, 
 and somewhat aromatic. It is an eminently intoxicating beverage. It is brewed in 
 December and January, and takes a long time to ferment and ripen ; but still it 
 contains too large a quantity of unchanged saccharum and dextrine for its hops, so that 
 it tastes too luscious for habitual topers, and is drunk only from the beginning of May 
 till the end of July, when the fashion and appetite for it are over for the year. 
 
 Statement of a Brewing of Bavarian Bock Beer. 
 
 For 41 Bavarian eimers of 64 maass each (about 15 gallons Imperial) per cimer, or 
 615 gallons, nearly 17 barrels English in all : — 
 
 Expenditure. 
 
 Thaler. Slbg. 
 
 32 Berlin scheffels of the best pale malt freed from its acrospires, 
 
 weighing \1\ centners, at 1 thaler per centner - 32 0 
 
 48 lbs. (Berlin) of "the best Bavarian hops - - 20 0 
 
 i lb. Carageen moss for clarifying - - - 0 3 
 
 1 lb. Coriander seeds - - - -• - Oli 
 1 Quart setting yeast. 
 
 1 Centner Tyrolese pitch - - - - 110 
 
 Malt-tax — - - - - - 11 20 
 
 Malt-crushing, fuel, wages, coopering, &c. - - 16 5\ 
 
 Thalers of 3s. each - 910 
 
 Deduct for the value of grains and yeast - 7 0 
 
 Thalers of neat cost - 84 0 
 
 This statement makes the euner of the Bavarian bock-beer amount to about 2 
 thalers, or 6 shillings ; being at the rate of nearly 5 pence per gallon ; though without 
 counting rent, interest of capital, or profit. It is, in fact, a malt or barley sweet wine 
 or liqueur ; but a very cheap one, as we see by this computation. 
 
 The chief difference in the process for making bock-beer lies in the mash-worts, 
 and in the hops being boiled a shorter time, to preserve more of the aroma, and acquire 
 less of the bitterness of the hop. The coriander seeds are coarsely bruised, and added 
 along with the hops and Carageen moss, to the boiling mash-worts, about twenty 
 or thirty minutes before they are laded or drawn off, into the mash-tun. Sometimes 
 the hops are boiled apart in a little clear wort, as formerly described. The bock-beer 
 is retailed in Munich at 3 silver groschen, about S\d. the seidel, or pot, which is one 
 English pint. The 25 gallon cask (tonne) is sold at 10 thalers, or 30 shillings. The 
 publicans, therefore, have a very remunerating profit per pot, even supposing that they 
 do not reduce the beer with water like our London craftsmen. 
 
 Zimmermann assumes the merit of having introduced Carageen moss as a clarifier 
 into the beer manufacture. I do not know whether it may not have been used in this 
 country for the same purpose, or in Ireland, where this fucus ( Chondra crispa) grows 
 abundantly. He says that 1 ounce of it is sufficient for 25 gallons of beer; and that 
 it operates, not only in the act of boiling with the hops, but in that of cooling, as also 
 in the squares and backs before the fermentation has begun. Whenever this change, 
 however, takes place, the commixture throws up the gluten and moss to the surfr.ee of 
 the liquid in a black scum, which is to be skimmed off, so that the proper yeast may 
 
22 
 
 BEER, BAVARIAN. 
 
 not be soiled with it. It occasions the separation of much of the vegetable slime, or 
 mucilage, called by the German brewers pech (pitch). 
 
 On the Clarifying or Clearing of Beers. — Clarifiers act either chemically, — by being 
 soluble in the beer, and by forming an insoluble compound with the vegetable gluten, 
 and other viscid vegetable extracts ; gelatine and albumen, under one shape or other, 
 have been most used ; the former for beer, the latter, as white of egg, for wine, — 
 or mechanically, by being diffused in fine particles through the turbid liquor, and, in 
 their precipitation, carrying down with them the floating vegetable matters. To this 
 class belong sand, bone-black (in some measure, but not entirely), and other such 
 articles. The latter means are very imperfect, and can take down only sueh matters 
 as exist already in an insoluble state; of the former class, milk, blood, glue, calf's-foot 
 jelly, hartshorn shavings, and isinglass, have been chiefly recommended. Calves'-feet 
 jelly is much used in many parts of Germany, where veal forms so common a kind of 
 butcher-meat ; but in summer it is apt to acquire a putrid taint, and to impart the 
 same to the beer. In these islands, isinglass swollen and partly dissolved in vinegar, 
 or sour beer, is almost the sole clarifier, called finings, employed. It is costly, when 
 the best article is used; but an inferior kind of isinglass is imported for the brewers. 
 The solvent or medium through or with which it is administered is eminently inju- 
 dicious, as it never fails to infect the beer with an acetous ferment. In Germany 
 their tart wine has been used hitherto for dissolving the isinglass ; and this has also the 
 same bad property. Mr. Zimmermann professes to have discovered an unexception- 
 able solvent in tartaric acid, one pound of which dissolved in 24 quarts of water is 
 capable of dissolving two pounds of ordinary isinglass ; forming finings which may be 
 afterwards diluted with pure water at pleasure. Such isinglass imported from Peters- 
 burg into Berlin costs there only 3s. per lb. These finings are best added, as already 
 mentioned, to the worts prior to fermentation, as soon as they are let in to the setting- 
 back or tun, immediately after adding the yeast to it. They are best administered by 
 mixing them in a small tub with thrice their volume of wort, raising the mixture into a 
 froth with a whisk (tivig-besom, in German), and then stirring it into the worts. The 
 clarification becomes manifest in the course of a few hours, and when the fermentation 
 is completed, the beer will be as brilliant as can be wished ; the test of which with the 
 German topers is when they can read a newspaper while a tall glass beaker of beer is 
 placed between the paper and the candle. One quart of finings of the above strength 
 will be generally found adequate to the clearing of 100 gallons of well-brewed lager- 
 beer, though it will be surer to use double that proportion of finings. The Carageen 
 moss, as finings, is to be cut in fine shreds, thrown into the boiling thin wort, when 
 the flocks begin to separate, and before adding the hops ; after which the boiling is 
 continued for an hour and a half or two hours, as need be. The clarifying with this 
 kind of finings takes place in the cooler, so that a limpid wort may be drawn off into 
 the fermenting back. 
 
 Berlin White or Pale Beer {Weiss-bier). — This is the truly patriotic beverage of 
 Prussia Proper, and he is not deemed a friend to his Vaterland who does not swig it. 
 It is brewed from 1 part of barley malt and 5 parts of wheat malt, mingled, moistened, 
 and coarsely crushed between rollers. This mixture is worked up first with water at 
 95° Fahr., in the proportion of 30 quarts per scheffel of the malt, to which pasty 
 mixture 70 quarts of boiling water are forthwith added, and the whole is mashed in the 
 tun. After it has been left here a little to settle, a portion of the thin liquor is drawn 
 off by the tap, transferred to the copper, and then for each bushel of malt there is added 
 to it a decoction of half a pound of Altmark hops separately prepared. This hopped 
 wort, after half an hour's boiling, is turned back with the hops into the mash-tun, of 
 which the temperature should now be 162i° Fahr., but not more. In half an hour 
 the wort is to be drawn off from the grains, and pumped into the cooler. The grains 
 are afterwards mashed with from 40 to 50 quarts of boiling water per scheffel of malt, 
 and this infusion is drawn off and added to the former worts. The whole mixture 
 is set at 66° Fahr., with a due proportion of top yeast or ordinary barm, and very 
 moderately fermented. According to Zimmermann, a very competent judge, this his 
 native beer is very apt to turn sour, and therefore it must be very speedily consumed. 
 This proneness to acetification is the character of all wheat-malt beers. He recom- 
 mends, what he himself has made for many years, a substitution of potato-starch sugar 
 for this sort of malt, and as much tartaric acid as to give the degree of tartness peculiar 
 to the pale Berlin beer, even in its best state. This acid moreover prevents the beer 
 from running into the acetous fermentation. 
 
 Potato Beer. — The potatoes being well washed are to be rubbed down to a pulp by 
 such a grating cylinder machine as is represented in fig. 5., where a is the hopper for 
 receiving the roots (whether potato or beet, as in the French sugar factories) ; b is the 
 crushing and grinding drum ; c, the handle for turning the spur-wheel d, which drives 
 the pinion e, and the fly-wheel/; g, h, is the frame. The dotted lines above e, are the 
 
BEER, BAVARIAN. 
 
 23 
 
 cullender through which the pulp passes. Fig. 6. is the stopcock used in Bavaria for 
 bottling beer. For every scheffel of potatoes 80 quarts of water are to be put with 
 them into the copper, and made to boil. 
 
 Crushed malt, to the amount of 1 2 scheffels, is to be well worked about in the mash- 
 tun with 360 quarts, or 90 gallons (English), of cold water, to a thick pap, and then 
 840 additional quarts, or about 6 barrels (English), of cold water are to be successively 
 introduced with constant stirring, and left to stand an hour at rest. 
 
 The potatoes having been meanwhile boiled to a fine starch paste, the whole malt- 
 mash, thin and thick, is to be speedily laded into the copper, and the mixture in it is 
 to be well stirred for an hour, taking care to keep the temperature at from 144° to 
 156° Fahr. all the time, in order that the diastase of the malt may convert the starch 
 present in the two substances into sugar and dextrine. This transformation is made 
 manifest by the; white pasty liquid becoming transparent and thin. Whenever this 
 
24 
 
 BEER, BAVARIAN. 
 
 happens the fire is to be raised, to make the mash boil, and to keep it at this heat for 1 0 
 minutes. The fire is then withdrawn, the contents of the copper are to be transferred 
 into the mash, worked well there, and left to settle for half an hour ; during which 
 time the copper is to be washed out, and quietly charged once more with boiling water. 
 
 The clear wort is to be drawn off from the top of the tun, as usual, and boiled as 
 soon as possible with the due proportion of hops ; and the boiling water may be added 
 in any desired quantity to the drained mash, for the second mashing. Wort made in 
 this way is said to have no flavour whatever of the potato, and to clarify more easily 
 than malt- wort, from its containing a smaller proportion of gluten relatively to that of 
 saccharum. 
 
 A scheffel of good mealy potatoes affords from 26 to 27.j pounds of thick well-boiled 
 syrup, of the density of 36° Baume (see Areometer in the Dictionary); and 26 lbs. 
 of such syrup are equivalent to a scheffel of malt in saccharine strength. Zim- 
 mermann thinks beer so brewed from potatoes quite equal, at least, if not superior, to 
 pure malt beer, both in appearance and quality. 
 
 Porter and Brown Sto7it. — I offer the following statement of the process for brewing 
 genuine London porter, believing it to be more near that really practised than any 
 formula hitherto published. 
 
 For 180 barrels of brown stout, 'containing from 80 to 85 parts of malt extract in 
 1000 by weight: — 
 
 Components. — 530 bushels (English measure) of good barley malt. 
 
 10 do. of kiln-browned malt. 
 
 12 cwt. of Essentia-bina, Caramel, or sugar fused over a fire into 
 a dark brown or black syrupy mass. 
 1500 lbs. of hops, or about 3 pounds to each bushel of malt. 
 
 10 quarts of Calfini, a preparation made with the oil distilled from 
 the outer bark of the birch. 
 5 quarts of good porter yeast, 
 finings of isinglass dissolved in sour beer. 
 For the brewing process see Beer in the Dictionary. 
 
 The essentia-bina may be dissolved in hot worts in a separate copper, and mixed 
 with the rest by running it into the cooler, immediately after the boiled wort is 
 strained from the hops in the hop-back. The Calfini (a hocus-pocus term of the 
 brewers) is prepared as follows : — 
 
 Put one ounce of birch-bark oil into a bottle with 4 quarts of spirits of wine 60 per 
 cent, over proof ; cork the mouth of the bottle, and place it in a slightly wai*m position 
 till the oil be thoroughly combined with the alcohol, with the aid of occasional 
 shaking. This solution being cooled is to be filtered through paper, and kept for use. 
 The birch oil is an empyreumatic product made in large quantities in Russia and 
 Poland, for the purpose of giving flavour and conservative properties to the Russia 
 leather. It is sold for one shilling the quart. The dose of Calfini in porter is varied 
 according to the taste of the brewers and consumers. See Appendix. 
 
 In concluding this supplementary article, I take occasion to refer my readers to the 
 Practical Treatise on Brewing, by Mr. William Black, a gentleman experienced in the 
 business, who has the merit of discovering the evil influence of galvanic combi- 
 nations in the metallic parts of the fermenting backs and the beer tuns in our 
 breweries. This little work contains much useful information. I have pleasure also 
 in announcing that Messrs. Beamish and Crawford, the eminent porter brewers of 
 Cork, have taken measures to establish the manufacture of genuine Bavarian beer on 
 the best principles ; having, with this view, caused their intelligent head brewer, 
 Mr. Topp, to study the practical details of brewing in Munich. They have recently 
 produced excellent brown stout, equal, if not superior, to any in London, by means of 
 the Bavarian fermentation. It is nearly free from gluten, and will therefore prove light 
 and wholesome to weak stomachs. It needs no finings to clarify it. 
 
 Professor Leo of Munich has given the following analysis of two kinds of Munich 
 beer : — 
 
 Specific gravity 
 
 Bock-bier. 
 
 Heiliger Vater. 
 
 1-020 
 
 1-030 
 
 Alcohol 
 Extract 
 Carbonic acid 
 Water - 
 
 4-000 
 8-200 
 0-085 
 87-393 
 
 5-000 
 13-500 
 
 0-077 
 81-923 
 
 100-000 
 
 100-000 
 
BICARBONATE OF POTASH AND OF SODA. 25 
 
 Carl states the alcohol in the Bavarian beer of Bamberg at only 2-840 in 100 
 Extract, 6-349. 
 
 The following analyses of other German beers are also by Leo : — 
 
 
 Lichtenhain. 
 
 Upper 
 Weimar. 
 
 Ilmenau. 
 
 Jena. 
 
 Double Jena. 
 
 Alcohol 
 
 3-168 
 
 2-567 
 
 3-096 
 
 3-018 
 
 2-080 
 
 Albumen 
 
 0-048 
 
 0-020 
 
 0 079 
 
 0-045 
 
 0-028 
 
 Extract 
 
 4-485 
 
 7*316 
 
 7-072 
 
 6-144 
 
 7-153 
 
 Water 
 
 92 -299 
 
 90-097 
 
 89-753 
 
 90-793 
 
 90-739 
 
 
 100-000 
 
 100-000 
 
 100 000 
 
 100-000 
 
 100-000 
 
 Under the term extract, in these analyses, is meant a mixture of starch, sugar, dex- 
 trine, lactic acid, various salts, certain extractive and aromatic parts of the hop, gluten, 
 and fatty matter. 
 
 The following statement is from some of the published analyses of other beers : — 
 
 Alcohol. 
 
 English ale - - - - 8-5 in 100 
 
 Burton - - - - 6-2 
 
 Scotch - - - - 5-8 
 
 Common London ale - - - 5 -0 
 
 Brown stout - - .- - 5 "0 
 
 London porter - - - 4-0 
 
 To the above I add the following analyses of certain ales made lately by myself, as 
 follows : — 
 
 1 . After exposing a portion of the liquor in a wine glass till the bubbles of carbonic 
 acid were disengaged, I took the specific gravity in a globe with a capillary bored 
 stopper. 
 
 2. I then saturated 5000 grain measures of the ale with a test solution of pure car- 
 bonate of soda, to determine the quantity of acid present, after which I added an excess 
 of the alkali to precipitate the gluten ; which, however, being but small in amount, I 
 did not separate by a filter, dry, and weigh. 
 
 3. I subjected the supersaturated liquid to distillation by the heat of 230° F. in a 
 chlor-zinc bath till I drew off all its alcohol, of which I noted the quantity in water 
 grain measures, and the specific gravity. 
 
 4. I evaporated to dryness 500 water grain measures slowly in a porcelain capsule, 
 to determine the extract. 
 
 
 Bavarian. 
 
 Do. Bock. 
 
 Allsop's. 
 
 Bass's. 
 
 Specific gravity 
 
 1-004 
 
 1013 
 
 1-010 
 
 1-006 
 
 Alcohol 
 
 4-00 
 
 4-50 
 
 6-00 
 
 7-00 
 
 Extract 
 
 4-50 
 
 6-40 
 
 5-00 
 
 4-80 
 
 Acetic acid 
 
 0-20 
 
 0-20 
 
 0-20 
 
 0-18 
 
 Water - 
 
 91-30 
 
 88-90 
 
 88-80 
 
 88-02 
 
 
 100-00 
 
 100-00 
 
 100*00 
 
 100-00 
 
 The Bavarian beers had been recently imported from Germany in casks lined with 
 pitch. The two samples of English ale are those made chiefly for the Indian market, 
 but, being highly hopped, and comparatively clean, as the brewers say, have been 
 recommended as a tonic beverage by the faculty. Hodgson's bitter beer was the 
 original of this quality. 
 
 The above Bavarian beers afford no precipitate of gluten with carbonate of potash ; 
 the two English ales become mottled thereby, and yield a small portion of gluten, 
 which had been held in solution by the acid, which is here estimated as the acetic. 
 Common vinegar, excise strength, contains 5 per cent, of such acid as is stated in the 
 above analysis, indicating from 3 to 4 per cent, of table vinegar in the above varieties 
 of beer. 
 
 BICARBONATE OF POTASH AND OF SODA. These salts, so much 
 used in medicine, may, according to M. Behrens, be very readily prepared by gradually 
 adding acetic acid to a strong solution of their carbonates ; that of soda being hot. 
 The carbonic acid, at the moment of its disengagement, by the stronger affinity of the 
 
 E 
 
26 
 
 BISCUITS. 
 
 acetic for the alkalis, combines with a portion of them to form bicarbonates, which 
 fall to the bottom of the vessel in which the mixture is made. The supernatant 
 acetate being separated by decantation, the residuary bicarbonate is to be pressed in 
 linen, washed with ice-cold water, and dried. This ingenious process may be practised 
 by the chamber chemist, but will not afford the bicarbonates at so cheap a rate as the 
 ordinary modes of manufacture. 
 
 BIRDLIME. All the parts of the misletoe contain a peculiar viscid gluey sub- 
 stance, which they yield by decoction, particularly of the bark and green portions ; as 
 also from the expressed juice of the bark or berries, when it is kneaded with the fingers 
 under water. The birdlime is thus obtained in the form of a white opaque mass, 
 sticking to the fingers. It may also be extracted from the berries of the misletoe by 
 means of ether, repeatedly applied, digested with them. It dissolves at first a mixture 
 of green wax and birdlime, but afterwards birdlime alone. By distilling off the ether, 
 the birdlime remains colourless and pure. Birdlime may be considered as a kind of 
 viscid resin which does not dry, and resembling in this respect an ointment of oil or 
 lard and rosin melted together — the old basilicon of the surgeon. Alcohol, even boil- 
 ing hot, dissolves hardly any birdlime ; but merely its waxy impurities, which it de- 
 posits in flocks on cooling. It is soluble in the oils of rosemary and turpentine, as also 
 in petroleum. Heated with the ley of caustic potash, it forms a compound soluble in 
 alcohol. Nitric acid converts it into oxalic acid, and into a fat which solidifies. 
 
 Macaire has examined a substance which exudes from the receptacle and involucre 
 of the atractylis gummifera, and describes it as the pure matter of birdlime, which he 
 styles viscine. It is said to be composed in 100 parts of 75 - 6 carbon, 9*2 hydrogen, 
 and 15*2 oxygen. Common birdlime may be regarded as a mixture of viscine, 
 vegetable mucilage, and vinegar. The young shoots of the ficus elastica afford a milky 
 juice, which is viscine, while the old branches afford a juice rich in caoutchouc. 
 
 BISCUITS. For the following account of the mechanical system of baking 
 biscuits for the royal navy, I am indebted to the ingenious inventor, Thos. Grant, Esq. 
 of Gosport. 
 
 Ships' biscuits are now made by machinery ; and one of the reasons for this has 
 been that the manual preparation of them was too slow and too costly during the 
 last war. A landsman knows very little of the true value of a biscuit : with a 
 seaman, biscuit is the only bread that he eats for months together. There are many 
 reasons why common loaves of bread could not be used during a long voyage : 
 because, containing a fermenting principle, they would soon become musty and unfit 
 for food, if made previous to the voyage ; while the preparation of them on board 
 ship is subject to insuperable objections. Biscuits contain no leaven, and, when well 
 baked throughout, they suffer little change during a long voyage. 
 
 The allowance of biscuit to each seaman on board a queen's ship is a pound per 
 day (averaging six biscuits to the pound). The supply of a man-of-war for several 
 months is, consequently, very large ; and it often happened during the last war that 
 the difficulty of making biscuits fast enough was so great, that at Portsmouth waggon 
 loads were unpacked in the streets and conveyed on board ships. 
 
 We shall now describe the mode of making biscuits by hand ; and afterwards speak 
 of the improved method. The bakehouse at Gosport contained nine ovens, and to 
 each was attached a gang of five men — the " turner," the " mate," the " driver," the 
 "breakman," and the "idleman." The requisite proportions of flour and water were 
 put into a large trough, and the " driver," with his naked arms, mixed the whole up 
 together into the form of dough — a very laborious operation. The dough was then 
 taken from the trough and put on a wooden platform called the break : on this plat- 
 form worked a lever called the break-staff, five or six inches in diameter, and seven 
 feet long ; one end of this was loosely attached by a kind of staple to the wall, and the 
 breakman, riding, or sitting, on the other end, worked this lever to and fro over the 
 dough, by an uncouth jumping or shuffling movement. When the dough had become 
 kneaded by this barbarous method into a thin sheet, it was removed to the moulding- 
 board, and cut into slips by means of an enormous knife ; these slips were then broken 
 into pieces, each large enough for one biscuit, and then worked into a circular form by 
 the hand. As each biscuit was shaped it was handed to a second workman, who 
 stamped the king's mark, the number of the oven, &c, on the biscuit. The biscuit 
 was then docked, that is, pierced with holes by an instrument adapted to the purpose. 
 The finishing part of the process was one in which remarkable dexterity was dis- 
 played. A man stood before the open door of the oven, having in his hand the handle 
 of a long shovel called a peel, the other end of which was lying flat in the oven. 
 Another man took the biscuits as fast as they were formed and stamped, and jerked or 
 threw them into the oven with such undeviating accuracy that they should always fall 
 on the peel. The man with the peel then arranged the biscuits side by side over the 
 whole floor of the oven. Nothing could exceed (in manual labour alone) the regu- 
 
BISCUITS. 
 
 27 
 
 larity with which this was all done. Seventy biscuits were thrown into the oven and 
 regularly arranged in one minute ; the attention of each man being vigorously directed 
 to his own department ; for a delay of a single second on the part of any one man 
 would have disturbed the whole gang. The biscuits do not require many minutes' 
 baking ; and as the oven is kept open during the time that it is being filled, the biscuits 
 first thrown in would be overbaked were not some precaution taken to prevent it. 
 The moulder therefore made those which were to be first thrown into the even larger 
 than the subsequent ones, and diminished the size by a nice gradation. 
 
 The mode in which, since about the year 1831, ships' biscuits have been made by 
 machinery invented by T. T. Grant, Esq., of the Royal Clarence Yard, is this: the 
 meal or flour is conveyed into a hollow cylinder four or five feet long and about 
 three feet in diameter, and the water, the quantity of which is regulated by a guage 
 admitted to it ; a shaft, armed with long knives, works rapidly round in the cylinder, 
 with such astonishing effect that, in the short space of three minutes, 340 pounds 
 of dough are produced, infinitely better made than that mixed by the naked arms of 
 a man. The dough is removed from the cylinder and placed under the breaking- 
 rollers ; these latter, which perform the office of kneading, are two in number, and 
 weigh 15 cwt. each; they are rolled to and fro over the surface of the dough by 
 means of machinery, and in five minutes the dough is perfectly kneaded. The sheet 
 of dough, which is about two inches thick, is then cut into pieces half a yard square, 
 which pass under a second set of rollers, by which each piece is extended to the 
 size of six feet by three, and reduced to the proper thickness for biscuits. 'ihe 
 sheet of dough is now to be cut up into biscuits, and no part of the operation is 
 more beautiful than the mode by which this is accomplished. The dough is brought 
 under a stamping or cutting-out press, similar in effect, but not in detail, to that by 
 which circular pieces for coins are cut out of a sheet of metal. A series of sharp 
 knives are so arranged that, by one movement, they cut out of a piece of dough a 
 yard square about sixty hexagonal biscuits. The reason for a hexagonal (six-sided) 
 shape is, that not a particle of waste is thereby occasioned, as the sides of the hex- 
 agonals accurately fit into those of the adjoining biscuits ; whereas circular pieces 
 cut out of a large surface always leave vacant spaces between. That a flat sheet can 
 be divided into hexagonal pieces without any waste of material is obvious. 
 
 Each biscuit is stamped with the queen's mark, as well as punctured with holes 
 by the same movement which cuts it out of the piece of dough. The hexagonal 
 cutters do not sever the biscuits completely asunder ; so that a whole sheet of them 
 can be put into the oven at once on a large peel or shovel adapted for the purpose. 
 About fifteen minutes are sufficient to bake them ; they are then withdrawn and 
 broken asunder by the hand. 
 
 The corn for the biscuits is purchased at the markets, and cleaned, ground, and 
 dressed, at the government mills ; in quality it is a mixture of fine flour and mid- 
 dlings, the bran and pollard being removed. The ovens for baking are formed of 
 fire-brick and tile, with an area of about 160 feet. About 112 lbs. weight of biscuits 
 are put into the ovens at once. This is called a suit, and is reduced to about 1 1 0 lbs. 
 by the baking. From twelve to sixteen suits can be baked in each oven every day, or 
 after the rate of 224 lbs. per hour. The men engaged are dressed in clean check 
 shirts and white linen trowsers, apron, and cap ; and every endeavour is made to 
 observe the most scrupulous cleanliness. 
 
 We may now make a few remarks on the comparative merits of the hand and the 
 machine processes. If the meal and the water with which the biscuits are made be 
 not thoroughly mixed up, there will be some parts moister than others. Now, it was 
 formerly found that the dough was not well mixed by the arms of the workman ; the 
 consequence of which was that the dry parts became burnt up, or else that the moist 
 parts acquired a peculiar kind of hardness which the sailors called" flint -."these defects 
 are now removed by the thorough mixing and kneading which the ingredients receive 
 by the machine. 
 
 We have seen that 450 lbs. of dough may be mixed by the machine in four minutes, 
 and kneaded in five or six minutes ; we need hardly say how much quicker this is than 
 men's hands could effect it. The biscuits are cut out and stamped sixty at a time, 
 instead of singly : besides the time thus saved, the biscuits become more equally 
 baked, by the oven being more speedily filled. The nine ovens at Gosport used to 
 employ 45 men to produce about 1500 lbs. of biscuit per hour; 16 men and boys will 
 now produce, by the same number of ovens, 2240 lbs. of biscuits (one ton) per hour. 
 
 The comparative expense is thus stated : — Under the old system, wages, and wear 
 and tear of utensils, cost about Is. 6d. per cwt. of biscuit: under the new system, the 
 cost is 5d. 
 
 The bakehouses at Deptford, Gosport, and Plymouth, could produce 7000 or 8000 
 tons of biscuits annually, at a saving of 1 2,000/. per annum from the cost under the 
 
 E 2 
 
28 
 
 BITUMEN. 
 
 old system. The advantages of machine-made over hand-made biscuits, therefore, are 
 many : quality, cleanliness, expedition, cheapness, and independence of government 
 contractors. 
 
 Fig. 7. represents the biscuit machinery, as executed beautifully by Messrs. Rennie, 
 
 7 
 
 Engineers, a is the breaking roller, table and roller; 6, the finishing roller, table and 
 roller ; c, c, docking machines for stamping out the biscuits ; d, mixing machine for 
 making the dough ; e, spur pinion to engine shaft ; f, spur-wheel ; g, g, bevel mitre- 
 wheels to give the upright motion ; h, h, bevel-wheels for working the mixing machine ; 
 i t i, i, ditto for communicating motion to the rolling machines k, the crank shaft ; 
 /, Z, connecting rods ; m, m, pendulums for giving motion to rollers ; n, n, clutches for 
 connecting either half of the machinery to the other. 
 
 BITUMEN. It is a very remarkable fact, in the history of the useful arts, that 
 asphalt, which was so generally employed as a solid and durable cement in the earliest 
 constructions upon record, as in the walls of Babylon, should for so many thousand 
 years have fallen well nigh into disuse among civilised nations. For there is cer- 
 tainly no class of mineral substance so well fitted as the bituminous, by their plasticity, 
 fusibility, tenacity, adhesiveness to surfaces, impenetrability by water, and unchange- 
 ableness in the atmosphere, to enter into the composition of terraces, foot-pavements, 
 roofs, and every kind of hydraulic work. Bitumen, combined with calcareous earth, 
 forms a compact, semi-elastic solid, which is not liable to suffer injury by the greatest 
 alternations of frost and thaw, which often disintegrate in a few years the hardest stone, 
 nor can it be ground to dust and worn away by the attrition of the feet of men and 
 animals, as sandstone, flags, and even blocks of granite are. An asphalt pavement, 
 rightly tempered in tenacity, solidity, and elasticity, seems to be incapable of suffering 
 abrasion in the most crowded thoroughfares ; a fact exemplified of late in a few places 
 in London, but much more extensively, and for a much longer time, in Paris. 
 
 The great Place de la Concorde (formerly Place Louis Quinze) is covered with a 
 beautiful mosaic pavement of asphalte ; many of the promenades on the Boulevards, 
 formerly so filthy in wet weather, are now covered with a thin bed of bituminous 
 mastich, free alike from dust and mud ; the foot-paths of the Pont Royal and Pont 
 Carousel, and the areas of the great public slaughter-houses, have been for several 
 
BITUMEN. 
 
 29 
 
 years paved in a similar manner with perfect success. It is much to be regretted that 
 the Asphalt Companies of London made the ill-judged, and nearly abortive, attempt 
 to pave the carriage-way near the east end of Oxford Street, and especially at a moist 
 season, most unpropitious to the laying of bituminous mastich. Being formed of 
 blocks not more than three or four inches thick, many of which contained much 
 siliceous sand, such a pavement could not possibly resist the crash and vibration of 
 many thousand heavy drays, waggons, and omnibuses daily rolling over it.* This 
 failure can afford, however, no argument against rightly-constructed foot-pavements 
 and terraces of asphalt. Numerous experiments and observations have led me to 
 conclude that fossil bitumen possesses far more valuable properties, for making a 
 durable mastich, than the solid pitch obtained by boiling wood or coal tar. The latter, 
 when inspissated to a proper degree of hardness, becomes brittle, and may be readily 
 crushed into powder ; while the former, in like circumstances, retains sufficient tena- 
 city to resist abrasion. Factitious tar and pitch being generated by the force of fire, 
 seem to have a propensity to decompose by the joint agency of water and air, whereas 
 mineral pitch has been known to remain for ages without alteration. 
 
 Bitumen alone is not so well adapted for making a substantial mastich as the native 
 compound of bitumen and calcareous earth, which has been properly called asphaltic 
 rock, of which the richest and most extensive mine is unquestionably that of the 
 Val-de- Travers, in the canton of Neufchatel. This interesting mineral deposit occurs 
 in the Jurassic limestone formation, the equivalent of the English oolite. The mine 
 is very accessible, and may be readily excavated by blasting with gunpowder. The 
 stone is massive, of irregular fracture, of a liver-brown colour, and is interspersed with 
 a few minute spangles of calcareous spar. -Though it may be scratched with the nail, 
 it is difficult to break by the hammer. When exposed to a very moderate heat it ex- 
 hales a fragrant ambrosial smell, a property which at once distinguishes it from all 
 compounds of factitious bitumen. Its specific gravity is 2*114, water being 1000, 
 being nearly the density of bricks. It may be most conveniently analysed by digesting 
 it in successive portions of hot oil of turpentine, whereby it affords 80 parts of a white 
 pulverulent carbonate of lime, and 20 parts of bitumen in 100. The asphalt rock of 
 Val-de-Travers seems therefore to be far richer than that of Pyrimont, which, ac- 
 cording to the statement in the specification of Claridge's patent, of November, 1837, 
 contains " carbonate of lime and bitumen in about the proportion of 90 parts of car- 
 bonate of lime to about 10 parts of bitumen." 
 
 The calcareous matter is so intimately combined and penetrated with the bitumen, 
 as to resist the action not only of air and water for any length of time, but even of 
 muriatic acid; a circumstance partly due to the total absence of moisture in the 
 mineral, but chiefly to the vast incumbent pressure under which the two materials 
 have been incorporated in the bowels of the earth. It would indeed be a difficult 
 matter to combine, by artificial methods, calcareous earth thus intimately with bitu- 
 men, and for this reason the mastichs made in this way are found to be much more 
 perishable. Many of the factitious asphalt cements contain a considerable quantity 
 of siliceous sand, from which they derive the property of cracking and crumbling down 
 when trodden upon. In fact, there seems to be so little attraction between siliceous 
 matter and bitumen, that their parts separate from each other by a very small disrup- 
 tive force. 
 
 Since the asphalt rock of Val de Travers is naturally rich enough in concrete bitu- 
 men, it may he converted into a plastic workable mastic of excellent quality for foot 
 pavements and hydraulic works at very little expense, merely by the addition of a very 
 small quantity of mineral or coal tar, amounting to not more than 6 or 8 per cent. 
 The union between these materials may be effected in an iron caldron, by the applica- 
 tion of a very moderate heat, as the asphalt bitumen readily coalesces with the tar into 
 a tenacious solid. 
 
 The mode adopted for making the beautiful asphalt pavement at the Place de la 
 Concorde in Paris was as follows : — The ground was made uniformly smooth, either 
 in a horizontal plane or with a gentle slope to carry off the water ; the curb-stones 
 were then laid round the margin by the mason, about 4 inches above the level of 
 the ground. This hollow space was filled to a depth of 3 inches with concrete, 
 containing about a sixth part of hydraulic lime, well pressed upon its bed. The sur- 
 face was next smoothed with a thin coat of mortar. When the whole mass had be- 
 come perfectly dry, the mosaic pattern was set out on the surface, the moulds being 
 formed of flat iron bars, rings, &c. about half an inch thick, into which the fluid mastic 
 was poured by ladles from a cauldron, and spread evenly over. 
 
 The mastic was made in the following way : — The asphalt rock was first of all 
 roasted in an oven, about 10 feet long and 3 broad, in order to render it friable. 
 
 * See the conclusion of this article. 
 
30 
 
 BITUMEN. 
 
 The bottom of the oven was sheet iron, heated below by a brisk fire. A volatile 
 matter exhaled, probably of the nature of naptha, to the amount of one-fortieth the 
 weight of asphalt ; after roasting, the asphalt became so friable as to be easily re- 
 duced to powder, and passed through a sieve, having meshes about one-fourth of an 
 inch square. 
 
 The bitumen destined to render the asphalt fusible and plastic, was melted in small 
 quantities at a time, in an iron cauldron, and then the asphalt in powder was gradually 
 stirred into the amount of 12 or 13 times the weight of bitumen. When the mix- 
 ture became fluid, nearly a bucketful of very small, clean gravel, previously heated 
 apart, was stirred into it ; and, as soon as the whole began to simmer with a treacley 
 consistence, it was fit for use. It was transported in buckets, and poured into the 
 moulds. 
 
 For the reasons above assigned, I consider this addition of rounded, polished, sili- 
 ceous stones to be very injudicious. If any thing of the kind be wanted to give soli- 
 dity to the pavement, it should be a granitic or hard calcareous sand, whose angular 
 form will secure the cohesion of the mass. I conceive, also, that tar, in moderate 
 quantity, should be used to give toughness to the asphaltic combination, and prevent 
 its being pulverised and abraded by friction. 
 
 In the able report of the Bastenne and Gaujac Bitumen Company, drawn up by 
 Messrs. Goldsmid and Russell, these gentlemen have made an interesting comparison 
 between the properties of mineral tar and vegetable tar : the bitumen composed of the 
 latter substance, including various modifications extracted from coal and gas, have, so 
 far as they were able to ascertain, entirely failed. This bitumen, owing to the quali- 
 ties and defects of vegetable tar, becomes soft at 1 15° of Farenheit's scale, and is brittle 
 at the freezing point ; while the bitumen, into which mineral tar enters, will sustain 
 170° of heat, without injury. In the course of the winter, 1837-38, when the cold 
 was at 14|° below Zero, C, the bitumen of Bastenne and Gaujac, with which one side of 
 the Pont Neuf at Paris is paved, was not at all impaired, and would, apparently, have 
 resisted any degree of cold; while that in some parts of the Boulevard, which was 
 composed of vegetable tar, cracked and opened in white fissures. The French Go- 
 vernment, instructed by these experiments, has required, when any of the vegetable 
 bitumens are laid, that the pavement should be an inch and a quarter thick ; whereas, 
 where the bitumen composed of mineral tar is used, a thickness of three-quarters of 
 an inch is deemed sufficient. The pavement of the bonding warehouse at Bordeaux 
 has been laid upwards of 15 years by the Bastenne Company, and is now in a condition 
 as perfect as when first formed. The reservoirs constructed to contain the waters of 
 the Seine at Batignolles, near Paris, have been mounted 6 years, and, notwithstanding 
 the intense cold of the winter of 1837, which froze the whole of their contents into one 
 solid mass, and the perpetual water pressure to which they are exposed, they have not 
 betrayed the slightest imperfection in any point. The repairs done to the ancient for- 
 tifications at Bayonne, have answered so well, that the Government, 2 years ago, 
 entered into a very large contract with the company for additional works, while the 
 whole of the arches of the St. Germain and St. Cloud railways, and the pavements and 
 floorings necessary for these works, are being laid with the Bastenne bitumen. 
 
 The mineral tar in the mines of Bastenne and Gaujac is easily separated from the 
 earthy matter with which it is naturally mixed by the process of boiling, and is then 
 transported in barrels to Paris or London, being laid down in the latter place to the 
 company at 17Z. per ton, in virtue of a monopoly of the article purchased by the com- 
 pany at a sum, it is said, of 8000/. 
 
 Mr. Harvey, the able superintendent of the Bastenne Company, was good enough 
 to supply me with various samples of mineral tar, bitumen, and asphaltic rock for 
 analysis. The tar of Bastenne is an exceedingly viscid mass, without any earthy im- 
 purity. It has the consistence of baker's dough at 60° of Fahrenheit ; at 80° it yields 
 to the slightest pressure of the finger; at 150 degrees it resembles a soft extract; and 
 at 212 degrees it has the fluidity of molasses. It is admirably adapted to give plas- 
 ticity to the calcareous asphalts. 
 
 A specimen of Egyptian asphalt which he brought me, gave, by analysis, the very 
 same composition as the Val de Travers, namely, 80 per cent, of pure carbonate of 
 lime, and 20 of bitumen. A specimen of mastich, prepared in France, was found to 
 consist, in 100 parts, of 29 of bitumen, 52 of carbonate of lime, and 19 of siliceous sand. 
 A portion of stone called the natural Bastenne rock, afforded me 80 parts of gritty 
 siliceous matter and 20 of thick tar. The Trinidad bitumen contains a considerable 
 portion of foreign earthy matter ; one specimen having yielded me 25 per cent, of si- 
 liceous sand ; a second, 28 ; a third, 20 ; and a fourth, 30 : the rehiainder was pure 
 pitch. One specimen of Egyptian bitumen, specific gravity 1 '2, was found to be per- 
 fectly pure, for it dissolved in oil of turpentine without leaving any appreciable 
 residuum. 
 
BITUMEN. 
 
 31 
 
 Robinson's Parisian Bitumen Company use a mastich made with the pitch obtained 
 from boiling coal tar mixed with chalk. One piece laid down by this company at Knights- 
 bridge and another at Brighton, are said to have gone to pieces. The portion of pave- 
 ment laid down by them in Oxford Street, next Charles Street, has been taken up. 
 Claridge's Company have laid down their mastich under the archway of the Horse- 
 Guards, and in the carriage entrance at the Ordnance Office ; the latter has cracked at 
 the junction with the old pavement of Yorkshire curb-stone. The foot-pavement laid 
 down by Claridge's Company at Whitehall has stood well. The Bastenne Company 
 has exhibited the best specimen of asphalt pavement in Oxford Street ; they have laid 
 down an excellent piece of foot-pavement near Northumberland House ; a piece, 40 
 feet by 7, on Blackfriars' Bridge ; they have made a substantial job in paving 830 
 superficial feet in front of the Guard-room at Woolwich, which, though much tra- 
 versed by foot-passengers, and beat by the guard in grounding arms, remains sound ; 
 lastly, the floor of the stalls belonging to the cavalry barracks of the Blues at Knights- 
 bridge, is probably the best example of asphaltic pavement laid down in this country, 
 as it has received no injury from the beating of the horses' feet. 
 
 As the specific gravity of properly made mastich is nearly double that of water, a 
 cubic foot of it will weigh from 125 to 130 lbs. ; and a square foot, three quarters of 
 an inch thick, will weigh very nearly eight pounds. A ton of it will therefore cover 280 
 square feet. The prices at which the Bastenne Bitumen Company sell their products 
 is as follows : — 
 
 Pure Mineral tar, 24/. per ton, or 28s. per cwt. 
 Mastich 81. 8s. per ton, or 10s. per cwt. 
 
 Side Pavement. Roofs and Terraces. 
 
 From 50 to 100 feet, Is. 3d. per foot. - Is. 6d. per foot. 
 
 100 
 
 250 
 
 Is. Id. 
 
 
 Is. Ad. 
 
 250 
 
 500 
 
 lid. 
 
 
 Is. Id. 
 
 500 
 
 750 
 
 lOd. 
 
 
 Is. Od. 
 
 750 
 
 1000 
 
 9d. 
 
 
 1 Id. 
 
 1000 
 
 2000 
 
 8d, 
 
 
 lOd. 
 
 2000 
 
 5000 
 
 Id. 
 
 
 9d. 
 
 i 
 
 Where the work exceeds 5000 feet, contracts may be entered into. 
 For filling up joints of brickwork, &c, from Id. to l\d. per foot, run according to 
 quantity. 
 
 These prices are calculated for half an inch thickness, at which rate a ton will cover 
 420 square feet. 
 
 As the Val de Travers Company engage to lay down their rich asphaltic rock in 
 London at 51. per ton ; and as a mineral tar equal to that of Seissel may probahly be 
 had in England at one fourth of the price of that foreign article, they may afford to lay 
 their mastich three quarters of an inch thick per the thousand feet, including a sub- 
 stratum of concrete, at a rate of fivepence a square foot, instead of fifteenpence, being 
 the rate charged under that condition by the Bastenne Company. 
 
 These charges are for London and its immediate vicinity. 
 
 Report of the experimental Pavements laid down in Oxford Street, from Charles Street to 
 Tottenham Court Road, January, 1839. 
 
 1. Robinson's Parisian bitumen, laid in blocks 12 inches square and 5 inches deep ; 
 the substance is a compound of bitumen, lime, &c, and five granite stones are inserted 
 in the top of each block ; the work is laid in straight courses, the joints cemented with 
 hot bitumen. The quantity of this is 97 square yards, the length is 20 feet, and the 
 price, if adopted, 9s. per square yard. 
 
 2. Same as 1, but the courses laid diagonally. The quantity is 97 square yards, 
 the length is 20 feet. 
 
 3. Granite paving, 9 inches deep, jointed with Claridge's asphalte, the work laid in 
 straight courses. The cost to the parish has been lis. Id. per yard superficial for the 
 stone and laying, &c, no charge being made by Claridge's Company for the asphalte. 
 The quantity is 240 yards, the length 54 feet. 
 
 4. Granite paving, 4i inches deep, jointed with Claridge's asphalte, the work laid in 
 diagonal courses. Cost to the parish 9s. 6d. per square yard. No charge made for 
 the asphalte. The quantity is 88 square yards, the length 20 feet. 
 
 5. The Bastenne Bitumen Company. The blocks are 12 inches long, 6\ wide, and 
 3| deep, with befelled joints, close at bottom, and ± inch open at top ; the joints 
 cemented with h'ot bitumen ; the substance is bituminous, with a very large proportion 
 of granite imbedded in each block; the price, if adopted, 13s. 6d. per square yard; 
 the length, in straight courses, 20 feet. 
 
32 
 
 BLACK PIGMENT 
 
 6. Same as 5, but the courses laid diagonally. The length 40 feet ; the total quan- 
 tity in 5 and 6 is 274 square yards. 
 
 7. Aberdeen granite paving, 9 inches deep ; laid on a concrete bottom, formed of 
 gravel and lime, the joints of the pavement run with hot lime grout, in straight courses. 
 The length is 69 feet ; cost, 16s. 5d. per square yard. 
 
 8. Same as 7, but the courses laid diagonally ; length, 38 feet. 
 
 9. Aberdeen granite paving, 9 inches deep, in straight courses, without a concrete 
 bottom ; joints filled with fine gravel ; cost, 12s. 5d. per yard; length, 24 feet. 
 
 10. The Scotch Asphaltum Company. The work is laid in blocks of divers length, 
 9 inches wide, and 6\ deep ; the side joints are straight, the end joints are bevelled 
 alternately. The work is laid in straight courses, and jointed in Roman cement ; the 
 substance is, apparently, a bituminous matter mixed with fine gravel. The length is 
 50 feet : the number of square yards, 210 ; the price, per yard, if adopted, 13s. 6d. 
 
 11. The wood paving. The blocks are sexagon on the plan, and (with the excep- 
 tion of a few courses that are only 8 inches), 12 inches deep. The work is laid end- 
 ways of the grain; the blocks are mostly 8 inches diameter — a few courses are 7 
 inches. The material is Norway fir ; there is no prepared bottom — the blocks are 
 laid on the plain ground, a small layer of gravel being spread to bed them in. From 
 the west end, 22 rows of courses of blocks are of wood in its natural state ; 31 rows 
 have been Kyanised; 9 rows at the eastern end have been dipped in Claridge's 
 asphalte ; 6 rows have been dipped in a solution prepared by the patentee ; the re- 
 mainder are of wood in the natural state. The length of this piece is 60 feet : the 
 number of yards, 230; price per yard, if approved, 10s. 6d. 
 
 12. Val-de-Travers Company. Blocks in straight courses, 12 inches square, 5 inches 
 deep, with square joints. The substance of the blocks is bituminous, with a very large 
 proportion of granite imbedded in each block, the joints cemented with hot bitumen. 
 The length is 25 feet ; number of square yards 94 ; the work is performed gra- 
 tuitously. 
 
 13. The same company. A layer of clean chippings and hot asphalt poured 
 thereon. The face up with hot asphalt and broken stone imbedded therein. The 
 length is 25 feet : number of yards, 94 ; the work is gratuitous. 
 
 14. Same as 9. The length 47 feet. 
 
 By order of the Committee, 
 
 H. Kensett, Chairman. 
 
 Statement of the Number of Carriages passing through Oxford Street at the under- 
 named Times and Places. 
 
 Date 
 1839. 
 
 Time. 
 
 Place. 
 
 Gents. 2- Wheel. | 
 
 Gents 4-Wheel. 
 
 Omnibuses. 
 
 1 2 Wheel Hackney 
 Carriages. 
 
 4-Wheel Hackney 
 Carriages. 
 
 Stage Coaches. 
 
 Waggons, 
 Drays, &c. 
 
 Light Carts 
 and Sundries. 
 
 Total. 
 
 Jan. 16. 
 
 6 in the morning till 12 at night. 
 
 by the Pantheon. 
 
 347 
 
 935 
 
 890 
 
 621 
 
 752 
 
 91 
 
 372 
 
 1507 
 
 5515 
 
 18. 
 
 do. 
 
 by Stratford Place. 
 
 254 
 
 603 
 
 1213 
 
 401 
 
 728 
 
 89 
 
 472 
 
 993 
 
 4753 
 
 22. 
 
 do. 
 
 by Newman Street. 
 
 339 
 
 1241 
 
 1015 
 
 584 
 
 1288 
 
 85 
 
 958 
 
 1382 
 
 6992 
 
 26. 
 
 do. 
 
 by Stratford Place. 
 
 371 
 
 666 
 
 1337 
 
 542 
 
 762 
 
 92 
 
 881 
 
 1292 
 
 5943 
 
 26. 
 
 1 2 at night till 6 in the morning. 
 
 do. 
 
 
 4 
 
 1 
 
 82 
 
 139 
 
 2 
 
 38 
 
 58 
 
 324 
 
 BLACK DYE. The mordant much employed in some parts of Germany for this 
 dye, with logwood, galls, sumach, &c, is Iron- Alum, so called on account of its having 
 the crystalline form of alum, though it contains no alumina. It is prepared by dis- 
 solving 78 pounds of red oxide of iron in 1 17 pounds of sulphuric acid, diluting this com- 
 pound with water, adding to the mixture 87 pounds of sulphate of potash, evaporating 
 the solution to the crystallizing point. This potash -sulphate of iron has a fine amethyst 
 colour when recently prepared ; and though it gets coated in the air with a yellowish 
 crust, it is none the worse on this account. As a mordant, a solution of this salt, in 
 from 6 to 60 parts of water, serves to communicate and fix a great variety of uniform 
 ground colours, from light grey to brown, blue, or jet black, with quercitron, galls, log- 
 wood, sumach, &c, separate or combined. The above solution may be usefully modi- 
 fied by adding to every 10 pounds of the iron-alum, dissolved in 8 gallons (80 pounds) 
 of warm water, 10 pounds of acetate (sugar) of lead, and leaving the mixture, after 
 careful stirring, to settle. Sulphate of lead falls, and the oxide of iron remains com- 
 bined with the acetic acid and the potash. After passing through the above mordant, 
 the cotton goods should be quickly dried. 
 
 BLACK PIGMENT. A fine lamp-black is obtained by the combustion of a 
 thick torch of coal-gas, supplied with a quantity of air adequate to burn only its hydro- 
 
BONE BLACK. 
 
 33 
 
 gen. In this case, the whole of its carbon is deposited in the form of a very fine black 
 powder of extreme lightness. This black is used in making the better qualities of 
 printers' ink. 
 
 BLACKING FOR SHOES. ( Cirage des bottes, Fr. ; Schuhschwdrze.) 
 
 The following prescription for making liquid and paste blacking is given by William 
 Br yant and Edward James, under the title of a patent, dated December, 1836. Their 
 improvement consists in the introduction of caoutchouc, with the view, possibly, of 
 making the blacking, waterproof : — 
 
 1 8 ounces of caoutchouc are to be dissolved in about 9 pounds of hot rape oil. To 
 this solution 60 pounds of fine ivory black, and 45 pounds of molasses, are to be added, 
 along with 1 pound of finely ground gum arabic, previously dissolved in 20 gallons of 
 vinegar, of strength No. 24. These mixed ingredients are to be finely triturated in a 
 paint mill till the mixture becomes perfectly smooth. To this varnish 12 pounds of 
 sulphuric acid are to be now added in small successive quantities, with powerful stir- 
 ring for half an hour. The blacking thus compounded is allowed to stand for 14 days, 
 it being stirred half an hour daily ; at the end of which time, 3 pounds of finely ground 
 gum arabic are added ; after which the stirring is repeated half an hour every day for 
 14 days longer, when the liquid blacking is ready for use. 
 
 In making the paste blacking, the patentees prescribe the above quantity of India 
 rubber oil, ivory black, molasses, and gum arabic, the latter being dissolved in only 12 
 pounds of vinegar. These ingredients are to be well mixed, and then ground together 
 in a mill till they form a perfectly smooth paste. To this paste 12 pounds of sulphuric 
 acid are to be added in small quantities at a time, with powerful stirring, which is to be 
 continued for half an hour after the last portion of the acid has been introduced. This 
 paste will be found fit for use in about 7 days. 
 
 BLEACHING OF PAPER. The following are the proportions of liquid chlo- 
 ride of lime, at 10° of Gay Lussac's Chlorometre, employed for the different sorts of rags, 
 consisting of 2 piles, or 200 pounds French. 
 
 Cotton. litres. 
 
 No. 1. Fine cotton rags - - - - - 10 
 
 2. Clean calicoes - - - - - -12 
 
 3. - - - - - 14 
 
 4. White dirty calico, coarse cotton - - 1 6 
 
 5. Coarse cotton - - - - - -18 
 
 6. Grey, No. 1. - - - - - , - 20 
 
 No. 2. - - - - - - 22 
 
 Saxon grey - - - - - 24 
 
 No. 2. - - - - - 26 
 
 Pale white and half.white shades - - - 28 
 
 Saxon blues ; pale pink, dark blue, velvet - - 32 
 
 It is considered to be much better to bleach the fine rags with liquid chloride of lime, 
 and not with chlorine gas, because they are less injured by the former, and afford a 
 paper of more nerve, less apt to break, and more easily sized. But the coarse or grey 
 rags are much more economically bleached with the gaseous chlorine, without any risk 
 of weakening the fibre too much. Bleaching by the gas is performed always upon the 
 sorted rags, which have been boiled in an alkaline lye, and torn into the fibrous state. They 
 are subjected to the press, in order to form them into damp cakes, which are broken in 
 pieces and placed in large rectangular wooden cisterns. The chlorine gas is introduced 
 by tubes in the lid of the cistern, which falls down by its superior gravity, acting always 
 more strongly upon the rags at the bottom than those above. 
 
 When the chlorine, disengaged from 150 kilogrammes (330 lbs.) of manganese and 
 500 kilos, of muriatic acid, is made to act upon 2,500 kilos, of the stuff (supposed dry), 
 it will have completed its effect in the course of a few hours. The quantity of gaseous 
 chlorine is equal to what is contained in the quantity of chloride of lime requisite to pro- 
 duce a like bleaching result. The bleached stuff should be forthwith carefully washed, 
 to remove all the muriatic acid produced from the chlorine ; for if any of this remain 
 in the paper, it destroys lithographic stones, and weakens common ink. 
 
 BONE BLACK, or animal charcoal restored. A process for this purpose was made 
 the subject of a patent by Messrs. Bancroft and Mac Innes of Liverpool, which consists 
 in washing the granular charcoal, or digesting it when finely ground, with a weak solu- 
 tion of potash or soda, of specific gravity 1 06. The bone black which has been used 
 in sugar refining may be thus restored, but it should be first cleared from all the soluble 
 filth by means of water. 
 
 Mr. F. Parker's method, patented in June 1839, for effecting a like purpose, is, by a 
 fresh calcination, as follows : — 
 
 F 
 
34 
 
 BRASS, YELLOW. 
 
 Fig. 8. represents a front section of the furnace and retort; and Jig. 9. is a trans- 
 verse vertical section of the same, a is a retort, surrounded by the flues of the furnace 
 
 b ; c is a hopper or chamber, to which a constant fresh supply of the black is furnished, 
 as the preceding portion has been withdrawn, from the lower part of a. d is the cool- 
 ing vessel, which is connected to the lower part of the retort a by a sand joint, e. The 
 cooler d is made of thin sheet iron, and is large ; its bottom is closed with a slide plate, 
 /. The black, after passing slowly through the retort a into the vessel d, gets so much 
 cooled by the time it reaches /, that a portion of it may be safely withdrawn, so as to 
 allow more to fall progressively down ; g is the charcoal-meter, with a slide door. 
 
 BOOKBINDING, Mechanical; — An ingenious invention, for which Mr. Thomas 
 Richards, of Liverpool, Bookbinder, obtained a patent in April, 1842. He employs, 
 1st, a mechanism to sew, weave, or bind a number of sheets together to form a book, 
 instead of stitching them by hand ; 2dly, a table which slides to and fro to feed or 
 supply each sheet of paper separately into his machine ; also needle bars, or holders, 
 to present needles with the requisite threads, for stitching such sheets as they are sup- 
 plied with in succession. He has, moreover, a series of holding ringers, or pincers, suit- 
 ably provided with motions, to enable them to advance and clasp the needles, draw them 
 through the sheets of paper, and return them into their respective holders, after thread- 
 ing or stitching the sheet ; lastly, there are arms or levers for delivering each sheet 
 regularly upon the top of the preceding sheets, in order to form a collection or book of 
 such sheets, ready for boarding and finishing. A minute description of the whole 
 apparatus, with plates, is given in Newton's Journal, C. S .xxiii. 157. 
 
 BORAC1C ACID. Imported for consumption in 1839, 1,243,868 lbs. ; in 1840, 
 524,205 lbs. 
 
 BORAX. Imported for home consumption in 1839, 498,079 lbs. ; in 1840, 
 319,126 lbs. 
 
 BRANDY. Imported for consumption in 1839, 167,756 galls. ; in 1840, 1,108,578 
 galls. : duty, 1/. 2s. \0d. per imperial proof gallon. 
 
 BRASS, YELLOW. The following table exhibits the composition of several 
 varieties of this species of brass. No. 1, is a cast brass of uncertain origin ; 2. the 
 brass of Jemappes; 3. the sheet brass of Stolberg, near Aix-la-Chapelle ; 4 and 5. 
 the brass for gilding, according to D' Arcet ; 6. the sheet brass of Romilly ; 7. English 
 brass wire; 8. Augsburg brass wire; 9, brass wire of Neustadt-Eberswald, in the 
 neighbourhood of Berlin, 
 
 
 I. 
 
 2. 
 
 3. 
 
 4. 
 
 5. 
 
 6. 
 
 7. 
 
 8. 
 
 9. 
 
 Copper 
 
 61-6 
 
 64-6 
 
 64-8 
 
 63-70 
 
 64-45 
 
 70-1 
 
 70-29 
 
 71-89 
 
 70-16 
 
 Zinc 
 
 353 
 
 337 
 
 32-8 
 
 33-55 
 
 32-44 
 
 29-9 
 
 29-26 
 
 27*63 
 
 27-45 
 
 Lead 
 
 29 
 
 1-4 
 
 2-0 
 
 0-25 
 
 2-86 
 
 
 0-28 
 
 
 0-20 
 
 Tin 
 
 0-2 
 
 0-2 
 
 0-4 
 
 2-50 
 
 0*25 
 
 
 0-17 
 
 0-85 
 
 0-79 
 
 
 100-0 
 
 999 
 
 100-0 
 
 100-00 
 
 100-00 
 
 
 100-00 
 
 100-37 
 
 98-60 
 
BREAD. 
 
 35 
 
 The mean proportion of the metals in yellow brass is SO zinc to 70 copper. 
 
 Tombak, or Red Brass, in the cast state, is an alloy of copper and zinc, containing 
 not more than 20 per cent, of the latter constituent. The following varieties are 
 distinguished : — 1, 2, 3, tombak for making gilt articles ; 4. French tombak for sword- 
 handles, &c. ; 4. tombak of the Okar, near Goslar, in the Hartz ; 5. yellow tombak of 
 Paris for gilt ornaments ; 6. tombak for the same purpose from a factory in Hanover ; 
 8. chrysochalk ; 9. red tombak from Paris; 10. red tombak of Vienna. 
 
 
 1. 
 
 2. 
 
 3. 
 
 4. 
 
 5. 
 
 6. 
 
 7. 
 
 8. 
 
 9. 
 
 10. 
 
 Copper 
 
 82-0 
 
 82 
 
 82-3 
 
 80 
 
 85 
 
 85-3 
 
 86 
 
 90-0 
 
 92 
 
 97-8 
 
 Zinc 
 
 18-0 
 
 18 
 
 17-5 
 
 17 
 
 15 
 
 14-7 
 
 14 
 
 7-9 
 
 8 
 
 2-2 
 
 Lead 
 
 1-5 
 
 3 
 
 
 
 
 
 
 1-6 
 
 
 
 Tin 
 
 3-0 
 
 I 
 
 0-2 
 
 3 
 
 trace. 
 
 
 
 
 
 
 
 104-5 
 
 104 
 
 100-0 
 
 100 
 
 100 
 
 100-0 
 
 100 
 
 99-5 
 
 100 
 
 100-0 
 
 Pinchbeck is made of 2 parts copper and 1 yellow brass ; 
 
 Prince's metal ... 3 1 zinc. 
 
 Mannheim gold (semilor), 28 copper, 12 yellow brass, 3 tin. 
 
 Cast white metal buttons are made of an alloy of 32 parts brass (yellow), 4 parts 
 zinc, and 2 tin. 
 
 The specific gravity of brass is greater than the mean density of its constituents ; 
 varying from 7*82 to 8 '73, according to the proportion of zinc to copper. Sheet brass 
 varies from 8*52 to 8*62; brass wire from 8*49 to 8 '73. Brass heated and quickly 
 cooled becomes somewhat less dense. The specific gravity of sheet tombak (81 -25 
 copper +18*75 zinc) is 8*788 ; of tombak wire (87*5 copper+12*5 zinc) has been 
 found so great as 9*00. 
 
 BREAD. I believe it may be safely asserted that the art of baking bread, pastry, 
 and confectionary, is carried in Paris to a pitch of refinement which it has never 
 reached in London. I have never seen here any bread which, in flavour, colour, and 
 texture, rivalled the French pain de gruau. In fact, our corn monopoly laws prevent 
 us from getting the proper wheat for preparing, at a moderate price, the genuine 
 semoule out of which that bread is baked. Hence, the plebeian bourgeois can daily 
 grace his table with a more beautiful piece of bread than the most affluent English 
 nobleman. The French process of baking has been recently described, with some 
 minuteness, by their distinguished chemist, M. Dumas*, and it merits to be known in 
 this country. 
 
 At each operation, the workman (petrisseur) pours into the kneading trough the 
 residuary leaven of a former kneading, adding the proportion of water which practice 
 enjoins, and diffuses the leaven through it with his hands. He then introduces into 
 the liquid mass the quantity of flour destined to form the sponge (pate). This flour 
 is let down from a chamber above, through a linen hose (matiche), which may be shut 
 by folding it up at the end. 
 
 The workman now introduces the rest of the flour by degrees, diffusing and 
 mingling it, in a direction from the right to the left end of the trough. When he has 
 thus treated the whole mass successively, he repeats the same manipulation from left 
 to right. These operations require no little art for their dextrous performance ; hence 
 they have the proper name assigned respectively to each, of frasage and contre- 
 frasage. The workman next subjects the dough to three different kinds of movement, 
 in the kneading process. He malaxates it; that is, works it with his hands and 
 fingers, in order to mix very exactly its component parts, while he adds the requisite 
 quantity of flour. He divides it into six or seven lumps (pdtons), each of which he 
 works successively in the same manner. Then he seizes portions of each, to draw 
 them out, taking only as much as he can readily grasp in his hands. When he has 
 thus kneaded the different lumps, he unites them into one mass, which he extends and 
 folds repeatedly back upon itself. He then lifts up the whole at several times, and 
 dashes it forcibly against the kneading trough, collecting it finally at its left end. 
 The object of these operations is to effect an intimate mixture of the flour, the water, 
 and the leaven. No dry powdery spots, called marrons, should be left in any part of 
 the dough. 
 
 The kneader has now completed his work ; and after leaving the dough for some time 
 at rest, he turns it upside down. He lays the lumps, of a proper weight, upon a 
 table, rolls them out, and dusts them with a little flour. He next turns over each 
 lump, and puts it in its panneton, where he leaves it to swell. If the flour be of good 
 
 * Traite ile Chimie appliquee aux Arts, vi. p. 409. 
 F 2 
 
36 
 
 BREAD. 
 
 quality, the dough be well made, and the temperature be suitable, the lumps will 
 swell much and uniformly. If after the surface has risen, it falls to a considerable 
 extent, the flour must be bad, or it must contain other substances, as potato starch, 
 bean meal, &c. 
 
 Whenever the oven is hot enough, and the dough sufficiently fermented, it is subjected 
 to the baking process. Ovens, as at present constructed, are not equably heated 
 throughout, and are particularly liable to be chilled near the door, in consequence of 
 its being occasionally opened and shut. To this cause M. Dumas ascribes many of the 
 defects of ordinary bread; but he adds, that by adopting the patent invention of 
 M. Mouchot these may be obviated. This is called the improved bakery, boulangerie 
 perfectionnee. ( 
 
 Fig. 10. is a ground plan of the aerothermal bake-house, the granaries being in the 
 
 10 
 
 upper stories, and not shown here, b, b are the ovens ; c, the kneading machine ; d, 
 the place where the machinery is mounted for hoisting up the bread into the store 
 room above ; e, a space common to the two ovens, into which the hot air passes ; f, the 
 place of a wheel driven by dogs, for giving motion to the kneading machine. 
 
 Fig. 11. is a longitudinal section of the oven ; A, the grate where coke or even pit 
 coals may be burned ; B, B, void spaces which, becoming heated, serve for warming 
 small pieces of dough in ; c, c are flues for conducting the smoke, &c. from the fire- 
 place ; D, seen in Jig. 12., is the chimney for carrying off the smoke transmitted by the 
 flues ; E, E, void spaces immediately over the flues, and beneath the sole, F, F, of the 
 oven. By this arrangement the air, previously heated, which arrives from the void 
 spaces B through the flues c, c, gets the benefit of the heat of the flame which circu- 
 lates in these flues, and, after getting more heated in the spaces E, E, ascends through 
 channels into the oven F, F, upon the sole of which the loaves to be baked are laid. 
 The hot air is admitted into it through the passages a, a, being drawn from the reser- 
 voirs B, B, B, and also by the passage d, d, drawn from the reservoirs E, E. The 
 sole is likewise heated by contact with the hot air contained in the space E, E, placed 
 immediately below it. The hot air, loaded with moisture, issues by the passage b, 6, 
 and returns directly into the reservoir B, B. G, G, an enclosed space directly over 
 the oven, to obstruct the dissipation of its heat ; g, vault of the fire-place. Fig. 12., a 
 transverse section through the middle of the oven. Fig. 13., the kneading machine, a 
 longitudinal section passing through its axis ; P, P, the contour of the machine, made 
 of wood, and divided into three compartments for the reception of the dough. The 
 wooden bars o, o are so placed in the interior of the compartments, as to divide the 
 dough whenever the cylinder is made to revolve. One portion, D, of the cylinder may 
 be opened and laid over upon the other by means of a hinge joint, when the dough and 
 flour are introduced. A, B, C, the three compartments of the machine, two for making 
 the dough, and one for preparing the sponge, called levain, or leaven, by the French, a, a 
 is the pulley which receives its motion from the engine, and transmits it to the cylinder 
 
BREAD. 
 
 37 
 
 through the pinion b, and the spur-wheel e ; d, d, the fly-wheel to regulate the motion ; 
 g, a brake to act upon the fly d, by means of a lever h; i, the pillar of the fly-wheel. 
 
 11 
 
 There is a ratchet wheel counter for numbering the turns of the kneading machine, but 
 it cannot be shown in this view ; n, cross bars of wood, which are easily removed when 
 the cylinder is opened ; they divide the dough. 
 
 Each of the three compartments of the kneader (fig. 13.) is furnished at pleasure 
 with two bars fixed crosswise, but which may be easily removed, whenever the 
 
38 BREAD. 
 
 cylinder is opened. These bars constitute the sole agents for drawing out the dough. 
 
 In a continuous operation, the leaven is constantly prepared in the compartment A ; 
 with which view there is put into it — 
 
 1 25 kilogrammes of ordinary leaven or yeast. 
 67 ----- - flour. 
 
 33 water. 
 
 In all 225 kilogrammes. 
 
 The person in charge of the mechanical kneader shuts down its lid, and sets it 
 a-going. At the end of about seven minutes, he hears the bell of the counter sound, 
 announcing that the number of revolutions has been sufficient to call for an inspection 
 of the sponge, in regard to its consistence. The cylinder is therefore opened, and 
 after verifying the right state of the leaven, and adding water to soften, or flour to 
 stiffen it, he closes the lid, and sets the machine once more in motion. In ten minutes 
 more the counter sounds again, and the kneading is completed. The 450 kilo- 
 grammes of leaven obtained from the two compartments are adequate to prepare 
 dough enough to supply alternately each of the two ovens. For this purpose 75 
 kilogrammes of leaven are taken from each of the two compartments A and A', and 
 placed in the intermediate compartment B. The whole leaven is then 75 + 75=150 
 kilogrammes; to which are added 100 kilogs. of flour and 50 of water=150, so that 
 the chest contains 300 kilogrammes. There is now replaced in each of the cavities A 
 and A' the primitive quantity, by adding 50 kilogrammes of flour and 25 of 
 water = 75. 
 
 The cylinder is again set a-going ; and, from the nature of the apparatus, it is 
 obvious that the kneading takes place at once on the leavens A and A', and on the 
 paste B; which last is examined after 7 minutes, and completed in 10 more =17, at 
 the second sound of the counter-bell. 
 
 The kneader is opened, the paste on the sides and on the bars is gathered to the 
 bottom by means of a scraper. The whole paste of the chest B being removed, 150 
 kilogs. of the leaven are taken, to which 1 50 kilogs. of flour and water are added to 
 prepare the 300 kilogs. of paste destined for the supply of the oven No. 2. These 
 75 kilogs. of leaven from each compartment are replaced as before, and so on in suc- 
 cession. 
 
 The water used in this operation is raised to the proper temperature, viz. 25° or 
 30° C. (77° or 86° F.) in cold weather, and to about 68° F. in the hot season, by 
 mixing common cold water with the due proportion of water maintained at the tem- 
 perature of about 160° F., in the basin F placed above the ovens. 
 
 Through the water poured at each operation upon the flour in the compartment B, 
 there is previously diffused from 200 to 250 grammes of fresh leaven, as obtained from 
 the brewery, after being drained and pressed ( German yeast). This quantity is 
 sufficient to raise properly 300 kilogs. of dough. As soon as this dough is taken out 
 of the kneader, as stated above, and while the machine goes on to work, the quantity 
 requisite for each loaf is weighed, turned about on the table D, to give it its round or 
 oblong form, and there is impressed upon it with the fore-arm, or roller, the cavity 
 which characterises cleft loaves. All the lots of dough of the size of one kilog., 
 called cleft loaves {pains fendus) are placed upon a cloth, a fold of which is raised 
 between two loaves, the cloth being first spread upon a board ; which thus charged 
 with 10 or 15 loaves is transferred to the wooden shelves G G in front of the oven. 
 The Avhole of them rise easily under the influence of the gentle temperature of this ante- 
 chamber or four nil. Whenever the dough loaves are sufficiently raised here, they are 
 put into the oven, a process called enfournement in France ; which consists in setting 
 each loaf on a wooden shovel dusted with coarse flour, and placing it thereby on the 
 sole of the oven, close to its fellow, without touching it. This operation is made easy, in 
 consequence of the introduction of a long jointed gas-pipe and burner into the interior 
 of the oven, by the light of which all parts of it may be minutely examined. The oven 
 
BREAD. 
 
 39 
 
 is first kept moderately hot, by shutting the dampers ; but whenever the thermometer 
 attached to it indicates a temperature of from 300° to 290° C. (572° to 554° F.), 
 the dampers or registers are opened, to restore the heat to its original degree, by 
 allowing of the circulation of the hot air, which rises from the lower cavities around 
 the fire-place into the interior of the oven. When the baking is completed the gas 
 light, which had been withdrawn, is again introduced into the oven, and the bread is 
 taken out ; called the process of defournernent. If the temperature have been main- 
 tained at about 300° C, the 300 kilogs. of dough divided into loaves of one kilog. 
 (2ilbs. avoirdupois) will be baked in 27 minutes. The charging having lasted 10 
 minutes, and the discharging as long, the baking of each batch will take up 47 minutes. 
 But on account of accidental interruptions, an hour may be assigned for each charge 
 of 260 loaves of 1 kilog. each ; being at the rate of 6240 kilogs. (or 6*75 tons) of bread 
 in 24 hours. 
 
 Although the outer parts of the loaves be exposed to the radiation of the walls, 
 heated to 280° or 300° C., and undergo therefore that kind of caramelization (charring) 
 which produces the colour, the taste, and the other special characters of the crust, yet 
 the inner substance of the loaves, or the crumb, never attains to nearly so high a tem- 
 perature ; for a thermometer, whose bulb is inserted into the heart of a loaf, does not 
 indicate more than 100° C. (212° F.). 
 
 The theory of panification (bread-baking) is easy of comprehension. The flour 
 owes this valuable quality to the gluten, which it contains in greater abundance than 
 any of the other cerealia (kinds of corn). This substance does not constitute, as had 
 been heretofore imagined, the membranes of the tissue of the perisperm of the wheat ; 
 but is enclosed in cells of that tissue under the epidermic coats, even to the centre of 
 the grain. In this respect the gluten lies in a situation analogous to that of the starch, 
 and of most of the immediate principles of vegetables. The other immediate principles 
 which play a part in panification are particularly the starch and the sugar ; and they 
 all operate as follows : 
 
 The diffusion of the flour through the water, hydrates the starch and dissolves the 
 sugar, the albumen, and some other soluble matters. The kneading of the dough, by 
 completing these reactions through a more intimate union, favours also the fer- 
 mentation of the sugar, by bringing its particles into close contact with those of the 
 leaven or yeast ; and the drawing out and malaxating the dough softens and stratifies it, 
 introducing at the same time oxygen to aid the fermentation. The dough, when 
 distributed and formed into loaves, is kept some time in a gentle warmth, in the folds 
 of the cloth, pans, &c, a circumstance propitious to the dev elopement of their volume 
 by fermentation. The dimensions of all the lumps of dough now gradually enlarge, 
 from the disengagement of carbonic acid in the decomposition of the sugar ; which gas 
 is imprisoned by the glutinous paste. Were these phenomena to continue too long, 
 the dough would become too vesicular ; they must, therefore, be stopped at the 
 proper point of sponginess, by placing the loaf lumps in the oven. Though this 
 causes a sudden expansion of the enclosed gaseous globules, it puts an end to the fer- 
 mentation, and to their growth ; as also evaporates a portion of the water. 
 
 The fermentation of a small dose of sugar is, therefore, essential to true bread- baking ; 
 but the quantity actually fermented is so small as to be almost inappreciable. It seems 
 probable that in well-made dough the whole carbonic acid that is generated remains in 
 it ; amounting to one-half the volume of the loaf itself at its baking temperature, or 212°. 
 It thence results that less than one-hundredth part of the weight of the flour is all the 
 sugar requisite to produce well-raised bread. What egregious folly was it, therefore, to 
 mount the bakery in Chelsea, twelve years ago, at an expense of 20,000/., for the pur- 
 pose of catching the volatile spirits in their escape from the loaves in the oven — or, as 
 it was vulgarly termed, " taking the gin out of the bread ! " whereas it was nothing but 
 taking the cash out of the pockets of the pseudo-chemical visionaries who swarm in 
 this metropolis. 
 
 The richness or nutritive powers of sound flour and also of bread are proportional to 
 the quantity of gluten they contain. It is of great importance to determine this point, 
 for both of these objects are of enormous value and consumption; and it may be accom- 
 plished most easily and exactly by digesting in a water-bath, at the temperature of 167° 
 F., 1000 grains of bread (or flour) with 1000 grains of bruised barley-malt, in 5000 
 grains, or in a little more than half a pint, of water. When this mixture ceases to take a 
 blue colour from iodine (that is, when all the starch is converted into soluble dextrine) 
 the gluten left unchanged may be collected on a filter cloth, washed, dried at a heat of 
 212°, and weighed. The colour, texture, and taste of the gluten ought also to be 
 examined, in forming a judgment of good flour, or bread. 
 
 Independently of the skill of the baker, bread varies in quality according to the 
 quantity of water and gluten it contains. A patent of German or French origin was 
 obtained here a few years ago, for manufacturing loaf-bread by using thin boiled flour- 
 
40 
 
 BRICKS. 
 
 paste instead of water for setting the sponge, that is, for the preliminary dough fermen- 
 tation. By this artifice, 104 loaves of 4 lbs. each could be made out of a sack of flour, 
 instead of 94, as in ordinary baking ; because the boiled paste gave a water-keeping 
 faculty to the bread in that proportion. But this hydrated bread was apt to spoil in 
 warm weather, and became an unprofitable speculation to all concerned. 
 
 Bread and flour are often adulterated in France with potato starch, but almost nevdr, 
 I believe, in this country. This sophistication is easily detected by the microscope, on 
 account of the peculiar ovoid shape and the large size of the particles of the potato 
 fecula. Horse-bean flour gives to wheaten bread a pinkish tint. In spoiled flour 
 (such as is too often used, partially at least, by our inferior bakers) the gluten some- 
 times disappears altogether, and is replaced by ammoniacal salts.* In this case quick- 
 lime separates ammonia from the flour without heat ; in flour slightly damaged, or 
 ground from damaged wheat, the gluten present is deprived of its elasticity, and is 
 softer than in the natural state. On this account the gluten test of M. Boland is 
 valuable. It consists in putting some gluten into the bottom of a copper tube, and 
 heating that tube in an oven, or in oil at a temperature of 284° F. The length to 
 which the cylinder of gluten expands is proportional to and indicates its quality. 
 
 It appears that a French sack of flour, which weighs 159 kilogrammes, affords from 
 102 to 106 loaves of 2 kilogrammes each : and therefore, 
 
 ]59 : 52-0 :: 280 : 91*6; that is, if 159 kilogs. or lbs. afford 52 loaves of 4 kilogs. 
 or lbs., 280 lbs., a sack English, should afford 91*6 loaves of 4 lbs. each; but our 
 bakers usually make out 94 loaves, which are rated at 4 pounds, though they seldom 
 weigh so much. The loaves of a baker in my neighbourhood, who supplied my family 
 with bread for some time, were found on trial to be from 6 to 8 oz. deficient in weight ; 
 when challenged for this fraud, he had the effrontery to palliate it by alleging that all 
 his neighbour bakers did the same. It must be borne in mind that a Paris loaf of 2 lbs. 
 or 2 kilogs. contains more dry farina than a London loaf of like weight ; for it contains, 
 from its form and texture, more crust. The crumb is to the crust in the Paris long 
 loaves, as 25 to 75, or 1 to 3 : in our quartern loaves it is as 18 or 20 to 100. 
 
 M. Dumas gives the following Table : — 
 
 Weight of a 
 Sack of Flour. 
 
 Number of 
 Loaves. 
 
 Weight of the 
 Bread. 
 
 Increase of 
 Weight of flour. 
 
 Ratio of dry flour 
 = 1, to Bread. 
 
 159 Kilogs. 
 
 102 
 
 202 Kilogs. 
 
 1-283 
 
 
 159 do. 
 
 104 
 
 208 .do. 
 
 1-300 
 
 1 s 1 60 
 
 159 do. 
 
 106 
 
 212 do. 
 
 1 -333 
 
 
 Thus it would appear that the mean yield would correspond to 130 kilogs. of bread 
 for 100 of the flour employed; and admitting that common flour contains 0 1 7 of 
 water, the product would be equivalent to 150 of bread for 100 of flour absolutely dry. 
 The whole loaf contains 66 per cent, of dry substance, and the crumb only 44. 
 
 BRICKS. Mr. F. W. Simms, C. E., communicated to the Institution of Civil En- 
 gineers, in April and May, 1843, an account of the process of brick-making for the 
 Dover railway. The plan adopted is called slop-moulding, because the mould is dipped 
 into water before receiving the clay, instead of being sanded as in making sand-stock 
 bricks. The workman throws the proper lump of clay with some force into the mould, 
 presses it down with his hands to fill the cavities, and then strikes off" the surplus clay 
 with a stick. An attendant boy, who has previously placed another mould in a water 
 trough by the side of the moulding table, takes the mould just filled, and carries it to 
 the floor, where he carefully drops the brick from the mould on its flat side, and leaves 
 it to dry ; by the time he has returned to the moulding table, and deposited the empty 
 mould in the water trough, the brickmaker will have filled the other mould, for the 
 boy to convey to the floor, where they are allowed to dry, and are then stacked in rea- 
 diness for being burned in clamps or kilns. The average product is shown in the fol- 
 lowing table : — , 
 
 Force employed. 
 
 Area of land. 
 
 Duration of season. 
 
 Produce per week. 
 
 Produce per season. 
 
 1 moulder 
 1 temperer 
 1 wheeler - * 
 I carrier boy - 
 1 picker boy - J 
 
 Roods. Perches. 
 2 14£ 
 
 Weeks. 
 22 
 
 Bricks. 
 16,100 
 
 Bricks. 
 354,200 
 
 * Dumas, Chimie Appliquee, vi. 425. 
 
BRICKS. 
 
 41 
 
 It appears that while the produce in sand-stock bricks is to that of slop-bricks in the 
 same time as 30 to 1 6, the amount of labour is as 7 to 4 ; while the quantity of land, 
 and the cost of labour per thousand, is nearly the same in both processes. The quan- 
 tity of coal consumed in the kiln was at the rate of 10 cwt. 8lbs. per thousand bricks. 
 The cost of the bricks was 21. Is. 6d. per thousand. The slop-made bricks are 
 fully 1 pound heavier than the sand-stock. Mr. Bennett stated to the meeting-, that 
 at his brick-field at Cowley, the average number of sand-stock bricks moulded was 
 32,000 ; but that frequently so many as 37,X)00, or even 50,000, were formed. The 
 total amount in the shrinkage of his bricks was j| 0 f an inch upon 10 inches in length; 
 but this differed with the different clays. Mr. Simms objected to the use of machi- 
 nery in brick-making, because it caused economy only in the moulding, which con- 
 stituted no more than about one-eighth of the total expense. 
 
 The principal varieties of bricks are called malm, paviors, stocks, grizzles, places, and 
 shuffs. For the first and best kind, the clay was washed and selected with care ; 
 stocks were good enough for ordinary building purposes; the rest are inferior. The 
 difference in price between malms, paviors, and stocks, was 15s. or 20s. per 1000; be- 
 tween stocks and places, 10s. The average weight of a sand-stock brick is fully 5 
 pounds, that of a slop is 1 pound more. 
 
 I believe that the siliceous sand on the surface of the sand-stocks is useful in favour- 
 ing adhesion of mortar, by the production of a silicate of lime. To smooth aluminous 
 bricks, mortar sometimes forms no stony adhesion. 
 
 Mr. Prosser, of Birmingham, makes bricks by pressure. The clay is first ground 
 upon a slip kiln, as if for making pottery, then ground to a fine powder, and in that 
 dry state it is subjected to the heavy pressure of about 250 tons, in strong metal 
 moulds, by which means it is reduced to about one-third of its original thickness. 
 The clay seems to have retained sufficient moisture to give it cohesion, and the tiles 
 are perfectly sharp at the edges. They being then baked within seggars by the heat of 
 a kiln, seldom crack in the baking. The bricks thus formed are denser than usual, and 
 weigh 6f lbs., with a specific gravity of 2*5. 
 
 Fig. 14. represents Mr. Hunt's brick-making machine. The principal working 
 
 parts consist of 2 cylinders, each covered by an endless web, and so placed as to form 
 the front and back of a hopper, the two sides being iron plates, placed so that when 
 the hopper is filled with tempered clay from the pug-mill, the lower part of the 
 hopper, and consequently the mass of clay within it, has exactly the dimensions of 
 a brick. Beneath the hopper an endless chain traverses simultaneously with the 
 movement of the cylinders. The pallet-boards are laid at given intervals upon the 
 chain, and being thus placed under the hopper, while the clay is brought down with 
 a slight pressure, a frame with a wire stretched across it, is projected through the 
 mass of clay, cutting off exactly the thickness of the brick, which is removed at the 
 same moment by the forward movement of the endless chain. This operation is 
 repeated each time that a pallet-board comes under the hopper. 
 
 The chief object of this machine, which is worked by hand, is to produce good 
 square compact bricks of uniform quality, using only a slight pressure. It has been 
 found to be very difficult to dry bricks made by machinery, where a considerable pres- 
 sure has been employed, because, before the evaporation from the centre of the clay is 
 completed, the surfaces have become hard and peel off. The present machine is in 
 operation in several parts of England, producing usually about 1200 bricks per hour, 
 while each machine requires only 2 men and 3 boys to tend it, and to take off the 
 bricks. The clot-moulders are dispensed with, and the workmen are common 
 labourers, so that professed brick-makers at higher wages are not needed. 
 
 Fig. 15. shows Mr. Hunt's machine for making tiles, and it is on the same principle. 
 It consists of two iron cylinders, round which webs or bands of cloth revolve, whereby 
 
 G 
 
42 
 
 BRICKS. 
 
 the clay is pressed into a slab of uniform thickness, without adhering to the cylinders. 
 It is then carried over a covered wheel, curved on the rim, which gives the tile the 
 semi-cylindrical or other required form ; after which the tiles are polished and finished 
 
 by passing through three iron moulds of a horse-shoe form, as shown in the centre of 
 the cut, while they are at the same time moistened from a water cylinder placed above 
 them. The tiles are next cut off to such lengths as are wanted, and carried away by 
 an endless web, whence they are transferred by boys to the drying shelves. 
 
 Flat tiles, for sole pieces to draining tiles, are formed in nearly the same manner, 
 being divided into two portions while passing through the moulds ; the quantity of 
 clay used for one draining tile being as much as for two soles. 
 
 The method of making bricks in the vicinity of London differed from that of almost 
 all other places, because the material there employed is not pure clay, but a loam of 
 a slightly cohesive nature, which will not admit of its being used in the natural 
 state and burned in close kilns with coal ; but with an admixture of ashes it becomes 
 sufficiently tenacious to be formed into bricks, by inducing a slight semi-fusion. But 
 the coal-ashes are also of advantage in the process of burning, because they enable the 
 fire to spread gradually from the lower tiers, through the whole mass in the kiln or 
 clamp, and thus obviate the effect of an intense partial heat, where distinct coal fires 
 are trusted to alone, whereby the bricks nearest it get vitrified and glazed. 
 
 The brick kilns and clamps round London, and other large cities, which are fired 
 with the breeze-rubbish collected from dust holes, that contain the refuse of kitchens, 
 &c. emit, in consequence, most unpleasant effluvia; but brick-kilns fired with clean 
 coke or coals, give out no gases of a more noxious nature than common household fires. 
 The consideration of this subject was closely pressed upon my attention on being con- 
 sulted concerning an injunction issued by the Chancellor against a brick clamp in the 
 Isle of Wight, fired with clean coke cinders from the steam-engine furnace at Ports- 
 mouth Dock Yard. The bricks being of the description called sand-stock, were of 
 course made in moulds very slightly dusted with sand, to make them fall freely out. 
 The sand was brought from Portsmouth Harbour, and on being subjected to a degree 
 of heat, more intense certainly than it could suffer in the clamp, was discovered by two 
 chemical witnesses to give out traces of hydrochloric acid. Not content with this 
 trivial indication, the said chemists, in their evidence before the courts of law, paraded 
 a train of goblin gases, as the probable products of the pre-adjudicated clamp. 
 
 As it is well known to the chemist that common salt strongly ignited in contact with 
 moist sand will emit hydrochloric acid, there was nothing remarkable in the above 
 observation, but I ascertained that the sand with which the moulds were strewed would 
 give out no hydrochloric acid, at a heat equal at least to what the bricks were exposed 
 to in a clamp 10 or 12 feet high, and fired at its bottom only with a layer of cinders 
 3 or 4 inches thick. But I further demonstrated that the entire substance of the brick 
 with its scanty film of sand, on being exposed to ignition in a suitable apparatus, gave 
 out — not hydrochloric or any other corrosive acid, but ammonia gas. Hence, the 
 allegations that the clamp sent forth a host of acid gases to blight the neighbouring 
 trees, were shown to be utterly groundless ; on the contrary, the ammonia evolved from 
 the heated clay would act beneficially upon vegetation, while it was too small in quantity 
 to annoy any human being. A few yards to leeward of a similar clamp, in full activity, 
 I could perceive no offensive odour. All ferruginous clay, when exposed to the atmo- 
 sphere, absorbs ammonia from it, and of course emits it again on being gently ignited. 
 It is a reproach to science when, as in the above case, it lends itself to judicial 
 prejudice and oppression. 
 
BUTTER. 
 
 43 
 
 BRONZING {of Objects in Imitation of Metallic Bronze.) Plaster of Paris, paper, 
 wood, and pasteboard, may be made to resemble pretty closely the appearance of articles 
 of real bronze, modern or antique. The simplest way of giving a brilliant aspect of 
 this kind is with a varnish made of the waste gold leaf of the beater, ground up on a 
 porphyry slab with honey or gum- water. A coat of drying linseed-oil should be first 
 applied, and then the metallic powder is put on with a linen dossil. Mosaic gold 
 ground up with six parts of bone-ashes has been used in the same way. When it is 
 to be put on paper, it should be ground up alone with white of eggs or spirit varnish, 
 applied with a brush, and burnished when dry. When a plate of iron is plunged into 
 a hot solution of sulphate of copper, it throws down fine scales of copper, which being 
 repeatedly washed with water, and ground along with six times its weight of bone- 
 ashes, forms a tolerable bronzing. 
 
 Powdered and sifted tin may be mixed with a clear solution of isinglass, applied 
 with a brush, and burnished or not, according as a bright or dead surface is desired. 
 Gypsum casts are commonly bronzed by rubbing brilliant black-lead, graphite, upon 
 them with a cloth or brush. Real bronze long exposed to the air gets covered with a 
 thin film of carbonate of copper, called by virtuosi antique cerugo (patine antique, Fr. ) 
 This may be imitated in a certain degree by several applications skilfully made. The 
 new bronze being turned or filed into a bright surface, and rubbed over with dilute 
 aquafortis by a linen rag or brush, will become at first greyish, and afterwards take a 
 greenish blue tint ; or we may pass repeatedly over the surface a liquor composed of 
 1 part of sal ammoniac, 3 parts of carbonate of potash, and 6 of sea salt, dissolved in 
 1 2 parts of boiling water, to which 8 parts of nitrate of copper are to be added ; the 
 tint thereby produced is at first unequal and crude, but it becomes more uniform and 
 softer by time. A fine green-blue bronze may be obtained with very strong water of 
 ammonia alone, rubbing it at intervals several times upon the metal 
 
 The base of most of the secret compositions for giving the antique appearance is 
 vinegar with sal ammoniac. Skilful workmen use a solution of 2 ounces of that salt in 
 an English quart of French vinegar. Another compound which gives good results is 
 made with an ounce of sal ammoniac, and a quarter of an ounce of salt of sorrel (binox- 
 alate of potash), dissolved in vinegar. One eminent Parisian sculptor makes use of a mix- 
 ture of half an ounce of sal ammoniac, half an ounce of dommon salt, an ounce of spirits 
 of hartshorn, and an English quart of vinegar. A good result will also be obtained by 
 adding half an ounce of sal ammoniac, instead of the spirits of hartshorn. The piece 
 of metal being well cleaned, is to be rubbed with one of these solutions, and then dried 
 by friction with a fresh brush. If the hue be found too pale at the end of two or 
 three days, the operation may be repeated. It is found to be more advantageous to 
 operate in the sunshine than in the shade. 
 
 BUDE LIGHT. See Gas Light. 
 
 BUTTER is the fatty matter of milk, usually of that of the cow. Milk is com- 
 posed of butter, caseine, sugar of milk, several salts, and water. The butter exists in 
 the form of very small globules of nearly uniform size, quite transparent, and strongly 
 refractive of light. Milk left in repose throws up the lighter particles of butter to the 
 surface as cream. It was imagined that the butter was separated in the process of 
 churning, in consequence of the milk becoming sour ; but this is not the case, for milk 
 rendered alkaline by bi-carbonate of potash affords its butter fully more readily than 
 acidulous milk. The best temperature for churning milk or cream is 53° F. ; that of 
 60° is too high; and under 50 it is too low. By the churning action the heat rises from 
 3 to 4 degrees F. All the particles of butter are never separated by churning ; many 
 remain diffused through the butter-milk, and are easily discoverable by the microscope. 
 These are more numerous in proportion to the bulk of the liquid ; and hence it is more 
 economical to churn cream than the whole milk which affords it. It is computed that 
 a cow which gives 1 800 quarts (old English) of milk per annum, eats in that time 8000 
 lbs. of hay, and produces 140 lbs. of butter.* Analysis shows that this weight 
 of hay contains 168 pounds of fat. The finest flavoured butter is obtained from milk 
 churned not long after it is drawn ; but the largest proportion is derh/ed from the 
 cream thrown up by milk after standing 24 hours, in a temperature ©f about 50° F. 
 The butter-milk, which contains the very fermentable substance, caseine, should be well 
 separated from the butter by washing with cold water, and by beating with the hands, 
 or preferably, without water, for the sake of fine flavour, by the action of a press. 
 
 The French purify their butter by melting it in pots, plunged into water heated to 
 200° or 212° ; and sometimes they mix a pure brine with the melting butter, whereby 
 they favour the subsidence of the coagulated caseine and other impurities. The super- 
 natant clear butter should be drawn or poured off, and rapidly cooled, to prevent the 
 crystallization of its stearine and separation of its oleine, which injure its flavour and 
 appearance. 
 
 * Two pounds and a quarter of hay correspond to one quart of' good milk ; and a cow which eats 
 1 6,500 lbs. of hay will produce 300 lbs. of butter per annum. 
 
 G 2 
 
44 
 
 CALICO PRINTING. 
 
 c. 
 
 CALCIUM. The atomic weight of this element being an important point, both as 
 to pure chemistry and the chemical arts, has been the subject of innumerable researches. 
 Very lately Berzelius, in the Annalen der Chemie und Pkarmacie, XL VI. p. 241, has 
 collated the most recent results of the analysis of other philosophers with his own ; and 
 while Dumas, Marchand, and Erdmann estimate the weight at 20, that of hydrogen = 1, 
 or 250 oxygen = 100, he finds it ought to be, as compared with the latter, 251,9- and 
 to the former, 20,152. 
 
 CALICO PRINTING (4-colour machine). Of this beautiful and effective mecha- 
 nism an accurate section is exhibited at p. 220. of the Dictionary. The outside work- 
 ing gear is shown in Jiff. 16., where A, A is a part of the two strong iron frames or 
 
 cheeks in which the various rollers are mounted. They are bound together by the 
 rods and bolts a, a, a. B is the large iron pressure cylinder, which rests with its 
 gudgeons in bearings or bushes, which can be shifted up and down in slots of the side 
 cheeks A, A. These bushes are suspended from powerful screws, b, which turn in 
 brass nuts, made fast to the top of the frame A, as is plainly shown in the figure. 
 These screws serve to counteract the strong pressure applied beneath that cylinder by 
 the engraved cylinders D, E. 
 
 C, D, E, F, are four printing cylinders, named in the order of their operation. 
 They consist of strong tubes of copper or gun metal, forcibly thrust by a screw press 
 upon the iron mandrels, round which as shafts they revolve. The first and last cylin- 
 ders, C and F, are mounted in brass bearings, which may be shifted in horizontal slots 
 of the frame A. The pressure roller B, against whose surface they bear with a very 
 little obliquity downwards, may be nicely adjusted to that pressure by its elevating and 
 depressing screws. By this means C and F can be adjusted to B with geometrical 
 precision, and made to press it in truly opposite directions. 
 
CALICO PRINTING. 
 
 45 
 
 The bearings of the cylinders D and E are lodged also in slots of the frame A, 
 which point obliquely upwards towards the centre of B. The pressure of these two 
 print cylinders, C and F, is produced by two screws, c and d, which work in brass nuts 
 made fast to the frame, and very visible in the figure. The framework in which these 
 bearings and screws are placed has a curvilinear form, in order to permit the cylinders 
 to be readily removed and replaced, and also to introduce a certain degree of elasticity. 
 Hence the pressure applied to the cylinders C and F partakes of the nature of a spring, 
 a circumstance essential to their working smoothly, notwithstanding the occasional 
 inequalities in the thickness of the felt web and the calico. 
 
 The pressure upon the other two print cylinders, D and E, is produced by weights 
 acting with levers against the bearings. The bearings of D are, at each of their ends, 
 acted upon by cylindrical rods, which slide in long tubular bosses of the frame, and 
 press with their nuts g, at their under end upon the smaller arms of two strong levers 
 
 G, which lie on each side of the machine, and whose fulcrum is at h (in the lower 
 corner at the left hand). The longer arms of these levers, G, are loaded with weights, 
 
 H, whereby they are made to press up against the bearings of the roller D, with any 
 desired degree of force, by screwing up the nut g, and hanging on the requisite 
 weights. 
 
 The manner in which the cylinder E is pressed up against B is by a similar con- 
 struction to that just described. With each of its bearings there is connected, by 
 the link k, a curved lever, I, whose fulcrum or centre of motion is at o. By turning, 
 therefore, the screw m, the weight L, laid upon the end of the longer arm of the lever K 
 (of which there is one on each side of the machine), may be made to act or not at plea- 
 sure upon the bearings of the cylinder E. The operation of this exquisite machine 
 is minutely described in the Dictionary, pp. 220, 221. 
 
 A patent was obtained in August 1839, by Mr. J. C. Miller of Manchester, for cer- 
 tain improvements in printing calicoes, consisting of a modified mechanism, by which 
 the same effect can be produced as by block printing. 
 
 Figs. 17, 18, 19, are several views of this machine, calculated to print two pieces, or 
 two different patterns (on the same block) of calico, side by side, or four pieces, the 
 carriage printing both ways, the intended device consisting of four colours to be printed 
 from blocks. 
 
 Fig. 17. represents a side elevation, Jig. 18. a front view, and jig. 19. a trans- 
 verse section, taken nearly through the middle Of the machine. 
 
46 
 
 CALICO PRINTING. 
 
 The side or main framing is shown at a, a, supporting the colour boxes b, b, b, with 
 their doctors ; the furnishing tables or beds, c, c, c (substitutes for the sieves in ordinary 
 block printing) ; the printing table, d, d; and the feeding, drying, and colouring 
 rollers,/,/, g, g, h, h. 
 
 The machine is also provided with a carriage, i, i, for the printing blocks,^', j, j. 
 This carriage, i, i, travels in and out at suitable intervals, upon rails, k, k, attached to 
 the main framing. 
 
 The operation of the machine is effected by passing a driving strap, I, round the 
 driving pulley m, fixed at the extremity of the main driving shaft, n, n. At the other 
 end of this shaft, the bevil pinion, o, is keyed, gearing at suitable intervals with the bevil 
 wheel p, which is mounted upon the end of the cross shaft q ; at about the middle of 
 this shaft, the mitre wheels r, r, driving the upright shaft s, s, and mitre wheels, t, t, 
 above, actuate, by means of the spur pinions u, u, the feeding rollers / / and thus draw 
 the pieces of goods into the machine. 
 
 Simultaneously with the progress of the cloth, the mitre wheels v, v, at the other 
 end of the cross shaft q, drive the furnishing rollers w, w, w, by means of the spur gear- 
 ing x, x, x. The furnishing rollers, revolving in their respective colour-boxes, spread or 
 apply the colours upon the travelling endless blankets, y, y, y, which pass round the top 
 roller, and the furnishing tables or beds, c, c, c, in order to supply the colours to the 
 surfaces of the printing blocks, j, j, j. Either beds or the backs of the printing blocks 
 may be made slightly elastic, to insure the perfect taking up of the colours. 
 
 Supposing the carriage, i, i, to be run out upon its railways, at the farthest point from 
 the beds c, c, it is drawn inwards towards the furnishing beds c, c, by means of the 
 spur-wheel x, upon the driving-shaft n, taking into a small pinion, 1 (shown by dots 
 in fig. 17.), upon the shaft, 2. On the end of this shaft is also keyed the mangle 
 pinion, 3, gearing in the mangle wheel, 4, which is keyed upon the end of the shaft,°5. 
 This shaft drives the spur-wheel, 6, in gear with the pinion, 7, made fast to the shaft, s 
 (see fig. 19.). 
 
 Upon either end of the shaft, 5, is a rack pinion, 9, taking into the horizontal rack 10, 
 made fast to the carriage-frame, i, i ; and thus the blocks, j, j, are presented to the fur- 
 nishing blankets y, y, y, and take a supply of colour ready for printing. The travelling- 
 carriage and blocks now retire, by the agency of the mangle- wheel and pinion, 3 and 4, 
 
CALOMEL. 
 
 47 
 
 the pinion being fixed upon the end of the shaft, 2, and the wheel upon the other shaft 
 in a line with the shaft, 2. At this time another operation of the machine takes 
 place. 
 
 Upon the reverse end of the shaft, 5, is a pinion, 1 1, gearing with the spur-wheel, 12 ; 
 and by means of the spur gearing, 6 and 13, and counter-shaft, 14, the pinion, 15, drives 
 the spur-wheel, 16, which corresponds to the wheel, 12, on the other side of the machine. 
 To one of these spur-wheels are attached by bolts two quadrant levers, 17, 17 ; and as 
 these wheels revolve by means of the gearing just described, the levers, 17, 17, draw 
 down the chains, 18, 18, actuate the levers, 19 and 20, and thus elevate the whole series 
 of printing blocks in the parallel grooves, 21, 21 ; at the same time pressing or closing 
 them into one mass or block by expanding the springs 22, 22 ; and at the nest of the 
 carriage caused at a proper interval by the agency of the mangle-wheel, the blocks are 
 made to impress the patterns upon the surface of the goods at once, in four or more 
 different colours, and in one, two, or more widths of cloth at one operation. 
 
 The cloth is now drawn forward for the space of the exact width of one of the blocks, 
 or sketch of the design, by means of the spur-wheels and pinions, 23, 23, and passed 
 around heated cylinders, g, g, if necessary, and between the delivering rollers out of 
 the machine. These operations are to be repeated by the continuous rotation of the 
 main driving-shaft, until the printing is completed ; the colours making a single advance 
 upon the pattern at every presentation of the blocks, until the whole number of blocks 
 has been presented to the same space or portion of the goods successively. 
 
 The steam pipes, 24, are to be in connection with the printing table and drying 
 cylinders, in order to supply a degree of heat during the operation, which may be regu- 
 lated at pleasure. 
 
 To give suitable intervals of rest and motion to the various parts of the driving- 
 gear, an ordinary clutched box, 25 (shown in fig. 19.), and regulated by suitable stops 
 fixed to the travelling carriage, is used for throwing the wheel, p, in and out of gear with 
 the pinion, o ; this is to prevent clots of colour from being dragged upon the blocks or 
 cloth. — Newton's Journal, xxi. C. S. p. 242. 
 
 CALOMEL. A patent was obtained in September, 1841, by Anthony Todd 
 Thomson, M. D., for an improved method of manufacturing calomel and corrosive sub- 
 limate, as follows : — 
 
 This invention consists in combining chlorine in the state of gas with the vapour of 
 mercury or quicksilver, in order to produce calomel and corrosive sublimate. 
 
48 
 
 CALOTYPE. 
 
 The apparatus employed consists of a glass, earthenware, or other suitable vessel, 
 mounted in brick-work, and communicating at one end with a large air-tight chamber, 
 and at the other end, by means of a bent tube, with an alemhic, such as is generally 
 used for generating chlorine gas. The alembic is charged with a mixture of common 
 salt, binoxide of manganese and sulphuric acid, or of binoxide of manganese and mu- 
 riatic acid, in order to produce chlorine gas. 
 
 The mode of operating with this apparatus is as follows : — A quantity of mercury 
 or quicksilver is placed in the glass vessel, and the temperature of the same is raised to 
 between 350° and 660° Fahr., by means of an open fire beneath. The chlorine gas, as 
 it is generated, passes from the alembic through the bent tube into the glass vessel, and 
 there combining with the vapour of the mercury, forms either corrosive sublimate or 
 calomel, according to the quantity of chlorine gas employed. 
 
 The product is found at the bottom of the air-tight chamber, and may be removed 
 from the same through a door, when the operation is finished. 
 
 According to the patent of Mr. Josiah Jewel, the vapour of calomel was to be 
 transmitted into a vessel containing water, in order to condense it at. once into an 
 impalpable powder. But this process was beset with many difficulties. The vapour 
 of the calomel was afterwards introduced into a large receiver, into which steam 
 was simultaneously admitted ; but this plan has also been found to be precarious in the 
 execution. The best way is to sublime the calomel into a very large chamber from an 
 iron pot, in the same way as the flowers of sulphur are formed. The great body of 
 cool air serves to cause the precipitation of the calomel in a finely comminuted state. 
 It is afterwards washed with water, till it is no longer coloured by sulphuretted 
 hydrogen. 
 
 CALOTYPE is the name given by Mr. Fox Talbot to the art invented by him, of 
 making pictures on paper or other such surfaces by the agency of light. It is merely 
 an improved kind of photography. The process is as follows: — Dissolve 100 grains 
 of crystallised nitrate of silver in 6 ounces of distilled water, and brush over the paper 
 (Whatman's sized post answers well) with a soft brush on one side only, with this 
 solution, and mark the side. When nearly dry, dip it into a solution of iodide of 
 potassium (for only a few minutes), containing 500 grains of that salt dissolved in a 
 pint of water. As soon as the paper is completely imbued with this solution, it should 
 be immediately washed in distilled water, drained, and hung up to dry. This paper is 
 to be kept for subsequent use in a portfolio, and carefully secluded from light. 
 
 Next dissolve 100 grains of silver-nitrate in 2 ounces of distilled water, and add to 
 the solution one sixth of its volume of strong acetic acid. Keep this solution in the 
 dark. Make a saturated solution of gallic acid in distilled water. When it is re- 
 quired to make a calotype picture, the two liquids last described are to be mixed in 
 equal quantities, but only so much as is needed for the operation. With this gallo- 
 nitrate of silver, a sheet of the silver iodide paper is to be washed over upon its marked 
 side with a soft brush, an operation to be performed by candle-light. After half a 
 minute, the paper being dipped in water, and dried lightly by pressure between folds 
 of blotting paper, becomes so exceedingly sensitive to light, as to take a pictorial im- 
 pression in the camera in a space varying from one second to five minutes, according 
 to the brightness of illumination. The camera should be mounted with a meniscus 
 lens, in an adjustible tube, so as to throw the image of the object to be calotyped upon 
 a vertical plate of roughened glass, in the posterior side or wall of the wooden box. 
 Whenever the focus is correctly adjusted, the glass is withdrawn, and replaced by 
 sliding in a groove a frame with the prepared sheet of paper fixed flat upon it, the pre- 
 pared side towards the lens, but screened from light by a card or thin board. The 
 screen being now removed, the light acts upon the paper, and produces a picture. A 
 camera made entirely of metal, in a conical form, and mounted on a stand like a 
 telescope, which has been invented for calotype purposes, by Dr. Petzval and M. 
 Voigtlander, of Vienna, is recommended in preference to all others, by Mr. Talbot, 
 especially for taking portraits. 
 
 The paper, after exposure for the due time in the camera, is to be again covered 
 from the light, taken out, and subjected to another process ; for as yet it has no 
 pictorial appearance. To bring out this effect, it must be washed with the gallo- 
 nitrate of silver, and then be gently warmed. In a few seconds the portions of the 
 paper upon which the light has acted will begin to darken, and eventually grow quite 
 black, while the rest of the paper retains its original hue. Even though the pictorial 
 impression be very faint, it may be brought out by a second application of the same 
 solution. The operator should watch the gradual development of the tints ; and when 
 it is sufficient, he should fix them by dipping the paper in water, drying it slightly 
 with blotting paper, then washing it over with a solution of bromide of potassium, 
 containing 100 grains of that salt, dissolved in 8 or 10 ounces of water. Strong brine 
 will also answer, but not so well. Similar calotype pictures may be made by using 
 
CANDLES. » 49 
 
 the bright light emitted from lime ignited by the oxy-hydrogcn flame ; as is practised 
 in making the Daguerrotype portraits at night. 
 
 In all the photographic pictures the lights and shades of the object are reversed ; 
 but they may be made conformable to nature by rendering the paper transparent with 
 white wax scraped upon its back, melting this in by rubbing it with a hot smoothing- 
 iron, after it is placed between two sheets of common paper, then laying it upon paper 
 imbued with bromide of potassium, and exposing it to sunshine. Portraits are best 
 taken by means of a lens, whose focal length is 3 or 4 times only greater than the 
 diameter of the aperture. 
 
 CANDLES. Messrs. Ilempel and Blundell have given a very minute account of 
 the process for making palm-oil, stearic and margaric acids, in the specification of 
 their patent for this mode of manufacturing candles : — 
 
 1. Their first process is called crystallisation, which consists in pouring the melted 
 palm-oil into iron pans, and allowing it to cool slowly, whereby, at about 75° F., the 
 elaine separates from the crystalline stearine and margarine. 
 
 2. The concreted oil is subjected to the action of an hydraulic press, in order to sepa- 
 rate the elaine from the solid fats. 
 
 3. This process is called oxidation. To 104 lbs. of the stearine and margarine, 
 melted in an iron pan, about 12 lbs. of slaked and sifted quicklime are added, with 
 diligent stirring, during which the temperature is to be slowly raised to 240° R, and 
 so maintained for about 3 hours, till a perfect chemical combination takes place. This 
 is shown by the mass becoming thin, transparent, and assuming a glassy appearance 
 when it cools. The fire being now withdrawn, cold water is added very gradually at 
 first, with brisk stirring till the whole mass falls into a state of powdery granulation, 
 when it is passed through a wire sieve to break down any lumps that may remain. 
 
 4. Separation of the stearic and margaric acids from the lime. For this purpose, as 
 much muriate of lime (chlorcalcium) is taken as will, with its equivalent quantity of 
 sulphuric acid (8 lbs. of dry chlorcalcium require 7 lbs. of the strongest sulphuric 
 acid), produce as much muriatic acid as will dissolve the lime combined with the fat 
 acids ; and therefore that quantity of muriate of lime dissolved in water must be 
 treated with as much sulphuric acid as will saturate its lime and throw it down in the 
 state of sulphate of lime. Add the supernatant solution of muriatic acid in such pro- 
 portion to the stearate and margarate of lime as will rather more than saturate the 
 lime. Three pounds of muriatic acid diluted with 9 lbs. of water are stated as enough 
 for 1 lb. of lime. This mixture is to be let alone for 3 or 4 days, in order to insure the 
 complete separation of the lime from the fat acids ; and then the mixture is heated so 
 as to melt and cause them to separate in a stratum on the top of the liquid. The re- 
 sulting muriate of lime is drawn off into another tub, and decomposed by its dose of 
 sulphuric acid, so as to liberate its muriatic acid for a fresh operation. 
 
 5. The fat acids, being well washed by agitation with hot water, are then set to cool 
 and crystallise, in which state they are subjected to the action of the hydraulic press, 
 at a temperature of 75° F., whereat the margaric acid runs off from the solid stearic 
 acid. 
 
 6. Bleaching. The stearic acid is taken from the press, and exposed upon water in 
 large shallow vessels placed in the open air, where it is kept at the melting tempera- 
 ture from 8 to 12 hours, stirring meanwhile, in order to promote the blanching action 
 of the atmosphere. The margaric acid is bleached in a similar manner in separate 
 vessels. 
 
 7. Refining process. The fat is warmed again, and poured in a liquid state into an 
 agitating tub ; where, for every 1000 lbs. of the stearic acid, about 2i lbs. of common 
 black oxide of manganese, and 40 lbs. of concentrated sulphuric acid, diluted with 
 200 lbs. of pure water, are to be used. This solution (" mixture"), Avhile warm from 
 the heat evolved in diluting the acid, is placed in a suitable vessel above the agitating 
 tub. The stearic acid being at the melting point, in the vessel below, agitation is to 
 be given with a revolving shaft, while the mixed manganese and acid are run slowly 
 down into it, till the whole be well mixed, which generally requires about 2 hours. 
 The mass is allowed to lie in this state for 48 hours ; after which it may be boiled by 
 steam for 2 or 3 hours, when it will be sufficiently refined. The sulphuric acid, which 
 is at the bottom, is now run off, and the stearic acid which remains is well washed with 
 pure water. It is then put into large conical vessels of stone-ware, inclosed in a box 
 or jacket, kept warm by steam-heat, and lined with conical bags of suitable strong 
 filtering paper, through which, being warm, it finds its way ; and when the stearic acid 
 has been thus filtered, it is run into blocks, when it will be found to be a beautiful 
 stearic acid or palm- wax, and is ready to be made into candles in the usual way. 
 
 On the above process with manganese and diluted sulphuric acid, it may be observed, 
 that no solution or chemical action takes place between them, and their joint use seems 
 therefore most problematical. The patentees proceed to describe other processes of 
 
 H 
 
50 
 
 CAOUTCHOUC. 
 
 refining, in which sulphate of manganese, with common salt, phosphoric acid (highly 
 concentrated), and oxalic acid, are used, and in my opinion either ignorantly or for the 
 purpose of mystification ; for, as prescribed, they can serve no possible purpose of 
 purifying the stearine. 
 
 The chief solid constituent of palm-oil is margaric acid. This they direct to be 
 melted with tallow, in the proportion of from 10 to 20 lbs. of the former to 100 lbs. of 
 the latter. See Newton's Journal, C. S., xi. 207. 
 
 I was told by M. Runge, at Berlin, that he was the inventor of the process for 
 making white margaric acid from palm-oil, and that Hempel had got it somehow 
 from him, but most imperfectly, as it would appear. Hempel died here in the midst 
 of the above patent operations ; but the specification is, no doubt, a specimen of his 
 manufacture of Runge's margaric acid. He gave me a splendid pearly-looking sample. 
 
 CAOUTCHOUC. Hitherto the greater part of the caoutchouc has been imported 
 into Europe from South America, and the best from Para ; but of late years a con- 
 siderable quantity has been brought from Java, Penang, Sincapore, and Assam. About 
 three years ago, Mr. William Griffith published an interesting report upon the 
 Ficus elastica, the caoutchouc tree of Assam, which he drew up at the request of Captain 
 Jenkins, agent in that country to the Governor- General of India. This remarkable 
 species of figtree is either solitary, or in twofold or threefold groups. It is larger and 
 more umbrageous than any of the other trees in the extensive forest where it abounds, 
 and may be distinguished from the other trees, at a distance of several miles, by 
 the picturesque appearance produced by its dense, huge, and lofty crown. The main 
 trunk of one was carefully measured, and was found to have a circumference of no less 
 than 74 feet ; while the girth of the main trunk along with the supports immediately 
 round it, was 120 feet. The area covered by the expanded branches had a circum- 
 ference of 610 feet. The height of the central tree was 100 feet. 
 
 It has been estimated, after an accurate survey, that there are 43,240 such noble 
 trees within a length of 30 miles, and breadth of 8 miles of forest near Ferazepoor, in 
 the district of Chardwar, in Assam. 
 
 Lieutenant Veitch has since discovered that the Ficus elastica is equally abundant in 
 the district of Naudwar. Its geographical range in Assam seems to be between 25 
 deg. 10 min. and 27 deg. 20 min. of north latitude, and between 90 deg. 40 min. and 
 95 deg. 30 min. of east longitude. It occurs on the slopes of the hills, up to an eleva- 
 tion of probably 22,500 feet. This tree is of the banyan tribe, famed for " its pillared 
 shade, where daughters grow about the mother tree," which has furnished the motto 
 tot rami, quot arbores, to the Royal Asiatic Society. Species of this genus afford grate- 
 ful shade, however, in the tropical regions of America, as well as Asia. 
 
 Many species of other trees yield a milky tenacious juice, of which birdlime has been 
 frequently made ; as Artocarpus integrifolia, and Lakoocha, Ficus indica and religiosa, 
 also F. Tsiela, Boxburghii, glomerata, and oppositifolia. From some of these an inferior 
 kind of caoutchouc has been obtained. 
 
 The juice of the Ficus elastica of Chardwar is better when drawn from the old than 
 from the young trees, and richer in the cold season than in the hot. It is extracted by 
 making incisions a foot apart, across the bark down to the wood, all round the trunk, 
 and also the large branches, up to the very top of the tree ; the quantity which exudes 
 increasing with the height of the incision. The bleeding may be safely repeated once 
 every fortnight. The fluid, as fresh drawn, is nearly of the consistence of cream, and 
 pure white. Somewhat more than half a maund (42 lbs.) is reckoned to be the average 
 produce of each bleeding of one tree; or 20,000 trees will yield about 12,000 maunds 
 of juice; which is composed in 10 parts, of from 4 to 6 parts of water, and, of course, 
 from 6 to 4 parts of caoutchouc. The bleeding should be confined to the cold months, 
 so as not to interfere with, or obstruct the vigorous vegetation of the tree in the hot 
 months. 
 
 Mr. Griffith says, that the richest juice is obtained from transverse incisions made 
 into the wood of the larger reflex roots, which are half exposed above ground, and that 
 it proceeds from the bark alone. Beneath the line of incision, the natives of Assam 
 scoop out a hole in the earth, in which they place a leaf of the Phrynium capitatum, 
 Lin., rudely folded up into the shape of a cup. He observes that the various species 
 of Tetranthera, upon which the Moonga silkworm feeds, as also the castor oil plant, 
 which is the chief food of the Eria silkworm, do not afford a milky caoutchouc juice. 
 Hence it would appear that Dr. Royle's notion of caoutchouc forming a necessary 
 ingredient in the food of silkworms, and being " in some way employed in giving 
 tenacity to their silk," seems to be unfounded. If Botany discountenances this idea, 
 Chemistry would seem to scout it altogether ; for silk contains 1 1 -33 per cent, of azote, 
 and caoutchouc contains none at all ; being simply a solid hydro-carburet, and, there- 
 fore, widely dissimilar in constitution to silk, which consists of oxygen 34*04, azote 
 11-33, carbon 50*69, and hydrogen 3*94 in 100 parts. 
 
CAOUTCHOUC. 
 
 51 
 
 This hydro-carburet emulsion is of common occurrence in the orders Euphorbiacia 
 and Tulicea, which may be looked on as the main sources of caoutchouc. The Ame- 
 rican caoutchouc is said to be furnished by the Siphonia elastica, or the Hevea guia- 
 nensis of Aublet, a tree which grows in Brazil, and also in Surinam. 
 
 Dr. Royle sent models of cylinders, of 1' to 2i inches in diameter, and 4 or 5 inches 
 in length, to both the Asiatic and Agricultural Societies of Bengal, to serve as patterns 
 for the natives to mould their caoutchouc by. Mr. Griffith says that this plan of 
 forming the caoutchouc into tumblers or bottles, as recommended by the committee of 
 the London Joint-stock Caoutchouc Company, is, in his opinion, the worst that can 
 possibly be offered ; being tedious, laborious, causing the caoutchouc to be blackened 
 in the drying, and not obviating the viscidity of the juice when it is exposed to the 
 sun. He recommends, as a far better mode of treating the juice, to work it up with 
 the hands, to blanch it in water, and then subject it to pressure. I shall presently 
 describe a still better method which has recently occurred to me, in experimenting 
 upon the caoutchouc juice. This fluid, with certain precautions, chiefly exclusion 
 from air and much warmth, may be kept in the state of a creamy emulsion for a very 
 long time. 
 
 NEW EXPERIMENTAL RESEARCHES ON CAOUTCHOUC. 
 
 The specific gravity of the best compact Para caoutchouc, 
 
 taken in dilute alcohol, is - - - 0*941567 
 
 The specific gravity of the best Assam is - - - 0*942972 
 
 „ „ Sincapore - - - 0-936650 
 
 Penang - - - 0-919178 
 
 Having been favoured by Mr. Sievier, formerly managing director of the Joint-stock 
 Caoutchouc Company, and by Mr. Beale, engineer, with two different samples of caout- 
 chouc juice, I have subjected each to ehemieal examination. 
 
 That of Mr. Sievier is greyish brown, that of Mr. Beale is of a milky grey colour ; 
 the deviation from whiteness in each case being due to the presence of aloetic matter, 
 which accompanies the caoutchouc in the secretion by the tree. The former juice is of 
 the consistence of thin cream, has a specific gravity of 1 -04125, and yields, by exposure 
 upon a porcelain capsule, in a thin layer, for a few days, or by boiling, for a few mi- 
 nutes, with a little water, 20 per cent of solid caoutchouc. The latter, though it has the 
 consistence of pretty rich cream, has a specific gravity of only 1-0175. It yields no 
 less than 37 per cent, of white, solid, and very elastic caoutchouc. 
 
 It is interesting to observe how readily and compactly the separate little cloths or 
 threads of caoutchouc coalesce into one spongy mass in the progress of the ebullition, 
 particularly if the emulsive mixture be stirred ; but the addition of water is necessary 
 to prevent the coagulated caoutchouc from sticking to the sides or bottom of the vessel 
 and becoming burnt. In order to convert the spongy mass thus formed into good 
 caoutchouc, nothing more is requisite than to expose it to moderate pressure between 
 the folds of a towel. By this process the whole of the aloetic extract, and other vege- 
 table matters, which concrete into the substance of the balls and junks of caoutchouc 
 prepared in Assam and Java, and contaminate it, are entirely separated, and an article 
 nearly white and inodorous is obtained. Some of the cakes of American caoutchouc 
 exhale when cut the fcetor of rotten cheese ; a smell which adheres to the threads made 
 of it. after every process of purification. 
 
 In the interior of many of the balls which come from both the Brazils and East In- 
 dies, spots are frequently found of a viscid tarry-looking matter, which, when exposed 
 to the air, act in some manner as a ferment, and decompose the whole mass into a soft 
 substance, which is good for nothing. Were the plan of boiling the fresh juice along 
 with its own bulk of water, or a little more, adopted, a much purer article would be 
 obtained, and with incomparably less trouble and delay, than has been hitherto brought 
 into the market. 
 
 I find that neither of the above two samples of caoutchouc juice affords any appear- 
 ance of coagulum when mixed in any proportions with alcohol of 0-825 specific gravity; 
 and, therefore, I infer that albumen is not a necessary constituent of the juice, as Mr. 
 Faraday inferred from his experiments published in the 21st vol. of the Journal of the 
 Royal Institution. 
 
 The odour of Mr. Sievier's sample is slightly aeescent, that of Mr. Beale's, which is 
 by far the richer and purer, has no disagreeable smell whatever. The taste of the 
 latter is at first bland and very slight, but eventually very bitter, from the aloetic im- 
 pression upon the tongue. The taste of the former is bitter, from the first, in conse- 
 quence of the great excess of aloes which it contains. When the brown solution which 
 remains in the capsule, after the caoutchouc has been separated in a spongy state by 
 ebullition, from 100 grains of the richer juice is passed through a filter and evaporated,, 
 it leaves 4 grains of concrete aloes. 
 
 H 2 
 
52 
 
 CAOUTCHOUC. 
 
 Both of these emulsive juices mix readily with water, alcohol, and pyroxilic spirit, 
 though they do not become at all clearer ; they will not mix with caoutchoucine (the 
 distilled spirit of caoutchouc), or with petroleum-naphtha, but remain at the bottom of 
 these liquids as distinct as mercury does from water. Soda caustic lye does not dis- 
 solve the juice ; nitric acid (double aquafortis) converts it into a red curdy magma. 
 The filtered aloetic liquid is not affected by the nitrates of baryta and silver ; it affords 
 with oxalate of ammonia minute traces of lime. 
 
 J. CAOUTCHOUC MANUFACTURE. 
 
 This department of operative industry has, within a few years, acquired an importance 
 equal to that of some of the older arts, and promises, ere long, to rival even the ancient 
 textile fabrics in the variety of its designs and applications. The manufacture of 
 caoutchouc has, at present, three principal branches : — 1. The condensation of the crude 
 lumps or shreds of caoutchouc, as imported from South America, India, &c, into com- 
 pact homogeneous blocks, and the cutting of these blocks into cakes or sheets for the 
 stationer, surgeon, shoemaker, &c. 2. The filature of either the Indian rubber bottles, 
 or the artificial sheet caoutchouc, into tapes and threads of any requisite length and 
 fineness, which, being clothed with silk, cotton, linen, or woollen yarns, form the basis 
 of elastic tissues of every kind. 3. The conversion of the refuse cuttings and coarser 
 qualities of caoutchouc into a viscid varnish, which, being applied between two sur- 
 faces of cloth, constitutes the well-known double fabrics, impervious to water and air. 
 
 I. The caoutchouc, as imported in skinny shreds, fibrous balls, twisted concretions, 
 cheese-like cakes, and irregular masses, is, more or less, impure, and sometimes fraudu- 
 lently interstratified with earthy matter. It is cleansed by being cut into small pieces, 
 and washed in warm water. It is now dried on iron trays, heated with steam, while being 
 carefully stirred about to separate any remaining dirt, and is then passed through, be- 
 tween a pair of iron rolls, under a stream of water, whereby it gets a second washing, 
 and becomes at the same time equalized by the separate pieces being blended together. 
 The shreds and cuttings thus laminated, if still foul or heterogeneous, are thrown back 
 into a kind of hopper over the rolls, set one-sixteenth of an inch apart, and passed se- 
 veral times through between them. The above method of preparation is that practised 
 by Messrs. Keene and Co., of Lambeth, in their excellent manufactory, under a patent 
 granted in October, 1836, to Mr. Christopher Nickels, a partner in the firm. 
 
 In the great establishment of the Joint- Stock Caoutchouc Company, at Tottenham, 
 originally under the direction of Mr. Sievier, a gentleman distinguished no less by his 
 genius and taste as a sculptor, than by his constructive talents, the preparatory rinsing 
 and lamination are superseded by a process of washing practised in Mr. Nickels's second 
 operation, commonly called the grinding, or, as it should more properly be styled, the 
 kneading. The mill employed for agglutinating or incorporating the separate fragments 
 and shreds of caoutchouc into a homogeneous elastic ball, is a cylindrical box or drum 
 of cast iron, 8 or 9 inches in diameter, set on its side, and traversed in the line of its 
 horizontal axis (also 8 or 9 inches long) by a shaft of wrought iron, furnished with 3 
 rows of projecting bars, or kneading arms, placed at angles of 120 dcg. to each other. 
 These act by rotation against 5 chisel-shaped teeth, which stand obliquely up from the 
 front part of the bottom of the drum. The drum itself consists of 2 semi-cylinders ; 
 the under of which is made fast to a strong iron framing, and the upper is hinged to the 
 under one behind, but bolted to it before, so as to form a cover or lid, which may be 
 opened or laid back at pleasure, in order to examine the caoutchouc from time to time, 
 and take it out when fully kneaded In the centre of the lid a funnel is made fast, by 
 which the cuttings and shreds of the Indian rubber are introduced, and a stream of 
 water is made to trickle in, for washing away the foul matter often imbedded in it. 
 The power required to turn the axis of one of these mills, as the drums or boxes are 
 called, may be judged of from the fact, that if it be only 2 inches in diameter, it is 
 readily twisted asunder, and requires to be 3 inches to withstand every strain produced 
 by the fixed teeth holding "the caoutchouc against the revolving arms. Five pounds 
 constitute a charge of the material. 
 
 One of the most remarkable phenomena of the kneading operation, is the prodigious 
 heat disengaged in the alternate condensation and expansion of the caoutchouc. Though 
 the water be cold as it trickles in, it soon becomes boiling hot, and emits copious va- 
 pours. When no water is admitted, the temperature rises much higher, so that the 
 elastic lump, though a bad conductor of heat, cannot be safely touched with the hand. 
 As we shall presently find that caoutchouc suffers no considerable or permanent dimi- 
 nution of its volume by the greatest pressure which can be applied, we must ascribe- 
 the heat evolved in the kneading process to the violent intestine movements excited 
 throughout all the particles of the elastic mass. 
 
 During the steaming, much muddy water runs off through apertures in the bottom 
 of the drum. In the course of half an hour's trituration, the various pieces become 
 
CAOUTCHOUC. 
 
 51 
 
 agglutinated into a soft, elastic, ovoid ball, of a reddish brown colour. This ball is 
 now transferred into another similar iron drum, where it is exposed to the pricking and 
 kneading action of 3 sets of chisel points, 5 in each set, that project from the revolving 
 shaft at angles of 120 deg. to each other, and which encovinter the resistance occasioned 
 by five stationary chisel teeth, standing obliquely upwards from the bottom of the 
 drum. Here the caoutchouc is kneaded dry along with a little quicklime. It soon 
 gets very hot ; discharges in steam through the punctures, the water and air which it 
 had imbibed in the preceding washing operation ; becomes, in consequence, more com- 
 pact ; and, in about an hour, assumes the dark brown colour of stationers' rubber. 
 During all this time frequent explosions take place, from the expansion and sudden 
 extrication of the imprisoned air and steam. 
 
 From the second set of drums the ball is transferred into a third set, whose revolving 
 shaft, being furnished both with flat pressing bars, and parallel sharp chisels, perpen- 
 dicular to it, exercises the twofold operation of pricking and kneading the mass, so -as 
 to condense the caoutchouc into a homogeneous solid. Seven of these finished balls, 
 weighing, as above stated, 5 pounds each, are then introduced into a much larger iron 
 drum of similar construction, but of much greater strength, whose shaft is studded all 
 round with a formidable array of blunt chisels. Here the separate balls become per- 
 fectly incorporated into one mass, free from honeycomb cells or pores, and therefore fit 
 for being squeezed into a rectangular or cylindrical form in a suitable cast-iron mould, 
 by the action of a screw-press. When condensed to the utmost in this box, the lid is 
 secured in its place by screw bolts, and the mould is set aside for several days. It is a 
 curious fact, that Mr. Sievier has tried to give this moulding force, by the hydraulic 
 press, without effect, as ihe cake of caoutchouc, after being so condensed, resiles much 
 more considerably than after the compressing action of the screw. The cake form 
 generally preferred for the recomposed, ground, or milled caoutchouc, is a rectangular 
 mass, about 1 8 inches long, 9 inches broad, and 5 inches thick. 
 
 This is sliced into cakes for the stationer, and into sheets for making tapes and threads 
 of caoutchouc, by an ingenious self-acting machine, in which a straight steel blade, with 
 its edge slanting downwards, is made to vibrate most rapidly to and fro in a horizontal 
 plane ; while the cake of caoutchouc, clamped or embraced at each side between two 
 strong iron bars, is slowly advanced against the blade by screw- work, like that of the 
 slide rest of a lathe. In cutting caoutchouc by knives of every form, it is essential that 
 either the blade or the incision be constantly moistened with water ; for otherwise the 
 tool would immediately stick fast. As the above straight vibrating knife slants ob- 
 liquely downwards, the sheet which it cuts off spontaneously turns up over the blade in 
 proportion as it is detached from the bottom mass of the cake. The thicker slices are 
 afterwards cut by hand, with a wetted knife, into small parallelopipeds for the stationer, 
 the sections being guided rectangularly by saw lines in a wooden frame. The whole- 
 sale price of these is now reduced to 2s. per pound. Slices may be cut off to almost 
 any desired degree of thinness, by means of an adjusting screw — a mechanism that acts 
 against a board which supports the bottom of the cake, and raises it by any aliquot part 
 of an inch, the cutting blade being caused to vibrate always in the same horizontal 
 plane. These thin slices constitute what is called sheet caoutchouc, and they serve tole- 
 rably for making tubes for pneumatic apparatus, and sheaths of every kind ; since, if 
 their two edges be cut obliquely with clean scissors, they may be made to coalesce, by 
 gentle pressure, so intimately, that the line of junction cannot be discovered either by 
 the eye, or by inflation of a bag or tube thus formed. 
 
 The mode of recomposing the cuttings, shreds, and coarse lumps of caoutchouc into 
 a homogeneous elastic cake, specified by Mr. Nickels, for his patent, sealed October 24, 
 1 836, is not essentially different from that above described. The cylinders of his mill 
 are more capacious, are open at the sides like a cage, and do not require the washing 
 apparatus, as the caoutchouc has been cleansed by previous lamination and rinsing. 
 He completes the kneading operation, in this open cylinder, within the space of about 
 two hours, and afterwards squeezes the large ball so formed into the cheese form, in a 
 mould subjected to the action of an hydraulic press. As he succeeds perfectly in making 
 compact cakes in this way, his caoutchouc must differ somewhat in its physical consti- 
 tution from that recomposed by Mr. Sievier's process. He uses a press of the power 
 of 70 tons ; such pressure, however, must not be applied suddenly, but progressively, 
 at intervals of two or three minutes between each stroke ; and when the pressing is 
 complete, he suffers the caoutchouc to remain under pressure till it is cold, when he 
 thrusts it out of the mould entirely, or, placing his mould in the slide-rest mechanism, 
 he gradually raises the caoutchouc out of it, while the vibrating knife cuts it into slices 
 in the manner already described. The elegant machine by which these sheets are now 
 so easily and accurately sliced, was, I believe, originally contrived and constructed by 
 Mr. Beale, engineer, Church-lane, Whitechapel. 
 
54 
 
 CAOUTCHOUC. 
 
 IX. FILATURE OF CAOUTCHOUC FOR MAKING ELASTIC FABRICS. 
 
 Messrs. Rattier and Guibal mounted in their factory at St. Denys, so long ago as the 
 year 1826 or 182'7, a machine for cutting a disk of caoutchouc into a continuous fillet 
 spirally, from its circumference towards its centre. This flat disc was made by pressing 
 the bottom part of a bottle of Indian rubber in an iron mould. I have described 
 this machine under the article Elastic Bands, in the Dictionary. A machine 
 on the same principle was made the subject of a patent by Mr. Joshua Proctor 
 Westhead, of Manchester, in Feb. 16. 1836 ; and, being constructed with the well-known 
 precision of Manchester workmanship, it has been found to act perfectly well in cutting 
 a disc of caoutchouc, from the circumference towards the centre spirally, into one con- 
 tinuous length of tape. For the service of this machine, the bottom of a bottle of India 
 rubber of good quality being selected, is cut off and flattened by heat and pressure into 
 a nearly round cake of uniform thickness. This cake is made fast at its centre by a 
 screw nut and washer to the end of a horizontal shaft, which may be made to revolve with 
 any desired velocity by means of appropriate pulleys and bands, at the same time that 
 the edge of the disc of caoutchouc is acted on by a circular knife of cast steel, made to 
 revolve 3000 times per minute, in a plane at right angles to that of the disc, and to 
 advance upon its axis progressively, so as to pare off a continuous uniform tape or fillet 
 from the circumference of the cake. During this cutting operation, the knife and 
 caoutchouc are kept constantly moist with a slender stream of water. A succession of 
 threads of any desired fineness is afterwards cut out of this fillet, by drawing it in a 
 moist state through a guide slit, against the sharp edge of a revolving steel disc. This 
 operation is dexterously performed by the hands of young girls. MM. Rattier and 
 Guibal employed, at the above-mentioned period, a mechanism consisting of a series of 
 circular steel knives, fixed parallel to each other at minute distances, regulated by in- 
 terposed washers upon a revolving shaft ; which series of knives acted against another 
 similar series, placed upon a parallel adjoining shaft, with the effect of cutting the tape 
 throughout its length into eight or more threads at once. An improved modification 
 of that apparatus is described and figured in the specification of Mr. Nickels's patent of 
 October, 1836. He employs it for cutting into threads the tapes made from therecom- 
 posed caoutchouc. 
 
 The body of the bottle of India rubber, and in general any hollow cylinder of caout- 
 chouc, is cut into tapes, by being first forced upon a mandril of soft wood of such 
 dimensions as to keep it equally distended. This mandril is then secured to the shaft 
 of a lathe, which has one end formed into a fine-threaded screw, that works in a fixed 
 nut, so as to traverse from right to left by its rotation. A circular disc of steel, kept 
 moist, revolves upon a shaft parallel to the preceding, at such a distance from it as to 
 cut through the caoutchouc, so that, by the traverse movement of the mandril shaft, the 
 hollow cylinder is cut spirally into a continuous fillet of a breadth equal to the thickness 
 of the side of the cylinder. Mr. Nickels has described two methods of forming hollow 
 cylinders of recomposed caoutchouc, for the purpose of being cut into fillets by such a 
 machine. 
 
 It is probable that the threads formed from the best India rubber bottles, as imported 
 from Para, are considerably stronger than those made from recomposed caoutchouc, 
 and therefore much better adapted for making Mr. Sievier's patent elastic cordage. 
 When, however, the kneading operation has been skilfully performed, I rind that the 
 threads of the ground caoutchouc, as it is incorrectly called by the workmen, answer 
 well for every ordinary purpose of elastic fabrics, and are, of course, greatly more 
 economical, from the much lower price of the material. 
 
 Threads of caoutchouc are readily pieced by paring the broken ends obliquely with 
 scissors, and then pressing them together with clean fingers, taking care to admit no 
 grease or moisture within the junction line. These threads must be deprived of their 
 elasticity before they can be made subservient to any torsile or textile manufacture. 
 Each thread is inelasticated individually in the act of reeling, by the tenter boy or girl 
 pressing it between his moist thumb and finger, so as to stretch it to at least eight times 
 its natural length, while it is drawn rapidly through between them by the rotation of 
 the power-driven reel. This extension is accompanied with condensation of the caout- 
 chouc, and with very considerable disengagement of heat, as pointed out in Nichol- 
 son's Journal upwards of 30 years ago, by Mr. Gough, the blind philosopher of 
 Kendal. I attempted to stretch the thread, in the act of reeling, but found the 
 sensation of heat too painful for my unseasoned fingers. The reels, after being com- 
 pletely filled with the thread, are laid aside for some days, more or fewer, according 
 to the quality of the caoutchouc, the recomposed requiring a longer period than the 
 bottle material. When thus rendered inelastic, it is wound off upon bobbins of 
 various sizes, adapted to various sizes of braiding, or other machines, where it is to be 
 clothed with cotton or other yarn. 
 
CAOUTCHOUC 
 
 55 
 
 In the process of making the elastic tissues, the threads of caoutchouc being first of 
 all deprived of their elasticity, are prepared for receiving a sheath upon the braiding 
 machine. For this purpose they are stretched by hand, in the act of winding upon the 
 reel, to 7 or 8 times their natural length, and left two or three weeks in that state of 
 tension upon the reels. Thread thus inelasticated has a specific gravity of no less than 
 0-948732 ; but when it has its elasticity restored, and its length reduced to its pristine 
 state, by rubbing between the warm palms of the hands, the specific gravity of the 
 same piece of thread is reduced to 0*925939. This phenomenon is akin to that exhi- 
 bited in the process of wire-drawing, where the iron or brass gets condensed, hard, and 
 brittle, while it disengages much heat : which the caoutchouc thread also does in a 
 degree intolerable to unpractised fingers, as above mentioned. 
 
 The thread of the Joint- Stock Caoutchouc Company is numbered from 1 to 8. 
 No. 1. is the finest, and has about 5000 yards in a pound weight ; No. 4. has 2000 in 
 the pound weight ; and No. 8. 700, being a very powerful thread. The finest is used 
 for the finer elastic tissues, as for ladies' silver and gold elastic bracelets and bands. 
 The ropes made by Mr. Sievier with the strongest of the above threads, clothed with 
 hemp and worked in his gigantic braiding machine, possess, after they are re-elasticated 
 by heat, an extraordinary strength and elasticity; and, from the nearly rectilinear direc- 
 tion of all the strands, can stand, it is said, double the strain of the best patent cordage 
 of like diameter. 
 
 In treating of the manufacture of elastic fabrics, I nave great pleasure in adverting 
 to the ribbon looms at Holloway, which display to great advantage the mechanical 
 genius of the patentee, Mr. Sievier. Their productive powers may be inferred from 
 the following statement : — 5000 yards of 1 -inch braces are woven weekly in one 18 
 ribbon loom, whereby the female opei-ative, who has nothing to do but watch its auto- 
 matic movements, earns 10s. a-week ; 3000 yards of 2-inch braces are woven upon a 
 similar loom in the same time. But one of Mr. Sievier's most curious patent inven- 
 tions, is that of producing, by the shrinking of the caoutchouc threads in the founda- 
 tion or warp of the stuff, the appearance of raised figures, closely resembling coach 
 lace, in the weft. Thus, by a simple physical operation, there is produced, at an ex- 
 pense of one penny, an effect which could not be effected by mechanical means for less 
 than one shilling. 
 
 III. OF THE WATER-PROOF DOUBLE FABRICS. 
 
 The parings, the waste of the kneading operations above described, and the coarsest 
 qualities of imported caoutchouc, such as the inelastic lumps from Para, are worked up 
 into varnish, wherewith two surfaces of cloth are cemented, so as to form a compound 
 fabric, impervious to air and water. The caoutchouc is dissolved either in petroleum 
 (coal-tar) naphtha, or oil of turpentine, by being triturated with either of the solvents in 
 a close cast-iron vessel, with a stirring apparatus, moved by mechanical power. The heat 
 generated during the attrition of the caoutchouc, is sufficient to favour the solution, 
 without the application of fuel in any way. These triturating cylinders have been called 
 pug mills by the workmen, because they are furnished with obliquely pressing and re- 
 volving arms, but in other respects they differ in construction. They are 4 feet in 
 diameter and depth, receive 13 cwt. at a time, have a vertical revolving shaft of wrought 
 iron 4 inches in diameter, and make one turn in a second. Three days are required to 
 complete the solution of one charge of the varnish materials. The proportion of the 
 solvent oils varies with the object in view, being always much less in weight than the 
 caoutchouc. 
 
 When the varnish is to be applied to very nice purposes, as bookbinding, &c, it 
 must be rubbed into a homogeneous smooth paste, by putting it in a hopper, and letting 
 it fall between a couple of parallel iron rolls, set almost in contact. 
 
 The wooden framework of the gallery in which the waterproof cloth is manufactured, 
 should be at least 50 yards long, to give ample room for extending, airing, and drying 
 the pieces; it should be 2 yards wide, and not less than 5 high. It is formed of up- 
 right standards of wood, bound with three or four horizontal rails at the sides and the 
 ends. At the end of the gallery, where the varnish is applied, the web which is to be 
 smeared must be wound upon a beam, resembling in size and situation the cloth beam 
 of the weaver's loom. The piece is thence drawn up and stretched in a horizontal 
 direction over a bar, like the breast beam of a loom, whence it is extended in a some- 
 what slanting direction downwards, and passed over the edge of a horizontal bar. 
 Above this bar, and parallel to it, a steel-armed edge of wood is adjusted, so closely as 
 to leave but a narrow slit for the passage of the varnish and the cloth. This horizontal 
 slit may be widened or narrowed at pleasure by thumb screws, which lower or raise the 
 movable upper board. The caoutchouc paste being plastered thickly with a long 
 spatula of wood upon the down- sloped part of the web, which lies between the breast- 
 beam and the above-described slit, the cloth is then drawn through the slit by means of 
 
,56 
 
 CHALYBEATE. 
 
 cords in a horizontal direction along the lowest rails of the gallery, whereby it gets 
 uniformly besmeared. As soon as the whole web, consisting of about 40 yards, is thus 
 coated with the viscid varnish, it is extended horizontally upon rollers, in the upper 
 part of the gallery, and left for a day or two to dry. A second and third coat are then 
 applied in succession. Two such webs, or pieces, are next cemented face to face, by 
 passing them, at the instant of their being brought into contact, through between a 
 pair of wooden rollers, care being taken by the operator to prevent the formation of any 
 creases, or twisting of the twofold web. The under one of the two pieces being intended 
 for the lining, should be a couple of inches broader than the upper one, to insure the 
 uniform covering of the latter, which is destined to form the outside of the garment. 
 The double cloth is finally suspended in a well-ventilated stove room, till it becomes 
 day, and nearly free from smell. The parings cut from the broader edges of the under 
 piece, are reserved for cementing the seams of cloaks and other articles of dress. The 
 tape-like shreds of the double cloth are in great request among gardeners, for nailing 
 up the twigs of wall shrubs. 
 
 Mr. Walton, of Sowerby-bridge, has recently substituted sheet India rubber for 
 leather, in the construction of fillet cards for the cotton and tow manufactures. The 
 superior elasticity of this article is said to prove advantageous in several respects. 
 
 Mr. Charles Keene, proprietor of the extensive and well-organized India-rubber 
 factory in Lambeth, obtained a patent in March 1840, for applying a coat of 
 caoutchouc to the outer surface of flexible leather. The varnish of caoutchouc, 
 made with oil of turpentine, has so much lampblack incorporated with it, as to bring 
 it to the consistence of dough. The edge of the doe-skin, buck-skin, or wash- 
 leather, being introduced between a pair of wetted iron rollers, as much of the India- 
 rubber compound, softened by a gentle heat, and rolled into a proper length as will 
 cover the leather, is laid in the hollow between the leather and the moist cylinders. 
 By their rotation, the coating is evenly effected. When the surface has become dry, it 
 may be embossed or gilt, and varnished over with a solution of shellac, with a little 
 Venice turpentine, in alcohol. After two or three applications of this kind, the leather 
 is passed through a pair of rollers, either smoooth or embossed. When made up 
 articles, such as shoes or portmanteaus, &c, are to be covered, the India-rubber varnish 
 is used in a thinner state. — Newton's Journal, xxiii. 357. 
 
 CARMINE. This valuable pigment is often adulterated with starch. Water of 
 ammonia enables us to detect this fraud by dissolving the pure carmine, and leaving 
 the starchy matter, as well as most other sophisticating substances. Such debased 
 carmine is apt to spoil with damp. 
 
 CASSAVA, or Tapioca, is obtained principally from the Jatropha Manioc. Its 
 extraction is remarkable for the large quantity of hydrocyanic acid which the juice of 
 that plant contains. When distilled it affords, as a first product, a liquor which, in 
 the dose of 30 drops, will cause the death of a man in the course of six minutes ; and 
 it is well known that this acid does not pre-exist in the plant, but that it is generated 
 in it, after it is grated down into a pulp. It would be interesting to discover in what 
 state the substance exists, from which it proceeds. After the grating of the root, and 
 washing of the pulp, this is dried upon hot plates, to agglutinate it into the form of 
 concretions, constituting the tapioca of commerce. But the starch of the washed root 
 floated in water, is spontaneously deposited, and, when dried in the sun, forms Cassava 
 flour, called moussache by the French. 
 
 CASTOR OIL. Imported for consumption in 1839, 710,344 lbs. ; in 1840, 
 807,175 lbs. : duty, Is. 3d. per cwt. 
 
 CEMENTS. See Mortar, Hydraulic. 
 
 An excellent cement for resisting moisture is made by incorporating thoroughly 
 eight parts of melted glue, of the consistence used by carpenters, with four parts of 
 linseed oil, boiled into varnish with litharge. This cement hardens in about forty-eight 
 hours, and renders the joints of wooden cisterns and casks air and water tight. A 
 compound of glue with one fourth its weight of Venice turpentine, made as above, 
 serves to cement glass, metal, and wood, to one another. Fresh-made cheese curd, and 
 old skim-milk cheese, boiled in water to a slimy consistence, dissolved in a solution of 
 bicarbonate of pofash, are said to form a good cement for glass and porcelain. The 
 gluten of wheat, well prepared, is also a good cement. White of eggs, with flour and 
 water well mixed, and smeared over linen cloth, forms a ready lute for steam joints in 
 small apparatus. 
 
 Whitelead ground upon a slab with linseed oil varnish, and kept out of contact of 
 air, affords a cement capable of repairing fractured bodies of all kinds. It requires a 
 few weeks to harden. When stone and iron are to be cemented together, a compound 
 of equal parts of sulphur with pitch answers very well. 
 
 CHALYBEATE. Is the name given in medicine to preparations of iron. The 
 most agreeable, and one of the most powerful, forms of such medicines, is the im- 
 
CHAMELEON MINERAL. 
 
 57 
 
 proved chalybeate water, for which Mr. Henry Bewley, apothecary in Dublin, ob- 
 tained a patent in June, 1842. The following is his valuable recipe: — Eight ounces 
 of crystallised citric acid being dissolved in about four times their weight of water 
 heated to 170° F., are saturated with pure peroxide of iron, in the washed state, after 
 being precipitated by ammonia from the ferric sulphate. The solution is sweetened, 
 flavoured, and charged highly with carbonic acid gas, so as to make a very palatable 
 potion, agreeable also to the stomach. 
 
 I find by analysis that 100 parts of Mr. Bewley's brilliant citrate of iron contain 
 28*5 of peroxide, 48'5 of citric acid, and 23 of water ; and that a six-ounce phial of his 
 chalybeate water contains of that citrate a quantity equivalent to nearly 8 grains of 
 peroxide of iron. 
 
 Similar compounds are also specified to be made with other organic salts, as the 
 tartrate or lactate of iron. — Newton's Journal, xxii. 470. 
 
 CHAMELEON MINERAL. As this compound — so long known in chemistry 
 as a mere curiosity, on account of the surprising changes of colour which it spon- 
 taneously assumes — has of late been largely employed for whitening tallow, palm oil, 
 and decolouring other organic matters, it merits description in this dictionary. It 
 exists in two states ; one of which is called by chemists the manganate of potash, and 
 the other the oxymanganate ; denoting that the first is a compound of manganic acid 
 with potash, and that the second is a compound of oxymanganic acid with the same 
 base. They are both prepared in nearly the same way ; the former by calcining 
 together, at a red heat in a covered crucible, a mixture of one part of the black per- 
 oxide of manganese with three parts of the hydrate of potash (the fused potash of the 
 apothecary). The mass is of a green colour when cold. It is to be dissolved in cold 
 water, and the solution allowed to settle, and become clear, but by no means filtered 
 for fear of the decomposition to which it is very prone. When the decanted liquid is 
 evaporated under the exhausted receiver of an air-pump, over a surface of sulphuric 
 acid, it affords crystals of a beautiful green colour, which should be laid on a clean 
 porous brick to drain and dry. They may be preserved in dry air, but should be kept 
 in a well-corked bottle. They are decomposed by water, but dissolve in weak water 
 of potash. On diluting this much, decomposition of the salt ensues, with all the 
 chameleon changes of tint ; red, blue, and violet. Sometimes a green solution of this 
 salt becomes red on being heated, and preserves this colour even when cold, but 
 resumes its green hue the moment it is shaken : it might, therefore, furnish the crafty 
 votaries of St. Januarius with an admirable means of mystifying the worshippers at his 
 shrine. The original calcined mass, in being dissolved, always deposits a considerable 
 quantity of a brown powder, which is a compound of the acid and peroxide of man- 
 ganese combined with water. Much of the potash remains unchanged, which may be 
 recovered. 
 
 The oxymanganate of potash is made by fusing, with a strong heat, a mixture of 
 equal parts of peroxide of manganese and hydrate of potash, or one part of peroxide 
 and two parts of nitre. The mass is to be dissolved in water, and, if the solution be 
 green, it should be reddened by the cautious addition of a few drops of nitric acid. 
 The clarified liquor is to be evaporated to the point of crystallisation. Even the 
 smallest crystals of this salt have such an intense red colour, that they appear black 
 with a green metallic reflection. In the air they gradually assume a steel grey hue, 
 without undergoing any essential change of nature. A very little of the salt reddens 
 a large body of water. The least portion of any organic matter added to the solution 
 of this salt reduces the oxymanganic acid to the state of peroxide, which precipitates 
 combined with water ; and the liquor becomes green or colourless, according to circum- 
 stances. 
 
 A more permanent oxymanganic salt may be made as follows : — Melt chlorate of 
 potash over a spirit lamp, and throw into it a few pieces of hydrate of potash, which 
 immediately dissolve, and form a limpid liquid. When peroxide of manganese in fine 
 powder is gradually introduced into that melted mixture, it immediately dissolves, 
 with the production of a rich green colour. After adding the manganese in excess, 
 the whole is to be exposed to a gentle red heat, in order to decompose the residuary 
 chlorate of potash. It is now a mixture of manganate of potash, chloride of potassium 
 and peroxide of manganese. It forms with water a deep green-coloured solution ; which 
 when boiled assumes, a fine red colour, in consequence of its becoming an oxyman- 
 ganate, and it ought to be decanted off the sediment while hot. By cooling, and still 
 more after further evaporation, the oxymanganate of potash separates in crystals pos- 
 sessed of great lustre ; but towards the end colourless crystals of chloride of potassium. 
 
 Both the above salts are readily decomposed by organic bodies and other com- 
 bustibles, whereby they have their acid converted into an oxide, with the disengage- 
 ment of oxygen, and the destruction of many vegetable and animal colours. In this 
 respect they resemble the nitrates and chlorates. 
 
 I 
 
58 
 
 CHOCOLATE. 
 
 CHINA INK. (Encre de Chine, Fr. ; Chinesischcr Tusch, Germ.) The finest 
 kind of this useful pigment is seldom met with in our markets. According* to a de- 
 scription in a Japanese book, it is made from the condensed smoke or soot of burned 
 camphor ; and hence, when of the best quality, it has this odour. Most of the China 
 ink is made from oil-lampblack occasionally disguised, as to smell, with musk, or 
 with a little camphor black. The binding substance is gelatine, commonly made from 
 parchment or ass's skin ; but isinglass answers equally well. A good imitation ma)' 
 be made by dissolving isinglass in warm water, with the addition of a very little alkali 
 (soda), to destroy its gelatinizing power ; and incorporating with that solution, by levi- 
 gation on a porphyry slab, as much of the finest lampblack as to produce a mass of 
 the proper consistence. The minute quantity of alkali serves also to saponify the oil 
 which usually adheres to lampblack ; and thereby to make a pigment readily miscible 
 with water. 
 
 CHLORATE OF POTASH. The following ingenious and easy way of making 
 this valuable compound has been lately suggested by Professor Graham : — Mix equal 
 atomic weights of carbonate of potash and hydrate of lime (70 of the former, if pure, 
 and 37 of slaked lime in powder), diffuse them through cold water, and transmit 
 chloride gas through the mixture. The gas is absorbed with great avidity, and the 
 production of a boiling heat. When the saturation is complete, carbonate of lime re- 
 mains, and a mixture of muriate and chlorate of potash, which latter salts are to be 
 separated, as usual, by the difference of their solubility in water. 
 
 It has been remarked on the above process, that it effects no saving of potassa, and 
 therefore is far inferior to the one long practised in several parts of Germany, especially 
 at Giessen, and introduced into this country a good many years ago by Dr. Wagen- 
 mann, from Berlin. The chlorine is passed into a mixture of one equivalent of chlo- 
 ride of potassium (76), and 6 equivalents of hydrate of lime (222), previously stirred with 
 water, to the consistence of a thin paste. Thus the calcium of the lime unites with the 
 chlorine to form chloride of calcium, while the chloride of potassium is converted into 
 chlorate of potassa, which salt is easily separated in crystals by its sparing solubility. 
 
 Chlorate of potash may also be made by saturating with chlorine a mixture of 74 
 parts of chloride of potassium (muriate of potash) and 168 parts of quicklime, brought 
 to the consistence of a thin pap by the cautious addition of water. The mass being 
 dissolved in warm water, and evaporated and cooled, yields crystals of chlorate of 
 potash, while a mother water of chloride of calcium (muriate of lime), remains. The 
 following process has likewise been prescribed: — Mix 10 parts of good chloride of 
 lime with water into a pap, and evaporate to dryness, whereby it is converted into 
 a mixture of chloride of calcium and chlorate of lime, devoid of bleaching power : 
 dissolve it in water, filter, concentrate the solution by evaporation, then add to it 1 
 part of chloride of potassium, and cool for crystallisation. The salt which may thereby 
 be separated from the chloride of calcium will afford 0*83 of pure chlorate of potash. By 
 this process of Professor Liebig five sixths of the potash are saved, but much oxygen is 
 wasted in the evaporation to dryness of the chloride of lime, and, consequently, much 
 chloric acid is lost towards the production of the salt. Vee mixes the chloride of lime 
 pap, before heating it, with the chloride of potassium, boils the mixture smartly, whereby 
 much oxygen is undoubtedly thrown off, and then sets the liquor aside to crystallise. 
 L. Gmelin suggests that saturation of the liquor with chlorine before boiling might 
 be advantageous. Gay Lussac has suggested to make this valuable salt by pre- 
 cipitating a solution of chloride of lime with carbonate (or sulphate) of potash, 
 saturating the liquor after filtration with chlorine gas, evaporating, and crystallising. 
 
 Professor Juch's process is to pass chlorine gas into a mixture of 1 pound caustic 
 lime and 1 pound carbonate of potash, with 8 pounds of water. The resulting chloride 
 of potash readily separates in the filtered liquid by crystallization, from the very 
 soluble chloride of calcium. By this method, potash is not wasted in the useless 
 production of chloride of potassium. 
 
 CHOCOLATE. About eighteen months ago, samples of chocolate were sent to me 
 for analysis, by order of the Lords of the Admiralty. It was made at the victualling- 
 yard, Deptford, for the use of the Royal Navy, by the government chocolate-mills, 
 where about 400 tons are annually prepared, to be distributed to the sailors and con- 
 victs at the rate of an ounce daily, and to be used at their breakfast. After taking the 
 said chocolate for some time, men in several ships complained of its occasioning sick- 
 ness, vomiting, purging, and more serious maladies, terminating in a few cases fatally. 
 I examined it with great care, but could find no injurious ingredient in it, and no 
 chemical alteration from the beans of the Guyaquil coco from which it was manu- 
 factured. But I observed that it consisted of gritty grains, from very imperfect tri- 
 turation or milling ; that these grains were quite immiscible with water, like so much 
 tine gravel ; that they contained many sharp spicula? of the coco-bean husks, and that 
 hence, when swallowed, they were calculated to form mechanically irritating lodge- 
 
CHOCOLATE. 
 
 59 
 
 ments in the villous coats of the stomach and bowels, whereby they could produce the 
 morbid effects certified by several naval surgeons. It was, moreover, obvious that, 
 from the insoluble condition of the chocolate, it could be of little use as an article of 
 food, or as a demulcent substitute for milk, and that, in fact, three -fourths of it were, 
 on this account, an ineffective article of diet ; or were wasted. 
 
 Having reported these results and opinions to the Lords of the Admiralty, they 
 were pleased, after a few weeks' consideration, to request me to go down to the vic- 
 tualling-yard at Deptford, and superintend the preparation of a quantity of chocolate 
 in the best manner I could with the means there provided. I accordingly repaired, 
 thither on the 13th September, 1 842, and experienced the utmost courtesy and co- 
 operation from Sir John Hill, the Captain Superintendent, and his subordinate officers. 
 The coco-beans had been heretofore milled, after a slight roasting upon the sole of an 
 oat- kiln, along with their husks. As I was satisfied, from analysis, that the husks 
 were no better food than sawdust, and that they might cause irritation by their minute 
 spicuke left after grinding between rotating millstones, I set about a plan for shelling 
 them, but could find no piece of apparatus destined for the purpose. There was, how- 
 ever, a pea-shelling mill, which had been used only for one day some years before, and 
 had stood ever since idle*, which, on being cleaned and having its millstones placed at 
 a proper distance, was found to answer pretty well. The beans for experiment, to the 
 amount of 6 cvvt., had been previously roasted, under my care, at a well-regulated 
 heat, with much stirring, in the oat-kiln ; and, on being cold, were run through the 
 shelling mill, which was put in communication with the fanners of the flour mill. 
 By this arrangement, the coco-beans were tolerably shelled, and the kernels separated 
 from their scaly husks. The weighings were accurately made. 
 
 6 cwt. of the Guyaquil coco - - -672 lbs. 
 
 Lost in roasting - - 43 ~] 
 
 shells - - 54 l 117 
 
 waste - - 20 J 
 
 Remained for milling - - 555 
 
 On the 14th September I made a report to the Lords of the Admiralty upon the 
 experiments of the 13th, of which the following is an outline. After describing the 
 pains taken to regulate the roasting temperature, and to equalize the effect upon 
 the beans by moving them occasionally by a rake, I stated that the oat-kiln was not well 
 adapted to the purpose of roasting the coco, because it was impossible to turn the beans 
 regularly and continuously during the process, so that they could not be equally roasted, 
 and because it was an unwholesome operation for the workmen, who must go into a 
 chamber filled with noxious gases and fumes, to use the rakes. When the door of the 
 kiln was shut, to allow the burned air from the fire below to draw up through it, mischief 
 might be done to the stratum of coco on the sole, and when the door was again opened, 
 to permit a person to go in and stir, time and heat were wasted in replenishing the 
 chamber with fresh air. I understand that a revolving-cylinder-roasting machine had 
 been made by Messrs. Rennie for the chocolate process at Deptford ; but, for reasons 
 unknown to me, it had never been employed. 
 
 The diminution of weight by roasting and shelling may be estimated at about 1 7 
 per cent. A part of this loss is moisture, which should be completely expelled, to 
 prevent its causing the chocolate to become mouldy at sea. But a part of the defal- 
 cation was also due to some of the coco remaining in the crevices of the pea-splitting 
 mill and the fanners, which would not be observable if these were in constant employ- 
 ment. I think, therefore, that the roasted kernels may be estimated in general at 85 
 per cent, of the raw beans. 
 
 Fig. 20. represents the chocolate mills at the victualling-yard, Deptford, as 
 mounted by the celebrated engineers, Messrs. Rennie. There are four double mill- 
 stones, a, b, c, n, each three feet in diameter, of which the nether rests upon a bed of 
 cast iron, like a drum-head, kept at the temperature of about 220° by the admission of 
 steam to the case below. Over each mill there is a feeding-hopper 1, 2, 3, 4, in com- 
 munication by the pipes 5, 6, 7, 8, with the general reservoir e, charged upon the floor 
 above with coco through the funnel placed over it. The vertical shafts which turn 
 these mills are marked f, g, h, l ; they are moved by the train of bevil wheels above, 
 which are driven by an arm from the main shaft of the steam engine. Each mill can, 
 of course, be thrown in and out of geer at pleasure. At I, i, i, i, the discharge-spout 
 is shown, which pours out the semi-fluid hot chocolate into shallow cylindrical tin pans, 
 
 * It was found that peas in their skin kept better at sea than the split peas, and they were also pre- 
 ferred by the sailors in their natural state. 
 
 I 2 
 
60 
 
 CHOCOLATE. 
 
 capable of containing about nine pounds of cbocolate eacb. These four mills are capable 
 of converting upwards of a ton of coco into good cbocolate in a day, on tbe system of 
 double trituration which I adopted, and two tons on the former rough plan. I found 
 that the two stones of each mill had been placed so far asunder as would allow entire 
 
 beans to pass through, as spurious chocolate, at one operation ; but the chocolate thus 
 discharged was in a very gritty state, whereas good chocolate in the liquefied state should 
 be smooth and plastic between the fingers, and spread upon the tongue without leaving 
 any granular particles in the mouth. To obtain such a result, I divided the milling 
 into two steps ; for the first, two pairs of the stones, a and c, were set as close together 
 as for a paint mill (which they closely resemble), and the other two pairs, b and r>, 
 were left at their ordinary distance. The paste obtained from the first set was trans- 
 ferred, while nearly liquid, into the hoppers of the second pairs, from which it issued at 
 the spouts as thin and smooth as honey from the comb. In subserviency to these ex- 
 periments, I made an analysis of the Guyaquil coco, which I found to be composed as 
 follows : — 
 
CHOCOLATE. 
 
 61 
 
 Concrete fat or butter of coco, dissolved out by ether - -37 
 
 Brown extractive, extractible by hot water, after the operation of ether 10 
 Ligneous matter, with some albumine - - - - 30 
 
 Shells - - - - - - - -14 
 
 Water 6 
 Loss ---------3 
 
 100 
 
 The solid fat of the coco should be most intimately combined by milling with the 
 extractive, albumine, and ligneous matter, in order to render it capable of forming an 
 emulsion with water ; and, indeed, on account of the large proportion of concrete fat in 
 the beans, some additional substance should be introduced to facilitate this emulsive 
 union of the fat and water. Sugar, gum, and starch or flour are well adapted for this 
 purpose. 
 
 Under this conviction, I employed in the first of these trials at Deptford, made 
 with one half of the above roasted kernels = 277^ lbs., 5 per cent, of sugar, which was 
 first mixed upon a board with shovels, and the mixture was then put progressively into 
 the hoppers of the two mills b and d. The paste which ran out of their spouts, was 
 immediately poured into the hoppers of a and c, from which it flowed smooth and very 
 thin into the concreting pans. The sugar supplied to me was exceedingly moist, 
 whereas it ought to be dry, like the bag sugar of the Mauritius. The other half 
 of the coco kernels was milled alone once by the ordinary mills B and d. I sub- 
 jected next day samples of these two varieties of chocolate to the following examin- 
 ation, and compared them with the sample of chocolate as usually made at Deptford, 
 as also with a sample of chocolate sold by a respectable grocer in London. A like 
 quantity of these four samples was treated with eight times its weight of boiling water, 
 the diffusion well stirred, and then left to settle in a conical wineglass. Of the ordinary 
 Deptford coco, four-fifths rapidly subsided in coarse grains, incapable of forming any 
 thing like an emulsion with water, and therefore of little or no avail in making a break- 
 fast beverage. 
 
 1. The single-milled chocolate made under my direction formed a smoother emul- 
 sion than the last, on account of the absence of the coco husks ; but its particles were 
 gritty, and subsided very soon. 
 
 2. The sugared double-milled chocolate, on the contrary, formed a milky-looking 
 emulsion, which remained nearly uniform for some time, and then let fall a soft 
 mucilaginous deposit, free from grittiness. 
 
 3. The shop chocolate formed a very indifferent emulsion, though it was well 
 milled, because it contained evidently a large admixture of a coarse branny flour, as is 
 too generally the case. 
 
 1 have given small samples of the above No. 2. chocolate to various persons, and 
 they have considered it superior to what is usually sold by our grocers. The presence 
 of dry sugar in chocolate would also give it a conservative quality at sea, and prevent it 
 from getting musty. 
 
 The Lords of the Admiralty, after seeing the above two samples of chocolate, and 
 my report thereupon, were, about six weeks afterwards, pleased to request me to make 
 at their victualling-yard further experiments in the preparation of chocolate ; and they 
 indicated two modes, one of milling twice with the husks, and another of milling twice 
 without the husks ; permitting me, at the same time, to mill a portion of the kernels 
 with lOper cent, of sugar, and a second portion of the kernels with 5 per cent, of sugar 
 and 5 per cent, of the excellent flour used in making the biscuits for the royal navy. On 
 the 24th October, 1842, I accordingly performed these experiments upon 12 cwt. of 
 Guyaquil coco as carefully roasted as possible on the kiln. 
 
 The loss in drying and slightly roasting the 1344 lbs. of beans was 5 per cent. 
 
 1st experiment, 212 lbs. of roasted coco, milled twice with the husks, 
 
 produced, of chocolate 209 lbs. 
 
 2d experiment, 191 lbs. ditto, milled twice without husks - - 189 
 
 3d experiment, 191 lbs. kernels, milled once along with 19 lbs. of sugar 
 
 = 210 lbs. - 212* 
 
 4th experiment, 573 lbs. of kernels, milled twice along with 68 lbs. of 
 flour and 34 of sugar = 675 - ggg 
 
 Sample cakes of these four varieties of chocolate were subsequently sent to me for 
 examination and report. I found that the chocolate milled twice with the flour and 
 
 * This small excess proceeded from a residue of the last experiment. 
 
62 
 
 COFFEE. 
 
 sugar formed a complete emulsion with hot water, hland and rich, like the best milk, 
 but the other three were much inferior in this respect. Sugar alone, with proper 
 milling, would serve to give the kernels of well roasted coco a perfect emulsive pro- 
 perty. Instead of merely milling with rotatory stones, I would prefer, for the second 
 or finishing operation, a levigating mill, in which rollers would be rolled either back- 
 wards and forwards, or, when slightly conical, in a circular direction, over a plane 
 metallic, marble, or porphyry, slab, as is now, indeed, very generally practised by the 
 trade. The coco-beans should be well selected, without musty taint, and possessed 
 of a fine aroma, like the best of that imported from Trinidad. There is a great 
 deal of very coarse coco and chocolate on sale in London and in the provincial towns 
 of the United Kingdom. 
 
 Fig. 21. is an end view of one of the chocolate mills with 
 its mitre-gearing. I consider the gritty chocolate hitherto 
 made at Deptford as a very bad substitute for the chocolate 
 which was made from coco by the sailors themselves with a 
 pestle and mortar. 
 
 In 1840 the coco cleared for consumption in the United 
 Kingdom was : — 
 
 British plantation 
 Foreign 
 
 Coco-nut husks and shells 
 Chocolate and coco paste 
 
 - 2,041,492 lbs. 
 186 
 
 753,580 
 2,067 
 
 Rate of Duty. 
 2d. per lb. 
 6d. 
 Id. 
 4d. 
 
 Of the coco-nut shells, 612,122 lbs. were consumed in 
 Ireland ! and less than 4000 lbs. of coco. 
 
 Of coco, 726,116 lbs. were consumed in Her Majesty's navy. 
 How scurvily are the people of Ireland treated by their own 
 grocers ! Upwards of 600,000 lbs. of worthless coco husks 
 served out to them along with only 4000 lbs. of coco-beans ! 
 CHROMIUM, OXIDE OF. Mix intimately 45 parts of gunpowder with 240 
 parts of perfectly dry chromate of potash, and 35 parts of hydrochlorate of ammonia (sal 
 ammoniac), reduce to powder, and pass through a fine sieve ; fill a conical glass or other 
 mould with this powder, gently pressed, and invert so as to leave the powder on a 
 porcelain slab of any kind. When set on fire at its apex with a lighted match, it will 
 burn down to the bottom with brilliant corruscations. The black residuum, being 
 elutriated with warm water, affords a fine bright green oxide of chromium. 
 CLOVES. Imported for home consumption in 1840, 85,769 cwts. 
 COAL. Under Pitcoal, the composition of several excellent coals, is stated, with 
 their peculiar qualities, as analysed by me ; such as the Llangennoek, Powell's Duffryn 
 steam coal, the Blackley Hurst coal Lancashire, the Varley Rock vein coal, near 
 Pontypool, &c. 
 
 COCHINEAL. Imported for consumption in 1839, 396,902 lbs. ; in 1840, 
 325,744 : duty, Is. per cwt. 
 
 COFFEE. If tannin exist in roasted coffee, as maintained long ago by Chenevix, 
 and generally admitted since, it must be very different from the tannin present in tea, 
 catechu, kino, oak-bark, willow-bark, and other astringent vegetables ; for I find that 
 it is not, like them, precipitated by either gelatine, albumen, or sulphate of quinine. With 
 regard to the action, upon the animal economy, of coffee, tea, and cocoa, which contain 
 one common chemical principle called caffeine or theine, Liebig has lately advanced some 
 ingenious views, and has, in particular, endeavoured to show that, to persons of sedentary 
 habits in the present refined state of society, they afford eminently useful beverages, 
 which contribute to the formation of the characteristic principle of bile. This important 
 secreted fluid, deemed by Liebig to be subservient to the function of respiration, 
 requires for its formation much azotised matter, and that in a state of combination 
 analogous to what exists in caffeine. The quantity of this principle in tea and coffee 
 being only from 2 to 5 per cent., might lead one to suppose that it could have little effect 
 upon the system even of regular drinkers of their infusions ; but if the bile contains only 
 one tenth of solid matter, called choleic acid, which contains less than 4 per cent, of 
 azote, then it may be shown that 3 grains of caffeine would impart to 500 grains of 
 bile the azote which occurs in that crystalline precipitate of bile called taurine, which 
 is thrown down from it by mineral acids. 
 
 One atom of caffeine', 9 atoms of oxygen, and 9 of water, being added together, " 
 produce the composition of 2 atoms of taurine. Now this is a very simple combin- 
 ation for the living organism to effect ; one already paralleled in the generation of 
 hippuric acid in urine, by the introduction of benzoic acid into the stomach ; a physio- 
 
CREOSOTE. 
 
 63 
 
 logical discovery made by my son, which is likely to lead to a more successful treat- 
 ment of some of the most formidable diseases of man, particularly gout and gravel. 
 
 If the preceding views be established, they will justify the instinctive love of man- 
 kind for tea, coffee, and cocoa, in spite of the denunciations and vetos of neuropathic, 
 homcEopathic, and hydropathic doctors; sorry pathologists — hoc genus omne. See Tea. 
 
 Coffee imported for consumption in 1839, 26,789,945 lbs. : in 1840, 28,664,341. 
 Net revenue in 1839, 779,115/. ; in 1840, 921,551/. 
 
 COPAL and ANIME. Imported for consumption in 1839, 193,066 lbs. ; in 1840, 
 181,388 lbs. : duty, 6s. per cwt., as upon gum arabic and tragacanth. 
 
 COPPER. Quantity of copper ore raised in Cornwall in the year 1838-1839, 
 1 59,21 4 tons ; value of, 932,090/. 1 5s. 6d. 
 
 Quantity raised in the year 1839-1840, 147,049 tons; value of, 792,750/. 14.s. 
 
 Quantity of metallic copper produced in the former year, 12,469 tons; standard 
 111/. : in the latter, 11,056; standard, 108/. 5s. 
 
 Produce per cent. 7| and 7 A respectively. Average price per ton, 51. 17s. in the 
 first ; and 51. 7s. 9d. in the second year. 
 
 Quantity of unwrought copper imported for home consumption in 1840, only 
 2\ cwts. See Metallic Statistics. 
 
 "COPPER MEDALS AND MEDALLIONS may be readily made in the fol- 
 lowing way : — Let black oxide of copper, in a fine powder, be reduced to the metallic 
 state, by exposing it to a stream of hydrogen, in a gun-barrel, heated barely to redness. 
 The metallic powder thus obtained is to be sifted through crape, upon the surface of 
 the mould, to the thickness of \ or i of an inch, and is then to be strongly pressed upon 
 it, first by the hand, and lastly by percussion with a hammer. The impression thus 
 formed is beautiful ; but it acquires much more solidity by exposure to a red heat, out 
 of contact with air. Such medals are said to have more tenacity than melted copper, 
 and to be sharply defined. 
 
 M. Boettger proposes the following improvement upon the above plan of Mr. Osann, 
 He prepares the powder of copper easier and of better quality, by precipitating a 
 boiling hot solution of sulphate of copper, Avith pieces of zinc, boiling the metallic 
 powder thus obtained with dilute sulphuric acid for a little, to remove all traces of the 
 zinc or oxide, washing it next with water, and drying it in a tubulated retort by the 
 heat of a water bath, while a stream of hydrogen is passed over it. This cupreous 
 precipitate possesses so energetic an affinity for oxygen, that it is difficult to prevent its 
 passing into the state of orange oxide. If it be mixed with one half its atomic weight 
 of precipitated sulphur, and the two be ground together, they combine very soon into 
 sulphuret of copper with the evolution of light. 
 
 COPPER, Purifying. — Copper may be purified by melting 100 parts of it with 10 
 parts of copper scales (black oxide), along with 10 parts of ground bottle-glass or other 
 flux. Mr. Lewis Thompson, who received a gold medal from the Society of Arts for 
 this invention, says that after the copper has been kept in fusion for half an hour, it will 
 be found at the bottom of the crucible perfectly pure ; while the iron, lead, arsenic, &c, 
 with which this metal is usually contaminated, will be oxidised by the scales, and will 
 dissolve in the flux, or be volatilised. Thus he has obtained perfectly pure copper 
 from brass, bell-metal, gun-metal, and several other alloys, containing from 4 up to 50 
 per cent, of iron, lead, antimony, bismuth, arsenic, &c. The scales of copper are cheap, 
 being the product of every large manufactory where that metal is worked. 
 
 CORK. Unmanufactured, imported in 1840 for home consumption, 59,793 cwts. 
 
 CORTEX PERUVIANUS, or CINCHONA. Imported for home consump- 
 tion in 1840, 43,705 lbs. 
 
 COTTON may be distinguished from linen in a cloth fabric by means of a good 
 microscope ; the former fibres being flat, riband-like, and more or less contorted or 
 shrivelled, and the latter straight, round, and with cross knots at certain distances. 
 These two fibrous matters may be also distinguished by the action at a boiling heat of 
 a strong caustic lye, made by dissolving fused potash in its own weight of water. By 
 digestion in this liquor, linen yarn becomes immediately yellow, while the cotton yarn 
 remains white. The best way of operating is to immerse a square inch of the cloth to 
 be tested for two minutes in the above boiling hot caustic lye, to lift it out on a glass 
 rod, press it dry between folds of blotting-paper, and then to pull out a few of the 
 warp and weft threads — when the linen ones will be found of a deep yellow tint, but 
 the cotton, white or very pale yellow. 
 
 COTTON WOOL. Imported for home consumption in 1839, 352,000,277 lbs.; 
 ' in 1840, 528,142,743 lbs. 
 
 CREOSOTE. Having been employed by a chemical manufacturer to examine his 
 creosote, and compare" it with others with a view to the improvement of his process, I 
 found that the article, as made by eminent houses, differed considerably in its pro- 
 perties. 
 
64 
 
 DAGUERftOTYPE. 
 
 The specific gravities varied in the several specimens as follows : — 1 . a spe- 
 cimen given me by Messrs. Zimmer and Sell, at their factory in Sachsenhausen, by 
 Frankfurt on the Maine, had a specific gravity of 1 *0524 ; 2. a sample made in the 
 north of England, sp. gr. 1 -057, and its boiling point varied from 370° to 380° F. 
 Mr. Morson's creosote, which is much esteemed, has a sp. gr. of 1 *070, and boils first 
 at 280°, but progressively rises in temperature up to 420°, when it remains stationary. 
 The German creosote was distilled from the tar of the pyrolignous acid manufacture. 
 Creosote, I believe, is often made from Stockholm tar. Berzelius gives the sp. gr. 
 of creosote &t 1 -037, and its boiling point at 203° C. = 397'4° F. I deemed it useless 
 to subject to ultimate analysis products differing so considerably in their physical pro- 
 perties. They were all very soluble in potash lye. 
 
 CROSS- FLUCKANS or FLOOKANS. The name given by the Cornish miners 
 to clay veins of more ancient formation. 
 
 CYANIDE OF POTASSIUM. This salt, so much used now in the electrotype 
 processes, is prepared, according to Liebig's formula, by mixing 8 parts of pounded 
 prussiate of potash, sharply dried, Avith 3 parts of pure carbonate of potash, fusing the 
 mixture in an iron crucible, by a moderate red heat, and keeping it so, till the glass 
 or iron rod with which the fluid mass should be occasionally stirred, comes out covered 
 with a white crust. The crucible is then to be removed from the fire ; and after the 
 disengaged iron has fallen to the bottom, the supernatant fluid, still obscurely red hot, 
 is to be poured off upon a clean surface of iron or platinum. After concretion and 
 cooling, the white saline mass is to be pounded while hot, and then kept in a well- 
 stopped bottle. It consists of about 5 parts of cyanide of potassium,"and 1 of cyanate 
 of potash. For most purposes, and the analysis of ores, the latter ingredient is no ways 
 detrimental. 
 
 CYDER. The value of apples to produce this beverage of good quality is propor- 
 tionate to the specific gravity of their juice. M. Couverchel has given the following 
 table, illustrative of that proposition : — 
 
 Juice of the green renette, queen apple (reinette verte) - - 1084 
 
 English renette ----- 1080 
 
 Red renette - - - - - 1072 
 
 Musk renette - 1069 
 
 Fouillet raye 1064 
 
 Orange apple ----- 1063 
 
 Renette of Caux 1060 
 
 Water - - - - - - 1000 
 
 Cyder apples may be distributed into three classes, the sweet, the bitter, and the 
 sour. The second are the best ; they afford a denser juice, richer in sugar, which 
 clarifies well, and when fermented keeps a long time ; the juice of sweet apples is diffi- 
 cult to clarify ; but that of the sour ones makes bad cyder. Late apples are in general 
 to be preferred. With regard to the proper soil for raising apple trees, the reader may 
 consult with advantage an able essay upon " The Cultivation of Orchards and the 
 making of Cyder and Perry," by Frederick Falkner, Esq., in the fourth volume of the 
 Royal Agricultural Journal. He adverts judiciously to the necessity of the presence 
 of alkaline and earthy bases, in the soils of all deciduous trees, and especially of such 
 as produce acid fruits* 
 
 In November, 2340 kilogrammes of apples (21 tons English, nearly) are supposed 
 to afford 1000 litres (220^ gallons) of pure cyder ; and 600 litres of a small cyder made 
 with the marc mixed with water and pressed. But many persons mix all together, and 
 thus manufacture 1 600 litres out of the above weight of fruit. In France, the fermented 
 liquor, as soon as it is clear, is often racked off into casks containing the fumes of 
 burning sulphur, whereby it ceases to ferment, and preserves much of its sugar unde- 
 composed. It is soon afterwards bottled. Average cyder should yield 6 per cent, of 
 alcohol on distillation. 
 
 D: 
 
 DAGUERROTYPE. This new and most ingenious invention, for producing 
 pictures by the action of light, is due to M. Daguerre and M. Niepce, two Frenchmen. 
 It was purchased from them by the French government for the benefit of the nation at 
 large ; but was made the subject of an exclusive patent in this country by M. Daguerre, 
 as our government never purchases any scientific invention. 
 
 The fixation of the images, formed in the focus of the camera obscura, is made on 
 very smooth surfaces of pure silver plated on copper. The process is divided into five 
 
DAGUERROTYPE. 
 
 (55 
 
 operations. 1. The first consists in polishing and cleaning the silver surface, by fric- 
 tion with cotton fleece imbued with olive oil, upon the plate, previously dusted over 
 with very finely-ground dry pumice-stone out of a muslin bag. The hand of the 
 operator should be moved round in circles, of various dimensions. The plates should 
 be laid upon a sheet of paper solidly supported. The pumice must be ground to 
 an impalpable powder upon a porphyry slab with water, and then dried. The sur- 
 face is next to be rubbed with a dossil of cotton, slightly moistened with nitric acid, 
 diluted with sixteen parts of water, by applying the tuft to the mouth of the phial of 
 acid, and inverting it for a moment. Two or three such dossils should be used in 
 succession. The plate is lastly to be sprinkled with pumice powder or Venetian 
 tripoli, and rubbed clean with cotton. 
 
 The next step is to heat the plate by placing it in a wire frame {Jig. 23.), with the 
 silver surface uppermost, over a spirit lamp, meanwhile moving it so as to act equally 
 on every part of the plate. In about five minutes a whitish coating will indicate that 
 this operation is completed. The plate must now be laid upon a flat metal or marble 
 slab to cool it quickly. The white surface is to be brightened by rubbing it with 
 cotton and pumice powder. It must be once more rubbed with the cotton imbued 
 with acid, and afterwards dried by friction with cotton and pumice ; avoiding to touch 
 the plate with the fingers, or with the part of the cotton held in them, or to breathe 
 upon the plate, since spots would thereby be produced. After cleaning with cotton 
 alone, the plate is ready for the next operation. 
 
 2. Here the following implements are required : 1 . the box represented in figs. 24. 
 and 25. ; 2. the thin board or frame, fig. 26. ; four small metallic bands of the same 
 
 
 
 
 b 
 
 b 
 
 \ i 
 
 li 
 
 
 b 
 
 
 E°-l ■ 
 
 d d a 
 
 D^l 
 
 d 
 
 ^ ec -n 
 
 
 
 metals as the plates, also shown in fig. 26., a small handle and a box of small nails or 
 tacks, and a phial of iodine. 
 
 After fixing, by the metallic bands and the small nails, the plate upon the thin 
 board, with the silver uppermost, several particles of iodine are then to be spread in 
 the dish d, at the bottom of the box, figs. 24. and 25. The thin board with the plate 
 is next placed, with the silver beneath, upon small supports at the four corners of the 
 box, and its cover is applied. • The plate must be left in this position till the surface of 
 the silver acquires a fine golden hue, caused by the vapours of the iodine rising through 
 the gauze cover of the dish, and condensing upon it ; but it should not be allowed to 
 assume a violet tint. The room should be darkened, and no heat should be employed. 
 When the box is in constant use it gets impregnated with iodine, and acts more uni- 
 formly and rapidly ; but in general states of the atmospheric temperature this operation 
 will be effected in about twenty minutes. If the purple colour be produced, the plate 
 must be repolished, and the whole process repeated. 
 
 The plate with its golden hue is to be introduced with its board into the frame, figs. 
 27, 28, 29., which is adapted to the camera obscura. During this transfer the light must 
 not be suffered to strike upon the surface of the plate ; on which account, the camera 
 obscura may be lighted briefly with a small wax taper. 
 
 K 
 
66 
 
 DAGUERROTYPE. 
 
 3. The plate is now submitted to the third operation, that of the camera obscura, 
 figs. 30. and 22. ; and with the least possible delay. The action of this machine is ob- 
 viously quicker the brighter the light which acts upon it ; and more correct, according 
 as the focus is previously accurately adjusted to the place of the plate, by moving 
 backwards and forwards a roughened pane of glass, till the focal point be found ; and 
 the plate is to be inserted precisely there, see figs. 27, 28, 29. This apparatus 
 exactly replaces the ground glass. While the prepared plate is being fastened, the 
 camera must be closed. The darkening shutters, b b, of the apparatus are opened by 
 means of the two semicircles a, a. The plate is now in a proper position to receive 
 and retain the impression of the image of the objects presented the moment that the 
 camera is opened. Experience alone can teach the proper length of time for sub- 
 mitting the plate to the concentrated rays of light ; because that time varies with the 
 climate, the seasons, and the time of day. More time should not be allowed to pass 
 than what is necessary for fixing a distinct impression, because the parts meant to be 
 clear would be apt to become clouded. 
 
 4. The fourth is the operation with quicksilver, which must follow as soon as pos- 
 sible the completion of the third. Here a phial of quicksilver, a spirit lamp (the 
 apparatus represented in figs. 31. and 32.), and a glass funnel with a long neck, are re- 
 quired. The funnel is used for pouring the mercury into the cup c, placed in the 
 bottom of the apparatus, so as to cover the bulb of the thermometer /. No day-light 
 must now be admitted, but that of a small taper only should be used by the operator 
 in conducting the process. The board with the plate is to be withdrawn from the 
 camera, and inserted into the grooves of the blackened board, b, fig. 31. This black 
 board is laid back into the box at an angle of 45 degrees with the horizon ; the pre- 
 pared metal surface A being placed undermost, so that it may be viewed through the 
 side glass, g ; and the cover, a, of the box must be put down gently to prevent any par- 
 
DAGUERROTYPE. 
 
 67 
 
 tides of mercury from being thrown about by the agitation of the air. The whole 
 being thus prepared, the spirit-lamp is lighted, and placed under the cup containing 
 the mercury, and left there until the thermometer indicates a temperature of 140° 
 Fahr., when the lamp is to be removed. The heat should in no case be permitted to 
 exceed 167° F. 
 
 The impression of the image of nature is now actually made upon the plate; but it 
 is as yet invisible ; and it is only after a lapse of several minutes that faint tracings of 
 the objects begin to be seen through the peep-glass by the momentary gleam of a 
 taper. The plate should be left in the box till the thermometer has cooled to 113° F., 
 when it is to be taken out. 
 
 After each operation, the interior of the apparatus, and the black board or frame, 
 should be carefully wiped, in order to remove every particle of mercury. 
 
 The picture may now be inspected in a feeble light, to see how far the process has 
 succeeded. The plate, freed from the metallic bands, is to be placed in a box, pro- 
 vided with a cover and grooves, to exclude the light, till it is made to undergo the fifth 
 and last operation, which may be done after any convenient interval of time without 
 detriment, provided the plate be kept in the dark. The following articles are now 
 required : — I, strong brine, or a weak solution of hyposulphite of soda; 2. the appa- 
 ratus represented in Jigs. 33. and 34.; 3. two troughs of tin-plate; 4. a jug of dis- 
 tilled water. The object of this process is to fix the photogenic picture. One of the 
 troughs is to be filled with brine to the depth of an inch, and the other with pure 
 water, both liquids being heated somewhat under the boiling pitch. The solution of 
 hyposulphite of soda is preferable, and does not need to be warm. The plate is to be 
 first immersed in the pure water for a moment, and transferred immediately to the 
 saline solution, and moved to and fro in it to equalise the action of the liquor. When- 
 ever the yellow tint of the iodine is removed, the plate is to be lifted out by the 
 edges, and dipped straightway in the water-trough. The apparatus of Jigs. 33. and 34. 
 is then brought into use, with a vessel filled with distilled water, hot, but not boiling. 
 The plate, when lifted out of the water-trough, is to be placed immediately on the 
 inclined plane e ; and without allowing it time to dry, is to be floated over with the 
 hot distilled water from the top, so as to carry off all the saline matter. As the quick- 
 silver which traces the images will not bear touching, the silvered plate should be 
 secured by a cover of glass, made tight at the edges by pasting paper round them. 
 
 In Jig. 25., which is a plan view of the iodine-box apparatus, c is an interior cover; 
 d is the iodine-dish ; e is the thin board to which the silvered plate is fixed, as 
 shown at Jig. 24. ; g is the cover of the box ; h h are small rods, at the four corners of 
 the inclined lining, k, of the box, to support the lid c ; j is a gauze of wire cloth cover, 
 to diffuse the iodine vapour ; k is the wooden lining, sloping like a hopper ; d d, in fig. 
 27., are buttons to fasten the board on the doors ; e shows the thickness of the frame ; 
 f is the silvered plate. In Jig. 35., a is the ground glass of the camera ; b is a mirror 
 inclined about 45° to the horizon, by means of the rod I. The image of the object is easily 
 brought into focus by moving forward or backward the sliding-box d, in laying hold of 
 it with both hands by the projections a, Jig. 28. When the focus is adjusted, the thumb- 
 screw, h, fixes the whole. The mirror is kept closed by two hooks at f, which take 
 into small eyes at g. The frame and ground glass plate are withdrawn and replaced 
 by the frame carrying the prepared plate, as represented in fig. 22., with the shading 
 doors, b, open in the camera. These doors and the sliding-box d are lined with black 
 velvet. The object glass is achromatic and periscopic, the concave being outside in the 
 camera; its diameter is about 3± inches, and focus about 13 inches. A diaphragm is 
 placed before the object glass, at 3| inches from it, and its aperture may be closed by a 
 plate moving in a pivot. This camera reverses the objects from left to right ; but this 
 may be obviated by placing a plane mirror on the outside beyond the aperture of the 
 diaphragm, as at J, fig 30., where it is fixed by means of a screw, k. Loss of light is 
 thereby occasioned. 
 
 Fig. 31. is an upright section, and fig. 32. a front elevation of the mercurial apparatus. 
 a the cover ; b the black board, with grooves to receive the board h ; c the cup of 
 quicksilver ; d, the spirit-lamp ; e, a small cock, through which the quicksilver may be 
 run off, if the apparatus be laid to one side ; /, the thermometer ; g, a glass window ; 
 h, the board bearing the metallic plate ; I, a stand for the spirit lamp, which is held by 
 the ring k, so that its flame may strike the bottom of the cup. The whole of the inside 
 of the apparatus should be blackened and varnished. 
 
 Fig. 33. is a front view of the washing apparatus made of tin plate, varnished. The 
 plates, to be washed, are laid on the angular ledge, d. e is a ledge to conduct the water 
 to the receptacle c. Fig. 34. is a side view of the washing apparatus. The patent was 
 enrolled in February, 1840. (See Newton's Journal, C. S. xvi. 1.) 
 
 Mr. Richard Beard having purchased from M. Daguerre a license to practise his 
 invention above described, received from a foreigner a communication of certain im- 
 
 K 2 
 
63 
 
 DAGUERROTYPE. 
 
 provements for which he obtained a patent in June, 1840. The first of these Is 
 the substitution of a concave reflecting mirror for the lens in the camera ob- 
 scura. Fig. 36. represents in section a slight wooden box, a a, open at the front, 
 opposite to the person sitting for the portrait. In the back part of the box a 
 concave mirror, b, is placed, to reflect the rays coming from the person. A small frame, 
 c, is fixed to an adjustable pedestal, d, which slides in grooves in the bottom of the box, 
 for the purpose of being set at the focal point of the mirror. In this frame, c, a polished 
 surface is first to be placed for trial, to receive the image correctly, as observed by the 
 operator, by looking through the opening, e, in the top of the box. The prepared 
 silvered plate is now substituted in the exact place for the trial one. The luminous 
 impression being made, the slide, d, is withdrawn, and the plate removed ; carefully 
 shut up in a box from the light. 
 
 The second object of this patent is making the prepared surface more uniform, by 
 passing two plates, with their silvered faces in contact, several times between hardened 
 rollers, annealing them at a low red heat after each passage. 
 
 His third object is to use a compound of bromine and iodine, instead of the latter 
 alone, for coating the silver ; which increases its sensibility to light, thereby shortening 
 and improving the operation of taking likenesses. He also recommends to use a com- 
 bination of iodine with nitric acid. Finally, Mr. Beard finds that by placing a screen 
 of any desired colour behind the sitter, the appearance of his Daguerrotype portrait is 
 improved. (Newton's Journal, xxiii. 112.) 
 
 M. A. J. F. Claudet, who had also purchased a license from M. Daguerre, obtained 
 a patent in December, 1841, for certain improvements upon the original process. His 
 first object is to give the front of the camera obscura such an aperture as to admit 
 the largest object glass intended to be used ; and of such he provides a series of dif- 
 ferent dimensions, each attached to its board, that may be fitted by a slide to the front 
 of the camera. 
 
 One of the greatest difficulties in the Daguerrotype process was the impossibility of 
 ascertaining the precise moment at which the light had produced, on the prepared 
 plate, the effect requisite for the vapour of mercury to bring out the image. By apply- 
 ing that vapour to the plate while the silver surface is being acted upon by the light, 
 the operator is enabled to see when his picture is complete. Another advantage of 
 this joint operation is, that the effect of the mercury upon those parts of the plate 
 which have been acted upon by the light, are more perfect when caused to take place 
 immediately under the luminous influence. Hence, instead of using the distinct box 
 with the cup of quicksilver, he places a cup containing that metal in the camera ob- 
 scura, with its spirit-lamp, and exhales the vapours there. When the mercury has 
 risen to the proper temperature, the aperture of the object-glass is thrown open, and 
 the light, reflected from the object to be delineated, is allowed to operate. 
 
 He watches the effect through an opening in the side of the camera, where he views 
 the prepared plate by the light of a lantern passing through a piece of red or orange- 
 coloured glass in the (other) side of the camera. Whenever the light and mercury, 
 by their simultaneous action, have produced a good image, the object-glass is covered, 
 and the silver plate, with its picture, removed, in order to be washed, and finished. 
 M. Claudet embellishes his Daguerrotype portraits by placing behind the sitter screens 
 of painted scenery, which furnish pleasing back grounds. He specifies also various 
 kinds of artificial illumination, to be used in the absence of solar light. (Newton's 
 Journal, C. S. xx. 430.) 
 
 According to M. Barnard, Daguerre's iodized plate should be exposed for half a 
 minute to the action of chlorine, mixed with a large proportion of common air ; 
 whereby it becomes so sensitive, that the pictorial impression is produced in the short 
 space of time necessary for removing and replacing the screen of the camera. The 
 mercury is afterwards employed ; as also the hyposulphite wash. Daguerrotype pic- 
 tures are coloured by dusting over them powders of proper hues, which are immediately 
 washed by passing the plate through water. What remains of the colour after this 
 ablution does not seem in the least to injure the appearance or alter the form of the 
 image. It would seem that those parts of the picture which were at first black, retain, 
 after being washed, a larger proportion of colouring matter than the lighter parts. 
 
 Several valuable improvements seem to have been made in Vienna upon the Da- 
 guerrotype process ; and among others, the mode of using chloriodine. 
 
 The best form of box for applying the chloriodic vapour is square, with its bottom of 
 plate glass, supported a little above the table by feet, a thumb-screw being one of 
 them, in order to give a certain inclination to the glass plate for spreading the 
 chloriodine over it uniformly. A sheet of white paper being laid beneath the box, 
 enables the operator to see whether the liquid chloriodine is properly distributed. 
 There is a groove round the top of the box, into which the ledge of the lid fits tight. 
 A thermometer is placed in the box. 
 
DAGUERROTYPE. 
 
 69 
 
 Voigtland's lenses consist of two achromatic object glasses placed apart ; the first 
 nearest the object, having an aperture of 18 lines; the second one of 19 lines; the 
 solar focus of the two is 5| inches. A system of lenses of so short a focus with so large 
 apertures affords from 11 to 12 times more illumination than Daguerre's original 
 apparatus did. The finest portraits can be produced in the course of from 10 to 30 
 seconds with this arrangement. Such an apparatus, elegantly made in brass, costs oidy 
 120 gulden, or about 10 guineas. 
 
 Voigtland has recently made a camera with two object glasses, as above arranged, 
 each having an aperture of 37 lines, and a combined focus of 1 2 inches. By means of 
 this instrument, portraits 5| inches in size can be made. The landscapes produced in 
 them are very beautiful. Its price is 144 gulden, about 12 guineas. Along with the 
 above apparatus, a box with a bottom of amalgamated copper is used for applying the 
 vapour of mercury. 
 
 By peculiar methods of polishing the silvered copper plate peculiar tones and tints 
 may be given to the picture. The olive oil and pumice powder are indispensable for 
 removing the scratches from the plate and to render its surface uniform. If a delicate 
 blue tone be desired, the plate should be a second time polished with sulphuric ether 
 and washed tripoli ; and a third time with dilute nitric acid and Paris red, rubbing 
 the plate lastly with a piece of washleather and crocus. But if a brownish black tone 
 be wished for, a like series of operations is to be gone through, only instead of the 
 ether and tripoli, spirit of ammonia and Vienna lime is to be \ised. 
 
 To give the plate the utmost sensibility to light, a film of iodine should be given in 
 the first place. If with dry iodine, this should be strewed, then covered with cotton, 
 and lastly with a sheet of paper, and the plate above the last, but not so as to touch it. 
 This may be done also with a solution of 1 part of iodine in 6 of spirits of wine, put 
 into a saucer, which is laid on the bottom of the box and covered with gauze. The 
 plate is to be removed whenever it has acquired a faint brazen tint. By this means the 
 plate receives the impressions of light so well as to produce good contrasts between the 
 white and the dark places. The application of bromine afterwards causes a rapid 
 reception of the image, and occasions the deep black shades of an object. The best 
 form is brome water, made by dissolving the bromine in a little distilled water, and then 
 adding more, when it is wanted, till the solution acquires a straw yellow colour. A 
 delicate thermometer being put into the box, the solution is to be spread uniformly on 
 its glass bottom, the plate being laid on above and covered up, while the time of exposure 
 must be counted by seconds, with a clock or watch. If the temperature be 
 41° F. the time should be 258 seconds. 
 
 50° 230 — 
 
 590 , 201 — 
 
 68° 158 — 
 
 77° 113 — 
 
 By attending to these instructions exact results may always be obtained. 
 A second mode of experimenting is with bromiodine ; prepared by dissolving 1 part 
 of bromine in an alcoholic solution of 5 parts of iodine ; and diluting this mixture with 
 water, till it acquires the colour of Bavarian beer. The action of this application upon 
 the plate is so rapid as hardly to leave time for consideration. It must be watched 
 every instant till the dark gold yellow tint appear; when it is ready for the camera. 
 
 The best time of day for Daguerrotype operations is from an hour after the sun rises 
 till he comes within 45° of the meridian, and not again till he has passed the meridian 
 by 45°. When the sitting is too long, the parts which should be pure white become 
 of a dirty blue tint, and the dark parts become brown. The picture is burnt, so to 
 speak. 
 
 Chloride of gold applied to the picture has the effect of fixing and enlivening the 
 tints. A small grate being fixed by a clamp to the edge of a table, the plate is laid 
 upon it with the image uppermost, and overspread evenly with solution of chloride of 
 gold, by means of a fine broad camel hair brush, without letting any drop over the 
 edge. A spirit lamp is now brought under the plate, and moved to and fro till a 
 number of small steam bubbles appear upon the image. The spirit lamp must be 
 immediately withdrawn. The remainder of the chloride solution must be poured back 
 into the phial, to be used on another occasion. It is lastly to be washed and examined. 
 This operation has been repeated three or four times with the happiest effect, of giving 
 fixity and force to the picture. It may then be wiped with cotton without injury. 
 
 By dusting various pigment powders from small cotton wool dossils upon the picture, 
 previously coated with an alcoholic solution of copal, and nearly dry, the appearance of 
 a coloured miniature has been very successfully imitated. The varnish must be 
 applied delicately with one stroke of a broad brush of badger hair.* 
 
 * See Praktische Anweisung zum Daguerrotypiren, Leipzig. &c. 1843. 
 
70 
 
 ELECTRO-METALLURGY. 
 
 DEXTRINE. This substance has exactly the same chemical composition as 
 starch, consisting of 24 atoms of carbon, 20 of hydrogen, and 10 of oxygen (Dumas); 
 but it is distinguished from starch by its solubility in cold water, like gum, and not 
 being affected by iodine. British gum, as it is called, or roasted starch, is merely 
 dextrine somewhat discoloured ; a substance apparently used for the paste on the 
 Queen's head post-office letter stamps. A process discovered by M. Payen, and 
 patented in France by M. Henze, for making dextrine, consists in moistening one ton 
 of dry starch with water containing 4i lbs. of strong nitric acid. The starch thus 
 uniformly wetted, is made up into small bricks or loaves, and dried in a stove. It is 
 then rubbed down into a coarse powder, and exposed in a stove-room to a stream of 
 air heated to about 160° F. Being now triturated, sifted, and heated in a stove to 
 about 228° F., it forms a perfect dextrine of a fair colour; because the acid acts 
 as a substitute for the higher heat, used in making the British gum. Such an 
 article makes a fine dressing for muslin and silk goods, and is much employed in 
 French surgery, for making a stiff paste-support to the bandages of fractured limbs, 
 DISTILLATION. Fig. 38. represents one form of the worm-safe, which is a con- 
 trivance for permitting the distiller to 
 observe and note at any period of the 
 distillation the alcoholic strength or the 
 specific gravity of his spirits, without 
 access to the still or the means of pur- 
 loining the product before it has paid duty. 
 The nose-pipe of the worm tub terminates 
 in, and is firmly cemented to the side of the 
 glass globe, a, from whose bottom the dis- 
 charge pipe descends vertically, but has a 
 stop-cock upon it, and a branch small pipe 
 
 b, turned up parallel to the former. This 
 branch is surmounted with a glass cylinder, 
 
 c, which, when the stop-cock is opened, gets 
 filled with the spirits, and then receives a 
 hydrometer to show the gravity of the 
 fluid. The stop-cock mechanism is so 
 contrived, that only one full of the small 
 glass cylinder can be obtained at a time. 
 
 The following is the gross produce of 
 the Excise duties on British distilled 
 spirits for the United Kingdom annually, 
 from 1830 to 1840 inclusive: — 1831, 
 5,196,175/.; 1832, 5,163,373/.; 1833, 
 5,258,5721. ; 1834, ; 5,287,032 ; 1835, 
 5,073,276/.; 1836, 5,485,883/.; 1837, 5,006,697/.; 1838, 5,451,792/.; 1839, 
 5,363,220/.; 1840, 5,208,040/. The net produce is very nearly the same. In 1838, 
 26,486,543 millions of gallons paid duty ; in 1839, 25,190,843 ; and in 1840, 21,859,337. 
 See Rum, Spirits, and Still. 
 
 E. 
 
 ELECTRO-METALLURGY. By this elegant art perfectly exact copies of any 
 object can be made in copper, silver, gold, and some other metals, through the agency 
 of voltaic electricity. The earliest application of this kind, seems to have been prac- 
 tised about ten years ago, by Mr. Bessemer, of Camden Town, London, who deposited 
 a coating of copper on lead castings, so as to produce antique heads in relief, about 3 
 or 4 inches in size. He contented himself with forming a few such ornaments for his 
 mantelpiece ; and though he made no secret of his purpose, he published nothing upon 
 the subject. A letter of the 22d of May, 1839, written by Mr. J. C. Jordan, which ap- 
 peared in the Mechanics' Mag. for June 8, following, contains the first printed notice of the 
 manipulation requisite for obtaining electro-metallic casts ; and to this gentleman, there- 
 fore, the world is indebted for the first discovery of this new and important application 
 of science to the uses of life. It appears that Mr. Jordan had made his experiments in 
 the preceding summer, and having become otherwise busily occupied, did not think of 
 publishing till he observed a vague statement in the Journals, that Professor Jacobi, of 
 St. Petersburg, had done something of the same kind. Mr. Jordan's apparatus consisted 
 of a glass tube closed at one extremity with a plug of plaster of Paris, and nearly filled 
 with a solution of sulphate of copper. This tube, and its contents, were immersed in 
 
ELECTRO- METALLURGY. 
 
 71 
 
 a solution of common salt. A plate of copper was plunged in the cupreous solution, 
 and was connected by means of a wire and solder, with a zinc plate dipped in the 
 brine. A slow electric action was thus established through the moist plaster, and 
 copper was deposited on the metal in a thin plate, corresponding to the former in 
 smoothness and polish ; so that when he used an engraved metal matrix, he" obtained 
 an impression of it by this electric agency. " On detaching the precipitated metal," 
 says he, " the most delicate and superficial markings, from the fine particles of powder 
 used in polishing to the deeper touches of a needle or graver, exhibited their corre- 
 spondent impressions in relief with great fidelity. It is, therefore, evident that this 
 principle will admit of improvement, and that casts and moulds may be obtained 
 from any form of copper. This rendered it probable that impressions might be obtained 
 from those other metals having an electro-negative relation to the zinc plate of the 
 battery. With this view a common printing type was substituted for the copper-plate, 
 and treated in the same manner. This, also, was successful ; the reduced copper 
 coated that portion of the type immersed in the solution. This, when removed, was 
 found to be a perfect matrix, and might be employed for the purpose of casting, where 
 time is not an object." " Casts may probably be obtained from a plaster surface sur- 
 rounding a plate of copper, &c." 
 
 On the 12th of September following the above publication, Mr. Thomas Spencer 
 read a Paper " On Voltaic Electricity applied to the purpose of working in Metal," 
 before the Polytechnic Society of Liverpool ; which he had intended to present to the 
 British Association at Birmingham in the preceding August, but not being well 
 received there, he exhibited merely some electro- metallic casts which he had prepared. 
 The Society published Mr. Spencer's Paper, and thereby served to give rapid diffusion 
 to the practice of electro-metallurgy. 
 
 One of the most successful cultivators of this art has been Mr. C. V. Walker, 
 Secretary to the London Electrical Society. He has published an ingenious little 
 work in two parts, entitled Electrotype Manipulation, where he presents, in a lucid 
 manner, the theory and practice of working in metals, by precipitating them from their 
 solutions through the agency of voltaic electricity. His first part is devoted to the 
 explanation of principles, to the preparation of moulds, to the description of the voltaic 
 apparatus to be used, to bronzing, to coating busts with copper, to the multiplication 
 of engraved plates, and to the deposition of other metals. 
 
 Fig. 39. represents a single cell voltaic apparatus for electro-metallurgy. z is 
 a rod of amalgamated zinc, to is the mould on which the metal 
 is to be deposited ; w, is the wire joining them ; c, is a strong 
 solution of sulphate of copper in the large vessel ; p, is a tube 
 or cylinder of porous earthenware, standing in the other, and 
 containing dilute sulphuric acid. The solution of blue vitriol is 
 kept saturated, during the progress of its depositing copper, by 
 piling crystals of the salt upon the shelf, shown by the dots under p. 
 The mould to be coated should not be too small in reference to 
 the surface of zinc under voltaic action. The time for the depo- 
 sition to be effected depends upon the temperature ; and is less the 
 higher this is within certain limits ; and at a freezing temperature 
 it ceases almost entirely. When a mould of fusible metal is used, 
 it should not be placed in the voltaic apparatus till every thing 
 is arranged, otherwise oxide will be deposited upon it, and spoil 
 the effect. When the circuit is completed the mould may be im- 
 mersed, but not before. Wax moulds are rendered electric con- 
 ductors, and thereby depositors as follows : — After breathing on 
 the wax, rub its surface with a soft brush dipped in plumbago ; breathing and 
 rubbing alternately till the surface be uniformly covered. Attach a clean wire 
 to the back of the mould, connecting it by plumbago with the blackened wax. 
 Sealing-wax is coated in like manner. Casts of Paris plaster are first well im- 
 bued with melted wax or tallow, and then black-leaded. Objects in Paris plaster 
 should be thoroughly penetrated with hot water, but not wet on the surface, 
 before wax casts are made from them. Moulds are best taken from medals in stearine 
 (stearic acid). For plating and gilding by electro -chemical agency, the following 
 simple plan of apparatus is used. Fig. 40. is a rectangular porcelain vessel, which 
 contains in its centre a porous cell for containing the solution of oxide of silver or 
 gold, by means of cyanide of potassium ; and this porous cell is surrounded at a little 
 distance by a similarly formed vessel of zinc. The connection is formed between the 
 zinc and the suspended object to be coated, either by a pinching screw, or by the 
 pressure of its weight upon the wire. The dilute acid which excites the zinc should, 
 in this case, be very weak, in reference to the strength of the cyanide solution, which 
 should be recruited occasionally by the addition of oxide. 
 
72 
 
 ELECTRO-METALLURGY. 
 
 It has been found that with cyanide solutions of gold and silver in the electro- 
 chemical apparatus, the nascent cyanogen at the positive pole or plate, in a decom- 
 position cell, will act upon and dissolve gold and silver. Two or three of Daniell's 
 cylindric cells, as shown at a in fig. 41., of a pint size, for acting upon solutions of 
 
 gold or silver, will in general suffice. The decomposition cell b is made of glass or 
 porcelain. The zinc may be amalgamated, and excited with brine ; the copper cell 
 contains, as usual, a solution of blue vitriol. To the end of the wire attached to the 
 copper cylinder of the battery, a plate of silver or gold is affixed ; and to the end of 
 the wire attached to the zinc cylinder is affixed the mould, or surface, to be plated or gilt. 
 The plates of silver or gold and zinc should be placed face to face as shown in the figure 
 in the decomposition cell ; which is filled by the cyanide solution. A certain degree 
 of heat favours the processes of electro-gilding and plating. The surface is dead as 
 first obtained, but it may be easily polished with leather and plate-powder, and bur- 
 nished in whole or in parts with a steel or agate tool. 
 
 In March, 1840, Messrs. Elkington obtained a patent for the use of prussiate of 
 potash, as a solvent for the oxides of gold and silver in the electro-chemical apparatus 
 for plating and gilding metals. They also " sometimes employ a solution of protoxide 
 (purple of Cassius) in the muriates of potash, &c." The chemical misnomers, in their 
 specification, are very remarkable, and do great discredit to the person employed to 
 draw it up. Prussiate of potash is the ordinary commercial name of a salt very different 
 
 from the cyanide of potassium, — the substance really meant by the patentees and 
 
 the purple of Cassius, is very different from protoxide of gold. 
 
 In plating or gilding great care must be bestowed in making the articles clean, bright, 
 and perfectly free from the least film of grease. For this purpose, they should be 
 boiled in a solution of caustic alkali, then scoured with sand and water, next dipped 
 into a dilute acid, and finally rinsed with water. A solution of the nitrate or cyanide 
 of mercury may also be used with advantage for cleaning surfaces. The following 
 metals have been deposited by electro-chemistry : — 
 
 Gold, platinum, silver, copper, zinc, nickel, antimony, bismuth, cobalt, palladium, 
 cadmium, lead, and tin ; of these, the first five are the most important and valuable. 
 The gilding solution may be prepared by placing slips or sheets of gold in a solution 
 of cyanide of potassium, and attaching to the negative pole of a voltaic battery, a small 
 plate of gold, but to the positive pole a much larger one ; whereby the latter com- 
 bines with the cyanogen, under the influence of positive electricity, and forms a 
 solution. Or, oxide of gold, precipitated from the chloride by magnesia, may be dis- 
 solved in the solution of the cyanide. 
 
 For making copper medals, &c, a plate of amalgamated zinc is to be put into a 
 vessel of unglazed earthenware, or of any other porous substance, filled with dilute sul- 
 phuric acid ; which vessel is set into a trough of glass, glazed pottery, or pitched wood, 
 containing blue vitriol in the state of solution, as well as in the state of crystals upon a 
 perforated shelf, near the surface of the liquid. 
 
 The moulds to be covered with copper are to be attached by a copper wire to the 
 zinc plate. The surface of zinc excited by the acid should be equal to that of the 
 moulds ; with which view a piece of zinc, equivalent in size to the mould, should be 
 suspended in front of it. 
 
 For depositing copper upon iron, Messrs. Elkington use a solution of ferrocyanide 
 of copper in cyanide of potassium in the decomposition trough, instead of sulphate of 
 copper, neutralized from time to time with a little caustic alkali, as in the common 
 
• ELECTRO-METALLURGl. 
 
 73 
 
 practice of making medals, &c, of copper. I should imagine that the black oxide of 
 oopper dissolved in solution of cyanide of potassium would answer better ; as the iron 
 in the ferrocyanide might be rather injurious. The iron to be coppered being pre- 
 viously well cleaned from rust, &c, with the aid of a dilute acid, is to be plunged into 
 the cyanide solution heated to 1 20° Fahrenheit, and connected by a wire with the 
 negative pole of a voltaic battery, as formerly described. In from five to ten minutes, 
 the iron will be completely coated. It is then to be scoured with sand, and plunged 
 into solution of sulphate of copper ; whereby it will show black spots wherever there 
 are any defective places. In this case, it is to be cleaned and replaced under the cy- 
 anide solution, in the decomposition cell for a minute or two. Zinc may be deposited 
 from a solution of its sulphate by a like arrangement. 
 
 Metallic cloth may be made as follows : — On a plate of copper attach quite 
 smoothly a stout linen, cotton, or woollen cloth, and connect the plate, with the nega- 
 tive pole of a voltaic battery ; then immerse it in a solution of copper or other metal, 
 connecting a piece of the same metal as that in the solution with the positive pole ; 
 decomposition takes place, and the separated metallic particles in their progress 
 towards the metal plate or negative pole, insinuate themselves into the pores of the 
 tissue, and form a complete sheet of flexible metal. Lace is metallised by coating it 
 with plumbago, and then subjecting it to the electro-metallurgic process. 
 
 The gilding solution should be used in the electric process at a temperature of 
 130° F. The more intense the electric power, the denser and harder is the metallic 
 coat deposited. 
 
 Metallic silver may be combined with cyanogen by subjecting it to the joint action 
 of a solution of cyanide of potassium and positive electricity. Or cyanide of silver 
 may be precipitated from the nitrate by a little cyanide of potassium, and afterwards 
 dissolved by means of an excess of cyanide of potassium. The quantity of electric 
 power or surface-size of the battery should in all cases be proportioned to the surface 
 of the articles to be plated or gilt, and the electric intensity or number of sets of jars 
 proportioned to the density of the solution. Plating is accomplished in from 4 to 6 
 hqurs. The articles should be weighed before and after this operation, to ascertain 
 how much silver they have taken on. 
 
 Messrs. Elkington make their moulds with wax, combined with a little phosphorus, 
 which reduces upon their surfaces a thin film of gold or silver, from solutions of these 
 metals, which films are better than the blackleaded surfaces for receiving the copper 
 deposit. They also recommend to add a little alkali to the solution of sulphate of 
 copper, intended to afford a deposit of metal. The single cell, first described above, 
 is best adapted for this purpose. 
 
 M. Ruolz employs for gilding, a solution of sulphuret of gold in sulphuret of potas- 
 sium, which he prepares by precipitating a solution of gold in aqua regia, by sulphu- 
 retted hydrogen, and re-dissolving the precipitate with sulphuret of potassium. By 
 the use of this solution of gold, he obtains a very beautiful and solid gilding, and at 
 less expense than with cyanide of potassium. Every metal which is a negative elec- 
 trode to gold may be gilded. 
 
 Platinizing is effected best by means of a solution of the potash-chloride of platinum 
 in caustic potash. 1 milligramme (0-015 grain) covers completely a surface of 50 
 square centimetres (2 inches square) ; the film of platinum is only one hundredth of a 
 milligramme thick. 
 
 M. Boettger has shown that we may easily tin copper and brass in the moist way by 
 dissolving peroxide of tin (putty) in hydrate of potash (caustic potash ley), putting at 
 the bottom of the vessel holding that solution some turnings of tin, setting the piece 
 of copper or brass upon the turnings, and making the liquor boil. An electric current 
 is produced by the contact of the dissimilar metals; and as the tin is withdrawn by 
 the copper or brass from the solution, it is restored to it by the turnings. Zinking 
 may be done in the same way ; by putting pieces of zinc into a concentrated solution 
 of chlorine, by setting the piece of metal to be zinked in contact with these pieces, and 
 applying heat to the vessel containing the whole. 
 
 For certain new methods of constructing and arranging voltaic batteries for electro- 
 metallurgic operations, a patent was obtained by Dr. Leeson in June 1 842. 
 
 Fig. 42. is a longitudinal section of the battery, and Jig. 43. a plan view of the frame 
 to which the metal plates are attached, a is a rectangular wooden trough, containing 
 a wooden frame b, formed with vertical grooves in its sides, to receive a series of porous 
 cells c, c, c. The plates of the battery are suspended in the fluid or fluids by brass 
 forks d, d, fastened to a wooden frame e, e, which rests upon the trough «, and is con- 
 nected to the other frame b, by two pins /, when they are required to be raised together 
 out of the trough a, a. 
 
 The battery mav be charged as usual with one or two fluids ; one of them in the latter 
 
 L 
 
74 
 
 ELEMENTS, CHEMICAL. 
 
 case being contained in the porous cells c, c, c ; and plates of copper and zinc, or any 
 other suitable metals, may be employed. 
 
 The second improvement consists in cleaning copper and zinc plates after they have 
 been used in a battery, by the employment of a voltaic battery ; and also in amalga- 
 mating or coating with mercury the surfaces of zinc plates, by the same means to render 
 them suitable for being used in the construction of the voltaic apparatus. 
 
 The third improvement consists in exciting electricity by a combination of nitric, 
 sulphuric, or muriatic acid, with any of the following substances ; viz. impure ammoniaeal 
 or lime liquor of the gas works, solutions of alkaline and earthy sulphurets, the alkalies 
 and their carbonates, or lastly the acidulous sulphate of iron generated from iron 
 pyrites. 
 
 43 
 
 
 
 
 
 
 r 
 
 
 liliiji;! 
 
 
 ~1§~ 
 
 
 
 :i e ji 
 w. • 4 - 
 
 
 
 Another of Dr. Leeson's manifold improvements is for depositing metallic alloys, 
 consists in the employment of one battery, with the " alternating cathode," represented 
 in fig. 44. It is composed of a beam, a, mounted on the shaft, b, which turns in bear- 
 ings carried by standards, c ; the beam communicates with the anode of the battery by 
 the wire, d, and a vibrating motion is given to it by the rod, e, from the shaft, /, which 
 is driven by an electro-magnetic engine, or any other suitable prime mover, g, g are 
 two vessels containing mercury, connected by wires, h, h, with the cathode plates of the 
 two metals composing the alloy (but if the alloy is to consist of more than two metals, 
 then more vessels, g, will be required, one for each cathode plate) ; these plates are 
 immersed in a solution composed of similar salts of the different metals to be deposited, 
 together with the anode, or surface to be deposited upon, which is connected by a wire 
 with the cathode of the battery. A communication is established between the two 
 cathode plates, or supply metals, and the anode of the battery, by means of the rods, i, i, 
 which are caused, by the vibration of the beam, a, to dip alternately into either the one 
 or the other of the vessels, g ; and thus each metal will be deposited on the article to 
 be coated, during the time that the connection is established between it and the battery, 
 by the immersion of its rod into the vessel of mercury. The relative proportions of 
 the two metals is adjusted by lengthening or shortening the rods, i, i, as shown in the 
 figure, so that they may be immersed for a longer or shorter period in the mercury. 
 
 Where the electrical current enters the electrolyte, is the anode ; where it leaves it, is 
 the cathode. 
 
 The patentee describes ten other improvements, which seem to be ingenious. See 
 Newton's Journal, xxii. 292. 
 
 ELEMENTS, CHEMICAL The catalogue given in the Dictionary has been 
 augmented by four new bodies \ Lanthanium, Didymium, from Cerium ; Erbium and 
 Terbium, from Yttria. 
 
ENAMELLING. 
 
 75 
 
 EL VAN. The name given by the Cornish miners to porphyry, as also to the 
 heterogeneous rocky masses which cccur in the granite or in the clay slate, deranging 
 the direction of their metallic veins, or . even the mineral strata : but elvan generally 
 indicates a felspar porphyry. 
 
 EMBOSSING OF LEATHER. Beautiful ornaments in basso-relievo for deco- 
 rating the exteriors or interiors of buildings, medallions, picture-frames, cabinet work, 
 &c, have been recently made by the pressure of metallic blocks and dies, for which 
 invention a patent was obtained in June, 1839, by M. Claude Schroth. The dies are made 
 of type metal, or of the fusible alloy with bismuth, called d'Arcet's. The leather is 
 beaten soft in water, then wrung, pressed, rolled, and fulled as it were, by working 
 it with the hands till it becomes thicker and quite supple. In this state it is laid on 
 the mould, and forced into all its cavities by means of a wooden, bone, or copper tool. 
 In other cases, the embossing is performed by the force of a press. The leather, when 
 it has become dry, is easily taken off the mould, however deeply it may be inserted 
 into its crevices, by virtue of its elasticity. A full detail of all the processes is given 
 in Newton's Journal, vol. xxii. p. 122. 
 
 ENAMELLING of Cast Iron and other Hollow Ware for Saucepans, ^c. In Decem- 
 ber, 1799, a patent was obtained for this process by Dr. Samuel Sandy Hickling. His 
 specification is subdivided into two parts : — 
 
 L The coating or lining of iron vessels, &c. by fusion with a vitri liable mixture, 
 composed of 6 parts of calcined flints, 2 parts of composition or Cornish stone, 9 parts of 
 litharge, 6 parts of borax, 1 part of argillaceous earth, 1 part of nitre, 6 parts of calx of 
 tin, and 1 part of purified potash. Or, 2dly, 
 
 8 parts of calcined flints, 8 red lead, 6 borax, 5 calx of tin, and 1 of nitre. Or, 3dly, 
 
 12 of potter's composition, 8 borax, 10 white lead, 2 nitre, 1 white marble calcined, 
 1 argillaceous earth, 2 purified potash, and 5 of calx of tin. Or, 4thly, 
 
 4 parts calcined flint, 1 potter's composition. 2 nitre, 8 borax, 1 white marble cal- 
 cined, ^ argillaceous earth, and 2 calx of tin. 
 
 Whichever of the above compositions is taken, must be finely powdered, mixed, fused ; 
 the vitreous mass is to be ground when cold, sifted, and levigated with water. It is then 
 made into a pap with water or gum water. This pap is smeared or brushed over the 
 anterior of the vessel, dried, and fused with a proper heat in a muffle. 
 
 Calcined bones are also proposed as an ingredient of the flux. 
 
 The fusibility of the vitreous compounds is to vary according to the heat to be 
 applied to the vessel, by using various proportions of the siliceous and fluxing 
 materials. Colours may be given, and also gilding. 
 
 The second part or process in his specification describes certain alloys of iron and 
 nickel, which he casts into vessels, and lines or coats them with copper precipitated 
 from its saline solutions. It also describes a mode of giving the precipitated copper a 
 brassy surface by acting upon it with an amalgam of zinc with the aid of heat. 
 
 A factory of such enamelled hollow wares was carried on for some time, but it was 
 given up for want of due encouragement. 
 
 A patent was granted to Thomas and Charles Clarke on the 25th of May, 1839, for 
 a method of enamelling or coating the internal surfaces of iron pots and saucepans, in 
 such a way as shall prevent the enamel from cracking or splitting off from the effects 
 of fire. This specification prescribes the vessel to be first cleaned by exposing it to the 
 action of dilute sulphuric acid (sensibly sour to the taste) for three or four hours, 
 then boiling the vessel in pure water for a short time, and next applying the composition. 
 This consists of 100 lbs. of calcined ground flints ; 50 lbs. of borax calcined, and finely 
 ground with the above. That mixture is to be fused and gradually cooled. 
 
 40 lbs. weight of the above product is to be taken with 5 lbs. weight of potter's clay; 
 to be ground together in water Until the mixture forms a pasty consistenced mass, 
 which will leave or form a coat on the inner surface of the vessel about one-sixth of an 
 inch thick. When this coat is set, by placing the vessel in a warm room, the second 
 composition is to be applied. This consists of 125 lbs. of white glass (without lead), 
 25 lbs. of borax, 20 lbs. of soda (crystals), all pulverized together and vitrified by 
 fusion, then ground, cooled in water, and dried. To 45 lbs. of that mixture, 1 lb. of 
 soda is to be added, the whole mixed together in hot water, and when dry pounded ; 
 then sifted finely and evenly over the internal surface of the vessel previously covered 
 with the first coating or composition, whilst this is still moist. This is the glazing. 
 The vessel thus prepared is to be put into a stove, and dried at the temperature of 
 212° F. It is then heated in a kiln or muffle like that used for glazing china. The 
 kiln being brought to its full heat, the vessel is placed first at its mouth to heat it 
 gradually, and then put into the interior for fusion of the glaze. In practice it has 
 been found advantageous also to dust the glaze powder over the fused glaze, and apply 
 a second fluxing heat in the oven. The enamel, by this double application, becomes 
 much smoother and sounder. 
 
 L 2 
 
76 EVAPORATION. 
 
 Messrs. Kenrick of West Bromwich having produced in their factory and sent intj 
 the market some excellent specimens of enamelled saucepans of cast iron, were sued hy 
 Messrs. Clarke for an invasion of their patent rights ; but after a long litigation in 
 Chancery the patentees were nonsuited in the Court of Exchequer. The previous process 
 of cleansing with dilute sulphuric acid appeared by the evidence on the trial to have been 
 given up by the patentees, and it was also shown by their own principal scientific 
 witness that a good enamelled iron saucepan could be made by Hickling's specification. 
 In fact, the formulae by which a good enamel may be compounded are almost innu- 
 merable ; so that a patent for such a purpose seems to be untenable, or at least most 
 easily evaded. I have exposed the finely enamelled saucepans of Messrs. Kenrick to 
 very severe trials, having fused even chloride of calcium in them, and have found them 
 to stand the fire very perfectly without chipping or cracking. I consider such a 
 manufacture to be one of the greatest improvements recently introduced into domestic 
 economy ; such vessels being remarkably clean, salubrious, and adapted to the most 
 delicate culinary operations of boiling, stewing, making of jellies, preserves, &c. 
 They are also admirably fitted for preparing pharmaceutical decoctions, and ordinary 
 extracts. 
 
 The enamel of the said saucepans is quite free from lead, in consequence of the 
 glass which enters into its composition being quite free from that metal. In several 
 of the saucepans which were at first sent into the market by Messrs. Clarke, their enamel 
 was found on analysis by several chemists to contain a notable proportion of oxide of lead. 
 In consequence of the quantity of borax and soda in the glaze, this oxide was so readily 
 acted upon by acids that sugar of lead was formed by digesting vinegar in them with a 
 gentle heat. The presence of this noxious metal formed, in my opinion, a legitimate 
 ground for contesting the patent, being in direct violation of the terms of the specifica- 
 tion. Messrs. Kenrick's wares have been always free from this deleterious metal. Messrs. 
 Clarke, I understand, have for some time been careful to reject from their enamel-com- 
 position all glass which contains lead ; ■ and they now manufacture also whole'.ome 
 enamelled ware. Thus the public have profited in a most important point by the 
 aforesaid litigation. 
 
 Enamelled iron saucepans had been many years ago imported from Germany, and 
 sold in London. I had occasion to analyse their enamel, and found to my surprise 
 that it contains abundance of litharge or oxide of lead. The Prussian government has 
 issued an edict prohibiting the use of lead in the enamelling of saucepans, which are so 
 extensive^ manufactured in Peiz, Gleiwitz, &c. Probably the German ware sent to 
 England was fabricated for exportation, with an enamel made to flux easily by a dose 
 of litharge. The composition of the said enamel is nearly the same with that which I 
 found upon some of the earlier saucepans of Messrs. Ckrke. Had their patent been 
 sustained, the important legal question would have arisen, whether it gave the patentees 
 the power of preventing dealers from continuing to sell what they had been habitually 
 doing for a great many years. 
 
 A suitable oven or muffle for lining or coating metals with enamel may have the 
 following dimensions : — 
 
 The outside, 8 feet square, with 14-inch walls; the interior muffle, 4 feet square at 
 bottom, rising 6 inches at the sides, and then arched over ; the crown may be 18 inches 
 high from the floor ; the muffle should be built of fire-brick, 21 inches thick. Another 
 arch is turned over the first one, which second arch is 7 inches wider at the bottom, 
 and 4 inches higher at the top. A 9-inch wall under the bottom of the muffle at its 
 centre divides the fire-places into two, of 16 inches width each, and 3 feet 8 inches 
 long. The flame of the fire plays between the two arches and up through a 3-inch flue 
 in front, and issues from the top of the arch through three holes, about 4 inches 
 square. These open into a flue, 10x9 inches, which runs into the chimney. 
 
 The materials for the enamel body (ground flint, potter's clay, and borax) are first 
 mixed together and then put into a reverberatory furnace, 6 feet 6 inches long, by 
 3 feet 4 wide, and 12 inches high. The flame from an 18-inch fireplace passes over 
 the hearth. The materials are spread over the floor of the oven, about 6 inches thick, 
 and ignited or fritted for four or five hours, until they begin to heave and work like 
 yeast, when another coating is put on the top, also 6 inches thick, and fired again, and 
 so on the whole day. If it be fired too much, it becomes hard and too refractory to 
 work in the muffles. The glaze is worked in an oven similar to the above. It may 
 be composed of about one half borax and one half of Cornish stone in a yellowish 
 powder procured from the potteries. This is fritted for 10 hours, and then fused into 
 a glass which is ground up for the glaze. 
 
 EVAPORATION. For the following scheme of generating, purifying, and con- 
 densing steam, Mr. Charles Clark, merchant, London, obtained a patent in January, 
 1843. His apparatus for converting sea- water, &c, economically into good fresh 
 water, is represented in Jigs. 46. 47, 48. A is the supply cistern, which communicates 
 
EVAPORATION. 
 
 77 
 
 with a pipe a, with a self-regulating eduction apparatus B. C is a strong wrought 
 iron cylinder, fitted at bottom into a flanged ring- place, c, and covered with a conical 
 
 VTT7 
 
 top ; it is about two thirds filled with the water, to be operated upon. D is a cylin- 
 drical furnace concentric with the water cylinder C ; d is an upwards air and water- 
 tight tube, which serves both as a feed-pipe, through which the fuel is supplied to the 
 furnace, and as a passage for the escape of the smoke, and other gaseous products of 
 combustion ; e is a hinged trap-door through which the fuel is passed into the tube d; 
 h is a chimney into which the pipe d terminates ; and i, a damper, by which the degree 
 of activity given to the furnace can be regulated at pleasure ; f is an open air-pipe, 
 which leads from the outside, through the boiler into the furnace, a little way above 
 the fire-bars, and assists in securing a good draught through the furnace into the 
 chimney. To the water cylinder C there are attached gauge-cocks, g g, for ascertaining 
 from time to time the height of the water ; I is a cock or tap for drawing off the 
 brine, and other residual matters which collect at the bottom of the boiler ; m is a 
 screw-cap and hole, through which access may be had to the interior of the water 
 cylinder C, when it needs to be cleaned ; E is a short pipe fitted into the conical top 
 of the water cylinder C, which conveys the steam generated in it, into the steam-head 
 or receiver F; G is a concave plate, resting upon the top of the pipe E, a little larger 
 than that pipe, and kept steady by a weight, k, of one or more pounds, suspended from 
 it by wires. This plate prevents, in a great measure, the escape water escaping into 
 the steam-head (an accident commonly called priming in steam engines ; because, till 
 the steam has acquired a pressure exceeding that of the counterweight k, it cannot 
 
78 EVAPORATION. 
 
 raise the weight G, so as to escape freely into the steam-head F, since any particle of 
 water must, during the rising of the cap G, strike against it, and drop hack, either into 
 the water cylinder C, through the pipe E, or into the space round that pipe at the 
 bottom of the steam-head F ; whence it may be withdrawn by the cock shown in the 
 drawing. H is a pipe which conveys the steam from the steam-head F to the rectifier 
 R. This consists simply of a cylinder (about one third the size of the cylinder C) 
 laid horizontally, in the lower part of which a body of water speedily collects, and 
 serves to retain any particle of undecomposed matter, which may come over with the 
 steam, as it continues to flow in from the boiler ; whereby only its purer portions may 
 pass off from the rectifier R, by the pipe N. n is a cock or tap, at the botom of the 
 cylinder R for drawing off its water occasionally; R 1 is a second steam-rectifier, like 
 R, into which the steam passes from the pipe N, and is thereby still further purified ; 
 but when the proportion of saline matter is small, R' may be dispensed with, and for 
 very foul water, two or three more such rectifiers may be added. 
 
 The condenser for liquefying the purified steam, and aerating the resulting water, 
 is shown at t x , t% t 3 . It is composed of conical upright compartments communicating 
 with each other; the chamber t ] is surrounded by the water in the cistern A (slightly 
 heated by the steam in that chamber), while the chambers & and t 3 are exposed freely 
 to the air. The lowest of these, t 3 , terminates at bottom in a tube, u, containing at the 
 mouth of the cone two or three plates of perforated zinc, for admission of the atmo- 
 sphere. An upright steam-tight tube of zinc, at about the middle of the lowest 
 chamber, < 5 , and is continued to the top of the uppermost chamber, fi, having two lateral 
 branches. This tuba is closed at its lower end, but open at top, and at the ends of the 
 two branches, to give a draught of cool air into the tube, and a rapid flow of heated 
 air from the top of the tube. W, W are pipes which pass externally from about the 
 middle of the chamber t% to near the bottom of the chamber t 3 . At their tops they 
 are of large dimensions, as represented, but diminish gradually to small pipes at 
 bottom. Of these pipes, there should be as many as can be conveniently applied, in 
 order that the process of condensation may be effectually promoted. 
 
 From the second rectifier, R', the steam is conveyed by a pipe, w, of gradually in- 
 creasing dimensions, to near the top of the middle chamber, t, whence it diffuses itself 
 through the three chambers, where it gets condensed. The hottest steam passes into 
 1 1, and is there most powerfully condensed. The main body of the water produced 
 therefrom, either drops directly into the bottom of the chamber £3, or runs down the 
 inclined sides of the chambers if 1 , t% t 3 , thence through the outer pipes W, W, and out 
 at the bottom of the tube, getting partially aerated in its progress, by means of the air 
 ascending constantly through the tube u. 
 
 Z, Z, is an auxiliar steam-pipe from the rectifier R passing twice or thrice close 
 round the water supplying the cistern, A, and terminating in a cylinder which commu- 
 nicates by pipes with the chambers, £ 2 and t 3 ; whereby all the water thus condensed 
 may fall through the perforated zinc plates, into the general discharge tube, u. X is 
 an outer casing of wood or metal, leaving a small space round the condenser, with 
 draught-holes, x, x, for the admission of air. The refrigerator is made of protected 
 metal "(tinned copper?)" and divided into three compartments, y l, y% y 3 . 
 
 In the top of y \ the end of the discharged tube u is inserted ; and at a little distance 
 from this tube there are air apertures, a, a, furnished with shutters in the inside, 
 slanting from the top downwards, to prevent as much as possible the escape outwards 
 of any vapour which may occasionally be carried down with the water from the con- 
 denser. The middle compartment, y 2 , is perforated, convex at top, and concave at 
 bottom; so that the water that drops from the tube u, in the convex top of y% falls off 
 laterally through small pipes into the chamber y 2, while its concave bottom turns the 
 water into a central filtering-box, c, that projects a little into y 3 , set to receive it. 
 For aerating this water, the bottom of y 2 is covered about an inch deep with small 
 pebbles, y 3 , which is the reservoir of the purified cool water, is perforated with small 
 holes, c ', c ', are small pipes for promoting a continual upwards flow of cold air. 
 y 3 is furnished with a tap to draw off its water, as required. 
 
 For re-distilling or rectifying spirituous liquids, the apparatus, fig. 47. is employed ; 
 in which the supply cistern A is much larger, and close at top ; the upper condensing 
 chambers, t l , t% are also larger, but the lowest, * 3 , is narrowed. The second rectifier 
 of fig. 46. is removed. The feints collect in the bottom of the rectifier R, to be drawn 
 off by a cock ; while the rectified spirit passes off at top into the condenser. The refri- 
 gerator has only two compartments, and no pebbles. F is a funnel into which the 
 spirits may be returned for re- distillation. 
 
 For extracting the soluble matter of vegetable infusions, the apparatus, shown in 
 fig. 48., is used. The rectifier is vertical, has a screw-capped hand-hole, /, for admitting 
 the vegetables, g is a steam pipe ; and h is a funnel for returning portions of the 
 liquid extract. R is connected by a pipe, k, with the condenser, T, made in two por- 
 
FATS. 
 
 79 
 
 tions, fitted water-tight together, but separable for the purpose of cleansing. The 
 steam which passes from the boiler into the rectifier R disengages the soluble portion 
 of the vegetable substances, and, if they be volatile, carries them off to the condenser ; 
 if not, it combines and falls with them to the bottom of the vessel, whence this portion 
 of the extract is drawn off by the cock, and a fresh charge may be introduced. The 
 steam is shut off from the rectifier R by a cock on the pipe g. When the steam is 
 afterwards admitted to assist the process of maceration, the supply of it is regulated by 
 the stop-cocks in the pipes g and k. — Newton's Journal, xxiii. p. 247. C. S. 
 
 EXTRACTS. These preparations of vegetables for medicinal use are made 
 either by evaporating the infusions of the dried plant in water, or in alcohol, or the 
 expressed juice of the fresh plant ; and this evaporation may be effected by a naked fire, 
 a sand hath, an air bath, a steam heat, or a liquid balneum of any nature, all of which 
 may be carried on either in the open air, or in vacuo. Of late years, since the vacuum- 
 pan has been so successfully employed in concentrating syrups in sugar-houses, the 
 same system has been adopted for making pharmaceutical extracts. An elegant 
 apparatus of this kind, invented by Mr. Barry, of Plough Court, was made the subject 
 of a patent about 25 years ago. The use of the air-pump for evaporating such chemical 
 substances as are readily injured by heat, has been very common since Professor Leslie's 
 discovery of the efficacy of the combined influence of rarified air, and an absorbing 
 surface of sulphuric acid, in evaporating water at low temperatures. It has been sup- 
 posed that the virtues of narcotic plants in particular might be better obtained and 
 preserved, by evaporation in vacuo than otherwise, as the decomposing agency of heat 
 and atmospheric oxygen would be thereby excluded. There is no doubt that extracts 
 » thus made from the expressed juices of fresh vegetables, possess, for some time at least, 
 the green aspect and odour of the plants in far greater perfection than those usually 
 made in the air, with the aid of artificial heat. Dr. Meurer, in the Archiv. der Phar- 
 macie for April 1843, has endeavoured to show that the colour and odour are of no 
 value in determining the value of extracts of narcotics, that the albumen left unchanged 
 in the extracts made in vacuo, tends to cause their spontaneous decomposition, and that 
 the extracts made with the aid of alcohol, as is the practice in Germany, are more 
 efficacious at first, and much less apt to be injured by keeping. M. Baldenius has, in 
 the same number of the Archiv, detailed experiments to prove that the juices of recent 
 plants mixed with alcohol, in the homoeopathic fashion, are very liable to spontaneous 
 decomposition. To the above expressed juice, the Germans add the alcoholic tincture 
 of the residuary vegetable matter, and evaporating both together, with filtration, pre- 
 pare very powerful extracts. 
 
 F. 
 
 FATS. The following statement is given on the authority of Braconnot : 
 
 
 Oleine. 
 
 Stearine. 
 
 Fresh butter in summer 
 
 60 
 
 40 
 
 in winter 
 
 37 
 
 63 
 
 Hog's Lard - - - - 
 
 62 
 
 38 
 
 Ox Marrow - 
 
 24 
 
 76 
 
 Goose Fat - 
 
 68 
 
 32 
 
 Duck Fat .... 
 
 72 
 
 28 
 
 Ox Tallow - 
 
 25 
 
 75 
 
 Mutton Suet - 
 
 26 
 
 74 
 
 M. Dumas says that butter contains no stearine. The purification and decoloration 
 of fats has been the object of many patents. Under Candle, Hempel's process for 
 refining palm-oil and extracting its margarine is described. 
 
 About 30 years ago, palm-oil was deprived of colour to a certain degree by mixing 
 with the melted oil, previously freed from its impurities by filtration, some dilute nitric 
 acid, wooden vessels being used, and the oil being in a melted state. This process was 
 both expensive and imperfect. More lately whitening has been prescribed by means 
 tf chromic acid, which, in the act of decomposition into chromic oxide, gives out 
 oxygen, and thereby destroys vegetable colours. One pound of bichromate of potash 
 in solution is to be mixed with two pounds of strong sulphuric acid, diluted before- 
 hand with about two gallons of water; and this mixture is to be incorporated by 
 diligent stirring with 2 cwt. of the filtered palm-oil, at a temperature of about 
 100° F, contained in a wooden vessel. The palm-oil is afterwards to be washed in 
 
80 
 
 FERMENTATION. 
 
 warm lime-water, to which some solution of chloride of lime may be advantageously 
 added. By this process, well managed, a fat may be obtained from palm oil fit for 
 making white soap. Tallow may be also blanched to a considerable degree by a like 
 operation. 
 
 Instead of sulphuric acid, the muriatic may be used to convert the chromic acid into 
 chromic oxide in the above process, and thereby to liberate the blanching oxygen. 
 The resulting solution of green muriate of chrome being freed from some adhering oil, 
 is to be mixed with so much milk of lime as just to neutralise the excess of acid that 
 may be present. The clear green muriate is then to be decomposed in a separate 
 vessel, by the addition of well-slaked and sifted lime, in some excess. The green mix- 
 ture of lime and chrome-oxide is now to be dried, and gently ignited, whereby it is 
 converted into yellow chromate of lime, with some unsaturated lime. This compound 
 being decomposed by dilute sulphuric acid, affords chromic acid, to be applied again 
 in the decolouring of palm-oil, on the principles above explained. 
 
 Mr. Prynne obtained a patent in March, 1840, for purifying tallow for the candle- 
 maker, by heating it along with a solution of carbonate of potash or soda for 8 hours, 
 letting the whole cool, removing the tallow to another vessel, heating it by means of 
 steam up to 206° F., along with dry carbonate of potash (pearlash) : letting this mix- 
 ture cool very slowly ; and finally removing the tallow to a vessel inclosed in steam, so 
 as to expel any subsidiary moisture. — Newton's Journal, xxi. 258. 
 
 A patent for a like purpose was obtained in June, 1842, by Mr. H. H.Watson. He 
 avails himself of the blanching power of oxygen, as evolved from manganate of potash 
 (chameleon mineral), in the act of its decomposition by acids, while in contact with 
 the melted fat. He prescribes a leaden vessel {a well-joined wooden tub will also 
 serve) for operating upon the melted tallow, with one twentieth of its weight of the 
 manganate, dissolved in water, and acidulated to the taste. The whole are to be well 
 mixed, and gradually heated from 150° up to 212° F., and maintained at that tem- 
 perature for an hour. On account of the tendency of the dissolved manganate to 
 spontaneous decomposition, it should be added to the dilute acid, mixed with the fat 
 previously melted at the lowest temperature consistent with its fluidity. 
 
 Palm-oil may be well blanched in the course of 1 2 hours by heat alone ; if it be 
 exposed in a layer of one or two inches to the air and sunshine, upon the surface of 
 water kept up at nearly the boiling point by a coil of steam-pipes laid in the bottom of 
 a square cistern of lead or wood, well jointed. 
 
 Tallow imported for home consumption in 1839, 1,148,192 cwt.; in 1840, 1,131.513. 
 Duty, 3.?. 2c?. per cwt. 
 
 FELTED CLOTH. This woollen fabric, made without spinning and weaving, 
 was made the subject of a patent by Mr. T. R. Williams in February, 1840. A copious 
 description of the process is given in Neicton's Journal, xxii. 1. 
 
 Varnished or Japanned Felt is made by imbuing the stuff of coarse hat-bodies with 
 drying oil, prepared by boiling 50 lhs. of linseed oil with white lead, litharge, and 
 umber, of each one pound. The felt is to be dried in a stove, and then polished by 
 pumice-stone. Five or six coats of oil are required. The surface is at last varnished. 
 When the object is intended to be stiff, like visors, the fabric is to be impregnated first 
 of all with flour-paste, then stove-dried, cut into the desired shape, next imbued with 
 the drying-oil, and pumiced repeatedly ; lastly placed, to the number of 20, in a hot 
 iron mould, and exposed to strong pressure. Japanned hats, made in this way, are sold 
 in France at Is. 3d. a piece ; and they will stand several years' wear. 
 
 FERMENTATION. This term has been of late extended to several chemical 
 operations, besides those formerly included under it. The phenomena which it exhibits 
 under these different phases, and the changes which it effects among the various 
 subjects of its operation, are no less striking and mysterious in their principle than 
 important in their applications to the arts of life. Fermentations are now arranged 
 into twelve classes — 1. the alcoholic ; 2. the glucosic or saccharine ; 3. the viscous or 
 mucous ; 4. the lactic ; 5. the acetic ; 6. the gallic ; 7. the pectic ; 8. the benzoilic ; 
 9. the sinapic; 10. the ammoniacal ; 11, the putrid; and 12. the fatty. 
 
 Fermentation, in the most general sense, may be defined to be a spontaneous re- 
 action, a chemical metamorphosis, excited in a mass of organic matter, by the mere 
 presence of another substance, which neither abstracts from nor gives to the matter 
 which it decomposes any thing whatever. This process requires the following con- 
 ditions : — 1. A temperature from 45° to 90° F. ; 2. Water ; 3. The contact of air ; 
 4. The presence of a neutral organic azotised matter, in very small quantity, and of a 
 crystallisable non-azotised substance, in considerable quantity. The former is" the 
 ferment, the latter undergoes fermentation. In ordinary chemical actions we perceive 
 one body unite to another to form a new compound ; or one body turn another out of 
 a combination, and take its place, in virtue of a superior affinity. These effects are 
 foreseen and explained by the intervention of that molecular force which governs -all 
 
i 
 
 FERMENTATION. 81 
 
 chemical operations, that attractive power which unites the particles of dissimilar 
 bodies. Thus, also, in the ordinary phenomena of decomposition, we perceive the 
 agency of heat at one time, at another of light, or of electricity ; forces of which, 
 though we are not acquainted with the essence, yet we know the exact effect under 
 determinate circumstances. But fermentation, on the contrary, can be explained 
 neither by the known laws of chemical affinity nor by the intervention of the powers 
 of light, electricity, or heat. Fermentation reduces complex organic substances to 
 simpler compounds, thereby reducing them nearer to the constitution of mineral 
 nature. It is an operation analogous, in some respects, to that effected by animals upon 
 their vegetable food. 
 
 With a good microscope, any person may convince himself that ferment or yeast is 
 an organised matter, formed entirely of globules, or of corpuscles slightly ovoid, from 
 the three to the four-thousandth part of an inch in diameter. Sometimes their surface 
 seems to have a little tail, which has been regarded as a bud or germ attached to the 
 mother cell. Whenever the fermentation begins, the yeast does not remain an instant 
 idle. These small round bodies become agitated in all directions, and if the substance 
 undergoing fermentation is mixed with an azotized matter, as in beer worts, the cor- 
 puscles become larger, the small tails get developed, and on acquiring a certain size 
 they separate from the parent globule, to live by themselves, and give birth to new 
 corpuscles. * In the fermentation of beer from malt, this series of multiplications 
 produces a quantity of yeast seven times greater than what was added at the commence- 
 ment. Were the above ingenious speculations demonstrated with certainty, we should 
 be led to admit, in all these phenomena, actions truly vital, and a reproduction like 
 that of buds in the vegetable kingdom. The existence of a vital force seems to be 
 rendered probable by the fact, that in incomplete fermentation, such as that of fine 
 syrup with too little yeast, the ferment loses its properties and powers. If, however, we 
 add to the solution of pure sugar an albuminous substance, a caseous or fleshy matter, 
 the development of yeast becomes manifest, and an additional quantity of it is found 
 at the end of the operation. Thus with nourishment, ferment engenders ferment. It 
 is for this reason that a little fermenting must, added to a body of fresh grape-juice, excites 
 fermentation in the whole mass. These effects are not confined to alcoholic ferment- 
 ation. The smallest portions of sour milk, of sour dough, or sour juice of beet-root, 
 of putrefied flesh or blood, occasion like alterations in fresh milk, dough, juice of beet- 
 roots, flesh, and blood. But further, and which is a very curious circumstance, if we 
 put into a liquid containing any fermenting substance, another in a sound state, the 
 latter would suffer decomposition under the influence of the former. If we place urea 
 in presence of beer-ycast, it experiences no change ; while, if we add it to sugar-water 
 in a fermenting state, the urea is converted into carbonate of ammonia. We thus 
 possess two modes of decomposition, the one direct, the other indirect. 
 
 Although yeast has all the appearances of an organised substance, it is merely by ana- 
 logy that its multiplication by growth is assumed, for this is a phenomenon very difficult 
 of experimental demonstration. When blood, cerebral substance, gall, pus, and such like 
 substances, in a putrid state, are laid upon fresh wounds in animals, vomiting, debility, 
 and death soon supervene. The scratches from bones in putrid bodies have been often 
 the causes of disease and death to anatomists. The poison in bad sausages is of the 
 same class of ferments. In Wurtemberg, where sausages are prepared from very 
 miscellaneous matters, as blood, livers, brains, and offal of many other kinds, with 
 bread, meal, salt, and spices, fatal results from eating them are not uncommon. Death 
 in these cases is preceded by the gradual wasting of the muscular fibre, and of all the 
 like constituents of the human body ; so that the patient becomes emaciated, dries into 
 a complete mummy, and soon expires. The cadaver is stiff as if frozen, and is not 
 subject to putrefaction. During the progress of the sausage disease, the saliva becomes 
 viscid, and emits an offensive smell. No peculiar poison can be detected by analysis 
 in the sausages ; but they are rendered wholesome food for animals by the action of 
 alcohol, or by that of boiling water, which destroy the noxious fomes without acquiring 
 it themselves ; and thus decompose the putrefactive ferment of the sausages. When 
 this, however, passes unchanged through the stomach into the circulating system, it 
 imparts its peculiar action to the constituents of the blood, operating upon it as yeast 
 does upon wort. Poisone of a like kind are produced by the body itself in some 
 diseases. In plague, small-pox, measles, &c, substances of a peculiar fermentative 
 nature are generated from the blood, which are capable of inducing in the blood of a 
 healthy person a decomposition like that of which themselves are the subjects. The 
 morbid virus reproduces itself, and multiplies indefinitely, just as the particles of yeast 
 do in the fermentation of beer. The temperature of boiling water, and alcohol applied 
 to matters imbued with such poisonous secretions, render their poison inert. Many 
 
 * M. Turpin, M. Cagniard Latour, M. Quevenne, and Professor Mitscherlich. 
 
 M 
 
82 
 
 FERMENTATION. 
 
 acids, chlorine, iodine, bromine, empyreumatic oils, smoke, creosote, strong decoction 
 of coffee, have the same salutary effect. All these agents are known to counteract 
 fermentation, putrefaction, and that dry wasting of organic matter called eremacausis, 
 or slow combustion. It is most deserving of remark, that the poisons chemically neutral 
 or alkaline, such as those of small-pox in man, and of typhus ruminantium in cows, lose 
 their baneful power when subjected to the action of the stomach ; whereas that of bad 
 sausages, which is acid, resists the modifying power of the digestive organs. 
 
 Alcoholic fermentation lias been copiously discussed in the Dictionary. I may here 
 add that ammonia, being a product of that change in solution of pure sugar, proves the 
 presence of azote in the yeast ; and that sulphuretted hydrogen, being made manifest 
 in the disengaged gaseous products, by their blackening paper imbued with acetate of 
 lead, proves the presence of sulphur. The acid liquor accompanying yeast may be 
 washed away, without impairing materially its fermenting power, while the acid so 
 removed has of itself no such virtue. 
 
 . Yeast, freed from all soluble matters by water, alcohol, and ether, contains, inde- 
 pendently of ashes ; carbon, 50 "6 ; hydrogen, 7\3; azote, 15; oxygen, sulphur, and 
 phosphorus, 27 "1, in 100 parts. Viewed atomically, yeast bears a close analogy to 
 albumen. Like albuminous matter, yeast takes a violet tint with muriatic acid, and it 
 may be replaced as ferment by gluten. Caseum (the curd of milk) and flesh operate 
 the same effect. All these fermentative powers have the same globular appearance in 
 the microscope with yeast. When the activity of yeast has been destroyed by heat, 
 &c. it can be restored by the positive energy of the voltaic battery, which causes its 
 combination with oxygen. The best proportion of sugar and water, for exhibiting the 
 phenomena of fermentation, is 1 of the former to 3 or 4 of the latter, and 5 parts of 
 sugar to 1 of fresh yeast may be added; though in the course of fermentation, 100 parts 
 of sugar do not consume 2 parts of yeast, estimated in the dry state. The quickest fer- 
 menting temperature is from 68° to 86°. A very little oil of turpentine or creosote, 
 or of the mineral acids, prevents or stops fermentation completely ; oxalic and prussic 
 acids have the same effect, as also corrosive sublimate and verdigris. It has been 
 known from time immemorial in Burgundy, that a little red precipitate of mercury, 
 when added to the must-tun, stopped the fermentation. All alkalies counteract 
 fermentation, but when they are saturated it re-commences. The first person who 
 described the microscopic globules of yeast with precision was Desmazieres, who 
 arranged them among the mycodermes (fungus-skinned)., under the name of mycoderma 
 cerevisice. They have not the flattened form of the globules of blood, but are rather 
 egg-shaped. One small black point may be seen on their surface, which, after some 
 days, is associated with 3, 4, or 5 others. Their average diameter is from to 
 of an inch. Sometimes more minute globules cluster round one of ordinary size, and 
 whirl about with it, when the liquor in which the globules float is agitated. 
 
 Fresh yeast loses, by drying, 68 parts in the 100, and becomes solid, horny-looking, 
 and semitransparent, breaking readily into gray or reddish fragments. With water, it 
 resumes immediately its pristine appearance. When fresh yeast is triturated with its 
 own weight of white sugar, it forms a liquid possessing the fluidity of oil of almonds, 
 and a yellow colour. The globules continue unchanged, except perhaps becoming some- 
 what smaller. Yeast in the dry state retains its fermentative virtue for a long time. 
 
 Saccharine Fermentation is that by which starch and dextrine are converted into 
 sugar, as shown remarkably in the action of diastase upon these bodies. If we mix 2 
 parts of starch paste with 1 part of dry gluten, and keep the mixture at a temperature 
 of from 122° to 140° F., we obtain a good deal of sugar and dextrine. Some lactic 
 acid is also formed. Flour paste, long kept, spontaneously produces sugar by a like 
 reaction. See Fermentation in the Dictionary. 
 
 Lactic Fermentation. — Almost all azotised organic matters, after being modified by 
 the contact of air, become capable of giving rise to this fermentation. Oxygen does 
 not come into play, except as the means of transforming the animal substances into a 
 ferment. Diastase and caseum are well adapted to exhibit this change. The body 
 that is to furnish the lactic acid may be any one of the neutral vegetable matters, pos- 
 sessing a like composition with lactic acid, such as cane sugar, grape or potato sugar, 
 dextrine, and sugar of milk. All the agents which stop the alcoholic, stop also the 
 lactic fermentation ; while diastase and caseum are its two best exciters. For pro- 
 ducing abundance of lactic acid, we have merely to moisten malt, to expose it to the 
 air for a few days, then to triturate it with a quantity of water, and leave the emulsion 
 for some days more in the air, at a temperature between 67° and 86° F. We then 
 saturate the liquor with chalk, after having filtered it, and thereby obtain the lactate of 
 lime, which may be crystallised in alcohol, to deprive it of the dextrine and earthy 
 phospahtes ; and then decomposed by sulphuric acid. 
 
 Lactic Acid, formed from curd (caseum), exhibits more remarkable phenomena. Thus 
 when milk is left alone for some time it becomes sour, and coagulates. The coagulum 
 
FERMENTATION. 
 
 83 
 
 is formed of caseum and butter; while the whey of it contains sugar of milk and some 
 salts. The coagulation of the caseum has been occasioned by the lactic acid, which 
 was generated in consequence of an action which the caseum itself exercised upon the 
 sugar of milk. Thus with the concourse of air, the caseum becomes a ferment, and 
 excites the conversion of the sugar of milk into lactic acid. The lactic acid in its turn 
 coagulates the caseum, which in the consolidation of its particles attracts the butter 
 The caseum then ceases to act upon the sugar of milk, and consequently produces no 
 more lactic acid. 
 
 But noAv, if the lactic acid already formed be saturated, the caseum will re-dissolve, 
 and the phenomena will re-commence in the same order. This is easily done by adding 
 a due dose of bicarbonate of soda to the soured milk. In the course of 30 hours, a 
 fresh portion of lactic acid will be generated, and will have coagulated the milk again. 
 We may also add some sugar of milk to the liquid, and to a certain extent convert it 
 into lactic acid. Milk boiled, and kept from contact of air, will not coagulate, and 
 remains fresh for many months. Animal membranes, modified by exposure to moist air 
 for some time, form a true ferment for the lactic fermentation, and acidify solutions of 
 sugar, dextrine, and gum, but the membranes must not be putrescent. Cane-sugar, 
 starch-sugar, and sugar of milk, by assuming or losing a little water, acquire the con- 
 stitution of lactic acid. 
 
 Viscous or Mucous Fermentation. — Every one is acquainted with this spontaneous 
 modification of white wine and ale, which gives them a stringy or oily aspect, and is 
 called in French graisse, or fat of wines, and in English the ropiness of beer. The 
 viscous fermentation may be excited by boiling yeast with water, and dissolving sugar 
 in the decoction, after it has been filtered. The syrup should have a specific gravity 
 from 1 *040 to 1 '055, and be kept in a warm place. It soon assumes the consistence 
 and aspect of a thick mucilage, like linseed tea, with the disengagement of a little car- 
 bonic acid and hydrogen, in the proportion of 2 or 3 of the former gas to 1 of the 
 latter. A ferment of globular texture like that of yeast is formed, which is capable 
 of producing viscous fermentation in any saccharine solution to which it is added, pro- 
 vided the temperature be suitable. The viscid matter being evaporated to dryness 
 forms transparent plates, of a sub-nauseous taste, and soluble in water, but less easily 
 than gum arabic. Its mucilage is, however, thicker than that of gum, and yields with 
 nitric acid, oxalic acid, but no mucic acid. Four parts of sugar, treated as above 
 described, furnish 2*84 of unchanged sugar, and 1-27 of the mucilage ; from which it 
 appears that water becomes fixed in the transformation. Muriatic, sulphuric, sulphur- 
 ous acids, and alum, prevent the production of the viscous fermentation, by precipitating 
 its ferment. It is probably the soluble portion of gluten which is the cause of this species 
 of fermentation. It has been found, accordingly, that tannin, which precipitates the said 
 glutinous ferment, completely stops the viscous fermentation, or graisse, of wines. It 
 is owing to the tannin which the red wines derive from the grape stalks, with which 
 they are long in contact during fermentation, that they are preserved from this 
 malady of the white wines. The gluten of must is of two kinds, the one soluble in 
 virtue of the alcohol and tartaric acid, and producing the viscous, the other insoluble, 
 and producing the alcoholic fermentation. The art of the wine maker consists in 
 precipitating the injurious ferment, without impeding the action of the beneficial one ; 
 an art of considerable delicacy with regard to sparkling wines- 
 
 Acid Fermentation has been fully discussed under acetic acid. It requires the pre- 
 sence of ready formed alcohol and air. The lactic fermentation, on the contrary, may 
 take place with starchy or saccharine substances, without the intervention of alcohol or 
 constant exposure to the atmosphere ; and when once begun, it can go on without air. 
 Acetification has a striking analogy with nitrification, as is shown by the necessity of a 
 high temperature, and the utility of porous bodies for exposing the liquid on a great 
 surface to the air. 
 
 Benzoic Fermentation is that which transforms the azotised neutral crystalline matter, 
 existing in bitter almonds, which has no action upon the animal economy, into new and 
 remarkable products, amongst others the hydrure of benzbile and hydrocyanic (prussic) 
 acid, which together constitute the liquid, called oil, or essence, of bitter almonds, a 
 compound possessed of volatility and poisonous qualities. The attentive study of this 
 fermentation has revealed a great fact in vegetable physiology, the spontaneous pro- 
 duction, by means of certain artifices, of certain volatile oils, not pre-existing in the 
 plants, yet capable of being generated in the products of their decomposition. The 
 volatile oil of bitter almonds constitutes in this respect a starting point, from which 
 have proceeded the oil of mustard, the oil of spiraea, and which will likely lead to other 
 discoveries of the same kind. See Almond and Amygdaline. 
 
 Sinapic Fermentation is that by which the oil of mustard is formed, and which takes 
 place by the contact of water, under certain conditions, of too refined and scientific a 
 nature for this practical work. 
 
 M 2 
 
84 
 
 FERMENTATION. 
 
 Pectic Fermentation. — Pectic acid may be obtained from the expressed juice of 
 carrots, and it seems to be formed in the process of extraction by the reaction of albu- 
 mine in the carrots upon a substance called pectine ; a transformation analogous there- 
 fore with that which takes place in the formation of the essence of bitter almonds. 
 
 Gallic Fermentation. — Gallic acid does not exist ready formed in nut-galls, but is 
 generated from their tannin when they are ground, made pasty with water, and exposed 
 to the air. This conversion may be counteracted by the red oxide of mercury, alcohol, 
 sulphuric, muriatic, and nitric acids, bromine, essence of turpentine, creosote, oxalic, 
 acetic, and prussic acids. The tannin disappears in the sequel of the above metamor- 
 phosis. 
 
 Fatty Fermentation. — All fats are transformed by the action of an alkaline or other 
 base into certain acids, the stearic, margaric, the oleic, ethalic, &c. When these acids are 
 once formed, they cannot by any means, hitherto known, be reconverted into the primitive 
 fat. By the fixation of water in the acid and the base (called glycerine), a change is 
 effected which cannot be undone, because the glyceric base is incapable by itself to dis- 
 place the water, once combined in the hydrated fat acid. The circumstances necessary 
 to the fatty fermentation, are like those of other fermentations ; namely, the co-operation 
 of an albuminoid matter, along with water, and a temperature of from 60° to 86° F. ; 
 under these conditions, the matter becomes warm, and assumes speedily the character 
 of rancidity ; acid is generated, and the carbonate of soda can then form salts, while the 
 fatty acid is liberated ; a circumstance impossible when the fat was acted upon in the 
 neutral state. This altered fat, treated with water, gives up to it glyceric alcohol. 
 
 Digestive Fermentation. — Digestion of food may be considered in its essential features 
 as a peculiar fermentative process. The gastric juice is a genuine ferment. Tiedmann, 
 Gmelin, and Prout have shown that the gastric juice contains muriatic acid; and 
 Eberli has made interesting experiments on the digestion of food out of the body, with 
 water containing a few drops of the same acid. He observed that when this liquid con- 
 tained none of the mucous secretion of the stomach, it did not dissolve the aliments put 
 into it ; but with a little of that mucus it acquired that property in an eminent degree. 
 Even the mucus of the bladder had a like effect. Schwann and Vogel have produced 
 this digestive principle in a pure state, called by them pepsine, as obtained most abun- 
 dantly from the stomachs of swine. The glandular part of that viscus being separated 
 from the serous, is cut into small pieces, and washed with cold distilled water. After 
 digestion for 24 hours, that water is poured off, and fresh water is poured on. This 
 operation is repeated for several days, till a putrid odour begins to be felt The watery 
 infusion thus obtained is precipitated by acetate of lead. This white flaky precipitate 
 contains the pepsine, accompanied with much albumen. It is then washed, mixed with 
 water, and subjected to a stream of sulphuretted hydrogen. The whole being now 
 thrown on a filter, the coagulated albumen remains on the paper, along with the sul- 
 phuret of lead, while the pepsine liquor passes, associated with some acetic acid. If to 
 this liquor a very small quantity of muriatic acid be added, it becomes capable of carry- 
 ing on artificial digestion. Dry pepsine may be obtained by evaporating the above 
 filtered liquor on a water bath, to a syrupy consistence, then adding to it absolute 
 alcohol, which causes a bulky whitish precipitate. This dried in the air constitutes 
 pepsine. It contains a minute quantity of acetic acid, which may be removed com- 
 pletely, by heating it some hours on the water bath. The white powder then obtained 
 is soluble in water, and betrays the presence of no acid whatever. According to Vogel, 
 this substance is composed of, carbon, 57*72; hydrogen, 5-61 i azote, 21 "09; oxygen, 
 &c. 15*52 = 100. Vogel has proved the analogy between the action of pepsine and 
 diastase by the following experiment : 
 
 He dissolved two grains of pepsine in very weak muriatic acid, and put into this 
 liquor heated to 81° F., small bits of boiled beef. In the course of a few hours the 
 pieces became transparent on their edges, and not long after they were completely dis- 
 solved. He now added fresh morsels in succession, till those last put in remained un- 
 changed. He found by analysis, that 1 *98 grains of the pepsine were left, showing 
 how minute a portion of this ferment was necessary to establish and effect digestion. 
 In fact, we may infer that pepsine, like yeast, serves to accomplish digestion without 
 any waste of its own substance whatever, or probably with its multiplication. 
 
 Rennet, with which milk is coagulated in making cheese, is somewhat of the same 
 nature as pepsine. It has been called chymosine. But the simplest digesting liquor is 
 the following : 
 
 If 10,000 parts of water by weight be mixed with 6 parts of ordinary muriatic acid 
 and a little rennet, a liquor is obtained capable of dissolving hard boiled white of egg, 
 beef, gluten, &c. into a transparent jelly in a few hours. 
 
 Ammoniacal Fermentation. — Under this title may be described the conversion of urea 
 into carbonate of ammonia under the influence of water, a ferment, and a favourable 
 temperature. Urea is composed in atoms ; reckoned 
 
FERMENTATION. 
 
 80 
 
 In volumes, Carbon 4 ; hydrogen 8 ; azote 4 ; oxygen 2 ; 
 
 which by fixing — 4 ; — 2 ; 
 
 give 4; 12; 4; 4: 
 
 which is 4 vol. of carbonic acid, and 8 of ammonia ; equivalent to ordinary carbonate of 
 ammonia. The fermentation of urea plays an important part in the reciprocal offices 
 of vegetable and animal existence. By its conversion into carbonate of ammonia, urea 
 becomes a food fit for plants ; and by the intervention of the mucous ferment which urine 
 contains, that conversion is effected. Thus the urea constitutes a neutral and innocu- 
 ous substance while it remains in the bladder, but is changed into a volatile, alkaline, 
 and acrid substance when it is acted upon by the air. Yeast added to pure urea mixed 
 with water, exercises no action on it in the course of several days ; but when added to 
 urine, it soon causes decomposition, with the formation of carbonate of ammonia, and 
 disengagement of carbonic acid. The deposit on chamberpots iil-cleaned acts as a very 
 powerful* ferment on urine, causing the complete decomposition of fresh urine in one 
 fifth of the time that would otherwise be requisite. 
 
 Nitrous Fermentation, as exhibited in the formation of nitric acid from the atmosphere, 
 and consequent production of nitrates in certain soils, has been with much probability 
 traced to the action of ammonia on oxygen, as the intermedium or ferment. 
 
 Caseous and putrid Fermentations. — Curd is converted into cheese, when after being 
 coagulated by rennet, it is left to itself under certain conditions ; and this constitutes the 
 true distinctive character of caseum. In the production of cheese there is evidently the 
 intervention of a peculiar ferment which is gradually formed, and the decomposition of 
 the curd into new products. 
 
 For animal and vegetable matters to run into putrefaction, they must be in contact 
 with air and water, at a certain temperature ; viz. between the freezing and boiling 
 points of water. The contact of a putrid substance acts as a ferment to fresh animal 
 and vegetable matters. The reagents which counteract fermentation in general stop 
 also putrefaction. In this process, myriads of microscopic animalcules make their ap- 
 pearance, and contribute to the destruction of the substances. 
 
 A dispute having taken place between some distillers in Ireland and officers of 
 Excise, concerning the formation of alcohol in the vats or tuns by spontaneous fermen- 
 tation, without the presence of yeast, the Commissioners of Excise thought fit to 
 cause a series of experiments to be made upon the subject, and they were placed 
 under my general superintendence. An experiment was made on the 6th of October, 
 with the following mixture of corn : — 
 
 2 Bushels of Barley, weighing - - - - 1 OOlbs. 5 oz. 
 
 1 Bushel of Malt, - - - - - 21 7 
 
 £ Bushel of Oats, - • - - - 20 1 2 
 
 Total, 3 Bushels, weighing - - - 142 8 
 
 The bruised corn was wetted with 26 gallons of water at the temperature of 160° F., 
 and, after proper stirring, had 8 gallons more of water added to it at the average tem- 
 perature of 194°. The mash was again well stirred, and at the end of 45 minutes 
 the whole was covered up, having at that time a temperature of 138° F. Three hours 
 afterwards, 16 gallons of wash only were drawn off ; being considerably less than 
 should have been obtained, had the apparatus been constructed somewhat differently, 
 as shall be presently pointed out. The gravity of that wash was 1 -060, or, in the lan- 
 guage of the distiller, 60°. After a delay of two hours more, twenty additional 
 gallons of water at the temperature of 200° were introduced, when the mash was well 
 stirred, and then covered up for two hours, at which period 23 gallons of fine worts 
 of specific gravity 1-042 were drawn off. An hour afterwards 12 gallons of water at 
 200° were added to the residual grains, and in an hour and a half 1 1 gallons of wort 
 of the density 1 -033 were obtained. Next morning the several worts were collected 
 in a new mash tun. They consisted of 48 gallons at the temperature 80°, and of a 
 specific gravity 2*0465 when reduced to 60°. Being set at 80°, fermentation soon 
 commenced; in two days the specific gravity had fallen to 1*0317, in three days to 
 1*018, in four days to 1*013, and in five days to 1 *012, the temperature having at last 
 fallen to 78° F. The total attenuation was therefore 34i°, indicating the production 
 of 3*31 gallons of proof spirit, while the produce by distillation in low wines was 3*22; 
 and by rectification in spirits and feints it was 3 05. The next experiment was com- 
 menced on the ] 2th of October, upon a similar mixture of corn to the preceding. 
 48 gallons of worts of 1 *043 specific gravity were set at 82° in the tun, which next 
 day was attenuated to 1*0418, in two days to 1*0202, in three days to 1*0125, and in 
 five days to 1*0105, constituting in the whole an attenuation of 321°, which indicates 
 
86 
 
 FERMENTATION. 
 
 the production of 3-12 gallons of proof spirits; while the produce of the first distilla- 
 tion was 2-93 in low wines, and that of the second in feints and spirits was 2*66. In 
 these experiments the wash, when fermenting most actively, seemed to simmer and boil 
 on the surface, with the emission of a hissing noise, and the copious evolution of car- 
 bonic acid gas. They prove beyond all doubt that much alcohol may be generated in 
 grain worts without the addition of yeast, and that, also, at an early period ; but the 
 fermentation is never so active as with yeast, nor cloes it continue so long, or proceed 
 to nearly the same degree of attenuation. I was never satisfied with the construction 
 of the mash tun used in these experiments, and had accordingly suggested another 
 form, by which the mash mixture could be maintained at the proper temperature 
 during the mashing period. It is known to chemists that the diastase of malt is the 
 true saccharifying ferment which converts the fecula, or starch of barley and other 
 corn, into sugar ; but it acts beneficially only between the temperatures of 145° and 
 168° F. When the temperature falls below the former number, saccharification lan- 
 guishes ; and when it rises much above the latter, it is entirely checked. The new 
 mash tun was made of sheet zinc, somewhat wider at bottom than top ; it was 
 placed in a wooden tun, so much larger as to leave an interstitial space between the 
 two of a couple of inches at the sides and bottom. Through this space a current 
 of water at 160° was made to circulate slowly during the mashing period. Three 
 bushels of malt, weighing 125 lbs. 3 oz., were wetted with 30 gallons of water at 167°, 
 and the mixture being well agitated, the mash was left covered up at a temperature 
 of 140° during three hours, when 19 gallons of fine worts were drawn off at the spe- 
 cific gravity of 1*0902 or 90-2 0 ., Twenty gallons more water at 167° were then added 
 to the residuum, which afforded after two hours 28 gallons of wort at the gravity 
 1-036; 12 gallons of water at 167° were now poured on, which yielded after other 
 two hours 15 gallons at the gravity 1-0185. Forty gallons of fine worts at 1*058 
 gravity and 68° temperature were collected in the evening of the same day, and let 
 into the tun with 5 per cent, of yeast. The attenuation amounted in six days to 54°. 
 The third wort of this brewing, amounting to 15 gallons, being very feeble, was mixed 
 with 7 gallons of the first and second worts, put into a copper, and concentrated by 
 boiling to 1 1 gallons, which had a gravity of 1 "058 at 60° F. They were separately 
 fermented with 5 per cent, of yeast, and suffered an attenuation of 48± 0 . The produce 
 of spirit from both indicated by the attenuation was 5*36 gallons ; the produce in low 
 wines was actually 5*52, and that in spirits and feints was 5*33, being a perfect accord- 
 ance with the Excise tables. 
 
 The next experiments were made with a view of determining at what elevation of 
 temperature the activity or efficiency of yeast would be paralysed, and how far the 
 attenuation of worts could be pushed within six hours, which is the time limited by 
 law for worts to be collected into the tun, from the time of beginning to run from the 
 coolers. When worts of the gravity 1-0898 were set at 96° Fahr., with 5 per cent, of 
 yeast, they attenuated 26*9° in 6 hours ; worts of 1-0535 gravity set at 110° with 
 5 per cent, of yeast, attenuated 16° in about 5 hours; but when worts of 1 *0533 were 
 set, as above, at 120 a , they neither fermented then, nor when allowed to cool; show- 
 ing that the activity of the yeast was destroyed. When fresh yeast was now added to 
 the last portion of worts, the attenuation became 5-8° in 2 hours, and 28*4° in 3 days; 
 showing that the saccharine matter of the worts still retained its fermentative faculty. 
 Malt worts, being brewed as above specified, were set in the tun, one portion at a tem- 
 perature of 70°, with a gravity of 1 *0939, and 5 per cent of yeast, which attenuated 
 66° in 3 days ; other two portions of the same gravity were set at 120° with about 10 
 per cent, of yeast, which underwent no fermentative change or attenuation in 6 hours, 
 all the yeast having fallen to the bottom of the tuns. When these two samples of 
 worts were allowed, however, to cool to from 74° to 72°, fermentation commenced, 
 and produced in two days an attenuation of about 79°. It would appear, from these 
 last two experiments, that yeast to the amount of 5 per cent, is so powerfully affected 
 by strong worts heated to 120° as to have its fermentative energy destroyed; but that 
 when yeast is added to the amount of 10 per cent., the 5 parts of excess are not per- 
 manently decomposed, but have their activity merely suspended till the saccharine 
 liquid falls to a temperature compatible with fermentation. Yeast, according to my 
 observations, when viewed in a good acromatic microscope, consists altogether of trans- 
 lucent spherical and spheroidal particles, each of about the 6000th part of an inch in 
 diameter. When the beer in which they float is washed away with a little water, they 
 are seen to be colourless ; their yellowish tint, when they are examined directly from 
 the fermenting square or round of a porter brewery, being due to the infusion of the 
 brown malt. The yeast of a square newly set seems to consist of particles smaller 
 than those of older yeast, but the difference of size is not considerable. The re- 
 searches of Schulze, Cagniard de la Tour, and Schwann, appear to show, that the 
 vinous fermentation, and the putrefaction of animal matters — processes which have been 
 
FERMENTATION. 
 
 87 
 
 hitherto considered as belonging entirely to the domain of chemical affinity — are 
 essentially the results of an organic development of living beings. This position 
 seems to be established by the following experiments : — 1. A matrass or flask con- 
 taining a few bits of flesh, being filled up to one-third of its capacity with water, was 
 closed with a cork, into which two slender glass tubes were cemented air-tight. Both 
 of these tubes were passed externally through a metallic bath, kept constantly melted, 
 at a temperature approaching to that of boiling mercury. The end of one of the 
 tubes, on emerging from the bath, was placed in communication with a gasometer. 
 The contents of the matrass were now made to boil briskly, so that the air contained 
 in it and the glass tubes was expelled. The matrass being then allowed to cool, a 
 current of atmospherical air was made constantly to pass through it from the gasome- 
 ter, while the metallic bath was kept constantly hot enough to decompose the living 
 particles in the air. In these experiments, which were many times repeated, no infu- 
 soria or fungi appeared, no putrefaction took place, the flesh underwent no change, 
 and the liquor remained as clear as it was immediately after being boiled. As it was 
 found very troublesome to maintain the metallic bath at the melting pitch, the follow- 
 ing modification of the apparatus was adopted in the subsequent researches. A flask 
 of three ounces capacity, being one-fourth filled with water and flesh, was closed with 
 a tight cork, secured in its place by wire. Two glass tubes were passed through the 
 cork ; the one of them was bent down, and dipped at its end into a small capsule con- 
 taining quicksilver, covered with a layer of oil ; the other was bent on leaving the 
 cork, first into a horizontal direction, and downwards for an inch and a half, afterwards 
 into a pair of spiral turns, then upwards, lastly horizontal, whence it was drawn out to a 
 point. The pores of the cork having been filled with caoutchouc varnish, the contents 
 of the flask were boiled till steam issued copiously through both of the glass tubes, and 
 the quicksilver and oil became as hot as boiling water. In order that no living par- 
 ticles could be generated in the water condensed beneath the oil, a few fragments of 
 corrosive sublimate were laid upon the quicksilver. During the boiling, the flame of 
 a spirit lamp was drawn up over the spiral part of the second glass tube, by means of 
 a glass chimney placed over it, so as to soften the glass, while the further part of the 
 tube was heated by another spirit lamp, to prevent its getting cracked by the condens- 
 ation of the steam. After the ebullition had been kept up a quarter of an hour, the 
 flask was allowed to cool, and get filled with air through the hot spiral of the second 
 tube. When the contents were quite cold, the end of this tube was hermetically 
 sealed, the part of it between the point and the spiral was heated strongly with the 
 names, and the lamps were then withdrawn. The matrass contained now nothing but 
 boiled flesh and gently ignited air. The air was renewed occasionally through the 
 second tube, its spiral part being first strongly heated, its point then broken off, and 
 connected with a gasometer, which caused the air to pass onwards slowly, and escape 
 at the end of the first tube immersed in the quicksilver. The end of the second tube 
 was again hermetically closed, while the part interjacent between it and the spiral was 
 exposed to the spirit flame. By means of these precautions, decoctions of flesh were 
 preserved, during a period of six weeks, in a temperature of from 14° to 20° R. (63 A° 
 to 77° F. ), without any appearance of putrefaction, infusoria, or mouldiness : on open- 
 ing the vessel, however, the contents fermented in a few days, as if they had been 
 boiled in the ordinary manner. In conducting such researches, the greatest pains 
 must be taken to render the cork and junctions of the glass tubes perfectly air-tight. 
 The following more convenient modification of the experiment, but one equally suc- 
 cessful and demonstrative, was arranged by F. Schulze. The glass tubes connected 
 with the flask were furnished each with a bulb at a little distance from the cork ; into 
 one of which globes caustic alkaline lye being put, and into the other strong sul- 
 phuric acid, air was slowly sucked through the extremity of the one tube, while it 
 entered at the other, so as to renew the atmosphere over the decoction of flesh in the 
 flask. In another set of experiments, four flasks being filled with a solution of cane- 
 sugar containing some beer-yeast, were corked and plunged in boiling water till they 
 acquired its temperature. They were then taken out, inverted in a mercurial bath, 
 uncorked, and allowed to cool in that position. From one-third to one-fourth of their 
 volume of atmospherical air was now introduced into each of the flasks ; into two of 
 them through slender glass tubes kept red hot at a certain point, into the other two 
 through glass tubes not heated. By analysis it was found that the air thus heated 
 contained only 19 '4 per cent, of oxygen, instead of 20-8 ; but, to compensate for this 
 deficiency, a little more air was admitted into the two flasks connected with the heated 
 tubes than into the two others. The flasks were now corked and placed in an in- 
 verted position, in a temperature of from 10° to 14° R. (54i° to 63 £° F.). After a 
 period of from four to six weeks, it was found that fermentation had taken place in 
 both of the flasks which contained the non-ignited air — for, in loosening the corks, 
 some of the contents were projected with force — but, in the other two flasks, there 
 
88 FERRIC-CYANIDE OF POTASSIUM. 
 
 was no appearance of fermentation, either then, or in double the time. As the extract 
 of nux vomica is known to be a poison to infusoria (animalcules), but not to vegetating 
 mould, while arsenic is a poison to both, by these tests it was proved that the living 
 particles instrumental to fermentation belonged to the order of plants of the Confer- 
 void family. Beer yeast, according to Schwann, consists entirely of microscopic fungi, 
 in the shape of small oval grains of a yellowish white colour, arranged in rows oblique 
 to each other. Fresh grape must contains none of them ; but after being exposed to 
 the air at 20° R., for 36 hours, similar grains become visible in the microscope, and 
 may be observed to grow larger in the course of an hour, or even in half that time. 
 A few hours after these plants are first perceived, gas begins to be disengaged. They 
 multiply greatly in the course of fermentation, and at its conclusion subside to the 
 bottom of the beer in the shape of a yellow white powder. 
 
 FERRIC ACID. This new compound having been prescribed as a source of sup- 
 plying oxygen to persons confined in diving-bells and in mines, by M. Payerne, in a 
 patent recently granted to him, merits notice in a practical work. M. Fremv is 
 the discoverer of this new acid, which he obtains in the state of ferrate of pot- 
 ash, by projecting 10 parts of dry nitre in powder upon 5 parts of iron filings, 
 ignited in a crucible ; when a reddish mass, containing much ferrate of potash, is 
 formed. The preparation succeeds best when a large crucible, capable of holding 
 about a pint of water, is heated so strongly that the bottom and a couple of inches 
 above it, appear faintly, but distinctly red, in which state the heat is just adequate to 
 effect due deflagration without decomposition. An intimate mixture of about 200 grains 
 of dried nitre with about one half its weight of the finest iron filings, is to be thrown at 
 once upon the side of the crucible. The mixture will soon swell and deflagrate. The 
 crucible being taken from the fire, and the ignited mass being cooled, is to be taken 
 out with an iron spoon, pounded, immediately put into a bottle, and secluded from the 
 air, in which it would speedily attract moisture, and be decomposed. It is resolved 
 by the action of water, especially with heat, into oxygen gas, peroxide, and nitrate 
 of iron. 
 
 Mr. J. D. Smith prepares the ferrate of potash by exposing to a full red heat a mix- 
 ture of finely powdered peroxide of iron with four times its weight of dry nitre. It 
 has an amethyst hue, but so deep as to appear black, except at the edges. Oxygen is 
 rapidly evolved by the action of the sulphuric or nitric acid upon its solution. He 
 considers the atom of iron to exist in this compound, associated with 3 atoms of 
 oxygen, or double the proportion of that in the red oxide. Hence 52 grains of pure ferric 
 acid should give off 12 grains of oxygen, equal to about 35 cubic inches; but how 
 much of the ferrate of potash may be requisite to produce a like quantity of oxygen, 
 cannot be stated, from the uncertainty of the operation by which it is produced. 
 
 FERRIC-CYANIDE OF POTASSIUM, or Red Prussiate of Potash. This 
 beautiful and useful salt, discovered by L. Gmelin, is prepared by passing chlorine gas 
 through a weak solution of the prussiate of potash (ferro-cyanide of potassium) till it 
 ceases to affect solution of red sulphate of iron, taking care to agitate the liquid all the 
 while, and not to add an excess of chlorine. On looking through the weak solution 
 to the flame of a candle, one may see the period of change from the greenish to the 
 red hue, which indicates the completion of the process. The liquor being filtered and 
 evaporated in a dish with upright sides, will eventually afford crystalline needles, pos- 
 sessed of an almost metallic lustre, and a yellow colour, inclining to red. These being 
 dissolved and re-crystallised, will become extremely beautiful. This salt is composed 
 of 33*68 parts of potassium, 16-48 of iron, and 47*84 of cyanogen. It is therefore a 
 dry salt. It dissolves in 38 parts of cold water, and as it forms then the most delicate 
 test of the protoxide of iron, is very useful in Chlorometry. — See Appendix. 
 
 The solution of this salt affords the following coloured precipitates with the solu- 
 tions of the respective metals : — 
 
 Titanium - Brownish yellow. 
 
 Uranium - Reddish brown. 
 
 Manganese - Brownish grey. 
 
 Cobalt - Deep reddish brown. 
 
 Nickel - Yellowish brown. 
 
 Copper - Dirty yellowish brown. 
 
 Silver - - - Orange yellow. 
 
 Mercury - - - Yellow, with both the protoxide and 
 
 peroxide salts. 
 
 Tin - - - White. 
 
 Zinc - Orange Yellow. 
 
 Bismuth - - - Yellowish brown. 
 
 Lead - - - No precip. 
 
 Iron protoxide - - Blue. 
 peroxide - - No precip. 
 
FLAX AND TOW. 
 
 89 
 
 The ferric-cyanide of potassium has been introduced into dyeing and calico-printing. 
 
 In case an excess of chlorine has been used in preparing the above salt, Posselt 
 recommends to add to its solution, when near the crystallising point, a few drops of 
 potash ley, in order to decompose a green substance that is present, which takes place 
 with the precipitation of a little peroxide of iron. 
 
 FIRE-ARMS. Barrel-welding by Machinery. — The barrels of musquets, birding- 
 guns, &c, or what are called plain, to distinguish them from those denominated stub or 
 twisted barrels, have of late years been formed by means of rolls, a process in which 
 the welding is first effected on a short slab of thick iron, and then the barrel is brought 
 down to its destined length, and form, by repeatedly passing it between a pair of rolls, 
 that have been previously grooved to the exact shape of the barrel intended to be made. 
 
 This method has entirely superseded the skelp-welding by hand described in the 
 Die. of Man. p. 471., and is conducted as follows : — 
 
 The iron being thoroughly refined, and reduced into flat bars by the process de- 
 scribed at length at p. 705., is cut by the shears into slabs or lengths of 10 to 1 '2 inches, 
 and 10 to 10^ lbs. weight, or less, according to the description of gun-barrel that is 
 intended to be made. These slabs are then heated, and bent in their whole length, by 
 means of conveniently grooved bending rolls, until they assume the form of rough tubes, 
 
 ^ of the kind of section shewn by A., fig. 49. They are then placed on the 
 
 O hearth of the reverberatory furnace {Diet. p. 701.), and brought to a full 
 welding heat, and as soon as the edges of a tube come to a semi-fluid state, 
 it is taken out and passed between rolls having grooves somewhat smaller 
 in diameter than the exterior of the tube, by which means the tube 
 is perfectly welded from end to end ; and if care be taken in the 
 management of the heat, and the juncture be kept clear of dirt and cinders, the iron 
 will be found perfectly homogeneous in every part, and there will be no appearance 
 whatever of the seam where the edges came together. These tubes are repeatedly 
 heated, and passed between the barrel rolls, which are of sufficient diameter to admit 
 of gradually decreasing grooves, the whole length of the intended barrel being indented 
 on their surfaces. 
 
 To preserve the tubular form, and ensure regularity in the size of the bore during 
 the welding process, they are taken out of the furnace, by thrusting into them a tool 
 called a mandril b., which consists of a long rod of iron, having a short steel treblett on 
 its end, of the diameter that the bore of the barrel is meant to be. ' This rod is so 
 adjusted by means of a strong iron plate c. near its handle, which is of wood, and long, 
 that when passed with the heated tube on it between two transverse holding bars, the 
 short steel treblett d. shall be found exactly between the point of impact of the barrel- 
 rolls, E E. 
 
 50 
 
 G 
 
 The adhesion of the hot iron to the surface of the rolls is strong enough to draw 
 the tube off the mandril, which thus keeps the bore open from end to end, and by 
 repeating the process through the whole series of grooves in the rolls, the barrel is 
 gradually elongated, and brought down to the exact form required : any superfluous 
 length at the muzzle is then cut. off. The breach end is then adjusted by the hammer 
 — a tripple-seat welded on by hand if it be intended for a percussion lock, and then 
 the barrel is ready to go forward to the mill to be bored, turned, and finished. 
 
 Gun barrels formed by this mechanical method are found to stand proof better than 
 those worked by hand, because the heat is more equalised ; and any imperfections in 
 the original mass of iron are more dispersed over the whole extent of the tube. 
 
 Mr. Wells Ingram, of Bradford Street, Birmingham, has lately perfected a very com- 
 plete lathe for turning the exterior of gun ban-els of all descriptions, a process which is 
 fast superseding the use of the grindstone, for equalising the barrels of all kinds of fire- 
 arms. 
 
 / am indebted for this article to Mr. Lovett, Director of the Royal Arms Manufactory. 
 See Musquet. 
 
 FLAX and TOW, or Codilla of Hemp and Flax, imported for home consumption 
 in 1839, 1,216,811 cwt. ; in 1840, 1,256,322; Id. per cwt. 
 
 N 
 
90 
 
 FUEL. 
 
 FLOOKAN. The name given by the Cornish miners to a vein of clay-stone, often 
 nearly vertical. 
 
 FLOOR CLOTH MANUFACTURE has become of late years a very large 
 branch of trade. The cloth is a strong somewhat open canvas, woven of flax with a 
 little hemp, and from 6 to 8 yards wide, being manufactured in appropriate looms 
 chiefly at Dundee. A piece of this canvas from 60 to 100 feet in length, is secured 
 tight in an upright open frame of oaken bars, in which position it receives the founda- 
 tion coats of paint, 2 or 3 in number, first on the back side, and then on the front ; but 
 it previously is brushed over with glue-size, and rubbed smooth with pumice stones. 
 The foundation paint made with linseed oil and ochre, or any cheap colouring matter, 
 is too thick to be applied by the brush, and is therefore spread evenly by a long narrow 
 trowel, held in the right hand, from a patch of it laid on just before with a brush in the 
 left hand of the workman. Each foundation coat of the front surface is smoothed by 
 pumice whenever it is hard enough to bear the operation. When both sides are dry, the 
 painted cloth is detached from the frame, coiled round a roller, in this state transferred 
 to the proper printing room, where it is spread flat on a table, and variously figured 
 and coloured devices are given to it by wooden blocks, exactly as in the block printing 
 of calicoes, and in the wood-printing of books. The blocks of the floor cloth manufac- 
 ture are formed of two layers of white deal and one of pear-tree timber, placed with 
 their grain crossing one another alternately. There is of course a block for each colour 
 in the pattern, and in each block those parts are cut away that correspond to the im- 
 pressions given by the others ; a practice now well understood in the printing of two or 
 more colours by the press. The faces of the blocks are so indented with fine lines, 
 that they do not take up the paint in a heavy daub from the flat cushion on which it 
 is spread with a brush, but in minute dots, so as to lay on the paint (somewhat thicker 
 than that of the house painter) in a congeries of little dots or teeth, with minute inter- 
 stices between. Applied in this way, the various pigments lie more evenly, are more 
 sightly, and dry much sooner than if the prominent part of the block which takes up 
 the colour were a smooth surface. The best kinds of floor cloth require from two to 
 three months for their production. 
 
 FODDER, a weight of 21 cwt., by which lead is sold in the north of England. 
 
 FUEL. On the measurement of heat, and the qualities of different kinds of coal, 
 I made an elaborate series of experiments, a few years ago, of which the following is an 
 outline. 
 
 The first and most celebrated, though probably not the most accurate apparatus for 
 measuring the quantity of heat transferable from a hotter to a colder body, was the 
 Calorimeter of Lavoisier and Laplace. It consisted of three concentric cylinders of tin 
 plate, placed at certain distances asunder ; the two outer interstitial spaces being filled 
 with ice, while the innermost cylinder received the hot body, the subject of experiment. 
 The quantity of water discharged from the middle space by the melting of the ice in it, 
 served to measure the quantity of heat given out by the body in the central cylinder. 
 A simpler and better instrument on this principle would be a hollow cylinder of ice of 
 proper thickness, into whose interior the hot body would be introduced, and which 
 would indicate by the quantity of water found melted within it the quantity of heat 
 absorbed by the ice. In this case, the errors occasioned by the retention of water among 
 the fragments of ice packed into the cylindric cell of the tin calorimeter, would be 
 avoided. One pound of water at 172° F., introduced into the hollow cylinder above 
 described, will melt exactly one pound of ice ; and one pound of oil heated to 172° will 
 melt half a pound. 
 
 The method of refrigeration, contrived at first by Meyer, has been in modern times 
 brought to great perfection by Dulong and Petit. It rests on the principle, that two 
 surfaces of like size, and of equal radiating force, lose in like times the same quantity 
 of heat when they are at the same temperature. Suppose for example, that a vessel of 
 polished silver, of small size, and very thin in the metal, is successively filled with dif- 
 ferent pulverized substances, and that it is allowed to cool from the same elevation of 
 temperature ; the quantities of heat lost in the first instant of cooling will be always 
 equal to each other ; and if for one of the substances, the velocity of cooling is double 
 of that for another, we may conclude that its capacity for heat is one half, when its 
 weight is the same ; since by losing the same quantity of heat, it sinks in temperature 
 double the number of degrees. 
 
 The method of mixtures. — In this method, two bodies are always employed; a hot 
 body which becomes cool, and a cold body, which becomes hot, in such manner that all 
 the caloric which goes out of the former is expended in heating the latter. Suppose 
 for example, that we pour a pound of quicksilver at 212° F., into a pound of water at 
 32° ; the quicksilver will cool and the water will heat, till the mixture by stirring ac- 
 quires a common temperature. If this temperature was 122°, the water and mercury 
 would have equal capacities, since the same quantity of heat would produce in an equal 
 
FUEL. 
 
 91 
 
 mass of these two substances equal changes of temperature, viz., an elevation of 90° in 
 the water and a depression of 90° in the mercury. But in reality, the mixture is found 
 to have a temperature of only 37^°, showing that while the mercury loses 1741 ) the 
 water gains only 5±° ; two numbers in the ratio of about 32 to 1 ; whence it is concluded, 
 that the capacity of mercury is gL of that of water. Corrections must be made for the 
 influence of the vessel and for the heat dissipated during the time of the experiment. 
 
 The following calorimeter, founded upon the same principle as that of Count Rum- 
 ford, but with certain improvements, may be considered as an equally correct instrument 
 for measuring heat, with any of the preceding, but one of much more general applica- 
 tion, since it can determine the quantity of heat disengaged in combustion, as well as 
 the latent heat of steam and other vapours. 
 
 (Scale about £ inch to the foot.) 
 
 It consists of a large copper bath, e, f, (Jig. 51.) capable of holding 100 gallons of 
 water. It is traversed four times, backwards and forwards, in four different levels, by 
 a zig-zag horizontal flue, or flat pipe d, c, nine inches broad and one deep, ending below 
 in a round pipe at c, which passes through the bottom of the copper bath e, f, and 
 receives there into it the top of a small black lead furnace b. The innermost crucible 
 contains the fuel. It is surrounded at the distance of one inch by a second crucible, 
 which is enclosed at the same time by the sides of the outermost furnace ; the strata 
 of stagnant air between the crucibles serving to prevent the heat from being dissipated 
 into the atmosphere round the body of the furnace. A pipe a, from a pair of cylinder 
 double bellows, enters the ash-pit of the furnace at one side, and supplies a steady but 
 gentle blast, to carry on the combustion, kindled at first by half an ounce of red-hot 
 charcoal. So completely is the heat which is disengaged by the burning fuel absorbed 
 by the water in the bath, that the air discharged at the top orifice g, has usually 
 the same temperature as the atmosphere. 
 
 The vessel is made of copper, weighing two pounds per square foot ; it is 5\ feet long, 
 11 wide, 2 deep, with a bottom 5\ feet long, and 1| broad, upon an average. Including 
 the zig-zag tin plate flue, and a rim of wrought iron, it weighs altogether 85 pounds. 
 Since the specific heat of copper is to that of water as 94 to 1000 ; the specific heat of 
 the vessel is equal to that of 8 pounds of water, for which, therefore, the exact correc- 
 tion is made by leaving 8 pounds of water out of the 600. or 1000 pounds vised in each 
 experiment. 
 
 In the experiments made with former calorimeters of this kind, the combustion was 
 maintained by the current or draft of a chimney, open at bottom, which carried off at 
 the top orifice of the flue a variable quantity of heat, very difficult to estimate. 
 
 When the object is to determine the latent heat of steam and other vapours, they may 
 be introduced through a tube into the top orifice g, the latent heat being deduced from 
 the elevation of temperature in the water of the bath, and the volume of vapour ex- 
 pended from the quantity of liquid discharged into a measure glass from the bottom 
 outlet c. In this case, the furnace is of course removed. 
 
 The heating power of the fuel is measured by the number of degrees of temperature 
 which the combustion of one pound of it, raises 600 or 1000 pounds of water in the 
 bath, — the copper substance of the vessel being taken into account. One pound of dry 
 
 N 2 
 
92 
 
 FUEL. 
 
 wood charcoal by its combustion causes 6000 pounds of water to become 20° hotter 
 For the sake of brevity, we shall call this calorific energy 12,000 unities. In like cir- 
 cumstances, one pound of Llangennoek coal will yield by combustion 11,500 unities 
 of caloric. One pound of charcoal after exposure to the air gives out in burning only 
 10,500 unities ; but when previously deprived of the moisture which it so greedily im- 
 bibes from the atmosphere, it affords the above quantity. One pound of Lambton's 
 Wall's-end coals, affords 8500 unities; and one of anthracite 11,000. 
 
 It must be borne in mind that a coal which gives off much unburnt carburetted hy- 
 drogen gas, does not afford so much heat, since in the production of the gas a great 
 deal of heat is carried off in the latent state. I have no doubt, that by this distillatory 
 process, from one-third to one-fourth of the total calorific effect of many coals is dissi- 
 pated in the air. But by means of such a furnace as the patent Argand invention of 
 Mr. C. W. Williams, the whole heat produceable by the hydrogen as well as the carbon 
 is obtained ; and it should be borne in mind that a pound of hydrogen in burning 
 generates as much heat as three pounds of carbon. 
 
 M. Berthier proposes to determine the proportion of carbon in coals and other kinds 
 of fuel, by igniting in a crucible a mixture of the carbonaceous matter with litharge, 
 both finely comminuted, and observing the quantity of lead which is reduced. For 
 every 34 parts of lead, he estimates 1 part of carbon, apparently on the principle, that 
 when carbon is ignited in contact with abundance of -litharge, it is converted into car- 
 bonic acid. Each atom of the carbon is therefore supposed to seize two atoms of 
 oxygen, for which it must decompose two atoms of litharge, and revive two atoms of 
 lead. Calling the atom of carbon 6, and that of lead 104, we shall have the following 
 ratio : — 6 : KM x 2 : : 1 : 34.66, being Berthier's proportion, very nearly. 
 
 On subjecting this theory to the touchstone of experiment, I have found it to be en- 
 tirely fallacious. Having mixed very intimately 10 grains of recently calcined char- 
 coal with 1000 grains of litharge, both in fine powder, I placed the mixture in a crucible 
 which was so carefully covered, as to be protected from all fuliginous fumes, and ex- 
 posed it to distinct ignition. No less than 603 grains of lead were obtained ; whereas 
 by Berthier's rule, only 340 or 346.6 were possible. On igniting a mixture of 10 grains 
 of pulverized anthracite from Merthyr Tydfil, with 500 grains of pure litharge (pre- 
 viously fused and pulverized), I obtained 380 grains of metallic lead. In a second 
 similar experiment with the same anthracite and litharge, I obtained 450 grains of lead ; 
 and in a third only 350 grains. It is therefore obvious that this method of Berthier is 
 altogether nugatory for ascertaining the quantity of carbon in coals, and is worse than 
 useless for judging of the calorific qualities of different kinds of fuel. 
 
 In my researches upon coals, I have also made it one of my principal objects to de- 
 termine the quantity of sulphur which they may contain ; a point which has been 
 hitherto very little investigated in this country at least, but which is of great conse- 
 quence, not only in reference to their domestic combustion, but to their employment 
 by manufacturers ■ of iron and gas. That good iron cannot be produced with a sul- 
 phureous coal, however well coked, has been proved in France by a very costly experi- 
 ence. The presence of a notable proportion of sulphur in a gas coal is most injurious 
 to the gaseous products, because so much sulphuretted hydrogen is generated as to re- 
 quire an operose process of washing or purification, which impoverishes the gas, and 
 impairs its illuminating powers by the abstraction of its olefiant gas, or bicarburetted 
 hydrogen. In proof of this proposition, I have only to state the fact, that I found in 
 a specimen of coal gas as delivered from the retorts of one of the metropolitan compa- 
 nies, no less than 18 per cent, of olefiant gas, while in the same gas, after being passed 
 through the purifiers, there remained only 1 1 per cent, of that richly-illuminating gas. 
 By using a gas-coal, nearly free from sulphur, such as No. 4. in the subjoined list, I 
 think it probable that 10 per cent, of more light may be realized than with the common 
 more sulphureous coal. This is an important circumstance which the directors of gas- 
 works have hitherto neglected to investigate with analytical precision, though it is one 
 upon which their success and profits mainly depend. 
 
 How little attention indeed has been bestowed upon the sulphureous impregnation 
 of pit-coal may be inferred from the fact that one of our professional chemists of note, 
 in a public report, upon a great commercial enterprize, stated that a certain coal analyzed 
 by him was free from sulphur, which coal I found by infallible chemical evidence to 
 contain no less than 7 per cent, of sulphur, being about the double of what is contained 
 in English coals of average quality. The proportion of sulphur may in general be in- 
 ferred from the appearance and quantity of the ashes. If these be of a red or ochrey 
 colour, and amount to above 10 per cent., we may be sure that the coal is eminently 
 sulphureous. The coal above referred to afforded from 15 to 16 per cent, of ferrugin 
 ous ashes I believe that sulphur exists in coal generally, though not always in the state 
 of pyrites, either in manifest particles, or invisibly disseminated through their substance. 
 The readiest method of determining rigidly the quantity of sulphur in any compound. 
 
FUEL, GRANT'S PATENT. 93 
 
 is to mix a given weight of it with a proper weight of carbonate of potassa, nitre, and 
 common salt, each chemically pure, and to ignite the mixture in a platinum crucible. 
 A whitish mass is obtained, in which all the sulphur has been converted into sulphate 
 of potassa. By determining with nitrate of baryta the amount of sulphuric acid pro- 
 duced, that of the sulphur becomes known. By means of this process applied to dif- 
 ferent samples of coals, I obtained the following results : — 
 
 Gas Sulphur in Gas Sulphur in 
 
 Coals. 100 parts. Coals. 100 parts. 
 
 No. 1 - - - - 3.00 No. 5 - - - - 2.50 
 
 2 3.90 6 5.20 
 
 3 2.42 7 3.40 
 
 4 3.80 8 3.50 
 
 Coals for puddling cast iron, Sulphur in 
 
 to be converted into steel, 100 parts. 
 
 No, 1, hard foliated or splent coal, specific gravity 1.258 0.80 
 
 2, ditto 1.290 0.96 
 
 3, ditto - - 1.273 3.10 
 
 4, cubical and rather soft - 1.267 0.80 
 
 The last coal being rich in bitumen, would prove an excellent one for the production 
 of a pure coal gas. See Pitcoal. 
 
 FUEL, ECONOMY OF. In the report of the Transactions of the Institution of 
 Civil Engineers for February, 1 838, the results of exact comparisons between the per- 
 formance of different steam-engines exhibit this economy in a remarkable manner. It 
 is there shown that a condensing engine of the most perfect construction, and in perfect 
 condition, of the common low pressure crank-kind, not working expansively, performs 
 a duty of not more than 20 or 21 millions of lbs. raised one foot high, by 90 or 94 lbs. 
 of coal ; or ten lbs. of coal per horse power per hour. 
 
 The following table exhibits the relative value of different engines in lbs. of coal per 
 horse power per hour : — 
 
 Cornish Pumping Engine - - -1*57 
 
 Bolton and Watt's Single Engine - - 4 82 
 
 Cornish Double Engine - 3-25 
 
 Bolton and Watt's Double Engine - - 10-5 
 
 The greatest duty performed by the measured bushel of 84 lbs. was 86| millions of 
 lbs. There was raised by the Duel Towan engine in Cornwall 1085 tons (of water) 
 one foot high for one farthing. Hence the weight of a man (1| cwt.) would be raised 
 ten miles for one penny ! 
 
 In order to raise steam with economy, the surface of water in the boiler, exposed to 
 the fire, ought not to be less than 10 square feet per horse power ; but the usual allow- 
 ance in Lancashire is only 1\ ; and by Messrs. Boulton and Watt, 5 square feet. 
 
 The values of the mean of the Cornish, Warwick, London, Lancashire, and loco- 
 motive experiments, as reported by Mr. Josiah Parkes, were respectively 21, 18, 13^, 
 and 10 cubic feet of water evaporated by 112 lbs. of coals, from water heated to 
 212° F. 
 
 FUEL, GRANT'S PATENT. This fuel is composed of coal-dust and coal-tar 
 pitch ; these materials are mixed together, under the influence of heat, in the following 
 proportions : — 20 lbs. of pitch to 1 cwt. of coal-dust, by appropriate machinery ; 
 consisting of crushing-rollers for breaking the coal in the first instance sufficiently 
 small, so that it may pass through a screen the meshes of which do not exceed a quarter 
 of an inch asunder ; 2dly, of mixing-pans or cylinders, heated to the temperature of 
 220°, either by steam or heated air ; and, 3dly, of moulding machines, by which the 
 fuel is compressed, under a pressure equal to five tons, into the size of a common brick ; 
 the fuel bricks are then whitewashed, which prevents their sticking together, either in 
 the coal bunkers or in hot climates. The advantages of Grant's fuel over even the 
 best coal may be stated to consist, first, in its superior efficacy in generating steam, 
 which may be thus stated' — 200 tons of this fuel will perform the same work as 300 
 tons of coal, such as are generally used; secondly, it occupies less space ; that is to say, 
 500 tons of it may be stowed in an area which will contain only 400 tons of coal ; 
 thirdly, it is used with much greater ease by the stokers or firemen than coal, and it 
 creates little or no dirt or dust, considerations of some importance when the delicate 
 machinery of a steam-engine is considered; fourthly, it produces a very small propor- 
 tion of clinkers, and thus it is far less liable to choke and destroy the furnace bars and 
 boilers than coal ; fifthly, the ignition is so complete that comparatively little smoke, 
 and only a small quantity of ashes, are produced by it ; sixthly, from the mixture of 
 the patent fuel, and the manner of its manufacture, it is not liable to enter into 
 spontaneous ignition. 
 
94 
 
 GAS-LIGHT. 
 
 G. 
 
 GALVANO- PLASTIC is the German name of Electro- 
 Metallurgy. 
 
 GARANCINE, an extract of madder by means of sulphuric 
 acid, prepared in France. 
 
 GAS-LIGHT. Since the former edition of this work I 
 have received from 
 
 Mr. Hedley, an 
 engineer of great 
 eminence and ex- 
 perience, plans and 
 drawings of gas 
 works and of ap- 
 paratus of the 
 most approved and 
 modern construc- 
 tion, and on the 
 very largest scale 
 as to extent of 
 business or manu- 
 facture ; also plans 
 and drawings of 
 a gas work on a 
 smaller scale, with 
 its corresponding 
 apparatus. In the 
 first, or large work, 
 purification by wet 
 lime, before des- 
 cribed, is used ; in 
 the latter, by dry 
 lime. 
 
 The large work 
 referred to is cal- 
 culated for and is 
 arranged to con- 
 tain 400 retorts, 
 12 wet-lime puri- 
 fiers, & 2 washers ; 
 1 2 large double 
 or telescopic gas- 
 holders, capable of 
 storing 1,000,000 
 cubic feet of gas ; 
 and coal stores ca- 
 pable of holding 
 10,000 tons of coal. 
 
 The smaller work 
 is calculated for 
 and will contain 40 
 retorts, 2 dry-lime 
 purifiers, and a 
 wash vessel ; 2 
 gasholders capable 
 of storing 50,000 
 cubic feet of gas ; 
 and coal stores 
 sufficient for 1000 
 tons of coal. 
 
 Fig. 52. is the 
 side elevation 
 (front view) of 
 a gas work capa- 
 ble of containing 
 400 retorts, and 
 all their depend- 
 encies. 
 
 52 
 
GAS-LIGHT, 
 
 9o 
 
 Fig. 53. is the plan of the retort house, coal stores, tanks, gas-holders, &c, on the 
 largest scale and most approved form, viz., A, the retort house, 300 feet long, 56 feet 
 wide ; B, retort beds ; C, chimney stack ; D, flues ; E, hydraulic mains ; F, coal 
 stores, each 300 feet long, 30 feet wide ; G, condensers ; H, engine houses ; J, wash 
 
96 GAS-LIGHT. 
 
 XG TlV *\ PUriR xT S a ? d c f. nnections ; L > Kme store and mixing tub; M smiths' 
 and fitters' shop; N, refuse lime pits ; O, meter houses ; P, tar tank ; Q, tanks^as- 
 holders bndges columns, valves, and connections; R, governors ; S, coke lofes • 
 T, inlet pipes; V, outlet pipes ; W, house and offices ; xf stores ' 
 
GAS-LIGHT. 
 
 97 
 
 Fig. 56. Elevation of an upright air condenser, consisting of 5 chambers, with a 
 series of 10-inch pipes. 
 
 56 
 
 i4 fen 
 
 Sj 
 
 S5' 
 
 I LJ 
 si ^ 
 
 f 'r J 1 
 ! «Sj' « 
 
 JSP f 
 
 d> ' 
 
 3W 
 
 
 ■ « 
 
 r i 
 
 n 
 
 5 r 
 
 Si 
 
 3 c 
 
 ' 1 
 
 I 
 
 
 M 
 
 
 rc j 
 
 
 |« — >; 
 
 
 
 
 
 
 2^. 57. Elevation of a double or telescopic gas-holder, of a modern and approved 
 form, with part of tank. 
 
 57 
 
98 
 
 GAS-LIGHT. 
 
 Fig, 58. End elevation and plan of air condenser ; A, end elevation ; B, plan. 
 
 Fig. 59. Set of 3 wet -lime purifiers and wash- vessels in elevation and section, with 
 feed-heads, agitators, valves, and connections, raised for the lime liquor to run from 
 one purifier to the next below it, and ultimately into the refuse lime-pits, viz. A, 
 section of wash vessel j B, section of purifier ; C, elevation of purifier. 
 
 58 59 
 
 i 
 
GAS-LIGHT. 99 
 
 Fig. 60. Front elevation of gas works on a smaller scale, where dry lime is used. 
 
 O 2 
 
100 
 
 GAS-LIGHT. 
 
 Fig, 61. Plan of gas works, consisting of, viz. : A, retort house; B, retort beds; 
 C, chimney stack ; D, flue ; E, hydraulic main ; F, coal store : G, lime store ; H, 
 washer and purifiers ; J, store ; K, tar-tank ; L, horizontal condenser laid on the 
 ground ; M, inlet pipe ; N, outlet pipe ; O, tanks and gas-holders ; P, meter and 
 governor ; Q,, smiths' shop ; R, office ; S, coke store. 
 
 61 
 
GAS-LIGHT. 
 
 101 
 
 Fig. 62. Elevations and sections of dry-lime purifiers ; A, longitudinal elevation ; 
 B, ditto section ; C, transverse elevation ; D, ditto section. 
 
 n c 
 
 62 
 
 1 - 
 
 ■ . ^ D 
 
 
 
 D 
 
 
 §! 
 
 
 — 2 — 
 
 
 D 
 
 ta- 
 
 5L. . 
 
 
 c= 
 
 
 
 
 
 
 
 
 
 4 
 
 I am well convinced that a distribution and arrangement of gas-works, combining 
 effectiveness, economy, convenience, and elegance, at all equal to the preceding, have 
 never before met the public eye, in this or any other country. 
 
 Trials of, and Experiments on, various Kinds of Coal as regards the Production of Gas 
 from each, and its Quality or Illuminating Power ; by Joseph Hedley, Esq., Con- 
 sulting Gas Engineer, London. 
 
 Note In all the experiments the gas was passed through a governor, on a pressure of 5-10ths of an 
 
 inch. 
 
 10. 11. 1% 13. 14. 15. 16. 17. 
 
 Name and 
 Description of 
 Coal. 
 
 an Aperture or Tube with- 
 Burner, 2-10ths of an Inch, 
 full on. — Height of Flame. 
 
 onsumed per Hour by ditto. | 
 
 et Hole, 28th of an Inch Di- 
 , turned full on. — Height of 
 
 onsumed per Hour by ditto. 
 
 * Flame, restricted to 4 Inches 
 »h, consumed per Hour. 
 
 Equal in 
 Illuminating 
 Power to 
 
 with 20 Holes; outer Diameter 
 s of an Inch ; inner ditto 
 
 an Inch ; Holes 40th of an 
 Diameter ; Distances apart, 
 
 of an Inch ; full Illumin- 
 Power equal to 12 Candles ; 
 led per Hour. 
 
 with 30 Holes; outer Diameter 
 ;h ; inner ditto 7 -8th of an 
 Holes 40th of an Inch Di- 
 ; Distances apart, l-10th of 
 h ; full Illuminating Power 
 :o 25 Candles ; Consumption 
 
 Specific Gravity. 
 
 oduction of Gas from 20 lbs. 
 tl, and Duration of Charge. 
 
 t End of 1st Half-hour. 
 
 2d Half-hour. 
 
 3d ditto. 
 
 4th ditto. 
 
 5th ditto. 
 
 6th ditto. 
 
 
 
 o 
 
 a 
 
 
 u 
 
 a 
 
 
 
 
 
 
 S3 
 
 
 
 
 
 
 
 
 g-fi 
 
 j=§5 
 
 o 
 
 in 
 
 o 
 
 "So 
 s 
 
 
 'i-l 
 6-1 
 
 1-1 
 
 atii 
 
 fell sIS. 
 
 
 •tal 
 
 0 
 
 
 
 
 
 
 
 
 
 
 33 
 
 
 
 
 < 
 
 < 
 
 
 h* 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 *e 
 
 o . 
 
 
 
 
 „ 
 
 
 
 
 
 Inches. 
 
 3 v 
 
 
 11 
 
 i| 
 
 Candles. 
 
 Cubic Feet. 
 
 Cubic Feet. 
 
 Z c 
 
 1,5 
 
 a 
 
 1 1 
 
 
 'Z " 
 - ? 
 
 - D 
 
 n 
 
 - j 
 
 = r ^ 
 
 
 
 
 C 
 
 
 
 
 
 
 
 
 X 
 
 
 
 
 
 
 _ ft 
 
 Lismahago, or 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 Glasgow Can- 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 nel 
 
 21 to 22 
 
 12 
 
 9 
 
 12-1 
 
 7-2 
 
 2-77 
 
 2-3 
 
 3-9 
 
 •757 
 
 101 
 
 
 59 
 
 27 
 
 22 
 
 11 
 
 2 
 
 
 Newcastle Coal 
 
 18 
 
 16 
 
 
 16-2 
 
 11-1 
 
 1-75 
 
 5- 
 
 7-5 
 
 •475 
 
 104 
 
 3 
 
 50 
 
 20 
 
 18 
 
 15 
 
 15 
 
 6 
 
 Welsh Cannel - 
 
 22 
 
 11 
 
 9 
 
 12-1 
 
 7-1 
 
 3- 
 
 2* 
 
 3- 
 
 •757 
 
 j 102 
 
 2 
 
 50 
 
 50 
 
 20 
 
 2 
 
 
 
 Pelaw, Newcas- 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 tle Coal 
 
 18 
 
 16 
 
 
 16-1 
 
 ii-i 
 
 1-75 
 
 5- 
 
 7*5 
 
 •4 14 
 
 ' 102 
 
 
 29 
 
 20 
 
 17 
 
 16 
 
 14 
 
 6 
 
 Pelton, ditto - 
 
 18 
 
 16 
 
 n 
 
 16-2 
 
 11-2 
 
 1-73 
 
 6' 
 
 7-5 
 
 ■157 
 
 
 
 28 
 
 . 
 
 VJ 
 
 16 
 
 14 
 
 6 
 
 BickerstafF, Li- 
 
 
 
 
 
 
 
 
 
 j 102 
 
 I 
 
 
 
 
 verpool ditto - 
 
 19 
 
 11 
 
 
 16-2 
 
 1*1-1 
 
 2-04 
 
 4-6 
 
 6-5 
 
 •17." 
 
 102 
 
 
 30 
 
 24 
 
 18 
 
 16 
 
 10 
 
 4 
 
 Wigan Cannel - 
 Blenkinsopp, 
 Carlisle Coal - 
 
 22 
 27 
 
 12 
 16 
 
 a 
 
 13-1 
 151 
 
 7-2 
 11-1 
 
 3- 
 
 1-87 
 
 2- 
 4-6 
 
 3- 
 7- 
 
 ■(]()( 
 '521 
 
 100 
 ' IOC 
 
 
 " 
 
 28 
 
 30 
 24 
 
 18 
 18 
 
 10 
 
 18 
 
 4 
 10 
 
 2 
 
 Neath Coal 
 
 18 
 
 16 
 
 7* 
 
 19-1 
 
 12-1 
 
 1-75 
 
 5-22 
 
 7-5 
 
 •468 100 
 
 3 
 
 126 
 
 21 
 
 20 
 
 l 1 
 
 12 
 
 7 
 
 Note. —The candle here used was a composition candle, with plaited wick, requiring no snuffii 
 at least one-third more light than mould tallow candles. 
 
 , giving 
 
102 
 
 GAS-LIGHT. 
 
 Attention to the preceding tabular statement of experiments is important, as exhibit- 
 ing several very important facts, particularly interesting at this moment to the science 
 of gas-lighting, and now for the first time made public. 
 
 It will not fail to be observed by these experiments that all the coals, produced nearly 
 equal quantities of gas, notwithstanding the variable characters and qualities of the 
 coal. The greatest quantity produced being at the rate of 1 1 '648 cubic feet per ton of 
 20 cwt., the smallest 1 1 -200 cubic feet. All these experiments were performed with the 
 greatest care, and under precisely similar circumstances as to pressure, manufacture, &c. 
 &c. The time in which the quantity of gas is produced from the several coals varies con- 
 siderably, and deserves notice, as it most materially affects the economy of production 
 — that coal being the most valuable, all other things being alike, which yields or gives out 
 its gas in the shortest time ; and particular attention is claimed to this fact. For the 
 more ready reference to the table the columns are numbered. No. 11. exhibits this 
 difference, and it will also be seen by this column that the time varies as the quality of 
 the coal, the best coal yielding its gas in two hours, and the worst in three hours. 
 
 Another most important, material, and interesting fact is established by these experi- 
 ments — that the flow of gas is as its density — demonstrated by the variation in the 
 heights of the flames, as shown in column No. 1. being 18 inches in the inferior gases 
 to 22 inches in the superior ; whilst the quantity of gas required to supply these flames 
 is in the inverse ratio of their heights, the longer flame requiring but twelve cubic feet 
 to maintain it, when the shorter flame, from the inferior gas, required sixteen cubic feet. 
 See column No. 2. 
 
 Remarkable as this difference in the heights of the flames and the consumption is, 
 it is not so great as the difference caused by the quality or illuminating power of the 
 several gases, shown by columns Nos. 5 and 6. ; where it will be seen that the consump- 
 tion of the best gas per hour was only 7 5 ths of a cubic foot, and its light was equal to 3 
 candles, whilst that of the worst gas was j§ths of a cubic foot, and its light equal only 
 to 1 '15 candles, or nearly, the best to the worst, as 1 to 3. 
 
 The next column, No. 7., exhibits similar results as to the superior value or illu- 
 minating power of one gas over another. In this case an argand burner was used. 
 The best gas required only two feet to be equal to twelve candles, whilst the inferior 
 required five feet to be equal to the same. 
 
 And in column No. 8., in which another and superior argand burner was used, the 
 best gas required only three feet to be equal to twenty-five mould candles, whilst the 
 inferior required seven and a half feet : from this it results that the 7^ cubic feet of 
 inferior gas, to be equal to the 3 feet of good gas, should have given light equal to 
 sixty-two and a half candles, whereas they only gave light equal to twenty-five candles; 
 so great is the difference in the qualities of gas for producing light. 
 
 Whilst on the subject of the illuminating power and the value of one gas over 
 another, it will not fail to be observed, by the table, that another great difference also 
 exists, caused by the use of particular burners ; as, for example, the best gas in column 
 No. 5., where the single jet was used, required seven tenths of a cubic foot to be 
 equal to three candles, whilst the same gas in column No. 7., where a 20-hole 
 argand burner was used, required only two feet to be equal to twelve candles ; and in 
 column No. 8., where a 30-hole argand burner was used, only three feet were re- 
 quired to be equal to twenty-five candles ; demonstrating the fact that a great and 
 extraordinary improvement in the quantity of illuminating power is effected by the 
 simple increase or enlargement of the burner, affording, where great light in one 
 position is required, a most extraordinary economy in the use of gas, shown in fact 
 practically by the recent introduction of the celebrated " Bude " light, patented by Mr. 
 Goldsworthy Gurney. 
 
 Tabular Statement, deduced from the foregoing Experiments, showing the Cost of 
 Candles to produce as much Light as 9,000 Cubic Feet of Gas would afford, being 
 the Product of One Ton of Coal. (The candles are moulds, 6 to the pound, 9 inches 
 long, and each candle is calculated to burn 9| hours. Cost of candles 1\d. per 
 pound, or 7s. 6d. per dozen pounds.) 
 
 Candles would cost, to be 
 equivalent to 
 
 Where a Single 
 Jet Burner is 
 used. 
 
 Where a 20-hole 
 Argand Burner 
 is used. 
 
 Where a 30-hole 
 Argand Burner 
 is used. 
 
 Where a Bude 
 Burner is used, 
 according to 
 Statement of 
 Company. 
 
 
 £ s. d. 
 
 £ s. d. 
 
 ' £ s. d. 
 
 £ s. d. 
 
 Common coal gas 
 
 10 18 6 
 
 15 15 8 
 
 21 18 0 
 
 59 2 7 
 
 Good do. 
 
 25 18 4 
 
 39 9 6 
 
 54 16 7 
 
 148 0 9 
 
GAS-LIGHT. 103 
 
 Table, also deduced from the foregoing, showing the Cost of Gas at the several 
 Prices undermentioned, and equivalent to 100 lbs. of Mould Candles, costing 
 31. 2s. 6d. 
 
 Description 
 of Gas. 
 
 If burnt 
 
 in a 
 Single Jet 
 Gas equal 
 to 100 lbs. 
 of Mould 
 Candles 
 
 Gas would cost at 
 per thousand 
 Cubic Feet. 
 
 If burnt 
 
 in a 
 20-hole 
 Argand 
 Burner, 
 Gas equal 
 to 100 lbs. 
 of 
 
 Candles. 
 
 Gas would cost at 
 per thousand 
 Cubic Feet. 
 
 If burnt 
 
 in a 
 30-hole 
 Argand 
 Burner, 
 Gas equal 
 to 100 lbs. 
 of 
 
 Candles. 
 
 Gas would cost at 
 per thousand 
 Cubic Feet. 
 
 Cotfimon 
 Good - 
 
 Cub. feet. 
 
 5s. 
 
 7s. 
 
 9s. 
 
 Cub. feet. 
 
 5s. 
 
 7s. 
 
 9s. 
 
 Cub. feet. 
 
 5s. 
 
 7s. 
 
 9s. 
 
 2,687 
 1,072 
 
 s. d. 
 13 5 
 5 4 
 
 s. d. 
 18 9 
 7 5 
 
 s. d. 
 24 2 
 9 7 
 
 1,781 
 712 
 
 s. d. 
 8 10 
 3 6 
 
 s. d. 
 12 5 
 4 11 
 
 s. d. 
 16 0 
 6 4 
 
 1,282 
 513 
 
 s. d. 
 6 5 
 2 7 
 
 s. d. 
 8 11 
 3 7 
 
 s. d. 
 11 6 
 4 7 
 
 In the brief description of the meter given in the Dictionary, I omitted to state, 
 that this most ingenious scientific contrivance for measuring aeriform or gaseous fluids 
 as they flow through pipes is the invention of Samuel Clegg, Esq., Civil Engineer, of 
 London, Manchester, Liverpool, Birmingham, Chester, Bristol, &c. &c, in all which 
 places he has erected gas-works. To this gentleman's genius and skill the public 
 are mainly indebted for many valuable improvements in the application of gas from 
 coal to purposes of illumination. 
 
 Brought up in the great engineering establishment of Messrs. Boulton and Watt, 
 at Soho, near Birmingham, he became connected with Mr. Win. Murdoch, who most 
 undoubtedly was the author and originator of gas- lighting, as the evidence given before 
 a Committee of the House of Commons in the year 1809 abundantly verified. He 
 demonstrated that the light produced from gas was superior in economy to all other 
 modes of artificial illumination; and by that evidence, though so long back as 1809, 
 it will be seen that all the information of the present day was even then known to him, 
 clearly pointed out, and illustrated by his experiments, which strangely contrasted 
 with the statements put forward by the parties then attempting to introduce this mode 
 of lighting into the metropolis. All the ephemeral plans of those parties have, how- 
 ever, long since disappeared, or nearly all. One, unfortunately, remains, and that a 
 most unlucky one — the unprofitable manufacture of coke in gas-making — an article 
 worthless in the scale of value, which should never have been sought for. Messrs. 
 Watt and Murdoch predicted that when the parties became incorporated by Par- 
 liament, they would resort to their apparatus, notwithstanding their repudiation of it 
 at the time, alleging their own schemes to be so much superior ; and they verified this 
 prediction a very few years afterwards by engaging the services of Mr. Clegg, to extri- 
 cate them from their manifold and egregious errors. He began by introducing the very 
 apparatus of Messrs. Murdoch and Watt, so inconsiderately condemned by them. 
 
 Mr. Clegg put up the^rs^ gas-holder ever erected in London. 
 
 To Mr. Clegg is due also the introduction of lime for the purification of the gas, 
 without which gas-lighting would to this day have afforded little comfort and 
 economy. The hydraulic main, for separating the gas making from the gas made, 
 valves, lutes, and many other admirable contrivances, are peculiarly due to Mr Clegg. 
 But the crowning performance of all his inventions, was that for measuring out the gas 
 to the several parties requiring it exactly according to their demands. The manu- 
 facture of gas having by this time been so far mechanically perfected as to be brought 
 to our doors, it became at once apparent that some contrivance should be found by the 
 use of which every person might consume as much or as little gas as he pleased, paying 
 only for what he really used, thus making science subservient to fair dealing. 
 
 Mr. Clegg took out a patent for the gas-meter about the year 1814; but great as 
 its merits were, he soon found that serious difficulties remained to be overcome, in in- 
 ducing parties to support and encourage its use, even where their interests should have 
 prompted them to adopt it. Mr. Clegg had, however, fortunately associated with him, 
 towards the completion of the apparatus, Mr. Samuel Crosley; and by their joint 
 labours it acquired its present precision. 
 
 The value of the meter is primarily to the gas companies, next to the public. By 
 its use, the gas companies are enabled to supply gas to all places where light is re- 
 quired, at a rate proportioned to its just value. The public thereby see the economy 
 afforded by gas over candles, oil, or other material ; but they gain also in another most 
 important way — by the use of the meter, gas companies, being duly paid, are enabled 
 to reduce the price of gas, and yet realise equal profits, thus bringing it within the reach 
 
104 
 
 GAS-LIGHT. 
 
 of a much larger class of the community; and it is a well established fact that in 
 towns where gas is sold by meter, gas companies can and do sell at nearly one half 
 the price they otherwise could do. 
 
 Reduction of price increases demand ; increased demand increases profits ; increased 
 profits again enable prices to be reduced ; and again, reduced prices increase the 
 demand, thus benefiting reciprocally companies and consumers. 
 
 Notwithstanding, however, all these advantages, there are not wanting persons who 
 have set up an outcry against the use of the meter, by impugning its accuracy, and 
 accusing the gas companies with fraud in charging by it. It would be idle to follow 
 these parties in their baseless allegations. An action for pirating it was brought and 
 tried in the Court of King's Bench, in which not only the novelty of the machine 
 was fully established, but its accuracy and usefulness proved by the ablest mathe- 
 maticians, mechanicians, and chemists of the day ; and a verdict in its favour obtained. 
 Subsequently very large damages have been given for the infringement — in one case 
 as much as 5000/., and in another, in the Court of Chancery, a decree was made refer- 
 ring it to the Master, to take an account of the profits made by the use of the meter ; 
 this is not yet finally settled, the Master's report finding 6000/. to be due ; but this is 
 excepted to by the parties infringing : the Chancellor, however, allowed the exceptions 
 to be argued, only on payment by the infringers of 4000/. into court to meet the pa- 
 tentee's law costs. These exceptions have no reference whatever to the question of the 
 accuracy of the meter, but are simply as to whether the advantages of the meter were 
 as great as allowed by the Master. 
 
 The patent for the meter expired about the year 1828 ; since that period numerous 
 competitors have commenced making the machine. 
 
 Mr. Clegg has recently obtained a patent for a dry gas-meter, of which the following 
 are its advantages and construction, as described by the very meritorious inventor : 
 
 1. Working without water. 
 
 2. Working without membranes or valves. 
 
 3. Working without requiring the least pressure. 
 
 4. Working without interference with the perfect steadiness of the lights. 
 
 5. Registering more accurately than any other meter. 
 
 6. Occupying only one-tenth of the space of the common meters. 
 
 7. Being subject to little or no wear and tear. 
 
 8. And being cheaper. 
 Prices. — For plain meters, — 
 
 £ s. d. 
 
 Three-light meter .... 1120 
 
 Six-light do 2 4 0 
 
 Twelve-light do 3 3 0 
 
 The highest numbers will be still cheaper in proportion. 
 
 Ornamental meters, appearing like handsome time-pieces, for halls, living-rooms, 
 committee-rooms, offices, counting-houses, &c, are charged extra, at ten shillings each 
 and upwards, according to pattern. 
 
 Description of Clegg's patent dry Gas-meter. 
 
 The two figs. 63, 64. are half the full size of the apparatus, and the letters of reference 
 are the same in both. 
 
 B, B,fig. 63., represents a cylindrical vessel, about three inches and three quarters 
 diameter, and four inches deep, being the dimensions of a meter capable of measuring 
 gas for three burners, called a three-light meter. In this vessel are two glass cylinders 
 F, F, connected together by the bent tube d. The cylinders being perfectly exhausted 
 of air, and half filled with alcohol, are made to vibrate on centres e and e, and are 
 balanced by the weighty 
 
 This instrument accurately indicates the excess of heat to which either cylinder may 
 be exposed, upon the principle of Leslie's differential thermometer. 
 
 C is a hollow brass box, called the heater, about four inches long, and half an inch 
 broad, projecting out of the meter about one inch. At a issues a small jet of gas, 
 which, when inflamed, gives motion to the cylinders. 
 
 The gas enters the meter by the pipe A, and circulates throughout the double caseB : 
 having passed round the case B, a portion of it enters the top of the box C, by the pipe 
 D, and passes out again at the bottom by the tube c, into the meter ; the rest of the 
 gas enters the body of the meter through holes in the curved faces of the hoods EE, 
 and, after blowing on the glass cylinders, passes to the burners by the outlet pipe. 
 
 To put the meter in action, let the jet a be lighted about an hour before the burners 
 are wanted. In most cases this jet will be lighted all day as a useful flame. The 
 
GAS-LIGHT. 
 
 105 
 
 hole a is so situated on the box C, that whatever be the size of the jet, a fixed tem- 
 perature is given to the box, that temperature depending on the quantity of flame in 
 
 64 63 
 
 contact with the box, and not at all on the length of the jet. The jet being lighted, 
 and the box C thereby heated, the gas which passes through it is raised to the same 
 temperature, and, flowing out at the tube c, impinges on the glass cylinder which 
 happens for the time to be the lowest ; the heated gas soon raises a vapour in the 
 lower cylinder, the expansion of which drives the liquid into the upper one, until it 
 becomes heavier than the counterpoise f, when the cylinders swing on their centre, the 
 higher one descends, and comes in the line of the current of hot gas, and the lower one 
 ascends ; the same motion continues as long as the jet a burns. The same effect on 
 the cylinder is maintained, however the outward temperature may change, by the 
 cold gas, which, issuing from the curved side of the hood EE, impinges on the upper 
 cylinder, and hastens the condensation of the vapour which it contains. 
 
 The cold gas and the heater vary in temperature with the room, and thus counteract 
 each other. 
 
 The lighting of the jet a is essential to the action of the meters ; in order to insure 
 this, the supply of gas to the burners is made to depend on it in the following manner. 
 The pipe G, by which the gas leaves the meter, is covered by a slide valve, which is 
 opened and shut by the action of the pyrometer g ; the pyrometer is in communication \ 
 with and receives heat from the jet, and opens the valve when hot, closing it again ' 
 when cold. 
 
 The speed at which the cylinders vibrate is an index of the quantity of heat com- 
 municated to them, and is in exact proportion to the quantity of gas blowing on them 
 through the pipe c and curved side of the hoods EE. 
 
 The gas passed through the heater is a fixed proportion of the whole gas passing the 
 meter ; therefore the number of vibrations of the cylinders is in proportion to the gas 
 consumed. 
 
 A train of wheel-work, with dials similar to that used in the common meter, regis- 
 ters the vibrations. 
 
 Simplicity, accuracy, and compactness, are the most remarkable features of this 
 instrument, and the absence of all corrosive agents will insure its durability. 
 
 P 
 
106 
 
 GAS-LIGHT. 
 
 Directions for fixing and using Clegg's patent dry Gas-meters. 
 
 Choose a situation for fixing the meter, where the small jet of flame will be of the 
 greatest use, such as an office-desk or counter, taking care to screw the same firm and 
 level on its base. When the jet at the top of the meter is required to be kept con- 
 stantly burning as a useful flame, press in the brass knob at the front of the meter, and 
 before lighting the burners pull it out ; when the small flame is not required, let it be 
 lighted about an hour before you want the burners lighted. Adjust the size of the 
 small flame at pleasure by the screw b. 
 
 On the back of each meter is marked the number of lights it will supply. 
 
 The inlet and outlet pipes are marked at the bottom of the meter. 
 
 The quantity of gas consumed is recorded by the index in the usual way. 
 
 For testing Clegg's patent dry Gas-meters. 
 
 Pass the gas through two meters at least, and take the mean. Vary the number of 
 lights at pleasure, not exceeding the number marked on the meter, and when one or 
 two hundred cubic feet of gas have been consumed, compare the indices. 
 
 These meters are not for measuring small fractional parts ; but taking the average 
 for any periodical consumption, are more accurate than any other meter. 
 
 Mr. Thomas Edge, of Great Peter Street, Westminster, has contrived the following 
 meter, of which drawings are annexed. 
 
 Fig. 65. is a front view of a three-light meter, the front plate being removed, and 
 some of the parts shown in section 65. 
 
 Fig. 66. is a transverse section of the same. 
 
 The gas enters at a into the small chamber b, in the bottom of which is a lever 
 valve (part of Mr. Edge's patent improvements), moving upon its axis and attached 
 by the rod to a metal float c, which in the present drawing is buoyant. The object 
 of this arrangement is to intercept the passage of the gas into the meter, unless a 
 sufficient quantity of water is in it, that being necessary to its proper action ; the 
 gas then passes through the inverted syphon or tunnel into the convex cover, whence 
 it passes into the chambers of the drum. 
 
 Another of Mr. Edge's improvements consists in the cutting down of this syphon pipe 
 or tunnel to the proper water level, and connecting the bottom of it to a waste water- 
 box, into which any surplus water must fall. The importance of this precaution will be 
 seen on investigating the drum, as an excessive height of the water will materially 
 interfere with the measurement, the quantity of gas delivered per revolution being 
 considerably less. This, in connection with the lever valve and float, confines the 
 
GAS-LIGHT. 107 
 
 variation of the water levels within such narrow limits, that the measurement may be 
 considered perfectly just on all occasions. 
 
 The last patent by Mr. Edge is for an improved 
 Index, which is composed of a series of moving 
 dials, with 10 figures upon each, one figure only 
 appearing of each series at a time. 
 
 This contrivance is very ingenious, and will no 
 doubt be applied to other machines, where indexes 
 (indices) of quantity are required. 
 
 Recurring to Mr. Clegg, he is also the inventor 
 of an instrument of great value — appropriately 
 called a " Governor." Its purpose is to render 
 equal the height of flame of the several burners in 
 any house or establishment, and to keep them so, 
 notwithstanding any, and whatever alteration may 
 be made in the pressure at the works or elsewhere. 
 This instrument is perfected, and successfully ap- 
 plied, though it is not so generally in use as it 
 ought to be. By the use of this instrument a light 
 once set at the height desired will maintain that 
 height uniformly, and without the least variation 
 the whole evening; and continue to do so till 
 altered. 
 
 Without this instrument, it is necessary to pay 
 attention to the burning of gas lights, as their 
 heights are frequently affected by the most trifling 
 circumstance, such, for example, as their extinc- 
 tion at the hour of closing the shops, which makes 
 a sensible difference in the neighbourhood. 
 All these works have prodigiously increased in the quantity of gas made and sup- 
 plied. Since the account in the former edition of this work, large additional manufac- 
 tories have been erected by new companies, and great additions made by the old ones. 
 There are now in the metropolis alone 15 public gas companies, having amongst them 
 23 gas establishments. The quantity of gas manufactured by these 23 gas works, and 
 supplied to the public was during the past year three thousand one hundred millions 
 of cubic feet of gas ; and the coal used to produce this quantity of gas was at the least 
 400,000 tons ! 
 
 Baked clay retorts are very generally used in Scotland, and found to be most econo- 
 mical as regards wear and tear ; in London, however, they are mostly of cast iron. 
 
 The pressure upon the retorts is caused principally by the use of wet lime, used in 
 London, because the process is less expensive and less cumbersome than dry lime. 
 Wet lime cannot be used with clay retorts, owing to this excess of pressure. 
 
 Merit is due, for enlarging the capacities of double gas holders, to the late 
 Mr. Joshua Horton, of West Bromwich, near Birmingham : and to Mr. Stephen 
 Hutchison, engineer, of the New London Gas Works, Vauxhall, where they were 
 first successfully introduced, and manufactured by Mr. Horton. They have now 
 come very generally into use throughout the kingdom, and are manufactured by all 
 gasholder makers. 
 
 Separate gasholders are advisable and advantageous, but they are not generally 
 used, except in Glasgow, Manchester, Birmingham, Sheffield, and a few other places. 
 
 The annexed drawing represents Mr. Croll's vessels for the purification of gas from 
 ammonia, which is effected by means of dilute sulphuric acid applied between the con- 
 densers and the ordinary lime purifiers. The vessels are made of either wood or iron, 
 and lined with lead ; have a washplate similar to the wet lime purifiers. The radiat- 
 ing bottom formed of wooden bars, as shown in the drawing, is for the purpose of 
 supporting the washplate and distributing the gas. 
 
 Fig. 67. a, is the inlet pipe ; b, the outlet pipe; c, c, the tube with funnel for 
 introducing the sulphuric acid ; d, the first purifying vat ; e, the second do., both 
 lined with lead, and which are filled up to the dotted line with the dilute acid ; f,f, 
 the water supply-pipe ; g, g, the discharging cocks. 
 
 Fig. 68. represents a ground-plan of the vats, each 10 feet in diameter; A, the 
 bottom of the middle ; B, the inlet of the gas ; C, the outlet of do. 
 
 In commencing the process, these vessels are charged with water and sulphuric acid, 
 in the proportion of 7 pounds, or thereabouts, of the latter, to 100 gallons of the 
 former. As the acid is neutralized by the ammonia contained in the gas passing 
 through the vessels, the above proportion, as near as may be, is kept up by a continuous 
 dropping or running of acid, regulated according to the quantity of ammonia contained 
 
 r 2 
 
108 
 
 GAS-LIGHT. 
 
 in the gas, from a reservoir placed on the top of the saturator. This mode of supplying the 
 acid is continued until the specific gravity of the solution arrives at 1 170, or close to the 
 
 point of crystallization, after which the supply of acid is discontinued, and the liquor re- 
 tained in the vessel until neutral, when it is drawn off and evaporated, and yields a pure 
 sulphate of ammonia. 
 
 This process has been introduced at several of the provincial gas works, the three 
 stations of the Chartered, the Imperial, Phoenix, &c. &c. Mr. Croll is also now in 
 treaty with several other companies for its introduction. 
 
 The produce — sulphate of ammonia — from the process, by the gas companies using 
 it, now amounts to several tons per week — and it may be here mentioned, as one of the 
 advantages of science, that the ammonia so produced before the adoption of this process 
 passed along with the gas to the consumer, destroying rapidly the main pipes, fittings, 
 and metres, through which it was transmitted, as well as deteriorating the illuminating 
 power of the gas, and producing a choky effect when consumed in close apartments. It is 
 now employed as a manure, and found to be superior in its effects as a fertilizer, as well 
 as comparatively cheaper than any of the other artificial manures ; so that whether 
 Mr. C.'s invention be looked upon as effecting improvements in the manufacture of gas, 
 hitherto unknown, or as producing a valuable manure, the results are alike of the utmost 
 importance. 
 
 (When Mr. Croll's process is employed before the lime purifiers, dry lime can be 
 used without creating the nuisance hitherto complained of, and a much less quantity is 
 required for this purification. ) 
 
 Mr. Croll has recently patented another invention, connected also with the manufac- 
 ture of gas, which consists in the combination of clay and iron retorts, so that the heat 
 of the furnace first acts on the clay retorts and then passes to those of iron. 
 
 The annexed drawing is a transverse section : — 
 
 a is the fire-place. 
 
 b b are piers of fire bricks, placed at intervals to form nostrils or flues, and the fire 
 tile resting upon them in conjunction with the front and back wall, form the bed or 
 support of the clay retort 1, and the clay retort 2, is also supported by the front and 
 back brick work, and a lump, or fire brick, e, placed midway on the crown of the 
 retort 1. 
 
 f is a wall which separates the clay retorts 1 and 2, and the iron retorts 1° and 2° ; a 
 space being left between the top of the said wall f, and the under surface of the arch, to 
 allow the fire or heated air to pass freely from the clay to the iron retorts. , 
 
 g g is the bed, and h h is the flue under the iron retort 1°. The retort 2°, is supported 
 by the front wall and pieces or lumps. 
 
 j, placed at the back and crown of the retort 1°, in connection with the horizontal 
 flue, h is a vertical flue, forming a passage from thence into the shaft or chimney. 
 
 The heat passes from the furnace or fireplace a, through the spaces or nostrils formed 
 by the piers b b, and around the clay retorts 1 and 2, over the wall f, descends between 
 and around the iron retorts and along the flue h, and escapes by the vertical flue into 
 the chimney. The advantages of this mode of setting retorts are the small quantity of 
 
GAS-LIGHT. 
 
 109 
 
 brickwork necessary for the erections, the increased durability of the retorts, and the 
 economy in fuel. From adopting this mode of setting a brick lump, it has been found 
 that 12 tons of coke will carbonise 100 tons of coal. 
 
 L is the chimney stalk, and d is a damper or register plate for regulating the chimney 
 draught. 
 
 Before dismissing Mr. Croll's patent improvements, it is proper to state, that the sul- 
 phuric acid used for condensing the ammonia should be free from iron, otherwise the 
 sulphuretted hydrogen of the coal gas is apt to give rise to sulphuret of that metal which 
 will blacken the sulphate of ammonia and reduce its value in the market. An occur- 
 rence of this kind was recently brought professionally before me for investigation. The 
 sulphuric acid had been made from pyrites. 
 
110 
 
 GAS-LIGHT. 
 
 Copy of a paper laid before a Committee of the House of Commons, showing not 
 only the relative values of the Gases produced at the under-mentioned places, but 
 showing in like manner the relative economy of Gas, as produced at the different 
 places, over candles. By Joseph Hedley, Esq. 
 
 
 Illuminat- 
 
 The Jet of 
 
 
 
 
 
 
 
 
 
 
 
 
 
 Gas burnt. 
 
 Gas required 
 
 
 
 
 
 
 
 
 
 
 
 Names of the Places 
 
 ing power of 
 a single Jet 
 of Gas-flame 
 
 four inches ,to be equal to 
 high, con- 100 lbs. of 
 sumed Der mould 
 
 Selling 
 price of Gas 
 
 Cost of Gas 
 
 equal in il- 
 luminatinir 
 
 Average 
 discount 
 allowed 
 
 Net cost 
 of Gas 
 
 Specific 
 
 
 four inches 
 
 hour and 
 
 Candles 6 to 
 
 per meter 
 per J 000 
 cubic feet. 
 
 DO 
 
 
 to ' 
 
 off the 
 
 
 ual to 
 
 gravity of 
 
 were made. 
 
 high, taken 
 by a com- 
 parison of 
 Shadows. 
 
 was equal to 
 the Candles 
 
 the lb.', 9 
 inches long 
 
 100 lbs. of 
 candles, t 
 
 charge for 
 Gas. 
 
 100 lbs. of 
 Candles. 
 
 the Gas. 
 
 
 in the last 
 column. 
 
 each.* 
 
 
 
 
 
 
 
 
 
 
 
 Equal to 
 Candles. 
 
 Cubic Feet. 
 
 Cubic Feet. 
 
 
 d. 
 
 L. 
 
 1. 
 
 d. 
 
 er ,en . 
 
 L 
 
 ». 
 
 d. 
 
 
 Birrnin^hcirn \ ^ 
 BirminghcitYi cincl C 
 Staffordshire ; f 
 
 
 
 
 
 
 2-572 
 
 1-22 
 
 2704 
 
 10 
 
 0 
 
 1 
 
 7 
 
 0 
 
 9 
 
 1 
 
 4 
 
 7 
 
 •541 
 
 two CornpciniGS J 
 
 
 
 
 
 
 
 
 
 
 
 
 
 •534 
 
 Stockport 
 
 3-254 
 
 •85 
 
 1489 
 
 10 
 
 0 
 
 0 
 
 14 
 
 11 
 
 m 
 
 0 
 
 13 
 
 0 
 
 Manchester - 
 
 3060 
 
 •825 
 
 1536 
 
 8 
 
 0 
 
 0 
 
 12 
 
 ?. 
 
 «i 
 
 0 
 
 30 
 
 10 
 
 
 Liverpool Old ~t 
 CompanyJ - j 
 
 2-369 
 
 M 
 
 2646 
 
 10 
 
 0 
 
 1 
 
 6 
 
 5 
 
 H 
 
 I 
 
 4 
 
 9 
 
 •4 
 
 Liverpool New) 
 Gas Company $ 
 Bradford 
 
 4-408 
 
 •9 
 
 1164 
 
 10 
 
 0 
 
 0 
 
 11 
 
 8 
 
 6i 
 
 0 
 
 9 
 
 10 
 
 •580 
 
 2-190 
 
 1-2 
 
 3123 
 
 9 
 
 0 
 
 
 8 
 
 1 
 
 12* 
 
 1 
 
 4 
 
 6 
 
 •420 
 
 Leeds - 
 
 2-970 
 
 •855 
 
 1644 
 
 8 
 
 0 
 
 0 
 
 13 
 
 2 
 
 6* 
 
 0 
 
 12 
 
 4 
 
 •530 
 
 Sheffield 
 
 2-434 
 
 1-04 
 
 2440 
 
 8 
 
 0 
 
 0 
 
 19 
 
 6 
 
 
 0 
 
 18 
 
 3 
 
 •466 
 
 Leicester 
 
 2435 
 
 11 
 
 2575 
 
 7 
 
 6 
 
 0 
 
 19 
 
 3 
 
 15 
 
 0 
 
 16 
 
 5 
 
 •528 
 
 Nottingham - 
 
 1-G45 
 
 1-3 
 
 4200 
 
 9 
 
 0 
 
 1 
 
 17 
 
 9 
 
 15 
 
 1 
 
 11 
 
 3 
 
 •424 
 
 Derby - 
 
 1-937 
 
 1-2 
 
 3521 
 
 10 
 
 0 
 
 1 
 
 15 
 
 4 
 
 15 
 
 1 
 
 10 
 
 0 
 
 •448 
 
 Preston - 
 
 2-136 
 
 1-15 
 
 3069 
 
 10 
 
 0 
 
 1 
 
 10 
 
 8 
 
 15 
 
 none 
 
 1 
 
 6 
 
 2 
 
 •419 
 
 London 
 
 2-083 
 
 1-13 
 
 3092 
 
 10 
 
 0 
 
 1 
 
 10 
 
 11 
 
 allowed. 
 
 1 
 
 10 
 
 11 
 
 •412 
 
 * 100 lbs. of candles are estimated to burn 5700 hours. f The candles cost 31. 2s. Gd. 
 J The Liverpool Old Company have since resorted to the use of Cannel coal, and consequently very 
 nearly assimilate to the Liverpool New Company in illuminating power. 
 
 Memorandum. — It will not-fail to be observed that in deducing the comparative value 
 between candles and gas by these experiments, the single jet (and in every instance, 
 of course, it was the same), has been the medium. This, however, though decidedly 
 the most correct way of making the comparative estimate of the illuminating power 
 of the several gases, is highly disadvantageous in the economical comparison, inasmuch 
 as gas burnt in a properly regulated argand burner, with its proper sized glass, air 
 aperture, and sufficient number of holes, gives an advantage in favour of gas consumed 
 in an argand, over a jet burner, of from 30 to 40 per cent. At the same time it 
 must not be overlooked that in many situations where great light is not required, it 
 will be found far more economical to adopt the use of single jets, which by means of 
 swing brackets and light elegant shades, become splendid substitutes for candles, in 
 banking establishments, offices, libraries, &c. &c. 
 
 Note. — In Glasgow, Edinburgh, Dundee, Perth, and the Scotch towns, generally, 
 the Parrot or Scotch Cannel coal is used ; in illuminating power and specific gravity 
 the gas produced is equal to that from the best description of Cannel coal in England. 
 The price per 1000 cubic feet ranges about 9s., with from 5 to SO per cent, off for 
 discounts, leaving the nett price about 9s. to be equal in the above table to 100 lbs. 
 of candles. 
 
 Epitome of Experiments made in Gas produced from different qualities of Coal, and 
 consumed in different kinds of Burners, tried at the Sheffield Gas Light Company's 
 Works, and laid before a Committee of the House of Commons. By Joseph 
 Hedley, Esq. 
 
 Date 
 1835. 
 
 Description of 
 Burner. 
 
 Species of 
 Coal. 
 
 Specific 
 Gravity of 
 Gas. 
 
 Distance 
 of Candle 
 
 from 
 Shadow. 
 
 Gas 
 con- 
 sumed 
 
 per 
 Hour. 
 
 Height 
 of Gas- 
 flame. 
 
 Equal to 
 Mould 
 Tallow 
 Candles, 6 to 
 the pound, 9 
 inches long 
 each. 
 
 Gas equal 
 to 100 lbs. 
 of Mould 
 Candles. 
 
 Cost of Gas 
 at Ss. 
 per 1000 
 cubic feet. 
 
 Cost of 
 100 lbs. of 
 Mould 
 Candles 
 at 7s. 6d. 
 per dozen 
 lbs. 
 
 Ma,. 
 
 9 
 9 
 8 
 
 9 
 9 
 
 Single Jet 
 Ditto 
 Ditto 
 
 ("Argand \ 
 t 14 holes J 
 
 Ditto 
 
 Ditto 
 
 Deep Pit 
 
 Mortormley 
 
 Cannel 
 
 Deep Pit 
 
 Mortormley 
 Cannel 
 
 •410 
 
 •450 
 •660 
 
 •410 
 
 •450 
 •660 
 
 Inches. 
 
 75 
 74 
 
 614 
 
 34 
 
 33 
 29 
 
 Cubic 
 Feet. 
 P 
 
 •95 
 •7 
 
 3 3 
 
 31 
 
 2-6 
 
 Inches. 
 4 
 4 
 4 
 
 H 
 
 3* 
 
 Candles. 
 2-36 
 
 2- 434 
 
 3- 54 
 
 11- 53 
 
 12- 24 
 
 1585 
 
 Cubic Feet. 
 2415 
 2224 
 
 1127 
 1631 
 
 1443 
 
 935 
 
 L. s. d. 
 0 19 3§1 
 0 17 9$ 
 0 9 0 
 
 0 13 0> 
 
 0 11 6h 
 
 0 7 52, 
 
 ► 
 
 L. t. d. 
 
 3 2 6 
 
 I 
 
GAS-LIGHT. 
 
 Ill 
 
 Copy of Experiments made at the Alliance Gas Company's Works in Dublin, during 
 the past year 1837. By Joseph Hedley, Esq. 
 
 Results of experiments on the qualities of various coals for the production of gas ; 
 its value in illuminating power ; produce of coke, and quality ; and other particulars 
 important in gas-making : — 
 
 1st Experiment, Saturday, May 21th, 1837. — Deane coal (Cumberland), 2 cwt. of 
 1 12 lbs. each (or 224 lbs. ) produced 970 cubic feet of gas ; 4 bushels of coke of middling 
 quality ; specific gravity of the gas, 475. Consumed in a single-jet burner, flame 4 
 inches high, 1 T 4 5 cubic feet per hour ; distance from shadow 76 inches or 2-3 mould 
 candles. Average quantity of gas made from the charge (6 hours) 4-33 cubic feet per 
 lb., or 9700 cubic feet per ton of 20 cwt. Increase of coke over coal in measure, not 
 quite 30 per cent. Loss in weight between coal, coke, and breize 56 lbs., converted 
 into gas, tar, ammonia, &c. 
 
 2nd Experiment, May 28th. — Carlisle coal (Blenkinsopp). 224 lbs. produced 1010 
 cubic feet of gas, 4 bushels of coke of good quality though small ; increase of coke 
 over coal in measure not quite 30 per cent. Loss in weight, same as foregoing experi- 
 ment. Average quantity of gas made from the charge (6 hours) 4-5 cubic feet per lb. 
 or 10,080 per ton. 
 
 Illuminating Power of the Gas. 
 
 
 Consumed 
 per hour, 
 single jet. 
 
 Distance 
 from candle. 
 
 Equal to 
 candles. 
 
 Specific 
 gravity. 
 
 At the end of the 1 st hour 
 Ditto ditto with 20-hole 1 
 
 argand burner - - J 
 When charge nearly off* 
 When charge quite off, with 20- 1 
 
 hole argand burner - J 
 
 Feet. 
 »* 
 5 
 
 9 
 
 Inches. 
 70 
 
 25 
 
 85 
 
 100 
 
 2'72 
 21-33 
 1-84 
 not 1 
 
 •475 
 •475 
 •442 
 •266 
 
 Srd Experiment, May 29th. — Carlisle coal (Blenkinsopp). 1 12 lbs. produced 556 
 cubic feet of gas. Other products, loss of weight, &c, same proportion as foregoing 
 experiment. Average quantity of gas made from the charge (6 hours) 4*96 cubic feet 
 per lb., or 11,120 per ton. 
 
 In this experiment the quantity of gas generated every hour was ascertained ; the 
 illuminating power, the specific gravity, and the quantity of gas consumed by the single 
 jet with a flame 4 inches high, Avas tried at the end of each hour, with the respective 
 gases generated at each hour ; and the following is a table of results. 
 
 RESULTS. 
 
 Hour. 
 
 Gas produced. 
 
 Consumed 
 per hour 
 per single jet, 
 4 inches high. 
 
 Specific gravity. 
 
 Distance of 
 candle from 
 shadow. 
 
 Illuminating 
 power equal to 
 mould candles. 
 
 1st. 
 
 Cubic Feet. 
 150 | 
 
 Cubic Feet. 
 ll|-10ths. \ 
 or 1-15 J 
 
 •534 
 
 Inches. 
 70 
 
 2-72 
 
 2nd. 
 
 Srd. 
 
 4th 
 
 5th. 
 
 6th. 
 
 120 
 95 
 95 
 80 
 16 
 
 11 
 
 12 
 15 
 17 
 
 29 
 
 •495 
 •344 
 •311 
 •270 
 •200 
 
 75 
 75 
 80 
 85 
 100 
 
 2-36 
 2-36 
 2-08 
 1-81 
 not one 
 
 Total 
 
 556 
 
 
 
 
 
 Average of the above gas, 6-hour charge. 
 92§ 16-10ths. nearly -359 81 2 OS 
 
 Average of the above gas at 4-hour charge. 
 115 12^-10ths. -421 75 2*36 
 
 Production of gas in 6 hours 556 feet, or at the rate of 11,120 cubic feet per ton. 
 Ditto in 4 hours 460 feet, or at the rate of 9,200 ditto. 
 
112 
 
 GAS-LIGHT. 
 
 12-10ths. 
 
 The relative value of these productions of gas is as follows, viz. : — 
 
 11,120 at 1 6- lOths per hour nearly, (or 1*5916 accurately) and equal to 22*03 candles; 
 the 11,120 feet would be equal to and last as long as 1597 candles, or 266£ lbs. of 
 candles. 
 
 9200 at 12»-10ths. per hour, (or 1*2375 accurately) and equal to 2*36 candles; the 
 9200 feet would be equal to 1 949 candles, or 324| lbs. candles. 
 
 Now 266^ lbs. of mould candles, at 7s. 6d. per dozen lbs., will cost Si. 6s. 4}/i., whilst 
 324|lbs. of do. do. at 7s. 6d. per do. do. 10Z. 3s. 
 
 Showing the value of 4-hour charges over 6-hour charges ; and of 9200 cubic feet 
 over 11,120 cubic feet. 
 
 Note. — 9500 cubic feet of Wigan cannel coal gas are equal in illuminating power to 859 1-Gth lbs. of 
 candles, which at 7s. 6d. per dozen lbs. will cost 25/. 10s. 5irf. It is also found that any burner with 
 superior gas, will consume only about half the quantity it would do with common gas. 
 
 4th Experiment, May 30th. — Cannel and Cardiff coal mixed | and together 112 lbs., 
 produced 460 feet of gas, 2 bushels of coke of good quality ; increase of coke over coal 
 in measure about 30 per cent. ; loss in weight 41 lbs. ; coke weighed 71 lbs., no breize. 
 Average quantity of gas made from the charge, (4 hours) 4*1 cubic feet per lb., or 
 9 *200, per ton. 
 
 Illuminating Power. — At end of first hour, 
 
 Candles. Cubic Feet. 
 
 Distance of candle from") ^ q ^ ^.49 f Consumed per hour, single 
 
 shadow J ' \ jet, 4 inches high - 
 
 At end of 2nd hour, do. 70 or 2*72 Do. do. do. " lH-10ths. 
 
 At end of 3d hour. This gas very indifferent. 
 
 Average of the three - 70 or 2*72 Do. do. do. lH-10ths 
 
 Specific gravity 3*44; 5 feet per hour, with a 20-hole argand burner, equal to 14*66 
 candles. 
 
 5th Experiment, May 31st. — Carlisle coal, 112 lbs. produced 410 feet of gas ; other 
 products, same as in former experiments with this coal, but heat very low. 
 
 Illuminating Power and Produce of Gas. 
 
 Average of this gas : specific gravity, 540 ; 
 distance of candle from shadow, 55 inches, 
 or 4*4 candles consumedjDer single jet, 9- 
 lOths of a cubic foot per hour. 20-hole 
 argand burner, 4 feet per hour, equal to 
 21 *33 candles. 
 
 It is possible, from the superior quality of this gas, that a little of the cannel gas 
 made for a particular purpose may have got intermixed with it in the experimental 
 gasholder and apparatus. 
 
 Various other experiments were tried on different qualities of coal, and mixtures 
 of ditto, too tedious to insert here, though extremely valuable, and all tending to show 
 the superior value of gas produced at short over long charges ; and also showing the 
 importance and value of coal producing gas of the highest illuminating power ; among 
 which the cannel coal produced in Lancashire, Yorkshire, and some other counties of 
 England and Wales, and the Parrot or splent coal of Scotland, stand pre-eminent. 
 
 Note — In all the foregoing experiments the same single-jet burner was used ; its flame in all in- 
 stances exactly 4 inches high. 
 
 The coal when drawn from the retort was slaked with water, and after allowing some short time for 
 drying, was weighed. 
 
 A Table of the Number of Hours Gas is burnt in each Month, Quarter, and Year. 
 
 410 feet 
 
 ' 1 st hour 1 20 cubic feet. 
 2nd 100 
 3d 90 
 4th 100 
 
 Time of Burning. 
 
 July. 
 
 Aug. 
 
 Sep. 
 
 Oct. 
 
 Nov. 
 
 Dec. 
 
 Jan. 
 
 Feb. 
 
 Mar. 
 
 Apl. 
 
 May- 
 
 June 
 
 Mid.iMic. 
 
 Xms. 
 
 Lady 
 day 
 
 Totl 
 of 
 
 
 
 
 
 
 
 
 
 
 
 
 
 quar. 
 
 quar. 
 
 quar. 
 
 quar. 
 
 Vear 
 
 
 o'clock. 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 From Dusk to 6 
 
 
 
 2 
 
 31 
 
 62 
 
 80 
 
 65 
 
 33 
 
 4 
 
 
 
 
 
 2 
 
 173 
 
 102 
 188 
 
 277 
 493 
 
 
 — 7 
 
 
 14 
 
 22 
 
 62 
 
 92 
 
 111 
 
 96 
 
 61 
 
 31 
 
 4 
 
 
 
 4 
 
 36 
 
 265 
 
 1 
 
 _ 8 
 
 
 40 
 
 52 
 
 93 
 
 122 
 
 142 
 
 127 
 
 89 
 
 62 
 
 28 
 
 4 
 
 
 32 
 
 92 
 
 357 
 
 278 
 368 
 
 759 
 
 -a 
 
 — 9 
 
 13 
 
 71 
 
 82 
 
 124 
 
 152 
 
 173 
 
 158 
 
 117 
 
 93 
 
 58 
 
 29 
 
 8 
 
 95 
 
 166 
 
 449 
 
 1078 
 
 & 
 
 — 10 
 
 44 
 
 102 
 
 112 
 
 155 
 
 182 
 
 204 
 
 189 
 
 145 
 
 124 
 
 88 
 
 60 
 
 38 
 
 186 
 
 258 
 
 541 
 
 458 
 
 1443 
 
 
 — 11 
 
 75 
 
 133 
 
 142 
 
 186 
 
 212 
 
 235 
 
 2'2() 
 
 173 
 
 155 
 
 118 
 
 91 
 
 68 
 
 277 
 
 350 
 
 633 
 
 548! 1808 
 
 °£ 
 
 CO > 
 
 — 12 
 
 106 
 
 164 
 
 172 
 
 217 
 
 242 
 
 266 
 
 251 
 
 201 
 
 186 
 
 148 
 
 122 
 
 98 
 
 368 
 
 442 
 
 725 
 
 6382173 
 
 c? £ 
 
 All night 
 
 217 
 
 307 
 
 345 
 
 421 
 
 473 
 
 527 
 
 512 
 
 411 
 
 382 
 
 295 
 
 242 
 
 195 
 
 732 
 
 869 
 
 1421 
 
 13054327 
 
 ■§2 
 
 Morning from 4 
 
 
 16 
 
 48 
 
 80 
 
 110 
 
 137 
 
 137 
 
 98 
 
 71 
 
 28 
 
 2 
 
 
 30 
 
 64 
 
 327 
 
 306 727 
 
 £ 5 
 
 — 5 
 
 
 
 18 
 
 49 
 
 80 
 
 10G 
 
 106 
 
 70 
 
 40 
 
 3 
 
 
 
 3 
 
 18 
 
 235 
 
 216 
 
 472 
 269 
 
 
 — 6 
 
 
 
 
 18 
 
 50 
 
 75 
 
 75 
 
 42 
 
 9 
 
 
 
 
 
 
 143 
 
 126 
 
 68 
 
 u 
 
 0 
 
 — 7 
 
 
 
 
 
 20 
 
 44 
 
 M 
 
 14 
 
 
 
 
 
 
 
 64 
 
 122 
 
 
GAS-LIGHT. 
 
 113 
 
 I 
 
 If 
 
 if 
 
 pllllllllllllllilllllllli 
 
 lllllllllsllllgslllllllll 
 
 imrnmrnmimm 
 
 f 
 
 lisllslllllgillllllllilli 
 
 iipiiiiliiiiliiiiiiiiiiii 
 
 iiiiiiiiippipiiiiiiiiiiii 
 
 IIIIl?III ? lfsl^|IiliiIIi 
 
 lgillllllllllllplllllllll 
 
 Ilsl5Slllll2 ? Ilf||ll|lsl| 
 
 lllllpllllllllsllflllllsi 
 
 llllllllllllllllillllllll 
 
 H H11§|1I||1|1III11I|II||I1 
 
 •fftl-ff 
 
 .Ji. Ji.fi. Ji Si. Si. 
 
 llllllllllllllllillllllll 
 
 1 
 
 I! 
 
 PI 
 
 Ji* 
 
 II 
 
 si 
 
 in 
 in 
 
 s a s 
 
 li 
 
 Mil i 
 Jll 
 
 I i s 
 
 Is Hit 1 
 
 mi 
 Hi 
 
 lir 
 
 ilfl 
 
 aft 
 
114 
 
 GAS-LIGHT. 
 
 Copy of a Paper submitted to a Committee of the House of Commons in the Session of 1837, 
 
 of England ; and procured by actual Survey and 
 
 
 
 
 No. of 
 
 
 Ma- 
 
 Quan- 
 
 Public 
 
 Selling 
 
 terial 
 
 tity 
 
 or 
 Street 
 
 Price of 
 
 usual to 
 
 used 
 
 Coke. 
 
 heat 
 
 per Ton 
 
 Lamps 
 
 
 Retorts. 
 
 of Coal. 
 
 sup- 
 
 
 
 
 plied. 
 
 2s.'ld. per 
 
 Slack. 
 
 About 
 
 490 
 
 quarter 
 
 
 
 
 delivered, 
 
 
 of slack, 
 
 
 or about 
 
 
 at 6s. 
 
 
 3d. per 
 
 
 per ton, 
 
 
 bushel. 
 
 
 25 per 
 
 
 
 
 cent. 
 
 
 2s. lOd. 
 
 Slack 
 
 5 cwt. 
 
 1..500 
 
 per sack 
 
 and 
 
 of slack, 
 
 
 of 8 
 
 Tar. 
 
 at 4s. 
 
 
 bushels. 
 
 
 25 per 
 
 
 
 
 cent. 
 
 
 10*. 
 
 Coke. 
 
 No 
 
 220 
 
 per ton. 
 
 
 account 
 
 
 
 kept. 
 
 
 6t. 8d. 
 
 Coal, 
 
 Ditto. 
 
 230 
 
 per ton. 
 
 coke, 
 
 
 
 
 and tar. 
 
 
 
 Ditto. 
 
 Coke. 
 
 4, 2-3ds 
 
 2,375 
 
 
 
 cwt. 
 
 
 8*. id. 
 
 Slack. 
 
 6£ cwt. 
 
 1,700 
 
 per ton of 
 
 7*. 3d. 
 
 30 
 
 1121b. 
 
 per ton. 
 
 
 
 per cwt. 
 
 
 
 
 Name of the 
 Place where 
 Gas Works 
 are situated. 
 
 Birmingham 
 Gas Com- 
 pany. 
 
 Jirmingham 
 and Staf- 
 fordshire. 
 
 Stockport 
 
 10*. per 1000 cub. feet. 
 Discounts, 
 in;, to 30/. A 2\ «3 
 30/. to 50/. * 5 £ 
 50/. to 75/. S 7\ 1 
 75/. to 100/. «■ 10 55 
 100/. & upwards 15 ^ 
 10.?. per 1000 cub. feet. 
 Discounts as above. 
 
 10*. per 1000 cub. feet. 
 Discounts. 
 50/. 75/. 5 
 75/.^ £100/. 7\ J 
 100/. °f J 25/. 10 £ 
 125/. Z $ 150/. 124, " 
 <; 150/. c "175/. 15 Jj 
 175/. " £200/. 174 ^ 
 200/. & upwards 20 
 0*. per 1 000 cub. feet. 
 Discounts same as Mac- 
 clesfield. Macclesfield 
 discounts taken from 
 Stockport card. 
 
 10s. perm. cub. ft. 1834. 
 9*. and 8*. — 1837. 
 Discounts 
 
 50/. 
 
 ioo/. 
 
 150/. 
 20"/. 
 225/. 
 250/. 
 301 >l. 
 
 Liverpool Old 
 Company, 
 1834. 
 
 Ditto ditto - 
 Liverpool 
 New Gas and 
 
 Coke, 1835. 
 Bradford, 
 
 1834. 
 
 Leeds, 1834 
 
 Sheffield, 
 1835. 
 
 Leicester, 
 1837. 
 
 Derby, 1S34. 
 
 Nottingham, 
 1831. 
 
 !London,1834 
 
 Price of Coal 
 
 and 
 Description ; 
 delivered per 
 
 Ton. 
 
 Lump coal 
 from West 
 Bromwich 
 pits risen 
 much of late 
 1837,li*.10c/. 
 
 From West 
 Bromwich 
 pits, 1837, 
 9s. 3d. 
 
 Common, 8s. 
 average 1834. 
 
 Coal 10s. 6d. 
 cannel I9s.6d. 
 about half and 
 
 half used. 
 Average 15*. 
 1834. 
 15*. 2d. 
 average. 
 Oldham T 
 Water i c 
 
 gate 
 
 7 h S V^igan -j o 
 10 u Mixed, 1831. 
 124 55! 
 15' H 
 17* 
 
 Cu.ft. 
 6,500 
 
 Coke 
 made 
 from a 
 Ton of 
 Coal. 
 
 32 
 bushels. 
 
 24 bush, 
 but larger 
 measure 
 than Bir- 
 mingham 
 12 cwt. 
 
 100/ 
 150/ 
 20O/. 
 225/. 
 250/. 
 300/. 
 400/. 
 
 400/. & upwards 20 
 
 '0*. per 1000 cub. feet. 7«- 3d. per ton 8,200 11£ cwt. 8*. 4d. Slack. cwt. 1»700 Batswings 
 Discounts. of 112 lbs. per per ton of 7*. 3d. 30 1 jet, 
 
 10/. & under 30/. 24. cwt.Ormskirk 1121b. per ton. 2- 
 
 30/. to 100/. 5 u | or Wigan per cwt. 3 . 
 
 100/. to 200/. 7iS3 1 slack. 4- 
 
 300/. & upwards 10 
 
 In 1835 this Company resorted to the use of cannel coal similar to the Liverpool New Gas and Coke Company, producing nearly 
 
 Description 
 Size or Sort. 
 
 Batswings 
 460 
 50 
 
 Batswings. 
 
 Single jets 
 and flat 
 flames, 
 about half 
 and half. 
 
 Price 
 paid per 
 Annum 
 for 
 
 Ditto, 
 
 L. *. 
 
 1 10 
 
 2 0 
 
 2 10 0 
 
 1834 
 2 0 0 
 
 1837. 
 
 Who lights, 
 cleans, puts out 
 and repairs. 
 
 Company, and 
 provides posts, 
 services, &c. 
 
 Company. 
 
 Comrs. provide 
 lamps and posts. 
 Company's 
 service light, 
 repair, clean, 
 and extinguish, 
 Commissioners 
 of police. 
 
 Company 
 light, clean, put 
 
 2 13 Ojout, and repair. 
 
 3 2 9 
 3 13 11 
 
 10*. per 1000 cub. feet. 
 Discounts same as Li- 
 verpool Old Company. 
 9s. per 1000 cub. feet 
 to large consumers. 
 Discounts 
 20/. to 30/. 5 
 30/. to 40/. 74 c 
 40/. to 60/. 10 £ 
 60/. to 80/. 124 Z 
 80/. to 100/. 15 S 
 100/. & upwards 20. 
 
 Small consumers, 
 10*. per 1000 cub. feet, 
 and 5 per cent, off 
 from 10/. to. 20/. 
 
 Discounts. 
 
 fper cent, on I 
 half-yearly ^ 
 payments I 
 
 8*. per 1000 cubic feet. 
 Discounts same asLeeds 
 
 7s. 6d. per 1000 cub. ft 
 
 Discounts on half-ye.irl; 
 rental not exceeding 
 10/., 5 per cent. 
 10/. M20/. 74 
 £ 20/. §| 30/. 10" 
 § 30/. f | 40/. 124. g 
 
 40/. 
 
 50/. 
 
 50/. 15 
 60/ 20 K 
 
 60/.& upwards 2. 
 10«. per 1000 cub. feet. 
 Discounts. 
 5 to 35 per cent. 
 3*. per 1000 cubic feet 
 Discounts as above. 
 
 10*. per 1000 cub. feet 
 
 18*. all cannej 
 Wigan. 
 
 is.6d. per ton. 
 3 sorts used 
 
 average. 
 Slack 5*. 6d. 
 Low Moor 
 
 8*. lOd. 
 Catherine 
 slack 8*. 
 
 9,500 
 
 is. per ton 
 average. 
 2-3ds common 
 7s. 
 
 l-3d cannel, 
 10*. 
 
 7s. 9d. per ton 
 
 average. 
 3 sorts used, 
 1, 2-10ths 
 cannel, at 16*. 
 8,2-10ths 
 deep pit, 7s. 
 l-10th 
 silk stone, 10*. 
 13*. 6d. 
 average. 
 Derbyshire 
 soft coal. 
 
 Same coal 
 used as at 
 Leicester. 
 Ditto. 
 
 10 cwt. 
 if saleabl 
 coke. 
 
 4 quarters 
 
 7*. U. 
 per ton. 
 
 12*. 
 per ton. 
 
 Coke 
 and 
 
 slack. 
 
 Coke. 
 
 5i cwt. 
 8$ cwt. 
 
 Only a 
 few. 
 
 220 
 
 Argands. 
 Batswings. 
 
 7s. 6d. 
 per ton. 
 
 Ditto. 
 
 5J cwt. 
 
 517 
 
 Ditto. 
 
 10*. 
 per ton. 
 
 Ditto. 
 
 3.^owt. 
 
 600 
 
 Ditto. 
 
 10*. 8d.' 
 or 2s. 8d. 
 per qr. 
 
 Coke, 
 tar, &c. 
 
 About 
 l-3d of 
 coke. 
 
 414 
 
 Ditto. 
 
 Ditto. 
 
 Coke. 
 
 Ditto. 
 
 219 
 
 Ditto. 
 
 Ditto. 
 
 Ditto. 
 
 Ditto. 
 
 300 
 
 Ditto. 
 
 12*. per 
 chaldron 
 
 Ditto. 
 
 13 bush. 
 
 26,280 
 
 Ditto. 
 
 Ditto. 
 
 Ditto. 
 
 Ditto. 
 
 30,400 
 
 Ditto. 
 
 4 0 0 Commissioners. 
 
 Company light, 
 repair, &c. 
 
 Commissioners; 
 except extin- 
 guishing, for 
 which Company 
 pay 3*. lOd. per 
 lamp. 
 
 Company 
 provide lamps, 
 clean, repair, 
 put out, &c. 
 
 Company light 
 put out, and 
 clean. 
 
 Commissioners 
 light, put out, 
 &c. 
 
 Commissioners 
 light, clean, 
 repair, &c. 
 Company light, 
 clean, put out, 
 but not repair. 
 
GAS-LIGHT. 
 
 115 
 
 being a Synopsis of the Proceedings of the under-mentioned principal Gas- Light Establishments 
 Experiments between the years 1834 and 1837. By Joseph Hedley, Esq. 
 
 No. of Hours, 
 or Time burnt 
 iu the Year. 
 
 Gas consumed in each 
 Lamp per Hour. 
 
 Rate per 1000 
 Cubic Feet received 
 for Ditto. 
 
 Amount deducted tor 
 cleaning, lighting, ex- 
 tinguishing, providing 
 Lamp Posts, &c. 
 
 Per Centage of 
 Loss of Gas made. 
 
 Greatest 
 Quantity of 
 
 Gas 
 delivered in 
 3ne Night. 
 
 Duration 
 of 
 
 Charges. 
 
 Method 
 of Purifi- 
 cation. 
 
 Number of 
 Gas 
 Holders. 
 
 Specific Gravity of 
 the Gas. 
 
 Distance of Candle 
 from Shadow. 
 
 Gas equal to Candles. 
 Gas burnt in a single 
 Jet Four Inches hiyh. 
 
 | Gas consumed per 
 1 Hour with a Four- 
 1 Inch Flame. 
 
 Gas Flame reduced to 
 Candle burnt per 
 Hour 
 
 Height ot Gas !■ lame 
 equal to Light from 
 Candle. 
 
 226 nights, or 
 2938 hours, 9 
 months, omit- 
 ting 5 nights 
 for moons. 
 
 5 feet 
 per 
 
 «. d. 
 30 10 
 40 18 
 
 4. d. 
 18 0 
 
 Receives nett 
 about 6s. 8d. per 
 1000 cubic feet. 
 
 Cubic Feet. 
 48 millions 
 in the year. 
 
 6 hours. 
 
 Dry lime. 
 
 4, and 2 in 
 the town, 
 and large 
 
 • new gas 
 station. 
 
 •453 
 
 Inch. 
 72 
 
 Candles 
 1,929 
 
 Cu.ft. 
 I'Wl 
 
 Cu.ft. 
 •8 
 
 Inch. 
 
 234 nights, or 
 3042 hours. 
 
 Ditto. 
 
 1 3£ 
 
 18 0 
 
 Receives nett 
 about 5s. 6d. per 
 1000 cubic feet. 
 
 85 millions 
 in the year. 
 
 Ditto. 
 
 Ditto. 
 
 6, and 6 in 
 the town 7 
 miles off. 
 
 •455 
 
 72 
 
 1,929 
 
 122 
 
 •8 
 
 
 8 months, 
 omitting 5 
 nights for 
 moons. 
 
 per 
 hour. 
 
 
 
 Could not say. 
 
 80,000. 
 Total for 
 year about 
 15 millions. 
 
 8 hours. 
 
 Ditto. 
 
 3 gas 
 holders. 
 
 Not 
 taken 
 
 70 
 
 204 
 
 Not 
 taken 
 
 •8 
 
 23 1 
 
 8 months. 4 
 nights omit- 
 ted for moons. 
 237 nights - 
 2800 hours. 
 
 Ditto. 
 
 2 6 
 
 12 6 
 
 Ditto. 
 
 65,000. 
 Total for 
 year about 
 12 millions. 
 
 Ditto. 
 
 Ditto. 
 
 4 gas 
 holders. 
 
 •539 
 
 64 
 
 2,441 
 
 •85 
 
 •55 
 
 n 
 
 3390 hours. 
 
 1 foot, 
 
 2 feet, 
 per 
 
 hour. 
 
 6 6 
 5 6 
 
 nothing 
 
 About 15 to 17 h 
 per cent, receive 
 about 7s. id. per 
 1000 cubic feet, 
 public and 
 private. 
 Nearly all by 
 
 500,000. 
 Total for 
 year 100 
 millions. 
 
 6 hours. 
 
 Wet lime. 
 
 10 gas 
 lolders, and 
 2 in the 
 town. 
 
 •534 
 
 66 
 
 2,295 
 
 •825 
 
 •475 
 
 22 
 
 3600 hours. 
 
 5 feet 
 per 
 hour. 
 
 4 4 
 
 12 0 
 
 Could not learn 
 in the absence of 
 the manager 
 
 360,000. 
 Total for 
 year 72 
 millions. 
 
 8 hours, 
 large 
 
 holding 
 6 cwt. 
 each. 
 
 Wet and 
 dry lime, 
 prin- 
 cipally 
 dry. 
 
 8 gas 
 holders in 
 all, 4 in the 
 town, 1000 
 yards off the 
 works. 
 
 •462 
 
 75 
 
 1,777 
 
 VI 
 
 •75 
 
 21 
 
 similar results, which see. 
 
 
 
 
 
 
 
 
 
 
 
 
 
 3000 hours. 
 
 8 months, 
 
 omitting 7 
 nights. 2600 
 
 hours to 4 
 o'clock in the 
 
 morning. 
 
 5h feet 
 
 per 
 hour 
 5 feet 
 per 
 hour. 
 
 5 6 
 3 1 
 
 nothing 
 12 6 
 
 Nearly all by 
 
 Receive 8*. per 
 1000 cubic feet, 
 less 5J per cent. 
 
 Not suffi- 
 ciently long 
 at work. 
 42,500. 
 Total for 
 
 year 
 8,619,000. 
 
 4 hours. 
 8 hours. 
 
 Wet lime. 
 Dry lime. 
 
 2 large 
 gas holders. 
 
 4 gas 
 holders. 
 
 •580 
 •420 
 
 55 
 78 
 
 3,306 
 1,643 
 
 •9 
 •12 
 
 •45 
 •9 
 
 2 
 3 
 
 2330 hours. 
 2200 hours. 
 
 4 feet 
 per 
 hour. 
 
 Ditto. 
 
 5 2 
 3 2J 
 
 
 Receive for public 
 and private (is- 8d. 
 per 1000 cubic 
 feet. Public 5s., 
 private 7s.; meters 
 used 5 to 1 for 
 private rental. 
 Receive for public 
 and private lights 
 5«. per 1000 cubic 
 feet. Public 
 34. 2hd., private 
 54. §id. Few 
 meters used. 
 
 176,000. 
 Total for 
 year 3 1 
 millions. 
 
 220,000. 
 
 Total for 
 year 40 
 millions. 
 
 6 hours. 
 Ditto. 
 
 Ditto. 
 Ditto. 
 
 5 gas 
 holders. 
 
 4 gas 
 holders, 
 and 2 more 
 erecting. 
 
 "530 
 •466 
 
 67 
 74 
 
 2,228 
 1,826 
 
 •85 
 P04 
 
 •51 
 •735 
 
 2 
 
 From August 
 14th to 
 
 September 
 1st, omitting 
 3 rights for 
 
 mams, 3000 
 
 hours. 
 
 5 feet 
 per 
 hour. 
 
 3 41 
 
 7 0 
 
 Not sufficiently 
 long, at 74. 6d. 
 
 Total for 
 year 18 
 millions. 
 
 Ditto. 
 
 Ditto. 
 
 3 gas 
 holders, and 
 1 erecting. 
 
 •528 
 
 74 
 
 1,826 
 
 
 •75 
 
 25 
 
 2173 hours, 
 from August 
 
 to May. 
 All the vear, 
 4327 hours. 
 
 Ditto. 
 
 4 0 
 nearly 
 
 
 Lose about 17 J 
 per cent. 
 
 Ditto. 
 
 Ditto 
 
 Wet lime. 
 
 4 gas 
 holders. 
 
 •448 
 
 83 
 
 1,453 
 
 1-2 
 
 •925 
 
 3 
 
 Ditto. 
 
 3 0 
 nearly 
 
 
 Could not learn. 
 
 Ditto. 
 
 Ditto. 
 
 Ditto. 
 
 
 ■424 
 
 90 
 
 1,234 
 
 1-3 
 
 1-175 
 
 3 
 
 4327 hours, 
 all the year. 
 
 Ditto. 
 
 4 feet 
 per 
 hour. 
 
 Ditto. 
 
 4 0 
 4 0 
 
 12 0 
 12 0 
 
 Receive for public 
 and private lights 
 
 74. public, 44. 
 private, 84. ; few 
 meters used. 
 
 Ditto. 
 
 Total for 
 year 1000 
 
 millions. 
 
 Longest 
 
 night 
 4,910,000. 
 
 Total for 
 year 1460 
 
 millions. 
 
 Longest 
 night 
 7,120,000. 
 
 Ditto. 
 Ditto. 
 
 Ditto. 
 Ditto. 
 
 130 gas 
 holders. 
 
 176 gas 
 holders. 
 
 •412 
 •412 
 
 80 
 80 
 
 1,562 
 1,562 
 
 1-13 
 1-13 
 
 •84 
 •84 
 
 2| 
 21 
 
 Q2 
 
116 GAS-LIGHT. 
 
 Bude-light. — This brilliant mode of illumination has been so called from the 
 name of the residence in Cornwall of Mr. Goldsworthy Gurney, who obtained a 
 patent for it in the year 1 838. In its first form it consisted of a common Argand oil 
 flame or lamp of rather narrow circular bore, into the centre of whose wick a jet of 
 oxygen gas was admitted through a tube inserted in the middle of the burner. This 
 contrivance was not, however, new in this country, for a similar lamp, similarly sup- 
 plied with oxygen gas was employed by the celebrated Dr. Thomas Young in his 
 lectures at the Royal Institution of Great Britain for the purpose of illuminating a 
 solar microscope, or gas microscope, about 40 years ago, and I had done the same thing 
 in Glasgow in the year 1806 or 1807. When used as a light for lighthouses or for 
 other continuous illumination, it has been found to be too expensive and difficult to 
 manage. It was tried upon a good scale a few years ago both by the Trinity House 
 in Tower Hill, and in one of their lighthouses on the coast, as well as by the House 
 of Commons. The Masters of the Trinity did not find it to be essentially superior for 
 the use of their lighthouses to their old and ordinary plan of illumination with a 
 number of Argand lamps placed in the focus, or near the focus, of reflecting mirrors. 
 It was, after several expensive trials by them, and in the House of Commons, aban- 
 doned by both. 
 
 In the course of numerous experiments in the Trinity House, Tower Hill, Mr. 
 Gurney had occasion to examine the structure and see the performance of Mr. Fresnel's 
 compound Argand lamps which are used in the French lighthouses, furnished with 
 refracting lenses of peculiar forms which surround these lamps, and transmit their con- 
 centrated light in any desired horizontal direction along the surface of the sea. Two of 
 Mr. Fresnel's lamps are placed in the lamp apartment of the Trinity House. Each 
 consists of a series of 4, 5, or 6 concentric wicks in the same plane, supplied with oil 
 from the fountain below by means of a pumping mechanism, as in the well-known 
 Parisian lamps of Carcel and Gagneau. The effect of 4, 5, or 6 concentric flames thus 
 placed in close proximity to each other, with suitable supply of air through the interior 
 of the innermost tube and the interstices between the exterior ones, is, to increase the 
 heat in a very remarkable degree, and by this augmentation of the heat to increase pro- 
 portionably the light. For it has been long known that a piece of even incombustible 
 matter, such as a lump of brick, intensely heated, sends forth a most brilliant irradia- 
 tion of light. This fact was applied first to the purpose of illuminating objects by Pro- 
 fessor Hare, of Philadelphia, fully 40 years ago. By directing the very feebly lumin- 
 ous flame of the compound jet of hydrogen and oxygen upon a bit of clay, such as one 
 of Wedgwood's pyrometer pieces, a most vivid illumination was sent forth from it as 
 soon as it became intensely heated. More lately, a piece of lime has been used instead 
 of a bit of clay, as it is not so apt to change by the ignition, and affords, therefore, a 
 more durable effect. It is used in our modern gas microscopes. Mr. Gurney suggested 
 the use of lime for the above purpose in a work on chemistry which he published 
 more than twenty years ago. It was afterwards adopted by Mr. Drummond, in order 
 to make signal lights in the trigonometrical survey of the Board of Ordnance, and was 
 therefrom called the Drummond light, though he had no share whatever in the merit of 
 the invention. 
 
 The structure of the Fresnel lamp would naturally suggest to Mr. Gurney the idea 
 of trying the effect of a similar construction of an Argand gas lamp. But prior to the 
 execution of this scheme, he obtained a second patent in the year 1839, for increasing 
 the illuminating power of coal gas by feeding its flame in a common Argand burner 
 with a stream of oxygen. But here a serious difficulty occurred. The stream of oxygen, 
 when admitted into the centre of such a flame, instead of augmenting its quantity of 
 light, destroys it almost entirely. This result might have been predicted by a person 
 well versant in the principles of gas illumination, as long ago expounded in Sir Hum- 
 phrey Davy's admirable Researches on Flame. This philosopher demonstrated that 
 the white light of gas-lamps, as also of oil lamps, was due to the vivid ignition of solid 
 particles of carbon evolved by the igneous decomposition of the hydro-carburet, either 
 in the state of gas or vapour ; and that if, by any means, these particles were not de- 
 posited, but burned more or less completely in the moment or act of their evolution 
 from the hydro- carburet, then the illumination would be more or less impaired. Mr. 
 Gurney, on observing this result, sought to obviate the evil, by charging the coal gas, 
 with the vapour of naphtha. Thus a larger supply of hydro- carburet, and of carbon of 
 course, being obtained, the flame of the naphthalised gas, admitted with advantage 
 the application of oxygen gas, for the increase of its light ; on the principle of greater 
 intensity of ignition, and consequently of light, being produced by the burning of carbon 
 in oxygen than in common air, as had been long known to the chemical world. But 
 an obstruction to the permanent employment of naphthalised gas was experienced by 
 Mr. Gurney, from the deposition of liquid naphtha in the pipes of distribution. He 
 was therefore induced to renounce this project. He then resorted to the use of coal ga?, 
 
GELATINE. 117 
 
 purified in a peculiar way, and burned in compound Argand lamps, consisting of two 
 or more concentric metallic rings, perforated with rows of holes in their upper surfaces, 
 having intervals between the rings for the admission of a proper quantity of air, the 
 burner being enclosed in a glass chimney at the level of the flame, surmounted by a 
 tall iron chimney. Between these two chimneys, a certain space is left for the admis- 
 sion of air, and to favour draught and ventilation. The intensity and whiteness of the 
 cylinder of light produced by the combustion of coal gas in this lamp are truly ad- 
 mirable, and form such an improvement in illumination for streets, churches, public 
 rooms, and private houses, as to merit the protection of a patent, and the encourage- 
 ment of the public at large. 
 
 General Estimate of Sizes, Number of Concentrics, Consumption of Gas, and Com- 
 parative Light. 
 
 Size. 
 
 Number of 
 Concentrics. 
 
 Bude Consump- 
 tion per Hour. 
 
 Height of 
 Flame. 
 
 Comparative Light. 
 
 Argand 
 Consumption 
 per Hour. 
 
 Inches. 
 
 
 Feet. 
 
 Inches. 
 
 Inches. 
 
 15-hole argands. 
 
 Cubic feet. 
 
 
 2 
 
 10 
 
 6 
 
 3 
 
 5 
 
 30 
 
 3 
 
 2 
 
 16 
 
 4 
 
 3 
 
 8 
 
 48 
 
 H 
 
 2 
 
 21 
 
 6 
 
 3 
 
 10 
 
 60 
 
 4 
 
 2 
 
 26 
 
 4 
 
 3 
 
 12 
 
 72 
 
 
 2 
 
 33 
 
 7 
 
 3 
 
 15 
 
 90 
 
 5 
 
 3 
 
 40 
 
 0 
 
 n 
 
 18 
 
 108 
 
 51 
 
 3 
 
 43 
 
 5 
 
 H 
 
 20 
 
 120 
 
 6 
 
 3 
 
 56 
 
 4 
 
 4 
 
 24 
 
 144 
 
 GELATINE. The substance produced by boiling the skin of animals in water, 
 which in its crude but solid state is called glue, and when a tremulous semi-liquid, size. 
 The latter preparation is greatly used by the paper-makers, and was much improved by the 
 following process, for which Mr. William Rattray obtained a patent in May, 1838. The 
 parings and scrows of skins are steeped in water till they begin to putrefy ; they are 
 then washed repeatedly in fresh water with the aid of stampers, afterwards subjected, in 
 wooden or leaden vessels, to the action of water strongly impregnated with sulphurous 
 acid for from 12 to 24 hours; they are now drained, washed with stampers in cold 
 water, and next washed with water of the temperature of 120° F., which is poured upon 
 them and run off very soon to complete their purification. The scrows are finally con- 
 verted into size, by digestion in water of 120° for 24 hours ; and the solution is made 
 perfectly fine by being strained through several thicknesses of woollen cloth. They must 
 be exhausted of their gelatinous substance, by repeated digestions in the warm water. 
 The claim is for the sulphurous acid, which, while it cleanses, acts as an antiseptic. — 
 Newton's Journal, xiv. 173. 
 
 A fine gelatine for culinary uses, as a substitute for isinglass, is prepared by Mr. 
 Nelson's patent, dated March, 1839. After washing the parings, &c.,of skin, he scores 
 their surfaces, and then digests them in a dilute caustic soda lye during ten days. 
 They are next placed in an air-tight vat, lined with cement, kept at a temperature of 
 70° F. ; then washed in a revolving cylinder apparatus with plenty of cold water, and 
 afterwards exposed to the fumes of burning sulphur (sulphurous acid) in a wooden 
 chamber. They are now squeezed to expel the moisture, and finally converted into 
 soluble gelatine by water in earthen vessels, enclosed in steam cases. The fluid gelatine 
 is purified by straining it at a temperature of 100° or 120° F. I have examined this 
 patent gelatine, and found it to be remarkably good, and capable of forming a fine 
 calf's foot jelly. 
 
 Very recently a very beautiful sparkling gelatine has been prepared under a patent 
 granted to Messrs. J. and G. Cox, of Edinburgh. By their process the substance is 
 rendered perfectly pure, while it possesses a gelatinizing force superior even to isinglass. 
 It makes a splendid calves' feet jelly and a milk-white blanc-mange. The patentees also 
 prepare a semi-solid gelatine, resembling jujubes, which readily dissolves in warm 
 water, as also in the mouth, and may be employed to make an extemporaneous jelly. 
 
 The gelatine of bones may be extracted best by the combined action of steam 
 and a current of water trickling over their crushed fragments in a properly con- 
 structed apparatus. When the gelatine is to be used as an alimentary article, the 
 bones ought to be quite fresh, well preserved in brine, or to be dried strongly by a 
 stove. Bones are best crushed by passing them between grooved iron rolls. The 
 cast-iron cylinders in which they are to be steamed, should be three times greater in 
 length than in diameter. To obtain 1 000 rations of gelatinous soup daily, a charge 
 
118 
 
 GELATINE. 
 
 of four cylinders is required; each being 2\ feet long, by 14 inches wide, capable of 
 holding 70 lbs. of bones. These will yield each hour about 20 gallons of a strong 
 jelly, and will require nearly 1 gallon of water in the form of steam, and 5 gallons 
 of water to be passed through them in the liquid state. The 5 quarts of jelly pro- 
 duced houi-ly by each cylinder, proceeds from the 1 quart of steam-water and 4 quarts 
 of percolating water. 
 
 The boiler should furnish steam of about 223° Fahr., at a pressure of about 4 lbs. 
 on the square inch. 
 
 In jig. 70. A, B, C, D, represents a vertical section of the cylinder; G, H, I, K, a 
 
 section of the basket or cage, as filled with the bruised bones, inclosed in the cylinder ; 
 E, C, C, the pipe which conducts the steam down to the bottom of the cylinder ; L, S, 
 a pipe for introducing water into the interior ; M, a stopcock for regulating the 
 quantity of water (according to the force of the steam pressure within the apparatus), 
 which should be 2>\ quarts per hour ; N is a tube of tin plate fitting tightly into the 
 >* part S of the pipe L ; it is shut at R, and perforated below with a hole ; it is 
 - inserted in its place, after the cage full of bones has been introduced. Fig. 71. is an 
 
 elevation of the apparatus. A, B, C, D, represent the four cylinders raised about 
 20 inches above the floor, and fixed in their seats by screws ; h, h, are the lids ; 
 p, g, tubulures or valves in the lids ; i, ring junction of the lid ; p, a thermometer ; 
 f, /, stop-cocks for drawing off the jelly ; n, n, small gutters of tin-plate ; m, the 
 
GUANO. 
 
 119 
 
 general gutter of discharge into the cistern b ; o, a block and tackle for hoisting the 
 cageful of bones in and out. Fig, 72. is an end view of the apparatus ; a, the main 
 
 steam-pipe ; a, b, c, c, branches that conduct the 
 steam to the bottom of the cylinder ; o, the 
 tackle for raising the cage ; s, stopcock ; n, small 
 gutter ; m, main conduit ; b, cistern of reception. 
 
 When a strong and pure jelly is wished for, 
 the cylinder charged with the bones is to be 
 wrapped in blanket stuff ; and whenever the 
 grease ceases to drop, the stopcock which admits 
 the cold water is to be shut, as also that at the 
 bottom of the cylinder, which is to be opened only 
 at the end of every hour, and so little as to let 
 the gelatinous solution run out, without allow- 
 ing any of the steam to escape with it. 
 
 Butcher's meat contains on an average in 100 
 pounds, 24 of dry flesh, 56 of water, and 20 of 
 bones. These 20 pounds can furnish 6 pounds 
 of alimentary substance in a dry state ; whenco 
 it appears that, by the above means, one fourth 
 more nutritious matter can be obtained than is 
 usually got. I am aware that a keen dispute 
 has been carried on for some time in Paris, be- 
 tween the partisans and adversaries of gelatine 
 as an article of food. It is probable that both 
 parties have pushed their arguments too far. 
 ' " Calf's-foot jelly is still deemed a nutritious 
 
 article by the medical men of this country, at least, though it is not to be trusted 
 to alone, but should have a due admixture or interchange of fibrine, albumine, 
 caseum, &c. 
 
 GILDING. See Electro- Metallurgy. 
 
 GLASS. Duty collected on it in the United Kingdom. In 1831, 732,4551 ; 
 1832, 751,448/. ; 1833, 828,558/. ; 1834, 916,822/. ; 1835, 966,121/. ; 1836, 933,281/. ; 
 1837, 903,846/. ; 1838, 879,859/. ; 1839, 868,193/.; 1840, 965,967/. 
 
 Crystal glass is rapidly corroded by the sulphate of ammonia, at a heat of 600° F. 
 
 GLOVE. See Leather. 
 
 GLUCOSE, the name given to grape and starch sugar by M. Dumas. 
 GROWAN. The name given by the Cornish miners to granite, and to rocks of 
 like structure. 
 
 GUANO. This extraordinary excrementitious deposit of certain sea-fowls, which 
 occurs in immense quantities upon some parts of the coasts of Peru, Bolivia, and 
 Africa, has lately become an object of great commercial enterprise, and of intense 
 interest to our agricultural world. Four or five years ago it was exhibited and talked 
 of merely as a natural curiosity. No one could then have imagined that in a short 
 period it would be imported from the coasts of the Pacific in such abundance, and at 
 such a moderate price, as to cheer by its fertilizing powers the languid and depressed 
 spirits of the farmers throughout the United Kingdom. Such, however, is now the 
 result, as attested by the concurring Reports of almost all the Agricultural Societies 
 of Great Britain and Ireland. No less than 28,500 tons of guano have been already 
 imported from Peru and Bolivia, 1500 from Chile, and 8000 from Africa, altogether 
 38,000 tons, while more is on the way. The store of it, laid up from time immemorial 
 in the above localities, seems to be quite inexhaustible; especially since it is receiving 
 constant accessions from myriads of cormorants, flamingos, cranes, &c. 
 
 Having been much occupied with the chemical analyses of guano during the last 
 two years for Messrs. Gibbs, of London, and Messrs. Myers, of Liverpool, who are the 
 co-agents of the Peruvian and Bolivian governments, I have enjoyed favourable 
 opportunities of examining samples of every description, and hope to show that many 
 of the analyses of guano hitherto published have been made upon specimens not in 
 their normal or sound state, like the best imported by the above houses from Chincha and 
 Bolivia, but in a certain state of eremacausis and decay. 
 
 Huano, in the language of Peru, signifies dung : a word spelt by the Spaniards, guano. 
 The natives have employed it as a manure from the remotest ages, and have by its means 
 given fertility to the otherwise unproductive sandy soils along their coasts. While Peru 
 was governed by its native Incas, the birds were protected from violence by severe laws. 
 The punishment of death was decreed to the persons who dared to land on the guani- 
 ferous islands during the breeding period of the birds, and to all persons who destroyed 
 them at any time. Overseers were appointed by the government to take care of the 
 
120 
 
 GUANO. 
 
 guano districts, and to assign to each claimant his due share of the precious dung. The 
 celebrated Baron Von Humboldt first brought specimens to Europe in 1804, which he 
 sent for examination to Fourcroy, Vauquelin, and Klaproth, the best analytical chemists of 
 the day; and he spoke of it in the following terms: — " The guano is deposited in 
 layers of 50 or 60 feet thick upon the granite of many of the South-sea islands off the 
 coast of Peru. During 300 years the coast birds have deposited guano only a few 
 lines in thickness. This shows how great must have been the number of birds, and 
 how many centuries must have passed over in order to form the present guano beds." 
 The strata have undergone many changes, according to the length of time they have 
 been deposited. Here and there they are covered with siliceous sand, and have thus 
 been protected from the influence of the weather ; but in other places, they have lain 
 open to the action of light, air, and water, which have produced important changes 
 upon them. Fresh guano is of a whitish or very pale drab colour, but it becomes pro- 
 gressively browner and browner by the joint influence of the above three atmospheri- 
 cal agents. Only one guano examined by Fourcroy and Vauquelin was fonnd to con- 
 tain a fourth of its weight of uric acid combined with ammonia, whence that appears 
 to have been well selected by Baron Von Humboldt. They also found phosphates of 
 ammonia, of lime, with urate and oxalate of ammonia, and some other constituents of 
 little value in agriculture. Klaproth's analysis reported 16 per cent, of urate of ammonia, 
 no less than 12 7 5 of oxalate of lime, 10 of phosphate of lime, 32 of clay and sandi 
 with 28*75 of water and indeterminate organic matter. From the great proportion of 
 clay and sand, Klaproth's sample of guano was obviously not genuine. I have met 
 with no specimen of Peruvian guano that contained any appreciable quantity of clay, 
 and none that contained above 4 or 5 per cent, of siliceous sand. 
 
 To Mr. Bland, of the firm of Messrs. Myers and Co., I am indebted for the follow- 
 ing valuable information : — 
 
 The Chincha islands, which afford the best Peruvian guano, are three in number, and 
 lie in one line from north to south, about half a mile apart. Each island is from 5 to 
 6 miles in circumference, and consists of granite covered with guano in some places to 
 a height of 200 feet, in successive horizontal strata, each stratum being from 3 to 1 0 
 inches thick, and varying in colour from light to dark brown. No earthy matter 
 whatever is mixed with this vast mass of excrement. At Mr. Bland's visit to these 
 islands in 1842, he observed a perpendicular surface of upwards of 100 feet of perfectly 
 uniform aspect from top to bottom. In some parts of these islands, however, the deposit 
 does not exceed 3 or 4 feet in thickness. In several places, where the surface of the 
 guano is 100 feet or more above the level of the sea, it is strewed here and there with 
 masses of granite, like those from the Alpine mountains, which are met with on the slopes 
 of the Jura chain. These seem to indicate an ancient formation for the guano, and terra- 
 queous convulsions since that period. No such granite masses are found imbedded 
 within the guano, but only skeletons of birds. 
 
 The good preservation of the Chincha guano is to be ascribed to the absence of rain ; 
 which rarely, if ever, falls between the latitude of 14° south, where these islands lie, 
 about 10 miles from the main land, and the latitude of Paquica, on the coast of Bo- 
 livia, in 21 S. L. By far the soundest cargoes of guano which I have analysed have 
 come from Chincha and Bolivia. Beyond these limits of latitude, where rain falls in 
 greater or less abundance, the guano is of less value — and what has been imported from 
 Chile has been found by me far advanced in decay — most of the ammonia and azotized 
 animal substances having been decomposed by moisture, and dissipated in the air (by the 
 eremacausis of Liebig), leaving phosphate of lime largely to predominate along with 
 effete organic matter. The range of the American coast from which the guano is 
 taken must therefore be well considered ; and should not extend much beyond the 
 Chincha islands as the northern limit, and Paquica, in Bolivia, as the southern. 
 
 The relative estimation of guano and nitrate of soda among the Peruvians is well 
 shown by the following facts communicated to me by Mr. Bland : — " Near the coast of 
 Peru, about 45 miles from Iquique (the shipping port of guano) there is the chief deposit 
 of nitrate of soda. The farmers, who collect and purify this natural product, carry it 
 to the place of shipment, and always require to be paid in return with an equivalent 
 quantity of guano, with which they manure their land, to the exclusion of the far 
 cheaper nitrate of soda. We cannot be surprised at this preference, when we learn that 
 in the valley of Chancay, about 40 miles distant from Lima, the soil produces, when 
 farmed with irrigation in the natural way, a return upon maize of only 15 for 1 ; 
 whereas, with the aid of guano, it produces 300 for 1 ! Hence the Peruvian proverb : 
 — Huano, though no saint, works many miracles. 
 
 In the pamphlet recently published by Messrs. Gibbs and Myers, entitled " Peruvian 
 and Bolivian Guano, its nature, properties, and results," we have a very interesting 
 view of the best established facts with regard to its operation and effects upon 
 every variety of soil, and in every variety of circumstance, as ascertained by the most 
 
GUANO. 
 
 121 
 
 intelligent agriculturists of the United Kingdom. The general conclusion that may- 
 be fairly deduced from the whole evidence is, that good guano will, under judicious 
 application, increase the crops of grain, turnips, potatoes, and grass by about 33 per 
 cent. ; and with its present price of 10/. per ton, at a cost considerably under the 
 average cost of all other manures, whether farm-yard dung and composts, or artificial 
 compounds. Guano is, moreover, peculiarly adapted to horticultural and floricultural 
 improvement, by its relative cleanliness and facility of application. 
 
 The following observations upon guano, by Dr. Von Martius, of Munich, addressed 
 to the agricultural society of Bavaria, deserve attention. Among animal manures, 
 says he, it clearly claims the first place. It is uncommonly rich in ammoniacal salts, 
 which act very favourably on vegetation. The ease with which these salts are decom- 
 posed, and exhale their ammonia into the air, is by him assigned as the reason whv 
 plants manured with guano generally present early in the" morning accumulations of 
 dew on the points of their leaves. The guano absorbs the atmospheric vapour, as well 
 as carbonic acid ; whereby it becomes so valuable a manure in dry barren regions. If 
 we compare guano with other excrementitious manures, we shall find it far preferable 
 to those afforded by man or other mammalia, which do not generally contain more than 
 20 per cent, of food that can be appropriated by plants. It is therefore 5 times better 
 than night-soil, and also very superior to the French poudrette, (which, being dried night- 
 soil,) loses, through putrefaction and evaporation, the greater proportion of its ammoniacal 
 elements. In birds, the excretions both of the kidneys and intestines are contained in 
 the cloaca ; whereby the volatile elements of the former get combined with the more 
 fixed components of the latter. The guano is also a richer manure, on account of its 
 being produced by sea-fowl, which live entirely on fish, without admixture of vegetable 
 matter. The exposure also of the guano as soon as deposited to the heat of a tropical 
 sun, in a rainless climate, prevents the components from fermenting, and mummifies them, 
 so to speak, immediately into a concrete substance not susceptible of decomposition 
 till it gets moisture ; whereas the dung of our dove-cots suffers a considerable loss by 
 exposure to our humid atmosphere. But in their action on vegetation, and in their 
 chemical composition, these two hird excrements are analogous. Davy found in fresh 
 dove-cote manure 23 parts in 100 soluble in water, which yielded abundance of car- 
 bonate of ammonia by distillation, and left carbonaceous matter, saline matter, princi- 
 pally common salt, and carbonate of lime as a residuum. Pigeons' dung readily fer- 
 ments, but after fermentation afforded only 8 per cent, of soluble matter, which gave 
 proportionably less carbonate of ammonia in distillation than the dung recently voided. 
 Dr. Von Martius proceeds to compare the proportion of soluble salts in guano and 
 pigeons' dung, and thinks that by that comparison alone he can establish the superiority 
 of the former ; but he should have considered that the insoluble urate of ammonia, 
 which is so powerful and copious a constituent of good guano, and is present in much 
 smaller proportion in pigeons' dung, is sufficient of itself to turn the balance greatly in 
 favour of the Peruvian manure. His general estimate however, that the manuring power 
 of genuine guano, is four times greater than that of pigeons' dung, is probably not wide 
 of the truth. Besides the above-mentioned constituents, guano derives no small por- 
 tion of its fertilizing virtue from the great store of phosphoric acid which it contains, 
 in various states of saline combination, with lime, magnesia, and ammonia. Of all the 
 principles furnished to plants by the soil, the phosphates are, according to Liebig, the 
 most important. They afford, so to speak, the bones and sinews of vegetable bodies, while 
 ammonia supplies them with their indispensable element, azote. Their carbon, hydrogen, 
 and oxygen are derived from the air and water. Those products of vegetation which 
 are most nutritious to man and herbivorous animals, such as bread -corn, beans, peas, and 
 lentils, contain the largest proportion of phosphates. The ashes of these vegetable sub- 
 stances afford no alkaline carbonates. A soil in which phosphates are not present, is 
 totally incapable of producing the above cereals. Agreeably to these views, Liebig 
 believes that the importation of 1 cwt. of guano is equivalent to the importation of 
 8 cwt. of wheat ; so that 1 cwt. of that manure assumes, with due culture, the form of 
 8 cwt. of substantial food for man. 
 
 Since all these testimonies concur to place this remarkable excrementitious product in 
 such high estimation, it becomes a paramount duty of the chemist to investigate its com- 
 position, and to discover certain means of distinguishing what may be termed the sound 
 or normal state of guano, from the decomposed, decayed, and effete condition. The 
 analysis by Fourcroy and Vauquelin of a sample of guano presented to them by Baron 
 Von Humboldt, gave the following composition in 100 parts : — 
 
 Urate of ammonia - - - - 9*0 
 
 Oxalate of ammonia - - - - 10-6 
 
 Oxalate of lime - - - - 7 0 
 
 Phosphate of ammonia - - - - 6*0 
 
 II 
 
122 
 
 GUANO. 
 
 Phosphate of ammonia and magnesia - - - 2 *6 
 
 Sulphate of pot sh - - - - 5*5 
 
 soda .- - - 3-3 
 
 Sal ammoniac - - - ^ 4-2 
 
 Phosphate of lime - - ? - 14*3 
 
 Clay and sand - - - - 47 
 
 Water and organic matters - - - .«• 82-3 
 
 How different are these constituents from those assigned by Klaproth,- — a no less skilful 
 analyst than the French chemists ! and how much this difference shows not only the 
 complexity of the substance, but its very variable nature ! 
 
 The general results of an analysis by professor Johnston, published in his paper on 
 guano, in the 3d part of the 2d vol. of the Journal of the Royal Agricultural Society 
 of England, are as follows : — 
 
 Ammonia - - - - 7*0 
 
 Uric acid - - - - - 0 8 
 
 "Water and carbonic and oxalic acids, &c. expelled by a red heat 51-5 
 
 Common salt, with a little sulphate and phosphate of soda - 11-4 
 
 Phosphate of lime, &c. - - - , 29 -3 
 
 100-0 
 
 The specimen of guano represented by this analysis must have been far advanced in 
 decomposition, as shown by the very scanty portion of uric acid ; and must have been 
 originally impure, {spurious ?) from the large proportion of common salt, of which 1 have 
 not found above 4 or 5 per cent, in any of the genuine guanos which I have had oc- 
 casion to analyze. In another sample, Professor Johnston found 44-4 of phosphate of 
 lime, with a little phosphate of magnesia, and carbonate of lime. These results resemble, 
 to a certain degree, those which I have obtained in analyzing several samples of Chilian 
 and African guanos, especially in the predominance of the earthy phosphates. The propor- 
 tion of ammonia which can be extracted by the action of hydrate of soda and quicklime, 
 at an elevated temperature, is the surest criterion of the soundness of the guano ; for by 
 this process we obtain not only the ready formed ammonia, from its several saline 
 compounds, but also the ammonia producible from its uric acid, and undefined animal 
 matter. These two latter quantities have been hitherto too little regarded by most 
 analysts, though they constitute the most durable fund of azote for the nutrition of 
 plants. Uric acid, and urate of ammonia, which contains 10-1 lths of uric acid, being 
 both nearly insoluble in water, and fixed at ordinary temperatures, continue to give out 
 progressively to plants in the soil, the azote, of which they contain fully one-third of 
 their weight. Under the influence of oxygen and a certain temperature, uric acid 
 passes through a very remarkable series of transformations ; producing allantoin, urea, and 
 oxalic acid, which eventually becomes carbonic acid. These changes are producible imme- 
 diately by the action of boiling water and peroxide of lead. From these metamorphoses, 
 we can readily understand how so much oxalate of ammonia and of lime is reported in 
 many analyses of guano, though none, I believe, is to be found in the normal state, as it 
 is occasionally imported from the Chincha Islands and Bolivia; nor were any oxalates 
 found in the dung of the garmet, as analyzed by Dr. Wollaston, or of the sea eagle, 
 according to the following analysis of Coiudet : — ammonia, 9 '21 per cent.; uric acid, 
 84*65; phosphate of lime, 6 - 13 = 100. The Peruvian sea-fowl, by feeding exclusively 
 on fish, would seem to swallow a large proportion of earthy phosphates ; since, in 
 the purest guano that has come in my way, I have found these salts to amount to 
 from 10 to 15 per cent. 
 
 Dr. Von Martius proposes to use the degree of solubility of the guano in water as a good 
 criterion of its quality; but this is a most fallacious test. Sound guano contains from 15 
 to 25 per cent, of insoluble urate of ammonia ; nearly as much undefined animal matter, 
 along with from 15 to 20 of earthy phosphates, leaving no more than 50 or 55 percent, 
 of soluble matter, exclusive of moisture ; whereas decayed guano yields often 60 or 70 
 per cent, of its weight to water, in consequence of the uric acid and animal matter 
 being wasted away, and the large portion of moisture in it, the latter amounting very 
 often to from 25 to 35 per cent. The good Peruvian guano does not lose more than 
 from 7 to 9 per cent, by drying, even at a heat of 212° F. ; and this loss necessarily 
 includes a little ammonia. Each analysis of guano executed for the information of the 
 farmer should exhibit definitely and accurately to at least 1 per cent : — 
 
 1. The proportion of actual ammonia. 
 
 2. The proportion of ammonia producible also from the uric acid and azotized 
 animal matter present ; and which may be called the potential ammonia. This is a 
 
GUANO. 
 
 123 
 
 most valuable product, which is, however, to be obtained only from well-preserved 
 dry guano. 
 
 3. The proportion of uric acid, to which, if l-10th of the weight be added, the quan- 
 tity of urate of ammonia is given. 
 
 4. The proportion of the phosphates of lime and magnesia. 
 
 5. The proportion of fixed alkaline salts, distinguishing the potash from the soda 
 salts ; the former being more valuable, and less readily obtainable, than the latter can be 
 by the use of common salt. Wheat, peas, rye, and potatoes require for their successful 
 cultivation, a soil containing alkaline salts, especially those of potash. 
 
 6. The proportion of sandy or other earthy matter, which, in genuine guano, care- 
 fully collected, never exceeds 2 per cent, and that is silica, g 
 
 7- The proportion of water, separable by the heat of 212° F. 
 
 The farmer should never purchase guano except its composition in the preceding 
 particulars be warranted by the analysis of a competent chemist. He should cork up 
 in a bottle a half-pound sample of each kind of guano that he buys ; and if his crop 
 shall disappoint reasonable expectation, he should cause the samples to be analyzed ; 
 and should the result not. correspond to the analysis exhibited at the sale, he is fairly 
 entitled to damages for the loss of his labour, rent, crop, &c. The necessity of follow- 
 ing this advice will appear on considering the delusive, if not utterly false analyses, 
 under which Gargoes of guano have been too often sold. In a recent case which came 
 under my cognizance, in consequence of having been employed professionally to analyze 
 the identical cargo, I found the guano to be nearly rotten and effete ; containing alto- 
 gether only 2i per cent, of ammonia, A per cent, of urate of ammonia, nearly 9 of sea 
 salt, 24 of water, and 45^, of earthy phosphates. Now, this large cargo, of many 
 hundred tons, fetched a high price at. a public sale, under the exhibition of the follow- 
 ing analysis by a chemist of some note — 
 
 Urate of ammonia, ammoniacal salts, and decayed animal matter 17 - 4 
 
 Phosphate of lime, phosphate of magnesia, and oxalate of lime 48*1 
 
 Fixed alkaline salts .... io-8 
 
 Earthy and stony matter - - - 1 *4 
 
 Moisture - - - - - 22-3 
 
 100 0 
 
 The purchasers, I was told by the broker, bought it readily under a conviction that 
 the guano contained 17'4 of ammonia, though the proportion of ammonia is not stated, 
 but merely mystified, and adroitly confounded with the decayed animal matter. 
 
 By the following hypothetical analysis, much guano has been well sold : — 
 
 " Bone earth, 35 ; lithic acid, &c, 15 ; carbonate of ammonia, 14 ; organic matter, 36 
 = 100." I am quite certain that no sample of guano can contain 14 per cent, of carbonate 
 of ammonia — a very volatile salt. We shall see presently the state of combination in 
 which the ammonia exists. It may contain at the utmost 4 or 5 per cent, of the carbo- 
 nate ; but such guano must have been acted upon powerfully by humidity, and will 
 therefore contain little or no uric acid. 
 
 In the very elaborate examination of guano by T. Oellacher, apothecary at Inns- 
 bruck, published in a recent number of Buchner's Repertorium of Pharmacy, it is said, 
 that if a glass rod dipped into muriatic acid be held over guano, strong fumes are de- 
 veloped ; and the solution of guano has an alkaline reaction with litmus-paper. These 
 phenomena evidently indicate the presence of carbonate of ammonia, and of course a 
 partially decomposed guano; for sound Chincha and Bolivian guanos have an acid re- 
 action, proceeding from the predominance of phosphoric acid. Farmers frequently 
 judge of the goodness of guano by the strength of the ammoniacal odour; but in this 
 judgment they may egregiously err, for the soundest guano has no smell of ammonia 
 whatever ; and it begins to give out that smell only when it is more or less decomposed 
 and wasted. 
 
 Oellacher could find no evidence of urea in his guano ; I have obtained fully 5 per 
 cent, of this substance from good Peruvian guano. 
 I shall now describe my own system of analysis : — 
 
 1. In every case I determine, first of all, the specific gravity of the guano; which I 
 take by means of spirits of turpentine, with a peculiar instrument contrived to render 
 the process easy and precise. If it exceeds 1*75 in density, water being 1-0, it must 
 contain sandy impurities, or has an excess of earthy phosphates, and a defect of azotized 
 animal matter. 
 
 2. I triturate and digest 200 grains of it with distilled water, filter, dry the in- 
 soluble matter, and weigh it. 
 
 3. The above solution, diffused in 2000 gr. measures, is examined as to its specific 
 gravity, and then with test paper, to see whether it be acid or alkaline. 
 
 R 2 
 
124 
 
 GUANO. 
 
 4. One half of this solution is distilled along with slaked lime in a matrass con- 
 nected with a small quintuple globe condenser, containing distilled water, and im- 
 mersed in a basin of the same. As the condensing apparatus terminates in a water- 
 trap, no part of the ammonia can be lost ; and it is all afterwards estimated by a pecu- 
 liar meter, whose indications make manifest one hundredth part of a grain. 
 
 5. The other half of the solution is mixed with some nitric acid, and divided into 3 
 equal portions. 
 
 a, the first portion, is treated with nitrate of barytes, and the resulting sulphate of 
 barytes is collected, ignited, and weighed. 
 
 b, the second portion, is treated with nitrate of silver, and the resulting chloride of 
 silver ignited and weighed. 
 
 c, the third portion, has a certain measure of a definite solution of ferric nitrate 
 mixed with it, and then ammonia in excess. From the weight of the precipitated sub- 
 phosphate of iron after ignition, the known amount of oxide used being deducted,' 
 the quantity of phosphoric acid in the soluble portion of the guano becomes known. 
 
 d, the three above portions are now mixed, freed by a few drops of dilute sulphuric 
 and hydrochloric acids from any barytes and silver left in them, and then tested by 
 nitrate of lime for oxalate of ammonia. The quantity of oxalate of lime obtained, de- 
 termines that point. 
 
 6. The last liquor filtered, being freed from any residuary particles of lime by oxalate 
 of ammonia, is evaporated to dryness and ignited, to obtain the fixed alkaline matter. 
 This being weighed, is then dissolved in a little water, neutralized with acid, and treated 
 with soda-chloride of platinum. From the quantity of potash-chloride of platinum, which 
 precipitates, after being filtered, dried, and weighed, the amount of potash present is 
 deducted — the rest is soda. These bases may be assigned to the sulphuric, hydro- 
 chloric, and phosphoric acids, in proportions corresponding to their respective affinities. 
 
 7. The proportion of organic matter in the above solution of guano, is determined 
 directly by evaporating a certain portion of it to dryness, and igniting. The loss of 
 weight, minus the ammonia and oxalic acid, represents the amount of organic matter. 
 
 8. A second portion of a solution of the guano is evaporated to dryness by a gentle 
 steam heat, weighed, inclosed in a stout well-closed phial along with alcohol of 0-825, 
 and heated to 212°. After cooling, the alcoholic solution is decanted or filtered clear, 
 evaporated to dryness by a gentle heat, and weighed. This is urea, which may be 
 tested by its conversion into carbonate of ammonia, when heated in a test tube or small 
 retort. In this way, I have obtained from Bolivian guano, 5 per cent, of urea; a certain 
 proof of its entire soundness. 
 
 9. Analysis of the insoluble matter. One third of it is digested with heat in abundance 
 of Borax-water, containing T A g of the salt, filtered, and the filter dried by a steam heat. 
 The loss of weight indicates the amount of uric acid, which is verified by supersaturating 
 the filtrate with acetic or hydrochloric acid, thus precipitating the uric acid, throwing it 
 upon a filter, drying, and weighing it. This weight should nearly agree with the above 
 loss of weight, the small difference being due to soluble organic matter, sometimes called 
 geine and ulmic acid. The uric acid is evidenced, 1. by its specific gravity, which I 
 find to be only 1*25, as also that of the urate of ammonia ; 2. by its affording fine purple 
 murexide when heated in a capsule along with nitric acid, and then exposed to the 
 vapour of ammonia from a feather held over it ; 3. by its dissipation when heated, 
 without emitting an empyreumatic odour. 
 
 10. Another third of the solid matter is distilled along with half its weight of slaked 
 lime, and 10 times its weight of water, in the apparatus already described, and the am- 
 monia obtained from it estimated. 
 
 1 1. The remaining third having been ignited, is digested with a gentle heat in weak 
 hydrochloric acid, and the undissolved silica and alumina washed on a filter, dried, and 
 weighed. To the hydrochloric solution, dilute sulphuric acid is added, and the mixture 
 is heated till all the hydrochloric acid be expelled, with the greater part of the water. 
 Alcohol of 0850 is now poured upon the pasty residuum, and the whole, after being well 
 stirred, is thrown upon a filter. The phosphoric acid passes through, as also the magnesia 
 in union with sulphuric acid. The sulphate of lime, which is quite insoluble in spirits 
 of wine, being washed with them, is dried, ignited, and weighed. From the weight of 
 sulphate of lime, the quantity of phosphate of that earth, that w as present, becomes 
 known. 
 
 12. Ammonia in excess is now added to the filtrate, which throws down the granular 
 phosphate of ammonia and magnesia. After washing and drying this powder at a heat 
 of 150°, its weight denotes the quantity of that compound in the guano. 
 
 13. To the filtered liquor (of 12.), if a little ammonia be added, and then muriate 
 of magnesia be slowly dropped in, phosphate of ammonia and magnesia will precipitate, 
 from the amount of which the quantity of phosphoric acid may be estimated. 
 
 14. The proportion of oxalate of lime is determined by igniting the washed residuum 
 
GUANO. 
 
 125 
 
 (of 9.), and placing it in an apparatus for estimating the quantity of carbonic acid given 
 off in dissolving carbonate of lime. The apparatus, either Jig. 1. or 2. described in 
 my little Treatise on Alkalimetry, will serve that purpose well. I have rarely ob- 
 tained more than ^ gr. of carbonic acid from the insoluble residuum of 100 gr. of good 
 guano, and that corresponds to less than \\ per cent, of oxalate of lime in the guano. 
 Sometimes no effervescence at all is to be perceived in treating the washed residuum 
 with acid after ignition. 
 
 15. The carbonate of ammonia in guano is readily determined by filtering the solu- 
 tion of it in cold water, and neutralising the ammonia with a test or alkalimetrical acid. 
 (See the Treatise on Alkalimetry above referred to.) 
 
 16. Besides the above series of operations, the following researches must be made to 
 complete our knowledge of guano. The insoluble residuum (of 10.) which has been 
 deprived by two successive operations of its uric acid and ammonia, may contain 
 azotized organic matter. It is to be therefore well dried, mixed with 5 times its weight of 
 the usual mixture of hydrate of soda and quicklime, and subjected to gentle ignition 
 in a glass or iron tube closed at one end, and connected at the other with an ammonia 
 condensing apparatus. The amount of ammonia being estimated by a proper ammonia 
 meter, represents the quantity of azote, allowing 14 of this element for 17 of ammonia, 
 being the potential ammonia corresponding to the undefined animal matter. In a sample 
 of Peruvian guano I obtained 5 per cent, of ammonia from this source. 
 
 17. The whole quantity of ammonia producible from guano is to be determined by 
 gently igniting 25 gr. of it well dried, and mixed with 10 times its weight of the mix- 
 ture of hydrate of soda and quicklime (2 parts of the latter to 1 of the former). The 
 ammonia disengaged is condensed and measured, as described above. 
 
 18. The ready formed ammonia is in all cases determined by distilling a mixture of 
 100 gr. of it with 50 gr. of slaked lime, condensing the disengaged ammonia, and 
 estimating it exactly by the meter. 
 
 19. The relation of the combustible and volatile to the incombustible and fixed 
 constituents of guano, is determined by igniting 100 gr. of it in a poised platinum 
 capsule. The loss of weight denotes the amount of combustible and volatile matter, 
 including the moisture, which is known from a previous experiment. 
 
 20. The insoluble matter is digested in hot water, thrown upon a filter, dried, and 
 weighed. The loss of weight is due to the fixed alkaline salts, which, after concen- 
 trating their solutions, are investigated by appropriate tests — 1. nitrate of barytes for 
 the sulphates ; 2. nitrate of silver for the chlorides and sulphates ; and 3. soda-chloride of 
 platinum, for distinguishing the potash from the soda salts. 
 
 21. The insoluble matter (of 20.) is digested with heat in dilute nitric or hydro- 
 chloric acid, and the whole thrown upon a filter. The silica which remains on the 
 filter is washed, ignited, and weighed. The lime, magnesia, and phosphoric acid may be 
 determined as already pointed out. 
 
 22. I have endeavoured to ascertain if muriate of ammonia be present in guano, by 
 evaporating its watery solution to dryness, and subliming the residuum, but I have 
 never obtained a satisfactory portion of sal ammoniac ; and therefore I am inclined 
 to think there is little of it. The quantity of chlorine to be obtained from 
 guano is too inconsiderable to lead to a suspicion of its presence, except in com- 
 bination with sodium and potassium. Phosphate of soda is also a doubtful product — 
 but if present, it may be obtained from the saline matter (of 20.), by acidulating it with 
 nitric acid ; precipitating first with nitrate of barytes, next with nitrate of silver, taking 
 care to use no excess of these two re-agents, then supersaturating the residuum with 
 ammonia, and adding acetate of magnesia, when the characteristic double phosphate 
 of this earth should fall, in case phosphate of soda be present. 
 
 By the preceding train of researches, all the constituents of this complex product may 
 be exactly disentangled and estimated ; but they manifestly require much care, patience, 
 time, and dexterity, and also a delicate balance, particularly in vising the appropriate 
 apparatus for generating the potential ammonia, and for measuring the whole of this vola- 
 tile substance separated in the several steps of the process. It may be easily imagined 
 how little confidence can be reposed in many of the analyses of guano, framed, I fear, 
 too often with the view of promoting the sale of an indifferent or even spurious article 
 of commerce. 
 
 A. I shall now give in detail my analytical results upon three different samples 
 of a good South American guano ; and next the general results upon three samples 
 of African and Chilian guanos : — 
 
 I. Guano from Bolivia, imported by the Mary and Anne. This sample was taken 
 by myself, as an average out of several bags in the Lighter, before the cargo was landed. 
 Pale yellow brown colour, dry, partly pulverulent, partly concreted, in small lumps, 
 with a few small fragments of granite interspersed, and which, being obvious, were 
 separated prior to the analysis. Specific gravity of the pulverulent portion without 
 
126 
 
 GUANO. 
 
 the granite, 1 -60 ; of the concretions, 1*66 ; mean 1*63. Water digested on the former 
 portion is neutral to litmus, that on the latter is faintly acid. 
 
 2. 100 parts lose 6*5 by the heat of boiling water, and exhale no ammonia. When 
 digested and triturated with cold water, 30-5 parts dissolve, and 69 *5 are obtained after 
 drying, at 2 1 2° F. Of those 30 *5 parts, 6 *5 are therefore water, easily separable, and 
 24*5 parts are solid matter. 
 
 3. 100 parts, mixed with 9 times their weight of water, and 50 of lime, being distilled 
 in an alembic connected with the five-globe condenser, &c, afforded exactly 4-2 of am- 
 monia. 20 grains in fine powder, along with 200 of a mixture, consisting of 2 parts of 
 dry lime and 1 of hydrate of soda, were gently ignited in a combustion tube connected 
 with the ammonia condensing apparatus, and they produced 4*25 grains of ammonia — 
 equivalent to 21*25 from 100 grains of the guano. Thus only 4*2 per cent, of am- 
 monia were ready formed; while 17*05 lurked, so to speak, in their azotized elements. 
 
 From its aspect, and its want of ammoniacal odour, this guano, the first cargo re- 
 ceived from Bolivia, was imagined by the importers to be of bad quality ; and, accord- 
 ingly, my very favourable report of its analysis surprised them not a little, and rather 
 unsettled the little faith they at that time (January, 1843) had in chemistry. But 
 about a fortnight after the date of my report they received a letter from Peru, apprising 
 them of the excellence of that cargo of Bolivian guano, and of its being prized by the 
 Americans, as possessing fertilising powers in a pre-eminent degree. I consider this 
 guano therefore as a type of the substance in its best state. 
 
 II. The soluble matter was analyzed, in the manner already detailed, and was found 
 
 to consist of — 
 
 1. Urea - 5-00 
 
 2. Sulphate of potash - 7 '90 
 
 3. Chloride of sodium - 5 '00 
 
 4. Biphosphate of ammonia - - 5 *50 
 
 5. Oxalate of ammonia - - 0*60 
 
 24-0 
 
 In these ammoniacal salts there are only 1 *G5 parts of ammonia; but I obtained 2'55 
 grains in distilling the soluble matter of 100 grains of the guano. The remaining 0*9 
 parts, therefore, must have proceeded from the partial decomposition of the urea during 
 the long ebullition necessary to extract every particle of ammonia, in distilling the 
 guano along with lime. 
 
 III. The insoluble matter =69 *5 parts, was found to consist of — 
 
 1. Silica ------ 2-25 
 
 2. Subphosphate of lime - - - - 9 -00 
 
 3. Phosphate of magnesia and ammonia - - - 1 *25 
 
 4. Urate of ammonia - - - -15*27 
 
 5. Undefined azotized organic matter, affording, with the 14 parts 
 
 of uric acid, by ignition with hydrate of soda, 17*05 parts 
 
 of ammonia - - - - - 41*73 
 
 69*50 
 
 This result as to the large proportion of organic matter in the dried insoluble re- 
 siduum was verified by igniting a given quantity of it, when it was found to lose, out 
 of 69*5 parts, 57; corresponding to the 15*27 urate of ammonia, 41*73 of undefined 
 organic matter, and 0*08 of ammonia, in the double magnesian phosphate. In the 
 urate and double phosphate are 1 *35 of ammonia, which, with the 2*55, make 3 *9 parts ; 
 the other 0*3 parts may be traced to the urea. 
 
 As these results differ very considerably in many respects from those of the analyses 
 made by respectable German chemists* I was careful to verify them by manifold vari- 
 ations of the process, as follows : 
 
 1. The soluble matter, with acid reaction, of 100 parts of the lumps of the Bolivian 
 guano, was examined by per-acetate of iron and ammonia, for phosphoric acid, and 
 afforded 4 parts of it, which is more than had been found in the neutral pulverulent 
 guano. After the phosphoric acid was separated by that method, chloride of calcium 
 gave no cloud with the filtered liquor, proving that no oxalic acid was present in these 
 nodules. The washed insoluble matter, when gently ignited, and treated with dilute 
 nitric acid, afforded no effervescence whatever, and therefore showed that no oxalate of 
 lime had been present, for it would have become a carbonate. 
 
 It is necessary to determine from time to time the quantity of ferric oxide in the 
 
GUANO. 
 
 127 
 
 acetate or nitrate, as it is liable to be deposited from the solution, when this is kept for 
 some time. If this point be not attended to, serious errors would be committed in the 
 estimation of the phosphoric acid. 
 
 2. The quantity of uric acid was verified by several repetitions, and found to be 14 
 per cent. 
 
 3. The undefined organic matter, when deprived of the uric acid by prolonged 
 digestion with weak borax, being subjected to ignition along with hydrate of soda, 
 yielded the quantity of ammonia requisite to constitute the whole sum, that producible 
 from the uric acid also being taken into account. 
 
 4. The little lumps of the guano afforded, by distillation along with quicklime, .5*27 
 per cent, of ready formed ammonia, probably from the uric acid having been partially 
 decomposed by the moisture which had caused them to concrete. It is a curious fact, that 
 the solution of borax, from being of an alkaline, becomes of an acid reaction, after di- 
 gestion with the Bolivian guano. 
 
 5. For distinguishing and separating the soda salts from those of potash, I tried the 
 antimoniate of potash, according to Wackenroder's prescription, but I found reason to 
 prefer very much the crystallised soda-chloride of platinum, for that purpose. 
 
 From another specimen of the Bolivian guano, I extracted 3*5 per cent, of the 
 ammonia-phosphate of magnesia. 
 
 B. A sample of guano from the Chineha Islands, of nearly the same light colour 
 as the preceding, and the same dryness, being an early importation of 250 tons in 
 the present year, was subjected by me to a careful analysis. 
 
 1. The solution in water of this guano had an alkaline reaction from carbonate of am- 
 monia, which, being neutralised by test acid, indicated 0*34 per cent, of ammonia, 
 equivalent to about 1 of the smelling sesqui-carbonate. 
 
 2. Of this guano, 47 per cent, were soluble in water, and 53 per cent, remained, after 
 drying at a heat of 212° F. Of the above 47 parts, 8*5 were moisture in the guano. 
 
 3. The solution being acidulated with nitric acid, was treated with acetate of barytes, 
 in a quantity equivalent to the sulphuric acid present, and it afforded 1 2 parts of sul- 
 phate of barytes. With the filtered liquor, 700 water grain measures of ferric acetate 
 were mixed, and then ammonia in excess ; 18 "5 parts of washed and ignited sub-phosphate 
 of iron were obtained, from which deducting 8*8 parts present in the acetate, 9*7 
 remain as the quantity of phosphoric acid ; but 9 "7 of acid produce 13*25 of biphos- 
 phate of ammonia, which contain only 2*3 of ammonia, combined with 0*95 of water, 
 or its elements. From the alkaline excess in the guano, there can be no doubt, how- 
 ever, that it contained the sub-phosphate (found in the urine of Carnivora), and not the 
 bi-phosphate of that base. In this case, 9 *7 of acid produce 14*32 of dry saline com- 
 pound, containing 4*62 of ammonia, which, with the 0*34 of ammonia in the carbonate, 
 constitute a sum of 4*96. To the liquor freed from the phosphate of iron, and acidu- 
 lated with nitric acid, acetate of lime being added, 3*33 parts of oxalate of this base 
 were obtained, which are equivalent to 3 23 oxalate ammonia, containing 0*89 of 
 ammonia. 
 
 4. Nitrate of silver now produced from the filtered residual solution 8 parts of chlo- 
 ride, corresponding to nearly 3 of sal ammoniac, which contain nearly 0 95 of ammonia. 
 
 5. The 53 parts insoluble in water were digested with weak solution of borax at a boiling 
 heat, thrown on a filter, and the uric acid being precipitated from the filtrate by means 
 of a little hydrochloric acid, washed and dried, was found to weigh 13*5 parts. There 
 were left on the filter 36*5 parts, dried at 212° F., so that 3 parts of soluble organic 
 matter had passed through the filter. These 36*5 parts lost by ignition only 9 7 parts 
 in organic matter, became white, and afforded a very faint effervescence with hydro- 
 chloric acid, showing that a very little oxalate of lime had been present. 1 *25 parts of 
 silica were left after the action of the acid. To the solution of the 26*55 parts, sul- 
 phuric acid was added, and the mixture being heated to expel the hydrochloric acid and 
 the excess of the sulphuric, the residuary matter was digested and washed with dilute 
 alcohol, and thrown on a filter ; the solution of magnesia passed through, while the sul- 
 phate of lime remained. After ignition, this weighed 27*5 parts, equivalent to 22 of sub- 
 phosphate of lime. On supersaturating the filtrate with ammonia, 4*5 parts of the 
 magnesian ammonia phosphate were precipitated, containing 0*32 of ammonia, With 
 the 13*5 parts of uric acid, 1*23 of ammonia had been originally combined, forming 
 14*73 of urate. 
 
 6. 25 grains of the dry guano afforded, by ignition in the combustion-tube along with 
 200 grains of the mixed lime and hydrate of soda, 4*165 of ammonia, which correspond 
 to 16*66 in 100 parts of the dry, or to 15*244 in the natural state ; leaving therefore 5 
 parts for the quantity of potential ammonia, or of ammonia producible from the de- 
 composition of its azotized organic matter. This guano is therefore well adapted to 
 promote permanently the fertility of a soil. It yields besides to alcohol a notable 
 quantity of urea, which I did not think it worth while to determine quantitively, and 
 
128 
 
 GUANO. 
 
 from which undoubtedly a portion of the ammonia proceeded, in the distillation with 
 milk of lime. 
 
 7. 100 parts afforded by distillation with milk of lime, 10*2 of ammonia. 
 
 8. The total constituents of that guano, being tabulated, are — 
 
 I. Matter soluble in water - 47-00 
 
 consisting of — 
 
 Ammonia. 
 
 1 . Sulphate of potash, with a little sulphate of soda 
 
 6-00 
 
 
 2. Muriate of ammonia 
 
 3 -00 
 
 0*95 
 
 3. Phosphate of ammonia 
 
 - 14-32 
 
 4-62 
 
 4. Sesqui-carbonate of ammonia 
 
 1 -00 
 
 0-34 
 
 5. Sulphate of ammonia - - • 
 
 2-00 
 
 0-50 
 
 6. Oxalate of ammonia 
 
 3-23 
 
 0-89 
 
 8. Water - 
 
 8-50 
 
 
 9. Soluble organic matter and urea 
 
 8-95 
 
 
 
 47-00 
 
 
 IT. Matter insoluble in water 
 
 - 53-00 
 
 
 ting of — 
 
 
 
 I. Silica - 
 
 1-25 
 
 
 2. Undefined organic matter 
 
 9-52 
 
 
 3. Urate of ammonia - 
 
 . 14-73 
 
 1-23 
 
 4. Oxalate of lime - 
 
 1-00? 
 
 
 5. Subphosphate of lime 
 
 • 22-00 
 
 
 6. Phosphate of magnesia and ammonia 
 
 4-50 
 
 0-32 
 
 
 53-00 
 
 9-80 
 
 The remaining 1*25 of actual ammonia may be fairly traced to the partial decomposi- 
 tion of the urea during the distillation with lime; whereas the 5 per cent, of potential 
 ammonia proceeded from the transforming decomposition of the uric acid. 
 
 C. Foliated guano, from Peru, in caked pieces, the layers very thin, parallel, and 
 interspersed with white streaks. This guano was somewhat dense for a pure specimen, 
 having a specific gravity of 1 *7. The insoluble matter afforded by digestion with borax 
 water, no less than 25 -2 per cent, of pale yellow uric acid ; 9 of other combustible organic 
 matter, and 15 of earthy matter : consisting of silica, 3*5 ; phosphate of magnesia and 
 ammonia, 6*5 ; and only 5 of subphosphate of lime or hone earth. It lost 10 per cent, 
 when dried in a heat of 212° F. The remaining 30'8 parts soluble in water, had a 
 strong atid reaction, and afforded, by ferric acetate and ammonia, 6 of phosphoric acid, 
 equivalent to 9*7 of crystallized bi-phosphate of ammonia, after acetate of barytes had 
 separated the sulphuric acid. No less than 1 7 parts of chloride of silver were obtained, 
 by precipitating with nitrate of silver the liquor filtered from the phosphate of iron, and 
 acidulated with nitric acid. As the present is an accidental sample, and not an average 
 of any importation, I did not prosecute the research further. 
 
 D. Chincha Guano, of a somewhat darker colour than the preceding, and alkaline 
 reaction; specific gravity, 1-62. Digested with water and strained, 56*75 parts 
 remained after drying it at 212° F. The solution, evaporated and dried also at 212°, 
 afforded 31 25 of saline matter. This saline mass being mixed with four-fifths of its weight 
 of slaked lime, nine times its weight of water, and distilled, afforded of ammonia 14*28 
 per cent. Some chemists have prescribed potash instead of lime, for separating the am- 
 monia in distillation; but no person of intelligence who has made the experiment once 
 will choose to repeat it, because the potash forms with the organic matter of the guano a 
 viscid compound, that froths up like a mass of soap bubbles, and coming over with the 
 vapours, obstructs and vitiates the result. 
 
 2. When dried altogether by a steam heat, 100 parts lost 12 in moisture; whereas by 
 evaporating and drying the soluble matter by itself, the loss amounted to 16*3, no 
 doubt by the dissipation of some of the ammoniacal salts; for 100 parts of the entire 
 guano afford, by distillation with quicklime, 9 parts of ammonia, and by the trans- 
 forming decomposition with hydrate of soda and lime 16-25, indicating 7*25 of potential 
 ammonia, in addition to the 9 of ready formed. The insoluble matter of 100 parts 
 afforded to borax water a solution containing 16 5 of uric acid, corresponding to 18 of 
 urate of ammonia. There remained on the filter, after drying it at 212° F., only 33*8 
 parts ; so that about 5 parts of soluble organic matter had passed through the filter in 
 
GUANO. 
 
 129 
 
 the borax water. These 33*8 consisted of subphosphate of lime 17, magnesian phos- 
 phate of ammonia 5*5, silica 0*7, and combustible organic matter 10 6. 
 
 The ammonia in the soluble portion was in the state chiefly of phosphate; there was 
 merely a faint trace of oxalate of ammonia. 
 
 E. African Guano. — Among the many samples of African guano which I have 
 had occasion to analyze for the importers, none has contained any appreciable quantity 
 of uric acid, or by consequence of potential ammonia. The best afforded me 10 per 
 cent, of ready-formed ammonia, existing chiefly in the state of a phosphate, though they 
 all contain carbonate of ammonia, and have of consequence an alkaline reaction. The 
 said sample contained 21*5 of moisture, separable by a heat of 212° F. Its specific 
 gravity was so low as 1*57, in consequence of the large proportion of moisture in it. 
 It contained 23 per cent, of subphosphate of lime, 3 of magnesian phosphate of am- 
 monia, 1 of silica, and 1*5 of alkaline sulphate and muriate. The remaining 50 parts 
 consisted of decayed organic matter, with phosphate of ammonia, and a little carbonate, 
 equivalent to half a grain of ammonia, which is the largest quantity in such guanos. 
 Other African guanos have afforded from 24 to 36 of moisture ; no uric acid ; no po- 
 tential ammonia; but decayed organic matter ; from 5 to 7 of ready formed ammonia in 
 the state of phosphate, with a little carbonate; from 25 to 35 per cent, of subphosphate of 
 lime ; 5 or 6 of the magnesian phosphate of ammonia ; more or less oxalates from the 
 decomposition of the uric acid, and 3 to 5 per cent, of fixed alkaline salts. 
 
 F. The Chilian Guano gathered on the coast, already adverted to, contained a remark- 
 able proportion of common salt, derived probably from the sea spray. 
 
 The following is the General Report of the chemical examination of several 
 samples of guano, which I made for Messrs. Gibbs of London, and Messrs. Myers of 
 Liverpool. 
 
 u In these various analyses, performed with the greatest care, and with the aid of the 
 most complete apparatus for both inorganic and organic analysis, my attention has been 
 directed not only to the constituents of the guano which act as an immediate manure, 
 but to those which are admitted by practical farmers to impart durable fertility to the 
 grounds. The admirable researches of Professor Liebig have demonstrated that Azote, 
 the indispensable element of the nourishment of plants, and especially of wheat and 
 others abounding in gluten (an azotized product), must be presented to them in the state 
 of Ammonia, yet not altogether ammonia in the pure or saline form, for, as such, it is 
 too readily evaporated or washed away ; but in the dormant, or as one may say, in the 
 potential condition in contradistinction from the actual. Genuine Peruvian and Bolivian 
 guanos, like those which I have minutely analyzed, surpass very far all other species 
 of manure, whether natural or artificial, in the quantity of potential ammonia, and, 
 therefore, in the permanency of their action upon the roots of plants, while, in conse- 
 quence of the ample store of actual ammonia which they contain ready formed, they 
 are qualified to give immediate vigour to vegetation. Urate of ammonia constitutes a 
 considerable portion of the azotized organic matter in well-preserved guano ; it is 
 nearly insoluble in water, not at all volatile, and is capable of yielding to the soil, by its 
 slow decomposition, nearly one-third of its weight of ammonia. No other manure can 
 rival this animal saline compound. One of the said samples of guano afforded me no 
 less than 17 per cent, of potential ammonia, besides 4| per cent, of the actual or ready 
 formed ; others from 7 to 8 per cent, of ammonia in each of these states respectively. 
 The guanos which I have examined are the mere excrement of birds, and are quite free 
 from the sand, earth, clay, and common salt, reported in the analyses of some guanos, 
 and one of which (sand) to the amount of 30 per cent. I found myself in a sample of 
 guano from Chile. 
 
 " The Peruvian guano, moreover, contains from 10 to 25 per cent, of phosphate of 
 lime, the same substance as bone-earth, but elaborated by the birds into a pulpy con- 
 sistence, which, while it continues insoluble in water, has been thereby rendered more 
 readily absorbable and digestible (so to speak) by the roots of plants. I have there- 
 fore no doubt, that by the judicious application of these genuine guanos, mixed with 
 twice or thrice their weight of a marly or calcareous soil, to convert their phosphate of 
 ammonia into phosphate of lime and carbonate of ammonia, as also to dilute all their 
 ammoniacal compounds, — such crops will be produced, even on sterile lands, as the 
 farmer has never raised upon the most improved soil by the best ordinary manure. To 
 the West India planter, guano will prove the greatest boon, since it condenses in a 
 portable and inoffensive shape the means of restoring fertility to his exhausted cane 
 fields, a benefit it has long conferred on the poorest districts of Peru. 
 
 " I respectfully observe, that no analysis of guano hitherto made public at all ex- 
 hibits the value of the cargoes referred to above, while none gives the quantity of 
 ammonia dormant in the azotized animal matter of the bird's dung, which, called into 
 activity with the seeds in the soil, becomes the most valuable of its constituents, as a 
 source of perennial fertility. In the detailed account of my analyses of this complex 
 
130 
 
 GUANO. 
 
 excretion (now preparing for publication), all the above statements will be brought 
 within the scope of general comprehension. I shall also describe my ' ammonia gene- 
 rator,' based on the process invented in the laboratory of Professor Liehig, and also my 
 ' ammonia meter,' which, together, can detect and measure one-hundredth part of a 
 grain weight of absolute ammonia, whether potential or actual, in any sample of 
 guano. 
 
 " Meanwhile the following may be offered as the average result of my analyses of 
 genuine guano in reference to its agricultural value : — 
 
 " I. Azotized animal matter, including urate of ammonia, to- 
 gether capable of affording from 8 to 16 per cent, of 
 ammonia by slow decomposition in the soil - - 50 
 
 2. Water - - - - - 8 to 1 1 
 
 3. Phosphate of lime - - - 12 to 25 
 
 4. Phosphate of ammonia, sulphate of ammonia, ammonia- 
 
 phosphate of magnesia, together containing from 5 to 
 
 9 parts of ammonia - - - - -13 
 
 5. Siliceous sand - - - - - - 1 
 
 100 
 
 " Very moist guano has in general more actual and less potential ammonia than the 
 dry guano. 
 
 " Andrew Ure. 
 
 "London, 13. Charlotte Street, Bedford Square, 
 "February 14. 1843." 
 
 Oellacher's analysis of a brownish yellow guano is as follows : — 
 
 
 
 
 Ammonia. 
 
 1. 
 
 Urate of ammonia 
 
 - 12-20 
 
 1-06 
 
 2. 
 
 Oxalate of ammonia 
 
 - 17-73 
 
 6-50 
 
 3. 
 
 Oxalate of lime - - - 
 
 1 -30 
 
 
 4. 
 
 Phosphate of ammonia 
 
 6-90 
 
 1-79 
 
 5. 
 
 Phosphate of ammonia and magnesia 
 
 - 1 1 -63 
 
 1-68 
 
 6. 
 
 Phosphate of lime 
 
 - 20-16 
 
 
 7. 
 
 Muriate of ammonia 
 
 2-25 
 
 0-72 
 
 8. 
 
 Chloride of sodium (common salt) 
 
 - 0-40 
 
 
 9. 
 
 Carbonate of ammonia 
 
 - 0-80 
 
 0-23 
 
 10. 
 
 Carbonate of lime 
 
 1-65 
 
 
 11. 
 
 Sulphate of potash 
 
 4-00 
 
 
 12. 
 
 Sulphate of soda 
 
 4-92 
 
 
 13. 
 
 Humate of ammonia 
 
 1 -06 
 
 0-09 
 
 14. 
 
 Substance resembling wax 
 
 - 0-75 
 
 
 15. 
 
 Sand - 
 
 1-68 
 
 
 16. 
 
 Water (hygroscopic) 
 
 - 4-31 
 
 
 17. 
 
 Undefined organic matter 
 
 8-26 
 
 
 
 
 100-00 
 
 12-07 
 
 I am satisfied from its large proportion of oxalate of ammonia, that the sample thus 
 analyzed was by no means a fair or normal specimen of guano ; and it is in fact widely 
 different from all the fresh samples which have passed through my hands. It is 
 described as " Knobby, being mixed vrith light laminated crystalline portions, in white 
 grains, from the size of a pea to that of a pigeon's egg." Having some lumpy concre- 
 tions of a similar aspect in my possession, I submitted them to chemical examination. 
 
 G. 1000 grains being digested in boiling water and strained, afforded a nearly colourless 
 solution. This was concentrated till crystals of oxalate of ammonia appeared. It was 
 then acidulated with hydrochloric acid, to protect the phosphoric acid from preci- 
 pitation, and next treated carefully with solution of nitrate of lime equivalent to the 
 oxalic acid present. The oxalate of lime thus obtained being converted into carbonate 
 weighed 80*5 grains, corresponding to 100 of oxalate of ammonia, being 10 percent, 
 of the weight of the guano. 
 
 The liquor filtered from the oxalate was precipitated by nitrate of barytes, and 
 afforded 112 grains of sulphate of barytes = 38 sulphuric acid; and the last filtrate 
 being mixed with a given measure of ferric acetate, and the mixture supersaturated 
 with ammonia, yielded subphosphate of iron, equivalent to 5 per cent, of phosphoric 
 acid. I digested with heat other 500 grains of the same guano in a weak solution of 
 borax, filtered, acidulated the liquid, but obtained merely a trace of uric acid. It is 
 
GUMS. 
 
 131 
 
 clear therefore that the oxalate of ammonia had been formed in this guano at the 
 expense of the uric acid, and that its concreted state, and the crystalline nodules 
 disseminated through it were the result of transformation by moisture in a hot climate, 
 which had agglomerated it to a density of l - 75 ; whereas clean fresh guano, friable and 
 dry like the above, is seldom denser than 1-65. This guano contained only 3*23 of 
 ammonia; 65 of insoluble matter, 53 of earthy phosphates, 5 silica, 3 alkaline salts 
 (fixed), and 7 organic matter. 
 
 Oxalate of ammonia, being readily washed away, is a bad substitute for the urate 
 of ammonia, urea, and azotized animal matter, which it has replaced. Oellacher 
 could find no urea in the guano which he analyzed ; another proof of its dis- 
 integration. 
 
 Bartels' analysis of a brown-red guano is as follows : — 
 
 1. 
 
 Muriate of ammonia - 
 
 6-500 
 
 2. 
 
 Oxalate of ammonia - - - - 
 
 13-351 
 
 3. 
 
 Urate of ammonia - - - - 
 
 3-244 
 
 4. 
 
 Phosphate of ammonia - 
 
 6-450 
 
 5. 
 
 Substances resembling wax and resin 
 
 0-600 
 
 6. 
 
 Sulphate of potash - - - 
 
 4-277 
 
 7. 
 
 Sulphate of soda - 
 
 1-119 
 
 8. 
 
 Phosphate of soda - - 
 
 5 291 
 
 9. 
 
 Phosphate of lime - 
 
 9-940 
 
 10. 
 
 Phosphate of ammonia and magnesia 
 
 4-196 
 
 11. 
 
 Common salt - 
 
 o-ioo 
 
 12. 
 
 Oxalate of lime - - - - - 
 
 16-360 
 
 13. 
 
 Alumina - 
 
 0-104 
 
 14. 
 
 Sand insoluble in nitric acid, and iron - 
 
 5-800 
 
 15. 
 
 Loss (water and volatile ammonia and undefined 
 
 
 
 organic matter) - - - - 
 
 22-718 
 
 
 
 100-000 
 
 Voelckel, in his analysis of guano, states 7 per cent, of oxalate of lime — a result 
 quite at variance with all my experience — for I have never found so much as 2 per 
 cent, of carbonate of lime in the washed and gently ignited insoluble matter; whereas, 
 according to Bartels and Voelckel, from 10 to 5 per cent, of carbonate should be ob- 
 tained, as the equivalents of the proportions of the oxalate assigned by them. 
 
 All these analyses are defective moreover in not showing the total quantity of 
 ammonia which the guano is capable of giving out in the soil ; and since it appears 
 that the freshest guano abounds most in what I have called potential ammonia, it must 
 possess, of consequence, the greatest fertilizing virtue. 
 
 A sample of decayed dark-brown moist guano from Chile, being examined as 
 above described, for oxalate of ammonia, was found to contain none whatever ; and it 
 contained less than 1 per cent, of uric acid. 
 
 H. An article offered to the public, by advertisement, as Peruvian guano, was lately 
 sent to me for analysis. I found it to be a spurious composition ; it consisted of — 
 
 1. Common salt - - - - 32-0 
 
 2. Common siliceous sand - - - i8 0 
 
 3. Sulphate of iron or copperas - - - 5 2 
 
 4. Phosphate of lime - - - 4 '0, with 
 
 5. Organic matter from bad guano, &c. (to give it smell) 23 -3 
 
 6. Moisture - - - - -7 5 
 
 100 0 
 
 Genuine guano, when burned upon a red hot shovel, leaves a white ash of phos- 
 phate of lime and magnesia; whereas this factitious substance left a black fused 
 mass of sea salt, copperas, and sand. The specific gravity of good fresh guano is 
 seldom more than 1 -66, water being 100 ; whereas that of the said substance was so high 
 as 2-1 7 ; produced by the salt, sand, and copperas. 
 
 GUMS. Under the generic name Gum several substances have been classed, which 
 differ essentially, though they possess the following properties in common ; viz. form- 
 ing a thick mucilaginous liquid with water, and being precipitable from that solution 
 by alcohol. Properly speaking, we should style gums only such substances as are trans- 
 formed into mucic acid by nitric acid; of which bodies there are three : 1. Arabine, 
 which constitutes almost the whole of gum arabic ; 2. Bassorine, which forms the chief 
 part of gum tragacanth ; and 3- Cerasine, which occurs in cherry-tree gum, and is 
 convertible into gum arabic by hot water. 
 
 1. Gum arabic, in its ordinary state, contains 17 per cent, of water, separable from it 
 by a heat of '212° F. 
 
 S 2 
 
132 
 
 HATS 
 
 2. Cherry-tree gum consists of 52 per cent, of arabine, and 35 of a peculiar gum, 
 which has been called Cerasine. This latter substance is convertible into grape sugar 
 by boiling it with very dilute sulphuric acid. 
 
 GUNPOWDER, ANALYSIS OF. M. Bolley dissolves out the sulphur from 
 charcoal in gunpowder (previously freed from its nitre by water), by digesting it, at a 
 boiling heat for 2 hours, with the solution of 20 times its weight of sulphite of soda, 
 which is thereby converted into hyposulphite. To the mixture water must be added, 
 as it is wasted by the boiling. If the residuum be heated on platinum foil, it will ex- 
 hale sulphur, if this had not been all removed by the sulphurous salt. 
 
 H. 
 
 HArR CLOTH. See Weaving. 
 
 HATS. The body of a beaver hat is made of fine wool and coarse fur mixed and 
 felted together, then stiffened and shaped ; the covering consists of a coat of beaver fur 
 felted upon the body. Cheap hats have their bodies made of coarse wool, and their 
 coverings of coarse fur or fine wool. The body or foundation of a good beaver hat, is 
 at present made of 8 parts of rabbit's fur, 3 parts of Saxony wool, and 1 part of lama, 
 vicunia, or red wool. About two ounces and a half of the above mixture are sufficient 
 for one hat, and these are placed in the hands of the bower ; his tool is a bow or bent 
 ashen staff, from 5 to 7 feet long, having a strong catgut string stretched over a bridge 
 at each end, and suspended at its middle by a cord to the ceiling, so as to hang nearly 
 level with the work-bench, and a small space above it. The wool and coarser fur are 
 laid in their somewhat matted state upon this bench, when the bower, grasping the bent 
 rod with his left hand, and by means of a small wooden catch plucking the string with his 
 right, makes it vibrate smartly against the fibrous substances, so as to disentangle them, 
 toss them up in the air, and curiously arrange themselves in a pretty uniform layer or 
 fleece. A skilful bower is a valuable workman. The bowed materials of one hat are 
 spread out and divided into two portions, each of which is compressed first with a light 
 wicker frame, and next under a piece of oil cloth or leather, called a hardening skin, 
 till by pressing the hands backwards and forwards all over the skin, the filaments are 
 linked together by their serrations into a somewhat coherent fleece of a triangular shape. 
 The two halves or " bats" are then formed into a cap ; one of them is covered in its 
 middle with a 3-cornered piece of paper, smaller than itself, so that its edges may be 
 folded over the paper, and by overlapping each other a little, form a complete envelope 
 to the paper ; the junctions are then partially felted together by rubbing them hard, 
 care being taken to keep the base of the triangle open by means of the paper ; the se- 
 cond bat being made to enclose the first by a similar process of folding and friction. 
 This double cap, with its enclosed sheet of paper, is next rolled up in a damp cloth and 
 kneaded with the hands in every direction, during which it is unfolded and creased up 
 again in different forms, whereby the two layers get thoroughly incorporated into one 
 body ; thus, on withdrawing the paper, a hollow cone is obtained. The above opera- 
 tions have been partially described in the body of the Dictionary, and the remaining 
 steps in making a hat are there sufficiently detailed. 
 
 In a great hat factory women are employed, at respectable wages, in plucking the 
 beaver skins, cropping off the fur, sorting various qualities of wool, plucking and cutting 
 rabbits' fur, shearing the nap of the blocked hat, picking out unseemly filaments of fur, 
 and in trimming the hats ; that is, lining and binding them. 
 
 The annual value of the hats manufactured at present in the United Kingdom is 
 estimated at 3,000,000/. sterling. The quantity exported in 1840, was 22,522 dozens, 
 valued at 81,583/. 
 
 With regard to the stiffening of hats, I have been furnished by a skilful operator with 
 the following valuable information : — " All the solutions of gums which I have hitherto 
 seen prepared by hatters, have not been perfect, but, in a certain degree, a mixture, more 
 or less, of the gums, which are merely suspended, owing to the consistency of the com- 
 position. When this is thinned by the addition of spirit, and allowed to stand, it lets 
 fall a curdy looking sediment, and to this circumstance may be ascribed the frequent 
 breaking of hats. My method of proceeding is, first to dissolve the gums by agitation 
 in twice the due quantity of spirits, whether of wood or wine, and then, after complete 
 solution, draw off one half the spirit in a still, so as to bring the stiffening to a proper 
 consistency. No sediment subsequently appears on diluting this solution, however 
 much it may be done. 
 
 " Both the spirit and alkali stiffenings for hats made by the following two recipes, 
 have been tried by some of the first houses in the trade, and have been much ap- 
 proved of: — 
 
HOPS. 
 
 133 
 
 Spirit Stiffening. 
 
 7 pounds of fine orange shellac. 
 " 2 pounds of gum sandarac. 
 
 4 ounces of gum mastic. 
 Half a pound of amber rosin. 
 1 pint of solution of copal. 
 1 gallon of spirit of wine or wood naphtha. 
 
 " The shellac, sandarac, mastic, and rosin, are dissolved in the spirit, and the solution 
 of copal is added last. 
 
 Alkali Stiffening. 
 
 7 pounds of common block shellac. 
 
 1 pound of amber rosin. 
 
 4 ounces of gum thus. 
 
 4 ounces of gum mastic. 
 
 6 ounces of borax. 
 
 Half a pint of solution of copal. 
 
 " The borax is first dissolved in a little warm water (say 1 gallon) ; this alkaline liquor 
 is now put into a copper pan (heated by steam), together with the shellac, rosin, thus, and 
 mastic, and allowed to boil for some time, more warm water being added occasionally 
 until it is of a proper consistence; this may be known by pouring a little on a cold slab 
 somewhat inclined, and if the liquor runs off at the lower end, it is sufficiently fluid ; if, 
 on the contrary, it sets before it reaches the bottom, it requires more water. When the 
 whole of the gums seem dissolved, half a pint of wood naphtha must be introduced, and 
 the solution of copal ; then the liquor must be passed through a fine sieve, and it will 
 be perfectly clear and ready for use. This stiffening is used hot. The hat bodies, 
 before they are stiffened, should be steeped in a weak solution of soda in water, to 
 destroy any acid that may have been left in them (as sulphuric acid is used in the mak- 
 ing of the bodies). If this is not attended to, should the hat body contain any acid 
 when it is dipped into the stiffening, the alkali is neutralized, and the gums consequently 
 precipitated. After the body has been steeped in the alkaline solution, it must be per- 
 fectly dried in the stove before the stiffening is applied ; when stiffened and stoved it 
 must be steeped all night in water, to which a small quantity of sulphuric acid has been 
 added ; this sets the stiffening in the hat body, and finishes the process. A good work- 
 man will stiffen 15 or 16 dozen hats a day. If the proof is required cheaper, more 
 shellac and rosin must be introduced." 
 
 HIDES, untanned ; buffalo, bull, cow, ox, or horse. Imported in 1840, 352,867 ; re- 
 tained for consumption, 302,789. Rates of duty : from west coast of Africa, not exceeding 
 14 pounds, 2s. 4d. ; from British possessions, dry, 2s., wet, Is. 2c?. ; from other places, 
 dry, 4s. 8c?., wet, 2s. Ad. Net revenue, 40,139/. in 1840, and 45,328/. in 1839. In 
 1839, 16,557 pounds of tanned hides were imported for home consumption, and in 1840 
 only 5,822 : at the rate from foreign parts of 6d. per pound, but if cut and trimmed, 
 9d. ; from British possessions 3d. , if cut and trimmed 4±d. per pound. 
 
 HOPS. 
 
 Annual Amount of Hop Duty, 
 
 Yrs. 
 
 Amount. 
 
 Yrs. 
 
 Amount. 
 
 Yrs. 
 
 Amount. 
 
 Yrs. 
 
 Amount. 
 
 Yrs. 
 
 Amount. 
 
 Yrs. 
 
 Amount. 
 
 1711 
 
 £43,437 
 
 1733 
 
 .£70,215 
 
 1755 
 
 £82,157 
 
 1777 
 
 £43,581 
 
 1799 
 
 £73,279 
 
 1821 
 
 £154,609 
 
 1712 
 
 30,278 
 
 1734 
 
 37,716 
 
 1756 
 
 48,106 
 
 1778 
 
 159,891 
 
 1800 
 
 72,928 
 
 1822 
 
 203,724 
 
 1713 
 
 23,018 
 
 1735 
 
 42,745 
 
 1757 
 
 69,713 
 
 1779 
 
 55,800 
 
 1801 
 
 241,227 
 
 1823 
 
 26,058 
 
 1714 
 
 14,457 
 
 1736 
 
 46,482 
 
 1758 
 
 72,896 
 
 1780 
 
 122,724 
 
 1802 
 
 15,463 
 
 1824 
 
 148,832 
 
 1715 
 
 44,975 
 
 1737 
 
 56,492 
 
 1759 
 
 42,115 
 
 1781 
 
 120,218 
 
 1803 
 
 199,305 
 
 1825 
 
 24,317 
 
 1716 
 
 20,354 
 
 1738 
 
 86,575 
 
 1760 
 
 117,992 
 
 1782 
 
 14,895 
 
 1804 
 
 177,617 
 
 1826 
 
 269,331 
 
 1717 
 
 54,669 
 
 1739 
 
 70,742 
 
 1761 
 
 79,776 
 
 1783 
 
 75,716 
 
 1805 
 
 32,904 
 
 1827 
 
 140,848 
 
 1718 
 
 15,005 
 
 1740 
 
 37,875 
 
 1762 
 
 79,295 
 
 1784 
 
 94,359 
 
 1806 
 
 153,102 
 
 1828 
 
 172,027 
 
 1719 
 
 90,317 
 
 1741 
 
 65,222 
 
 1763 
 
 88,315 
 
 1785 
 
 112,684 
 
 1807 
 
 100,071 
 
 1829 
 
 38,398 
 
 1720 
 
 38,169 
 
 1742 
 
 45,550 
 
 1764 
 
 17,178 
 
 1786 
 
 95,973 
 
 1808 
 
 251,089 
 
 1830 
 
 88,047 
 
 1721 
 
 61,362 
 
 1743 
 
 61,072 
 
 1765 
 
 73,778 
 
 1787 
 
 42,227 
 
 1809 
 
 63,452 
 
 1831 
 
 174,864 
 
 1722 
 
 49.443 
 
 1744 
 
 46,708 
 
 1766 
 
 116,445 
 
 1788 
 
 143,168 
 
 1810 
 
 73,514 
 
 1832 
 
 139,018 
 
 1723 
 
 30,279 
 
 1745 
 
 34,635 
 
 1767 
 
 25,997 
 
 1789 
 
 104,063 
 
 1811 
 
 157,025 
 
 1333 
 
 156,905 
 
 1724 
 
 61,271 
 
 1746 
 
 91,879 
 
 1768 
 
 114,002 
 
 1790 
 
 106,841 
 
 1812 
 
 30,633 
 
 1834 
 
 189,713 
 
 1725 
 
 6,526 
 
 1747 
 
 62,993 
 
 1769 
 
 16,201 
 
 1791 
 
 90,059 
 
 1813 
 
 131,482 
 
 1835 
 
 235,207 
 
 1726 
 
 80,031 
 
 1048 
 
 87,155 
 
 1770 
 
 101,131 
 
 1792 
 
 162,112 
 
 1814 
 
 140,202 
 
 1836 
 
 200,332 
 
 1727 
 
 69,409 
 
 1749 
 
 36,805 
 
 1771 
 
 33,143 
 
 1793 
 
 22,619 
 
 1815 
 
 123,878 
 
 1837 
 1838 
 
 178,578 
 
 1728 
 
 41,494 
 
 1750 
 
 72,138 
 
 1772 
 
 102,650 
 
 1794 
 
 203,063 
 
 1816 
 
 46,302 
 
 171,556 
 
 1729 
 
 48,441 
 
 1751 
 
 73,954 
 
 1773 
 
 45,847 
 
 1795 
 
 82,342 
 
 1817 
 
 66,522 
 
 1839 
 
 205,537 
 
 1730 
 
 44,419 
 
 1752 
 
 82,163 
 
 1774 
 
 138,887 
 
 1796 
 
 75,223 
 
 1818 
 
 199,465 
 
 1840 
 
 34,091 
 
 1731 
 
 22,600 
 
 1753 
 
 91,214 
 
 1775 
 
 41,597 
 
 1797 
 
 157,458 
 
 1819 
 
 242,476 
 
 1841 
 
 146,159 
 
 1732 
 
 35,135 
 
 1754 
 
 102,012 
 
 1776 
 
 125,691 
 
 1798 
 
 56,032 
 
 1820 
 
 138,330 
 
 1842 
 
 169,776 
 
134 ILLUMINATION, COST OF. 
 
 Number of Acres under the Cultivation of Hops in England. 
 
 1807 
 
 38,218 
 
 1813 
 
 39,521 
 
 1819 
 
 51,014 
 
 1825 
 
 46,718 
 
 1831 
 
 47,129 
 
 1837 
 
 56,323 
 
 1808 
 
 38,430 
 
 1814 
 
 40,571 
 
 1820 
 
 50,148 
 
 1826 
 
 50,471 
 
 1832 
 
 47,101 
 
 1838 
 
 55,045 
 
 1809 
 
 38,357 
 
 1815 
 
 42,150 
 
 1821 
 
 45,62 
 
 1827 
 
 49,485 
 
 1833 
 
 49,187 
 
 1839 
 
 52,305 
 
 1810 
 
 38,265 
 
 1816 
 
 41,219 
 
 1822 
 
 43,706 
 
 1828 
 
 48,365 
 
 1834 
 
 51,273 
 
 1840 
 
 44,805 
 
 1811 
 
 38,401 
 
 1817 
 
 46.493 
 
 1823 
 
 41,458 
 
 J 829 
 
 46,135 
 
 1835 
 
 53,816 
 
 1841 
 
 45,769 
 
 1812 
 
 38,700 
 
 1818 
 
 48,593 
 
 1824 
 
 43,419 
 
 1830 
 
 46,726 
 
 1836 
 
 55,422 
 
 1842 
 
 
 Hop Duties of particular Districts. 
 
 Rochester 
 Canterbury 
 
 Kent 
 
 Sussex - 
 Worcester 
 Farnham 
 North Clays 
 Essex - 
 Sundries - 
 
 1839. 
 
 1840. 
 
 1841. 
 
 1842. 
 
 60,802 16 6 
 50,649 3 0 
 
 23,256 19 8 
 5,757 0 4 
 
 51,490 3 8 
 33,900 14 10 
 
 58,812 4 7 
 31,019 13 5 
 
 111,451 19 6 
 65,026 19 7 
 16,639 16 4 
 7,730 7 2 
 2,005 13 10 
 1,624 5 9 
 1,058 11 5 
 
 29,014 0 0 
 3,080 12 9 
 239 19 0 
 1,643 18 7 
 57 4 1 
 35 17 1 
 20 4 8 
 
 85,150 18 6 
 38,086 13 10 
 12,076 19 8 
 7,702 10 2 
 1,159 7 10 
 977 3 0 
 705 8 7 
 
 90,731 18 0 
 43,561 10 0 
 19,825 2 11 
 11,678 18 4 
 1,724 2 7 
 2,050 19 11 
 203 U 3 
 
 
 .£•205,538 12 7 
 
 34,091 17 2 
 
 146,159 1 7 
 
 169,776 6 0 
 
 HORN. Mr. J. James has contrived a method of opening up the horns of cattle, by 
 which he avoids the risk of scorching or frizzling, which is apt to happen in heating 
 them over an open tire. He takes a solid block of iron pierced with a conical hole, 
 which is fitted with a conical iron plug, heats them in a stove to the temperature of 
 melting lead, and having previously cut up the horn lengthwise on one side with a saw, 
 he inserts its narrow end into the hole, and drives the plug into it with a mallet. By 
 the heat of the irons, the horn gets so softened in the course of about a minute, as to 
 bear flatting out in the usual way. 
 
 HYPOSULPHITE OF SODA. This salt, so extensively used in the practice 
 of Daguerreotyping, may be easily prepared in quantities by the following process : — 
 Mix one pound of finely pulverised ignited carbonate of soda with ten ounces of 
 flowers of sulphur, and heat the mixture slowly in a porcelain dish till the sulphur 
 melts. Stir the fused mass, so as to expose all its parts freely to the atmosphere, 
 whereby it passes from the state of a sulphuret, by the absorption of atmospherical 
 oxygen, into that of a sulphite, with the phenomenon of very slight incandescence. 
 Dissolve in water, filter the solution, and boil it immediately along with flowers of 
 sulphur. The filtered concentrated saline liquid will afford, on cooling, a large 
 quantity of pure and beautiful crystals of hyposulphite of soda. 
 
 I. 
 
 ILLUMINATION, COST OF. The production, diffusion, and economy of light, 
 are subjects of the highest interest both to men of science and men of the world; 
 leading the former to contemplate many of the most beautiful phenomena of Physics 
 and Chemistry, while they provide the latter with the artificial illumination so indis- 
 pensable to the business and pleasures of modern society. The great cost of light from 
 wax, spermaceti, and even stearic candles, as also the nuisance of the light from tallow 
 ones, have led to the invention of an endless variety of lamps, of which the best hitherto 
 known is undoubtedly the mechanical or Carcel lamp, so generally used by the opulent 
 families in Paris. In this lamp the oil is raised through tubes by clock-work, so as 
 continually to overflow at the bottom of the burning wick ; thus keeping it thoroughly 
 soaked, while the excess of the oil drops back into the cistern below. I have possessed 
 for several years an excellent lamp of this description, which performs most satisfactorily ; 
 but it can hardly be trusted in the hands of a servant ; and when it gets at all deranged, 
 it must be sent to its constructor in Paris to be repaired. The light of this lamp, when 
 furnished with an appropriate tall glass chimney, is very brilliant, though not perfectly 
 uniform ; since it fluctuates a little, but always perceptibly to a nice observer, with the 
 alternating action of the pump- work ; becoming dimmer after every successive jet of 
 oil, and brighter just before its return. The flame, moreover, always flickers more or 
 less, owing to the powerful draught, and rectangular reverberatory shoulder of the 
 chimney. The mechanical lamp is, however, remarkable for continuing to burn, not 
 only with unabated but with increasing splendour for seven or eight hours ; the vivacity 
 of the combustion increasing evidently with the increased temperature and fluency of 
 
ILLUMINATION, COST OF. 
 
 135 
 
 the oil, which, by its ceaseless circulation through the ignited wick, gets eventually 
 pretty warm. In the comparative experiments made upon different lights by the 
 Parisian philosophers, the mechanical lamp is commonly taken as the standard. I do 
 not think it entitled to this pre-eminence: for it may be made to emit very different 
 quantities of light, according to differences in the nature and supply of the oil, as well 
 as variations in the form and position of the chimney. Besides, such lamps are too 
 rare in this country to be selected as standards of illumination. 
 
 After comparing lights of many kinds, I find every reason to conclude that a large 
 wax candle of three to the pound, either long or short, that is, either 12 or 15 inches 
 in length, as manufactured by one of the great wax-chandlers of London, and furnished 
 with a wick containing 27 or 28 threads of the best Turkey cotton, is capable of fur- 
 nishing a most uniform, or nearly invariable standard of illumination. It affords one- 
 tenth of the light emitted by one of the Argand lamps of the Trinity House, and one- 
 eleventh of the light of my mechanical lamp, when each lamp is made to burn with its 
 maximum flame, short of smoking. 
 
 The great obstacle to the combustion of lamps, lies in the viscidity, and consequent 
 sluggish supply of oil, to the wicks ; an obstacle nearly insuperable with lamps of the 
 common construction during the winter months. The relative viscidity, or relative 
 fluency of different liquids at the same temperature, and of the same liquid at different 
 temperatures, has not, I believe, been hitherto made the subject of accurate researches. 
 I was, therefore, induced to make the following experiments with this view. 
 
 Into a hemispherical cup of platinum, resting on the ring of a chemical stand, I 
 introduced 2000 water-grain measures of the liquid whose viscidity was to be measured, 
 and ran it off through a glass syphon, i of an inch in the bore, having the outer leg 3^ 
 inches, and the inner leg 3 inches long. The time of efflux became the measure of the 
 viscidity ; and of two liquids, if the specific gravity, and consequent pressure upon the 
 syphon, were the same, that time would indicate exactly the relative viscidity of the two 
 liquids. Thus, oil of turpentine and sperm oil have each very nearly the same density ; 
 the former being, as sold in the shops, =0.876, and the latter from 0 876 to 0-880, 
 when pure and genuine. Now I found that 2000 grain-measures of oil of turpentine 
 ran off through the small syphon in 95 seconds, while that quantity of sperm oil took 
 2700 seconds, being in the ratio of 1 to 28^ ; so that the fluency of oil of turpentine is 
 281 times greater than that of sperm oil. Pyroxilic spirit, commonly called naphtha, 
 and alcohol, each of specific gravity 0.825, were found to run off respectively in 80 and 
 120 seconds; showing that the former was 50 per cent, more fluent than the latter. 
 Sperm oil, when heated to 265° Fahr., runs off in 300 seconds, or one-ninth of the time 
 it took when at the temperature of 64°. Southern whale oil, having a greater density 
 than the sperm oil, would flow off faster were it not more viscid. 
 
 2000 grain-measures of water at 60° run off through the said syphon in 75 seconds, 
 but when heated to 180°, they run off in 61. 
 
 Concentrated sulphuric acid, though possessing the great density of 1.840, yet flows 
 off very slowly at 64°, on account of its viscidity ; whence its name of oil of vitriol. 
 2000 grain-measures of it took 660 seconds to discharge. 
 
 Mr. Samuel Parker, long advantageously known to the public for his sinumbral and 
 pneumatic fountain lamps, as well as other inventions subservient to domestic comfort, 
 having obtained a patent for a new lamp, in which the oil is heated by a very simple 
 contrivance, in the cistern, to any desired degree, before arriving at the wick, I 
 instituted an extensive series of experiments to determine its value in the production 
 of light, and consumption of oil, compared to the value of other lamps, as well as 
 candles, in these respects. 
 
 In fig. 73. A, A, B, B, is a section of the cylinder which constitutes the cistern ; 
 the oil being contained between the inner and outer cylinders, and receiving heat from 
 the flame of the lamp which passes up through the inner cylinder, and is rever- 
 berated more or less against its sides by the top of the metal chimney, being notched 
 and bent back. D is a slide-valve which is opened to allow the oil to descend to the 
 wick, and is shut when the cistern is to be separated from the pipe of supply, at E, 
 for the purpose of recharging it with oil. The flame is modified, not by raising or 
 lowering the wick, as in common lamps, but by raising or lowering the bell-mouthed 
 glass chimney which rests at its bottom on three points, and is moved by means of 
 the rack-work mechanism F. The concentric cylindric space A, A, and B, B, contains 
 a pint imperial, and should be made entirely full before lighting the lamp ; so as 
 to leave no air in the* cistern, which, by its expansion with the heat, would inevit- 
 ably cause an overflow of the oil. 
 
 The following arrangement was adopted in these experiments for determining the 
 relative illumination of the different lights. Having trimmed, with every precaution, 
 my French mechanical lamp, and charged it with pure sperm oil, I placed it upon an 
 oblong table, at a distance of 10 feet from a wall, on which a white sheet of paper was 
 
136 ILLUMINATION, COST OF 
 
 stuck. One of Mr. Parker's hot-oil lamps, charged with a quantity of the same oil, 
 was placed upon the same table ; and each being made to burn with its maximum 
 
 brilliancy, short of smoking, the relative illumination of the two lamps was determined 
 by the well-known method of the comparison of shadows ; a wire a few inches long, 
 and of the thickness of a crow-quill, being found suitable for enabling the eye to esti- 
 mate very nicely the shade of the intercepted light. It was observed in numerous 
 trials, both by my own eyes and those of others, that when one of the lamps was 
 shifted half an inch nearer to or further from the paper screen, it caused a perceptible 
 difference in the tint of the shadow. Professor Wheatstone kindly enabled me to verify 
 the precision of the above method of shadows, by employing, in some of the experi- 
 ments, a photometer of his own invention, in which the relative brightness of the two 
 lights was determined by the relative brightness of the opposite sides of a revolving 
 silvered ball, illuminated by them. 
 
 1. The mechanical lamp was furnished with a glass chimney 1*5 inches in diameter 
 at the base, and 1 -2 at top ; the wide bottom part was 1 -8 inches long, and the narrow 
 upper part 8 inches. When placed at a distance of 10 feet from the wall its light there 
 may be estimated as the square of this number, or 100. In the first series of experi- 
 ments, when burning with its maximum flame, with occasional flickerings of smoke, 
 it emitted a light equal to that of 1 1 wax candles, and consumed 912 grains of oil per 
 hour. The sperm oil was quite pure, having a specific gravity of 0'874 compared to 
 water at 1000. In a subsequent series of experiments, when its light was less flickering, 
 and equal only to that of 10 wax candles, it consumed only 815 grains, or 0*1164 of a 
 lb. per hour. If we multiply this number into the price of the oil (8s. per gallon) 
 per lb. lid., the product 1 -2804c?. will represent the relative cost of this illumination, 
 estimated at 1 00. ' 
 
 2. The hot-oil lamp burns with a much steadier flame than the mechanical, which 
 must be ascribed in no small degree to the rounded slope of the bell-mouthed glass 
 chimney, whereby the air is brought progressively closer and closer into contact with 
 the outer surface of the flame, without being furiously dashed against it, as it is by the 
 rectangular shoulder of the common contracted chimney. When charged with sperm 
 oil, and made to burn with its maximum flame, this lamp required to be placed one 
 foot further from the screen than the mechanical lamp, in order that its shadow should 
 have the same depth of tint. Hence, its relative illumination was, in that case, as the 
 square of 1 1 to the square of 10; or as 121 to 100. Yet its consumption of oil was 
 
ILLUMINATION, COST OF. 
 
 137 
 
 only 696 grains, or somewhat less than 0-1 of a lb. per hour. Had its light been 
 reduced to 100, it would have consumed only 576 grains per hour, or 0*82 of a lb. If 
 we multiply this number by lid., the product 0*902c?. will represent the relative cost 
 of 100 of this illumination. 
 
 3. The hot-oil lamp being charged with the southern whale oil, of specific gravity 
 0*926, at 2s. 6d. per gallon, or 2>\d. per lb., when burning with its maximum flame, 
 required to be placed 9 feet and 1 inch from the screen to drop the same tint of shadow 
 upon it as the flames of the other two lamps did at 10 and 11 feet with the sperm oil. 
 The square of 9 feet and 1 inch = 82 is the relative illumination of the hot-oil lamp 
 with the southern whale oil. It consumed 780 grains, or 0*111 of a pound per hour; 
 but had it given 100 of light it would have consumed 911 grains, or 0*130 of a pound, 
 which number being multiplied by its price ?>\d., the product 0*487 5d. will represent 
 the relative cost of 1 00 of this light. 
 
 4. A hot-oil lamp charged with olive oil of specific gravity 0*914, at 5s. 6d. per 
 gallon, or 1\ per lb. when burning with its maximum flame, required to be placed at 
 9 feet 6 inches, to obtain the standard tint of shadow upon the screen. It consumed 
 760 grains per hour. The square of 9\ feet is 90^, which is the relative intensity of the 
 light of this lamp. Had it emitted a light =100, it would have consumed 840 
 grains, or 0*12 of a pound per hour — which number multiplied by the price per pound, 
 gives the product 0 9c?. as the relative cost of 100 of this light. 
 
 5. A hot-oil lamp charged with Price and Co.'s cocoa-nut oil (oleine), of specific 
 gravity 0*925, at 4s. 6d. per gallon, or 5\d. per lb., had to be placed 9 feet from the 
 screen, and consumed 1035 grains per hour. Had its light been 100 instead of 81 (9 2 ), 
 the consumption would have been 1277 grains, or 0*182 of a pound per hour ! which 
 number multiplied by its price per pound, the product 1*03 Id. will represent the cost 
 of 1 00 of this illumination. 
 
 6. In comparing the common French annular lamp in general use with the me- 
 chanical lamp, it was found to give about one-half the light, and to consume two-thirds 
 of the oil of the mechanical lamp. 
 
 7. Wax candles from some of the most eminent wax -chandlers of the metropolis 
 were next subjected to experiment ; and it is very remarkable that, whether they were 
 threes, fours, or sixes in the pound, each afforded very nearly the same quantity of 
 light, for each required to be placed at a distance of three feet from the screen to afford 
 a shadow of the same tint as that dropped from the mechanical lamp, estimated at 100. 
 The consumption of a genuine wax candle, in still air, is upon an average of many 
 experiments, 125 grains per hour, but as it affords only of the light of the 
 mechanical lamp, 11 times 125=1375 grains, or 0*1064 of a pound is the quantity 
 that would need to be consumed to. produce a light equal to that of the said lamp. 
 If we multiply that number by the price of the candles per lb. = 30c?. the product 
 = 5*8 92c?. is the cost of 100 of illumination by wax. A wax candle, three in the pound 
 (short), is one inch in diameter, 12 inches in length, and contains 27 or 28 threads, 
 each about ^ of an inch in diameter. But the quality of the wick depends upon the 
 capillarity of the cotton fibrils, which is said to be greatest in the Turkey cotton, and 
 hence the wicks for the best wax candles are always made with cotton yarn imported 
 from the Levant. A wax candle, three in the pound (long), is | of an inch in diameter, 
 1 5 inches long, and has 26 threads in its wick. A wax candle, six to the pound, is 
 9 inches long, § of an inch in diameter, and has 22 threads in its wick. The light of 
 this candle may be reckoned to be, at most, about ^ less than that of the threes in the 
 pound. A well-made short three burns with surprising regularity in still air, being at 
 the rate of an inch in an hour and a half, so that the whole candle will last 1 8 hours. 
 A long three will last as long, and a six about 9\ hours. Specific gravity of wax 
 = 0*960. 
 
 8. A spermaceti candle, three in the pound, is T 9 5 of an inch in diameter, 15 inches 
 long, and has a plaited wick, instead of the parallel threads of a wax candle. The 
 same candles four in the pound, are ^ of an inch in diameter, and 1 3± inches long. 
 Each gives very nearly the same quantity of light as the corresponding wax candles : 
 viz. of the light of the above mechanical lamp, and consumes 142 grains per hour. 
 Multiplying the last number by 11, the product, 1562 grains = 0*223 of a pound would 
 be the consumption of spermaceti requisite to give 100 of illumination. Multiplying 
 the last number by 24c?., the price of the candles per pound, the product 5*352c?. is the 
 relative cost of 100 of this illumination. 
 
 9. Stearic Acid candles, commonly called German wax, consume 168*5 grains, or 
 0.024 of a pound per hour, when emitting the same light as the standard wax candle. 
 Multiplying the latter number by 11, and by 16c?. (the price of the candles per lb.), 
 the product 4*224c?. will represent the relative cost of 100 of this illumination. 
 
 10. Tallow candles: moulds, short threes, 1 inch in diameter, and 12^ in length; 
 ditto long threes, 7 9 5 of an inch in diameter, and 15 in length ; ditto, long fours, T 8 g of 
 
 T 
 
138 
 
 ILLUMINATION, COST OF. 
 
 an inch in diameter, and 18| in length. Each of these candles burns with a most un- 
 certain light, which varies from -j^to-jL of the light of the mechanical lamp — the average 
 may be taken at ^. The threes consume each 144 grains, or 0*2 of a pound, per hour; 
 which number, multiplied by 14, and by 9d. (the price per pound,) gives the product 
 2*52</. for the relative cost of 100 of this illumination. 
 
 11. Palmer's spreading wick candles. Distance from the screen 3 feet 4 inches, with 
 a shadow equal to the standard. Consumption of tallow per hour 232-5 grains, or 
 0*0332 of a pound. The square of 3 feet 4 inches=ll*9 is the relative illumination 
 of this candle = 11-9 :: 0-3332 :: 100 : 0-28 x 10rf. = 1 1 -9 is the relative cost of this 
 illumination. 
 
 12. Cocoa-nut stearine candles consumed each 168 grains per hour, and emitted a 
 light equal to ^ of the standard flame. Multiplying 168 by 16, the product 30*88 
 grains, or 0*441 of a lb., is the quantity which would be consumed per hour to afford 
 a light equal to 100. And 0-441 multiplied by 10c?., the price per lb., gives the 
 product 4*441<7. as the cost of 100 of this illumination per hour. 
 
 1 3. A gas Argand London lamp, of 1 2 holes in a circle of f of an inch in diameter, 
 with a flame 3 inches long, afforded a light = 781 compared to the mechanical lamp : 
 and estimating the light of the said mechanical lamp as before, at 100, that of the 
 hot-oil lamp is 121, and that of the above gas flame 78-57, or in round numbers 80, 
 and the common French lamp in general use 50. 
 
 Collecting the preceding results, we shall have the following tabular view of the 
 cost per hour of an illumination equal to that of the mechanical lamp, reckoned 100, 
 or that of eleven wax candles, three to the pound. 
 
 Table of Cost per Hour of One Hundred of Illumination. 
 
 1. Parker's hot-oil lamp, with southern whale oil 
 
 2. Mechanical or Carcel lamp, with sperm oil 
 
 3. Parker's hot-oil lamp, with sperm oil - 
 
 4. Ditto ditto common olive oil 
 
 5. Ditto ditto cocoa-nut oleine or oil 
 
 6. French lamp in general use, with sperm oil 
 
 7. Wax candles - - - - 
 
 8. Spermaceti candles - - - - 
 
 9. German wax (Stearic acid) ditto 
 
 10. Palmer's spreading wick candles - 
 
 11. Tallow (mould) candles - - 
 
 12. Cocoa-nut stearine of Price and Co. 
 
 Since the hot-oil lamp affords sufficient light for reading, writing, sewing, &c. with 
 one-fifth of its maximum flame, it will burn at that rate for 10 hours at the cost of 
 about one penny, and it is hence well entitled to the inventor's designation, " The 
 Economic." 
 
 Sir D. Brewster, in his examination lately before the committee of the House of 
 Commons on lighting the house, stated, that the French light-house lamp of Fresnel 
 emitted a light equal to that of forty Argand flames : whereas, according to other 
 accounts, it gave much less light. With the view of settling this point, before being 
 examined by the said committee, I repaired to the Trinity House, and tried one of 
 the two original Fresnel lamps, which had been deposited there by that eminent French 
 engineer himself. This lamp consists of four concentric circular wicks, placed in one 
 horizontal plane ; the innermost wick being \ of an inch in diameter, and the outermost 
 3| inches. Being carefully trimmed, supplied with the best sperm oil, surmounted 
 with its great glass chimney, burning with its maximum flame, and placed at a distance 
 of 1 3 feet 3 inches from the screen, it let fall a shadow of the same tint as that let fall 
 by the flame of my mechanical lamp, placed at a distance of 4 feet 6 inches from the 
 screen. The squares of these two numbers are very nearly as S\ to 1 (175*5625 to 
 20-25); showing that the Fresnel lamp gives less than 9 times the light of my me- 
 chanical lamp, and about 9-6 times the light of one of the Trinity House Argand 
 lamps. The Fresnel lamp is exceedingly troublesome to manage, from the great 
 intensity of its heat, and the frequent fractures of its chimneys — two having been 
 broken in the course of my experiments at the Trinity House. 
 
 Mr. Goldsworthy Gurney, the ingenious inventor of the new light-house lamp, in 
 which a stream of oxygen gas is sent up through a small tube within the burning 
 circular wick of a small Argand lamp, having politely sent two of his lamps to my 
 house, along with a bag of oxygen gas, T made the following experiments, to ascertain 
 their illuminating powers compared to those of the mechanical lamp and wax candles. 
 
 His larger lamp has a wick § of an inch in diameter, but emits an oxygen flame of 
 only I of an inch. The flame is so much whiter than that of the best lamp or candle, 
 
 Pence. 
 
 Pence. 
 
 0-4875 or about hi. 
 
 1-2804 - 
 
 - n 
 
 0-902 - 
 
 - i 
 
 0-900 - 
 
 - i 
 
 1*031 - 
 
 - i 
 
 1 *7072 - 
 
 - if 
 
 5*892 - 
 
 - 6 
 
 5*352 - 
 
 - H 
 
 4*224 - 
 
 - H 
 
 2*800 - 
 
 - n 
 
 2*520 - 
 
 - H 
 
 4*41 
 
 - H 
 
IRON. 
 
 139 
 
 that it becomes difficult to determine, with ultimate precision, the comparative depths 
 of the shadows let fall by them. The mean of several trials showed that the above 
 Bude-light (as Mr. Gurney calls it, from the name of his residence in Cornwall,) has 
 an illuminating power of from 28 to 30 wax candles. His smaller lamp has a flame 
 \ of an inch in diameter, and a wick i of an inch. Its light is equal to that of from 
 18 to 20 wax candles. 
 
 The committee of the House of Commons on lighting it, having asked me what 
 was the relative vitiation of air by the breathing of men and the burning of candles, 
 I gave the following answer : — 
 
 Wax contains 81-75 parts of carbon in 100, which generate by combustion 300 parts 
 of carbonic acid gas. Now, since 125 grains of wax constitute the average consumption 
 of a candle per hour, these will generate 375 grains of carbonic acid ; equivalent in 
 volume to 800 cubic inches of gas. According to the most exact experiments on 
 respiration, a man of ordinary size discharges from his lungs 1632 cubic inches of 
 carbonic acid gas per hour, which is very nearly the double of the quantity produced 
 from the wax candle: Hence the combustion of two such candles vitiates the air 
 much the same as the breathing of one man. A tallow candle, three or four in the 
 pound, generates nearly the same quantity of carbonic acid as the wax candle ; for 
 though tallow contains only 79 per cent, of carbon, instead of 81*75, yet it consumes 
 so much faster, as thereby to compensate fully for this difference. 
 
 When a tallow candle of 6 to the lb. is not snuffed, it loses in intensity, in 30 
 minutes, 80 hundredths ; and in 39 minutes 86 hundredths, in which dim state it re- 
 mains stationary, yet still consuming nearly the same proportion of tallow. A wax 
 candle attains to its greatest intensity of light when its wick has reached the greatest 
 length, and begins to bend out of the flame. The reason of this difference is, that only 
 the lower part of the wick in the tallow candle is charged with the fat, so as to emit 
 luminiferous vapour, while the upper part remains dry ; whereas, in the wax candle, 
 the combustible substance being less fusible and volatile, allows a greater length of the 
 wick to be charged by capillary attraction, and of course to emit a longer train of 
 
 The following table contains, according to Peclet, the illuminating powers of dif- 
 ferent candles, and their consumption t>f material in an hour ; the light emitted by a 
 Cared Argand lamp, consuming 42 grammes ( = 42 x 1 5\ grains) in an hour, being 
 called 100: — 
 
 
 Intensity of Light. 
 
 Consumption per Hour. 
 
 Tallow Candles 6 in lb. 
 
 10-66 
 
 8-51 
 
 Stearine, or Pressed Tallow, 8 in Jb. - 
 
 8-74 
 
 7-51 
 
 .... - ■ 5 in lb. - 
 
 7-50 
 
 7-42 
 
 Wax Candles, 5 in lb. 
 
 13-61 
 
 8-71 
 
 Spermaceti, 5 in lb. - 
 
 14-40 
 
 8-92 
 
 Stearic Acid, commonly called Stea- 
 
 
 
 rine, 5 in lb. 
 
 14-40 
 
 9-33 
 
 The subjoined table shows the economical ratios of the candles, where the second 
 column gives the quantity of material in grammes which is requisite to produce as 
 much light as the Carcel lamp : — 
 
 
 Quantity of 
 
 Price per Kilo- 
 
 Cost of Light per 
 
 
 Material. 
 
 gramme. 
 
 Hour. 
 
 Tallow Candle, 6 per lb. - 
 
 70-35 
 
 1 f. 40 c. 
 
 9'8 c. 
 
 8 per lb. - 
 
 85-92 
 
 If. 40 c. 
 
 12-0 c. 
 
 Pressed Tallow, 5 per lb. - 
 
 98-93 
 
 2 f. 40 c. 
 
 23-'/ c. 
 
 Wax Candle, 5 per lb. 
 
 64-04 
 
 7f. 60 c. 
 
 48-6 c. 
 
 Spermaceti ditto, 5 per lb. 
 
 61-94 
 
 7f. 60 c. 
 
 47 -8 c. 
 
 Stearine ditto, 5 per lb. 
 
 65-24 
 
 6f. 
 
 37-1 c. 
 
 These results may be compared with mine given above. A kilogramme, or 1000 
 grammes = 15,440 grains = 2\ lbs, avoirdupois. 
 
 INDIGO. Imported for home consumption, in 1839, 2,704,396 pounds ; in 1840, 
 2,996,215 ; duty 3d. on West Indian, 4d. on East Indian. 
 
 INK. Mr. Stephen's patent blue ink is made by dissolving Prussian blue in a so- 
 lution of oxalic acid. 
 
 IRON. For certain new processes for making malleable iron, Mr. W. N. Clay has 
 obtained two successive patents. Under the first, of December, 1 837, he mixed bruised 
 hematite, with one fifth of its weight of clean carbonaceous matter in coarse powder, 
 
 T 2 
 
140 
 
 IRON. 
 
 and subjected the mixture in a Q shaped retort to a bright red heat for twelve or more 
 hours, till the ore be reduced to the metallic state, as is easily ascertained by applying 
 a file to one of the fragments. When discharged, the metal is to be transferred into a 
 balling or puddling furnace, along with about five per cent, of ground coke or anthra- 
 cite, and worked therein in the usual way. He also proposes to use a conical kiln, like 
 that for burning lime, instead of the retorts. 
 
 In his second patent, dated March, 1 840, Mr. Clay prescribes above 28 per cent, 
 (from 30 to 40) of carbonaceous matter to be mixed with the ground-iron ore, contain- 
 ing at least 45 per cent, of metal, which mixture is to be directly treated in a puddling 
 furnace. He also proposes to use a mixture of pig or scrap iron and ore, in equal 
 quantities. 
 
 The application of the waste gases (carbonic oxide chiefly) of the blast furnace to 
 the purpose of heating the "puddling or balling furnace, was made the subject of a 
 patent in June, 1841, by a foreigner not named. The process had been previously 
 practised in Germany, and is fully described in the Annates des Mines, about two years 
 ago. 
 
 In Jig. 74. the manner of conveying the waste carbonic oxide from a blast furnace is 
 shown, a, a, a, are openings leading into the vertical channels or passages b, and from 
 
 thence into the chamber c. There is a top to this 
 chamber, with openings corresponding to the pas- 
 sages b. These openings are closed with cast-iron 
 plates that can be taken off for the purpose of 
 clearing out the passages b, and the chamber c. 
 From the chamber c, the gas may be conducted in 
 any direction, and to a distance of several hundred 
 feet. 
 
 In some localities, and in cases where it is re- 
 quired to take the gas from a blast furnace in 
 operation, a metal cylinder, of a smaller diameter 
 than the top of the furnace, and of a depth equal to 
 its diameter, is suspended vertically within the top 
 of the blast furnace the whole of its length. The 
 space between the cylinder and the furnace at the 
 top or mouth is to be hermetically sealed, and the 
 furnace is to be charged through the cylinder, which 
 must be kept full of minerals and combustibles. 
 Thus the space between the cylinder and the interior 
 of the furnace remains vacant, but the gas may be 
 conducted out of that part laterally, if required. 
 The gases led off from the blast furnace may, if 
 need be, pass through heated pipes, as for the hot 
 blast. 
 
 Figs. 75. and 76. represent a refining furnace for iron, with the necessary apparatus 
 for working it with the gases, without the use of other fuel ; Jig. 75. being a vertical 
 section, and Jig. 76. a sectional plan view. 
 
 The gas from the blast furnace is brought into the chamber a a, and, passing through 
 an opening b b, it enters the furnace, c c are a series of blow-pipes, through which the 
 heated air is forced into the furnace. In the space between the part marked b and the 
 tubes c, the gas becomes mixed with the heated atmospherical air. 
 
 This combustible gas from the blast furnace, mixed with the heated air, produces an 
 intense heat in the furnace, adequate to the refining of iron. The warm air for burning 
 the gas is usually obtained from the blowing machine and hot blast pipes. 
 
 For giving a still greater heat, the air may be carried through the tube f, into the 
 iron chambers g g, or a system of pipes, whence it is led through the tube h, into the 
 semi-circular chamber i, and then through the small pipes c, c, c, into the furnace. 
 
 The metal to be refined is placed in the space d d, in a liquid state, if the arrange- 
 ment of the furnaces will admit of its being so taken from the blast furnace ;"if not, it 
 may be nearly melted by the waste heat in the chamber e e. In order to decarbonise 
 
IRON. 
 
 141 
 
 the metal, a quantity of warm air, from the pipe h, is conducted - through the pipe k, 
 which is divided into two nozzles or tuyeres 1 1, and blown upon the fluid metal in the 
 space dd. After having been thus exposed for an hour or two, it is run oft* through 
 the opening m, and will be found in a refined state. 
 
 Figs. 77. 78. show the application to a puddling furnace. The openings nn admit 
 a stream of cold water to flow through the cast-iron piece oo, to preserve it from injury 
 by the fire. 
 
 77 78 
 
 Fig. 79. is a welding furnace ; the interior dimensions and the casing of the hearth 
 being different, as well as the fire bridge, from those of the puddling furnace. The 
 pipes for conducting the gases are made of cast-iron, and must have at least a sectional 
 area of one foot for every furnace that is to be heated. 
 
 Figs. 80, 81, 82, 83, 84. show the application of this invention to the generation of 
 steam. A chimney is here employed only at the commencement of the operation. The 
 
 air is forced into the furnace by any sort of blowing machine, or in any other con- 
 venient way. The fuel is introduced into the fire-place, upon the grate n n, through 
 the door a, which can be closed. The fire-place must contain as much fuel as will last 
 for several hours. When the fire is first lighted, the combustion takes place in the 
 ordinary way, on opening the door d, and the slide-valve b, and carrying through them 
 a current of air by the chimney draught. This is continued till the steam-engine 
 furnace, or any working (power) engine is in operation, after which a blowing apparatus 
 is employed to force the air through the tube c, as shown in Jig. 8 1 . The openings d 
 and b are then closed ; the air forced in now passes through the flues f, f, f, placed 
 round and beneath the boiler. The air, on arriving at the point g, is divided, one 
 portion passes through the opening h, regulated by a valve, into the open space beneath 
 the grate nn, to assist in the slow combustion of the fuel. The other part of the air 
 passes through g, into h h, round the fire-place, in order to heat the air to an intense 
 degree. After the second portion of the air has passed into the chamber h h, it enters 
 another i i, thence through a series of blowpipes, or through o, into pp, beneath the 
 
142 
 
 IRON. 
 
 boiler. The burnt air goes off through pp into a small chimney, through the opening 
 b b, which is regulated by a valve. 
 IRON, Cast, Strength of. 
 
 In the following Table, each bar is reduced to exactly one inch square ; and the 
 transverse strength, which may be taken as a criterion of the value of each iron, is 
 obtained from a mean between the experiments upon it, given in the Memoirs ; — first 
 on bars 4 ft. 6 in. between the supports, and next on those of half the length, or 
 2 ft. 3 in. between the supports. All the other results are deduced from the 4 ft. 6 in. 
 bars. In all cases the weights were laid on the middle of the bar. 
 
 Table of Results obtained from Experiments on the Strength and other Properties of 
 Cast Iron, from the principal Iron Works in the United Kingdom. By Mr. Wra. 
 Fairbairn. 
 
 Names of Irons. 
 
 I 
 
 
 
 
 lbs. 
 be- 
 
 .££ 
 
 
 .5 t 
 
 }f Experirr 
 n each. 
 
 fic gravity, 
 
 of elasti 
 per squ 
 r stiffness. 
 
 weight in 
 4 ft. 6 in. 
 upports. 
 
 ■S.S .5 
 
 — K5tO v> 
 
 ,*fjj $j c 
 ol 
 
 %~ 
 
 .5 
 
 £ 
 
 deflection 
 in. bars, 
 fan inch. 
 
 the 4 ft. 6 
 
 resist impa 
 
 s 
 
 'C 
 
 "odulus 
 in lbs. 
 inch, o 
 
 reaking 
 of bars 
 tween s 
 
 reaking 
 of bars 
 duced t 
 tween s 
 
 lean bri 
 in 
 
 Itimate 
 4 ft. 6 
 parts o 
 
 awer of 
 bars to 
 
 
 
 
 n 
 
 « 
 
 
 £> 
 
 El, 
 
 4 
 
 7-122 
 
 172I1000| 567 
 
 595 
 
 5S1 
 
 1-747 
 
 992 
 
 2 
 
 7-251 
 
 2 '175650 537 
 
 
 
 537 
 
 1-09 
 
 589 
 
 5 
 
 7'30C 
 
 22733400 
 
 543 
 
 517 
 
 550 
 
 1-005 
 
 549 
 
 2 
 
 7-0 56 
 
 17873100 
 
 520 
 
 534 
 
 527 
 
 1-365 
 
 71o 
 
 
 7-1 109 
 
 168020(10 
 
 505 
 
 529 
 
 517 
 
 1-599 
 
 807 
 
 4 
 
 
 155 7 '1500 489 
 
 515 
 
 502 
 
 1-815 
 
 889 
 
 4 
 
 7-066 
 
 15165000 
 
 495 
 
 487 
 
 491 
 
 1-764 
 
 872 
 
 4 
 
 7-071 
 
 16490000 
 
 483 
 
 495 
 
 489 
 
 1-581 
 
 765 
 
 5 
 
 7-049 
 
 14607000 
 
 441 
 
 529 
 
 485 
 
 1-621 
 
 718 
 
 4 
 
 7-108 
 
 16501000 
 
 478 
 
 470 
 
 47 1 
 
 1-512 
 
 729 
 
 4 
 
 7 -o.) 5 
 
 11509500 
 
 462 
 
 483 
 
 472 
 
 1-852 
 
 8 ">5 
 
 5 
 
 7-079 
 
 15381200 
 
 463 
 
 
 463 
 
 1-55 
 
 721 
 
 5 
 
 7-017 
 
 14911666 
 
 466 
 
 453 
 
 4 59 
 
 1-748 
 
 S15 
 
 
 7-017 
 
 14852000 
 
 457 
 
 455 
 
 4 56 
 
 1-730 
 
 791 
 
 4 
 
 7-059 
 
 14307500 
 
 453 
 
 457 
 
 455 
 
 1-811 
 
 822 
 
 4 
 
 7-038 
 
 15193000 
 
 438 
 
 473 
 
 455 
 
 1-484 
 
 650 
 
 
 7-038 
 
 13959500 
 
 453 
 
 455 
 
 454 
 
 1-957 
 
 886 
 
 4 
 
 7-113 
 
 14003550 
 
 443 
 
 464 
 
 453 
 
 1-734 
 
 770 
 
 5 
 
 7-080 
 
 13815500 
 
 441 
 
 457 
 
 449 
 
 1-759 
 
 777 
 
 5 
 
 7-159 
 
 14281466 
 
 433 
 
 464 
 
 4 48 
 
 1-726 
 
 717 
 
 4 
 
 7-285 
 
 22907700 
 
 448 
 
 
 4 18 
 
 •790 
 
 555 
 
 5 
 
 7-017 
 
 13891000 
 
 427 
 
 467 
 
 447 
 
 1-557 
 
 998 
 
 5 
 
 7-031 
 
 13112666 
 
 460 
 
 434 
 
 4 17 
 
 1-825 
 
 841 
 
 
 7-028 
 
 15787666 
 
 444 
 
 
 4 14 
 
 1-414 
 
 629 
 
 5 
 
 7-094 
 
 16246966 
 
 444 
 
 443 
 
 4 15 
 
 1-336 
 
 593 
 
 4 
 
 7-087 
 
 16554000 
 
 456 
 
 430 
 
 143 
 
 1-469 
 
 671 
 
 5 
 
 7-038 
 
 15971500 
 
 440 
 
 444 
 
 4 4 2 
 
 1-887 
 
 850 
 
 5 
 
 7-007 
 
 13,845866 
 
 430 
 
 454 
 
 4 12 
 
 1-687 
 
 727 
 
 5 
 
 7-080 
 
 13156500 
 
 439 
 
 441 
 
 4 10 
 
 1-857 
 
 816 
 
 5 
 
 G-979 
 
 15391766 
 
 432 
 
 449 
 
 440 
 
 1-443 
 
 625 
 
 4 
 
 7-051 
 
 15852500 
 
 427 
 
 449 
 
 458 
 
 1-368 
 
 585 
 
 3 
 
 6-998 
 
 13730500 
 
 436 
 
 
 436 
 
 1-64 
 
 721 
 
 5 
 
 7-080 
 
 15452500 
 
 461 
 
 403 
 
 432 
 
 1-516 
 
 699 
 
 5 
 
 6-975 
 
 15280900 
 
 408 
 
 455 
 
 451 
 
 1-251 
 
 511 
 
 6 
 
 7-051 
 
 15241000 
 
 419 
 
 439 
 
 429 
 
 1-358 
 
 570 
 
 5 
 
 7-011 
 
 14953333 
 
 413 
 
 446 
 
 429 
 
 1-339 
 
 55 1 
 
 4 
 
 7-058 
 
 14211000 
 
 408 
 
 446 
 
 4 27 
 
 1-512 
 
 618 
 
 4 
 
 6-928 
 
 12586500 
 
 446 
 
 408 
 
 127 
 
 2-224 
 
 992 
 
 4 
 
 7-007 
 
 15012000 
 
 422 
 
 430 
 
 4 26 
 
 1-450 
 
 621 
 
 5 
 
 7-128 
 
 15510066 
 
 464 
 
 385 
 
 424 
 
 1-532 
 
 716 
 
 4 
 
 7-069 
 
 1 7056000 
 
 430 
 
 408 
 
 419 
 
 1-231 
 
 530 
 
 4 
 
 6-953 
 
 15294400 
 
 417 
 
 419 
 
 418 
 
 1-570 
 
 656 
 
 5 
 
 7-185 
 
 16156133 
 
 404 
 
 432 
 
 418 
 
 1-222 
 
 491 
 
 4 
 
 6-969 
 
 14522500 
 
 409 
 
 424 
 
 416 
 
 1-882 
 
 771 
 
 5 
 
 6-9.55 
 
 14301000 
 
 408 
 
 418 
 
 415 
 
 1-470 
 
 600 
 
 3 
 
 6-916 
 
 12259500 
 
 402 
 
 404 
 
 403 
 
 1-762 
 
 709 
 
 3 
 
 6-957 
 
 1 1 559333 
 
 392 
 
 
 5"2 
 
 1-890 
 
 742 
 
 4 
 
 6-H76 
 
 11974500 
 
 353 
 
 386 
 
 569 
 
 1-525 
 
 558 
 
 5 
 
 6-916 
 
 15341633 
 
 378 
 
 337 
 
 557 
 
 
 517 
 
 Quality. 
 
 Ponkey, No. 3'' Cold Blast - 
 Devon, No. 3. Hot Blast * - 
 Oldberry, No. 3. Hot Blast 
 Carron, No. 3. Hot Blast * 
 Beaufort, No. 3. Hot Blast 
 Butterley - 
 
 Bute, No. 1. Cold Blast » 
 Wind Mill End, No.2. ColdBlast 
 Old Park, No. 2. Cold Blast - 
 Beaufort, No. 2. Hot Blast 
 Low Moor, No. 2. Cold Blast - 
 BufTery, No. 1. Cold Blast* 
 Brimbo, No. 2. Cold Blast 
 Apedale, No. 2. Hot Blast - 
 Oldberry, No. 2. Cold Blast 
 Pentwyn, No. 2. - 
 Maesteg, No.2. - - - - 
 Muirkirk, No. 1. Cold Blast* - 
 Adelphi, No. 2. Cold Blast 
 Blania, No. 3. Cold Blast - 
 Devon, No. 3. Cold Blast* 
 Gartsherrie, No. 3. Hot Blast - 
 Frood, No.2. Cold Blast - 
 Lane End, No. 2. - - - 
 Carron, No. 3. Cold Blast * 
 Dundivan, No. 3. Cold Blast - 
 Maesteg (Marked Red) 
 Corbyns Hall, No. 2. 
 Pontypool, No. 2. 
 Wallbrook, No. 3. - - - 
 Milton, No. 3. Hot Blast - 
 Buffery, No. 1. Hot Blast* 
 Level, No. 1. Hot Blast - 
 Pant, No. 2. - 
 Level, No. 2. Hot Blast - - 
 W. S.S., No.2.- - - - 
 Eagle Foundry, No. 2. Hot Blast 
 Elsicar, No. 2. Cold Blast - 
 Varteg, No. 2. Hot Blast - 
 ColthSm, No. 1. Hot Blast 
 Carroll, No. 2. Cold Blast - 
 Muirkirk, No.l. Hot Blast* - 
 Bierley, No. 2. - 
 Coed-Talon, No. 2. Hot Btast* 
 Coed-Talon, No.2. Cold Blast* 
 Monkland, No. 2. Hot Blast - 
 Ley's Works, No. 1. Hot Blast 
 Milton, No. 1. Hot Blast - 
 Plaskynaston, No. 2. Hot Blast - 
 
 Whitish grey 
 White - 
 White - - 
 Whitish grey 
 Dullish grey 
 Dark grey - 
 Bluish grey 
 Dark grey - 
 >Grey - - . 
 Dull grey - 
 Dark grey - 
 Grey - - 
 Light grey - 
 Light grey - 
 Dark grey - 
 Bluish grey 
 Dark grey - 
 B.right grey 
 Light grey - 
 Bright grey 
 Light grey - 
 Light grey - 
 Light grey - 
 Dark grey - 
 Grey - - - 
 Dull grey - 
 Bluish grey 
 Grey . - 
 Dull blue - 
 Light grey - 
 Grey - - - 
 Dull grey - 
 Light grey - 
 Light grey - 
 Dull grey - 
 Light grey - 
 Bluish grey 
 Grey - - 
 Grey - - 
 Whitish grey 
 Grey - - - 
 Bluish grey 
 Dark grey - 
 Bright grey 
 Grey - - 
 Bluish grey 
 Bluish grey 
 Grey - - - 
 Light grey - 
 
 Hard. 
 
 Hard. 
 
 Hard. 
 
 Hard. 
 
 Hard. 
 
 Soft. 
 
 Soft. 
 
 Hard. 
 
 Soft. 
 
 Hard. 
 
 Soft. 
 
 Rather hard 
 Rather hard 
 Stiff. 
 
 Rather soft. 
 Hard. 
 
 Rather soft. 
 
 Fluid. 
 
 Soft. 
 
 Hard. 
 
 Hard. 
 
 Soft. 
 
 Open. 
 
 Soft. 
 
 Soft. 
 
 Rather soft. 
 
 Fluid. 
 
 Soft. 
 
 Rather soft. 
 Rather hard , 
 Rather hard, 
 Soft. 
 Soft. 
 
 Rathe r hard. 
 
 Soft 
 
 Soft 
 
 Soft 
 
 Soft 
 
 Har 
 
 Rather soft.' 
 
 Hard. 
 
 Soft. 
 
 Soft. 
 
 Soft. 
 
 Rather soft. 
 
 Soft. 
 
 Soft. 
 
 Soft&flui'l 
 Rather sof 
 
 Rule. — To find from the above table the breaking weight in rectangular bars, gene- 
 rally, calling b and d the breadth and depth in inches, and I the distance between the 
 
 . „ , . „ . 4-5xbd*S 
 supports in feet, and putting 4 5 for 4 ft. 6 in., we have j = breaking 
 
 weight in lbs., the value of S being taken from the table above. 
 
 For example : — What weight would be necessary to break a bar of Low Moor 
 
 iron, 2 inches broad, 3 inches deep, and 6 feet between the supports ? According to 
 
 the rule given above, we have 6 = 2 inches, d=3 inches, 7=6 feet, S = 472 from the 
 
 * ui ™ 4'5xbd*S 4-5 x 2 x32 x472 ' a iU . .. 
 
 table. Then = =6372 lhs., the breaking weight. 
 
 * The irons with asterisks are taken from the experiments on hot and cold blast iron, made by Mr. 
 
 Hodgkinson and myself for the British Association for the Advancement of Science See Seventh 
 
 Report, vol. vi. 
 
 t The modulus of elasticity was usually taken from the deflection caused by 112 lbs. on the 4 ft. G in. 
 bars. 
 
[RON. 
 
 143 
 
 IRON. Hot Blast. To the account of this interesting innovation in the smelting 
 of iron ores, given in the dictionary, I have now the pleasure of representing in 
 accurate plans, the complete system mounted at the Codner Park Works belonging to 
 William Jessop, Esq. For the drawings, from which the woodcuts are faithfully 
 copied, I am indebted to Mr. Joseph Glynn, F. R.S., the distinguished engineer of 
 the Butterley Iron Works. 
 
 Figs. 85, 86, 87. exhibit the apparatus of the hot blast in every requisite detail. 
 The smelting furnaces have now generally three tuveres, and three sets of air heating 
 
 furnaces. The figures show two sets built together ; the third set being detached on 
 account of peculiar local circumstances. The air enters the horizontal pipe A, in the 
 ground plan, fig. 85., on one side of the arched or syphon pipes, shown in upright 
 section in fig. 86., and passes through these pipes to the horizontal pipe, B, on the 
 other side ; whence it. proceeds to the blast furnace. These syphon pipes are flattened 
 laterally, their section being a parallelogram, to give more heating surface, and also 
 more depth of pipe (in the vertical plane), so as to make it stronger, and less liable to 
 bend by its own weight when softened by the red heat. This system of arched pipe 
 apparatus is set in a kind of oven, from which the flue is taken out at the top of it ; 
 but it thence again descends, before it reaches the chimney, entering it nearly at the 
 level of the fire grate (as with coal gas retorts). By this contrivance, the pipes are 
 kept in a bath of ignited air, and not exposed to the corroding influence of a current of 
 flame. The places and directions of these oven flues are plainly marked in the 
 drawing. 
 
144 
 
 IRON. 
 
 Fig. 87. is a plan of the blast furnace, drawn to a smaller scale than that of the 
 preceding figures. 
 
 The three sets of hot-blast apparatus, all communicate with one line of conducting 
 pipes, A, which leads to the furnace. Thus in case of repairs being required in one 
 set, the other two may be kept in full activity, capable of supplying abundance of hot 
 air to the blast, though of a somewhat lower temperature. See Smelting for con- 
 structions of different blast furnaces ; also Puddling. 
 
 During a visit which I have recently made to Mr. Jessop, at Butterley, I found 
 this eminent and very ingenious iron-master had made several improvements upon his 
 hot-blast arrangements, whereby he prevented the alteration of form to which the 
 arched pipes were subject at a high temperature, as also that he was about to employ 
 five tuyeres instead of three. For a drawing and explanation of his furnace-feeding 
 apparatus, see Smelting. 
 
LAMPS. 145 
 
 ISINGLASS. Imported for home consumption in 1839, 1,644 cwts. ; in 1840, 
 1,589 cwts. See Gelatin for excellent substitutes for isinglass in culinary operations. 
 Were beer brewed by the Bavarian plan of fermentation, it would require no isinglass 
 for fining it. 
 
 IVORY. Imported of elephant's teeth for home consumption in 1839 s 3,929 cwts. ; 
 in 1840, 4,491 cwts. Duty Is. 
 
 E. 
 
 KILLAS. The name given by the Cornish miners to clay slate, commonly of a 
 greenish colour, in which the richest deposits of copper and tin occur. 
 
 L. 
 
 LAC DYE. Imported for home consumption in 1839, 532,881 pounds; in 1840, 
 644,092 pounds ; 6s. per cwt. duty. 
 
 LACTIC ACID. See Fermentation. 
 
 LAMPS. The leading novelty under this title, is the construction of lamps for 
 burning spirits of turpentine, in the place of the fat oils which alone have been in use 
 from the most remote ages down to the present year. Two patents have recently been 
 obtained for these lamps, under the fantastic title of Camphine ; one by Mr. William 
 Young, and another by Messrs. Rayner and Carter, as the invention of a working 
 miner — Roberts. Having been employed by the proprietors of these patents to 
 examine the performances of their respective lamps, I here insert the two reports 
 drawn up by me on these occasions : — 
 
 " The Vesta Lamp, burning with its utmost brilliancy, without smoke, emits a 
 
 U 
 
146 
 
 LEAD. 
 
 light equal to very nearly twelve wax or sperm candles of three or four to the pound ; 
 and in so doing, it consumes exactly one imperial pint of spirits of turpentine (value 
 sixpence retail) in ten hours, hence the cost per hour for a light equal to ten such 
 candles is one halfpenny ; whereas that from wax candles would be nearly sixpence; 
 from spermaceti ditto, fivepence ; from stearine ditto, fourpence ; from Palmer's 
 spreading wick ditto, nearly threepence ; from tallow moulds 2\d. ; from sperm oil in 
 Carcel's Mechanical French Lamp, \\d. 
 
 " One peculiar advantage of the Vesta Lamp is the snowy whiteness of its light, which 
 is such as to display the more delicate colours of natural and artificial objects, flowers, 
 paintings, &c. in their true tints, instead of the degraded hues visible by the light of 
 candles and ordinary oil lamps. 
 
 " The size of the flame from which so much light is emitted in the Vesta Lamp, 
 is greatly smaller than that of oil or gas Argand flames of equal intensity ; a circum- 
 stance to be accounted for from the difference in chemical composition, between spirits 
 of turpentine and fat oils. The spirits consist entirely of carbon and hydrogen ; in the 
 proportion of 881 of the former element, and Hi of the latter, in 100 parts ; and they 
 consume 328 parts of oxygen ; whereas, sperm and other unctuous oils consist of 78 
 parts of carbon, 1 11 of hydrogen, and 101 of oxygen, in 100 parts ; and these consume 
 only 287.2 of oxygen, in being burnt; because the oxygen already present in the oil 
 neutralises 2.6 parts of the carbon and 0.4 of the hydrogen, thus leaving only 851 parts 
 of the combustible elements for the atmosphere to bum. For this reason, 871 parts by 
 weight of spirits of turpentine, will consume as much oxygen as 100 parts of sperm 
 oil ; and will afford, moreover, a more vivid light, because they contain no oxide, as 
 fat oils do, which serves to damp the combustion. In the spirits of turpentine, the 
 affinity of its elements for oxygen is entire, whereas in fat oil the affinity is partially 
 neutralized by the oxides it contains ; somewhat as the flame of spirits of wine is 
 weakened by their dilution with water. 
 
 " Among the many applications of science to the useful arts, for which the present 
 age is so honourably distinguished, few are more meritorious than the Camphine 
 Lamps, by which we can produce a snow-white flame from the cleanly, colourless 
 spirits of turpentine, — a pure combustible fluid, in place of the smeary rank oils 
 which contain a seventh part of incombustible matter. Being so rich in hydro-carbon, 
 the spirits require, peculiar artifices for complete consumption and the development of 
 their full power of yielding light without smoke or smell. This point of perfection 
 seems to be happily attained by the invention of the two parallel flat rings, in the 
 Paragon Lamp, a larger and smaller, forming a cone round the margin of the wick, 
 which cause a rapid reverberation of the air against the flame : thus consuming every 
 particle of volatilized vapour, and adding energy to the luminous undulations. Hence 
 the patent Paragon Lamp in full action emits a light equal to that of sixteen wax 
 candles, three to the pound, but of better quality, approaching in purity to that of the 
 sun-beam, — therefore capable of displaying natural and artificial objects in their true 
 colours. 
 
 " One imperial pint of rectified spirits of turpentine, value 6d. retail, will burn for 
 twelve hours in this lamp, affording all the time the illumination of eleven wax candles. 
 " The Paragon Camphine Lamp is attended with no danger in use. 
 " The Cost, as compared with other Lamps or Candles, is as follows : viz. — 
 
 PER HOUR. 
 
 Paragon Camphine Lamp (equal to 1 1 wax candles,) less than One Halfpenny. 
 I Wax Candles - - - - - 6\d. 
 
 Spermaceti ditto - - - - - 5\ 
 
 Adamantean Wax (Stearic Acid) - - - 4| 
 
 Palmer's Spread- Wick Candles - - - 3\ 
 
 Cocoa Nut Candles - - - - - 4| 
 
 Moulds (Tallow) - - - - - 2| 
 
 Carcel's Lamp, with Sperm Oil - - - - 2" 
 
 See Illumination, cost of, for a description of an excellent oil lamp. 
 
 LEAD. The total produce of the lead mines of Great Britain was estimated in 
 1822, at 31,900 tons, which were distributed as follows : — 
 
 Wales (Flintshire and Derbyshire) - - 7,500 tons. 
 
 Scotland - - - - 2,800 
 
 Cornwall and Devonshire - - 800 
 
 Shropshire - - - 800 
 
 Derbyshire - - - 1,000 
 
 Cumberland, Durham, and Yorkshire - - 19,000 
 
 31,900 
 
LEATHER. 
 
 147 
 
 And in the year 1835, the total produce was estimated, by Mr. John Taylor, at 
 46,112 tons; of which 19,626 were furnished by Northumberland, Durham, and 
 Cumberland; the mines of Mr. Beaumont alone, yielding 10,000. See Solder. 
 
 LEATHER. In the Franklin Institute for February 1843, Mr. Gideon Lee has 
 published some judicious observations on the process of tanning. He believes that 
 much of the original gelatine of the hides is never combined with the tannin, but is 
 wasted; for he thinks that 100 lbs. of perfectly dry hide, when cleansed from extra- 
 neous matter, should, on chemical principles, afford at least 180 lbs. of leather. The 
 usual preparation of the hide for tanning he believes to be a wasteful process. In the 
 liming and bating, or the unhairing and the cleansing, the general plan is first to steep 
 the hides in milk of lime for one, two, or three weeks, according to the weather and 
 texture of the skin, until the hair and epidermis be so loosened as to be readily removed 
 by rubbing down, by means of a knife, upon a beam or block. Another mode is to 
 suspend the hides in a close chamber heated slightly by a smouldering fire, till the 
 epidermis gets loosened by incipient putrefaction. A third process, called sweating, 
 used in Germany, consists in laying the hides in a pack or pile, covered with tan, to 
 promote fermentative heat, and to loosen the epidermis and hairs. These plans, espe- 
 cially the two latter, are apt to injure the quality of the hides. 
 
 The bate consists in steeping the haired hides in a solution of pigeon's dung, con- 
 taining, Mr. Lee says, muriate of ammonia, muriate of soda, &c. ; but most probably 
 phosphates of ammonia and lime, with urate of ammonia, and very fermentable animal 
 matter. The dry hides are often subjected first of all to the operation of the fulling- 
 stocks, which opens the pores, but at the same time prepares them for the action of the 
 liming and bate ; as also for the introduction of the tanning matter. When the 
 fulling is too violent, the leather is apt to be too limber and thin. Mr. Lee conceives 
 that the liming is injurious, by carrying off more or less of the gelatine and albumen 
 of the skin. High-limed leather is loose, weighs light, and wears out quickly. The 
 subsequent fermentation in the bating aggravates that evil. Another process has 
 therefore been adopted in New York, Maine, New Hampshire, and some parts of 
 Philadelphia, called, but incorrectly, cool sweating, which consists in suspending the 
 hides in a subterranean vault, in a temperature of 50° Fahr., kept perfectly damp, by 
 the trickling of cold spring water from points in the roof. The hides being first 
 soaked, are suspended in this vault from 6 to 12 days, when the hair is well loosened, 
 by the mere softening effect of moisture, without fermentation. 
 
 LEATHER, MOROCCO. (Maroquin, Fr. Saffian, Germ.) Morocco leather of 
 the finer quality is made from goat-skins tanned with sumach ; inferior morocco leather 
 from sheep skins. The goat skins as imported are covered with hair ; to remove which 
 they are soaked in water for a certain time, and they are then subjected to the operation 
 called breaking, which consists in scraping them clean and smooth on the flesh side, 
 and they are next steeped in lime pits (milk of lime) for several days, during which 
 period they are drawn out, with a hook, from time to time, laid on the side of the pit to 
 drain, and replunged alternately, adding occasionally a little lime, whereby they are 
 eventually deprived of their hair. When this has become sufficiently loose, theskinsare 
 taken out one by one, laid on convex beams, the work benches, which stand in an inclined 
 position, resting on a stool at their upper end, at a height convenient for the workman's 
 breast, who scrapes off the hair with a concave steel blade or knife, having a handle at 
 each end. When unhaired, the skins are once more soaked in milk of lime for a few 
 days, and then scraped on the flesh side to render it very even. For removing the 
 lime which obstructs their pores, and would impede the tanning process, as well as to 
 open these pores, the skins are steeped in a warm semi-putrid alkaline liquor, made 
 with pigeons' and hens' dung diffused in water. Probably some very weak acid, such as 
 fermented bran water, would answer as well, and not be so offensive to the workmen. 
 (In Germany the skins are first washed in a barrel by a revolving axle and discs. ) They 
 are again scraped, and then sewed into bags, the grain outermost, like bladders, leaving 
 a small orifice, into which the neck of a funnel is inserted, and through which is poured 
 a certain quantity of a strong infusion of the sumach ; and they are now rendered tight 
 round the orifices, after being filled out with air, like a blown bladder. A parcel of these 
 inflated skins are thrown into a very large tub, containing a weaker infusion of sumach, 
 where they are rolled about in the midst of the liquor, to cause the infusion within to 
 act upon their whole surface, as well as to expose their outsides uniformly to the tan- 
 ning action of the bath. After a while these bladder skins are taken out of the bath, 
 and piled over each other upon a wooden rack, whereby they undergo such pressure as 
 to force the enclosed infusion to penetrate through their pores, and to bring the tannin 
 of the sumach into intimate contact, and to form a chemical combination with the skin 
 fibres. The tanning is completed by a repetition of the process, of introducing some 
 infusion or decoction into them, blowing them up, and floating them with agitation in 
 the bath. In this way goat skins may be well tanned in the course of one day. 
 
 U 2 
 
148 
 
 LEATHER. 
 
 The bags are next undone by removing the sewing, the tanned skins are scraped as 
 before on the currier's bench, and hung up in the drying loft or shed ; they are said 
 now to be " in the crust." They are again moistened and smoothed with a rubbing 
 tool before being subjected to the dyeing operations, in which two skins are applied face 
 to face to confine the dye to one of their surfaces only, for the sake of economising the 
 dyeing materials which may be of several different colours. The dyed skins are grained 
 by being strongly rubbed with a ball of box wood, finely grooved on its surface. 
 
 Tawing of Skins. (Megisserie, Fr. ; Weissgerberei, Germ.). The kid, sheep, and 
 lamb skins, are cleaned as has been described under leather in the Dictionary. In some 
 factories they receive the tanning power of the submuriate of alumina (from a solution 
 of alum and common salt) in a large barrel-churn apparatus ; in which they are sub- 
 jected to violent agitation, and thereby take the aluming in the course of a few minutes. 
 In other cases, where the yolks of eggs are added to the above solution, the mixture, 
 with the skins, is put into a large tub, and the whole trampled strongly by the naked 
 feet of the operator, till the emulsion of the egg be forced into the pores of the skin. 
 The tawed skins, when dry, are " staked," that is stretched, scraped, and smoothed by 
 friction against the blunt edge of a semicircular knife, fixed to the top of a short beam 
 of wood set upright. The workman holding the extremities of the skin with both 
 hands, pulls it in all directions forcibly, but skilfully, against the smoothing " stake.' 
 
 In an entertaining article on tanning in the 11th vol. of the Penny Magazine, at 
 page 215., the following description is given of one of the great tawing establishments 
 of London. 
 
 " In the production of ' imitation ' kid leather, the skin of lambs is employed ; and 
 for this purpose lamb-skins are imported from the shores of the Mediterranean. They 
 are imported with the wool yet on them ; and as this wool is valuable, the leather 
 manufacturer removes this before the operations on the pelt commence. The wool is 
 of a quality that would be greatly injured by the contact of lime, and therefore a kind 
 of natural fermentation is brought about as a means of loosening the wool from the pelt. 
 At the Neckinger establishment of Messrs. Bevington and Co. Bermondsey, one of the 
 buildings presents, on the ground floor, a flight of stone steps, leading down to a range 
 of subterranean vaults or close rooms, into which the lamb- skins are introduced in a 
 wet state, after having been steeped in water, ' broken ' on the flesh side, and drained. 
 The temperature of these rooms is nearly the same all the year round, a result obtained 
 by having them excluded as much as possible from the variations of the external atmo- 
 sphere ; and the result is, that the skins undergo a kind of putrefactive or fermenting 
 process, by which the wool becomes loosened from the pelt. During this chemical 
 change ammonia is evolved in great abundance ; the odour is strong and disagreeable ; 
 a lighted candle, if introduced, would be instantly extinguished, and injurious effects 
 would be perceived by a person remaining long in one of the rooms. Each room is 
 about ten feet square, and is provided with nails and bars whereon to hang the lamb- 
 skins. The doors from all the rooms open into one common passage or vault, and are 
 kept close, except when the skins are inspected. It is a point of much nicety to deter- 
 mine when the fermentation has proceeded to such an extent as to loosen the wool from 
 the pelt ; for if it be allowed to proceed beyond that stage, the pelt itself would become 
 injured." 
 
 When the fermentation is completed, generally in about five days, the skins are re- 
 moved to a beam, and there ' slimed,' that is scraped on the flesh side, to remove a 
 slimy substance which exudes from the pores. The wool is then taken off, cleaned, 
 and sold to the hatters, for making the bodies of common hats. The stripped pelts are 
 steeped in lime-water for about a week, to kill the grease ; and are next ' fleshed on the 
 beam.' After being placed in a ' drench,' or a solution of sour bran for some days to 
 remove the lime and open the pores, the skins are alumed, and subjected to nearly the 
 same processes as the true kid-skins. ( See Leather. ) These Mediterranean lamb- 
 skins do not in general measure more than about 20 inches by 12 ; and each one fur- 
 nishes leather for two pairs of small gloves. These kinds of leather generally leave 
 the leather-dresser in a white state ; but undergo a process of dyeing, softening, 
 « stroking,' &c, before being cut up into gloves. 
 
 The tanning of one average-sized skin requires about 1^ lbs. of good Sicilian 
 sumach ; but for leather which is to receive a bright scarlet dye, from one half to three 
 quarters of a pound of gall-nuts are employed in preference. Inferior goat skins are 
 tanned with a willow bark infusion, in pits, in which they are turned repeatedly, and 
 laid out to drain, as in tanning sole leather. The finest skins for the brightest scarlet 
 are cured with salt, to prevent their receiving damage in the transport, and are dyed 
 before being tanned. This method is practised in Germany and France. 
 
 Leather of deer and sheep-skins is prepared with oil, for the purpose of making 
 breeches, &c, and for wash-leather, used in cleaning plate. After they are completely 
 washed, limed, and beamed, as above described, they have their ' grain 'surface re- 
 
LEATHER SPLITTING. 
 
 149 
 
 moved, to give them greater softness and pliability. This removal of the grain is 
 called 'frizing,' and it is done either with the round edge of a blunt knife, or with 
 pumice-stone. After being freed from the lime by steeping in fermented bran- water, 
 they are pressed as dry as may be, and are then impregnated with cod-oil, by beating 
 with stocks in the trough of a kind of a fulling-mill. Previously to the application of 
 the oil, they are usually beat for some time alone to open their substance. The oiled 
 skins are stretched, hung up for some time in the air, then fulled with oil as before — a 
 process which is 8 or 9 times repeated. The oil is slowly and evenly poured upon the 
 skins in the trough, during the action of the beaters. One hundred skins usually take 
 up in this way from two to three gallons of oil. The fulled oiled skins are thrown into 
 large tubs, and left for some time to ferment, and thereby to combine more intimately 
 with the oil. They are lastly subjected to a weak potash ley bath, to strip them of the 
 loosely adhering oil. They are then hung up in the air to dry, and dressed for the 
 market. 
 
 The quantity of hides and skins converted into leather yearly in England is almost 
 incredibly large. At Messrs. Bevington's establishment alone there are about 250,000 
 skins annually converted into leather by the aluming or tawing process ; 220,000 by 
 the sumach tanning process ; as also a small number by the oil-dressing process. For 
 the importation and exportation of skins untanned and tanned, see Hides. 
 
 In 1839, 5,149 Russian tanned hides were imported for home consumption; and in 
 1840, 4,664 ; of 5s. of duty on the entire hide; and pieces 2s. 6d. per lb. 
 
 The declared value of leather exported in 1840 was 320,912/. ; weight, 2,404,667 lbs. 
 Saddlery and harness of 96,167/. declared value were exported. 
 
 Leather gloves imported for home consumption in 1839, 991,623 pairs; in 1840, 
 1,503,862 ; average duty, 5s. a dozen. 
 
 LEATHER SPLITTING. This operation is employed sometimes upon certain 
 sorts of leather for glovers, for bookbinders, sheath-makers, and always to give a uni- 
 form thickness to the leather destined for the cotton and wool card-makers. 
 
 b h 
 
 Figs. 88, 89, 90, 91. represent a well contrived machine for that purpose; of which 
 fig. 88. shows the front view, fig. 89. a view from the left side, fig. 91. a ground plan, 
 
150 
 
 LEATHER SPLITTING. 
 
 and Jig. 90. a vertical section across the machine, a is a strong table, furnished with 
 four legs b, which to the right and left hand bears two horizontal pieces c. Each of 
 these pieces is cut out in front, so as to form in its substance a half-round fork, that 
 receives a cylinder d, carrying on its end a toothed spur-wheel e. Motion is com- 
 municated to the wheel by means of the handle /", upon whose axis the pinion, i, is fixed, 
 working into the wheel d, made fast to the end of the cylinder round which the leather 
 is rolled. The leather is fixed at one of its ends or edges to the cylinder, either with a 
 wedge pressed into a groove, or by a moveable segment of the cylinder itself. 
 
 The table, a, is cut out lengthwise with a slot, that is widened below, as shown in 
 Jig. 90. 
 
 The knife h (Jigs. 90. and 91.) is fixed flat upon the table with screw bolts, whose 
 
 heads are countersunk into the table, and secured with taps beneath (Jig. 90.), the edge 
 of the knife being placed horizontally over the opening, and parallel with it. 
 
 In Jig. 90. the leather, k, is shown advancing against the knife, getting split, and has 
 a portion coiled round the cylinder, which is made to revolve in proportion as the 
 leather is cleft. The upper portion of the leather is rolled upon the cylinder d, while 
 the under half, I, falls through the oblong opening upon the ground. 
 
 In regulating the thickness of the split leather, the two supports, m, act ; they are 
 made fast to the table a (one on each side of the knife), and are mortised into the table 
 by two tenons secured beneath. These supports are furnished near their tops with 
 keyed slots, by means of which the horizontal iron rod o(Jigs. 88. 90.) is secured, and 
 outside of the uprights they press upon the springs pp, which tend to raise the rod,o, in 
 its two end slots ; but the adjusting screws q, which pass down through the tops of the 
 supports into the mortise n (Jig. 90. ), and press upon the upper half of the divided tenon, 
 counteract the springs, and, accordingly, keep the rod, o, exactly at any desired height 
 or level. The iron rod, o, carries another iron bar, r, beneath it, parallel and also rectan- 
 gular, Jig. 90. This lower bar, which is rounded at its under face, lies upon and presses 
 the leather, by the action of two screws, which pass through two upright pieces s 
 (Jigs. 88. and 90. ), made fast to the table ; thus the iron bar, r, may be made to press 
 forwards the edge of the knife, and it may be adjusted in its degree of pressure, accord- 
 ing to the desired thickness of the leaf of split leather, that passes through under it. 
 
 Fig. 90. shows that the slant or obliquity of the knife is directed downwards, over 
 one of the edges of the oblong opening g ; the other edge of this opening is provided 
 with an iron plate t (Jigs. 90, 91.), which serves to guide the blade in cutting the leather 
 to the proper depth. For this purpose the plate is made adjustable by means of the 
 four springs u(Jigs. 90, 91.), let into the table, which pre^ it downwards. Four screws, 
 v, pass down through the table, each belonging to its respective springs u, and by means 
 of these screws the plate, t, may be raised in any desired degree. Each of the screws, 
 «, has besides a small rectangular notch, through which a screw bolt, x, passes, by 
 which the spring is made fast to the table. Thus also the plate, t, may be made to 
 approach to or recede from the knife. 
 
 y, in Jigs. 88. and 90., is a flat board, laid upon the leather a little behind the edge 
 of the plate t ; this board is pressed by the cylinder z, that lies upon it, and whose 
 tenons rest in mortises cut out in the two supports a'. The cylinder, z, is held in its 
 position by a wedge or pin b (Jigs. 88. and 89.), which passes through the supports. 
 When the leather has been split, these pins are removed, and the cylinder rises then by 
 means of two counter weights, not shown in the figures. 
 
 The operation of the machine is as follows : — The edge or end of the leather being 
 secured to the cylinder d, the leather itself having the direction upon the table, shown 
 in Jig. 90., and the bar, r, its proper position over the knife, the edge begins to enter in 
 
MADDER ROOT. 
 
 151 
 
 this position into the leather, while the cylinder, d, is moved by the handle or winch, and 
 the piece gets split betwixt the blade and the roller d. When the other end of the 
 'leather, k, advances to the knife, there is, consequently, one half of the leather split ; the 
 skin is to be then rolled off the cylinder d ; it is turned ; the already split half, or the 
 end of the leather k, is made fast into the wood of the cylinder, and the other half 
 is next split ; while the knife now acts from below, in an opposite direction to what 
 it did at first. 
 
 That the unrolling of the leather from the cylinder, d, may not be obstructed by the 
 pinion t, the stop-wedge e (Jiffs. 88, 89.) is removed from the teeth. In the process of 
 splitting, the grain side of the leather is uppermost, and is therefore cut of an uniform 
 thickness, but the under side varies in thickness with the inequality of the skin. 
 
 LINSEED. Imported for home consumption, in 1839, 3,852,359 bushels; in 
 1840, 3,256,257 ; \\d. duty. 
 
 LODES. The name given by the Cornish miners to metallic veins : as, tin lodes, 
 copper lodes, &c. 
 
 LOGWOOD; imported for home consumption in 1839, 17,209 tons; in 1840 
 18,683 tons ; duty 3s., foreign 4s. 6d. 
 
 M. 
 
 MACE. Imported for home consumption, in 1839, 21,154 pounds; in 1840, 
 16,813, duty 2s. 6d. per pound. 
 
 MADDER, GROUND; imported for home consumption in 1839, 96,702 cwts. ; 
 in 1840, 134,179 cwts. ; duty 2s. per cwt. 
 
 MADDER ROOT; in 1839, 80,259 cwts.; in 1840, 112,714 cwts. ; duty 6d. 
 per cwt. 
 
 A patent was granted in August, 1843, to Mr. F. Steiner, for the manufacture of 
 Garancine from used madder, formerly thrown away, as being exhausted of its dyeing 
 principle. His process is as follows : — "A large filter is constructed outside the 
 building in which the dye-vessels are situated, formed by sinking a hole in the ground, 
 and lining it at the bottom and sides with bricks without any mortar to unite them. 
 A quantity of stones or gravel is placed upon the bricks, and over the stones or gravel 
 common wrappering, such as is used for sacks. Below the bricks is a drain to take 
 off the water which passes through the filter. In a tub adjoining the filter is kept a 
 quantity of dilute sulphuric acid, of about the specific gravity of 105, water being 100. 
 Hydrochloric acid will answer the several purposes, but sulphuric acid is preferred as 
 more ceconomical. A channel is made from the dye-vessels to the filter. The madder 
 which has been employed in dyeing is run from the dye-vessels to the filter ; and 
 while it is so running, such a portion of the dilute sulphuric acid is run in and mixed 
 with it as changes the colour of the solution and the undissolved madder to an orange 
 tint or hue. This acid precipitates the colouring matter which is held in solution, and 
 prevents the undissolved madder from fermenting or otherwise decomposing. When 
 the water has drained from the madder through the filter, the residuum is taken from 
 off the filter and put into bags. The bags are then placed in an hydraulic press, to have 
 as much water as possible expressed from their consents. In order to break the lumps 
 which have been formed by compression, the madder or residuum is passed through a 
 sieve. To 5 cwt. of madder in this state, placed in a wood or lead cistern, 1 cwt. of 
 sulphuric acid of commerce is sprinkled on the madder through a lead vessel similar 
 in form to the ordinary watering-can used by gardeners. An instrument like a garden 
 spade or rake is next used, to work the madder about so as to mix it intimately with 
 the acid. In this stage the madder is placed upon a perforated lead plate, which is 
 fixed about five or six inches above the bottom of a vessel. Between this plate and 
 the bottom of the vessel is introduced a current of steam by a pipe, so that it passes 
 through the perforated plate and the madder which is upon it. During this process, 
 which occupies from one to two hours, a substance is produced of a dark brown colour 
 approaching to black. This substance is garancine and insoluble carbonized matter. 
 When cool, it is placed upon a filter and washed with clear cold water until the water 
 passes from it without an acid taste. It is then put into bags and pressed with an 
 hydraulic press. The substance is dried in a stove and ground to a fine powder under 
 ordinary madder stones, and afterwards passed through a sieve. In order to neutralize 
 any acid that may remain, from 4 to 5 lbs. of dry carbonate of soda for every hundred 
 weight of this substance is added and intimately mixed. The garancine in this state is 
 ready for use. 
 
152 
 
 MALT. 
 
 MALT. 
 
 The Quantity of Malt consumed by the undermentioned Brewers of London and its Vicinity, 
 from 10th October, 1830, to 10th October, 1842. 
 
 
 1831. 
 
 1832. 
 
 1833. 
 
 1834. 
 
 1835. 
 
 1836. 
 
 1837. 
 
 1838. 
 
 1839. 
 
 1840. 
 
 1841. 
 
 1842. 
 
 
 Qrs. 
 
 Qrs. 
 
 Qrs. 
 
 Qrs. 
 
 Qrs. 
 
 Qrs. 
 
 Qrs. 
 
 Qrs. 
 
 Qrs. 
 
 Qrs. 
 
 Qrs. 
 
 Qrs. 
 
 Barclay and Co. 
 
 97,19 
 
 J 96,615 
 
 1 93,17? 
 
 > 99,674 
 
 106,098 108,715 
 
 100,326 
 
 107,455 
 
 114,827 
 
 115,561 
 
 106,345 
 
 114,090 
 
 Hanbury and Co. 
 
 50,72 
 
 I 58,51' 
 
 1 58,49* 
 
 74,985 
 
 78,087 89,302 
 
 81,446 
 
 90,146 
 
 91.06L 
 
 98,216 
 
 88,135 
 
 92,406 
 
 Whitbread and Co. - 
 
 49,71 
 
 i 53,54 
 
 50,06' 
 
 49,10. r 
 
 55,209 53,094 
 
 47,012 
 
 45,466 
 
 51 ,971 
 
 53,622 
 
 51,457 
 
 52,098 
 
 Reid and Co. 
 
 43,38 
 
 ) 44,42( 
 
 ) 40,81 ( 
 
 44,2I( 
 
 49,430 49,831 
 
 42,706 
 
 44,928 
 
 44,016 
 
 48,130 
 
 47,986 
 
 50,120 
 
 Meux and Co. - 
 
 24,33 
 
 ) 22,065 
 
 ! 20,7 IS: 
 
 26,161 
 
 24,376 ! 30,77? 
 
 30,623 
 
 35,005 
 
 38,466 
 
 40,787 
 
 49,797 
 
 43,340 
 
 Combe and Co. 
 
 34,08- 
 
 1 36,94£ 
 
 36,07( 
 
 35,438 
 
 36,922 42,16£ 
 
 40,454 
 
 43,44i 
 
 40,712 
 
 38,36^ 
 
 36,466 
 
 40,484 
 
 Calvert and Co. 
 
 30,52 
 
 > 32,815 
 
 31,432 
 
 31.46C 
 
 33,263 30,85£ 
 
 32,325 
 
 31,52£ 
 
 31,02: 
 
 30,872 
 
 30,6J4 
 
 30,650 
 
 Hoare and Co. - 
 
 24,105 
 
 ! 20,82 
 
 25,407 
 
 29,796 
 
 31,525 32,622 
 
 32,347 
 
 31,27f 
 
 31,008 
 
 30,310 
 
 29,450 
 
 29,607 
 
 Elliot and Co. . 
 
 19,44* 
 
 20,061 
 
 19,89S 
 
 25,00£ 
 
 28,728 28,33!- 
 
 24,150 
 
 22,486 
 
 22,99f 
 
 25,367 
 
 25,379 
 
 27,050 
 
 Thorne, T. and Son - 
 
 1,44, 
 
 2.54C 
 
 5,i3e 
 
 8,496 
 
 10,913 12,657 
 
 16,404 
 
 18,545 
 
 19,578 
 
 20,864 
 
 22,413 
 
 22,022 
 
 Charrington and Co. 
 Steward and Co. 
 
 10,531 
 8,1 If 
 
 9,648 I 
 6,872 J 
 
 15,617 
 
 18,197 
 
 19,213 19,445 
 
 18,842 
 
 20,296 
 
 18,688 
 
 18,328 
 
 17,840 
 
 20 423 
 
 Taylor and Co. 
 
 21,845 
 
 21,735 
 14,874 
 
 21,11S 
 
 20,835 
 
 23,885 24,971 
 
 23,556 
 
 27,326 
 
 25,955 
 
 27,300 
 
 21,424 
 
 19,430 
 
 Goding, J. and Co. - 
 
 16,30/ 
 
 14,279 
 
 15,256 
 
 16,312 i 3,321 
 
 U14.023 
 7,095 
 
 14,028 
 
 12,14-= 
 
 { 18,517 
 
 16,018 
 
 Goding, Thomas 
 
 9,987 
 
 8,971 
 
 7,63C 
 
 8,824 
 
 7,616 
 
 1 1 ,78' 
 
 7,551 
 
 | 5,758 
 
 T7 fl71 
 
 Ramsbottom and Co. 
 
 
 
 
 51 5,30- 
 
 15,227 
 
 13,012 
 
 
 
 
 
 Broad wood and Co. - 
 
 
 
 
 
 
 10,616 
 
 14,630 
 
 15,791 
 
 16,688 
 
 Gardner, H. W. and P. 
 
 6,666 
 
 5,904 
 
 7,471 
 
 11,429 
 
 14,69i 
 
 15,36i 
 
 15,256 
 
 16,921 
 
 17,504 
 
 15,559 
 
 13,126 
 
 14,546 
 
 Mann, James - , - 
 
 
 1,056 
 7,607 
 
 1,332 
 
 1,757 
 
 8,079 
 
 2,78C 
 
 
 6,588 
 
 10,326 
 
 1 1 ,599 
 
 11,679 
 
 12,111 
 
 13,539 
 
 Courage and Co. 
 
 8,11.6 
 
 7,546 
 
 8,79C 
 
 9,23f 
 
 9,286 
 
 10,723 
 
 10,456 
 
 11,532 
 
 12,328 
 
 13,016 
 
 Wood and Co. - 
 
 5,469 
 
 5,560 
 
 5,547 
 
 7,602 
 
 7,326 
 
 7,96: 
 
 7,834 
 
 8,506 
 
 7,607 
 
 7,194 
 
 7,268 
 
 7,652 
 
 More, Robert - 
 
 2,535 
 
 1,040 
 
 1,890 
 
 4,713 
 
 4,136 
 
 5,255 
 
 6,025 
 
 6,129 
 
 6,413 
 
 6,954 
 
 7,175 
 
 7,026 
 
 Harris, Thomas 
 
 4,778 
 
 4,780 
 
 4,540 
 
 4,946 
 
 4,96' 
 
 4,99S 
 
 5,042 
 
 5,888 
 
 5,256 
 
 5,152 
 
 5,291 
 
 6,022 
 
 Hazard and Co. 
 
 - 
 
 6,126 
 
 6,203 
 
 7,094 
 
 86 
 
 
 6,591 
 
 6,674 
 
 6,552 
 
 6,250 
 
 6,729 
 
 5,758 
 
 5,556 
 
 Tubb, William 
 
 
 
 
 206 
 
 
 2,826 
 
 3,365 
 
 4,060 
 
 4,478 
 
 4,944 
 
 5,503 
 
 Richmond and Co. - 
 
 3,785 
 
 3,503 
 
 3,256 
 
 3,526 
 
 3,268 
 
 3^551 
 
 3,174 
 
 4,058 
 
 4,536 
 
 4,964 
 
 5,030 
 
 5,424 
 
 Hodgson and Co. 
 
 ) 4,200 
 
 3,522 
 
 3,870 
 
 2,086 
 
 2 41' 
 
 3 40( 
 
 2,400 
 
 1,790 
 
 5,358 
 
 5,704 
 
 5,862 
 
 
 
 
 4,983 
 
 Manners and Co. 
 
 
 
 
 
 
 
 4,552 
 
 6,121 
 
 7,030 
 
 5,334 
 
 4,8 9 
 
 4,831 
 
 Hale, George - 
 
 4,584 
 
 4,322 
 
 3,633 
 
 3,281 
 
 3,466 
 
 3,768 
 
 4,547 
 
 5,039 
 
 4,816 
 
 4,443 
 
 4,418 
 
 4,468 
 
 Halford and Co. ? 
 
 3,215 
 
 3,187 
 
 3,330 
 
 3,545 
 
 
 3,762 
 
 3,786 
 
 4,685 
 
 3,967 
 
 3,585 
 
 
 Kempson and Co. J 
 
 
 
 
 
 
 3,155 
 
 3,878 
 
 Farren and Till 
 
 I - 
 
 3,139 
 
 3,217 
 
 - 
 
 
 4,04c 
 
 4,783 
 
 4,599 
 
 4,400 
 
 4,425 
 
 Thorne, J. M. and Son 
 
 
 
 
 
 3,860 
 
 3,676 
 
 Duggan and Co. 
 
 I ■ 
 
 
 
 
 
 2,201 
 
 2,665 
 
 2,288 
 
 3,020 
 
 3,001 
 
 2,574 
 
 Gaskell and Downs - 
 
 
 
 
 
 
 
 
 
 
 3,354 
 
 Mc. Leod, B. - 
 
 1,656 
 
 2,947 
 
 4,236 
 
 5,479 
 
 5,360 
 
 4,689 
 
 4,9G0 
 
 4,700 
 
 4,300 
 
 3,410 
 
 3,305 
 
 3,125 
 
 Plimmer 
 
 
 
 
 
 
 
 788 
 
 1 ,653 
 
 3,001 
 
 Laxton and Bryan - 
 
 4,048 
 
 3,020 
 
 2,941 
 
 3,508 
 
 4,187 
 
 3,573 
 
 3,583 
 
 3,167 
 
 3,213 
 
 2,658 
 
 2,579 
 
 2.797 
 
 Draper and Co. 
 
 
 
 1,658 
 
 1,711 
 
 1,787 
 
 2,777 
 
 Miller and Co. 
 
 
 
 
 
 
 
 
 
 855 
 
 1,167 
 
 1,740 
 
 2 685 
 
 Keene and Co. 
 
 
 
 
 
 
 
 
 
 2,326 
 
 2,345 
 
 2,645 
 
 2,445 
 
 Lane and Bowden 
 
 
 
 
 
 
 
 88 
 
 393 
 
 1,275 
 
 1,964 
 
 2,010 
 
 2,432 
 
 Fleming and Co. 
 
 
 
 
 
 
 
 
 1,787 
 
 1,795 
 
 2,159 
 
 2,417 
 
 2,256 
 
 Clarke, Charles 
 
 814 
 
 857 
 
 1,006 
 
 1,003 
 
 1,006 
 
 1,249 
 
 1,330 
 
 1,624 
 
 1,848 
 
 1,934 
 
 2,124 
 2,597 
 
 2,255 
 
 Gurney, J. and Co. - 
 
 
 
 A 614 
 3,072 
 
 1,903 
 
 2,211 
 
 Stains and Fox 
 
 2,235 
 
 1,832 
 
 2,163 
 
 2,266 
 
 3,106 
 
 3,738 
 
 3,783 
 
 3,749 
 
 2,406 
 
 2,528 
 
 2,050 
 
 Verey, W. and G. 
 
 - 
 
 - 
 
 844 
 
 1,140 
 375 
 
 1,208 
 
 1,302 
 
 1,573 
 
 1,735 
 
 1,749 
 
 1,762 
 
 1,825 
 
 1,840 
 
 Jones, T. - 
 
 585 
 
 463 
 
 337 
 
 248 
 
 700 
 
 956 
 
 1,338 
 
 1 ,555 
 
 1,879 
 
 1,810 
 
 1,808 
 
 Herington and Wells 
 
 
 
 
 
 
 
 
 
 1,538 
 
 1,905 
 
 1,746 
 
 1,806 
 
 Hill and Rice - 
 
 2,910 
 
 1,748 
 
 1,974 
 
 1,963 
 
 2,042 
 
 1,872 
 
 1,853 
 
 1,911 
 
 1,835 
 
 1,677 
 
 1,697 
 
 1,628 
 
 Holt and Sons - 
 
 1,113 
 
 754 
 
 717 
 
 794 
 
 734 
 
 813 
 
 756 
 
 846 
 
 807 
 
 1,093 
 
 972 
 
 1,583' 
 
 Cox, John 
 
 2,302 
 
 2,279 
 
 4,371 
 
 2,446 
 
 2,499 
 
 2,018 
 
 2,151 
 
 1,991 
 
 1,861 
 
 1,723 
 
 1,528 
 
 1,520 
 
 Griffith, P. 
 
 2,146 
 
 1,530 
 
 1,063 
 
 1,693 
 
 2,120 
 
 2,394 
 
 2,221 
 
 1,884 
 
 1,553 
 
 1,916 
 
 1,419 
 
 1,429 
 
 Ufford and Co. 
 
 - 
 
 - 
 
 - 
 
 203 
 
 472 
 
 731 
 
 953 
 
 1,291 
 
 1,241 
 
 1,201 
 
 1 ,350 
 
 1,360 
 
 Masterman and Co. - 
 
 1,704 
 
 1,803 
 
 1,830 
 
 1,810 
 
 1,877 
 
 1,789 
 
 1,914 
 
 1,847 
 
 1,789 
 
 1,672 
 
 1,892 
 
 1,295 
 
 Johnson and Co. - 7 
 
 - 
 
 - 
 
 - 
 
 - 
 
 
 2,809 
 
 2,809 
 
 2,428 
 
 2,412 
 
 2,413 
 
 2,204 
 
 
 
 
 
 
 
 
 
 1,267 
 
 Turner, R. 
 
 98 
 
 128 
 
 218 
 
 341 
 
 531 
 
 716 
 
 712 
 
 897 
 
 1,013 
 
 1,077 
 
 1,219 
 
 1,254 
 
 Dickenson, G. - 
 Honeyball, Edward - 
 
 901 
 
 719 
 
 801 
 
 793 
 
 838 
 
 1,037 
 
 1,025 
 
 1,010 
 
 1,020 
 
 1,100 
 
 1,092 
 
 1,135 
 1,087 
 
 
 - 
 
 269 
 
 471 
 
 800 
 
 1,103 
 
 1,512 
 
 1,714 
 
 1,402 
 
 1,155 
 
 1,053 
 
 Jenner, R. and H. - 
 
 
 202 
 
 355 
 
 529 
 
 734 
 
 772 
 
 833 
 
 925 
 
 856 
 
 929 
 
 955 
 
 1,067 
 
 Church, J. L. - 
 
 
 
 
 
 
 756 
 
 742 
 
 672 
 
 975 
 
 949 
 
 1,049 
 
 1 ,065 
 
 Blogg, B. - 
 M'Leod,.J.M. and Co.. 
 
 603 
 
 684 
 
 594 
 
 752 
 
 968 
 
 1,067 
 
 943 
 
 1,006 
 978 
 
 1,143 
 
 1,034 
 782 
 
 1,113 
 
 1,045 
 
 
 - 
 
 - 
 
 - 
 
 
 748 
 
 820 
 
 877 
 
 797 
 
 1,025 
 
 Satchel! and Son 
 
 2,508, 
 
 3,117 
 
 1,906 
 
 2,515 
 
 2,147 
 
 2,177 
 
 1,441 
 
 1,431 
 
 1,475 
 
 1,308 
 
 1,063 
 
 945 
 
 
 
 78 
 
 883 
 
 865 
 
 Chadwick, W. 
 
 
 
 
 
 
 
 169 
 
 361 
 
 532 
 
 775 
 
 820 
 
 846 
 
 Turner, John - 
 
 674 
 
 584 
 
 640 
 
 677 
 
 709 
 
 786 
 
 766 
 
 821 
 
 853 
 
 728 
 
 768 
 
 754 
 
 Lock, R.- 
 
 
 99 
 
 259 
 
 422 
 
 496 
 
 620 
 
 651 
 
 725 
 
 760 
 
 776 
 
 765 
 
 737 
 
 Hume, George - 
 
 1 018 
 
 985 
 
 975 
 
 1,427 
 
 1,256 
 
 1,235 
 
 1,126 
 
 1,160 
 
 812 
 
 791 
 
 718 
 
 708 
 
 Collins, W. L. - 
 
 '205 
 
 176 
 
 254 
 
 441 
 
 519 
 
 527 
 
 598 
 
 407 
 
 3G2 
 
 620 
 
 627 
 
 705 
 
 West, J. H. 
 
 846' 
 
 577 
 
 394 
 
 322 
 
 406 
 
 406 
 
 565 
 
 749 
 
 594 
 
 627 
 
 708 
 
 702 
 
 Mantell and Son 
 
 1,1871 
 756 
 
 840 
 
 914 
 
 850 
 
 757 
 
 807 
 
 693 
 
 650 
 
 694 
 
 723 
 
 641 
 
 650 
 
 Addison - 
 
 590 
 
 596 
 
 653 
 
 671 
 
 619 
 
 768 
 
 812 
 
 637 
 
 72 
 
 638 
 
 642 
 
 
 
 
 
 
 
 397 
 
 501 
 
 549 
 
 592 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 ■ 637 
 
 640 
 
 
 | 
 
 
 271 
 
 488 
 
 671 
 
 839 
 
 649 
 
 531 
 
 504 
 
 594 
 
 644 
 
 624 
 
 Clarke, W 
 
 
 
 
 
 
 
 
 
 
 462 
 
 506 
 
 529 
 
 Clarke. S. 
 
 722 
 
 841] 
 
 876 
 
 938 
 
 793 
 
 837 
 
 741 
 
 768 
 
 547 
 
 450 
 
 502 
 
 520 
 
 Bye, W. and H. 
 
 
 
 
 
 
 201 
 
 260 
 
 346 
 
 433 
 
 489 
 
 510 
 
 Clark - - > 
 
 
 719: 
 
 780 
 
 747 
 
 706 
 
 853 
 
 834 
 
 983 
 
 
 
 
 501 
 
 Rudge j 
 
 
 
 
 
 
 
 
 
 886 
 
 555 
 
 449 
 
MATCHES, LUCIFER. 
 
 153 
 
 
 1831. 
 
 1832. 
 
 1833. 
 
 1834. 
 
 1835 
 
 1836. 
 
 1837. 
 
 1838. 
 
 1839. 
 
 1840. 
 
 1841. 
 
 Bricheno, Henry 
 
 Qrs. 
 
 Qrs. 
 
 Qrs. 
 
 Qrs. 
 
 Qrs. 
 
 Qrs. 
 
 Qrs. 
 
 Qrs. 
 
 Qrs. 
 
 Ore 
 
 Qrs. 
 
 Qrs. 
 
 5,637 
 
 5,732 
 
 7,120 
 
 9 950 
 
 9,762 
 
 9,885 
 
 9 863 
 
 8 857 
 
 8 6'jE 
 
 
 
 Lamont and Co. 
 
 1,646 
 
 356 
 
 883 
 
 657 
 
 402 
 
 2'()85 
 
 3600 
 
 5' 251 
 
 7*63* 
 
 f 13,475 
 J 
 
 13,087 
 
 Filmer and Gooding - 
 
 
 
 
 
 
 1 ,039 
 
 1 298 
 
 1 291 
 
 1 674 
 
 1 633 
 
 1 ,514 
 
 Wood and Co. - 
 
 
 
 
 
 
 
 
 
 1^493 
 
 1 ,442 
 
 1,484 
 
 Brown, late Hicks 
 
 
 
 
 
 
 
 
 
 1 ,351 
 
 1,450 
 
 1 300 
 
 Manvell, Isaac - 
 
 752 
 
 713 
 
 924 
 
 875 
 
 834 
 
 805 
 
 824 
 
 756 
 
 579 
 
 732 
 
 770 
 
 Abbott, E. 
 
 691 
 
 
 525 
 
 G:J4 
 
 654 
 
 2,305 
 
 560 
 
 441 
 
 312 
 
 487 
 
 490 
 
 Cooper, W. 
 
 244 
 
 
 443 
 
 
 199 
 
 310 
 
 315 
 
 370 
 
 434 
 
 503 
 
 485 
 
 
 
 
 
 
 
 
 
 81 
 
 311 
 
 362 
 
 471 
 
 Harris, Robert - 
 
 
 
 179 
 
 255 
 
 4C6 
 
 295 
 
 306 
 
 251 
 
 290 
 
 353 
 
 444 
 
 
 
 451 
 
 490 
 
 557 
 
 497 
 
 470 
 
 456 
 
 405 
 
 447 
 
 441 
 
 Barrels of Beer brewed by each of the Twelve principal Brewers in London. 
 
 1782. 
 
 Whitbread - 
 Calvert, Felix 
 Truman 
 Calvert, John 
 Thrale, Mrs. 
 Hammond - 
 Phillips 
 Goodwyn 
 Meux 
 Jordan 
 Dawson 
 Dickinson - 
 
 Meux 
 Barclay 
 Golden Lane 
 Hanbury - 
 Whitbread 
 Combe 
 Goodwyn - 
 Calvert, Felix 
 Elliot 
 Biley 
 Harford 
 Calvert, John 
 
 ■ 190,169 
 
 - 184,196 
 
 - 131,647 
 
 - 117,574 
 
 - 112,472 
 
 - 70,547 
 
 - 70,232 
 
 ■ 68,894 
 • 48,660 
 . 38,029 
 . 32,800 
 
 - 32,022 
 
 2,097,231 
 
 Quarters of Malt consumed in the undermentioned Years ending 10th October. 
 
 By the Brewers of London and its Vicinity, 
 
 1831 622,549 1833 578,588 1835 702,533 1837 714,488 i 1839 750,176 [ 1841 734,295 
 
 1832 694.477 1834 662,713 1836 754,313 1838 742,597 | 1840 776,219 I 1842 741,651 
 
 By the Twelve principal Brewers of London. 
 
 1831 
 
 432,521 
 
 1833 
 
 427,087 
 
 1835 
 
 503,048 
 
 1837 
 
 490,179 
 
 1839 
 
 528,259 
 
 1841 
 
 1832 
 
 438,046 
 
 1834 
 
 470,123 
 
 1836 
 
 526,092 
 
 1838 
 
 517,940 
 
 1840 
 
 547,908 
 
 1842 
 
 MANGANESE, OXIDE OF; for a simple method of ascertaining the value of 
 this substance in the production of chlorine, and the manufacture of the chlorides and 
 chlorates, see Chemistry Simplified, in the Appendix. 
 
 MANURE. A patent -for an excellent article of this kind was obtained in May, 
 1842, by J. B. Lawes, Esq. He decomposes bones, apatite, and other subphosphates 
 of lime by mixing them in powder with as much sulphuric acid as will liberate 
 enough of the phosphoric to dissolve the phosphate of lime. The free phosphoric acid 
 is thereby ready to combine with the various alkaline earths contained in the soil, 
 while the phosphate of lime is brought to a state of more minute division than is 
 possible by mechanical means. Mr. Lawes also proposes to mix the above soluble 
 superphosphate with such alkalies as are deficient in the soil, and thus to form a 
 manure adapted to fertilise it. His third improvement in manure is the formation 
 and application of a liquor of flints, for such soils as are deficient in soluble silica. 
 The last compound he considers to be valuable for grounds much cropped with wheat 
 and other cereals that require a good deal of silica for their growth. 
 
 MARGARIC ACID is obtained most easily by the distillation of stearic acid. 
 The humidity at the beginning of the process must be expelled by a smart heat, other- 
 wise explosive ebullitions are apt to occur. Whenever the ebullition becomes uniform, 
 the fire is to be moderated. 
 
 MATCHES, LUCIFER. According to Dr. R. Boeltger, in Anna 'en der Chemie 
 und Pharmacie, vol. xlvii. p. 334., take 
 
 Phosphorus _ 3 . - - 4 parts 
 
 Nitre - - - - - 10 — 
 
 Fine glue - - - - 6 — 
 
 Red ochre, or red lead •• - -5 — 
 
 Smalt - - - - 2 — 
 
 X 
 
154 
 
 METALLIC ANALYSIS. 
 
 Convert the glue with a little water by a gentle heat into a smooth jelly, put it into a 
 slightly warm porcelain mortar to liquefy ; rub the phosphorus down through this gela- 
 tine at a temperature of about 140° or 150° Fahr. ; add the nitre, then the red powder, 
 and lastly the smalt, till the whole forms a uniform paste. To make writing-paper 
 matches, which burn with a bright flame and diffuse an agreeable odour, moisten each 
 side of the paper with tincture of benzoin, dry it, cut it into slips, and smear one of 
 their ends with a little of the above paste by means of a hair pencil. On rubbing the 
 said end after it is dry against a rough surface the paper will take fire, without the 
 intervention of sulphur. 
 
 To form Inciter wood matches, that act without sulphur, melt in a flat-bottomed 
 tin pan as much white wax as will stand one-tenth of an inch deep ; take a bundle of 
 wooden matches free from resin, rub their ends against a red hot iron plate till the wood 
 be slightly charred ; dip them now in the melted wax for a moment, shake them well 
 on taking them out, and finally dip them separately in the above viscid paste. When 
 dry, they will kindle readily by friction. 
 
 For the rapid manufacture of the wooden splints for lucifer matches, a patent was 
 granted to Mr. Reuben Partridge^ in March, 1842. He employs a perforated 
 metallic plate, having a steel face, strengthened by a bell metal back ; see Jigs. 
 92, 93. The size of the perforations must depend on that of the desired splints, but they 
 must be as close together as possible, that there raa) be a very small blank space bc- 
 
 92 
 
 93 
 
 tween them, otherwise the plate would afford too great resistance to the passage of the 
 wood. Ry this construction, the whole area of the block of wood may be com- 
 pressed laterally into the countersunk openings, and forced through the holes, which 
 are slightly countersunk to favour the entrance and separation of the wooden fibres. 
 Fig. 92. represents the face of one of these plates ; and fig. 93. is a rectangular section 
 through the plate. A convenient size of plate is three inches broad, six inches long, 
 and one thick. The mode of pressing is by fixing the back of the plate against a firm 
 resisting block or bearing, having an aperture equal to the area of the°perforations 
 in the plate, and then placing the end of the piece or pieces of wood in the direction 
 of the grain against the face of the plate within the area of the perforated portion. A 
 plunger or lever or other suitable mechanical agent being then applied to the back or 
 reverse end of the piece of wood, it may be forced through the perforations in the 
 plate, being first split as it advances by the cutting edges of the holes, and afterwards 
 compressed and driven through the perforations in the plate, coining out on the 
 opposite side or back of the plate in the form of a multitude of distinct splints, agree- 
 ably to the shapes and dimensions of the perforations. — {Newton's Journal, C. S. 
 vol. xxii. 268.) 
 
 MERCURY ; imported for home consumption in 1839, 340,469 pounds; in 1840, 
 330.070 pounds; duty Id. per pound. 
 
 METALLIC ANALYSIS. Professor Liebig has lately enriched this most useful 
 department of practical chemistry, by the employment of the cyanide of potassium 
 
METALLIC STATISTICS. 
 
 loo 
 
 prepared in his economical method (see this article). This salt is the best re agent for 
 detecting nickel in cobalt. The solution of the two metals being acidulated, the cyanide 
 is to be added until the precipitate that first falls is redissolved. Dilute sulphuric acid 
 is then added, and the mixture b;'ing warmed and left in repose, a precipitate does not 
 fail to appear sooner or later, which is a compound of nickel. Cyanide of potassium 
 serves well to separate lead, bismuth, cadmium, and copper, four metals often associated 
 in ores. On adding the cyanide in excess to the solution of these metals in nitric acid, 
 lead and bismuth fall as carbonates, and may be parted from each other by sulphuric 
 acid. Sulphuretted hydrogen is passed in excess through the residuary solution, and 
 the mixture being heated, a small quantity of cyanide is added : a yellow precipitate 
 indicates cadmium ; and a black precipitate falls on the addition of hydrochloric acid, 
 if copper be present. 
 
 If into a crucible (containing the cyanide fused by heat), a little of any metallic 
 oxide be thrown at intervals, it will be almost immediately reduced to the reguline state, 
 When the fluid mass is afterwards decanted, the metal will be found mixed with the 
 white saline matter, from which it may be separated by water. 
 
 Even metallic sulphurets are reduced to the state of pure metals by being projected 
 in a state of fine powder into the fused cyanide. When an iron ore is thus introduced, 
 along with carbonate of potash or soda, and the mixture is heated to fusion, which 
 requires a strong red heat, the alumina and silica of the ore fuse into a slag ; from 
 which, on cooling, the metallic iron may be separated by the action of water, and then 
 weighed. If manganese exist in the ore, it remains in the state of protoxide; to be 
 determined by a separate process. When oxide of copper is sprinkled on the surface of 
 the fused cyanide, it is immediately reduced, with the disengagement of heat and light. 
 The mixture being poured out of the crucible and concreted, is to be ground and 
 washed, when a pure regulus of copper will be obtained. 
 
 The process of reduction is peculiarly interesting with the oxides of antimony and 
 tin ; being accomplished at a low red heat, hardly visible in day-light. Even the 
 sulphurets of these metals are immediately stripped of their sulphur, with the form- 
 ation of sulpho-cyanide of potassium. 
 
 Cyanide of potassium, mixed with carbonate of soda, is an excellent re-agent in 
 blow-pipe operations for distinguishing metals. The reductions take place with the 
 utmost facility, and the fused mixture does not sink into the charcoal, as carbonate of 
 soda alone is apt to do in such cases. Hence the grains or beads of metal are more 
 visible and can be better examined. 
 
 When the cyanide is heated along with the nitrates and chlorates (of potash), it 
 causes a rapid decomposition, accompanied with light and explosions. 
 
 Arsenic may be readily detected in the commercial sulphuret of antimony, by fusing 
 it with three-fourths of its weight of the cyanide in a porcelain crucible over a spirit 
 lamp, when a regulus of antimony is obtained. The metal may then be easily tested 
 for arsenic, since none of this volatile substance can have been lost, owing to the low 
 temperature employed. 
 
 When arsenious acid, or orpiment, or any of the arseniates, are mixed with six times 
 their weight of the mixture of cyanide and carbonate of soda in a tube with a bulb at 
 one end, and heat applied with a spirit lamp to the glass, very beautiful rings of me- 
 tallic mirror are formed by the reduced arsenic. The arseniates of lead and of peroxide 
 of iron, however, do not answer to this test. 
 
 When sulphates of lead and barytes, along with silica, are mixed with four or five 
 times their weight of the above mixed cyanide and carbonate, and fused, the sulphate 
 of lead is reduced to the metallic state, the sulphate of barytes becomes a carbonate, 
 and the silica gets combined with the alkali into a soluble glass. 
 
 METALLIC STATISTICS. By the returns to five several orders made by the 
 House of Commons, which were obtained by the exertions and perseverance of Sir J. 
 J. Guest, Sir C. Lemon, and Mr. Evans (M. P. for North Derbyshire), we are en- 
 abled to lay before our readers a most correct account of the various exports, and 
 imports of iron and iron ore, hardware, cutlery, &c, copper ore, copper, tin, zinc, lead 
 ore, and lead, for the year ending Jan. 5. 1844. 
 
 Commencing with iron, it appears there was imported in the year, iron ore, 131 
 tons; chromate of iron, 1393 tons; pig-iron, 243 tons; unwrought iron in bars, 
 12,795 tons; bloom, 563 tons; rod-iron, 12 tons; old, broken, and cast-iron, 286 
 tons; cast-iron, only 8 tons ; steel, unwrought, 1697 tons — of these, 97 tons only 
 were entered by weight, the remainder by value, 11,035/. 6s. 9d. Of the several 
 countries from which these importations came the principal is Sweden, whence we 
 have received of iron 10,909 tons, and steel 1558 tons, leaving but a small portion to 
 divide between twenty other places. — Our exports of foreign iron have been, unwrought 
 in bars, 3986 tons; rod, 10 tons; hoops, 2 tons; cast-iron, 11 cwt. ; steel, unwrought, 
 1456 tons. The total quantity of foreign iron retained for home consun ption was 
 
 X 2 
 
156 
 
 METALLIC STATISTICS. 
 
 14,782 tons, upon which the net amount of duty was 14,563/. — The exportation of 
 that staple produce of our own country, British iron, was as follows : — Bar-iron, 
 176,148 tons; bolt and rod, 22,625 tons; pig-iron, 154,770 tons; cast-iron, 16,449 
 tons; iron wire, 1508 tons; wrought-iron, consisting of anchors, grapnels, &c, 3058 
 tons; hoops, 14,591 tons; nails, 6020 tons; and all other sorts, except ordnance, 
 44,577 tons; old iron for manufacture, 5924 tons; and unwrought steel, 3199 tons. 
 Those places which have taken the greatest portions of this produce are — Russia, 
 10,963 tons of bar-iron ; Denmark, 10,447 tons bar, and 7010 tons pig; Prussia, 
 12,009 tons bar, 17,480 tons pig ; Germany, 13,298 tons bar, 6322 tons pig, 1339 tons 
 cast ; Holland, 17,509 tons bar, 75,953 tons pig; 4317 tons cast ; Belgium, 4279 tons 
 cast ; France, 4237 tons bar, 22,103 tons pig ; Italy, 21,930 tons bar, 3982 tons bolt 
 and rod, 3005 tons pig; Turkey, and Continental Greece, 6412 tons bar ; East Indies 
 and Ceylon, 20,620 tons bar, 2967 tons bolt ; British North American Colonies, 6837 
 tons bar, 1995 tons cast; Foreign West Indies, 5043 tons bar, 1646 tons cast ; and to 
 the United States, 21,336 tons bar, and 7148 tons pig. The largest quantity of 
 unwrought steel has been to the latter place — viz., 1336 tons. 
 
 Of British hardware and cutlery, we exported in the year 17,183 tons, valued at 
 1,745,518/. ; the principal of which has been — to Germany, 1237 tons, value 159,889/. ; 
 East Indies, 1402 tons, value 142,607/. ; British North American Colonies, 1129 tons, 
 value 102,260/. ; British West Indies, 997 tons, value 80,040/. ; Foreign West Indies, 
 657 tons, value 48,609/. ; United States, 4282 tons, value 448,341/. ; Brazil, 943 tons, 
 value 80,070/. ; and divers other places, varying from 100 to 500 tons. 
 
 We now come to copper. Of foreign copper ores, we have imported 55,720 tons ; 
 and of metallic copper, unwrought and wrought plates, and coins, 805 tons. Of the 
 ores, the greatest quantities have come from* Cuba and Chili. 
 
 We have exported 1819 tons of British, and 650 tons of foreign tin — of which 
 France has taken 626 tons, Russia 480 tons, Italy 183 tons, Turkey 250 tons, and the 
 remainder distributed among twenty-seven places. 
 
 Of foreign zinc, we have imported as follows : — 
 
 Countries from whence imported. 
 Denmark - 
 Prussia - 
 Germany 
 Holland 
 
 Belgium - 
 Syria and Palestine 
 
 Tons. 
 
 cwt. 
 
 qrs. 
 
 lbs. 
 
 268 
 
 19 
 
 2 
 
 21 
 
 6860 
 
 15 
 
 3 
 
 22 
 
 3000 
 
 1 
 
 2 
 
 11 
 
 20 
 
 3 
 
 2 
 
 1 
 
 21 
 
 9 
 
 0 
 
 9 
 
 1 
 
 15 
 
 0 
 
 15 
 
 Total import of foreign zinc - Tons 10,173 4 3 23 
 
 Of this, we retained for home consumption 4102 tons, on which the net duty was 
 223/. 2s. 10c?. ; and we have exported 1395 tons of British, and 6445 tons of foreign 
 spelter. 
 
 Of foreign lead, we have imported 2863 tons — of which 2775 tons were pig and 
 sheet, 68 tons ore, and 19 tons white lead ; 157 tons were retained for home con- 
 sumption, on which the duty was 165/. ; and we imported from the Isle of Man, duty 
 free, 2415 tons of lead ore. Our exportation of foreign lead amounted to 2439 tons — 
 while of British, we exported, 176 tons of ore, 14,610 tons pig and sheet, 378 tons 
 litharge, 707 tons red lead, and 1224 tons white lead — making a total of 17,097 tons. 
 — Railway and Commercial Gazette, May 18. 1844. 
 
 METER, GAS. Since the article Gas was printed I have had occasion to ex- 
 amine very carefully the construction, performance, and comparative merits of the four 
 gas-meters most generally used in Great Britain, and have been led to conclude th 
 the surmises concerning the correctness of the indications of several of them arc 
 too well founded. The instruments on which my observations were made were all 
 new, and just out of the hands of their respective patentees. 
 
 1. The meter of Mr. West is, no doubt, accurate while the water-line is rightly 
 adjusted ; but as I find that it will admit an extra pint of water, it may be rendered 
 unjust towards the consumers of gas; and then if it receives a little more water by con- 
 densation of vapour, or by accident, its siphon gets filled, which causes the extinction 
 of the lights. 
 
 2. The meter of Mr. Bottom has also several defects, and occasions nuisance by letting 
 its overflow water trickle upon the floor. 
 
 3. The meter of Mr. Crossley may oe maae to err in its measurements fully 20 per 
 cent, by dexterous repletion with water, and that in favour of the gas companies. 
 
 These three meters are furnished with the vertical float-valve, so apt to rust and stick ; 
 
MINES. 
 
 157 
 
 they also allow gas to escape at the discharge plug, to the imminent risk of occasion- 
 ing fire with ignorant or careless servants ; and finally, they have the complex dial-plate 
 indexes, so liable to misapprehension. 
 
 4. The meter of Mr. Edge. This instrument is quite exempt from all the above 
 defects, and is equally delicate and just in its indications, being mounted with a lever 
 valve of great mobility, and a new index, which any one who knows numbers cannot 
 miscount. I have subjected this meter to every kind of test, and find that it cannot 
 be made to give false indications, either by awkwardness or intention. Its inventor is 
 therefore well entitled to the warm patronage both of the public and all gas companies 
 who love fair dealing. 
 
 MILK has been adulterated with a solution of potato starch, from which it derives 
 a creamy consistence. This fraud may he detected by pouring a few drops of iodine 
 water into it, which immediately causes it to assume a blue or purple tint. Emulsion 
 of sweet almonds, with which the milk at Paris has been adulterated, may be readily 
 detected by the taste. 
 
 MINES. The miner, in sinking into the earth, soon opens up numerous springs, 
 whose waters, percolating into the excavations which he digs, constitute one of the greatest 
 obstacles that nature opposes to his toils. When his workings are above the level of 
 some valley and at no great distance, it is possible to get rid of the waters by leading them 
 along a trench or a gallery of efflux. This forms always the surest means of drainage ; 
 and notwithstanding the great outlay which it involves, it is often the most economical. 
 The great advantages accruing from these galleries, lead to their being always estab- 
 lished, and without risk, in mines which promise a long continuance. There are many 
 galleries several leagues in length ; and sometimes they are so contrived as to discharge 
 the waters of several mines, as may be seen, in the environs of Freyberg. Merely such 
 a slope should be given them as is barely sufficient to make the water run, at the utmost 
 from to ^lg, so as to drain the mine to the lowest possible level. 
 
 Whenever the workings are driven below the natural means of drainage, or below 
 the level of the plain, recourse must be had to mechanical aids. In the first place, the 
 quantity of percolating water is diminished as much as possihle by planking, walling, 
 or caulking-up with the greatest possible care those pits and excavations which traverse 
 the water levels ; and the lower workings are so arranged that all the waters may unite 
 into wells placed at tho bottom of the shafts or inclined galleries ; whence they may be 
 pumped up to the day, or to the level of the gallery of efflux. In most mines, simple 
 sucking pumps are employed, because they are less subject to give way, and more easy 
 of repair; and as many of these are placed over each other, as the shaft is ten yards 
 deep, below the point where the waters have a natural run. 
 
 These draining machines are set in motion by that mechanical power which happens 
 to be the least costly in the place where they are established. In almost the whole of 
 England, and over most of the coal mines of France and Silesia, the work is done by 
 steam engines ; in the principal metallic mines of France, and in almost the whole of 
 Germany and Hungary, by hydraulic machines ; and in other places, by machines 
 moved by horses, oxen, or even by men. If it be requisite to lift the waters merely to 
 the level of a gallery of efflux, advantage may be derived from the waters of the upper 
 parts of the mine, or even from waters turned in from the surface, in establishing in the 
 mine of the gallery-level, water-pressure machines, or overshot water-wheels, for pump- 
 ing up the lower water. This method is employed with success in several mines of Hun- 
 gary, Bohemia, Germany, Derbyshire, Cornwall, in those of Poullaouen in Brittany, &c. 
 It has been remarked, however, that the copious springs are found rather towards the 
 surface of the soil than in the greatest depths. 
 
 TRANSPORT OF ORES TO THE SURFACE. 
 
 The ore being extracted from its bed, and having undergone, when requisite, a first 
 sorting, it becomes necessary to bring it to the day, an operation performed in different 
 ways according to circumstances and localities, but too often according to a blind 
 routine. There are mines at the present day, where the interior transport of ores is 
 executed on the backs of men ; a practice the most disadvantageous possible, but which 
 is gradually wearing out. The carriage along galleries is usually effected by means of 
 hurdles, barrows, or, still better, by little waggons. These consist of frames resting on 
 four wheels ; two larger, which are placed a little behind the centre of gravity, and two 
 smaller, placed before it. When this carriage is at rest, it bears on its four wheels, and 
 leans forwards. But when the miner, in pushing it before him, rests on its posterior 
 border, he makes it horizontal ; in which case it rolls only upon the two larger wheels. 
 Thus, the friction due to four wheels is avoided, and the roller or driver bears no part 
 of the burden, as he would do with ordinary wheelbarrows. To ease the draught still 
 more, two parallel rails of wood or iron are laid along the floor of the gallery, to which 
 
153 
 
 MINES. 
 
 the wheels of the carriage are adjusted. It is especially in metallic mines, where the ore 
 is heavy, and the galleries straight, that these peculiar waggons are employed. In coal 
 mines, carriages formed with a much larger basket, borne on a rail-road by four equal 
 wheels, are preferred. Sometimes the above wain, called on the Continent a dog (chien), 
 is merely a simple frame on four wheels, on which a basket is set. In the great mines, 
 such as many of the coal and saltmines of Great Britain, the salt mines of Gallicia, the 
 copper mines of Fahlun, the lead mines of Alston-Moor, horses and asses are introduced 
 into the workings to drag heavier waggons, or rather a train of waggons attached to 
 one another. These animals often live many years under ground, without ever revisit- 
 ing the light of day. In other mines, such as those of Worsley, in Lancashire, subter- 
 ranean canals are cut, upon which the ore is transported in boats. 
 
 When the workings of a mine are beginning, when they are still of little depth, and 
 employ few hands, it is sufficient to place over the shaft a simple wheel and axle, by 
 means of which a few men may raise the water pails, and the baskets or tubs filled with 
 ore; but this method becomes soon inadequate, and should be replaced by more power- 
 rul machines. 
 
 ACCESSORY DETAILS. 
 
 Few mines can be penetrated entirely by means of galleries. More usually 
 there are shafts for mounting and descending. In the pits of many mines, the work- 
 men go down and come up by means of the machines which serve to elevate the 
 ores. In several mines of Mexico, and the north of Europe, pieces of wood, fixed 
 on each side of the pit, form the rude steps of a ladder by which the workmen pass up 
 and down. In other mines, steps are cut in the rock or the ore ; as in the quicksilver 
 mines of Idria and the Palatinate, in the salt mines of Wieliczka, and in some of the 
 silver mines of Mexico. In the last they serve for the transport of the ore, which is 
 carried up on men's backs. Lastly, certain mines are entered by means of slopes, some 
 of which have an inclination of more than 30°. The workmen slide down these on a 
 kind of sledge, whose velocity of descent tbey regulate by a cord firmly fixed at the 
 upper end. 
 
 Miners derive light from candles or lamps. They carry the candles in a lump of soft 
 clay, or in a kind of socket terminated by an iron point, which serves to fix it to the 
 rock, or to the timbering. The lamps are made of iron, hermetically closed, and 
 suspended, so that they cannot droop, or invert, and spill the oil. They are usually 
 hung on the thumb by a hook. Miners also employ small lanterns, suspended to their 
 girdles. Many precautions and much experience are requisite to enable them to carry 
 these lights in a current of air, or in a vitiated atmosphere. It is especially in coal 
 mines liable to the disengagement of carburetted hydrogen, that measures of safety are 
 indispensable against the explosions. The appearance of any halo round the flame 
 should be carefully watched as indicating danger; and the lights should be carried near 
 the bottom of the gallery. The great protector against these deplorable accidents, is 
 the safety lamp. See Lamp of Davy. 
 
 We cannot conclude this general outline of the working of mines, without giving 
 some account of the miners. Most men have a horror at the idea of burying them- 
 selves, even for a short period, in these gloomy recesses of the earth. Hence mining 
 operations were at first so much dreaded, that, among the ancients, they were assigned 
 to slaves as the punishment of their crimes. This dislike has diminished with the im- 
 provements made in mining ; and, finally, a profitable and respected species of labour 
 has given mining its proper rank among the other departments of industry. The esprit 
 de corps, so conspicuous among seamen, has also arisen among miners, and has given 
 dignity to their body. Like every society of men engaged in perilous enterprizes, and 
 cherishing the hopes of great success, miners get attached to their profession, talk of it 
 with pride, and eventually in their old age regard other occupations with contempt. 
 They form, in certain countries, such as Germany and Sweden, a body legally consti- 
 tuted, which enjoys considerable privileges. Miners work usually 6 or 8 hours at a 
 time. This period is called a, journey (poste, in French). 
 
 Miners wear, in general, a peculiar dress, the purpose of which is to protect them, as 
 much as possible, from the annoyances caused by water, mud, and sharp stones, which 
 occur in the places where they work. One of the most essential parts of the dress of a 
 German miner is an apron of leather fitted on behind, so as to protect them in sitting 
 on moisture or angular rubbish. In England, the miners wear nothing but flannels ; 
 though they frequently strip off all their clothes, except their trowsers. In many coun- 
 tries the mallet and the pick, or pointerolle (called in German, Scltegel&vA Eisen), disposed 
 in a Saint Andrew's cross, are the badge of miners, and are engraved on their buttons, 
 and on every thing belonging to mines. 
 
 Several of the enterprises executed in mines, or in subserviency to them, merit a 
 distinguished rank among the history of human labours. Several mines are worked to 
 a depth of more than 600 yards, some even to a thousand yards below the surface of the 
 
MINES. 
 
 159 
 
 soil. A great many descend beneath the level of the ocean ; and a few even extend 
 under its billows, and are separated from them by a thin partition of rock, which allows 
 their noise, and the rolling of the pebbles, to be heard. 
 
 In 1792, there was opened, at Valenciana, in Mexico, an octagonal pit, fully 7^ yards 
 wide, destined to have a depth of 560 yards, to occupy 23 years in digging, and to cost 
 240,000/. 
 
 The great drainage gallery of the mines of Clausthal, in the Hartz, is 1 1,377 yards, or 
 C| miles long, and passes upwards of 300 yards below the church of Clausthal. Its 
 excavation lasted from the year 1777 till 1800, and cost about 66,000Z. Several other 
 galleries of efflux might also be adduced, as remarkable for their great length and ex- 
 pense of formation. 
 
 The coal and iron mines subservient to the iron works of Mr. Crawshay, at Merthyr- 
 Tydvil, in Wales, have given birth to the establishment interiorly and above ground, 
 of iron railways, whose total length, many years ago, was upwards of 100 English 
 miles. 
 
 The carriage of the coal extracted from the mines in the neighbourhood of Newcastle 
 to their points of embarkation, is executed almost entirely, both under ground and on 
 the surface, on iron railways, possessing an extent of upwards of 500 miles. 
 
 There is no species of labour which calls for so great a development of power as that 
 of mines ; and accordingly, it may be doubted if man has ever constructed machines so 
 powerful as those which are now employed for the working of some mineral excavations. 
 The waters of several mines of Cornwall are pumped out by means of steam engines, 
 whose force is equivalent, in some instances, to the simultaneous action of many hun- 
 dred horses. 
 
 Mines, General Summary of. 
 
 Mines may be divided into three great classes : 1. Mines in the geological formations 
 anterior to the coal strata; 2. Mines in the secondary formations; 3. Mines in alluvial 
 districts. 
 
 The first are opened, for the most part, upon veins, masses, and metalliferous beds. 
 
 The second, on strata of combustibles, as coal ; and metalliferous or saliferous beds. 
 
 The last, on deposits of metallic ores, disseminated in clays, sands, and other alluvial 
 matters, usually superior to the chalk ; and even of far more recent formation. 
 
 The mines of these three classes, placed, for the most part, in very different physical 
 localities, differ no less relatively to the mode of working them, and their mechanical 
 treatment, than in a geological point of view. 
 
 MINES OF FORMATIONS ANTERIOR TO THE COAL. 
 
 These mines are situated in a few mountainous regions, and their whole amount 
 forms but a small portion of the surface of the earth. The most remarkable of these 
 are : — The Cordilleras of South America ; the mountains of Hungary ; the Altayan 
 mountains ; the Ural mountains ; the Vosges and the Black Forest ; the Harz, and the 
 east of Germany ; the centre of France ; the north of Portugal, and the adjacent 
 portions of Spain ; Britanny ; the corresponding coasts of Great Britain and Ireland; 
 the north of Europe; the Alleghany chain; the south of Spain; the Pyrenees; the 
 Alps; the schistose districts on the banks of the Rhine and the Ardennes; the cal- 
 careous mountains of England and of Daouria. 
 
 MINES OF THE CORDILLERAS OF SOUTH AMERICA. 
 
 Few regions are so celebrated for their mineral wealth as the great chain which, 
 under the name of the Cordillera of the Andes, skirts the shores of the Pacific ocean, 
 from the land of the Patagonians to near the north-west point of the American con- 
 tinent. Who has not heard of the mines of Mexico and Potosi ? The mineral wealth 
 of Peru has passed into a proverb. 
 
 The most important mines of the Cordilleras are those of silver ; but several of gold, 
 mercury, copper, and lead, have likewise been opened. These mountains are not 
 equally metalliferous in their whole extent. The workings occur associated in a small 
 number of districts far distant from each other. 
 
 In the Andes of Chili, particularly in the province of Coquimbo, some silver mines 
 are explored, which afford chiefly ores of an earthy or ferruginous nature, mingled with 
 imperceptible portions of ores with a silver base, known there under the name of Pacos. 
 The same province presents also copper mines of considerable importance, from which 
 are extracted native copper, orange oxide of copper, carbonate of copper (malachite), 
 and copper pyrites, associated with some muriate of copper. In a few mines, masses 
 of native copper of extraordinary magnitude have been found. 
 
 The second metalliferous region of the Andes occurs between the 2 1st and 15th 
 degrees of south latitude. It includes the celebrated mountain of Potosi, situated in 
 
160 
 
 MINES. 
 
 nearly the 20th degree of south latitude, on the eastern slope of the chain, and several 
 other districts likewise very rich, which extend principally towards the north-west, as 
 far as the two banks of the lake Titicaca, and even beyond it, through a total length of 
 nearly 150 leagues. All these districts, which formerly depended on Peru, were 
 united in 1778, to the government of Buenos Ayres. The mines of Potosi were dis- 
 covered in 1545, and have furnished since that period till our days, a body of silver 
 which M. Humboldt values at 230,000,000/. sterling. The first years were the most 
 productive. At that time ores were often found which afforded from 40 to 45 per 
 cent, of silver. Since the beginning of the eighteenth century, the average richness of 
 the ores does not exceed above from 3 to 4 parts in 10,000. These ores are therefore 
 very poor at the present day ; they have diminished in richness in proportion as the 
 excavations have become deeper. But the total product of the mines has not diminished 
 in the same proportion ; abundance of ore having made up for its poverty. Hence, if 
 the mountain of Potosi is not, as formerly, the richest deposit of ore in the world, 
 it may, however, be still placed immediately after the famous vein of Guanaxuato. 
 The ore lies in veins in a primitive clay state, which composes the principal mass of the 
 mountain, and is covered by a bed of clay porphyry. This rock crowns the summit, 
 giving it the form of a basaltic hill. The veins are very numerous ; several, near their 
 outcrop, were almost wholly composed of sulphuret of silver, antimoniated sulphuret 
 of silver, and native silver. Others which offered near the surface merely sulphuret of 
 tin, became richer as they descended. In 1790, seven copper mines were known in 
 the vice-royalty of Buenos Ayres, seven of lead, and two of tin ; the last being merely 
 washings of sands found near the river Oraro. 
 
 On the opposite flank of the chain, in a low, desert plain, entirely destitute of water, 
 which adjoins the harbour of Iquiqua, and forms a part of Peru, occur the silver mines 
 of Huantajaya, celebrated for the immense masses of native silver, which have been 
 sometimes found in them. In 1758, one was discovered weighing eight cwts. 
 
 M. Humboldt quotes 40 cantons of Peru as being at the present day most famous 
 for their subterranean explorations of silver and gold. Those of gold are found in the 
 provinces of Huaailas and Pataz ; the silver is chiefly furnished by the districts of 
 Huantajaya, Pasca, and Chota, which far surpass the others in the abundance of 
 their ores. 
 
 The silver mines of the district of Pasco are situated about 30 or 40 leagues north of 
 Lima, in 10i degrees of south latitude, 4400 yards above the sea-level, on the eastern 
 slope of the Cordilleras, and near the sources of the river Amazons. They were dis- 
 covered in 1G30. These mines, and especially those of Cero of Yauricocha, are actually 
 the richest in all Peru. The ore is an earthy mass of a red colour, containing much 
 iron, mingled with particles of native silver, horn silver, &c, constituting what they call 
 Pacos. At first nothing but these pacos was collected ; and much gray copper and 
 antimoniated sulphuret of silver were thrown among the rubbish. The mean product 
 of all the ores is yJ^; or an ounce and ffc per cwt. ; although some occur which 
 yield 30 or 40 per cent. These rich deposits do not seem to be extended to a great 
 depth; they have not been pursued farther than 130 yards, and in the greater part of 
 the workings only to from 85 to 45. Forty years ago, these mines, which produced nearly 
 2,000,000 of piastres annually, were the worst worked in all South America. The soil 
 seemed as if riddled with an immense number of pits, placed without any order. The 
 drainage of the waters was effected by the manual labour of men, and was extremely 
 expensive. In 1816, some Europeans, among whom were several miners from Corn- 
 wall, mounted several high-pressure steam engines, imported from England, which 
 introduced a considerable improvement in the workings. 
 
 The mines of the province of Chota are situated in about seven degrees of south lati- 
 tude. The principal ones are those of Gualcayoc, near Mecuicampa, discovered in 1771 ; 
 their outcrop occurs at the height of 4500 yards above the sea ; the city of Mecui- 
 campa itself has 4000 yards of elevation, that is, higher than the highest summits of the 
 Pyrenees. The climate is hence very cold and uncomfortable. The ore is a mixture 
 of sulphuret of silver and antimoniated sulphuret, with native silver. It constitutes 
 veins of which the upper portion is formed of pacos, and they sometimes traverse a 
 limestone and sometimes a hornstone, which occurs in subordinate beds. The annual 
 produce of the mines is 67,000 marcs of silver, according to Humboldt. 
 
 In the districts of Huaailas and Pataz, which are at a little distance from the former 
 two, gold mines are worked. This metal is extracted chiefly from the veins of quartz, 
 which run across the primitive schistose mountains. The district of Huaailas contains 
 besides lead mines. Peru possesses, moreover, some mines of copper. 
 
 The quicksilver mine of Huancavelica, the only important mine of this species which 
 has been worked in the New World, occurs on the eastern flank of the Andes of Peru, 
 in 13 degrees of south latitude, at upwards of 6000 yards above the level of the sea. It 
 does not seem referrible to the same class of deposits with the mines hitherto mentioned 
 
MINES. 
 
 161 
 
 Indications of mercurial deposits have been observed in several other points of the Andes 
 of Northern Peru, and of the south of New Granada. 
 
 Lastly, mines of sal-gem are known to exist in Peru, especially near the silver mines 
 of Huantajaya. 
 
 On receding from the district of Chota, the Cordilleras are very indifferently stored 
 with metallic wealth, to the isthmus of Panama, and even far beyond it. The kingdom 
 of New Granada offers but a very small number of silver mines. There are some auri- 
 ferous veins in the province of Antioquia, and in the mountains of Guamoco. The pro- 
 vince of Caracas, the mountains of which may be considered as a ramification of the 
 Cordilleras, presents at Aroa a copper mine which furnishes annually from 700 to 800 
 metric quintals (1400 to 1600 cwt.) of this metal. Finally, we may state in passing, 
 that there is a very abundant salt mine at Zipaquira, in the province of Santa Fe, 
 and that between this point and the province of Santa- F6 -de- Bogota, a stratum of coal 
 occurs at the extraordinary height of 2700 yards. 
 
 Although Mexico presents a great variety of localities of ores, almost the only ones 
 worked are those of silver. Nearly the whole of these mines are situated on the back 
 or the flanks of the Cordilleras, especially to the west of the chain, nearly at the height 
 of the great table land which traverses this region of the globe, or a little below its 
 level in the chains which divide it. They lie in general between 2000 and 3000 yards 
 above the sea ; a very considerable elevation, which is favourable to their prosperity, 
 because in this latitude there exists at that height a mean temperature mild, salubrious, 
 and most propitious to agriculture. There were at the time of Humboldt's visit, from 
 4000 to 5000 deposits of ore exploited. The workings constituted 3000 distinct mines, 
 which were distributed round 500 head quarters or Reales. These mines are not, how- 
 ever, uniformly spread over the whole extent of the Cordilleras. They may be consi- 
 dered as forming eight groups, which altogether do not include a greater space than 
 12,000 square leagues ; viz. hardly more than the tenth part of the surface of Mexico. 
 
 These eight groups are, in proceeding from south to north, 
 
 1. The group of Oaxuaca, situated in the province of this name at the southern extre- 
 mity of Mexico properly so called, towards the 17th degree of north latitude. Besides 
 silver mines, it contains the only veins of gold explored in Mexico. These veins tra- 
 verse gneiss and mica-slate. 
 
 2. The group of Tasco. The most part of the mines which compose it are situated 
 20 or 25 leagues to the south west of Mexico, towards the western slope of the great 
 plateau. 
 
 3. The group of Biscania, about 20 leagues north east of Mexico. It is of moderate 
 extent, but it couiprehends the rich workings of Pachuca, Real del Monte, and Moram. 
 The district of Real del Monte contains only a single principal vein, named Veta Bezi- 
 cana of Real del Monte, in which there are several workings ; it is, however, reckoned 
 among the richest of Mexico. 
 
 4. The group of Zimapan. It is very near the preceding, about 40 leagues north 
 west of Mexico, towards the eastern slope of the plateau. Besides numerous silver mines, 
 it includes abundant deposits of lead, and some mines of yellow sulphuret of arsenic. 
 
 5. The Central group, of which the principal point is Guanaxuato, a city of 70,000 in- 
 habitants, placed at its southern extremity, and 60 leagues N. N. W. of Mexico. It 
 comprises among others the famous mine districts of Guanaxuato, Catorce, Zacatecas, 
 Sombrerete • the richest in Mexico, and which alone furnish more than half of all the 
 silver which this kingdom brings into circulation. 
 
 The district of Guanaxuato presents only one main vein, called the Veta Madre. This 
 vein is enclosed principally in clay-state, to whose beds it runs parallel, but occa- 
 sionally it issues out of them to intersect more modern rocks. The vein is composed 
 of quartz, carbonate of lime, fragments of clay slate, &c. ; and includes the sulphurets of 
 iron, of lead, and of zinc in great quantities, some native silver, sulphuret of silver, and 
 red silver ; its power (thickness of the vein) is from 43 to 48 yards. It is recognised 
 and worked throughout a length of upwards of 13,000 yards ; and contains 19 exploit- 
 ations, which produced annually well on to 1,200,0007. in silver. One of the explora- 
 tions, that of Valenciana, produces 320,000/. ; being equal to about one- fifteenth of the 
 total product of the 3000 mines of Mexico. Since 1764, the period of its discovery, its 
 neat annual product has never been less than from two to three millions of francs 
 (80,000/. to 120,000/.); and its proprietors, at first men of little fortune, became, in 
 ten years, the richest individuals in Mexico, and perhaps in the whole globe. 
 
 The workings of this mine are very extensive, and penetrate to a depth of 550 yards. 
 They employ a great many labourers. 
 
 The district of Zacatecas presents in like manner only a single vein in greywacke ; 
 which, however, is the seat of several workings. 
 
 The deposits mined at Catorce are in limestone ; the mine called Purissima de Ca- 
 torce has been explored to about 650 yards in depth; and yielded, in 1796, nearly 
 220,000/. There are also mines of antimony in the district of Catorce. 
 
 Y 
 
1G2 
 
 MINES. 
 
 Towards the western part of the group of which we are now speaking, copper mines 
 are worked in the provinces of Valladolid and Guadalaxara ; the ores being chiefly com- 
 posed of protoxide of copper (orange copper), sulphuret of copper, and native copper. 
 These mines produce about 2000 metric quintals of copper annually (440,000lbs. Eng. 
 lishj. In the same district, ores of tin are collected in the alluvial soils, particularty 
 near Mount Gigante. The concretionary oxide of tin, so rare in Europe, is here the 
 most common variety. This metal occurs also in veins. 
 
 The central part of Mexico contains many indications of sulpnuret of mercury (cin- 
 nabar) ; but in 1804 it was worked only in two places, and to an inconsiderable extent. 
 
 6. The group of new Gallicia is situated in the province of this name, about 100 leagues 
 N.W. from Mexico. It comprises the mines of Balanos, one of the richest districts. 
 
 7. The group of Durango and Sonora, in the intendancies of the same name. It is 
 very extensive. The mines are situated in part on the table land, and in part on the 
 western slope. Durango is 140 leagues N. N. W. of Mexico. 
 
 8. The group of Chinuahua. It takes its name from the town of Chinuahua, situated 
 100 leagues N. of Durango. It is exceedingly extensive, but of little value; and ter- 
 minates at 29° 10' of north latitude. 
 
 Mexico possesses, besides, several mines which are not included in the eight preceding 
 groups. Thus the new kingdom of Leon, and the province of New Saint- Ander, present 
 abundant mines of lead. New Mexico contains copper mines and many others. 
 
 Lastly, rock salt is mined in several points of New Spain ; and coal seems to occur in 
 New Mexico. 
 
 The richness of the different districts of the silver mines or reales is extremely unequal. 
 Nineteen twentieths of these reales do not furnish altogether more than one-twelfth of 
 the total product. This inequality is owing to the excessive richness of some deposits. 
 The ores of Mexico are principally veins; beds and masses are rare. The veins traverse 
 chiefly, and perhaps only primitive and transition rocks, among which certain porphyries 
 are remarked as very rich in deposits of gold and silver. The silver ores are mostly 
 sulphuret of silver, black antimoniated sulphuret of silver, muriate of silver (hornsilver), 
 and gray copper. Many explorations are carried on in certain earthy ores, called 
 collorados, similar to the pacos of Peru. Lastly, there are ores of other metals, which 
 are worked principally, and sometimes exclusively, for the silver which they contain; 
 such are the argentiferous sulphuret of lead, argentiferous sulphuret of copper, and 
 argentiferous sulphuret of iron. 
 
 Ores of very great richness occur in Mexico ; but the average is only from 3 to 4 
 ounces per ewt., or from 18 to 25 in 10,000. There are some, indeed, whose estimate 
 does not exceed 2\ ounces. Almost all the argentiferous veins afford a little gold ; the 
 silver of Guanaxuato, for example, contains The enormous product of the Mexican 
 
 mines is to be ascribed rather to the great facility of working them, and the abundance 
 of ores, than to their intrinsic richness. 
 
 The art of mining was little advanced in this country at the period of Humboldt's 
 journey ; the workings presented a combination of small mines, each of which had only 
 one aperture above, without any lateral communications between the different shafts. 
 
 The form of these explorations was too irregular to admit of their being called workings 
 by steps. The shafts and the galleries were much too wide. The interior transport of 
 the ores is generally effected on the back of men ; rarely by mules. The machines for 
 raising the ore and drawing off the water are in general ill combined ; and the horse 
 gigs for setting them in motion ill constructed. The timbering of the shafts is very 
 imperfectly executed ; the walled portions alone are well done. There are some galleries 
 of drainage, but they are too few, and ill directed. Latterly, English capitalists and 
 miners have formed companies for working the silver mines of Mexico ; which will pro- 
 bably produce in time a happy revolution. 
 
 The silver ores of Spanish America are treated partly by fusion, and partly by amal- 
 gamation, but more frequently by the latter mode; hence the importation of mercury 
 forms there an object of the highest importance, especially since the quicksilver mine of 
 Huancavelica fell in, and ceased to be worked. This mine is the only one in Spanish 
 America which belongs to the government. For the modern state of these mines, see 
 Silver. 
 
 The following table shews, according to M. de Humboldt, what was the annual pro- 
 duct of the silver mines of South America, at the beginning of this century. It is 
 founded in a great measure, upon official documents : — 
 
 Mexico - - - 2,196,140 marcs, or 537,512 kil., worth £4,778,000 
 Peru - - 573,958 140,478 1,250,000 
 
 Buenos- Ayres - - 463,098 110,764 984,600 
 
 Chili - - 25,957 6,827 060,680 
 
 Total - 3,259,153 795,581 7,073,280 
 
MINES. 
 
 163 
 
 To complete our picture of the mineral wealth of Spanish America, it remains to 
 speak of its principal gold mines ; but these belong to a geological locality, alluvial sand 
 and gravel, very different from that of our present objects. The most important of these 
 gold sands are washed on the western slope of the Cordilleras; viz. in New Granada, 
 from the province of Barbacoas, to the isthmus of Panama, to Chili, and even to the 
 shores of the seas of California. There are likewise some on the eastern slope of the 
 Cordilleras, in the high valley of the river Amazons. The washings of New Granada 
 produce also some platina. 
 
 The mines, properly so called, and the washings of South America, furnish, altogether, 
 42,575 marcs, or 10,418 kilogrammes (22,920 libs. Eng.) of gold, worth 1, 435,7 20<?. 
 
 MINES OF HUNGARY. 
 
 The metallic mines of this kingdom, including those of Transylvania, and the Bannat 
 of Temeschwar, form four principal groups, which we shall denote by the group of the 
 N. W., group of the N. E., group of the # E., and group of the S. E. 
 
 The group of the N. W. embraces the districts of Schemnitz. Kremnitz, Kcenigsberg, 
 Neuhsohl, and the environs of Schmoelnitz, Bethler, Rosenau, &c. 
 
 Schemnitz, a royal free city of mines, and the principal centre of the mines of Hun- 
 gary, lies 25 leagues to the north of Buda, 560 yards above the sea, in the midst of a 
 small group of mountains covered with forests. The most part of these mountains, the 
 highest of which reaches an elevation of 1130 yards above the ocean, are formed of 
 barren trachytes (rough trap rocks) ; but at their foot below the trachytic formation, 
 a formation is observed consisting of green-stone porphyries, connected with syenites, 
 passing into granite and gneiss, and including subordinate beds of mica-slate and lime- 
 stone. It is in this formation that all the mines occur. 
 
 It has been long known that the greenstone porphyries of Schemnitz. have intimate 
 relations with the metalliferous porphyries of South America. M. Beudant, on com- 
 paring them with those brought by M. de Humboldt from Guanaxuato, Real del Monte, 
 &c.,has recognised an identity in the minutest details of colour, structure, composition, 
 respective situation of the different varieties, and even in the empirical character of 
 efferveseence with acids. The metalliferous rocks appear at Schemnitz only in a space 
 of small extent, comprehended partly in a small basin, of which the city occupies the 
 south border. They are traversed by veins which, for the most part, cut across the stra- 
 tification, but which also are sometimes obviously parallel to it. These veins are in 
 general very powerful ; their thickness amounting even to more than 40 yards, but their 
 extent in length seems to be usually inconsiderable. They are numerous and parallel 
 to each other. It appears that they have no side plates of vein stones (sullebundes), but 
 that the metalliferous mass reposes immediately on the cheeks or sections of the rock, 
 which is usually more or less altered, and includes always much pyrites near the point 
 of contact, and even to a distance of several feet. The substances which constitute the 
 body of these veins, are drusy quartz, carious quartz, ferriferous carbonate of lime, and 
 sulphate of barytes, with which occur sulphuret of silver mixed with native silver 
 containing more or less gold, which is rarely in visible scales ; sulphuret of silver, argen- 
 tiferous galena, blende, copper and iron pyrites, &c. The sulphuret of silver and the 
 galena are the two most important ores. Sometimes these two substances are insulated, 
 sometimes they are mixed in different manners so as to furnish ores of every degree of 
 richness, from such as yield 60 per cent, of silver down to the poorest galena. The gold 
 seldom occurs alone; it generally accompanies the silver in a very variable proportion, 
 which most usually approaches to that of 1 to 30. 
 
 The ores of Schemnitz are all treated by fusion; the poor galenas at the smelting 
 house of Schemnitz (bleyhutte\ and the resulting lead is sent as working lead to the 
 smelting houses of Kremnitz, Neusohl, and Schernowitz, whither all the silver ores 
 prepared in the different spots of the country are transported in order to be smelted 
 
 The mines of Schemnitz, opened 800 years ago, have been worked to a depth of more 
 than 350 yards. The explorations are in general well conducted. Excellent galleries 
 of efflux have been excavated ; the waters for impulsion are collected and applied 
 with skill. It may be remarked, however, that these mines begin to decline from the 
 state of prosperity in which they stood several years ago ; a circumstance to be ascribed 
 probably to the same pains being no longer bestowed on the instruction of the officers 
 appointed to superintend them. Maria Theresa established in 1760, at Schemnitz, a 
 school of mines. This acquired at its origin, throughout Europe, a great celebrity, 
 which it has not been able to maintain. 
 
 Kremnitz lies about 5 leagues N. N. W. of Schemnitz, in a valley flanked on the 
 right by a range of hills formed of rocks quite analogous to the metalliferous rocks of 
 Schemnitz. In the midst of these rocks, veins are worked nearly similar to those of 
 Schemnitz ; but the quartz which forms their principal mass is more abundant, and con- 
 tains more native gold. Here also are found sulphuret and hydrosulphuret of antimony, 
 
164 
 
 MINES, 
 
 which do not occur at Schemnitz. The metalliferous district is of very moderate extent, 
 and is surrounded by the trachytic district which overlies it, forming to the East and 
 West considerable mountains. 
 
 The city of Kremnitz is one of the most ancient free royal cities of mines in Hun- 
 gary, It is said that mines were worked there even in the times of the Romans ; but 
 it is the Germans who, since the middle ages, have given a great development to these 
 exploitations. There exists at Kremnitz a Mint-office, to which all the gold and silver 
 of the mines of Hungary are carried in order to be parted, and where all the chemical 
 processes, such as the fabrication of acids, &c, are carried on in the large way. 
 
 About 6 leagues N. N. E. from Schemnitz, on the banks of the Gran, lies the little 
 village of Neusohl, founded by a colony of Saxon miners. The mountains surrounding 
 it include mines very different from those of which we have been treating. At Herren- 
 grand, 2 leagues from Neusohl, greywacke forms pretty lofty mountains ; this rock is 
 covered by transition limestone, and is supported by mica slate. The lower beds con- 
 tain bands of copper ores, chiefly copper pyrites. The mica-slate includes likewise 
 masses of ore, apparently constituting veins in it. These ores have been worked since 
 the 13th century. The copper extracted contains in a hundred weight 6 ounces of 
 silver. 
 
 Eighteen or twenty leagues to the east of Neusohl, we meet with a country very rich 
 in iron and copper mines, situated chiefly in the neighbourhood of Bethler, Schmcelnitz, 
 Einsiedael, Rosenau, &c. Talcose and clay slates form the principal body of the moun- 
 tains here, along with hornblende rocks. The ores occur most usually in strata. Those 
 of iron, are sparry ore, and especially hydrate of iron, compact and in concretions, ac- 
 companied with specular iron ore. They give employment to a great many large 
 smelting houses. The county of Goemar alone contains 22 works ; and that of Zips 
 also a great number. The copper mines lie chiefly in the neighbourhood of Schmoelnitz 
 and Goelnitz. The copper extracted contains about 6 or 7 ounces of silver in the hun- 
 dred weight. Near Zalathna there is a quicksilver mine nearly inactive ; and near 
 Rosenau one of antimony. 
 
 To conclude our enumeration of the mineral wealth of this country, it remains merely 
 to state that there are opal mines in the environs of Czervenitza, placed in the trachytic 
 conglomerate. 
 
 GROUP OF THE NORTH EAST, OR OF NAGABANVA. 
 
 The mines of this group lie in a somewhat considerable chain of mountains, which, 
 proceeding from the frontiers of Buchowina, where it is united to the Carpathians, finally 
 disappears amidst the saliferous sandstones between the Theiss, Lapos, and Nagy Szamos, 
 on the northern frontiers of Transylvania. These mountains are partly composed of 
 rocks analogous to those of Schemnitz, traversed by veins which have much resemblance 
 to the veins of this celebrated spot. Into these veins a great many mines have been 
 opened, the most important of which are those of Nagabanya, Kapnick, Felsobanya, 
 Miszbanya, Laposbanya, Olaposbanya, Ohlalapos. All these mines produce gold. Those 
 of Laposbanya furnish, likewise, argentiferous galena ; those of Olaposbanya contain 
 copper and iron ; and those of Kapnick copper. Realgar occurs in the mines of Felso- 
 banya ; and orpiment in those of Ohlalapos. Several of them produce manganese and 
 sulphuret of antimony. Lastly, towards the north, in the county of Marmarosh, lies 
 the important iron mine of Borscha, and on the frontiers of Buchowina the lead mine 
 of Radna, in which also much zinc ore occurs. 
 
 The ?nines composing the group of the East, or of Abrudbanya, occur almost all in the 
 mountains which rise in the western part of Transylvania, between Lapos and Maros, in 
 the environs of Abrudbanya. M. Beudant notices in this region, limestones, sandstones, 
 trachytes, basalts, and sienite porphyries, apparently quite analogous to the greenstone 
 porphyries of Schemnitz. It seems to be principally in the latter rocks that the mines 
 forming the wealth of this country occur ; but some of them exist also in the mica- 
 slate, the greywacke, and even in the limestone. The principal mines are at Nagyag, 
 Korosbanya, Vorospatak, Boitza, Csertesch, Fatzbay, Almas, Porkura, Butschum, and 
 Stonischa. There are, in all, 40 exploitations ; the whole of which produce auriferous 
 ores smelted at the foundry of Zalathna. These mines contain also copper, antimony, 
 and manganese. They are celebrated for their tellurium ore, which was peculiar to them 
 prior to the discovery of this metal a few years back in Norway. The auriferous de- 
 posits contained in the greenstone porphyry are often very irregular. The mines of 
 Nagyag are the richest and best worked. The numerous veins occur partly in the 
 sienite porphyry, and partly in the greywacke. The auriferous ore is accompanied with 
 galena, realgar, manganese, iron, and zinc. There are iron mines in great beds near 
 Vayda-Huniad and Gyalar. Some cobalt mines are also noticed. 
 
 The group of the S. E., or of the Bannat of Temeschwar, occurs in the mountains which 
 block up the valley of the Danube at Orschova, through a narrow gorge of which the 
 river escapes. The principal mines are at Oravitza, Moldawa, Szaska, and Dognaaczka. 
 
MINES. 
 
 165 
 
 They produce chiefly argentiferous copper, yielding a marc of silver (nearly i pound) 
 in the hundred weight, with occasionally a little gold. Ores of lead, zinc, and iron, 
 are also met with. The mines are famous for their beautiful specimens of blue car- 
 bonate of copper, and various other minerals. The mine of Moldawa affords likewise 
 orpiment. These metallic deposits lie in heels and veins ; the former occurring parti- 
 cularly between the mica-slate and the limestone, or sometimes between the limestone 
 and the sienite porphyry. Well defined veins also are known to exist in the sienite 
 and the mica-slate. The Bannat possesses moreover important iron-mines at Dom- 
 brawa and Ruchersberg ; near Dombrawa sulphuret of mercury is found. Cobalt 
 mines occur likewise in these regions. 
 
 The mines constituting the four groups now described are not the sole metallic 
 mines possessed by Hungary. A few others, but generally of little importance, are 
 scattered over different parts of this kingdom. Several have been noticed in the 
 portion of the Carpathians which separates Transylvania from Moldavia and Wallachia. 
 Their principal object is the exploration of some singular deposits of galena. 
 
 Besides the mines just noticed, Hungary contains some coal mines, numerous mines 
 of rock-salt, and several deposits of golden sands situated chiefly on the banks of the 
 Danube, the Marosch, and the Nera. 
 
 The mines of the kingdom of Hungary produce annually, according to M. Heron de 
 Villefosse, 5218 marcs, or 2810 pounds English of gold, worth 175,976/. ; and about 
 85,000 marcs, or 45,767 pounds of silver, worth 186,132/. The mines of Transylvania 
 furnish nearly the half of the whole quantity of gold, and one seventeenth of the silver 
 now stated. The other mines of Europe produce together nearly twice as much silver, 
 but merely a few marcs of gold. Hungary affords besides from 18 to 20 thousand 
 metric quintals (about 4,000,000 libs. Eng. ) of copper annually, and a great deal of 
 iron. 
 
 From these mines proceed likewise from 3000 to 4000 metric quintals (660,000 to 
 880,000 libs. E. ) of lead ; a quantity not more than is needed by the refining-houses 
 for the ores of silver and gold. 
 
 MINES OF THE ALTAYAN MOUNTAINS. 
 
 At the western extremity of the chain of the Altayan mountains, which separate 
 Siberia from Chinese Tartary, there exists a number of metalliferous veins, in which 
 several important workings have been established since the year 1742. They con- 
 stitute the locality of the mines of Koly wan ; the richest in the precious metals of 
 the three districts of this kind existing in Siberia. 
 
 These mines are opened up in the schistose formations which surround to the N. and 
 W. and to the S. W. the western declivity of the high granitic chain, from which they are 
 separated by formations consisting of other primitive rocks. These schists alternate in 
 some points with quartzose rocks, called by M. Renovantz hornstone, and with lime- 
 stone. They are covered by a limestone, replete with ammonites. The metalliferous 
 region forms a semicircle, of which the first lofty mountains occupy the centre. 
 
 The most important exploration of this country is the silver mine of Zmeof, or 
 Zmeinogarsk, in German Schlangenberg, situated to the N. W. of the high mountains 
 in 51° 9' 25" N. L. and 79° 49' 50" long, east of Paris. It is opened on a great 
 vein, which contains argentiferous native gold, auriferous native silver, sulphuret of 
 silver, hornsilver, gray copper, sulphuret of copper, green and blue carbonated copper, 
 red oxide of copper, copper pyrites, sulphuret of lead, and great masses of testaceous 
 arsenic slightly argentiferous. There occur likewise sulphuret of zinc, iron pyrites, 
 and sometimes arsenical pyrites. The gangues (vein stones) of these different ores are 
 sulphate of baryta, carbonate of lime, quartz, but rarely fluate of lime. The principal 
 vein, which is of great power, has been traced through a length of several hundred 
 fathoms, and to a depth of no less than 96 fathoms. In its superior portion, it has an 
 inclination of about 50 degrees ; but lower down it becomes nearly vertical. Its roof 
 is always formed of clay-slate. On the floor of the vein, the slate alternates with horn- 
 stone. This vein pushes out branches in several directions ; it is intersected by barren 
 veins, and presents successive stages of different richness. The first years were the 
 most productive. The German miners employed subsequently by the Russian govern- 
 ment have introduced regularity into the workings ; and have excavated a gallery of 
 efflux 585 fathoms long. 
 
 The most important of the other silver mines of this department are those of Tchere- 
 panofski, 3 leagues S. E. of Zmeof; those of Smenofski, 10 leagues S. E. ; those of 
 Nicolaiski, 20 leagues to the S. S. W. ; and of Philipofski, 90 leagues S. E. of the 
 same place. The last mine lies on the extreme frontier of Chinese Tartary. It is not 
 known whether the southern slope of the Altaic chain within the Chinese territories, 
 contains metalliferous deposits. 
 
 The ores extracted from these different mines yield on an average per quintal an 
 
166 
 
 MINES. 
 
 ounce of silver, which contains 3 per cent, of gold. Their annual product was towards 
 1786, according to M. Patrin, 3000 marcs, or 1615 libs, avoirdupois of gold, worth 
 101,151/. ; and 60,000 marcs, or 31,020 libs, avoird. of silver, worth 130,520/. 
 
 The precious metals are not the sole product of this mineral district. There is an 
 important copper-mine 15 leagues N. W. of Zm^of, in a chain of hills formed of gra- 
 nitic rocks, schists, porphyries, and shell-limestone, graduating into the plain. The 
 vein presents copper pyrites, sulphuret of copper, and native copper, disseminated in 
 argillaceous substances, more or less ferruginous, and of different degrees of hardness. 
 This mine, which bears the name of Aleiski-Loktefski, furnished annually at the date 
 of 1782, 1500 quintals (metric), or 330,000 libs, avoird. of copper, which was coined 
 into money in the country itself. 
 
 At Tchakirskoy, on the banks of the Tscharisch, towards the northern extremity of 
 the metalliferous semicircle, mentioned above, there is a mine of argentiferous copper 
 and lead, opened in a very large but extremely short vein. Besides the lead and 
 copper ores, including a little silver, this mine affords a great quantity of calamine 
 (carbonate of zinc), which forms occasionally fine stalactites of a white or green colour. 
 
 The northern flank of the Altai mountains presents few mines. Some veins of 
 copper exist 2000 leagues east of Zmeof, near the spot where the river Janissei issues 
 from the Sa'ianean mountains, which are a prolongation of the Altayan chain. 
 
 There is no lead-mine, properly so called, in the Altai mountains. Almost all the 
 lead which is required for the treatment of the silver and gold ores is obtained from the 
 department of Nertchinsk, situated 700 leagues off, on the borders of the river Amour. 
 
 The first smelting-house erected in this district was in the middle of the metalliferous 
 region at Kolywan, the place from which it takes its name. It has been suppressed on 
 account of the dearth of wood in the neighbourhood of the mines. The principal exist- 
 ing foundry is that of Bornaoul on the Ob, 50 leagues north of Zmeof. 
 
 MINES OF THE URAL MOUNTAINS. 
 
 This chain of mountains, which begins on the coasts of the icy sea, and terminates 
 in the 50th degree of latitude amidst the steppes of the Kerguis, after having formed, 
 through an extent of more than 40 leagues, the natural limit between Europe and 
 Asia, contains very rich and very remarkable deposits of metallic ores, which have 
 given rise to important mines of iron, copper, and gold. These explorations are 
 situated on the two slopes, but chiefly on the one that looks to Asia, from the environs 
 of Ekaterinbourg to about 120 or 130 leagues north of that city. They constitute the 
 department of the mines of Ekaterinbourg, one of the three belonging to Siberia. 
 
 The copper-mines are pretty numerous, and lie almost wholly on the oriental slope 
 of the chain. They are opened into veins of a very peculiar nature, and which 
 although very powerful at the surface, do not extend to any considerable depth. These 
 veins are in general filled with argillaceous matters, penetrated with red oxide of copper, 
 and mingled with green and blue carbonated copper, sulphuret of copper, and native 
 copper. The most important workings are those of Tourinski and Gonmechafski. 
 
 The first are situated 120 leagues north of Ekaterinbourg, towards the 60th degree 
 of N. latitude, at the eastern base of the Uralian mountains, near the banks of the Touria. 
 They amount to three, opened in the same vein, which turns round an angle presented 
 by the chain in this place. The ground is composed of a porphyry with a hornstone 
 basis, of clay-slate, and of a white or grayish limestone, which form the roof and floor 
 of the vein. The ore yields from 18 to 20 per cent., and these mines produced annu- 
 ally in 1786, 10,000 metric quintals (2,200,000 libs avoird.) of copper. 
 
 The mivfe of Goumechefski lies 12 or 15 leagues S. W. of Ekaterinbourg, near a 
 lake bordered by primitive mountains, which form in this region the axis of the chain 
 of the Urals. This mine is celebrated for the beautiful malachites that occur in it. 
 It has furnished almost all the fine specimens of this substance employed in jewellery. 
 The vein, of which the sides are calcareous, is vertical, and runs north and south. 
 It does not sink deeper than about 50 yards, and is filled with a species of coarse 
 pudding-stone, composed of masses of primitive rocks. The ore yields from 3 to 4 
 per cent, of copper, and the mine furnished about the year 1786, 4,400,000 libs, avoird. 
 of this metal per annum. 
 
 The beds of iron ore occur generally at a certain distance from the axis of the 
 central chain. Those of the western slope lie sometimes in a gray compact limestone, 
 which contains entrochi and other petrifactions, and whose geological age has not been 
 ascertained, but it appears to be much mere modern than the rocks of the central chain. 
 Both the one and the other seem to form large veins, which extend little in depth, or 
 rather fill irregular and shallow cavities. The most common ore is the hydrate of iron 
 (bog ore), hematite, or compact iron ore, sometimes mixed or accompanied with 
 hydrate of manganese, and occasionally with ores of zinc, copper, and lend. Black oxide 
 of iron, possessing magnetic polarity, likewise frequently occurs, particularly in the 
 
MINES. 
 
 1G7 
 
 mines of the eastern slope, on which, in fact, entire mountains of loadstone repose. All 
 these ores, mixed with a greater or less quantity of clay differently coloured, are 
 worked by open quarries, and most usually without using gunpowder, or even iron 
 wedges. They yield rarely less than .50 or 60 per cent., and keep in action numerous 
 smelting- houses situated on the two flanks of the chain ; the oldest of them have been 
 established since 1628, but the greater number date only from the middle of the 18th 
 century. The most celebrated mines are those of Balgodat and Kcskanar, situated on the 
 eastern slope from 30 to 50 leagues north of Ekaterinbourg. In the foundries of the 
 eastern slope, anchors, cannons, bullets, &c. are fabricated; and in the whole a con- 
 siderable quantity of bar iron. The products of the -works on the western side are 
 directly embarked on the different feeders of the Volga, from which they are at no 
 great distance. Those of the eastern slope are transported during winter on sledges to 
 the same feeder streams, after crossing the least elevated passages of the Urals. 
 
 The quantity of materials fabricated by the iron works of both slopes, amounted 
 annually, towards the year 1790, to .more than 11,000,000 libs, avoird. This country 
 is peculiarly favoured by nature for this species of industry; for vast deposits of excel- 
 lent iron ores occur surrounded by immense forests of firs, pines, and birches ; woods, 
 whose charcoal is excellently adapted to the fabrication of iron. 
 
 The copper-mines of the Uralian mountains, and the greater part of the iron mines 
 and foundries, form a portion of the properties of some individuals, who may be 
 instanced as among the richest in Europe. The Russian government has neglected no 
 opportunity of promoting these enter prizes. It has established at Tourinsky a con- 
 siderable colony, and at Irbitz a fair which has become celebrated. 
 
 There is only one gold mine in the Ural mountains, that of Beresof, situated three 
 leagues N. E. of Ekaterinbourg, at the foot of the Urals, on the Asiatic side. It is 
 famous for the chromate of lead, or red lead ore, discovered there in 1776, and worked 
 in the following years, as also for some rare varieties of minerals. The ore of Beresof 
 is a cavernous hydrate of iron (bog ore), presenting here and there some small striated 
 cubes of hepatic iron, and occasionally some pyrites. It contains 5 parts of native 
 gold in 100,000. This deposit appears to have a great analogy with the deposits of 
 iron ore of the same region. It constitutes a large vein, running from N. to S., 
 encased in a formation of^gneiss, hornblende schists, and serpentine, and which does not 
 appear to dip to any considerable depth. It becomes poor in proportion to its distance 
 from the surface. The exploitation, which is in the open air, has dug down 25 yards ; 
 having been carried on since the year 1726. The gold is extracted from the ore by 
 stamping and washing. In 1786, 500 marcs were collected; but the preceding years 
 had furnished only 200, because they then worked further from the surface. German 
 miners were called in to direct the operations. On some points of the Ural mountains, 
 and the neighbouring countries, deposits of an auriferous clay have been noticed ; but 
 they have not hitherto been worked. 
 
 Beds of chromate of iron have also been discovered in these mountains. 
 The beautiful plates of mica, well known in mineral cabinets, and even in commerce, 
 under the name of Muscovy talc, or Russian mica, come from the Urals. There are 
 explorations for them near the lake Tschebarkoul, on the eastern flank of this chain. 
 From the same canton there is exported a very white clay, apparently a kaolin. 
 
 25 leagues north of Ekaterinbourg, near the town of Mourzinsk, there occur in a 
 graphic granite, numerous veins, containing amethysts, several varieties of beryl, eme- 
 ralds, topazes, &c. 
 
 Table of the production of the Russian Mines during the years 1830, 18*31, 1 S32, 
 1833, and 1834 ; by M. Teploff, one of their Officers. 
 
 Substances. 
 
 1830. 
 
 1831. 
 
 1832. 
 
 1833. 
 
 1834. 
 
 
 kil. 
 
 kil. 
 
 kil. 
 
 kil. 
 
 kil. 
 
 Gold - 
 
 6,260 
 
 6,582 
 
 6,916 
 
 6,706 
 
 6,626 
 
 Platinum 
 
 1,742 
 
 1,767 
 
 1,907 
 
 1,919 
 
 1,695 
 
 Auriferous silver 
 
 20,974 
 
 21,563 
 
 21,454 
 
 20,552 
 
 20,666 
 
 
 
 
 
 (3) 
 
 
 Copper - 
 
 8,860,696 
 
 3,904,533 
 
 3,620,201 
 
 3,387,252 
 
 ? 
 
 Lead 
 
 698,478 
 
 792,935 
 
 688,351 
 
 716,500 
 
 ? 
 
 
 
 
 
 (*) 
 
 
 Cast iron 
 
 182,721,274 
 
 180,043,730 
 
 162,480,224 
 
 159,118,372 
 
 ? 
 
 
 
 (2) 
 
 
 
 
 Salt - 
 
 342,240,893 
 
 282,821,358 
 
 372,776,283 
 
 491,862,299 
 
 ? 
 
 Coal 
 
 7,863,642 
 
 9,774,998 
 
 6,596,034 
 
 8,227,528 
 
 ■3 
 
 Naphtha 
 
 4,253,000 
 
 4.253,000 
 
 4,253,000 
 
 4,253,000 
 
 
168 
 
 MINES. 
 
 MINES OF THE VOSGES AND THE BLACK FOREST. 
 
 These mountains contain several centres of exploration of argentiferous ores of le&d 
 and copper, iron ores, and some mines of manganese and anthracite. 
 
 At the Croix-aux-mines, department of the Vosges, a vein of argentiferous lead has 
 been worked, which next to the veins of Spanish America, is one of the greatest known. 
 It is several fathoms thick, and has been traced and mined through an extent of more 
 than a league. It is partly filled with debris, among which occurs some argentiferous 
 galena. It contains also phosphate of lead, antimoniated sulphuret of silver, &c. 
 It runs from N. to S. nearly parallel to the line of junction of the gneiss, and a por- 
 phyroid granite, that passes into sienite and porphyry. In several points it cuts across 
 the gneiss; but it probably occurs also between the two rocks. It has never been worked 
 below the level of the adjoining valley. The mines opened on this vein produced, it 
 is said, at the end of the 16th century, 26,0001. per annum; they were still very pro- 
 ductive in the middle of the last century, and furnished, in 1756, 2,640,000 lbs. 
 avoird. of lead, and 6000 marcs, or 3230 pounds avoird. of silver. 
 
 The veins explored at Sainte Marie of the mines, also traverse the gneiss ; but their 
 direction is nearly perpendicular to that of the vein of the Croix, from which they are 
 separated by a barren mountain of sienite. They contain besides galena, several ores 
 of copper, cobalt, and arsenic ; all more or less argentiferous. There is found also at a 
 little distance from Saint Mary of the mines, a vein of sulphuret of antimony The 
 mines of Sainte Marie, opened several centuries ago, are among the most antient in 
 France ; and yet they have been worked only down to the level of the adjoining 
 valleys. 
 
 There has been opened up in the environs of Giromagny, on the southern verge of the 
 Vosges, a great number of veins, containing principally argentiferous ores of lead and 
 copper. They run nearly from N. to S., and traverse porphyries and clay-slates; 
 a system which has some analogy with the metalliferous district of Schemnitz. The 
 workings have been pushed so far as 440 yards below the surface. These mines were 
 in a flourishing state in the 14th and 16th centuries; and became so once more at the 
 beginning of the 17th, when they were undertaken by the house of Mazarin. In 1743 
 they still produced 100 marcs, fully 52 libs, avoird. of silver in the month. 
 
 The mines of la Croix, of Sainte- Marie- aux- mines, and of Giromagny, are now 
 abandoned ; but it is hoped that those of the first two localities will be resumed ere 
 long. 
 
 In the mountains of the Black Forest, separated from the Vosges by the valley of the 
 Rhine, but composed of the same rocks, there occur at Badenweiler and near Hochbergi 
 not far from Freyburg, workings of lead in great activity. These form six distinct 
 mines, and annually afford 88,000 libs, avoird. of lead, and 200 marcs of silver. In the 
 Furstenberg near Wolfach, particularly at Wittichen, there are mines of copper, cobalt, 
 and silver. The mines of Wittichen produced, some years ago, 1600 marcs, or near 
 880 libs, avoird. of silver per annum. They supply a manufactory of smalt, and one of 
 arsenical products. A few other inconsiderable mines of the same kind exist in the 
 grand duchy of Baden, and in the kingdom of Wurtemberg. 
 
 Several important iron mines are explored in the Vosges ; the principal are those of 
 Framont, in the department of the Vosges, whose ores are red oxide of iron and brown 
 hematite, which appear to form veins of great thickness, much ramified, and very 
 irregular, in a district composed of greenstone, limestone and greywacke. The sub- 
 terranean workings, opened on these deposits, have been hitherto very irregular. There 
 has been discovered lately in these mines, an extremely rich vein of sulphuret of copper. 
 At Rothau, a little to the east of Framont, thin veins of red oxide of iron are worked ; 
 sometimes magnetic, owing probably to an admixture of protoxide of iron. These veins 
 run through a granite, that passes into sienite. At Saulnot near Belfort, there are 
 iron mines, analogous to those of Framont. 
 
 In the neighbourhood of Ihann and Massovaux, near the sources of the Moselle, veins 
 are worked of an iron ore, that traverse formations of greywacke, clay-slate, and por- 
 phyry. Lastly, in the north of the Vosges, near Bergzabern, Erelenbach, and Schenau, 
 several mines have been opened on very powerful veins of brown hematite and compact 
 bog ore, accompanied with a little calamine, and a great deal of sand and debris. In 
 some points of these veins, the iron ore is replaced by various ores of lead, the most 
 abundant being the phosphate, which are explored at Erlenbach and Katzenthal. These 
 veins traverse the sandstone of the Vosges, a formation whose geological position is not 
 altogether well known, but which contains iron mines analogous to the preceding at 
 Langenthal, at the foot of Mount Tonnerre, and in the Palatinate. Many analogies 
 seem to approximate to the sandstone of the Vosges, the sandstone of the environs of 
 Saint Avoid (Moselle), which include the mine of brown hematite of Creutzwald, and 
 the lead mine of Bleyberg, analogous to the lead mine of Bleyberg, near Aix-la- 
 Chapelle. 
 
MINES. 
 
 169 
 
 At Cruttnich and Tholey, to the north of the Sarrehruck, mines of manganese are 
 worked, famous for the good quality of their products. The deposit exploited at 
 Cruttnich, seems to be inclosed in the sandstone of the Vosges, and to constitute a vein 
 in it, analogous to the iron veins mentioned ahove. 
 
 There has been recently opened a manganese mine at Lavettine near La Crcix-aux- 
 mines, in a district of gneiss with porphyry. 
 
 In the Vosges and the Black Forest there are several deposits of anthracite (stone- 
 coal), of which two are actually worked, the one at Zunsvvir near Offenbourg, in the 
 territory of Baden, and the other at Uvoltz, near Cernay, in the department of the 
 Upper Rhine. There are also several deposits of the true coal formation on the flanks 
 of the Vosges. 
 
 MINES OF THE HARTZ. 
 
 The name Hartz is given generally to the country of Forests, which extends a great 
 many miles round the Brocken, a mountain situated about 55 miles W. S. W. of Magde- 
 burg, and which rises above all the mountains of North Germany, being at its summit 
 1226 yards above the level of the sea. The Hartz is about 43 miles in length from 
 S. S.E. to N. N.W., 18 miles in breadth, and contains about 450 square miles of surface. 
 It is generally hilly, and covered two-thirds over with forests of oaks, beeches, and firs. 
 This rugged and picturesque district corresponds to a portion of the Silva Hercynia of 
 Tacitus. As agriculture furnishes few resources there, the exploration of mines is 
 almost the only means of subsistance to its inhabitants, who amount to about 50,000. 
 The principal cities, Andreasberg, Clausthal, Zellerfeld, Altenav, Lautenthal, Wildemunn, 
 Grund, and Goslar, bear the title of mine-cities, and enjoy peculiar privileges ; the people 
 deriving their subsistence from working in the mines of lead, silver, and copper, over 
 which their houses are built. 
 
 The most common rock in the Hartz is greywacke. It encloses the principal veins, 
 and is covered by a transition limestone. The granite of which the Brocken is formed 
 supports all this system of rocks, forming as it were, their nucleus. Trap and hornstone 
 rocks appear in certain points. 
 
 The veins of lead, silver, and copper, which constitute the principal wealth of the 
 Hartz, do not pervade its whole extent. They occur chiefly near the towns of Andreas- 
 berg, Clausthal, Zellerfeld, and Lautenthal; are generally directed fromN.W. to S. E., 
 and dip to the S. W., at an angle of 80° with the horizon. 
 
 The richest silver mines are those of the environs of Andreasberg, among which may 
 be distinguished the Samson and Neufang mines, worked to a depth of 560 yards. In 
 the first of them, there is the greatest step exploitation to be met with in any mine. It 
 is composed of 80 direct steps, and is more than 650 yards long. These mines were 
 discovered in 1520, and the city was built in 1521. They produce argentiferous 
 galena, with silver ores properly so called, such as red silver ore, and ore of cobalt. 
 
 The district which yields most argentiferous lead, is that of Clausthal. It compre- 
 hends a great many mines, several of which are worked to a depth of 550 yards. Such 
 of the mines as are at the present day most productive, have been explored since the 
 first years of the 1 8th century. The two most remarkable ones are the mines of 
 Dorothy, and the mine of Caroline, which alone furnish a large proportion of the whole 
 neat product. The grant of the Dorothy mine extends over a length of 257 yards, in 
 the direction of the vein, and through a breadth of nearly 22 yards perpendicularly to 
 that direction. Out of these bounds, apparently so small, but which however surpass 
 those of the greater part of the concessions in the Hartz, there was extracted from 1709 
 to 1807 inclusively, 883,722 marcs of silver, 768,845 quintals of lead, and 2385 quintals 
 of copper. This mine and that of Caroline have brought to their shareholders in the 
 same period of time, more than 1,120,000/. ; and have besides powerfully contributed 
 by loans without interest to carry on the exploration of the less productive mines. It 
 was in order to effect the drainage of the mines of the district of Clausthal, and those 
 of the district of Zellerfeld adjoining, that the great gallery of efflux was excavated. 
 
 Next to the two districts of Clausthal and Zellerfeld, and Andreasberg, comes that of 
 Goslar, the most important working in which is the copper mine of Rammelsberg, 
 opened since the year 968, on a mass of copper pyrites, disseminated through quartz, 
 and mingled with galena and blende. It is worked by shafts and galleries, with the em- 
 ployment of fire to break down the ore. This mine produces annually from 1200 to 1300 
 metric quintals (about 275,000 libs, avoird.) of copper. The galena extracted from it 
 yields a small quantity of silver, and a very little gold. The latter metal amounts 
 to only the five millionth part of the mass explored ; and yet means are found to 
 separate it with advantage. The mine of Lanterberg is worked solely for the copper, 
 and it furnishes annually near 66,000 libs, avoird. of that metal. 
 
 Besides the explorations just noticed, there are a great many mines of iron in different 
 parts of the Hartz, which give activity to important forges, including 21 smelting 
 
 Z 
 
170 
 
 MINES. 
 
 cupolas. The principal ores are sparry iron, and red and brown hematites, which occur 
 in veins, beds, and masses. Earthy and alluvial ores are also collected. 
 
 The territory of Anhalt-Bernbourg presents, towards the S. E. extremity of the 
 Hartz, lead and silver mines, which resemble closely those of the general district. They 
 produce annually 33,000 libs, avoird. of lead. 
 
 At the southern foot of the Hartz, at Ilefeld, there is a mine of manganese. 
 
 The exploration of the Hartz mines may be traced back for about 900 years. The 
 epoch of their greatest prosperity was the middle of the 18th century. Their gross 
 annual amount was in 1 808, upwards of one million sterling. Lead is their principal 
 product, of which they furnish annually 6,600,000 libs, avoird., with 36,000 marcs, or 
 18,700 libs, avoird. of silver, about 360,000 libs, avoird. of copper, and a very great 
 quantity of iron. They are celebrated for the excellence of the mining operations ; and 
 the activity, patience, and skill of their workmen. 
 
 The Hartz is referred to especially for the manner in which the waters are collected, 
 and economised for floating down the timber, and impelling the machinery. With this 
 view, dams or lakes, canals and aqueducts, have been constructed, remarkable for their 
 good execution. The water-courses are formed either in the open air round the 
 mountain sides, or through their interior as subterranean galleries. The open channels 
 collect the rain waters, as well as those proceeding from the melting of snows, from the 
 springs and streamlets, or small rivers that fall in their way. The subterranean con- 
 duits are in general the continuation of the preceding, whose circuits they cut short. 
 These water-courses present a development in whole, of 125 miles. The banks of some 
 of the reservoirs are of an extraordinary height. In the single district of Clausthal 
 there are 34 tanks, which supply water to 92 wheels of nearly 30 feet diameter. 55 of 
 these serve for the drainage of water; and 37 for the extraction of ores. 
 
 MINES OF THE EAST OF GERMANY. 
 
 We shall embrace under this head the mines opened in the primitive and transition 
 territories, which constitute the body of a great portion of Bohemia, and the adjacent 
 parts of Saxony, Bavaria, Austria, Moravia, and Silesia. 
 
 Among the several chains of small mountains that cross these countries, the richest 
 in deposits of ore is the one known tinder the name of the Erzgebirge, which separates 
 Saxony from Bohemia on the left bank of the Elbe. 
 
 The Erzgebirge contains a great many mines whose principal products are silver, tin, 
 and cobalt. These mines, whose exploration remounts to the 12th century, and par- 
 ticularly those situated on the northern slope within the kingdom of Saxony, have been 
 long celebrated. The school of mines established at Freyberg, was at one time 
 considered as the first in the world. This is a small city near the most important 
 workings, 8 leagues W. S. W. of Dresden, towards the middle of the northern slope 
 of the Erzgebirge, 440 yards above the level of the sea, in an agricultural and trading 
 district, well cleared of wood. These circumstances have modified the working of the 
 mines ; and render it difficult to draw an exact parallel between them, and those of the 
 Hartz, which are their rivals in good exploration. They are peculiarly remarkable 
 for the perfection with which the engines are executed both for drainage and extraction 
 of ores, all moved by water or horses ; for the regularity of almost all the subterranean 
 labours ; and for the beauty of their walling masonry. In the portion of these moun- 
 tains belonging to Saxony, the underground workings employ directly from 9000 to 
 10,000 men, who labour in more than 400 distinct mines, all associated under the same 
 plan of administration. 
 
 The silver mines of the Erzgebirge are opened on veins which traverse gneiss, and 
 though quite different in this respect from the argentiferous veins of Guanaxuato, 
 Schemnitz, and Zmeof, present but a moderate thickness, never exceeding a few feet. 
 They form several groups, whose relative importance has varied very much. 
 
 For a long time back, those cf the environs of Freyberg are much the most produc- 
 tive ; and their prosperity has been always on the advance, notwithstanding the increas- 
 ing depth of the excavations. The deepest of the whole is that of Kuhschacht, which 
 penetrates to 450 yards beneath the surface, that is nearly down to the sea-level. The 
 most productive and the most celebrated is the mine of Himmelsfiirst ; that of Beschert- 
 gluck is also very rich. 
 
 Among the explorations of the Erzgebirge, there are none which were formerly so 
 flourishing as those of Marienberg, a small town situated seven leagues S. S. W. of 
 Freyberg. In the 16th century, ores were frequently found there, even at a short dis- 
 tance from the surface, which yielded 85 per cent, of silver. The disasters of the thirty 
 years' war put a term to their prosperity. Since that period they have continually 
 languished ; and their product now is nearly null. 
 
 Our limits do not permit us to describe in detail the silver mines that occur near 
 
MINES. 
 
 171 
 
 Ehrenfriedersdorf, Johanna - Georgenstadt, Annaberg, Oberwiescnthal, and Schneeberg. 
 Those of the last three localities produce also cobalt. 
 
 The mines of Saint- Georges, near Schneeberg, opened in the 15th century as iron 
 mines, became celebrated some time after as mines of silver. Towards the end of the 
 15th century, a mass of ore was found there which afforded 400 quintals of silver. On 
 that lump, Uuke Albert kept table at the bottom of the mine. Their richness in silver 
 has diminished since then ; but they have increased more in importance during the last 
 two hundred years, as mines of cobalt, than they had ever been as silver mines. Saxony 
 is the country where cobalt is mined and extracted in the most extensive manner. It 
 is obtained from the same veins with the silver. Smalt, or cobalt-blue, is the principal 
 substance manufactured from it. The lead and the copper are in this country only 
 accessory products of the silver mines, from which 1 20,000 lbs. avoird. of the first of 
 these metals are extracted, which are hardly sufficient for the metallurgic operations ; 
 and from 50,000 to 60,000 lbs. of copper. A little bismuth is extracted from the mines 
 of Schneeberg and Freyberg. Some manganese is found in the silver mines of the 
 Erzgebirge, and particularly at Johann- Georgenstadt. 
 
 The mines of Saxony produce a little argentiferous galena, and argentiferous gray 
 copper ; the minerals with a base of native silver are the principal ores. They are treated 
 in a great measure by amalgamation. All those of Freyberg are carried to the excel- 
 lent smelting house of Halsbriick, situated on the Malde, near that city. The average 
 richness of the silver ores throughout Saxony is only from 3 to 4 oz. per quintal ; viz. 
 nearly equal to that of the ores of Mexico, and very superior to the actual richness of 
 the ores of Potosi. The silver extracted from them contains a little gold. The Saxon 
 mines produce annually 52,000 marcs of silver. Of these, the district of Freyberg alone 
 furnishes 46,000 ; and among the numerous mines of that district, that of Himmelsfurst 
 of itself produces 10,000 marcs. 
 
 Silver mines exist also on the southern declivity of the Erzgebirge, which belongs to 
 Bohemia, at Joachimsthal and Bleystadt, to the N. E. of Eger. Argentiferous galena is 
 chiefly extracted from these. The mines of Joachimsthal have been explored to a 
 depth of 650 yards. They were formerly very flourishing; but in 1805 they were 
 threatened with an impending abandonment. The ancient mines of Kuttenbcrg, 
 situated in the same region, have been excavated, according to Agricola, to upwards of 
 1000 yards from the surface soil. 
 
 The southern slope of the Erzgebirge possesses cobalt mines like the northern slope ; 
 but they are of much less importance. Some occur, particularly in the neighbourhood 
 of Joachimsthal. Lastly, on the same slope, slightly productive copper mines are 
 mentioned at Grb'slitz, near Joachimsthal ; at Catharineberg, eight leagues N. of Saatz ; 
 and at Kupferberg, lying between the two. At Grb'slitz, the ore is a cupreous pyrites, 
 accompanied by blende. The ores of Catharineberg are argentiferous. 
 
 Next to the silver mines, the most important explorations of the Erzgebirge are those 
 of tin. This metal occurs in veins, massive, and disseminated in masses of hyalin 
 gray quartz, imbedded in the granite. It is also found in alluvial sands. The most 
 important tin mine of the Erzgebirge is that of Altenberg, in Saxony, which has been 
 under working since the 15th century. Some tin is mined also near Gayer, Ehren- 
 friedersdorf, Johann- Georgenstadt, Scheibenberg, Annaberg, Seiffen, and Marienberg, 
 in Saxony. At Zinnwald it is also found; where the stanniferous district belongs 
 partly to Saxony, and partly to Bohemia ; as also important mines occur in the latter 
 territory at Sehlackenwald and Abertham, and slightly productive ones at Flatten and 
 Joachimsthal. In several cf these mines, particularly at Altenberg and Gayer, fire is 
 employed for attacking the ore, because it is extremely hard. In almost the whole of 
 them, chambers of too great dimensions have been excavated, whence have arisen, at 
 different epochs, vexatious sinkings of the ground. One of these may still be seen at 
 Altenberg, which is 130 yards deep, and nearly 50 in breadth. The mines of Aber- 
 tham are explored to a depth of 550 yards ; and those of Altenberg to 330. The tin 
 mines of the Erzgebirge produce annually 484,000 lbs. avoird. of this metal. 
 
 The tin ores are accompanied by arsenical pyrites, which, in the roasting that it 
 undergoes, produces a certain quantity of arsenious acid. 
 
 The Erzgebirge presents also a great many iron mines, particularly in Saxony, at 
 Rodenberg, near Cradorf, in the county of Henneberg, where the workings penetrate to 
 a depih of 220 yards, and in Bohemia, at Plat/en, where may be remarked especially 
 the great explorations opened on the vein of the Irrgang. 
 
 There is also in the Erzgebirge a mine of anthracite (stone coal) at Schanfeld, near 
 Frauenstein in Saxony. 
 
 The ancient rock formations which appear in the remainder of Bohemia, and in 
 the adjacent portions of Bavaria, Austria, Moravia, and Silesia, are much less rich in 
 metals than the Erzgebirge. No explorations of much importance exist there. 
 
 The Fichtelgebirge, a group of mountains standing at the western extremity of the 
 
 Z 2 
 
172 
 
 MINES. 
 
 Erzgebirge, between Hoff and Bayreuth, contains some mines, among which may be 
 noticed, principally, mines of magnetic black oxide of iron. 
 
 Argentiferous lead mines have been mentioned at Miess, 25 leagues W. S. W. of 
 Prague, at the N. E. base of the western part of Bomerwaldgebirge, a chain of mountains 
 which separates Bohemia from Bavaria. There are some also at Prszibram, 12 leagues 
 S. W. of Prague, at the extremity of the mountains which separate Behrun from 
 Moldau. In the latter, the argentiferous galena is accompanied by blende, in which 
 the presence of cadmium has been observed. These mines, and those of Joacliimsthal 
 and of Bleystadt, furnish annually at present 220,000 pounds avoird. of lead, and from 
 2000 to 3000 marks of silver. The circle of Behrun, to the S.W. of Prague, contains 
 some inconsiderable mines of mercury. The eastern part of the Bomerwaldgebirge, 
 which separates Bohemia from Austria and Moravia, presents some mines on its S.E. 
 slope. Those of the environs of Iglau, in Moravia, and some others situated in 
 Austria, produce annually from 4000 to 5000 marks of silver. The mines of these two 
 countries yield also copper, and in several the copper , ores are argentiferous. Moravia 
 comprehends several iron works, which are in part supplied by magnetic iron ores 
 analogous to those of Sweden. 
 
 The N. E. slope of the Riesengebirge (giant mountains), which separate Bohemia 
 from Silesia, presents also several explorations. The argentiferous copper mines of 
 Rudolstadt and of Kupferberg, have been stated as producing annually a considerable 
 quantity of copper, and from 600 to 700 marcs of silver ; as also the cobalt mine of 
 Maria-anna Querback, the whole in the circle of Qauer ; and the mines of arsenical 
 pyrites at Reichenstein, in the circle of Glatz. A mine of chrysoprase exists in the 
 mountain of Kosennitz. 
 
 MINES OF THE CENTRE OF FRANCE. 
 
 The antient formations, principally granitic, which constitute the ground of several 
 departments of the centre and south of France, are hardly any richer in explor- 
 ations than the districts mentioned at the end of the Black Forest. Only some in- 
 sulated mines are to be observed here, of which a very few possess any importance. 
 These all occur towards the eastern border of the mass of primitive formations, in a 
 zone characterised by a great abundance of schistose rocks. 
 
 At Villefort and at Viallaze, in the department of the Lozere, and in some places 
 adjoining, several veins of argentiferous galena are worked which traverse the gneiss 
 and the granite. These mines, remarkable at present for the regularity of their work- 
 ings, employ 300 labourers, and produce annually about 220,000 lbs. avoird. of lead, 
 and 1600 marks of silver. 
 
 The city of Vienne, in Dauphiny, is built on a hill of gneiss separated by the Rhone 
 from the main body of the primitive formations, and in which veins of galena occur, 
 which are now imperfectly mined. Other lead mines of less importance are observed 
 at St. Julien- Molin- Molette, department of the Loire, and at Joux, department of the 
 Rhone. 
 
 At Chessy, a village situated 7 leagues N. W. of Lyons, there occur in a talcose 
 schist very extensive veins of cupreous pyrites, by no means rich, but which have, never- 
 theless, been worked successfully during the latter part of the 1 8th century, and several 
 years of the present. At that period, there was found in a sandstone which covers the 
 talcose schist, and which appears referrible to the red sandstone or the variegated 
 sandstone, a bed containing a great quantity of blue carbonate of copper and prot- 
 oxide of copper, to the working of which the miners have since directed their prin- 
 cipal attention. There exists at Saint- Belle, 2 leagues to the south of Chessy, a deposit 
 of copper pyrites like that of Chessy, which was at one time worked, but is now 
 standing still. At Romanescho, in the department of Saone et Loire, a very abundant 
 deposit of oxide of manganese is observed, apparently forming a mass in the granite, 
 or perhaps above it. The workings are very irregular. 
 
 In the mountain of Ecouchettes near Couches, in the same department, an ore of 
 oxide of chrome has been occasionally worked. 
 
 At Malbosc, in the department of the Lozere, a feeble vein of sulphuret of antimony 
 is mined. 
 
 There are also in the centre of France some explorations of galena, antimony, and 
 manganese, which appear to be of too little importance to be noticed in detail. 
 
 Some years ago a tin ore was discovered at Vaubry, six leagues N. N. W. of Li- 
 moges. At present researches are making with a view of discovering deposits <of such 
 magnitude as to pay the expense of working it. 
 
 MINES OF THE NORTH OF PORTUGAL AND THE ADJOINING PARTS OF SPAIN. 
 
 The Carthaginians appear to have worked tin mines in this part of the Peninsula. It is 
 said that some formerly existed in Portugal, in the environs of Viseu, a province of Beira, at 
 
MINES. 
 
 173 
 
 a place called Burraco de Stanno. Some veins of the same metal were discovered in 1 787, 
 near Monte- Rey, in the south of Gallicia. They were fully two yards thick, and were 
 incased in granite. This province presents also deposits of sulphuret of antimony. 
 Some analogous ores are found in Castille and Estremadura. Lead ores were worked in 
 the last century not far from Mogadouro, on the banks of the Sabor, in the province of 
 Tras-los-Montes, and near Longroiva on the banks of the Rio-Prisco. Mines of plum- 
 bago occur near Mogadouro. There are also some iron mines in the same country near 
 Felguiera and Torredemnacorvo. They supply the iron-works of Chapa-cunha. Two 
 very ancient establishments of the same kind exist in the Estremadura of Portugal ; 
 the one in the district of Thomar, and the other in that of Figuiero dos Vinhoss : they 
 are supplied by mines of red oxide of iron, situated on the frontiers of this province and 
 of Beira. One deposit of quicksilver ore occurs at Couna in Portugal. At Rio Tinto 
 in Spain, on the frontiers of Portugal, there is a copper mine which produces about 
 33,000 libs, avoird. of this metal per annum. The ore is a copper pyrites. The moun- 
 tains in the environs of Oporto present everywhere indications of the ores of copper and 
 other metals ; and it appears that all this part of the Peninsula is in general rich in me- 
 tallic treasures, but that the want of wood prevents their being mined to advantage. 
 
 Besides, many of the deposits which originally existed there must be in a great mea- 
 sure exhausted. It was in these countries chiefly that the gold and silver mines lay, which 
 the Carthaginians and Romans worked with so much advantage, and contested in so keen 
 a manner. Near Loria (the ancient Numantium), Azagala, and Burgos, considerable 
 vestiges of the ancient workings may still be seen. 
 
 MINES OF BRITANNY. 
 
 Britanny has hardly a better share in mineral wealth than the countries we have just 
 passed in review. There exist in it at this moment only two important exploitations ; 
 which are, the lead mines of Poullaouen and Huelgoat, situated near Carhaix. The mine 
 of Huelgoat, celebrated for the plomb-gomme (hydro-aluminate) discovered in it, is 
 opened on a vein of galena, which traverses transition rocks. The workings have sub- 
 sisted for about three centuries, and have attained to a depth of 220 yards. The vein of 
 Poullaouen, called the New Mine, was discovered in 1741. It was powerful and very 
 rich near the surface ; but it became subdivided and impoverished with its depth, notwith- 
 standing which the workings have been sunk to upwards of 1 80 yards below the sur- 
 face. In these mines there are fine hydraulic machines for the drainage of the waters, with 
 wheels from 14 to 15 yards in diameter ; and water-pressure machines have been recently 
 constructed. The mines employ more than 900 workmen, and furnish annually more than 
 1,200,000 lbs. avoird. of lead, several thousand pounds of copper, and 2000 marks, or 
 1034 lbs. avoird. of silver. These are the most important metallic mines of France. 
 Several veins of galena exist at Chateldudren, near Saint- Briex, but they are not worked 
 at present. There is also one at Pompean, near Rennes, which has been worked to a 
 depth of 140 yards, but is in like manner now abandoned. It affords, besides the 
 galena, a very large quantity of blende (sulphuret of zinc), of which attempts are 
 making to take advantage. There occurs, also, a lead mine at Pierreville, department 
 of the Channel, in a formation connected with the system of Brittany. It is opened on 
 a vein which traverses a limestone pretty analogous to that of Derbyshire. The same 
 department presents a deposit of sulphuret of mercury at Menildot. A few years ago, 
 some tin ore was discovered at Pyriac, near Guerande, in the department of the Loire In- 
 ferieur, but the researches since made to find workable deposits have been unsuccessful. 
 A mine of antimony was worked at La Ramee, department of La Vendee. Several of the 
 coal deposits lately mined in the departments of La Sarthe, La Mayenne, and Mayenne-et- 
 Loire, ought probably to be regarded as more ancient than the genuine coal measures. 
 
 Table of the Production of the French Mines, during the year 1832.* 
 
 Species of Mine. 
 
 Number of 
 Mines. 
 
 Extent of 
 Surface 
 conceded, 
 
 Number of 
 Workmen. 
 
 Production is in 
 lOths of a ton. 
 
 Value of the 
 rough product 
 in francs. 
 
 Metallic Substances. 
 
 
 Kilom. carre's. 
 
 
 Melted antim. 
 
 
 Antimony 
 
 16 
 
 93,8954 
 
 130 
 
 71-232,75 
 
 
 
 
 1 -030 98 
 
 
 Copper 
 
 8 
 
 274,18 
 
 258 
 
 Black copper 
 
 247-680 
 
 
 
 
 
 I -376 
 
 
 Iron 
 
 131 
 
 1-051,391 
 
 8917 
 
 Rough ore 
 
 3,630-806,81 
 
 
 
 
 
 15-814,690 
 
 
 Manganese 
 
 8 
 
 16,54 
 
 66 
 
 6-087 
 
 66-849,88 
 
 Gold 
 
 
 0-49 
 
 
 
 
 Lead and Silver - 
 
 33 
 
 614,23 
 
 1259 
 
 8-505 
 
 742-051 
 
 Zinc 
 
 1 
 
 6,80 
 
 
 
 
 * {Annates dcs Mines, torn, v., 1834, p. 676.) 
 
174 
 
 MINES. 
 
 MINES OF THE CORRESPONDING COASTS OF GREAT BRITAIN AND IRELAND. 
 
 The mines comprehended in this section are situated, 1. in Cornwall and Devonshire ; 
 2. in the S. E. of Ireland ; 3. in the island of Anglesey and the adjoining part of Wales ; 
 4. in Cumberland, Westmoreland, the north of Lancash ire, and the Isle of Man ; 3. in 
 the south of Scotland ; 6. in the middle part of the same country. 
 
 Cornwall and Devonshire present three principal mining districts ; viz. the portion of 
 Cornwall situated in the environs and S.W. of Truro, the environs of St. Austle, and the 
 environs of Tavistock. 
 
 The first of these districts is the most important of the three in the number and richness 
 of its mines of copper, tin, and lead. The ores of copper, which consist almost entirely 
 of copper pyrites and common sulphuret of copper, constitute very regular veins running 
 nearly from east to west, and incased most frequently in a clay-slate of a talcose or horn- 
 blende nature, called killas, and sometimes in granite, which forms protuberances in the 
 middle of the schists. The tin occurs principally in veins, which, like the preceding, 
 traverse the killas and the granite. They are also very often directed nearly from east to 
 west, but they have a different inclination, or dip, from that of the copper veins, which 
 cut them across and interrupt them, and are consequently of more reetent formation. The 
 tin ore forms also masses, which appear most usually attached to the veins by one of 
 their points. Lastly, it is found in small veins which traverse the granite, principally 
 near the points where this rock touches the killas. Certain veins present the copper and 
 tin ores together ; a mixture which occurs chieliy near the points of intersection of the 
 two metallic veins. Certain mines furnish at once both copper and tin ; but the most part 
 produce in notable quantity only one of these metals. The most important copper 
 mines are situated near Redruth and Camborn ; amongst which may be noted particu- 
 larly those called Consolidated Mines, United Mines, Huel- Alfred, Dolcoath, Poldice, 
 &c. The principal tin mines are situated still farther to the south-west, near Helston, 
 Saint- Yues, &c. Those called Huel Vor, Great Huas, are particularly noticed. There 
 are several mines in Cornwall, of which the crossing veins which at once intersect and 
 throw out the veins of copper and tin, contain argentiferous galena and several ores of 
 silver. There existed formerly mines of argentiferous lead near Helston and Truro. 
 There may be now seen near Saint Michael an ore which, melted and cupelled on the 
 spot, yields from an ounce and a half to two ounces of silver per quintal. Near Cal- 
 stock a silver mine is worked, called Huel- Saint- Vincent, which has afforded, it is said, 
 in some months, from 900 to 1000 lbs. avoird. of that metal. The ore, consisting of 
 hornsilver and native silver, is treated on the spot. 
 
 In the environs of Saint Austle, the copper mines of Extst Orinnis and West Crinnis 
 deserve to be noticed, as well as the tin mine of Polgooth, opened on a tin vein; and the 
 mine of Carclaise, explored in the open air on a system of small veins of this metal. 
 
 Near Tavistock there occur mines of copper, tin, and lead. Among the last may be 
 remarked particularly that called Huel Betsey, of which the ores melted and cupelled on 
 the spot, afford an ounce and a half of silver per cwt. ; and that of Beeralston, whose 
 ore is sent to Bristol to be smelted there. It yields from four to five ounces of silver 
 per cwt. 
 
 There are mines of antimony at Huel-Boys in Devonshire, and at Saltash in Corn- 
 wall. 
 
 The tin and copper ores of Cornwall are accompanied with arsenical pyrites, which is 
 turned to some account by the fabrication of white arsenic (arsenious acid). 
 
 Cornwall and Devonshire produce annually about 6,160,000 lbs. avoird. of tin; 
 1 8,700,000 lbs. avoird. of copper : and 1,760,000 lbs. avoird. of lead. See Copper and Tin. 
 
 The tin is treated at the mine localities ; but the copper ores are sent in their natural 
 state to Swansea in South Wales, to be smelted. 
 
 Wood and labour being very dear in Cornwall and Devonshire, the mineral deposits 
 of these counties cannot be worked out so completely, nor can the mechanical prepara- 
 tion of the ores be so far pushed, as in several other parts of the world. But all the ope- 
 rations which appear advantageous are conducted in the most judicious, most economical, 
 and most expeditious manner. Steam engines are erected there, some of them possess- 
 ing the power of several hundred horses. Many of the mines are explored to a depth of 
 upwards of 400 yards ; and several are celebrated for the boldness of their workings. 
 The one called Botallock Mine, situated in the parish of St. Just, near the Cornwall 
 cape, is opened amid rocks which form the sea-coast, and stretches several hundred 
 yards under the sea, and upwards of 200 yards beneath its level. In some points so 
 small a thickness of rock has been left to support the weight of the waters, that the roll- 
 ing of pebbles on the bottom is distinctly heard by miners during a storm. The mine 
 of Huel-werry, near Penzance, was worked by means of a single shaft opened on the 
 coast, in a space left dry by the sea only for a few hours at every ebb. A small wooden 
 tower was built over the mouth of the shaft, which, being carefully caulked, kept cut 
 
MINES. 
 
 175 
 
 the waters of the ocean when the tide rose, and served to support the machines t'or 
 raising the ore and drainage. A vessel driven by a storm overturned it during the night, 
 and put a period to this hazardous mode of mining, which has not been resumed. 
 
 The most considerable mines of Ireland are those of Cronebane and Tingrony, and of 
 Ballymartagh, situated three leagues S. W. of Wicklow, in the county of the same name. 
 Their object is to work the copper pyrites, accompanied with some other ores of copper, 
 galena, sulphuret of antimony, as well as pyrites of iron, which forms several flattened 
 masses in the clay-slate. Pretty extensive workings have been made here ; and the ore 
 was transported in its natural state to Swansea. Veins or masses of copper pyrites and 
 galena are mined in some other points of the south-east of Ireland, but none of them with 
 any notable advantage. The principal is the lead mine situated in the county of Tipperary, 
 near the village called Silver Mines, absurdly enough, because, though silver was sought 
 for in the lead, none was extracted. Many iron mines anciently existed in Ireland, but 
 the destruction of the forests has considerably diminished their number and activity, so 
 that only a few remain in Kilkenny, Wicklow, and Queen's County. 
 
 The isle of Anglesey is celebrated for its copper mines, the principal of which are 
 Mona-mine and Parys-mountain, The ore is a copper pyrites, sometimes of considerable 
 volume, lying in masses in a formation containing serpentines and different talcose rocks. 
 For a long time the workings were carried on in the open air, but the exterior explor- 
 ation has been thereby compromised. The neighbouring coasts of Wales present some 
 mines of the same nature. All the ores are treated in a smelting-house established in 
 the isle of Anglesey. The formation of slate-clay and greywacke, which constitutes the 
 greater part of Wales, and some of the adjoining districts of England, includes several 
 lead mines, of which we shall presently speak in noticing those of far greater importance 
 contained in the more recent limestone formations of the same regions. 
 
 Pretty important mines of copper pyrites and red hematitic iron are worked in 
 Westmoreland, and in the neighbouring parts of Cumberland and Lancashire. The 
 copper ores, and a portion of the iron ones, are embarked for Swansea. The rest of the 
 iron ore is treated on the spot in blast furnaces supplied with wood charcoal. The 
 isle of Man affords indications of lead, copper, and iron in the mountains of Snafle, 
 which constitute its centre. At Borrowdale in Westmoreland, a mine of graphite 
 (plumbago) has been worked for a long period. It furnishes the black lead of the 
 English pencils, so celebrated over the world. The mineral occurs in mass in a talcose 
 formation. 
 
 There are famous lead mines in the south of Scotland, at Leadhills in Lanarkshire ; 
 the veins of which are incased in greywacke. Some manganese has also been found. 
 At Cally, in Kirkcudbrightshire, a copper mine has been lately discovered; and a mine 
 of antimony has been known for some time at West Kirk in Dumfriesshire ; but neither 
 has been turned to good account. 
 
 In the middle part of Scotland, the lead mines of Strontian in Argyleshire deserve to 
 be noticed, opposite to the north-east angle of the isle of Mull. They are opened on 
 veins which traverse gneiss. According to Mr. John Taylor, these mines and those 
 of Leadhills produce annually 5,610,000 lbs. avoird. of lead. 
 
 Explorations of manganese were begun at Grantown on the banks of the Don, a river 
 which falls into the German Ocean at Aberdeen. A mine of coarse graphite has also 
 been worked at Huntley. 
 
 A copper mine was discovered some years back in one of the Shetland isles ; and 
 chromate of iron is now extensively worked there in serpentine and talc. 
 
 MINES OF THE NORTH OF EUROPE. 
 
 These mines are situated for the most part in the south of Norway, towards the 
 middle of Sweden, and in the south of Finland, a little way from the shortest line drawn 
 from the lake Onega to the south-west angle of Norway. A few mines occur in the 
 northern districts of Norway and Sweden. The main products of these several mines 
 are iron, copper, and silver. 
 
 The iron mines of Norway lie on the coasts of the Gulph of Christiania, and on the side 
 facing Jutland, principally at Arendal, at Krageroe, and the neighbourhood. The ores 
 consist almost solely of black oxide of iron, which forms beds or veins of from 4 to 60 feet 
 thick, incased in gneiss, which is accompanied with pyroxene (augite), epidotes, garnets, 
 &c. These iron ores are reduced in a great, many smelting forges, situated on the same 
 coast, and particularly in the county of Laurwig. Their annual product is about J 6£ 
 millions of pounds avoird. of iron, in the form of cast iron, bar iron, sheet iron, nails, 
 &c. ; of which one half is exported. 
 
 Norway possesses rich copper mines, some of which lie towards the south and the 
 centre of the country, but the most considerable occur in the north, at Quikkne, Leeken, 
 Selboe, and Rozraas, near Drontheim. The mine of Rceraas, 16 miles from Drontheim to 
 
176 
 
 MINES. 
 
 the S. E. of this city, is opened on a very considerable mass of copper pyrites, and has 
 been worked in the open air since 1664. It has poured into the market from that 
 time, till 1791, 77 millions of pounds avoird. of copper. In 1805, its annual production 
 was 864.600 libs. ; while all the other mines of Norway together do not furnish quite 
 one-fourth of that amount. 
 
 Norway comprehends also some celebrated silver mines. They are situated from 15 
 to 20 leagues S. W. of Christiania, in a mountainous country near the city of Kongsberg, 
 which owes to them its population. Their discovery goes back to the year 1623, and 
 their objects are veins of carbonate of lime, accompanied with asbestos and other sub- 
 stances in which native silver occurs, usually in small threads or networks, and some- 
 times in considerable masses, along with sulphuret of silver. These veins are very nu- 
 merous, and run through a considerable space, divided into four districts (arrondisse- 
 mens), each of which contains more than 15 distinct explorations. When a new mine is 
 opened, an excavation in the open air is first made, which embraces several veins, and 
 they then prosecute by subterranean workings only those that appear to be of consequence. 
 The workings do not exceed 1000 feet in depth. Fire is employed for attacking the 
 ore. In 1782, the formation of a new gallery of efflux was commenced, destined to have 
 a length of 10,000 yards, and to cost 60,000Z. These mines, since their discovery till 1792, 
 have afforded a quantity of silver equivalent to four millions of pounds sterling. The 
 year 1768 was the most productive, having yielded 38,000 marcs of silver. At present 
 they give but a very slender return ; in 1804 they were threatened with a complete aban- 
 donment. The ore is treated by fusion ; the lead necessary for this operation being 
 imported from England. There are, however, lead and silver mines in the county of 
 Jarlsberg, but they are very slenderly worked. 
 
 At Edswald, 50 leagues N. of Christiania, a mine is worked of auriferous pyrites, with 
 a very inconsiderable product. 
 
 Cobalt mines may be noticed at Modum or Fossum, 8 leagues W. of Christiania ; 
 they are extensive, but of little depth. 
 
 Lastly, graphite is explored at Englidal ; and chromite of iron deposits have been 
 noticed in some points of Norway. 
 
 The irons of Sweden enjoy a merited reputation, and form one of the chief objects of 
 the commerce of that kingdom. Few countries, indeed, combine so many valuable ad- 
 vantages for this species of manufacture. Inexhaustible deposits of iron ore are placed 
 amid immense forests of birches and resinous trees, whose charcoal is probably the best 
 for the reduction of iron. The different groups of iron mines and forges form small 
 districts of wealth and animation in the midst of these desolate regions. 
 
 The province of Wermeland, including the north bank of the lake Wener, is one of 
 the richest of Sweden in iron mines. The two most important are those of Nordmarck, 
 3 leagues N. of Philipstadt, and those of Persberg, 2i leagues E. from the same city. 
 Philipstadt is about 50 leagues W. \ N. W. from Stockholm. Both mines are opened 
 on veins or beds of black oxide of iron several yards thick, directed from N. to S. in a 
 ground composed of hornblende, talcose and granitic rocks. These masses are nearly 
 vertical, and are explored in the open air to a depth of 130 yards. Formerly this 
 exploitation was effected by iron wedges and pickaxes ; but they have been superseded 
 by gunpowder, since 1650. The province of Wermeland, and that of Dahl which ad- 
 joins it, forming the west border of the Wener lake, contained in 1767, 48 smelting 
 cones, each going from 4 to 5 months every year. 
 
 The principal iron mines of Rosslagie (part of the province of Upland) are those of 
 Dannemora, situated 1 1 leagues from Upsal. They stand in the first rank of those of 
 Sweden, and even of Europe. The masses worked upon are flattened and vertical, 
 running from N. E. to S. W., and are incased in a ground formed of primitive rocks, 
 among which gneiss, petrosilex and granite are most conspicuous. They amount to three 
 in number, very distinct, and parallel to each other ; and are explored through a length 
 of more than 1500 yards, and to a depth of above 80, by the employment of fire, and blast- 
 ing with gunpowder. The explorations are mere quarries ; each presenting an open 
 trench 65 yards wide, by a much more considerable length, and an appalling depth. 
 Magnetic iron ore is extracted thence, which furnishes the best iron of Sweden and 
 Europe ; an iron admirably qualified for conversion into steel. In 1767, these minings 
 supplied for a long time, 15 smelting cones situated in Rosslagie, at a distance of 10 
 leagues. 
 
 The island of Utoe, situated near the coast of the province of Upland, presents also 
 rich iron mines. The protoxide of iron there forms a thick bed in the gneiss. It is 
 worked in trenches far below the level of the sea. The ore cannot be smelted in the 
 island itself; but is transported in great quantities xo the continent. 
 
 The province of Smoland includes also very remarkable mines. Near Jonkoping, a 
 hill called the Taberg occurs, formed in a great measure of magnetic black oxide of iron, 
 contained in a greenstone reposing on gneiss. 
 
MINES. 
 
 In several parts of Lapland, the protoxide of iron occurs in great beds, or immense 
 masses. At Gellivara, 200 leagues N. of Stockholm, towards the 67th degree of lati- 
 tude, it constitutes a considerable mountain, into which an exploitation has been opened. 
 The iron is despatched on small sledges drawn by rein-deer to streams which fall into 
 the Lutea ; and thence by water carriage to the port of Lutea, where it is embarked for 
 Stockholm. 
 
 There are a great many iron works in Dalecarlia, but a portion of the ores are got 
 from alluvial deposits. Similar deposits exist also In the provinces of Wermeland and 
 Smoland. 
 
 The mines and forges of Sweden produce annually about 165 millions of pounds 
 avoird. (74,000 tons nearly) of cast iron or bar iron; of which two thirds are exported 
 chiefly from the harbours of Stockholm, Gottenburg, Geffle, and Norkoping. 
 
 The copper mines of Sweden are scarcely less celebrated than its iron mines. The 
 principal is that of Fahlun or Kopparberg, situated in Dalecarlia, near the town of 
 Fahlun, 40 leagues N. W. of Stockholm. It is excavated in an irregular and very 
 powerful mass of pyrites, which in a great many points is almost entirely ferruginous, 
 but in others, particularly near the circumference, it includes a greater or less portion of 
 copper. This mass is enveloped in talcose or hornblende rocks. More to the west, 
 there are three other masses almost contiguous to each other, which seem to bend in an 
 arc of a circle around the principal mass. They are explored as well as the last. This 
 was at first worked in the open air ; but imprudent operations having caused the walls 
 to crumble and fall in, since 1647 the excavation presents near the surface nothing but 
 frightful precipices. The workings are now prosecuted by shafts and galleries into the 
 lower part of the deposit, and have arrived at a depth of 194 famnars (nearly 430 yards). 
 They display excavations spacious enough to admit the employment of horses, and 
 the establishment of forges for repairing the miners' tools. It is asserted that the 
 exploration of this mine goes back to a period anterior to the Christian era. During 
 its greatest prosperity, it is said to have produced 1 1 millions of pounds avoird. of cop- 
 per annum, or about 5000 tons. It furnishes now about the seventh part of that 
 quantity ; yielding at the same time about 70,000 lbs. of lead, with 50 marcs of silver, 
 and 3 or 4 of gold. The ores smelted at Fahlun produce from 2 to 2\ of copper per 
 cent. But the extraction of the metal is not the sole process j the sulphur is also pro- 
 cured ; and with it, or the pyrites itself, sulphuric acid and other chemical products are 
 made. Round Fahlun, within the space of a league, 70 furnaces or factories of dif- 
 ferent kinds may be seen. The black copper obtained at Fahlun is converted into rose 
 copper, in the refining hearths of the small town of Ofwostad. 
 
 In the copper mine of Garpenberg, situated 18 leagues from Fahlun, there occur 14 
 masses of ore quite vertical, and parallel to each other, and to the beds of mica-slate or 
 talc-slate, amid which they stand. This mine has been worked for more than six hun- 
 dred years. 
 
 The mine of Nyakopparherg, in Nericia, 20 leagues W. of Stockholm, presents masses 
 of ores parallel to each other, the form and arrangement of which are very singular. It 
 is worked by open quarrying, and with the aid of fire. 
 
 We may notice also the copper mines of Atwidaberg, in Ostrogothia, which furnish 
 annually the sixth part of the whole copper of Sweden. 
 
 There are several other copper mines in Sweden. Their whole number is ten ; but it 
 was formerly more considerable. They yield at the present day in all, about 2,420,000 
 libs, avoird. (1000 tons) of copper. 
 
 The number of the silver mines of Sweden has in like manner diminished. In 1767, 
 only 3 were reckoned under exploration, viz. that of Hellefors in the province of Werme- 
 land ; that of Segcrsfors in Nericia ; and that of Sahla or Sahlberg, in Westmannia, 
 about 23 leagues N. W. of Stockholm. The last is the only one of any importance. 
 It is very ancient, and passes for having been formerly very productive ; though at pre- 
 sent it yields only from 4 to 5000 marcs of silver per annum. Lead very rich in silver 
 is its principal product. It is explored to a depth of more than 200 yards. The 
 soundness of the rock has allowed of vast excavations being made in it, and of even the 
 galleries having great dimensions ; so that in the interior of the workings there are 
 winding machines, and carriages drawn by horses for the transport of the ores. 
 
 At Sahlberg, there are deposits of sulphuret of antimony. 
 
 For the last 30 or 40 years mines of cobalt have been opened in Sweden, principally at 
 Tunaberg and Los, near Nykbping, and at Otward in Ostrogothia. The first are worked 
 upon veins of little power, which become thicker and thinner successively ; whence they 
 have been called bead-veins. It appears that the products of these mines, though of good 
 quality, are inconsiderable in quantity. 
 
 Lastly, there is a gold mine in Sweden ; it is situated at Adelfors, in the parish of 
 Alsfeda, and province of Smoland. It has been under exploration since 1737, on veins 
 of auriferous iron pyrites, which traverse schistose rocks ; presenting but a few inches 
 
 A a 
 
178 
 
 MINES. 
 
 of ore. It formerly yielded from 30 to 40 marcs of gold per annum, but for the last 
 few years it has furnished only from 3 to 4. 
 
 The mines and smelting works of Sweden gave annually, in 1809, a gross product 
 worth 1,463,600/. 
 
 The south of Finland and the bordering parts of Russia contain some mines, but 
 they are far from having any such importance as those of Sweden. 
 
 At Orijerwy near Helsingfbrs, a mine of copper occurs whose gangue is carbonate of 
 lime, employed as a limestone. 
 
 Near Cerdopol, a town situated at the N. W. extremity of the Ladoga lake, veins of 
 copper pyrites were formerly mined. 
 
 Under the reign of Peter the Great, an auriferous vein was discovered in the granitic 
 mountains which border the eastern bank of the lake Ladoga, near Olonetz. It was rich 
 only near the surface ; and its working was soon abandoned. 
 
 Latterly, an attempt has been made to mine copper and iron ores near Eno, above 
 and to the N. \V. of Cerdopol, but with little success. 
 
 Some time ago rich ores of iron, lying in veins, were worked near the lake Shuyna, 
 N. W. from Cerdopol ; but this mine has been also relinquished. 
 
 On the west bank of the Onega lake, there is an iron work at Petrazavodsk, called 
 a zavode, which is the greatest establishment of this kind existing in the north of 
 Russia. 
 
 Nothing is now reduced there except bog iron ore, or swamp ore extracted from small 
 lakes in the neighbourhood. 
 
 The transition limestone which constitutes the body of Esthonia contains lead ore at 
 Arossaar near Fellin. These ores were worked when these provinces belonged to the 
 Swedes. It was attempted in 1806 to resume the exploitation, but without success. 
 
 MINES OF THE ALLEGHANY MOUNTAINS. 
 
 The chain of the Alleghanys, which traverses the United States of America from 
 N. W. to S. E. parallel to the coasts of the Atlantic Ocean, includes a considerable 
 number of deposits of iron, lead, and copper ores ; along with some ores of silver, plum- 
 bago, and chromite of iron. Attempts have been made to mine a great manv of these 
 deposits ; but most of these have been unsuccessful. 
 
 A bed of black oxide of iron occurs in gneiss near Franconia in New Hampshire. 
 It has a power of from 5 to 8 feet ; and has been mined through a length of 200 feet, 
 and to a depth of 90 feet. The same ore is found in veins in Massachusetts and Ver- 
 mont, accompanied by copper and iron pyrites. It is met with in immense quantities 
 on the western bank of the lake Champlain, forming beds of from 1 to 20 feet in thick- 
 ness, almost without mixture, encased in granite. It is also found in the mountains of that 
 territory. These deposits appear to extend without interruption from Canada to the 
 neighbourhood of New York, where an exploration on them may be seen at Crown- 
 Point. The ore there extracted is in much esteem. Several mines of the same species 
 exist in New Jersey. The primitive mountains which rise in the north of this state 
 near the Delaware, include a bed almost vertical of black oxide of iron, which has been 
 worked to 100 feet in depth. In the county of Sussex the same ore occurs, accompanied 
 with Franklinite. At New Milford in Connecticut, a pretty abundant mine of sparry 
 iron occurs ; the only one of the kind known in the Alleghanys. The United States 
 contain a great many iron works, some of which prior to the year 1773, sent over iron 
 to London. They are principally supplied from alluvial iron ore. 
 
 The most remarkable lead mines of the Alleghanys, are those of Southampton in Mas- 
 sachusetts, and of Perkiomen Creek in Pennsylvania, 8 leagues from Philadelphia. The 
 first furnishes a galena, slightly argentiferous ; an ore accompanied with various mine- 
 rals, with base of lead, copper, and zinc, and with gangues (vein-stones) of quartz, 
 sulphate of baryta, and fluor spar. These substances form a vein which traverses 
 several primitive rocks, and is said to be known over a length of more than 6 leagues. 
 At Perkiomen Creek a vein of galena is mined, which traverses a sandstone, referred 
 by many geologists to the old red sandstone. Along with galena a great variety of 
 minerals is found with a basis of lead, zinc, copper, and iron. The mines of lead 
 worked in Virginia, on the banks of the Kanhawa, deserve also to be mentioned. 
 
 None of the copper mines actually in operation in the United States seem to merit 
 particular attention. The mine of Schuyler in New Jersey had excited high hopes, but 
 after the workings had been pushed to a depth of 300 feet, they have been for some 
 years abandoned. The ore, which consisted of sulphuret of copper, with oxide and car- 
 bonate of copper, occurred in a red sandstone. 
 
 In some points of the Alleghanys, deposits have been noticed of chromite of iron and 
 graphite. 
 
 Coal-measures occur in several points of the United States, especially on the N. W. 
 
MINES. 
 
 179 
 
 slope of the Alleghany mountains. The coal is mined successfully on the banks of the 
 Ohio, towards the upper part of its course. See Anthracite. 
 
 MINES OF THE SOUTH OF SPAIN. 
 
 The mountains which separate Andalusia from Estremadura, Leon and La Mancha, 
 and those of the kingdoms of Murcia and Grenada, include some celebrated mines. 
 
 We shall mention first the silver mines of Guadalcanal and Cazalla, situated in the 
 Sierra- Morena, 15 leagues N. of Seville. Among the ores, red silver and argentiferous 
 gray copper have been specified. Their product is inconsiderable ; but this territory 
 presented formerly much more important mines at Villa- Guttiera, not far from Seville. 
 At the beginning of the 17th century they are said to have been worked with such 
 activity, that they furnished daily 170 marcs of silver. More to the east, there exists 
 in the mountains of La Mancha, a mine of antimony, at Santa- Crux-de-Mudela. On 
 the southern slope of the Sierra- Morena, very important lead mines occur, particularly 
 at Linares, 12 leagues N. of Jaen. The veins are very rich near the surface, which 
 causes them not to be mined much in depth ; so that the ground is riddled, as it were, 
 with shafts. More than 5000 old and new pits may be counted ; the greater part of 
 which is ascribed to the Moors. Six of these mines are now explored on account of 
 the crown, and they produce on an annual average, according to M. Laborde, 1,320,000 
 libs, avoird. (about 600 tons) of lead, which is too poor in silver for this precious metal 
 to be extracted with advantage. Bowles states, that there was found at the mines of 
 Linares, a mass of galena, whose dimensions were from 21 to 24 yards in every direc- 
 tion. Abundant mines of zinc occur near Alcaras, 15 leagues N. E. of Linares; which 
 supply materials to a brass manufactory established in that town. There are also lead 
 mines in the kingdoms of Murcia and Grenada. Very productive ores have been 
 worked for some time near Almeria, a harbour situated some leagues to the west of the 
 cape of Gates. The ore is in part treated on the spot with coal brought from New- 
 castle, and in part sent to Newcastle to be reduced there. The kingdoms of Murcia, 
 Grenada, and Cordova, include several iron mines. Near Casalla and Ronda, in the 
 kingdom of Grenada, mines of plumbago are explored. 
 
 On the northern flank of the Sierra- Morena, lie the famous quicksilver mines of 
 Almaden, situated near the town of the same name in La Mancha. They consist of 
 very powerful veins of sulphuret of mercury, which traverse a sandstone, evidently of a 
 geological age as old at least as the coal formation. Hard by, beds of coals are mined. 
 
 MINES OF THE PYRENEES. 
 
 The Pyrenees and the mountains of Biscay, of the Asturias, and the north of Galieia, 
 which are their prolongation, are not very rich in deposits of ores. The only important 
 mines that occur there, are of iron ; which are widely spread throughout the whole 
 chain, except in its western extremity. We may mention particularly in Biscay, the 
 mine of Sommorostro, opened on a bed of red oxide of iron ; and in the province of 
 Guipuscoa, the mines of Mondragon, Oyarzun, and Berha, situated on deposits of sparry 
 iron. There are several analogous mines in Arragon and Catalonia. In the French 
 part of the Pyrenees, veins of sparry iron are worked which traverse the red sandstone 
 of the mountain Ustelleguy, near Baygorry, department of the Basses- Pyrenees. The 
 same department affords in the valley of Asson the mine of Haugaron, which consists of 
 a bed of hydrate of iron, subordinate to transition limestone. The deposit of hydrate 
 of iron, worked for an immemorial time at Rancie, in the valley of Viedessos, depart- 
 ment of the Arriege, occurs in a similar position. The ancient workings have been 
 very irregular and very extensive ; but the deposit is still far from being exhausted. 
 There are also considerable mines o sparry iron at Lapinouse, at the tower of Batera, 
 at Escaron, and at Fillols, at the foot of the Canigou, in the department of the Oriental 
 Pyrenees. The iron mines of the Pyrenees keep in activity 200 Catalanian forges. 
 Although there exists in these mountains, especially in the part formed of transition 
 rocks, a very great number of veins of lead, copper, cobalt, antimony, &c, one can 
 hardly mention any workings of these metals ; and among the abandoned mines, the 
 only ones which merit notice are, the mine of argentiferous copper of Baygorry, in the 
 department of the Low Pyrenees, the lead and copper mine of Aulus, in the valley of 
 the Erce, department of the Arriege, and the mine of cobalt, of the valley of Gistain, 
 situated in Arragon, on the southern slope of the Pyrenees. It is asserted, however, 
 that a lead mine is in actual operation near Bilboa in Biscay. The mines of plumbago 
 opened at Sahun.in Arragon, should not be forgotten. Analogous deposits are known 
 to exist in the department of the Arriege, but they are not mined. 
 
 MINES OF THE ALPS. 
 
 The mines of the Alps by no means correspond in number and richness with the 
 extent and mass of these mountains. On their eastern slope, in the department of the 
 
 Aa 2 
 
180 
 
 MINES. 
 
 high and the low Alps, several lead and copper mines are mentioned, all inconsiderable 
 and abandoned at the present time, with the exception of some workings of galena, 
 which furnish also a little graphite. 
 
 During some of the last years of the 18th century, there was mined at la Gardette 
 in the Oisans, department of the Isere, a vein of quartz which contained native gold 
 and auriferous pyrites ; but the product has never paid the expenses, and the mine has 
 been abandoned. The Oisans presented a more important mine, but it also has been 
 given up ; it was the silver mine of Allemont or Chalanches. The ore consisted of 
 lifferent mineral species more or less rich in silver, disseminated in a clay which filled 
 the clefts and irregular cavities in the middle of talcose and hornblende rocks. This 
 mine yielded annually towards the conclusion of the 1 8th century, so much as 2000 marcs 
 of silver ; along with some cobalt ore. Among the great number of mineral species, 
 which occurred in too small quantities to be worked to advantage, there was native 
 antimony, sulphuret of mercury, &c. The Oisans present, moreover, some rather 
 unproductive mines of anthracite. Mines of an analogous nature, but more valuable, 
 are in activity at the western foot of the Alps, at la Mothe, Notre-des- Vaux et Pidteville, 
 a few leagues S. E. of Grenoble. 
 
 From the entrance of the valley of the Oisans to the valley of the Arc in Savoy, there 
 occur on the N. W. slope of the Alps, a great many mines of sparry iron. The locality 
 of this ore is here very difficult to define. It appears to form sometimes beds or masses, 
 and sometimes veins amid the talcose rocks. Some is also found in small veins in the 
 first course of the calcareous formation which covers these rocks. These mines are very 
 numerous, the most productive occur united in the neighbourhood of Allevard, depart- 
 ment of the Isere, and of Saint Georges d' Iluretieres in Savoy. Those of Forneavx and 
 Laprat, in the latter country, are also mentioned. The irregularity of the mining 
 operations surpasses that of the deposits. The mines have been from time immemorial 
 in the hands of the inhabitants of the adjoining villages, who work in them, each on his 
 own account, without any pre-arrangement, or other rule than following the masses of 
 ore which excite hopes of the most considerable profit in a short space of time. What 
 occurs in almost every mine of sparry iron, is also to be seen here, most imprudent 
 workings. The mine called the Grande. Fosse, at Saint Georges cT Huretieres, is prolonged 
 without pillars or props, through a height of 130 yards, a length of 220 yards, an'd a 
 breadth equal to that of the deposit, which amounts in this place to from 8 to 13 yards; 
 thus a void space is exhibited of nearly 300,000 square yards. The sparry iron extracted 
 from these different mines supplies materials to 10 or 12 smelting furnaces, the cast 
 iron of which, chiefly adapted for conversion into steel, is manufactured in part in the 
 celebrated steel works of Rives, department of the Isere. There occurs in some parts of 
 the mines of Saint Georges d' Huretieres copper pyrites, which is smelted at Aiguebelle. 
 
 Savoy presents celebrated lead mines at Pescy and at Macot, 7 leagues to the E. of 
 Moutiers. Galena, accompanied with quartz, sulphate of baryta, and ferriferous car- 
 bonate of lime, occurs in mass in talcose rocks. The mine of Pescy had been restored 
 to activity by the French government, which established there a practical school of mines ; 
 and in its hands the mine produced annually as much as 440,000 libs, avoird. of lead, 
 and 2500 marcs of silver. It is now explored on account of the king of Sardinia ; but 
 it begins to be exhausted, and yields less products. That of Macot, opened a few years 
 ago, begins to give considerable returns. The mine of copper pyrites of Servoz in the 
 valley of the Arve, may also be mentioned. The ore occurs both in small veins, and 
 disseminated in a clay slate ; but the exploration is now suspended. Lastly, slightly 
 productive workings of anthracite are mentioned in several points of these mountains 
 and in the conterminous portions of the Alps. 
 
 There exist in Piedmont some small mines of argentiferous lead. The copper 
 mines of Allagne, and those of Ollomont, formerly yielded considerable quantities of 
 this metal. Their exploration is now on the decline. The manganese mines of Saint- 
 Marcel have few outlets; whence they have been feebly developed. Mines of plum- 
 bago, little worked, occur in the neighbourhood of Vinay and in the valley of Pellis, not 
 far from Fignerol. Some mines of auriferous pyrites have also been worked in this 
 district of country ; among others, those of Macugnaga, at the eastern foot of Monte- 
 Rosa. The pyrites of this mine afforded by amalgamation only 11 grains of gold 
 per quintal ; and this gold, far from being fine, contained £ of its weight of silver. 
 They became less rich in proportion as they receded from the surface. The explor- 
 ations of auriferous pyrites in Piedmont are now abandoned, or nearly so. The only 
 important mines in this country are those of iron. These generally consist of 
 masses of black oxide of iron, of a nature analogous to those of Sweden ; the principal 
 ones being those of Cogne and Traverselle, which are worked in open quarries. Some 
 others, less considerable, are explored by shafts and galleries. These ores are reduced 
 in 33 smelting cupolas, 55 Catalan forges, and 105 refinery hearths. The whole pro- 
 duce about 10,000 tons of bar iron. 
 
MINES. 
 
 181 
 
 There is a mine of black oxide of iron, at present abandoned, at Bovemier, near 
 Martigny, in the Valais. There is also another iron mine at Chamoissons, in a lofty 
 calcareous mountain on the right bank of the Rhone. The ore presents a mixture of 
 oxide of iron and some other substances, of which it has been proposed to make a new 
 mineral species, under the name of Chamoissite. 
 
 The district of the Grisons possesses iron mines with very irregular workings, situated 
 a few leagues from Coire. 
 
 The mountain of Falkenstein, in the Tyrol, formed of limestone and clay-slate, not far 
 from Schwatz, a little below Inspruck, in the valley of the Inn, contains mines of argen- 
 tiferous copper. At one of them, that of Kiitz-Piihl, the workings reached, in 1759, 
 according to the report of MM. Jars and Duhamel, nearly 1100 yards in depth; and 
 were reckoned the deepest in Europe. But it was intended to abandon them. Analo- 
 gous ores are explored in several other points of the same country. The most part of 
 the products of these mines are carried to the foundry of Brixlegg, 4 leagues from 
 Schwatz. The mines of the Tyrol furnished, on an average of years, towards 1759, 
 10,000 marcs of silver ; at anterior periods, their product had been double; but now it 
 is a little less. This region contains also gold mines whose exploration goes back a 
 century, and a half. They occur near the village of Zell, 8 leagues from Schwatz. 
 The auriferous veins traverse clay-slates, and quartz rocks. Lately, a deposit of oxide 
 of chrome, similar to that of the Ecouchets ( Saone and Loire) has been discovered in 
 the Tyrol. An unimportant mine of mercury has also been mentioned in that country, 
 near Brenner. 
 
 In the territory of Saltzburg there are some copper mines. In the environs of 
 Muerwinkel and of Gastein, some veins are worked for the gold they contain ; of which 
 the annual return is valued at 118 marcs of this metal. There is an inconsiderable mine 
 of quicksilver at Leogang. 
 
 In the Tyrol and in Saltzburg there are iron mines in a very active state; principally 
 those of Kleinboden, near Schwatz. But the portion of the Alps most abundant in 
 mines of this metal, is the branch stretching towards Lower Austria. We hnd here, 
 both in Styria and in Austria, a very great number of explorations of sparry iron. The 
 deposits of the ores of sparry iron of Eisenerz, Erzberg, Admont, and Vordenberg, 
 deserve notice. The latter are situated about 25 leagues S. W. of Vienna. 
 
 The southern flank of the Alps contains also a great many mines of the same kind, 
 from the Lago Maggiore to Carinthia. Those situated near Bergamo, and those of 
 Huttenberg and Waldenstein, in Carinthia, are especially mentioned. 
 
 All these mines of sparry iron are opened in the midst of rocks of different natures, 
 which belong to the old transition district of the Alps. They seem to have close 
 geological relations with those of Allevard. 
 
 The branch of the Alps which extends towards Croatia, presents important iron 
 mines, in the mountains of Adelsberg, 10 leagues S.W. from Lay bach in Carniola. 
 
 The iron mines just now indicated in the part of the Alps that forms a portion 
 of the Austrian states, supply materials to a great many smelting-works. In Styria 
 and in Carinthia, more than 400 furnaces or forges may be enumerated, whose annual 
 product is nearly 25,000 tons of iron. These two provinces are famous for the steel 
 which they produce, and for the steel tools which they fabricate, such as scythes, &c. 
 Carniola contains also a great many forges, and affords annually about 5000 tons of 
 iron. 
 
 There are mines of argentiferous copper analogous to those of the Tyrol, at Schlad- 
 ming in Styria, at Kirchdorf in Carinthia, at Agordo in the territory of Venice, and at 
 Zamabor in Croatia. The latter are remarkable for the great irregularity of the de- 
 posits, and for the richness of the copper pyrites that is mined; which produces 12 and 
 sometimes 27 per cent, of copper. There are some deposits of antimony, mined to a 
 trifling extent in Carinthia ; and there are a few cobalt mines in Styria, not more actively 
 worked. In the environs of Raibel, in Carinthia, mines of calamine exist, yielding 
 annually about 200 tons of this substance. Of late, some of it has also been explored 
 in Styria. 
 
 The limestones that cover the northern slopes of the Alps, present, like those of the 
 departments of the lower and upper Alps, several lead mines of little consequence. 
 They also include several celebrated mines of rock salt. 
 
 The analogous limestones which repose on the slopes of the Alps in Carinthia, and 
 in the neighbouring provinces, afford likewise lead mines, especially near Willach and 
 Bleyberg. These mines are very numerous, forming more than 500 arrondissemens 
 of concessions. They furnish annually about 1 800 tons of a lead too poor in silver to 
 pay the expense of extracting that precious metal. At the mines of Bleyberg, the 
 galena forms 14 beds or strata, inclined at an angle of from 40 to 50 degrees from the 
 horizon, and alternating with a like number of calcareous strata. The latter are 
 extremely full of shells. They of course belong to secondary limestone. 
 
182 
 
 MINES 
 
 The limestones surmounting the southern slope of the Alps, contain also some lead 
 mines; but the quicksilver mine of Idria, situated at the foot of the Alps, 10 leagues 
 N.W. of Trieste, is worthy of particular notice; it lies in a limestone which everything 
 leads us to refer to the zechstein, the most ancient of the secondary limestones. 
 
 The Apennines, which may be considered as a dependence of the Alps, present a 
 small number of mines. At Chiavary and Pignone, manganese is mined ; and at 
 the beginning of the 18th century a vein of mercury was worked at Levigliani in Tus- 
 cany. An antimonial mine is mentioned at Pereta in the marshes of Sienna. 
 
 Before quitting these regions, we ought to notice the iron mines of the isle of Elba. 
 They have been famous for 1 8 centuries ; Virgil denotes them as inexhaustible, and 
 supposes them to have been open at the arrival of Eneas in Italy. They are explored 
 by open quarries, working on an enormous mass of specular iron ore, perforated with 
 cavities bespangled with quartz crystals. The island possesses two explorations, called 
 Rio and Terra- Nuova ; the last having been brought into play at a recent period. 
 The average amount extracted per annum is 15,000 tons of ore, which are smelted in the 
 foundries of Tuscany, Liguria, the Roman states, the kingdom of Naples, and the island 
 of Corsica. 
 
 There has been worked for a few years a mine of chromite of iron, at Carrada, near 
 Gassino, department of the Var. 
 
 MINES SITUATED IN THE SCHISTOSE FORMATIONS OF THE BANKS OF THE RHINE, AND IN 
 
 THE ARDENNES. . 
 
 The transition lands, which form, in the N. W. of Germany and in Flanders, a 
 pretty extensive range of hills, include several famous mines of iron, zinc, lead, and 
 copper. The latter lie on the right bank of the Rhine, in the territories of Nassau 
 and Berg, at Baden, Augstbach, Rheinbreitenbach, and near Dillenburg. That of 
 Rheinbreitenbach yielded formerly 110,000 libs, avoird. of copper per annum, and 
 those of the environs of Dillenburg now furnish annually 176,000 libs. There are also 
 some mines of argentiferous lead in the same regions. The most remarkable are in 
 the territory of Nassau, such as those of Holzapfel, Pfingstiviese, Lcewenburg, and 
 Augstbach on the Wiede, and Ehrenthal on the banks of the Rhine, which all together 
 produce 600 tons of lead, and 3500 marcs of silver. To the above, we must add those 
 of the environs of Siegen and Dillenburg, in the territories of Berg. A little cobalt 
 is explored in the neighbourhood of Siegen, and some mines of the same nature are 
 mentioned in the grand duchy of Hesse- Darmstadt, and in the duchy of Nassau 
 Usingen. 
 
 But iron is the most important product of the mines on the right bank of the Rhine. 
 Veins of hydrate of iron, or brown hematite, are explored in a great many points of 
 Hessia, and the territory of Nassau, Berg, Marck, Tecklenbourg, and Siegen, along 
 with veins or masses of sparry iron, and beds of red oxide of iron. We may note par- 
 ticularly; 1. The enormous mass of sparry iron, known under the name of Stahlberg, 
 mined since the beginning of the 14th century in the mountain of Martinshardt, near 
 Miissen, where improvident excavations have occasioned, at, several times, considerable 
 downfallings of rubbish ; 2. The abundant and beautiful mines of hydrate of iron and 
 sparry iron on the banks of the Lahn and the Sayn, and among those of the mine of 
 Bendorf ; 3. The mine of Hohenkirchen in Hessia, where a powerful bank of manga- 
 nesiferous ore is worked, and where the mines are kept dry by a gallery more than one 
 thousand yards long, walled over its whole extent. These several mines supply a great 
 many iron works, celebrated for their steel, and for the objects of hardware, scythes, &c. 
 fabricated there. 
 
 The Prussian provinces of the left bank of the Rhine, the duchy of Luxembourg 
 and the Low Countries, include also many iron furnaces, of which a great number are 
 supplied, in whole or in part, by ores of hydrate of iron, occasionally zinciferous, 
 extracted from the transition rocks, where they form sometimes veins, and sometimes 
 also very irregular deposits. A portion is explored by open quarrying, and a portion 
 by underground workings. Some of these mines penetrate to a depth of 87 yards, and 
 galleries may be observed in them cut in the form of vaults, and timbered with hooped 
 stays. The Hundsriick, the Eiffel, and the territory of Luxembourg, present a great 
 many of them. 
 
 The Eiffel formerly possessed important lead mines. Some still exist, which are 
 feebly worked at Berncastle, 8 leagues below Treves, on the banks of the Moselle. 
 Those of Trarbach, situated two leagues lower, are now completely abandoned. The 
 same holds with those of Bleyalf, which were opened on veins incased in the grey- 
 wacke-slate, 3 leagues W. N. W. of Priim, not far from the line of separation of the 
 waters of the Moselle and the Meuse, in a district from which manufactures and com- 
 fort have disappeared since the mines were given up which sustained them. 
 
 More to the north a great many deposits of calamine occur. The most considerable, 
 
MINES. 
 
 1S3 
 
 and the one explored with most activity, is situated in the territory of Limburg 
 (kingdom of the Netherlands), and known under the Dame of the Great mountain. 
 It presents a mass about 45 yards wide, from 400 to 550 long, and of an unknown 
 depth. The first labours, undertaken several centuries ago by the Spaniards, were exe- 
 cuted by open quarrying, and pushed down 32 yards from the surface. The miners were 
 obliged to renounce this mode of operation, and have since penetrated to the depth of 
 88 yards by means of subterranean workings. From 50 to 60 men work in this exca- 
 vation, and extract annually from 700 to 800 tons of calamine, worth from 2400Z. 
 to 2700Z. In the adjacent parts of the Prussian territory, not far from Aix-la-Chapelle, 
 calamine is also mined, with ores of lead and iron, with which it is associated, in 
 deposits regarded by M. Bouesnel, as analogous to the vein of Vedrin, to be noticed 
 presently. The exploration is effected by means of small round shafts, from 34 to 44 
 yards deep, which arc often wooded only with flexible branches of trees, or a kind of 
 barrel -hoops. These workings may furnish annually from 1500 to 2000 tons of 
 calamine, to the brass factories of Stollberg. On the right bank of the Rhine, in the 
 country of la Marck, several small zinc mines furnish annually about 130 tons of cala- 
 mine to the brass manufactures of Iserlohn. 
 
 The lead mine of Vedrin, alluded to above, lies at some distance N. of Namur. It 
 is opened on a vein of galena nearly vertical,*which crosses from N. to S. a limestone 
 in nearly vertical strata, probably analogous into the limestone of Derbyshire. The 
 vein is from 4 to 15 feet thick, and is recognised through a length of half a league. 
 The mine, worked for two centuries, presents very extensive excavations ; particularly 
 a fine gallery of efflux. It has produced annually 900 tons of lead. At the present 
 day the mine of Vedrin, and some adjoining exploitations, afford per annum only about 
 200 tons of lead, and 700 marcs of silver. 
 
 MINES OF THE CALCAREOUS MOUNTAINS OF ENGLAND. 
 
 The limestone formation immediately subjacent to the coal measures, or the moun- 
 tain limestone, constitutes almost alone several mountainous regions of England and 
 Wales ; in which three districts very rich in lead mines deserve to be noted. 
 
 The first of these districts comprehends the superior parts of the valleys of the Tyne, 
 the Wear, and the Tees, in the counties of Cumberland, Durham, and York. Its 
 principal mines are situated near the small town of Alston-Moor, in Cumberland. 
 The veins of galena which form the object of the workings, traverse alternate beds of 
 limestone and sandstone; and are very remarkable for their becoming suddenly thin 
 and impoverished on passing from the limestone into the sandstone ; and for resuming 
 their richness, and usual size, on returning from the sandstone into the limestone. The 
 exploitations are situated in the flanks of considerably high hills, bare of wood, and 
 almost wholly covered with marshy heaths. The waters are drawn off by galleries of 
 efflux ; and the ores are dragged out by horses to the day. The galena extracted from 
 these mines is smelted by means of coal and a little peat, in furnaces of the Scotch con- 
 struction. The lead is very poor in silver ; and there is hardly a single hearth for the 
 purpose of eliminating this metal by cupellation. The mines of this district produce 
 annually 17,200 tons of lead, according to Mr. Taylor's statement, published in the 
 Geology of England and Wales, by Messrs. Conybeare and Phillips. There is more- 
 over a copper mine 2 leagues S. W. of Alston- Moor. The ore is a copper pyrites, 
 accompanied with galena in a very extensive vein, which does not appear to belong to 
 the same formation as the other veins of this region. 
 
 The second metalliferous district lies in the northern part of Derbyshire, and in the 
 conterminous parts of the neighbouring counties. The districts called the Peak and 
 King's- Field are the richest in workable deposits. The mines of Derbyshire are 
 getting exhausted ; they are very numerous, but in general inconsiderable. The 
 galena extracted from them is treated with coal in reverberatory furnaces ; but the 
 silver is not sought for. They yield annually 900 tons of lead ; with a certain quan- 
 tity of calamine, and a little copper ore. A vein of copper pyrites occurs at Ecton, in 
 Staffordshire, on the borders of Derbyshire. The veins of Derbyshire are famous for 
 the beautiful minerals which they have produced ; and particularly for the interruption 
 which they almost constantly suffer at the contact of the trap-rock, called toadstone, 
 which is intruded among the limestone. 
 
 The third metalliferous district is situated in Flintshire and Denbighshire, counties 
 forming the N. E. part of Wales. Next to Alston-Moor this is the most productive; 
 furnishing annually 6,900 tons of lead, and a certain quantity of calamine. The 
 galena is smelted in reverberatory furnaces, and affords a lead far from rich in silver, 
 which is therefore seldom subjected to cupellation. The mines occur partly in the 
 metalliferous limestone, and partly in several more ancient rocks. 
 
 To the S, E. of this district there exist still some lead mines in Shropshire. They 
 
184? 
 
 MINES. 
 
 lie, like the preceding, partly in the metalliferous limestone, and partly in the subjacent 
 rocks. They yield annually from 700 to 800 tons of lead. 
 
 Some mines of galena and calamine are mentioned in the Mendip hills, to the south 
 of Bristol ; but they seem to be for the present abandoned. 
 
 Besides the metallic mines just enumerated, the formation of the metalliferous lime- 
 stone presents, in England, especially in the counties of Northumberland and Cumber- 
 land, several coal mines, opened on coal strata included by the sandstone, which alter- 
 nates with the limestone. 
 
 MINES OF DAOURIA. 
 
 The name Daouria is given to a great region wholly mountainous, which extends 
 from the Baikal Lake to the Eastern Ocean. There is, perhaps, no other country in 
 the world so rich in deposits of lead ores, as the part of this district which extends from 
 the junction of the rivers Chilca and Argoun, whose united waters form the river 
 Amour, belonging to Russia. The mines opened here constitute the third arrondisse- 
 ment of the Siberian mines, called that of Nertchinsk, from the name of its capital, 
 which lies more than 1 800 leagues east of Saint Petersburg. 
 
 The ground of the metalliferous portion of Daouria is formed of granite, horns- 
 chiefer, and schists, on which reposes a gray limestone, sometimes siliceous and argil- 
 laceous, which contains a small number of fossils, and in which the veins of lead occur. 
 The plains of these regions, often salt deserts, exhibit remarkable sandstones and 
 pudding-stones; as also vesicular rocks of a volcanic aspect. It appears that the metal- 
 liferous limestone is much dislocated, and the lead veins are subject to several irregu- 
 larities, which render their exploitation difficult and uncertain. The mines lie chiefly 
 near the banks of the Chilca and the Argoun, in several cantons, at a considerable dis- 
 tance from one another ; wherefore it was requisite to build a great number of smelt- 
 ing furnaces. The want of wood has placed difficulties in the working of some of 
 them. The ore is galena, sometimes occurring in masses of several yards in diameter; 
 having commonly for vein-stones ores of iron and zinc, of which no use is made. The 
 galena itself, furnished by these mines in enormous quantities, receives a very differsnt 
 treatment from what it would do in a civilized country; for, though the lead which it 
 produces contains only from 6 to 10 gros (1 to 1^ ounce) of silver per quintal, it is for 
 it alone that these mines are worked. The litharge produced by the cupellation is 
 thrown away as useless ; so that heaps of it exist near the smelting-furnaces, says 
 M. Patrin, higher than the houses. Only an insignificant quautity of it is reduced to 
 lead for the uses of the country, or for those of the foundries in the arrondissement of 
 Koly wan. The silver extracted from the mines of Daouria, contains a very small pro- 
 portion of gold. M. Patrin says that their annual product was, towards the year 1784, 
 from 30 to 35 thousand marcs of silver. The exploitation of some of the mines of 
 Daouria goes back to the end of the 17th century. It had been commenced in some 
 points by the Chinese, who were not entirely expelled from this territory till the 
 beginning of the following century. A great part of the mines, however, has been 
 opened up since 1760. 
 
 Besides the lead mines, there are some unimportant mines of copper in Daouria, 
 and in different explorations of this region, arsenical pyrites, from which arscnious acid 
 is sublimed in factories established at Jutlack and at Tchalbutchinsky. 
 
 About 45 leagues to the south of Nertchinsk, the mountain of Odon-Tchelon occurs, 
 celebrated for the different gems or precious stones extracted from it. It is formed of 
 a friable granite, including harder nodules or balls which inclose topazes ; it is very 
 analogous to the topaz rock of Saxony. In this granite there are several veins filled 
 with a ferruginous clay, which contains a great quantity of wolfram, and many eme- 
 ralds, aqua marines, topazes, crystals of smoked quartz, &c. Multitudes of these 
 minerals have been extracted by means of some very irregular workings. The 
 mountain of Toutt-Kaltoui, situated near the preceding, offers analogous deposits. 
 The presence of wolfram had excited hopes that tin might be found in these moun- 
 tains ; hopes which have not hitherto been realized. There are some unworked 
 deposits of sulphuret of antimony in this country. 
 
 ON SOME OTHER LESS KNOWN MINE COUNTRIES. 
 
 There seem to exist in Brazil, besides the washings of the sands that produce the 
 diamonds, the precious stones, the platinum, and almost all the gold of this country, 
 some mines of gold, lead, and iron, opened up in very ancient geological formations ; 
 but there is no silver mine, which indicates a great difference between the metalliferous 
 deposits of this district and those of Spanish America. The lead mines occur parti- 
 cularly in the captainry of Minas-Geraes, canton of Abaite. Their exploitation has 
 been undertaken within a few years. The captainry of Minas-Geraes contains 
 extremely abundant deposits of black oxide of iron, and specular iron, which constitute 
 beds or enormous masses, forming sometimes entire mountains ; along with numerous 
 
MINES. 
 
 185 
 
 veins of hematite and red oxide of iron. Lately these have been opened up, and 
 smelting-houses have been established at Gaspar-Saarez. There are also iron mines 
 and foundries in the captainry of Saint- Paul. A mine of antimony occurs near Sahara, 
 in the captainry of Minas- Geraes. 
 
 In Africa, the inhabitants of the countries adjoining to the cape of Good Hope mine 
 and smelt copper and iron ; and the Congo produces considerable quantities of these two 
 metals. It is asserted that a great deal of copper exists in Abyssinia. On the banks 
 of the Senegal, the Moors and the Pouls fabricate iron in travelling forges. They em- 
 ploy as the ore the richest portions of a ferruginous sandstone, which seems to be a 
 very modern formation. Lastly, the kingdoms of Morocco and Barbary appear to 
 include several copper and iron mines. 
 
 The islands of Cyprus and Negropont, in the Mediterranean, were celebrated, in 
 former times, for their copper mines ; and several islands of the Archipelago presented 
 gold mines, now abandoned. The same thing may be said of Macedonia and Thrace. 
 The mountains of Servia and Albania contain iron mines ; and lead mines occur in 
 Servia. Natolia possesses iron and copper mines in the neighbourhood of Tokat. 
 Some also occur in Arabia and in Persia ; and in the territories round Caucasus, the 
 kingdom of Imeretta is distinguished for its iron mines. The celebrity of the Damas- 
 cus sabres attests the good quality of the products of some of the mines. Persia 
 includes, besides, mines of argentiferous lead at Kervan, a few leagues from Ispahan ; 
 and Natolia furnishes orpiment. 
 
 Some iron and copper mines have been mentioned in Tartary. Thibet passes for 
 being rich in gold and silver mines. China produces a great quantity of iron and mer- 
 cury, as well as white brass (tombac), which is much admired. The copper mines of this 
 empire lie principally in the province of Yu Nan and the island Formosa. Japan, like- 
 wise, possesses copper mines in the provinces of Kijunack and Sarunga. They seem to 
 be abundant ; at a period not far back, they exported their products to Europe. Japan 
 presents, moreover, mines of quicksilver. China and Japan contain also mines of gold, 
 silver, tin, red sulphuret of arseruc, &c. Large deposits of the latter ore (realgar) are 
 said to occur in the tin mine of Kian-Fu in China. But in that empire, as in Europe, 
 coal is the most important of the mining products. This combustible is explored, es- 
 pecially in the environs of Pekin, and in the northern parts of the empire. 
 
 Iron mines exist in several points of the Burman empire, and of Hindostan. Near 
 Madras, there exist excellent ores of sparry iron, and black oxide, analogous to the Swedish 
 ores. The Indian natural steel, named Wootz, has been held in considerable estimation 
 among some eminent London cutlers ; but the iron and steel recently manufactured upon 
 a great scale near Madras, by Messrs. Heath and Co,, from the crystallized magnetic 
 ore of that country, will probably ere long rival, and eventually supersede in Europe the 
 product of the Dannemara forges. The islands of Macassar, Borneo and Timor, include 
 copper mines. As to the tin obtained from the island of Banca, from the penin- 
 sula of Malacca, and several other points of southern Asia, it proceeds entirely from the 
 washing of sands. The same is undoubtedly true of the gold furnished by the Philip- 
 pine isles, Borneo, &c. It appears, however, that mines of gold and silver are worked 
 in the island of Sumatra. 
 
 MINES OF THE SECONDARY ROCK FORMATIONS. 
 
 The most important mines of the secondary rocks, and perhaps of all minerals 
 whatsoever, are those worked in the most ancient of these strata, in the coal-measnres. 
 
 The British Islands, France, and Germany present several groups of small mountains 
 primitive on the ridge, and transition on the flanks ; in the sinuosities between which 
 deposits of coal occur. The principal of these have become great centres of manufac- 
 tures ; for Glasgow, Newcastle, Sheffield, Birmingham, Saint- Etienne, &c, owe their 
 prosperity and their rapid enlargement to the coal, raised, as it were, at their gates in 
 enormous quantities. Wales, Flanders, Silesia, and the adjacent parts of Gallicia, owe 
 equally to their extensive collieries a great portion of their activity, their wealth, and 
 their population. Other coal districts, less rich, or mined on a less extended scale, have 
 procured for their inhabitants less distinguished, but by no means inconsiderable, advan- 
 tages ; such, for examples in Great Britain, are Derbyshire, Cheshire, Lancashire, 
 Shropshire, Warwickshire, the environs of Bristol, &c. ; some parts of Ireland ; in 
 France, Litry department of Calvados, Comanterie, Saint- Georges- Chatelaison, Aubin, 
 Alais, le Creusot; Ronchamps, in the Prussian provinces of the left bank of the Rhine ; 
 the environs of Saarebriick ; several points of the north of the territory of Berg and 
 Lamarck, of Mansfeld, of Saxony, Hungary, Spain, Portugal, the United States, &c. 
 
 We need not enter here into ampler details on coal mines, reserving these particulars 
 for the article Pitcoal. 
 
 Nature has deposited alongside of coal an ore, whose intrinsic value alone is very 
 small, but whose abundance in the neighbourhood of fuel becomes extremely precious to 
 
 Bb 
 
186 
 
 MINES. 
 
 man ; we allude to the clay-ironstone of the coal-measures. It is extracted in enormous 
 quantities from the coal-basins of Scotland, Yorkshire, Staffordshire, Shropshire, and 
 South Wales. 
 
 Much of it is also raised from the coal strata of Silesia ; and the French entertain 
 hopes of finding a supply of this necessary ore in their own country. The iron- works 
 of England, which are supplied almost entirely from this iron-stone reduced with the 
 coke 01 coal, pour annually into commerce more than one million tons of cast and bar 
 iron, the value of which has been estimated at eight millions, sterling; an amount fully 
 equal to the product of all the mines of Spanish America. 
 
 The shale or slate-clay of the coal-measures contains sometimes a very large quantity 
 of pyrites, which, decomposing by the action of air, with or without artificial heat, pro- 
 duces sulphate of iron and sulphate of alumina ; whence copperas and alum are manu- 
 factured in great abundance. 
 
 The lead mines of Bleyberg and Gemiind, near Aix-la- Chapelle, are explored in a 
 sandstone referred by many geologists to the red sandstone. The ore consists principally 
 of nodules of galena disseminated in this rock. They are very abundant, and of very 
 easy exploration. These mines produce annually from 700 to 800 tons of lead, which 
 does not contain silver in sufficient proportion to be worth the extracting. 2000 tons 
 of ore are prepared and sold in the form of black lead dust (alquifoux). 
 
 The manganese mines worked in the open air near Exeter in England, occur in a 
 sandstone analogous to the red. 
 
 The calcareous formation which surmounts the coal- sandstone, called oy geologists 
 zechstein, magnesian limestone, and older Alpine limestone, contains different deposits of 
 metallic ores ; the most celebrated being the cupreous schist of Mansfeldt, a stratum of 
 calcareous slate from a few inches to two feet thick, containing copper pyrites in suffi- 
 cient quantity to afford 2 per cent, of the Aveight of the ore of an argentiferous copper. 
 This thin layer displays itself in the north of Germany over a length of eighty leagues, 
 from the coasts of the Elbe to the banks of the Rhine. Notwithstanding its thinness and 
 relative poverty, skilful miners have contrived to establish, on different points of this slate, 
 a number of important explorations, the most considerable being in the territory of 
 Mansfeldt, particularly near Rottenburg. They produce annually 2000 tons of copper, 
 and 20,000 marcs of silver. We may also mention those of Hessia, situated near Frank- 
 enberg, Bieber, and Riegelsdorf. In the latter, the cupreous schist and its accompa- 
 nying strata, are traversed by veins of cobalt, mined by the same system of underground 
 workings as the schist. These operations are considerable ; they extend, in the direction 
 of the strata, through a length of 8700 yards, and penetrate downwards to a very 
 great depth. Three galleries of efflux are to be observed ; two of which pour their 
 waters into the Fulde, and the third into the Verra. .One of them runs about 20 yards 
 below the most elevated point of the workings. These mines have been' in activity 
 since the year 1530. Analogous mines exist near Saalfeld in Saxony. 
 
 To the same geological formation must probably be referred the limestone which con- 
 tains the sparry iron mine of Schmalcalden at the western foot of Thuringerwald, where 
 there has been explored from time immemorial a considerable mass of this ore known 
 by the name of Stahlberg. The working is executed in the most irregular manner, and 
 has opened up enormous excavations ; whence disastrous ruins have taken place in the 
 mines. It furnishes annually 4500 tons of ore, which keep in play a great number of 
 furnaces, where a deal of iron and steel is manufactured. 
 
 At Tarnowitz, 14 leagues S. E. of Oppeln in Siberia, the zechstein contains, in some 
 of its strata, considerable quantities of galena and calamine ; into which, mines have 
 been opened, that yield annually from 600 to 700 tons of lead, 1000 to 1 100 marcs of 
 silver, and much calamine. Mines of argentiferous lead are noticed at Olkutch and 
 Jaworno in Gallicia, about 6 leagues N. E. of Cracow, and 15 leagues E. N. E. of 
 Tarnowitz. Their position seems to indicate that they belong to the same formation ; 
 and possibly those of Willach and Bleyberg in Carinthia have the same locality. 
 
 There has been discovered lately near Confolens in the department of la Charente, in a 
 secondary limestone, calcareous beds, and particularly subordinate beds of quartz, which 
 contain considerable quantities of galena. At Figeac also, in the department of le Lot, 
 deposits of galena, blende, and calamine occur in a secondary limestone. At la Voulte 
 on the banks of the Rhone, there is mined, in the lower courses of the limestones that 
 constitute a great portion of the department of the Ardeche, a powerful bed of iron 
 ore. 
 
 It is in the zechstein, or in the sandstones, and trap rocks of nearly the same age, that 
 the four great deposits of the sulphuret of mercury, of Idria, the Palatinate, Almaden, 
 and Huancavelica, are mined. 
 
 The formation which separates the zechstein from the lias (calcaire a graphites'), called 
 new red sandstone and red marl in England, and bunter-sandstein, muschelkalk, and 
 quadersandstein in Germany, presents hardly any important mines except those of rock 
 
MORTAR, HYDRAULIC. 
 
 187 
 
 salt ; which enrich it, not only in the centre of Europe, as in Cheshire, at Vic, Wie- 
 liczka, Bochnia, and Salzbourg, but in many other parts of the world. 
 
 The lias contains often very pyritous lignites, which are mined in many places, and 
 particularly at Whitby and Guisborough in Yorkshire, for the manufacture^ alum and 
 copperas. 
 
 The oolitic limestones contain strata of iron ore, which are mined in some districts of 
 France. 
 
 The iron sand- ( Hastings sand) beneath the chalk formation, is often so strongly im- 
 bued with iron as to be worth the working. 
 
 The lowest beds of the chalk contain iron pyrites, which has become the object of an 
 important exploration at Vissans on the southern coast of the Pas-de- Calais, where it is 
 converted into sulphate of iron. The waves turn the nodules out of their bed, and roll 
 them on the shore, where they are picked up. 
 
 If the chalk be poor in useful minerals, this is not the case with the plastic clay 
 formation above it ; for it contains important mines. In it are explored numerous beds 
 of lignite (wood-coal), either as fuel or a vitriolic earth. From these lignite deposits, 
 also, the yellow amber is extracted. 
 
 The other tertiary formations present merely a few mines of iron and bitumen. 
 
 Several of the secondary or tertiary strata contain deposits of sulphur, which are mined 
 in various countries. 
 
 The formations of a decidedly volcanic origin afford few mining materials, if we ex- 
 cept sulphur, alum, and opals. 
 
 MINES OF THE ALLUVIAL STRATA. 
 
 This formation contains very important mines, since from it are extracted all the dia- 
 monds, and almost all the precious stones, the platinum, and the greatest part of the gold, 
 with a considerable portion of the tin and iron. The diamond mines are confined 
 nearly to Brasil, and to the kingdoms of Golconda and Visapour in the East Indies. 
 
 MORTAR, HYDRAULIC. Professor Kuhlmann, of Lisle, obtained a patent in 
 April 1841, in the name of Mr. Newton, for certain improvements in the manufacture 
 of lime-cement and artificial stone ; and of which he gave me a sample, possessed of a 
 hardness and solidity fit for the sculptor. 
 
 In operating by the dry method, instead of calcining the limestone with sand and 
 clay alone, as has been hitherto commonly practised, the inventor introduces a small 
 quantity of soda or, preferably, potash, in the state of sulphate, carbonate, or muriate ; 
 salts susceptible of forming silicates when the earthy mixture is calcined. The alkaline 
 salt, equal in weight to about one fifth that of the lime, is introduced in solution among 
 the earths. 
 
 All sorts of lime are made hydraulic, in the humid way, by mixing slaked lime with 
 solutions of common alum or sulphate of alumina ; but the best method consists in 
 employing a solution of the silicate of potash, called liquor of flints, or soluble glass, to 
 mix in with the lime, or lime and clay. An hydraulic cement may also be made 
 which will serve for the manufacture of architectural ornaments, by making a paste of 
 pulverized chalk, with a solution of the silicate of potash. The said liquor of flints 
 will likewise give chalk and plaster a stony hardness, by merely soaking them in it 
 after they are cut or moulded to a proper shape. On exposure to the air, they get 
 progressively indurated. Superficial hardness may be readily procured by washing 
 over the surface of chalk, &c, with liquor of flints, by means of a brush. This method 
 affords an easy and elegant method of giving a stony crust to plastered walls and ceil- 
 ings of apartments ; as also to statues and busts, cast in gypsum, mixed with chalk. 
 
 The essential constituents of every good hydraulic mortar, are caustic lime and 
 silica ; and the hardening of this compound under water consists mainly in a chemical 
 combination of these two constituents through the agency of the water, producing a 
 hydrated silicate of lime. But such mortars may contain other bases besides lime, as 
 for example clay and magnesia, whence double silicates of great solidity are formed ; 
 on which account dolomite is a good ingredient of these mortars. But the silica must 
 be in a peculiar state for these purposes ; namely, capable of affording a gelatinous paste 
 with acids ; and if not so already, it must be brought into this condition, by calcining 
 it along with an alkali or an alkaline earth, at a bright red heat, when it will dissolve, 
 and gelatinize in acids. Quartzose sand, however fine its powder may be, will form 
 no water mortar with lime ; but if the powder be ignited with the lime, it then 
 becomes fit for hydraulic work. Ground felspar or clay form with slaked lime no 
 water cement ; but when they are previously calcined along with the lime, the mixture 
 becomes capable of hardening under water. 
 
 The mastic called Hamelin's, and so much employed in London, is composed of 
 ground Portland stone (roe stone), sand and litharge in the proportion of 62 of the 
 first, 35 of the second, and 3 of the third, in 100 parts; but other proportions will also 
 
 B b 2 
 
188 
 
 MUSQUET. 
 
 answer the purpose. I find that chalk will not make a good mastic ; being too 
 compact to permit the air to insinuate between the pores, and to produce the con- 
 cretion of the linseed oil, with which the above mixture is worked up and applied. 
 This mastic soon acquires great hardness, and is totally impervious to water. The 
 surface to which it is to be applied must be dry, and smeared over with linseed oil. 
 Considerable dexterity is required to make good work with it. The fine dust of 
 sandstone alone, mixed with 10 or 12 per cent, of litharge and 7 per cent, of linseed 
 oil, forms an excellent mastic. 
 
 Limestone, which contains as much as 10 per cent, of clay, comports itself after 
 calcination, if all the carbonic acid be expelled, just as pure limestone would do. 
 When it is less strongly burned, it affords however a mass which hardens pretty 
 speedily in water. If the argillaceous proportion of a marl amounts to 1 8 or 20 per 
 cent., it still will slake with water, but it will absorb less of it, and forms a tolerably 
 good hydraulic mortar, especially-^ a little good Roman cement be added to it. 
 
 When the proportion of clay is 25 or 30 per cent, after burning, it heats but little 
 with water, nor does it slake well, and must therefore be ground by stampers or an 
 edge millstone, when it is to be used as a mortar. This kind of marl yields commonly 
 the best water cement without other addition. Should the quantity of clay be 
 increased farther, as up to 40 per cent., the compound will not bear a high or long- 
 continued heat without being spoiled for making hydraulic mortar after grinding to 
 powder. When more strongly calcined, it forms a vitriform substance, and should, 
 after being pulverized, be mixed up with good lime, to make a water mortar. If the 
 marls, in any locality, differ much in their relative proportions of lime and alumina, 
 as may be readily ascertained by the use of my lime-proof apparatus (see Appendix), 
 then the several kinds should be mixed in such due proportions as to produce the 
 most speedily setting, and most highly indurating hydraulic cement. 
 
 MUNDICK. The name given by the Cornish miners to iron or arsenical pyrites. 
 
 MUSK. The musk deer, from the male of which animal species the bag containing 
 this valuable drug is obtained, is a native of the mountainous Kirgesian and Langorian 
 steppes of the Altai, on the river Irtish, extending eastwards as far as the river Jenesi 
 and Lake Baikal ; and generally of the mountains of Eastern Asia, between 30° and 
 60° of N. L. Two distinct kinds of musk are known in commerce, the first being the 
 Chinese Tonquin, Thibetian, or Oriental, and the Siberian or Russian. The Chinese 
 is regarded by Dr. Goebel as the result of ingenious adulterations of the genuine article 
 by that crafty people. The Russian musk is genuine, the bags never being opened, 
 are consequently never sewn, nor artificially closed, like those imported into London 
 from China. The former is sometimes so fresh, that moisture may be expressed from 
 the bag by cutting through its fleshy side. The interior mass is frequently of a soft 
 and pappy consistence ; but the surface of the bag is perfectly dry. The Chinese bags 
 are found invariably to have been opened and again glued together, more or less neatly ; 
 though sometimes the stitches of the sewing are manifest. Mr. Dyrssen, an eminent 
 merchant at St. Petershurgh, states that during the many years he has been in the trade, 
 although he has received at a time from 100 to 200 ounces from London, yet in no 
 case whatever has he met with a bag which had not been opened, and closed with more 
 or less ingenuity. The genuine contents seem to have been first removed, modified, 
 and replaced. M. Guibourt gives the following as the constituents of a Chinese musk 
 bag: 1. water; 2. ammonia ; 3. solid fat or stearine; 4. liquid fat or elaine ; 5. cho- 
 lesterine; 6. acid oil, combined with ammonia ; 7. volatile oil ; 8 — 10. hydrochlorates 
 of ammonia, potassa, and lime; 11. an undetermined acid ; 12. gelatin; 13. albumen; 
 14. fibrin; 15. carbonaceous matter soluble in water; 16. calcareous salt; 17. carbo- 
 nate of lime ; 1 8. hairs and sand. 
 
 From June 1841 to June 1842, a duty of 6d. per oz. was paid at the port of London 
 alone upon 969 ounces of musk. The prices of grain musk of the best quality (the 
 matter without the bag) varies from 60s. to 95s. per oz. 
 
 There is a superior musk imported now from the United States, which is nearly free 
 from the carbonate of lime, so abundant in the bags of the Siberian musk. 
 
 MUSQUET. It is now fourteen years since the Hon. Board of Ordnance, with 
 the view of introducing the use of percussion fire-arms into the British Army, em- 
 ployed me to investigate experimentally the best mode of preparing the priming 
 powder for that purpose. The result of these experiments was presented in a report, 
 the substance of which is given under the article " Fulminate" in the Dictionary. During 
 this long interval, Mr. Lovell, inspector of small arms for her Majesty's service, , and 
 director of the Royal Manufactory, at Enfield Chase, has directed his ingenious mind 
 to the construction of a sure, simple, and strong musquet, with which, under his able 
 superintendence, the whole of her Majesty's soldiers are now provided. He has also 
 furnished them with a short, but clear set of instructions for the cleaning and manage- 
 ment of these excellent arms, illustrated by a series of wood engravings. From this 
 little work the following notice is copied. 
 
MUSQUET. 
 
 189 
 
 Fig. 94. The barrel, reduced to one-seventh size, a, the breech ; b, the nipple-seat 
 or lump ; c, the back-sight ; d, the back loop ; e, the middle loop ; /, the swivel-loop ; 
 g, the front-loop with the bayonet-spring attached ; h, the front sight ; i, the muzzle. 
 
 Fig. 95. The breech-pin, half size, a, the tang ; 6, the neck; c, the screw-threads ; 
 d, the face. 
 
 0 
 
 94 
 
 98 
 
 or 
 
 96 
 
 97 
 
 Fig. 96. The bayonet-spring, two ways, half size, a, the shank ; 6, the neck ; c, 
 the hook ; d, the mortice. 
 
 Fig. 97. The nipple, full size, a, the cone ; b, the squares ; c, the shoulder ; d, 
 the screw-threads ; e, the touch-hole. 
 
 2<%. 98. The rammer, reduced to one-seventh size, a, the head ; b, the shaft ; e, 
 the screw-threads. 
 
190 
 
 OILS. 
 
 Fig. 99. The lock outside, half size. a, the plate ; b, the cock ; c, the tumbler-pin 
 d, the hollow for the nipple seat. 
 
 Fig. 100. The lock inside, half size, showing all the parts in their places with the cock 
 down at bearer, a, the main-spring ; b, the sear-spring ; c, the sear ; d, the tumbler ; 
 
 e, the bridle; /, the main-spring-pin; g, the sear-pin; h, the sear-spring-pin; i, the 
 bridle-pin. 
 
 N. 
 
 NITRE (Saltpetre), and NITRATE OF SODA (Cubic nitre), imported for 
 home consumption in 1839, 314,543 cwts. ; in 1840, 369,204; duty 6d. per cwt. 
 NITROMETER. See Appendix. 
 
 NUTMEGS; imported for consumption in 1839, 133,470 lbs. ; in 1840, 118,554; 
 duty from British possessions, 2s. 6d. ; from foreign, 3s. 6d. per lb. 
 
 0. 
 
 OIL, COCOA-NUT; imported for consumption in 1839, 15,153 cwts. ; in 1840, 
 37,269; duty, Is. 3d. per cwt. 
 
 OIL, OLIVE; imported for consumption in 1839, 1,806,178 gallons; in 1840, 
 1,985,902; duty 8d per gallon. 
 
 OIL, PALM; imported for consumption in 1839, 262,910 cwts. ; in 1840, 314,881 ; 
 duty, Is. 3d. per cwt. 
 
 OIL, train, spermaceti, and blubber; imported for consumption in 1839, 21,438 
 tuns; in 1840, 19,955, of British fishing, Is. per tun; of foreign fishing, 26/. 12s. 
 per tun. 
 
 The numerous uses of unctuous oils give importance to their preparation, as articles 
 of food, or for burning in lamps, and for the manufacture of soaps, &c. The seeds 
 
OILS. 
 
 191 
 
 most productive of oil are those of colza (a species of cabbage, brassica arvensis), 
 rape, mustard, sesamum, poppy, linseed, hemp, and beechmast. Nuts afford an oil 
 that is much esteemed for certain purposes, and may be easily obtained by pressure. 
 The following Table indicates the quantities of oil which can be extracted from 
 different fruits, and some other substances : — 
 
 100 Parts of each. 
 
 Oil per Cent. 
 
 100 Parts of each. 
 
 Oil per Cent. 
 
 Walnuts - - - 
 
 40 to 70 
 
 Wild mustard seed - 
 
 30 
 
 Castor-oil seeds 
 
 62 
 
 Camelina seed 
 
 28 
 
 I I n 7 1 >1 tilled _ 
 
 fif> 
 
 AVeld seed - - - 
 
 Oft +r\ O /? 
 
 ijy to Jo 
 
 Garden cress seed - — 
 
 3D 10 DO 
 
 Gourd seed - 
 
 25 
 
 Sweet almonds » - 
 
 ■4U to o4 
 
 Lemon seed - 
 
 25 
 
 Bitter almonds — — 
 
 Zo lO 4o 
 
 Onocardium acanthe, or 
 
 
 Poppy seeds - - - 
 
 56 to 63 
 
 bear's foot - 
 
 25 
 
 Oily radish seed 
 
 50 
 
 Hemp seed - 
 
 1 4 to 25 
 
 Sesamum (jugoline) 
 
 50 
 
 Linseed - 
 
 11 to 22 
 
 Lime-tree seeds 
 
 48 
 
 Black mustard seed 
 
 15 
 
 Cabbage seed - - - 
 
 30 to 39 
 
 Beech mast - - - 
 
 15 to 17 
 
 White mustard 
 
 36 to 38 
 
 Sunflower seeds 
 
 15 
 
 Rape, colewort, and Swe- 
 
 
 Stramonium, or thorn- 
 
 
 dish turnip seeds - 
 
 33-5 
 
 apple, seeds 
 
 15 
 
 Plum kernels - 
 
 33-3 
 
 Grape-stones - 
 
 14 to 22 
 
 Colza seed 
 
 36 to 40 
 
 Horse-chestnuts 
 
 1 -2 to 8 
 
 Rape seed - 
 
 30 to 36 
 
 St. Julian Plum 
 
 18 
 
 Euphorbium (spurge seed) 
 
 30 
 
 
 
 To obtain the above proportions of oil, the fruits must be all of good quality, 
 deprived of their pods, 'coats, or involucra, and of all the parts destitute of oil, which 
 also must be extracted in the best manner. 
 
 The following Table is given by M. Dumas, as exhibiting the practical results of the 
 French seed oil manufacturers : — 
 
 
 Weight per Hectolitre. 
 
 Produce in Litres. 
 
 Summer Colza - - - 
 
 54 to 65 kilogs. 
 
 21 to 25 
 
 Winter Colza - 
 
 56 to 70 
 
 
 25 to 28 
 
 Rape seed - 
 
 55 to 68 
 
 
 23 to 26 
 
 Camelina seed - 
 
 53 to 60 
 
 
 20 to 24 
 
 Poppy seed 
 
 54 to 62 
 
 
 22 to 25 
 
 Madia sativa - 
 
 40 to 50 
 
 
 12 to 15 
 
 Beech mast - 
 
 42 to 50 
 
 
 12 to 15 
 
 Hemp seed - - - 
 
 42 to 50 
 
 
 12 to 15 
 
 Linseed - - - - 
 
 By sample 
 
 67. 
 
 10 to 12 
 
 Stripped walnuts - 
 
 From 100 kilogs. 
 
 46 to 50 
 
 Sweet almonds - 
 
 — 100 
 
 
 44 to 48 
 
 Olives - - - - 
 
 — 100 
 
 
 10 to 12 • 
 
 Colza, rapeseed, and cameline oils are employed for lamps ; poppy, madia sativa, 
 are employed, when recent, as articles of food — or for soaps and paintings ; hemp- 
 seed and linseed for painting, soft soaps, and for printers' ink; walnut oil, for food, 
 painting, and lamps ; olive oil, for food, soaps, lamps. 
 
 In extracting oil from seeds, two processes are required — 1st, trituration; 2d, ex- 
 pression ; and the steps are as follows : — 
 
 1. Bruising under revolving heavy-edge millstones, in a circular bed, or trough of 
 iron, bedded on granite. 
 
 2. Heating of the bruised seeds, by the heat either of a naked fire or of steam. 
 
 3. First pressure or crushing of the seeds, either by wedges, screw, or hydraulic 
 presses. 
 
 4. Second crushing of the seed cakes of the first pressure. 
 
 5. Heating the bruised cakes ; and, 6. A final crushing. 
 
 The seeds are now very generally crushed, first of all between two iron cylinders 
 revolving in opposite directions, and fed in from a hopper above them ; after which they 
 yield more completely to the triturating action of the edge stones, which are usually 
 hooped round with a massive iron ring. A pair of edge millstones of about 7 or 1\ 
 feet in diameter, and 25 or 26 inches thick, weighing from 7 to 8 tons, can crush, in 
 12 hours, from 2\ to 3 tons of seeds. The edge-milistones serve not merely to grind 
 
192 
 
 OILS. 
 
 the seeds at first, but to triturate the cakes after they have been crushed in the press. 
 Old dry seeds sometimes require to be sprinkled with a little water to make the oil 
 come more freely away ; but this practice requires great care. 
 
 The apparatus for heating the bruised seeds consists usually of cast-iron or copper 
 pans, with stirrers moved by machinery. Figs. 101, 102, 103, 104. represent the heaters 
 by naked fire, as mounted in Messrs. Maudsley and Field's excellent seed crushing 
 mills, on the wedge or Dutch plan. 
 
 Fig. 101. is an elevation, or side view of the fire-place of a naked heater; fig. 102. 
 is a plan, in the line UU of fig. 101. Fig. 103. is an elevation and section parallel to 
 the line VV of fig. 102. Fig. 104. is a plan of the furnace, taken above the grate 
 of the fire place. 
 
 A, fire-place shut at top by the cast-iron plate B. ; called the fire-plate. 
 
 C, iron ring-pan, resting on the plate B, for holding the seeds ; which is kept in its 
 place by the pins or bolts a. 
 
 D, funnels, britchen, into which by pulling the ring-case c, by the handles b, b, the 
 seeds are made to fall, from which they pass into bags suspended to the hooks c. 
 
 E, fig. 103., the stirrer which prevents the seeds from being burned by continued 
 contact with the hot plate. It is attached by a turning-joint to the collar F, which 
 
 t 
 
OILS. 
 
 193 
 
 turns with the shaft G, and slides up and down upon it H, a bevel wheel, in gear 
 with the bevel wheel I, and giving motion to the shaft G. 
 
 K, a lever for lifting up the agitator or stirrer E. e, a catch for holding up the 
 lever K, when it has been raised to a proper height. 
 
 Fig. 105., front elevation of the wedge seed-crushing machine, or wedge-press. 
 Fig. 106. section, in the line XX, of fig. 107. 
 
 106 y 105 
 
 Fig. 107., horizontal section, in the line YY, of fig. 106. 
 
 107 
 
 A, A, Upright guides, or frame-work of wood. 
 
 B, B, Side guide-rails. 
 
 D, Driving stamper of wood, which presses out the oil ; C, spring stamper, or re- 
 lieving wedge, to permit the bag to be taken out when sufficiently pressed. E is the 
 lifting shaft, having rollers, b, b, b, b, fig. 106., which lift the stampers by the cams, 
 a, a, fig. 106. F is the shaft from the power-engine, on which the lifters are fixed. 
 
 G, is the cast iron press-box, in which the bags of seed are placed for pressure, later- 
 ally by the force of the wedge. 
 
 C c 
 
194 
 
 OILS, ADULTERATION OF. 
 
 o,figs. 105. and 108.; the spring, or relieving wedge. 
 e, lighter rail ; d, lifting-rope to ditto. 
 /»/»/»/» flooring overhead. 
 
 g, Jigs. 105. and 108.; the back iron, or end-plate minutely perforated. 
 
 h, the horse-hair bags (called hairs), containing the flannel bag, charged with seed ; 
 i, the dam-block ; m, the spring wedge. 
 
 Fig. 107. A, upright guides; C, and D, spring and driving stampers; E, lifting 
 roller ; F, lifting shaft ; a, a, cams of stampers. 
 
 Fig. 108., a view of one set of the wedge-boxes, or presses ; supposing the front of 
 them to be removed. 
 
 Fig. 108.; o, driving wedge; g, back 
 iron ; h, hairs ; i, dam-block ; k, speer- 
 ing or oblique block, between the two 
 stampers; I, ditto; n, ditto; m, spring 
 wedge. 
 
 When, in the course of a few minutes, 
 the bruised seeds are sufficiently heated 
 in the pans, the double door F F is with- 
 drawn, and they are received in the bags, 
 below the aperture G. These bags are 
 made of strong twilled woollen cloth, 
 woven on purpose. They are then 
 wrapped in a hair-cloth, lined with 
 leather. 
 
 The first pressure requires only a dozen blows of the stamper, after which the pouches 
 are left alone for a few minutes till the oil has^had time to flow out ; in which interval 
 the workmen prepare fresh bags. The former are then unlocked, by making the stamper 
 fall upon the loosening wedge or key, m. 
 
 The weight of the stampers is usually from 500 to 600 pounds ; and the height from 
 which they fall upon the wedges is from 16 to 21 inches. 
 
 Such a mill as that now described, can produce a pressure of from 50 to 75 tons 
 upon each cake of the following dimensions : — 8 inches in the broader base, 7 inches 
 in the narrower, 18 inches in the height ; altogether nearly 140 square inches in surface, 
 and about | of an inch thick. 
 
 OILS, ADULTERATION OF. M. Heidenreich has found in the application 
 of a few drops of sulphuric acid to a film of oil, upon a glass plate, a means of ascer- 
 taining its purity. The glass plate should be laid upon a sheet of white paper, and a 
 drop of the acid let fall on the middle of ten drops of the oil to be tried. 
 
 With the oil of rape-seed and turnip -seed, a greenish blue ring is gradually formed at 
 a certain distance from the acid, and some yellowish brown bands proceed from the 
 centre. 
 
 With oil of black mustard, in double the above quantity, also a bluish green colour. 
 With whale and cod-oil, a peculiar centrifugal motion, then a red colour, increasing 
 gradually in intensity ; and after some time, it becomes violet on the edges. 
 With oil of cameline, a red colour, passing into bright yellow. 
 Olive-oil, pale yellow, into yellowish green. 
 
 Oil of poppies and sweet almonds, canary yellow, passing into an opaque yellow. 
 Of linseed, a brown magma, becoming black. 
 Of tallow or oleine, a brown colour. 
 
 In testing oils, a sample of the oil imagined to be present should be placed alongside 
 of the actual oil, and both be compared in their reactions with the acid. A good way 
 of approximating to the knowledge of an oil is by heating it, when its peculiar odour 
 becomes more sensible. 
 
 Specific gravity is also a good criterion. The following table is given by M. Hei- 
 denreich : — 
 
 
 Sp. Gr. 
 
 Gay-Lussac's Alcoholm. 
 
 Oleine or Tallow Oil 
 
 0 9003 
 
 66 
 
 Oil of Turnip Seed - 
 
 0 9128 
 
 60| 
 
 Rape Oil - 
 
 0-9136 
 
 60^ 
 
 Olive Oil - 
 
 0-9176 
 
 58 § 
 
 Purified Whale Oil - 
 
 0-9231 
 
 551 
 
 Oil of Poppies - 
 
 0-9243 
 
 55\ 
 
 Oil of Camelina - 
 
 0-9252 
 
 54| 
 
 Linseed Oil - 
 
 0-9347 
 
 50 
 
 Castor Oil - 
 
 0-9611 
 
 33^ 
 
 108 
 
PAPER. 
 
 195 
 
 M. Laurot, a Parisian chemist, finds that colza oil (analogous to rapeseed oil) may 
 be tested for sophistication with cheaper vegetable oils by the increase of density 
 which it therefrom acquires, and which becomes very evident when the several oils 
 are heated to the same pitch. The instrument, which he calls an oleometer, is merely 
 a hydrometer, with a very slender stem. He plunges it into a tin cylinder filled with 
 the oil, and sets this cylinder in another containing boiling water. His oleometer is 
 so graduated as to sink to zero in pure colza oil so heated ; and he finds that it stops 
 at '210° in linseed oil, at 124° in poppy-seed oil, at 83° in fish oil, and at 136° in hemp- 
 seed oil — all of the same temperature. By the increase of density, therefore, or the 
 ascent of the stem of the hydrometer in any kind of colza oil, he can infer its degree 
 of adulteration. 
 
 The presence of a fish oil in a vegetable oil is readily ascertained by agitation with a 
 little chlorine gas, which blackens the fish oil, but has little or no effect upon the 
 vegetable oil. 
 
 J find that lard oil, and also hogs'-lard, are not at all darkened by chlorine. 
 
 A specific gravity, bottle or globe, having a capillary tube-stopper, would make an 
 excellent oleometer, on the above principle. The vessel should be filled with the oil, 
 and exposed to the heat of boiling water, or steam at 212°, till it acquires that tem- 
 perature, and then weighed. The vessel with the pure colza oil will weigh several 
 grains less than with the other oils similarly treated. Such an instrument would serve 
 to detect the smallest adulterations of sperm oil. Its specific gravity at # 60 o when 
 pure is only 0 875 ; that of southern whale oil is 0*922, or 0'925 ; and hence their 
 mixture will give' a specific gravity intermediate, according to the proportion in the 
 mixture. Thus I have been enabled to detect sperm oil in pretended lard oil, in my 
 examination of oils for the customs. 
 
 OPIUM ; imported for consumption in 1839, 41,632 lbs. ; in 1840, 46,736; duty, 
 Is. per lb. 
 
 P. 
 
 PAPER. The construction of wire web cylinders for paper-making machines, 
 and the combination of two such cylinders - in one machine, by the use of which two 
 distinct thicknesses of paper pulp are obtained, and applied face-wise, to form 
 one thick sheet, were made the subject of a patent, under the name of John Donkin. 
 Two cylinders are so placed in a vat that their circumferences are nearly in contact, 
 and by being turned in opposite directions, they bring two sheets of paper pulp into 
 contact, and incorporate them into one, by what is technically termed couching. 
 
 An extensive patent for improvements in the manufacture of paper was granted to 
 Charles Edward Amos in 1840. These consist, first, in gradually lowering the roll of 
 the engine in which the rags are prepared and converted into pulp; secondly, in a mode 
 of regulating the supply of pulp to the paper-making machine, in order to produce papers 
 of any required thickness ; thirdly, in an improved sifter or strainer through which the 
 pulp is passed for clearing it of knobs and lumps ; fourthly, in certain modifications of 
 the parts of the machine in which the pulp is deposited and moulded into continuous 
 lengths of paper; fifthly, in an improved method of heating the cylinders of the drying 
 apparatus ; and, sixthly, in improvements of the machinery for cutting the paper into 
 sheets of any required dimensions. The details of these ingenious contrivances, 
 illustrated with engravings, are given in Newton's Juvrnal, xx., p. 15-3. C. S. 
 
 Henry Crossley purposes to manufacture paper from waste tan, and spent hops — 
 with what success I have not heard. Joseph Hughes gives a higher finish to the 
 long web of paper by friction between two cylinders, the one of which moves much 
 quicker than the other, both being covered with felt or not, at pleasure. 
 
 Mr. John Dickinson, the eminent paper manufacturer, obtained a patent in 1840 
 for a new mode of sizing paper continuously, in an air-tight vessel (partly exhausted 
 of air), by unwinding a scroll of dried paper from a reel, and conducting it through 
 heated size ; then, after pressing out the superfluous size, winding the paper on to 
 another reel. 
 
 A longitudinal section of the apparatus employed for this purpose is represented 
 fig. 109.; where a is the air-tight vessel ; b, the reel upon which the paper to be sized 
 is wound ; whence it proceeds beneath the guide-roller c, and through the warm size 
 to another guide-roller d. It thence ascends between the press-rolls, e,f (by whose re- 
 volution the paper is drawn from the reel b), and is wound upon the reel g. A float 
 h is suspended from the cross-bar i, of the vessel a, for the purpose of diminishing the 
 surface of size exposed to evaporation ; and beneath the bottom of the vessel is an 
 
 C c 2 
 
196 
 
 PAPER. 
 
 enclosed space j, into which steam or hot water is introduced for maintaining the tem- 
 perature of the size. — Sfewton's Journal, xxiii. 20. 
 
 Messrs. Charles Cowan and Adam Ramage, paper makers, patented, in 1840, im- 
 proved rag machinery ; in which a cylindrical sieve or strainer of wire cloth, of a 
 peculiar construction, is substituted for the ordinary strainers, by which the dirty water 
 is separated from the pulp. They do not claim the cylindric form of sieve, but " the 
 adding or applying, and combining within the interior of such drum, scoops, or 
 buckets, for the purpose of elevating the water, which has entered into it through its 
 wire circumference, so that the water when elevated may be able to run by its own 
 gravity out of the hollow around the central axis of the drum into any suitable shoot 
 or trough, and escape at a level above the surface of the water and rags or material 
 contained in the paper-machine." 
 
 Thomas Barrett claims, in his patent of 1841, " a mode of drying paper by applying 
 streams of air to its two surfaces, as it passes over the steam cylinders, whether in the 
 state of engine size or water leaf, or after sizing ; as also, the application of currents of 
 air to the surfaces of paper, after sizing, in order to cool the size ; as the paper is pass- 
 ing to the drying cylinders." 
 
 The improvements in paper making, for which T. W. Wrigley, of Bridge Hall 
 Mills, Bury, obtained a patent in 1842, relate to the rag engine, Jigs. 110, 111, 112, 
 
PAPER. 
 
 197 
 
 113. Fig. 110. is a side elevation; fig. 111. a transverse section, taken lengthwise 
 through nearly its middle ; fig. 112., a plan view of the apparatus detached upon a 
 
 larger scale ; and fig. 113. is an elevation. The vessel in which the rags are placed is 
 shown at a a, and in about the centre of this vessel the beating or triturating roll, b b, 
 is placed: it is surrounded with the blades or roll bars, c c, fig. 111. The roll is 
 mounted upon a shaft, d d, one end of which is placed in a pedestal or bearing on the 
 further side of the chamber a, and the other in a bearing upon the arm or lever e e*, 
 fig. 110., which is supported by its fulcrum, at the end e*, in one of the standards, f f, 
 and at the other end by a pin fixed in the connecting rod, g g. At the upper end of 
 this connecting rod there is a cross-piece, or head h, having turned pivots at each end 
 upon which are placed small rollers, i i, resting upon a horizontal cam, k k, which is 
 made to revolve. This cam, k k, by means of its gearing, causes the roll b first of all 
 to wash the rags a short time, then to be lowered at whatever rate is desired for break- 
 ing the fibres; to be maintained at the lowest point for the required number of revolu- 
 tions for beating ; and to be raised and retained, as required, for the final purpose of 
 clearing the pulp. The upper or working edge of this cam is to be shaped exactly 
 according to the action required by the engine roll ; as, for instance, suppose the 
 previous operation of washing to be completed, and the time required for the operation 
 of the rag machine to be three hours, one of which is required for lowering the roll, 
 that, or the first division of the working surface of the cam, k k, must be so sloped or 
 inclined, that, according to the speed at which it is driven, the rollers upon the cross- 
 head shall be exactly that portion of the time descending the incline upon the cam, 
 and consequently lowering the roll upon the plates n, fig. 111.; and if the second hour 
 shall be required for the roll to beat up the rags, the roll revolving all the time in 
 contact with the plates, the second division of the cam, k k, must be so shaped (that 
 is, made level), that the roll shall be allowed to remain, during that period, at its lowest 
 point ; and if the third portion of the time, or an hour, be required for raising the roll 
 again, either gradually or interruptedly, then the third division of the cam, k, must be 
 suitably shaped or inclined, so as to cause the cross-head to lift the roll during such 
 interval or space of time ; the particular shape of the inclined portions of the cam 
 depending on the manner in which the manufacturer may wish the roll to approach to 
 or recede from the bottom plates, during its descent and ascent respectively. 
 
 Its mode of connexion and operation in the rag engine is as follows : supposing that 
 the rags intended to be beaten up are placed in the vessel a, fig. 111., and motion is 
 communicated, from a steam-engine or other power, to the farther end of the shaft d, 
 the roll, b, will thus be caused to revolve, and the rags washed, broken, and beaten up, 
 as they proceed from the front weir m, over the bottom plates n, and again round by 
 the back weir o. There is a small pulley p, upon the near end of the shaft d, round 
 which a band q passes, and also round another pulley r, upon the cross shaft s ; upon 
 this shaft is a worm t, gearing into a worm-wheel u, fixed upon another shaft v, below ; 
 upon the reverse end of which is a pinion w, gearing into a spur-wheel x\ upon the end 
 of a shaft y ; and upon the centre of this shaft y, there is another worm z, gearing 
 into a horizontal worm-wheel 1, upon which the cam, k k, is fixed. Thus it will be 
 seen, that the requisite slow motion is communicated to the cam, which may be made 
 to perform half a revolution in three hours ; or it will be evident, that half a revolution 
 of the cam, k k, may be performed in any other time, according to the calculation of the 
 gearing employed. The shaft may also be driven by hand, so as to give the required 
 motion to the cam. Supposing, now, at the beginning of the operation, the cross head 
 bearing the lever and roll, to be at the highest point upon the cam, k k, as its revolu- 
 tion commences, the roll will revolve for a short time on the level surface of the cam, 
 and will then be lowered until the cam, k k, has arrived at that point which governs the 
 time that the roll remains at the lowest point, for the purpose of beating the rags into 
 pulp, and as the cam, k k, continues to revolve, and thus brings the opposite slope upon 
 
198 
 
 PEARLS, ARTIFICIAL. 
 
 the third portion of its .working surface into action upon the cross head, the roll will be 
 raised, in order to clear the pulp from knots and other imperfections, and thus complete 
 the operation of the engine. In order to raise the cross head and roll to the height 
 from which it descended without loss of time, or to lift the cross-head entirely from off 
 the cam when requisite ; a lever 2, or other suitable contrivance may be attached to the 
 apparatus, also a shaft may be passed across the rag-engine, and both ends of the roll 
 may be raised instead of one only, as above described. 
 
 The patentee does not claim as his invention the lowering and raising the roll of 
 the rag engine, nor the lowering of it by mechanism, as this was effected in Mr. Amos's 
 patent of 1840 ; but he claims the above peculiar apparatus for this purpose. — New- 
 ton's Journal, xxiii. 254. C. S. 
 
 PAPER — Cross produce of revenue from. In 1831, 7 23,2487. ; 1836, 812,7827. ; 
 1837, 555,9437. ; 1840, 626,6637. 
 
 PAPER CLOTH. The preparation of this fabric is thus described in the speci- 
 fication of Mr. Henry Chapman's patent of January 1843. A suitable quantity of 
 canvass, gauze, muslin, calico, linen, &c, is wound upon a roller, which is introduced 
 between the third press felt of a Fourdrinier paper machine ; and between the above 
 roller and the endless felt a trough is introduced, containing a solution of gum, glue, 
 &c, with a roller partially immersed in it. Pulp being now allowed to flow upon the 
 endless wire wheel of the machine, paper is made in the ordinary way ; and when the 
 endless sheet of paper has been led through the machine, the end of the cloth is 
 brought over the upper part of the roller in the trough, and moved onwards in the 
 direction the paper is proceeding. The motion of the cloth causes the roller to revolve, 
 and the adhesive material carried upon its surface is imparted to the cloth, which is 
 then laid upon the paper, as it passes over the roller immediately preceding the third 
 or last press-roller. By passing between these rollers, the cloth and paper are firmly 
 united, and being dried by the steam cylinders, form the compound fabric. If required, 
 a paper surface may be applied to the other side of the cloth, by repeating the opera- 
 tion. If the cloth be dressed with strong starch, the bath of adhesive solution may be 
 dispensed with. The following prescription is given for making that solution : — 
 
 Dissolve in 15 parts of water, 4 of soda, and combine with this solution, by means 
 of heat, 9 parts of yellow rosin ; boil for an hour, adding a little linseed oil to prevent 
 frothing, and add 1 part of glue to the mixture ; after which dilute the whole with one 
 and a half times its weight of water, and strain through flannel. Thirty parts of this 
 composition are to be mixed with one part of flour-paste, and six parts of paper-pulp, 
 which mixture is to be used warm. 
 
 PEARLS, ARTIFICIAL, and BEADS. The material out of which these are 
 formed are small glass tubes like those with which thermometers are made. The tubes 
 for the bright red pearls consist of two layers of glass, a white opaque one internally, 
 and a red one externally ; drawn from a ball of white enamel, coated in the Bohemian 
 method with ruby-coloured glass, either by dipping the white ball into a pot of red 
 glass, and thus coating it, or by introducing the ball of the former into a cylinder of 
 the latter glass, and then cementing them so soundly together as to prevent their 
 separation in the subsequent pearl processes. These tubes are drawn in a gallery of 
 the glasshouse to 100 paces in length, and cut into pieces about a foot long. These 
 are afterwards subdivided into cylindric portions of equal length and diameter, pre- 
 paratory to giving them the spheroidal form. From 60 to 80 together are laid 
 horizontally in a row upon a sharp edge, and then cut quickly and dexterously at once 
 by drawing a knife over them. The broken fragments are separated from the regular 
 pieces by a sieve These cylinder portions are rounded into the pearl shape by softening 
 them by a suitable heat, and stirring them all the time. To prevent them from stick- 
 ing together, a mixture of gypsum and plumbago, or of ground clay and charcoal, is 
 thrown in among them. 
 
 Figs. 114, 115. represent a new apparatus for rounding the beads; fig. 114. is a 
 front view of the whole; fig. 115. is a section through the middle of the former figure, 
 in the course of its operation. The brick furnace, strengthened with iron bands, 2, 3. 
 5. 7, 8. has in its interior (see fig. 115.) a nearly egg-shaped space b, provide^ with 
 the following openings : beneath is the fire-hearth, c, with a round mouth, and opposite 
 are the smoke flue and chimney, n ; in the slanting front of the furnace is a large open- 
 ing, e, fig. 114. Beneath are two smaller oblong rectangular orifices, f, g, which 
 extend somewhat obliquely into the laboratory, b. h serves for introducing the wood 
 into the fireplace. All these four openings are, as shown in fig. 114., secured from 
 injury by iron mouth-pieces. The w.>od is burned upon an iron or clay bottom piece, r. 
 A semi-circular cover, n, closes during the operation the large opening, e, which at 
 other times remains open. By means of a hook, m, and a chain, which rests upon a 
 hollow arch, /*, the cover, n, is connected with the front end of the long iron lever, r, h'. 
 A prop supports at once the turning axis of this lever and the catch, 6, c ,• the weight, 
 
PEARLS, ARTIFICIAL. 
 
 199 
 
 q, draws the arm, r, down, and thereby holds up k ; e therefore remains open. By 
 rods on the back wall, t, t, the hook, i, in which r' rests, proceeds from /. When r' 
 
 is raised r sinks. The catch, c b, enters with its front tooth into a slanting notch upon 
 the upper edge of r, spontaneously by the action of the spring, e; whereby the open- 
 ing, e, is shut. The small door, n, rises again with the front arm of the lever 
 by the operation of the weight q of itself, as soon as the catch is released by pressure 
 upon c. 
 
 The most important part of the whole apparatus is the drum, k, for the reception 
 and rounding of the bits of glass. It may be made of strong copper, or of hammered 
 
 or cast iron, quite open above, and 
 pierced at the bottom with a square 
 hole, into which the lower end of 
 the long rod, t, is exactly fitted, and 
 secured in its place by a screwed 
 collector nut. The blunt point, x, 
 {fig. 114.) rests during the work- 
 ing in a conical iron step of the 
 laboratory, fig. 1 15. On the mouth 
 of the drum, k, a strong iron ring 
 is fixed, having a bar across its dia- 
 meter, with a square hole in its 
 middle point, fitted and secured by 
 a pin to the rod t, and turned by 
 its rotation. The vessel k, and its 
 axle, t, are laid in a slanting direc- 
 tion ; the axle rests in the upper 
 ring, 2, at the lower end of the 
 rod, I, of which the other end is 
 hung to the hook, n, upon the 
 mantel beam, n. On the upper end 
 of t, the handle, s, is fixed for turn- 
 ing round continuously the vessel, 
 k, while the fire is burning in the 
 furnace, the fuel being put not only 
 in its bottom chamber, but also into 
 the holes, f, g (fig. 114.). The 
 fire-wood is made very dry before 
 being used, by piling it in logs upon 
 the iron bars, 9, 10, 11. under the mantelpiece, as shown mfigs. 114, 115. 
 
200 
 
 PEPPER. 
 
 After the operation is finished, and the cover, n, is removed, the drum is emptied of 
 its contents, as follows. Upon the axle, t, there is towards k a projection at Along- 
 side the furnace {fig. 114.) there is a crane, m, that turns upon the step, s, s, on the 
 ground. The upper pivot turns in a hole of the mantel-beam, n. Upon the perpen- 
 dicular arm, w, of the crane there is a hook, y, and a ring, q, in which the iron rod, p, 
 is movable in all directions. When the drum is to be removed from the furnace, the 
 crane, with its arm, w, must be turned inwards, the under hook of the rod, p, is to be 
 hung in the projecting piece, u, and the rod, I, is lifted entirely out. After this, by 
 means of the crane, the drum can be drawn with its rod, t, out of the furnace ; and 
 through the mobility of the crane, and its parts, p, q, any desired position can be given 
 to the drum. Fig. 114. shows how the workman can with his hand applied to s' de- 
 press the axle, t, and thereby raise the drum, k, so high that it will empty itself into 
 the pot, l, placed beneath. When left to itself, the drum on the contrary hangs nearly 
 upright upon the crane by means of the rod, p, and may therefore be easily filled 
 again in this position. The manner of bringing it into the proper position in the 
 furnace by means of the crane and the rod, /, is obvious from fig. 1 1 5. 
 
 The now well-rounded beads are separated from the pulverulent substance with 
 which they were mixed by careful agitation in sieves ; and they are polished finally 
 and cleaned by agitation in canvas bags. 
 
 PENS, STEEL. When these have been punched out of the softened sheet of 
 steel by the appropriate tool, fashioned into the desired form, and hardened by ignition 
 in an oven and sudden quenching in cold water, they are best tempered by being 
 heated to the requisite spring elasticity in an oil bath. The heat of this bath is 
 usually judged of by the appearance to the eye ; but this point should be correctly 
 determined by a thermometer, according to the scale (see Steel in the Dictionary); 
 and then the pens would acquire a definite degree of flexibility or stiffness, adapted to the 
 wants and wishes of the consumers. They are at present tempered too often at random. 
 
 PEPPER. The unripe grains or corns are known under the name of black 
 pepper; the ripe ones, deprived of their epidermis, constitute white pepper. The 
 latter are very generally bleached by steeping for a little while in a solution of chloride 
 of lime, subsequent washing and drying ; a process which improves their aspect, but 
 not their flavour. I was recently led to examine the nature of this substance some- 
 what minutely, from being called professionally to investigate a sample of ground 
 white pepper belonging to an eminent spice-house in the city of London, which pepper 
 had been seized by the Excise on the charge of its being adulterated, or mixed with 
 some foreign matter, contrary to law. I made a comparative analysis of that pepper 
 and of genuine white pepper-corns, and found both to afford like results: viz. in 100 
 grains, a trace of volatile oil, in which the aroma chiefly resides ; about 81 grains of a 
 pungent resin, containing a small fraction of a grain of piperine ; about 60 grains of 
 starch, with a little gum, and nearly 30 grains of matter insoluble in hot and cold 
 water, which may be reckoned lignine. The two chemists in the service of the Excise 
 made oath before the court of judicature, that the said pepper contained a notable 
 proportion of sago, even to the amount of fully 10 per cent ; grounding their judgment 
 upon the appearance of certain rounded particles in the pepper, and of the deep blue 
 colour which these assumed when moistened with iodine water. No allegation could 
 be more frivolous. Bruised corns of genuine white pepper, certainly acquire as deep a 
 tint with iodine as any species of starch whatever. But the characters of sago, 
 optical and chemical, are so peculiar, as to render the above surmise no less preposterous, 
 than the prosecution of respectable merchants, forlsuch a cause, was unjustifiable. A 
 particle of sago appears in the microscope, by reflected light, to be a spherule of snow, 
 studded round with brilliants ; whereas the rounded particles of the seized pepper seem 
 to be amorphous bits of grey clay. Had the pepper been adulterated with such a 
 quantity of sago, or anything else, as was alleged, it could not have afforded me, by 
 digestion in alcohol, as much of the spicy essence as the bruised genuine pepper- 
 corns did. 
 
 Moreover, sago steeped for a short time in cold water, swells and softens into a 
 pulpy consistence, whereas the particles of the seized pepper, rounded by attrition in 
 the mill, retain, in like circumstances, their hardness and dimensions. Sago, being 
 pearled by heating and stirring the fine starch of the sago palm in a damp state, upon 
 iron or other plates, acquires its peculiar somewhat loose aggregation and brilliant 
 surface ; while, in pepper, the starchy constituent is compactly condensed, and bound 
 up with its ligneous matter. 
 
 The Excise laws are sufficiently odious and oppressive in themselves without being 
 aggravated by the servile sophistry of pseudo-science. 
 
 Four pounds of black pepper yield only about one ounce of piperine, or one 
 636th part. It is an insipid crystalline substance, insoluble in water, but very soluble 
 in boiling alcohol, and is extracted at first along with the resin, which may be separated 
 from it afterwards, by potash. 
 
PHOTOGRAPHY. 
 
 201 
 
 PERFUMERY, INDIAN. The natives place on the ground a layer of the 
 scented flowers, about 4 inches thick and 2 feet square ; cover them with a layer 2 inches 
 thick of Tel or Sesamum seed wetted ; then lay on another 4 inch bed of flowers, and 
 coyer this pile with a sheet, which is pressed down by weights round the edges. After 
 remaining in this state for 18 hours, the flowers are removed and replaced by a similar 
 fresh layer, and treated as before ; a process which is repeated a third time if a very rich 
 perfumed oil be required. The sesamum seeds thus embued with the essential oil of 
 the plant, whether jasmine, Bela, or Chumbul, are placed in their swollen state in a mill, 
 and subjected to strong pressure, whereby they give out their bland oil strongly im- 
 pregnated with the aroma of the particular flower employed. The oil is kept in pre- 
 pared skins called dubbers, and is largely used by the Indian women. The attar of 
 roses is obtained by distillation at a colder period of the year. 
 
 PHOTOGRAPHY is the art of making pictorial impressions of objects by the 
 action of light upon paper, &c, prepared with certain substances, and exposed to the sun 
 or in the focus of a camera obscura to the image of the object to be represented; which 
 impressions are then fixed by other chemical reagents. Photographic paper may be 
 made by dipping Whatman's glazed post paper into brine containing 90 grains of 
 common salt dissolved in an ounce of water, wiping it with a towel, brushing over one 
 side of it with a broad camel-hair brush, a solution of nitrate of silver, containing 
 50 grains to the ounce of distilled water, and drying it in the dark. The paper may 
 be rendered more sensitive by repeating the above operation ; drying it between each 
 step. It affords perfect images of leaves and petals laid upon it, and exposed simply 
 to the sun-beams. A solution of 100 grains of bromide of potassium in an ounce of 
 distilled water answers still better than brine. The paper, when dry, is to be brushed 
 over on one side with a solution containing 100 grains of nitrate of silver to an ounce 
 of water ; the paper being brushed, and dried in the dark. If the application of the 
 nitrate of silver be repeated, it will render the paper more sensitive. The silvered side 
 should be marked. This paper laid flat. under painted glass, lace, leaves, feathers, 
 ferns, &c, and exposed to the light of day, takes the impression of the objects. It is 
 to be then washed with lukewarm water, and finally dipped in a solution containing 
 one ounce of hyposulphite of soda, in about a pint of distilled water. The design of- 
 the object is necessarily reversed ; the light parts forming the dark shades of the 
 photogenic impression, and the dark parts the lighter ones. But a direct picture may 
 be obtained by applying that paper, rendered transparent with white wax (see Calo- 
 type), upon a sheet of white photogenic paper, and exposing it to the sunbeams, or 
 bright day-light. 
 
 A modification of Photography, called Chrysotype by its inventor, Sir John 
 Herschel, consists in washing the paper in a solution of ammonia-citrate of iron, drying 
 it, and brushing it over with a solution of tevYO-sesquicydimrc of potassium. This paper, 
 when dried in a perfectly dark room, is ready for use, the image being finally brought 
 out by a neutral solution of silver. 
 
 Another modification by Sir John, called Cyanotype, is as follows : — Brush the 
 paper with the solution of the ammonia-citrate of iron, so strong as to resemble sherry 
 wine in colour ; expose the paper in the usual way, and pass over it very sparingly 
 and evenly a wash made by dissolving common ferro-cyanide of potassium. As soon as 
 this liquid is applied, the negative picture vanishes, and is replaced by the positive one, 
 of a violet blue colour, on a greenish yellow ground, which at a certain time possesses 
 a high degree of sharpness, and singular beauty of tint. 
 
 The improved process of photography recently contrived by Mr. Robert Hunt is 
 performed by washing over good letter paper with the following liquid: — 
 
 A saturated solution of succinic acid 2 drams 
 
 Mucilage of gum arabic - \ do. 
 
 Water - - - - - - li do. 
 
 When the paper is dry, it is washed over once with a solution containing I dram of 
 nitrate of silver in 1 ounce of distilled water. The paper is allowed to dry in the 
 dark, and it is Wt for use. It can be preserved in a portfolio, and employed at any 
 time in the camera obscura, exposing it to the light from two to eight minutes according 
 to its vivacity. When the paper is taken out of the camera, no trace of a picture can 
 be seen. To produce this effect mix 1 dram of a saturated solution of sulphate of 
 iron, with 2 or 3 drams of mucilage of gum arabic, and brush over the paper evenly 
 with this mixture. In a few seconds the latent images are seen to develope themselves, 
 producing a negative photographic picture. The excess of the iron solution is to be 
 washed off with a sponge whenever the best effect appears. The drawing is then to be 
 soaked a short time in water, and is fixed by washing over with ammonia, or preferably 
 with hyposulphite of soda ; taking care to wash out the excess of salt. From the 
 pictures thus produced, any number of others, corrected in light and shadow, may be 
 
 D d 
 
202 
 
 PITCOAL, ANALYSIS OF. 
 
 produced by using like succinated papers, in the common way of transfer in sunshine. 
 — Athenaeum. 
 
 PICKLES are various kinds of vegetables and fruits preserved in vinegar. The 
 substances are first well cleaned with water, then steeped for some time in brine, and 
 afterwards transferred to bottles, which are filled up with good vinegar. Certain 
 fruits, like walnuts, require to be pickled with scalding hot vinegar ; others, as red cab- 
 bage, with cold vinegar ; but onions, to preserve their whiteness, with distilled vinegar. 
 Wood vinegar is never used by the principal pickle manufacturers, but the best malt 
 or white wine vinegar, No. 22 or 24. Kitchener says, that by parboiling the pickles in 
 brine, they will be ready in half the time of what they require when done cold. Cab- 
 bage, however, cauliflowers, and such articles would thereby become flabby, and lose 
 that crispness which many people relish. When removed from the brine, they should 
 be cooled, drained, and even dried before being put into the vinegar. To assist the 
 preservation of pickles, a portion of salt is often added, and likewise to give flavour, 
 various spices, such as long pepper, black pepper, white pepper, allspice, ginger, cloves, 
 mace, garlic, mustard, horse-radish, shallots, capsicum. When the spices are bruised 
 they are most efficacious, but they are apt to render the pickle turbid and discoloured. 
 The flavouring ingredients of Indian pickle are Curry powder mixed with a large pro- 
 portion of mustard and garlic. Green peaches are said to make the best imitation of 
 the Indian Mango. 
 
 I have examined the apparatus in the .great fish-sauce, pickle, and preserved fruit 
 establishment of Messrs. Crosse and Blackwell, Soho Square, and found it arranged on 
 the principles most conducive to economy, cleanliness, and salubrity ; no material em- 
 ployed there is ever allowed to come into contact with copper. A powerful steam boiler 
 is placed in one corner of the ground floor of the factory, from which a steam pipe 
 issues, and is laid horizontally along the wall about 4 feet above the floor. Under 
 this pipe a range of casks is placed, into the side of each of which a branch steam- 
 pipe, furnished with a stopcock, is inserted, while the mouth of the cask is exactly 
 closed with a pan of salt-glazed earthenware, capable of resisting the action of every 
 acid, and incapable of communicating any taint to its contents. These casks form, by 
 their non-conducting quality as to heat, the best kind of steam-jackets. In these pans 
 the vinegars with their compounds are heated, and the fish and other sauces are pre- 
 pared. The waste steam at the farthest extremity of the pipe is conducted into a re- 
 sorvoir of clean water, so as to furnish a constant supply of hot water for washing 
 bottles and utensils. 
 
 The confectionary and ham- smoking compartments are placed in a separate fire-proof 
 chamber on the same floor. 
 
 The floor above is occupied along the sides with a range of large rectangular cast- 
 iron cisterns, furnished with a series of steam-pipes, laid gridiron-wise along their bot- 
 toms, which pipes are covered with a perforated wooden shelf. These cisterns being 
 filled up to a certain height above the shelf with water, the bottles full of green goose- 
 berries, apricots, cherries, &c, to be preserved, are set upon the shelf, and the steam 
 being then admitted into the gridiron pipes, the superjacent water gets gradually heated 
 to the boiling point ; the air in the bottles round the fruit is thus partly expelled by 
 expansion, and partly disoxygenated by absorption of the green vegetable matter. 
 In this state the bottles are tightly corked, and being subsequently sealed preserve the 
 fruit fresh for a very long period. 
 
 The sauces, pastes, and potted meats prepared in the above described apparatus, can 
 seldom be rivalled and probably not surpassed in the kitchens of the most fastidious 
 gastronomes. 
 
 PITCOAL, ANALYSIS OF. The greater part of the analyses of coals hitherto 
 published have been confined to the proportions of carbon, hydrogen, and oxygen, to 
 the neglect of the sulphur, which exists in many coals to a degree unwholesome for 
 their domestic use, pernicious for the smelting of iron, and detrimental to the 
 production of gas ; since the sulphuretted hydrogen produced requires so much 
 washing and purification as at the same time to impoverish the light, by condensing 
 much of the olefiant gas, its most luminiferous constituent. In the numerous reports 
 upon the composition of coals which I have been professionally called upon to make, I 
 have always sought to determine the proportion of sulphur, which may be done readily 
 to one part in a thousand ; as also, that of combustible gaseous matter, of coke, and 
 of incombustible ashes. 
 
 The following coals have been found to be of excellent quality, as containing very 
 little sulphur, seldom much above 1 percent., and little incombustible matter, — hence 
 well adapted as fuel, whether for steam navigation, for iron smelting, for household 
 consumption, or for gas, according to their relative proportions of carbon and hy- 
 drogen ; a relative excess of carbon constituting a coal best adapted for furnaces of 
 
POTTER'S OVEN. 
 
 203 
 
 various kinds, while a relative excess of hydrogen forms the best coal for the common 
 grates and gas works. 
 
 1. Mr. PowelVs Duffry, or Steam Coal. — Specific gravity, 1*32; ashes, per cent, 2-6; 
 gaseous products in a luted crucible, 14; brilliant coke, 86; not more than 1 per 
 cent of sulphur ; while many of the Newcastle coals contain from 4 to 6, and others 
 which I have examined from 8 to 10 of the same noxious constituent ; and which is a 
 less powerful calorific constituent than hydrogen and carbon. 
 
 2. The Blackley Hurst Coal of Lancashire. — Specific gravity, 1 "26 ; ashes, per 
 cent., 1 -2 ; combustible gases, 41 '5 ; coke, 58 5 ; sulphur, 1. Another specimen had a 
 specific gravity of 1*244 ; 2 per cent, of ashes; 38*5 of combustible gases ; 1 of sulphur. 
 This is a very good coal for gas, and for domestic use. 
 
 3. The Farley Rock Vein Coal, near Pontypool ; shipped by Mr. John Vipond. — . 
 Specific gravity, 1 "296 ; ashes (whitish) 5 per cent. ; 32 of combustible gases ; 68 
 of coke. Sulphur from 2 to 3 per cent. A good household coal. 
 
 4. The Llangennech Coal has a well-established reputation for the production of 
 steam, and is much employed by the British government for steam navigation, as well 
 as at Meux's, and others of the great breweries in London. It affords a very intense heat, 
 with little or no smoke ; and sufficiently diffusive, for extending along the flues of the 
 boilers ; whereas the Anthracite coal, containing very little hydrogen, yields, in common 
 circumstances, a heat too much concentrated under the bottom of the boilers, and 
 acting too little upon their sides. Specific gravity, 1 -337 ; intermediate between that 
 of the Newcastle and the Anthracite. Ashes per cent, from 3 to 3*5; combustible 
 gases, 17; coke, 83; sulphur, only one half per cent. It is therefore a pure and very 
 powerful fuel. 
 
 I have examined many coals with my calorimeter ; of which some account is given 
 under Fuel. 
 
 PLATING. See Electrotype. 
 
 PLATINUM MOHR. This interesting preparation, which so rapidly oxidizes 
 alcohol into acetic acid, &c, by what has been called in chemistry the catalytic or 
 contact action, is most easily prepared by the following process of M. Boettger : — The 
 insoluble powder of potash-chlorure or ammonia-chlorure of platinum, is to be mois- 
 tened with sulphuric acid (oil of vitriol), and a bit of zinc is to be laid in the mixture. 
 The platinum becomes reduced into a black powder, which is to be washed first with 
 muriatic acid, and then with water. The fineness of this powder depends upon that 
 of the saline powders employed to make it ; so that if these be previously finely 
 ground, the platinum-mohr will be also very fine, and proportionally powerful as a 
 chemical agent. 
 
 POTTER'S OVEN. A patent' was obtained in August, 1842, by Mr. W. Ridg- 
 way, for the following construction of oven, in which the flames from the fire-places are 
 conveyed by parallel flues, both horizontal and vertical, so as to reverberate the whole 
 of the flame and heat u.pon the goods after its ascension from the flues. His oven is 
 built square instead of round, a fire-proof partition wall being built across the middle 
 of it, dividing it into two chambers, which are covered in by two parallel arches. The 
 fire-places are built in the two sides of the oven opposite to the partition wall ; from 
 which fire-places narrow flues rise in the inner face of the wall, and distribute the 
 flame in a sheet equally over the whole of its surface. The other portion of the heat 
 is conveyed by many parallel or diverging horizontal flues, under and across the floor 
 or hearth of the oven, to the middle or partition wall ; over the surface of which the 
 flame which ascends from the numerous flues in immediate contact with the wall is 
 equally distributed. This sheet of ascending flame strikes the shoulder of the arch, 
 and is reverberated from the seggars beneath, till it meets the flame reverberated from 
 the opposite side of the arch, and both escape at the top of the oven. The same con- 
 struction is also applied to the opposite chamber. In figs. 116, 117, «, represents the 
 
 D d 2 
 
204 
 
 PRUSSIATE OF POTASH. 
 
 squart walls or body of the oven ; b, the partition wall ; c, the fire-places or furnaces 
 with their iron boilers; d, the mouths of the furnaces for introducing the' fuel; f, the 
 ash-pits; g, the horizontal flues under the hearth of the oven; h, the vertical flues; 
 i, the vents in the top of the arches ; and k, the entrances to the chambers of the 
 ovens. 
 
 PRUSSIAN BLUE. The following process deserves peculiar notice, as the first 
 in which this interesting compound has been made to any extent, independently of 
 animal matter. Mr. Lewis Thompson, of the Old Barge House, Lambeth, received a 
 well-merited medal from the Society of Arts for this invention. He justly observes, 
 that in the common way of manufacturing prussiate of potash, the quantity of nitrogen 
 furnished by a given weight of animal matter is not large, and seldom exceeds 8 per 
 cent. ; and of this small quantity, at least one half appears to be dissipated during the 
 ignition. It occurred to him that the atmosphere might be economically made to 
 supply the requisite nitrogen, if caused to act in favourable circumstances upon a mix- 
 ture of carbon and potash. He has found the following prescription to answer. Take 
 of pearlash and coke, each 2 parts ; iron turnings, 1 part ; grind them together into a 
 coarse powder ; place this in an open crucible, and expose the whole for half an hour to 
 a full red heat in an open fire, with occasional stirring of the mixture. During this 
 process, little jets of purple flame will be observed to rise from the surface of the mate- 
 rials. When these cease, the crucible must be removed and allowed to cool. The 
 mass is to be lixiviated; the lixivium, which is a solution of ferrocyanide of potassium, 
 with excess of potash, is to be treated in the usual way, and the black matter set aside 
 for a fresh operation, with a fresh dose of pearlash. Mr. Thompson states that one 
 pound of pearlash, containing 45 per cent, of alkali, yielded 1355 grains of pure Prus- 
 sian blue, or ferrocyanide of iron ; or about 3 ounces avoirdupois. 
 
 PRUSSIATE OF POTASH. Leuch's Polytechnic Zeitung, June 1837. Manufac- 
 ture of Kalium Eisen Cyanure, by Hofflmayr and Priikn'er. — The Potash must be free 
 from sulphate, for each atom of sulphur destroys an atom of the Eisencyankalium. A 
 very strong heat is advantageous. The addition of from 1 to 3 g of saltpetre is useful, 
 when the mass is too long of fusing. A reverberatory furnace (flammofen) is recom- 
 mended ; but the flame must not beat too much upon the materials for fear of oxy- 
 genating them. When the smoky red flame ceases, it is useful to throw in from time 
 to time small portions of uncarbonised animal matter, particularly where the flame first 
 beats upon the mass, whereby the resulting gases prevent oxidation by the air. The 
 animal matters should not be too much carbonised, but left somewhat brown coloured, 
 provided they be readily pulverised. Of uncarbonised animal matters, the proportions 
 may be 100 parts dried blood, to from 28 to 30 of potash (carbonate), and from 2 to 4 of 
 hammerschlag (smithy scales), or iron filings. 2d. 100 parts of horns or hoofs ; from 
 33 to 35 potash; 2 to 4 iron. 3d. 100 leather, 45 to 48 potash, and 2 to 4 iron. 
 From blood, 8 to 9 per cent, of the prussiate are obtained ; from horns, 9 to 10 ; and 
 from leather, 5 to 6. The potash should be mixed in coarse particles, like peas, with 
 the carbonised animal matter, which may be best done in a revolving pot, containing 
 cannon-balls. Of the animal coal and potash, equal parts may be taken, except with that 
 from leather, which requires a few parts more potash per cent. On the average, blood 
 and horn coal should afford, never less than 20 per cent, of prussiate, nor the leather 
 than 8 ; but by good treatment, they may be made to yield, the first 25, and the last 
 from 10 to 11. 
 
 A patent for a singular process and apparatus, for making this compound, was 
 obtained by a foreigner not named, by Mr. Berry, patent agent, in January, 1840. 
 The prescription is as follows : — 
 
 Reduce charcoal into bits of the size of a walnut, soak them with a solution of car- 
 bonate of potash in urine ; and then pour over them a solution of nitrate or acetate of 
 iron ; dry the whole by a moderate heat, and introduce them into the cast-iron tubes, 
 presently to be described. The following proportions of constituents have been found 
 to answer : — Ordinary 'potash, 30 parts; nitre, 10; acetate of iron, 15; charcoal or 
 coke, 45 to 55 ; dried blood, 50. The materials, mixed and dried, are put into retorts 
 similar to those for coal gas. The animal matter, however (the blood), is placed in 
 separate compartments of pipes connected with the above retorts. The pipes containing 
 the animal matter should be brought to a red heat before any fire is placed under 
 the retorts. 
 
 In fig. 118., a, b, c, n, is a horizontal section of a furnace constructed to receive four 
 elliptical iron pipes. The furnace is arched in the part a, c, b, in order to reverberate 
 the heat, and drive it back on the pipes w, w', w", w'". These pipes are placed on the 
 plane e, f, of the ellipsoid, a, a, represents the grating or bars of the furnace to be 
 heated with coal or coke ; i, i, is the pot or retort shown in figs. 119, 120, 121. 
 
 This pot or retort is placed in a separate compartment, as seen in fig. 119., which is a 
 
PRUSSIATE OF POTASH. 
 
 205 
 
 vertical section, taken through fig. 121., at the line g, m k, is a connecting tube, from 
 the retort and the elliptical pipes w. 
 
 In the section,^. 119., the shape of the tube k, will be better seen ; also its cocks u, 
 and likewise its connection with the pipes w. I, is a safety valve ; s, the cover of 
 the pot or retort ; i,, is the ash-pit ; and b, the door of the furnace ; x, is an open 
 space, roofed over, or a kind of shed, close to the furnace, and under it the pipes are 
 emptied. 
 
 The arrows indicate the direction of the current of heat. This current traverses 
 the intervals left between the pipes, and ascends behind them, passing through the 
 aperture j, in the brickwork, which is provided with a valve or damper, for closing it, 
 as required. The heat passes through this aperture, and strikes against the sides of 
 the pot when the valve is open. Another valve /, g, must also be open to expose the 
 pot or retort to the direct action of the fire. The smoke escapes by a lateral passage 
 into a chimney x. 
 
 It must be remarked, that there is a direct communication between the chimney and 
 that compartment of the furnace which contains the pipes, so that the heat, reflected 
 from the part v, strikes on the pot or retort only when the pipes w, w', w", w'", are 
 sufficiently heated. 
 
 In fig. 1 20. is shown an inclined plane M (also represented in fig. 119.) and the junc- 
 tion-tubes which connect the four pipes with their gas-burners z, z, and the cocks m, m'. 
 r, r, are covers, closing the pipes, and having holes formed in them ; these holes are 
 shut by the stoppers e. 
 
 Whether the pipes are placed in the vertical or horizontal position, it is always 
 proper to be able to change the direction of the current of gas; this is easily done by 
 closing, during one hour (if the operation is to last two hours,) the cocks u, m', and 
 opening those u', m ; then the gas passes through u', into the branch k, and entering 
 w'", passes through q, into w", through p, into w', and through o, and w, and finally 
 
206 
 
 PUDDLING OF IRON. 
 
 escapes by the burner z. During the following or other hour, the cocks u', m, must 
 be closed ; the cocks u, m', being opened, the current then goes from u, into k, w, w', 
 w", w'", and escapes by the burner z', where it may be ignited. 
 
 The changing of the direction of the current dispenses, to a certain degree, with the 
 labour required for stirring, with a spatula, the matters contained in the pipes ; never- 
 theless, it is necessary, from time to time, to pass an iron rod or poker amongst the 
 substances contained in the pipes. It is for this purpose that apertures are formed, so 
 as to be easily opened and closed. 
 
 The patentee remarks, that although this operation is only described with reference 
 to potash, for obtaining prussiate of potash, it is evident, that the same process is 
 applicable to soda; and when the above-mentioned ingredients are employed, soda 
 being subsituted for potash, the result will be prussiate of soda. — Newton's Journal, C. 
 S. xxi. 96. 
 
 PUDDLING OF IRON. This is the usual process employed in Great Britain 
 for converting cast iron into bar or malleable iron — a crude into a more or less pure 
 metal. The following plan of a puddling furnace has been deemed economical, espe- 
 cially with respect to fuel, as two furnaces are joined side by side together, and the 
 workmen operate at doors on the opposite sides. Fig. 122. represents this twin furnace 
 
 122 
 
 i r 
 
 i r 
 
 1 
 
 i r 
 
 j L 
 
 L7 
 
 in a side elevation ; Jig. 123. in section, according to the line E F, in fig. 124., which 
 exhibits a plan of the furnace. The various parts are so clearly shown in form and 
 construction as to require no explanation. The total length outside is 14| feet; width, 
 12^ feet ; from which the dimensions of the other parts may be measured. 
 
 Iron is puddled either from cast pigs, or from the plates of the refinery (finery) fur- 
 nace. In several iron- works a mixture of these two crude metals is employed. In the 
 refining process, the waste at the excellent establishment of Mr. Jessop, at Codner Park, 
 is from 2i to 2\ cwt. per ton; on which process the wages are Is. per ton; and the 
 coke, i ton, worth 6s. ; so that the total cost of refining per ton is 15s., when pig-iron 
 is worth 3/. 10s. 
 
 The puddling is accompanied with a loss of weight of 1± cwt. per ton; it costs in 
 wages, for puddling refinery plates, 6s. 6d., and for pigs, 8s. ; in which 18 cwt. of coal 
 are consumed ; value, 5s. per ton. 
 
 Shingling (condensing the bloom by the heavy hammer) costs, in wages, Is. 9d. 
 per ton; and rough-rolling, Is. 2d. Cutting and weighing these bars cost 9d. for 
 wages, including their delivery to the mill furnace, were they are re-heated and welded 
 
PUDDLING OF IRON. 
 
 207 
 
 together. The mill furnace heating costs Is. 6d. in wages, and consumes in fuel 12cwt. 
 of coals, at 5s. per ton. The rolling and straightening cost 5s. 6d. ; cropping the ends, 
 weighing, and stocking in the warehouse, Is. for wages. Wear and tear of power, 5s. 
 Labourers for clearing out the ashes, &c, Is. 6d. per ton. 
 
 In Wales 4 tons of pig-iron afford upon an average only 3 tons of bars. From the 
 above data a calculation may easily be made of the total expense of converting crude 
 into cast iron at the respective iron works. 
 
 A great economy in the conversion of the cast into wrought metal seems about to be 
 effected in our iron works, by the application of a current of voltaic electricity to the 
 crude iron in a state of fusion, whether on the hearth of the blast furnace, on the fused 
 pigs in the sand, or on the metal immediately on its being run from the finery fur- 
 nace ; the voltaic force of from 50 to 100 pairs of a powerful Smee's battery being 
 previously arranged to act upon the whole train of the metal. This process, for which 
 
208 
 
 RESINS. 
 
 Mr. Arthur Wall has recently obtained a patent, is founded upon the well-established 
 fact, that when a compound is subjected to an electrical current, its negative and posi- 
 tive elements are detached from one another. Crude iron contains more or less carbon, 
 sulphur, phosphorus, arsenic, oxygen, and silicon — bodies all electro- negative in rela- 
 tion to iron, which is electro-positive. When the impure iron, as it flows from the 
 blast-furnaces, is subjected during its cooling and consolidation to a powerful stream of 
 voltaic electricity, the chemical affinities by which its various heterogeneous components 
 are firmly associated are immediately subverted, whereby, in the case of crude iron, the 
 sulphur, phosphorus, &c, which destroy or impair its tenacity and malleability, become 
 readily separable in the act of puddling. On this principle, I would explain the extra- 
 ordinary effect of Mr. Wall's patent electric process, as performed in my presence in 
 the excellent iron-works of Mr. Jessop, at Codner Park, Derbyshire, where the elec- 
 trised forge pigs discharged those noxious elements so copiously in the puddling fur- 
 nace, as to become after a single re-heating, without piling or fagotting, brilliant bars 
 of the finest fibrous metal. The bars so made have been subjected, under my inspec- 
 tion, to the severest proofs by skilful London blacksmiths, and they have been found to 
 bear piercing, hammering, bending, and twisting, as well as the best iron in the mar- 
 ket. I have also analysed the said iron with the utmost minuteness of chemical 
 research, and have ascertained it to be nearly pure metal, containing neither sulphur 
 nor phosphorus, and merely an inappreciable trace of arsenic. I can therefore con- 
 scientiously recommend Mr. Wall's patent process to iron-masters as one of the greatest, 
 easiest, and most economical improvements, which that important art has ever received. 
 
 The pecuniary advantage of this process, in respect of saving of labour and waste of 
 material, has been estimated by competent judges at from one pound to two pounds 
 sterling per ton. 
 
 The effect of electrising iron is displayed in a singular manner by the conversion into 
 steel of a soft rod, exposed in contact with coke, for a few hours, to a moderate red 
 heat ; a result which I have witnessed and can fully attest. 
 
 PURPLE OF CASSIUS is best made according to the French Pharmacopoeia, 
 by dissolving 10 parts of acid chloride of gold in 2000 parts of distilled water ; prepar- 
 ing in another vessel a solution of 10 parts of pure tin in 20 of muriatic acid, which is 
 diluted with 1000 of water, and adding this by degrees to the gold solution as long as 
 a precipitate is formed. The precipitate is allowed to subside, and is to be washed by 
 means of decantation : it is then filtered and dried at a very gentle heat. 
 
 E. 
 
 REFINING OF SILVER. In this process, as effected by sulphuric acid, the 
 arrangements are so complete, that a two thousandth part, or even less, of gold is ex- 
 tracted free of charge to the bullion merchant, and the whole silver returned or ac- 
 counted for. By mistake, a one thousandth was stated in the article Refining op 
 Silver in the Dictionary. 
 
 RESINS. An ingenious memoir upon the resins of dammar, copal, and anime, 
 has lately been published by M. Guibourt, an eminent French jiharmacien, from which 
 the following extracts may be found interesting. 
 
 The hard copal of India and Africa, especially Madagascar, is the product of the 
 Hymencea verrucosa ; it is transparent and vitreous within, whatever may be its appear- 
 ance outside ; nearly colourless, or of a tawny yellow ; without taste or smell in the 
 cold, and almost as hard as amber, which it much resembles, but from which it may be 
 distinguished, 1st, by its melting and kindling at a candle-flame, and running down in 
 drops, while amber burns and swells up without flowing ; 2dly, this hard copal or 
 anime, when blown out and still hot, exhales a smell like balsam copaiva or capivi ; while 
 amber exhales an unpleasant bituminous odour; 3dly, when moistened by alcohol of 
 85 per cent., copal becomes sticky, and shows after drying a glazed opaque surface, 
 while amber is not affected by alcohol ; 4thly, the copal affords no succenic acid, as 
 amber does, on distillation. 
 
 When the pulverised copal is digested in cold alcohol of 0*830, it leaves a consider- 
 able residuum, at first pulverulent, but which swells afterwards, and forms a slightly 
 coherent mass. When this powder is treated with boiling alcohol, it assumes the con- 
 sistence of a thick gluten, like crumbs of bread, but which does not stick to the fingers. 
 Thus treated, it affords, 
 
 Resin soluble in cold alcohol - - - 31 '42 
 
 Resin dissolved in boiling alcohol - 4-00 
 Resin insoluble in both - - - - 65*71 
 
 100-83 
 
 The small excess is due to the adhesion of some of the menstruum to the resins. 
 
RETORTS OF CLAY. 
 
 209 
 
 Ether, boiling hot, dissolves 39-17 per cent, of copal. 
 
 Essence (spirits) of turpentine does not dissolve any of the copal, but it penetrates 
 and combines with it at a heat of 212° Fah. 
 
 The property of swelling, becoming viscid and elastic, which Berzelius assigns to 
 copal, belongs not to it, but to the American resin of courbaril, or the occidental 
 anime ; and the property of dissolving entirely in ether belongs to the aromatic dam- 
 mar, a friable and tender resin. 
 
 2. Resin of courbaril of Rio Janeiro, the English gum-anime, and the semi-hard 
 copal of the French. It is characterised by forming, in alcohol, a bulky, tenacious, 
 elastic mass. It occurs in rounded tears, has a very pale glassy aspect, transparent 
 within, covered with a thin white powder, which becomes glutinous with alcohol. 
 Another variety is soft, and dissolves, for the most part, in alcohol ; and a third re- 
 sembles the oriental copal so much as to indicate that they may both be produced from 
 the same tree. 1 00 parts of the oriental and the occidental anime yield respectively 
 the following residua : — 
 
 "With alcohol. With ether. "With essence. 
 
 Oriental - - 65-71 60.83 111 
 
 Occidental - - 43-53 27*50 75 "76 
 
 The hard and soft copals possess the remarkable property in common of becoming 
 soluble in alcohol, after being oxygenated in the air. 
 
 3. Dammar puti, or dammar batu. — This resin, soft at. first, becomes eventually 
 like amber, and as hard. It is little soluble in alcohol and ether, but more so in 
 essence of turpentine. 
 
 4. Aromatic dammar.- — This resin occurs in large orbicular masses. It is pretty 
 soluble in alcohol. Only small samples have hitherto been obtained. Of 100 parts, 3 
 are insoluble in alcohol, none in ether, and 93 in essence of turpentine. M. Guibourt 
 thinks that this resin comes from the Molucca isles. Its ready solubility in alcohol, 
 and great hardness, render it valuable for varnish -making. 
 
 5. Austral dammar. — This resin is the product of the Dammara australis, one of the 
 highest trees in New Zealand, where it is called Kauri, or Kouri, It resembles elemi 
 in some measure. It flows from the trunk and branches in the form of a resinous 
 juice called vare, and gum-cowdee by the English settlers. The natives chew it con- 
 tinually, and with the soot obtained from its combustion they make the indelible black 
 tattoo figures upon their faces. It comes home in lumps of considerable size. It pos- 
 sesses a certain toughness, which makes it difficult to break or to pulverise. It takes 
 fire at a candle flame, and continues to burn by itself. It melts in water, heated 
 below the boiling point. Alcohol boiled with it, leaves 43 -3 per cent, of insoluble 
 matter ; ether leaves 36*66 ; and essence of turpentine 80 per cent. This resin, in fact, 
 resembles very closely the resin of courbaril. 
 
 6. Slightly aromatic dammar leaves, after alcohol, 37 per cent.; after ether, 17 per 
 cent. ; and after essence, 87 per cent. 
 
 7. Tender and friable dammar selan. — This resin occurs in considerable quantity in 
 commerce (at Paris). It is in round or oblong tears, vitreous, nearly colourless and 
 transparent within, dull whitish on the surface. It exhales an agreeable odour of 
 olibanum, or mastic, when it is heated. It crackles with the heat of the hand, like 
 roll- sulphur. It becomes fluid in boiling water, but brittle when cooled again. It 
 sparkles and burns at the flame of a candle ; but this being the effect of a volatile oil, 
 the combustion soon ceases. 
 
 Resin soluble in cold alcohol - - - 75 "28 
 
 Resin insoluble in boiling alcohol - 20-86 
 
 It dissolves readily and completely in cold essence of turpentine, and forms a good 
 varnish. M. Guibourt refers the origin of this resin to the Dammara selanica of 
 Rumphius. Of the preceding resins, 100 parts have left respectively 
 
 Insoluble in 
 
 Alcohol of 0-830. Ether. Essence. 
 
 Hard copal, or anime - - 65*71 60*83 111 
 
 Tender copal - - - 43*53 27*50 75*76 
 
 Dammar puti — — — 
 
 Dammar aromatic 3'0 — 93 
 
 Dammar austral - 43*33 36*66 80 
 
 Dammar slightly aromatic - 37*00 17*00 87 
 
 Dammar friable - 20*86 2*00 — 
 
 RETORTS OF CLAY are now extensively used in gas-making, and they are well 
 manufactured at Newcastle. See the article Gas. 
 
210 
 
 SACCHAROMETER. 
 
 s. 
 
 SACCHAROMETER is the name of a hydrometer, adapted by its scale to point 
 out the proportion of sugar, or the saccharine matter of malt, contained in a solution of 
 any specific gravity. Brewers, distillers, and the Excise, sometimes denote by the term 
 gravity, the excess of weight of 1000 parts of a liquid by volume above the weight of a 
 like volume of distilled water ; so that if the specific gravity be 1045, 1070, 1090, &c, 
 the gravity is said to be 45, 70, or 90; at others, they thereby denote the weight of 
 saccharine matter in a barrel (36 gallons) of worts ; and again, they denote the excess 
 in weight of a barrel of worts over a barrel of water, equal to 36 gallons, or 360 pounds. 
 This and the first statement are identical, only 1000 is the standard in the first case, 
 and 360 in the second. 
 
 The saccharometer now used by the Excise, and by the trade, is that constructed by 
 Mr. R. B Bate, well known for the accuracy of his philosophical and mathematical 
 instruments. The tables published by him for ascertaining the values of wort or wash, 
 and low wines, are preceded by explicit directions for their use. " The instrument is 
 composed of brass ; the ball or float being a circular spindle, in the opposite ends of 
 which are fixed a stem and a loop. The stem bears a scale of divisions numbered 
 downwards from the first to 30 ; these divisions, which are laid down in an original 
 manner, observe a diminishing progression according to true principles ; therefore each 
 division correctly indicates the one thousandth part of the specific gravity of water; and 
 further, by the alteration made in the bulk of the saccharometer at every change of 
 poise, each of the same divisions continues to indicate correctly the said one thou- 
 sandth part throughout." 
 
 In my own practice, I prefer to take specific gravities of all liquids whatever with a 
 glass globe containing 500 or 1000 grains of distilled water at 60° Fahr., when it is 
 closed with a capillary-bored glass stopper ; and with the gravity so taken, I look into 
 a table constructed to show the quantity per cent, of sugar, malt, extract, or of any 
 other solid, proportional to the density of the solution. By bringing the liquid in the 
 gravity bottle to the standard temperature, no correction on this account is needed. 
 Mr Bate's elaborate table contains all these equations correctly for solutions of sugar 
 of every successive specific gravity. When employed in such researches by the Mo- 
 lasses Committee of the House of Commons in the year 1830, I found that the specific 
 gravities of solutions of the concrete extract of malt differed somewhat from those of 
 solutions of sugar, as given by Mr. Bate. ( See page 1 00. of the Dictionary. ) 
 
 The following Table shows the Quantities of Sugar contained in Syrups of the 
 annexed Specific Gravities. It was the result of experiments carefully made. 
 
 Experimental Spec. Gravity 
 of Solution at 60° F. 
 
 Sugar in 100* by 
 Weight. 
 
 Experimental Spec. Grav. 
 of Solution, at 60° F. 
 
 Sugar in 100* by 
 Weight. 
 
 1 -3260 
 
 66'666 
 
 1-1045 
 
 25 -000 
 
 1-2310 
 
 50-000 
 
 1 -0905 
 
 21*740 
 
 T1777 
 
 40-000 
 
 1 -0820 
 
 20-000 
 
 1 -4400 
 
 33-333 
 
 1 -0635 
 
 16-666 
 
 1 -1 340 
 
 31-250 
 
 1 -0500 
 
 12-500 
 
 1-1250 
 
 29-412 
 
 1 -0395 
 
 10-000 
 
 1-1110 
 
 26-316 
 
 
 
 N. B. The column in the opposite table, marked Solid extract by weight, is Mr. Bate's ; 
 it may be compared with this short table, and also with the table of malt infusions in 
 page 100. of the Dictionary. 
 
 If the decimal part of the number denoting the specific gravity of syrup be mul- 
 tiplied by 26, the product will denote very nearly the quantity of sugar per gallon in 
 pounds weight, at the given specific gravity.* 
 
 * This rule was annexed to an extensive table, representing the quantities of sugar per gallon, cor- 
 responding to the specific gravities of the syrups constructed by the Author, for the Excise, in subser- 
 viency to the Beet-root bill. 
 
SACCHAROMETER. 
 
 211 
 
 Table exhibiting the Quantity of Sugar, in Pounds Avoirdupois which is contained 
 in One Gallon of Syrup, at successive Degrees of Density, at 60° F. 
 
 Specific 
 Gravity, 
 
 Lbs. per 
 Gallon. 
 
 Extract 
 
 by 
 Weight 
 in 100. 
 
 Specific 
 Gravity. 
 
 Lbs. per 
 Gallon. 
 
 Extract 
 
 bvr 
 Weight 
 in 100. 
 
 Specific 
 Gravity. 
 
 Lbs. per 
 Gallon. 
 
 Specific 
 Gravity. 
 
 Lbs. per 
 Gallon. 
 
 1-000 
 
 0-0000 
 
 •0000 
 
 1-077 
 
 2-0197 
 
 •1851 
 
 1-154 
 
 4-0880 
 
 1-231 
 
 6-1474 
 
 1-001 
 
 0-0255 
 
 •0026 
 
 1-078 
 
 2-0465 
 
 •1^73 
 
 1-155 
 
 4-1148 
 
 1-232 
 
 6-1743 
 
 1-002 
 
 0 0510 
 
 •0051 
 
 1-079 
 
 2-0734 
 
 •J 896 
 
 1-156 
 
 4-1319 
 
 1-233 
 
 6 2012 
 
 1-003 
 
 0 0765 
 
 •0077 
 
 1-080 
 
 2-1006 
 
 •1918 
 
 1-157 
 
 4-1588 
 
 1-234 
 
 6-2280 
 
 1-004 
 
 0-1020 
 
 •0102 
 
 1-081 
 
 2-1275 
 
 •1941 
 
 1-158 
 
 4-1857 
 
 1235 
 
 6-2551 
 
 i-ooS 
 
 0-1275 
 
 •0128 
 
 1-082 
 
 2 1543 
 
 •1963 
 
 1-159 
 
 4-2128 
 
 1-236 
 
 6-2822 
 
 1-006 
 
 0-1530 
 
 •0153 
 
 1-083 
 
 2-1811 
 
 •1985 
 
 1-160 
 
 4-2502 
 
 1-237 
 
 6*3093 
 
 1-007 
 
 0-1785 
 
 •0179 
 
 1-084 
 
 2 2080 
 
 •2007 
 
 1-161 
 
 4-2771 
 
 1-238 
 
 6-3362 
 
 1-008 
 
 0-2040 
 
 •0204 
 
 1-085 
 
 2-2359 
 
 •2029 
 
 1162 
 
 4-3040 
 
 1-239 
 
 6-3631 
 
 1-009 
 
 0-2295 
 
 •0230 
 
 1-086 
 
 2-2627 
 
 •2051 
 
 1-163 
 
 4-3309 
 
 1-240 
 
 6-3903 
 
 1 010 
 
 0-2550 
 
 •0255 
 
 1-087 
 
 2-2894 
 
 •2073 
 
 1-164 
 
 4-3578 
 
 1-241 
 
 6-4152 
 
 1-011 
 
 0-2805 
 
 •0280 
 
 1-088 
 
 2-3161 
 
 •2095 
 
 1-165 
 
 4-3847 
 
 1-242 
 
 6-4401 
 
 1-012 
 
 0-3060 
 
 •0306 
 
 1-089 
 
 2-3438 
 
 •2117 
 
 1-166 
 
 4-4115 
 
 1-243 
 
 6-4650 
 
 1-013 
 
 03315 
 
 •0331 
 
 1-090 
 
 2-3710 
 
 •2139 
 
 1-167 
 
 4-4383 
 
 1-244 
 
 6-4902 
 
 1-014 
 
 0-3570 
 
 •0356 
 
 1-091 
 
 2-3987 
 
 •2161 
 
 1-168 
 
 4-4652 
 
 1-245 
 
 6-5153 
 
 1-015 
 
 0-3825 
 
 •0381 
 
 1-092 
 
 2-4256 
 
 •2183 
 
 1-169 
 
 4-4923 
 
 1-246 
 
 6-5402 
 
 1-016 
 
 0-4180 
 
 •0406 
 
 1-093 
 
 2-4524 
 
 •2205 
 
 1-170 
 
 4-5201 
 
 1-247 
 
 6-5651 
 
 1-017 
 
 0-4335 
 
 •0431 
 
 1-094 
 
 2-4792 
 
 •2227 
 
 1-171 
 
 4-5460 
 
 1-248 
 
 6-5903 
 
 1-018 
 
 0-4590 
 
 •0456 
 
 1-095 
 
 2-5061 
 
 •2249 
 
 1-172 
 
 4-5722 
 
 1-249 
 
 6-6152 
 
 1-019 
 
 0-4845 
 
 •0481 
 
 1-096 
 
 2-5329 
 
 •2270 
 
 1-173 
 
 4-5983 
 
 1-250 
 
 6-6402 
 
 1-020 
 
 05100 
 
 •0506 
 
 1-097 
 
 2 5598 
 
 •2292 
 
 1-174 
 
 4-6242 
 
 1-251 
 
 6-6681 
 
 1-021 
 
 0-5351 
 
 •0531 
 
 1098 
 
 2-5866 
 
 •2314 
 
 1-175 
 
 4-6505 
 
 1-252 
 
 6 6960 
 
 1-022 
 
 0 5602 
 
 •0555 
 
 .1-099 
 
 2-6130 
 
 •2335 
 
 1176 
 
 4 6764 
 
 1-253 
 
 6-7240 
 
 1-023 
 
 05853 
 
 •0580 
 
 rioo 
 
 2-6404 
 
 •2357 
 
 1-177 
 
 4-7023 
 
 1-254 
 
 6-7521 
 
 1-024 
 
 0-6104 
 
 •0605 
 
 1-101 
 
 2 6663 
 
 •2378 
 
 1-178 
 
 4-7281 
 
 1-255 
 
 6-7800 
 
 1-025 
 
 06355 
 
 •0629 
 
 1-102 
 
 2-6921 
 
 •2400 
 
 1179 
 
 4-7539 
 
 1256 
 
 68081 
 
 1-026 
 
 0-6606 
 
 •0654 
 
 1-103 
 
 2-7188 
 
 •2421 
 
 1-180 
 
 4-7802 
 
 1 257 
 
 6-8362 
 
 1-027 
 
 0 6857 
 
 •0678 
 
 1-104 
 
 2-7446 
 
 •2443 
 
 1-181 
 
 4-8051 
 
 1-258 
 
 6-8643 
 
 1-028 
 
 0-71(18 
 
 •0703 
 
 1-105 
 
 2-7704 
 
 •2464 
 
 1-182 
 
 4-8303 
 
 1-259 
 
 6-8921 
 
 1-029 
 
 0-7359 
 
 ■0727 
 
 1-106 
 
 2-7961 
 
 •2486 
 
 1-183 
 
 4-8554 
 
 1-260 
 
 6-9201 
 
 1-030 
 
 0-7610 
 
 •0752 
 
 1107 
 
 2 8227 
 
 •2507 
 
 1184 
 
 4-8802 
 
 1-261 
 
 6-9510 
 
 1 031 
 
 0-7861 
 
 •0776 
 
 1-108 
 
 2-8485 
 
 •2529 
 
 1-185 
 
 4 9051 
 
 1-262 
 
 6-9822 
 
 1032 
 
 08112 
 
 •0800 
 
 1-109 
 
 2-8740 
 
 •2550 
 
 1-186 
 
 4-9300 
 
 1-263 
 
 7-0133 
 
 1-033 
 
 0-8363 
 
 •0825 
 
 1-110 
 
 2-9001 
 
 •2571 
 
 1-187 
 
 4-9552 
 
 1-264 
 
 7-0444 
 
 1-034 
 
 0-8614 
 
 •0849 
 
 1-111 
 
 2-9263 
 
 •2593 
 
 1-188 
 
 4-9803 
 
 1-265 
 
 7-0751 
 
 1 035 
 
 0 8866 
 
 •0873 
 
 1-112 
 
 2-9522 
 
 •2614 
 
 1-189 
 
 5 0054 
 
 1-266 
 
 7- 1060 
 
 1-036 
 
 0-9149 
 
 •0897 
 
 1-113 
 
 2-9780 
 
 •2635 
 
 1-190 
 
 5.0304 
 
 1-267 
 
 7-1369 
 
 1-037 
 
 0-9449 
 
 •0921 
 
 1-114 
 
 3-0045 
 
 •2656 
 
 1-191 
 
 5-0563 
 
 1-268 
 
 7-1678 
 
 1-038 
 
 0-9768 
 
 •0945 
 
 1-115 
 
 3-0304 
 
 •2677 
 
 1-192 
 
 5 0822 
 
 1-269 
 
 7-1988 
 
 1039 
 
 1-0090 
 
 •0969 
 
 1-116 
 
 3-0563 
 
 •2698 
 
 1193 
 
 5-1080 
 
 1 270 
 
 7-2300 
 
 1-040 
 
 1-0400 
 
 •0993 
 
 1-117 
 
 3-0821 
 
 •2719 
 
 1-194 
 
 5-1341 
 
 1 271 
 
 7-2601 
 
 1-041 
 
 1-0653 
 
 •1017 
 
 1 -118 
 
 3- 1080 
 
 •2740 
 
 1-195 
 
 5-1602 
 
 1-272 
 
 7-2902 
 
 1-042 
 
 1 -0906 
 
 •1041 
 
 1-119 
 
 3- 1343 
 
 •2761 
 
 1-196 
 
 5-1863 
 
 1-273 
 
 7-3204 
 
 1043 
 
 1-1159 
 
 •1065 
 
 1-120 
 
 3-1610 
 
 •2782 
 
 1-197 
 
 5-2124 
 
 1-274 
 
 7-3506 
 
 1044 
 
 1-1412 
 
 •1089 
 
 1-121 
 
 3-1871 
 
 •2803 
 
 1-198 
 
 5-2381 
 
 1-275 
 
 7-3807 
 
 1-045 
 
 1-1665 
 
 •1113 
 
 1-122 
 
 3-2130 
 
 •2824 
 
 1-199 
 
 5-2639 
 
 1-276 
 
 7-4109 
 
 1046 
 
 1-1918 
 
 •1136 
 
 1-123 
 
 3-2399 
 
 •2845 
 
 1-200 
 
 5-2901 
 
 1-277 
 
 7 4409 
 
 1-047 
 
 1-2171 
 
 •1160 
 
 11 24 
 
 3-2658 
 
 •2865 
 
 1-201 
 
 5-3160 
 
 1-278 
 
 7-4708 
 
 1-048 
 
 1-2424 
 
 •1184 
 
 1-125 
 
 3-2916 
 
 •2886 
 
 1-202 
 
 5-3422 
 
 1-279 
 
 7-5007 
 
 1-049 
 
 1-2687 
 
 •1207 
 
 1-126 
 
 3-3174 
 
 •2907 
 
 1-203 
 
 5-3681 
 
 1-280 
 
 7-5307 
 
 1-050 
 
 1-2940 
 
 •1231 
 
 1-127 
 
 3-3431 
 
 •2927 
 
 1-204 
 
 5-3941 
 
 1-281 
 
 7-5600 
 
 1-051 
 
 1-3206 
 
 •1254 
 
 1-128 
 
 3 3690 
 
 •2948 
 
 1-205 
 
 5-4203 
 
 1-282 
 
 7-5891 
 
 1-052 
 
 1-3472 
 
 •1278 
 
 1-129 
 
 3-3949 
 
 •2969 
 
 1-206 
 
 5 4462 
 
 1-283 
 
 7-61 SO 
 
 1-053 
 
 1-3738 
 
 •1301 
 
 1-130 
 
 3 4211 
 
 •2989 
 
 1-207 
 
 5 4720 
 
 1-284 
 
 7-6469 
 
 1-054 
 
 1-4004 
 
 •1325 
 
 1-131 
 
 3-4490 
 
 •3010 
 
 1-208 
 
 5-4979 
 
 1-285 
 
 7-6758 
 
 1-055 
 
 1-4270 
 
 •1348 
 
 1-132 
 
 3-4769 
 
 •3030 
 
 1-209 
 
 5-5239 
 
 1-286 
 
 7 7048 
 
 1-056 
 
 1-4536 
 
 •1372 
 
 1-133 
 
 3-5048 
 
 •3051 
 
 1-210 
 
 5-5506 
 
 1-287 
 
 7-7331 
 
 1-057 
 
 1-4802 
 
 •1395 
 
 1-134 
 
 3-5326 
 
 •3071 
 
 1-211 
 
 5-5786 
 
 1-288 
 
 7*7620 
 
 1-058 
 
 1-5068 
 
 •1418 
 
 1-135 
 
 3-5605 
 
 •3092 
 
 1-212 
 
 5 6071 
 
 1-289 
 
 7-7910 
 
 1*059 
 
 1'5334 
 
 •1441 
 
 1-136 
 
 3" 5882 
 
 •3112 
 
 1-213 
 
 5-6360 
 
 1-290 
 
 7-8201 
 
 i-oco 
 
 1-5600 
 
 •1464 
 
 1-137 
 
 3-6160 
 
 •3132 
 
 1-214 
 
 5-6651 
 
 1-291 
 
 7-8482 
 
 1-061 
 
 1-5870 
 
 •1487 
 
 1-138 
 
 3-6437 
 
 •3153 
 
 1-215 
 
 5 6942 
 
 1-292 
 
 7 8763 
 
 1-062 
 
 1-6142 
 
 •1510 
 
 1139 
 
 3 6716 
 
 •3173 
 
 1-216 
 
 5 7233 
 
 1-293 
 
 7-9042 
 
 1063 
 
 1-6414 
 
 •1533 
 
 1-140 
 
 3-7000 
 
 •3193 
 
 1-217 
 
 5-7522 
 
 1-294 
 
 7 9321 
 
 1-064 
 
 1-6688 
 
 •1556 
 
 11 41 
 
 3-7281 
 
 •3214 
 
 1-218 
 
 5-7814 
 
 1-295 
 
 7-9600 
 
 1-065 
 
 1-6959 
 
 •1579 
 
 1-142 
 
 3-7562 
 
 •3234 
 
 1219 
 
 5-8108 
 
 1-296 
 
 7-9879 
 
 1066 
 
 1-7228 
 
 •1602 
 
 1143 
 
 3-7840 
 
 •3254 
 
 1-220 
 
 5-8401 
 
 1-297 
 
 8-0158 
 
 1-067 
 
 1-7496 
 
 •1625 
 
 1-144 
 
 3-8119 
 
 •3274 
 
 1-221 
 
 5-8680 
 
 1-298 
 
 8-0448 
 
 1-068 
 
 1-7764 
 
 •1647 
 
 1145 
 
 3-8398 
 
 •3294 
 
 1-222 
 
 5-8962 
 
 1-299 
 
 8 0719 
 
 1069 
 
 1-8033 
 
 •1670 
 
 1-146 
 
 3-8677 
 
 •3314 
 
 1-223 
 
 5-9242 
 
 1-300 
 
 8-1001 
 
 1-070 
 
 1-8300 
 
 •1693 
 
 1-147 
 
 3-8955 
 
 •3334 
 
 L224 
 
 5-9523 
 
 
 1-071 
 
 1-8571 
 
 •1716 
 
 1-148 
 
 3-9235 
 
 •3354 
 
 1-225 
 
 5-9801 
 
 
 
 1-072 
 
 1-8843 
 
 •1738 
 
 1-149 
 
 3-9516 
 
 •3374 
 
 1-226 
 
 6-0081 
 
 
 
 1-073 
 
 1-9116 
 
 •1761 
 
 1-150 
 
 3-9801 
 
 •3394 
 
 1-227 
 
 6-0361 
 
 
 
 1-074 
 
 1-9385 
 
 •1783 
 
 1-151 
 
 4-0070 
 
 
 1-228 
 
 6-0642 
 
 
 
 1-075 
 
 1-9653 
 
 •1806 
 
 1-152 
 
 4-0342 
 
 
 1-229 
 
 6-0925 
 
 
 
 1-076 
 
 1-9928 
 
 •1828 
 
 1-153 
 
 4-0611 
 
 
 1-230 
 
 6-1205 
 
 
 
 E e 2 
 
212 
 
 SILK. 
 
 SAFETY LAMP. During a visit which I paid to Newcastle some time ago, I 
 took pains to learn the opinion of the best judges of coal mining, upon the merits of the 
 patent invention of Upton and Roberts, described in the Dictionary, and I found from 
 the concurring testimony of that very able engineer, Mr. Buddie, since lost to his 
 friends and the world, and of Mr. Sopwith, well known for the geological study of the 
 coal formation, that the said lamp could not be safely used on account of its glass case, 
 which, being most liable to break, would be apt to cut or rupture the meshes of the 
 wire gauze within it. and thus to lay the flame open for explosions. It is not therefore 
 in use. 
 
 SAGO. See Pepper in this Supplement. 
 
 SAL AMMONIAC. A patent was obtained in 1840, for improvements in the 
 manufacture of this article, by Mr. H. Waterton. Two modes of operating are de- 
 scribed ; the first consists in making a saturated solution of common salt in water, and 
 mixing with it a quantity of finely pulverised carbonate of ammonia, about equal in 
 weight to the salt contained in the solution. The mixture is agitated in a close vessel 
 for six or eight hours, and as much carbonic acid gas is infused therein as it will absorb 
 (but the introduction of the gas is not absolutely necessary, although the patentee pre- 
 fers it) ; the liquid is then separated from the solid matter, by filtration and pressure. 
 The solid matter is chiefly bi-carbonate of soda, and the liquid holds in solution mu- 
 riate and carbonate of ammonia, and common salt, and sometimes a small portion of 
 the bi-carbonate of soda.. 
 
 The liquid is now placed in a distilling vessel, and the carbonate of ammonia being 
 distilled over into a suitable receiver, a solution of muriate of ammonia and common salt 
 remains in the still. This solution is evaporated, by heat, to such a consistency as will 
 cause the separation of the common salt, by crystallisation, and the salt, thus crys- 
 tallised, is evaporated from the liquid by any convenient method. The liquid is then 
 evaporated until it attains the proper specific gravity for crystallising, and it is transferred 
 into suitable utensils for that purpose. The crystals, produced by these means, are nearly 
 pure muriate of ammonia, and, when pressed and dried, may be brought to market 
 without further preparation, or they may be sublimed into cake sal ammoniac. 
 
 The other mode of manufacturing sal ammoniac consists in taking a quantity of 
 liquid, containing ammonia, either in the caustic state, or combined with carbonic, hy- 
 drosulphuric, or hydrocyanic acid (such as gas ammoniacal liquor, or bone ammoniacal 
 liquor), and rectifying it, by distillation, until the distilled portion contains from twenty 
 to twenty-five per cent, of carbonate of ammonia. If the liquid contains any other 
 acids than those above mentioned, a sufficient quantity of lime is used in the distillation 
 to decompose the ammoniacal salt. 
 
 The distilled liquid being now mixed with as large a quantity of powdered common 
 salt as it will dissolve, is agitated for several hours, and as much carbonic acid gas is 
 infused into it as it will absorb. The remainder of the operation is the same as before 
 described in the first method of manufacturing sal ammoniac. — Newton's Journal, C. S. 
 xxii. 35. 
 
 SEMOULE. The name given in France, and used in this country, to denote the 
 large hard grains of wheat flour retained in the bolting machine after the fine flour has 
 been passed through its meshes. The best semoule is obtained from the wheat of the 
 southern parts of Europe. With the semoule, the fine white Parisian bread called 
 gruau is baked. Skilful millers contrive to produce a great proportion of semoule 
 from the large-grained wheat of Naples and Odessa. 
 
 SILK. Several pieces of silk were put into my hands, for analysis, on the 18th of 
 February, after I had, on the preceding 1 2th of the month, visited the St. Katharine's 
 Dock Warehouses, in New Street, Bishopsgate Street, for the purpose of inspecting a 
 large package of the Corahs, per Colonist. I was convinced, by this inspection, that, 
 notwithstanding the apparent pains bestowed upon the tin plate and teak wood packing- 
 cases, certain fissures existed in them, through which the atmospheric air had found 
 access, and had caused iron-mould spots upon the gunny wrapper, from the rusting or 
 oxidizement of the tinned iron. 
 
 I commenced my course of analysis upon some of the pieces which were most 
 damaged, as I thought they were most likely to lead me to an exact appreciation of 
 the cause of the mischief; and I pursued the following general train of research: — 
 
 1. The piece of silk, measuring from 6 to 7 yards, was freely exposed to the air, then 
 weighed, afterwards dried near a fire, and weighed again, in order to determine its 
 hygrometric property, or its quality of becoming damp by absorbing atmospheric 
 vapour. Many of the pieces absorbed, in this way, from one-tenth to one-eighth of 
 their whole weight; that is, from 1 oz to \\ oz. upon 13 oz. This fact is very in- 
 structive, and shows that the goods had been dressed in the loom, or imbued sub- 
 sequently, with some very deliquescent pasty matter. 
 
 2. I next; subjected the piece to the action of distilled water, at a boiling tempera- 
 
SILK. 
 
 2m 
 
 ture, till the whole glutinous matter was extracted ; five pints of water were employed 
 for this purpose, the fifth being used in rinsing out the residuum. The liquid wrung 
 out from the silk was evaporated first over the fire, but towards the end over a steam 
 bath, till it became a dry extract ; which in the damaged pieces was black, like extract 
 of liquorice, but in the sound pieces was brown. In all cases, the extract so obtained 
 absorbed moisture with great avidity. The extract was weighed in its driest state, and 
 the weight noted, which showed the addition made, by the dressing, to the weight of 
 the silk. The piece of silk was occasionally weighed in its cleansed state, when dry, 
 as a check upon the preceding experiment. 
 
 3. The dry extract was now subjected to a regular chemical analysis, which was 
 modified according to circumstances, as follows: — 100 parts of it were carefully 
 ignited in a platinum capsule ; during which a considerable flame and fetid smoke were 
 disengaged. The ashes or incombustible residuum were examined by the action of 
 distilled water, filtration, as also by that of acids, and other chemical tests, whereby the 
 constituents of these ashes were ascertained. In the course of the incineration or cal- 
 cination of the extract from the several samples, I never observed any sparkling or scin- 
 tillation ; whence I inferred that no nitre had been used in the dressing of the goods, 
 as some persons suggested. 
 
 4. Having, in the course of boiling some of the extract from two of the damaged 
 pieces, in a little distilled water, felt a urinous odour, I was induced to institute the 
 following minute course of researches, in order to discover whether the urine of man 
 had been introduced into the dressing paste of the silk webs. I digested a certain 
 portion of the said extract in alcohol, 60 per cent, over proof, which is incapable of dis- 
 solving the rice water, or other starchy matter, which might be properly applied to the 
 silk in the loom. The alcohol, however, especially when aided by a moderate heat, 
 readily dissolves urea, a substance of a peculiar nature, which is the characteristic con- 
 stituent of human urine. The alcohol took a yellow tint, and, being after subsidence 
 of the sediment, decanted clear off into a glass retort, and exposed to the gentle heat of 
 a water bath, it distilled over clear into the receiver, and left a residuum in the retort, 
 which possessed the properties of urea. This substance was solid when cold, but 
 melted at a heat of 220° F. ; and at a heat of about 245° it decomposed with the pro- 
 duction of water and carbonate of ammonia — the well-known products of urea at that 
 temperature. The exhalation of the ammonia was very sensible to the smell, and was 
 made peculiarly manifest by its browning yellow turmeric paper, exposed in a moist 
 state to the fumes, as they issued from the orifice of the glass tube, in which the de- 
 composition was usually effected. I thus obtained perfect evidence that urine had 
 been employed in India in preparing the paste with which a great many of the pieces 
 had been dressed. It is known to every experienced chemist, that one of the most 
 fermentative or putrefactive compositions which can be made, results from the mixture 
 of human urine with starchy or gummy matter, such as rice water ; a substance which, 
 by the test of iodine water, these Corahs also contained, as I showed to the gentlemen 
 present, at my visit to the Bonding Warehouse. 
 
 5. On incinerating the extract of the Corahs, I obtained, in the residuum, a notable 
 quantity of free alkali ; which, by the test of chloride of platinum, proved to be potassa. 
 But, as the extract itself was neutral to the tests of litmus and turmeric paper, I was 
 consequently led to infer, that the said extract contained some vegetable acid, probably 
 produced by the fermentation of the weaver's dressing, in the hot climate of Hindostan. 
 I, accordingly, examined the nature of this acid, by distilling a portion of the extract 
 along with some very dilute sulphuric acid, and obtained, in the receiver, a notable 
 quantity of the volatilised acid condensed. This acid might be the acetic (vinegar), 
 the result of fermentation, or it might be the formic or acid of ants, the result of the 
 action of sulphuric acid upon starchy matter. To decide this point, I saturated the 
 said distilled acid with magnesia, and obtained on evaporation the characteristic gummy 
 mass of acetate of magnesia, soluble in alcohol, but none of the crystals of formiate of 
 magnesia, insoluble in alcohol. From the quantity of alkali (potassa) which I obtained 
 from the incineration of the extract of one piece of the damaged silk, and which 
 amounted to six grains at least, I was convinced that wood ashes had been added, in 
 India, to the mixture of sour rice water and urine, which would therefore constitute a 
 compound remarkably hygrometric, and well qualified to keep the warp of the web 
 damp, even in that arid atmosphere, during the time that the Tanty or weaver was 
 working upon it. The acetate of potassa, present in the said Corahs, is one of the 
 most deliquescent salts known to the chemist : and, when mixed with fermented urine, 
 forms a most active hygrometric dressing, — one, likewise, which will readily generate 
 mildew upon woven goods, with the aid of heat and the smallest portion of atmospheric 
 oxygen. By the above-mentioned fermentative action, the carbon, which is one of the 
 chemical constituents of the rice or starchy matter, had been eliminated, so as to occa- 
 
f 14 
 
 SILK. 
 
 sion the dark stains upon the silk, and the blackness of the extract taken out of it by 
 distilled water. 
 
 6. That the dressing applied to the webs is not simply a decoction of rice, becomes 
 very manifest, by comparing the incinerated residuum of rice with the incinerated re- 
 siduum of the extract of the said Corahs. I find that 100 grains of rice, incinerated 
 in a platinum capsule, leave only about one fifth of a grain, or 1 in 500 of incombustible 
 matter, which is chiefly silicious sand; whereas, when 100 grains of an average extract 
 of several of these Corahs were similarly incinerated, they left fully 17 parts of incom- 
 bustible matter. This consisted chiefly of alumina or earth of clay, with silica, potassa, 
 and a little common or culinary salt. (Has the clay been added, as is done in Man- 
 chester, to give apparent substance to the thin silk web?) 
 
 From the above elaborate course of experiments, which occupied me almost con- 
 stantly during a period of four weeks, I was fully warranted to conclude that the 
 damage of the said goods had been occasioned by the vile dressing which had been put 
 into them in India; which, as I have said, under the influence of heat and air, had 
 caused them to become more or less mildewed, in proportion to their original damp- 
 ness when packed at Calcutta, and to the accidental ingress of atmospheric air into the 
 cases during the voyage from Calcutta to London. 
 
 The following is the list of Corahs which I chemically examined : — 
 
 1 and 2, per Colonist, from Calcutta, 2 pieces, sound. — These two pieces had been 
 dressed with a sweet viscid matter, like jaggery or goor (molassy sugar), mixed with 
 the rice water. This extract contained no urine, but emitted a smell of caramel or 
 burned sugar, when ignited. It amounted to 270 grains in the one, and 370 in the 
 other. 
 
 3, ditto, 1 piece, mildewed, 1st degree. — This piece had been dressed like No. 5, 
 and contained no trace of urine. It afforded 400 grains of a most deliquescent sweetish 
 glutinous matter. 
 
 4, ditto, 1 piece, mildewed, 1st degree, as No. 3. 
 
 5, ditto, 1 piece, mildewed, 3d degree. — This piece contained no trace of urine, 
 but it afforded 210 grains of a light brown extract, being rice water, mixed with some- 
 thing like jaggery. 
 
 6, ditto, 1 piece, 3d degree, mildewed. — This piece afforded evidence of urine in it, 
 by test of carbonate of ammonia. The extract amounted to 320 grains. 
 
 8, ditto, 2 pieces, damaged in the 3d degree. — The total weight of one of these 
 pieces, after exposure to air, was 4610 grains, and it lost 440 grains by drying. The 
 total weight of the other was 4950 grains, and it lost 320 grains by drying. The weight 
 of extract was, in one piece, 210 grains ; and both pieces contained abundant traces of 
 urine, as well as of potash. These constituents, along with the rice water, accounted 
 sufficiently for the great damage of these two pieces by mildew. 
 
 10, ditto, 2 pieces, sound. — These contained no urea. Each afforded from 300 to 
 500 grains, of a light brown vegetable extract. 
 
 12, ditto, 2 pieces. — The extract in the one amounted to 222 grains, and in the 
 other to 330. Both contained urea, and had, therefore, been imbued with urine. 
 
 14, ditto, 2 pieces, mildewed, 3d degree. — There was no urea in the extracts from 
 these two pieces ; but they afforded, the one 300 grains of extract, and the other 750. 
 But this extract was a saccharine molassy matter, impossible to dry over a steam heat. 
 The same quantity as the last, if dried by stronger means, would have weighed pro- 
 bably 600 grains. Its extraordinary deliquescence kept the pieces very moist, and 
 thereby caused the mildewing of them. With the saccharine matter, four per cent, of 
 culinary salt was mixed in one of these extracts. 
 
 1 6, ditto, 2 pieces, 3d degree of mildew. — The extract, about 200 grains, contained 
 abundant evidence of urea, and consequently, of urine. 
 
 18, ditto, 2 pieces, sound. — Both these contained some traces of urea ; but the one 
 yielded only 102 grains of extract, and the other 370 grains. They must have been 
 well screened from the air to have resisted the action of the urine. 
 
 20, ditto, 2 pieces, damaged, 1st degree. — No urea. The extract of the one was 
 320 grains ; of the other piece 380 ; and it had a light brown colour, being a saccha- 
 rine mucilage. 
 
 22, ditto, 2 pieces, 3d degree mildew. — 200 grains of extract in the one, and 210 
 in the other : they contained urea. 
 
 24, 2 pieces, 3d degree of mildew. — 310 grains of extract in the one, and 180 
 grains in the other. Both Avere impregnated with urea, and consequently with urine. 
 
 Having in the preceding report demonstrated, by the clearest processes of chemical 
 research, that the above mildewed Corahs had been damaged by the fermentative de- 
 composition of the dressing paste with which they had been so abundantly impregnated, 
 I would recommend the importers of such goods to cause the whole of the dressing to 
 be washed out of them, and the pieces to be thoroughly dried before being packed up. 
 
SILVER. 
 
 215 
 
 T believe that clean silk may be kept and transported, even in the most humid atmo- 
 sphere, without undergoing any change, if it be not imbued with fermentative paste. 
 
 I examined eight other pieces of a different mark, imported by another mercantile 
 house, per Colonist, and they afforded results similar to the above. 
 
 SILVER, Extraction of from Lead ; Pattinsons process. — The desilverizing appa- 
 ratus of Locke, Blackett and Co., consists of seven crystallizing pots, and one smaller 
 pot for receiving the desilverized lead. They are all made of cast iron, and arranged 
 
 in a straight line. * 
 
 The lead in each pot varies in its contents of silver. 
 
 oz. oz. 
 
 The first containing 85 cwt. lead at about 60 oz. of silver, or per ton - 255 
 Is divided into 55 cwt. crystals carried to second pot, at 35 oz. per ton - 96 
 18 cwt. do. to be put in first pot again, at 64 oz. per ton - 57 
 and 12 cwt. rich lead to be cupelled, at 170 oz. per ton - - 102 
 
 255 
 
 The second pot containing 90 cwt. lead, at about 35 oz. silver per ton - 157 
 Is divided into 60 cwt. crystals carried to third pot, at 20 oz. per ton - 60 
 and 30 cwt. lead put into first pot, at 65 oz. per ton - 97 
 
 157 
 
 The third pot containing 90 cwt. of lead, at about 20 oz. per ton - - 90 
 Is divided into 55 cwt. crystals carried to fourth pot, at 10 oz. per ton - 27 
 and 25 cwt. lead put into second pot, at 36 oz. per ton - - 63 
 
 90 
 
 The fourth pot containing 80 cwt. lead, at about 10 oz. per ton - 40 
 Is divided into 55 cwt. crystals, carried to fifth pot, at 51 oz. per ton - ] 5 
 and 25 cwt. lead put into third pot, at 20 oz. per ton - - 25 
 
 40 
 
 The fifth pot containing 80 cwt. lead, at about 5\ oz. silver per ton - 22 
 Is divided into 55 cwt. crystals, put into sixth pot, at 3 oz. per ton 8\ 
 and 25 cwt. lead, put into fourth pot, at 1 1 oz. per ton - - 1 3| 
 
 22 
 
 The sixth pot containing 80 cwt. lead, at about 3 oz. per ton - 12 
 
 Is divided into 55 cwt. crystals, carried to seventh pot, at 1| oz. per ton - 4± 
 and 25 cwt. lead, put into fifth pot, at 6 oz. per ton - - 1\ 
 
 12 
 
 The seventh pot containing 55 cwt. lead, at about l|oz. per ton - 4 
 Is divided into 25 cwt. crystals, carried to small pot, at \ oz. per ton ■• \ 
 and 30 cwt. lead, put into sixth pot, at 2± oz. per ton - - 3| 
 
 4 
 
 The above 25 cwt. of crystals are melted and cast into pigs and sent to the market. 
 
 In operating upon lead containing about 10 oz. per ton, the fourth pot is filled with 
 it; if it should contain 20 oz., or thereabouts, it is put into the third pot; and so of 
 any other. 
 
 Fig. 125. represents the arrangement of the iron pots or cauldrons, in their order. 
 
 
 r. ~ n 
 
 1; !'' 1 ] 
 
 ' 1 • 1 ■ : 1 ' 1 : 1 
 
 ! ■ 1 ! -1 : 1. I> 
 
 
 125 
 
 i 
 
 i 
 
 i 
 
 
 ' ! 1 
 
 1 
 
 
 
 1 — ' ■ III ■ 
 
 The desilvering apparatus represented in fig. 125. is composed of five cauldrons of 
 cast iron, each heated by its own fire, besides two smaller pots, similarly heated. The 
 cauldrons rest by their upper flange and surface upon bricks properly formed and 
 arranged. Their shape is not hemispherical ; their mouth is 40 inches in length, but 
 only 26 inches in width. Over the door of the fireplace, the mouth stands 8 feet 
 4 inches above the ground or bottom of the ash-pit, of which space, 18 inches intervene 
 
216 
 
 SMELTING IRON FURNACES. 
 
 between the grate and the brim. The grate is 2 feet long and 8f inches wide. All 
 the cauldrons have the same elliptic form, with a bottom like the small end of an egg. 
 The fifth alone is smaller, but this one serves merely to melt the lead which has been 
 stript of its silver, in order to be cast into salmons or blocks. 
 
 The charge consists of 64 or 65 salmons, each weighing from 120 to 140 lbs. When 
 they are well melted, the fire is removed from the grate, as well as the small film of 
 litharge from the surface of the metal ; and one or two salmons are added to accelerate 
 the cooling, or sometimes, instead, a little soapy water is sprinkled' into the cauldron, 
 whereby a crust of lead is formed, which being pushed down into the mass, melts with 
 ebullition. This is repeated till the whole becomes sufficiently cool, that is, when 
 crystals begin to form. The lead concreted round the sides being now detached, the 
 whole is stirred with an iron bar, by a motion in a vertical plane, and varying its 
 posture in this plane. During this operation, intended to establish a uniform tempera- 
 ture throughout the mass, a second workman heats in the smaller pot adjoining to 
 No. 1. a large skimmer at the end of a long wooden handle, and next proceeds to fish 
 out the crystals, taking care to let them drain off for a few seconds all the liquid lead 
 among them, and then turns out the crystals slowly into the next cauldron, No. 2. ; 
 the second workman meanwhile adds the metal solidified round the sides, and stirs all 
 together to equalise the temperature. These two-fold operations occupy about fifty 
 minutes ; by which time, there remains in the cauldron about 16 salmons. The workman 
 now lifts out the crystals, as before, with the^ drainer, and throws them upon the ground 
 in two heaps. His assistant takes them up a little while afterwards, and puts them 
 away to make room for fresh crystals, which the first workman continues to throw 
 down. This process goes on till only 8 salmons remain in the cauldron, a point 
 ascertained by gauging the height to the bath. The fire being at this time removed 
 from cauldron No. 2. into the grate of No. 1. the 8 salmons of lead enriched with silver, 
 which remain at the bottom of the cauldron, are run out into movable moulds ; and the 
 8 salmons which were thrown upon the ground are put into it ; the full charge being 
 then made up with salmons of the same richness as those previously used. 
 
 While this mass is melting in No. 1. the process just finished in it is repeated in 
 No. 2. About three-fourths of the metallic mass is next separated in the state of 
 crystals, which are transferred to No. 3. and also one-eighth of crystals thrown on the 
 ground, after pouring the remaining one-eighth at the bottom of cauldron No. 2. not 
 into moulds, but into No. h 
 
 A like process is performed in cauldrons 3. and 4. ; and the poor lead taken out of 4. 
 is transferred to 5. to be melted, and run into salmons, which are submitted afresh to the 
 preceding series of crystallizations, provided the lead still contains a sufficient proportion 
 of silver. 
 
 The following Table will place the results of the above successive operations in a 
 clear light : — 
 
 Silver in 1 Ton of Lead. 
 Original lead ----- 0-001153 
 
 1. Rich crystals - 0*003324 
 
 2. Poor ditto ----- 0-000933 
 — Rich ditto "^proceeding from the treatment of the preced- |* 0 0020802 
 
 3 Poor ditto. J ing No. 2. poor crystals - - \ 0*0007021 
 
 4. Rich "1 proceeding from the treatment of No. 3. poor f 0*001399 
 
 —Poor J crystals - - - - \ 0*0004569 
 
 —Rich "I . r XT . f 0*0008135 
 
 , r Y as above from No. 4. - < „ „„„ , . 00 
 
 (Lead) poor J ^ 0*0001128 
 
 We thus see, that four crystallizations, repeated upon the original lead from the 
 smelting furnace, of the above richness, will afford a lead ten times poorer. With a 
 lead originally containing only 0*0002248 in silver, three crystallizations would suffice 
 to make it ten times poorer. In general, the poorer the lead, within certain limits, the 
 better adapted is it to this process. 
 
 SILVERING. See Electrotype. 
 
 SLIDES. The name given by the Cornish miners to clay veins of more modern 
 formation. 
 
 SMELTING IRON FURNACES, commonly called BLAST FURNACES. 
 Several of these furnaces, as mounted near Glasgow, deserve to be made known, on 
 account of the economy of their construction, the advantage of their form, and the 
 amount of their performance. 
 
 Fig. 1 26. represents one of the smallest of these, which measures from the line at the 
 bottom to the top 48 feet, from which all the other dimensions may be estimated. It 
 produces a soft cast-iron for casting into moulds and for melting in the cupola. Figs. 
 127. and 128. represent a much larger furnace, being from the top, to the line A, B, C, D, 
 
SMELTING IRON FURNACES. 
 
 217 
 
 60 feet high. A few have heen built still larger. This furnace has a double case, each 
 of which consists of fire-bricks. This case is enclosed by common bricks, and these by 
 a wall of stone masonry. The successive rows of bricks are laid stair-wise, having the 
 
 William Jessop, Esq., proprietor of the great iron works of Butterley and Codner 
 Park in Derbyshire, has invented a very elegant and effective apparatus for feeding his 
 blast furnaces with fuel, mine (calcined ironstone), and limestone in due proportions, 
 and equally distributed round the inside of the furnace. Figs. 132, 133. represent this 
 feed-apparatus. Fig. 132. shows at A, an outline of the furnace, and at B, the line of 
 entrance into its throat. C, is the feed mechanism. It consists of a long balance lever 
 barrow, D, E ; D, being an iron cylinder, open at top and bottom, 4 feet in diameter 
 and 2^ feet in height, in the inside of which a hollow cone of iron is suspended, with 
 its apex uppermost, so that while the base of the cone is kept above the level of the 
 bottom of the cylinder it shuts it ; but on the cone being lowered below that level, it 
 allows the charge of materials resting all round on the slant surface of the cone to fall 
 down equally round the side of the cylinder into the furnace. In fig. 133. the barrow 
 lever, D, E, is seen in profile or vertical section ; a, is the fulcrum wheel, upon which 
 the lever is in equilibrio when 9 cwt. of coals are put into the cylinder ; then a weight 
 is hung on, near the end, E, of the lever, as an equipoise either to 9 or 12 cwt. of mine, 
 according to circumstances ; and next, a weight to balance one-third of that weight of 
 limestone. These weights of materials being introduced into the cylinder, while the 
 barrow rests upon a level with the line E D, it is then rolled forward into its place, 
 as shown in the figure, upon the wheels, b b, upon a platform sustained on the top of an 
 
 F f 
 
218 SMELTING IRON FURNACES. 
 
 inverted cylinder within the cast-iron column, into which cylinder air is admitted 
 (through a valve opened by the workman) from the furnace blast, the air passing up the 
 
SMOKE PREVENTION. 
 
 219 
 
 which is 4 feet in diameter, without friction. The space, G H, fig. 133., is 36 feet 
 square. 
 
 The iron cone, which serves as a valve to the charging-drum or cylinder, is raised 
 and lowered by means of a chain passing round a worm-wheel, which is turned round 
 by an endless screw, acted upon by the long rod at c, which the workman can move by 
 hand at pleasure, thereby lowering or raising the end of the short lever, d, to which the 
 valve cone is suspended. The cord by which the workman opens or shuts the air 
 piston- valve is seen at e, f. I have viewed with much pleasure the precise and easy 
 movements of this feed -apparatus, at an excellent blast furnace in Codner Park iron 
 works. 
 
 SMOKE PREVENTION. Among the fifty several inventions which have been 
 patented for effecting this purpose, with regard to steam boiler and other large furnaces, 
 very few are sufficiently economical or effective. The first person who investigated this 
 subject in a truly philosophical manner was Mr. Charles Wye Williams, managing director 
 of the Dublin and Liverpool Steam Navigation Company, and he also has had the merit 
 of constructing many furnaces both for marine and land steam-engines, which thoroughly 
 prevent the production of smoke, with increased energy of combustion, and a more or 
 less considerable saving of fuel, according to the care of the stoker. The specific inven- 
 tion, for which he obtained a patent in 1840, consists in the introduction of a proper 
 quantity of atmospheric air to the bridges and flame-beds of the furnaces, through a 
 great number of small orifices, connected with a common pipe or canal, whose area can 
 be increased or diminished, according as the circumstances of complete combustion may 
 require, by means of an external valve. The operation of air thus entering in small 
 jets into the half-burned hydro-carburetted gases over the fires, and in the first flue, is 
 their perfect oxygenation, the development of all the heat which that can produce, and 
 the entire prevention of smoke. One of the many ingenious methods in which 
 Mr. Williams has carried out the principle of what he justly calls his Argand furnace, 
 is represented in Jiff. 134., where a is the ash-pit of a steam boiler furnace; b, is the 
 
 
 
 i 
 i 
 
 ' i 
 1 
 
 1 1 I 
 1 1 
 
 1 1 ' 1 
 
 , 1 r"r 
 
 1 1 1 1 1 1 
 I l l I I I 
 
 i 1 1 ; i 1 1 1 1 ; i 
 
 -OX 
 
 111,1 
 
 ' 
 
 'HI 
 
 a(( t> )) 
 
 i I I I- 
 
 1 
 i 
 
 
 a 
 
 
 mouth of a tube which admits the external air into the chamber or iron box of distri- 
 bution, c, placed immediately beyond the fire-bridge, g, and before the diffusion or 
 mixing chamber,/. The front of the box is perforated either with round or oblong 
 orifices, as shown in the two small figures e, e beneath fig. 134. ; d, is the fire-door, 
 which may have its fire-brick lining also perforated. In some cases, the fire-door pro- 
 jects in front, and it, as well as the sides and arched top of the fireplace, are constructed 
 of perforated fire-tiles, enclosed in common brickwork, with an intermediate space, into 
 which the air may be admitted in regulated quantity through a moveable valve in the 
 door. I have seen a fireplace of this latter construction performing admirably, without 
 smoke, with an economy of one-seventh of the coals formerly consumed in producing a 
 like amount of steam from an ordinary furnace ; h is the steam boiler. 
 
 Very ample evidence was presented last session to the Smoke Prevention Committee 
 of the House of Commons of the successful application of Mr. Williams's patent inven- 
 
 F f 2 
 
220 
 
 SODA. 
 
 tion to many furnaces of the largest dimensions, more especially by Mr. Henry Houlds- 
 worth, of Manchester, who, mounting in the first flue a pyrometrical rod, which acted 
 on an external dial index, succeeded in observing every variation of temperature, pro- 
 duced by varying the introduction of the air-jets into the mass of ignited gases passing 
 out of the furnace. He thereby demonstrated, that 20 per cent, more heat could be 
 easily obtained from the fuel, when Mr. Williams's plan was in operation, than when 
 the fire was left to burn in the usual way, and with the production of the usual 
 volumes of smoke. It is to be hoped, that a larw will be enacted in the next session of 
 parliament for the suppression, or at least abatement, of this nuisance, which so greatly 
 disfigures and pollutes many parts of London, as well as all our manufacturing towns, 
 while it acts injuriously on animal and vegetable life. Much praise is due to 
 Mr. Williams for his indefatigable and disinterested labours in this difficult enterprise, 
 and for his forbearance under much unmerited obloquy from narrow-minded prejudice 
 and indocile ignorance. 
 
 SOAP. Several contrivances upon this subject have bustled over the patent stage 
 within these few years ; such as Mr. Dunn's for making soap rapidly at a temperature 
 of 310° Fahr. under high steam pressure, by which many credulous shareholders were 
 gulled into a belief that they would realise by this joint-stock project 200,000/. per 
 annum. The soap so made was merely swelled in size and weight, by being sur- 
 charged with water, so that in a few weeks, the bars of it shrunk, rent, and twisted 
 into mere skeletons ; and being in this plight, returned to the company by their 
 customers, caused that large soap bubble to burst. 
 
 Mr. Sheridan's silica soap had a somewhat longer career, but is now also nearly 
 consigned to oblivion. Causticity and abrasiveness were the chief characteristics, 
 resulting from the mixture of a strong solution of silicate of soda, or liquor of flints, 
 with soap made in the common way. 
 
 The invention for which Dr. Normandy obtained a patent merits a better fate. 
 When yellow soap is made with the cheaper kinds of fat, it will hardly acquire a suffi- 
 cient degree or firmness or hardness to satisfy the thrifty washerwoman. It melts 
 away too rapidly in the hot water ; a defect which may be well remedied by the intro- 
 « duction into the soap of a little fused sulphate of soda ; and the salt concreting gives the 
 soap a desirable hardness, while it improves its colour, and renders it a more economical 
 article for the washing- tub. In a trial recently before the Court of Common Pleas, it 
 was proved that the soap made according to Dr. Normandy's patent was worth fully 
 21. a ton more than the original soap, without the sulphate of soda. 
 
 Mr. Dunn has recently obtained a patent for accelerating the process of soap-making ; 
 he promotes the combination of the alkali, fat, and water, by pumping streams of 
 atmospheric air through the saponaceous materials, while exposed to the usual heat in 
 the pan. This scheme is said to effect its purpose, and to save much time. 
 
 SODA. On the 30th of June, 1838, Messrs. Dyar and Hemmings obtained a 
 patent for manufacturing soda by the decomposition of sea salt with sesqui-carbonate or 
 bicarbonate of ammonia. Equal parts of the chloride of sodium and sesqui-carbonate 
 are prescribed, being very nearly the equivalent decomposing proportions, and the am- 
 monia salt is recommended to be added in powder to a saturated solution of the sea salt, 
 and the mixture to be stirred and then set aside till the mutual action and decomposition 
 be effected. Having been employed to examine this process for a gentleman who 
 wished to adopt it upon a manufacturing scale, I obtained the following results. On 
 making the prescribed mixture in the cold, brisk effervescence takes place, because 
 the quantity of carbonic acid combined with the ammonia is greater than the resulting 
 soda can readily absorb, even to form its bicarbonate, and this extrication of gas carries off 
 with it more or less ammonia, amounting, in carefully conducted experiments, to no 
 less than 27 per cent, of the sesqui-carbonate employed ; though the magma deposited 
 from the mixture was drained in vessels nearly close, and though the ammonia which 
 adhered to it, as well as that in the drained mother liquors, was recovered by distilla- 
 tion in vessels connected with a Woulfe's apparatus. Moreover, the utmost amount of 
 soda-ash (not pure carbonate) which was obtained, was only 37*5 for 100 of sea salt 
 used, whereas 90 of carbonate should result from 100 of the sea salt, with the above 
 equivalent dose of sesqui -carbonate of ammonia. This latter salt contains about one- 
 half more carbonic acid than is required by the soda to become a carbonate. A good 
 illustration of the loss of ammonia in a similar case is afforded by the decomposition of 
 chloride of calcium in solution, by adding to it the equivalent dose of pulverized 
 ammonia carbonate ; viz. 56 of the former and 59 of the latter. The rapid extrication 
 of the carbonic acid on making this mixture, causes such a waste of ammonia, that 
 more of the sesqui-carbonate must be afterwards introduced, to complete the decompo- 
 sition of the chloride ; the stronger the solution of the chloride the greater is the loss 
 of ammonia. 
 
SODA. 
 
 221 
 
 In one of my experiments, where were employed 3500 grains — half a pound avoir- 
 dupois, of each ingredient, the following were the products: — 
 
 Grains. 
 
 1. Ammonia recovered by distillation from the drained magma, 
 
 equivalent in sesqui-carbonate to - - - - 257 
 
 2. Ammonia as carbonate, from the remaining liquid, sucked into a 
 
 vacuous apparatus and distilled - 1509 
 
 3. Additional ammonia as carbonate, obtained from the cold mother 
 
 liquors, by distillation with quick lime, and out of the sal 
 ammoniac formed - - - - - 775 
 
 Sesqui carbonate employed 
 
 2541 
 - 3500 
 
 - 959 
 or 27*4 per cent. 
 
 The product from this experiment in dry soda ash was only 1500 grains, which were 
 
222 
 
 SPINNING. 
 
 found to contain only 1312 of pure carbonate, or 87*5 per cent, of the whole. Here is 
 a deficiency of soda carbonate, upon the quantity of the chloride used, of no less than 
 58^ per cent., for only 1312 grains are obtained instead of 3150. 
 
 Subsequently a method occurred to me, whereby this process, elegant in a scientific 
 point of view, might possibly be executed with advantage upon the commercial scale ; 
 but it would require a very peculiar apparatus, though not nearly so costly as what was 
 erected by Mr. Cooper under the direction of the patentees at Battersea, and in Brussels. 
 
 SODA WATER. At page 21. of vol. x. of the conjoined series of Newton's 
 Journal, the patent apparatus of Mr. F. C. Bakewell, of Hampstead, for making Soda 
 Water, is well described with illustrative figures. The patent was obtained in March 
 J 832, but how far it has been introduced into practice I have not heard. Its arrange- 
 ment discovers ingenuity, but it seems less likely to prove durable than the patent 
 apparatus of Mr. Tyler, which fig. 135. in the preceding page represents according to 
 his latest specification. A, is the gas generator, where the chalk and sulphuric acid are 
 mixed; B, the gasometer; C, the soda-water pump, for forcing in the gas; D, the con- 
 denser ; E, the solution (of soda) pan ; F, the bottling cork ; G, the acid bottle, at the 
 right hand shoulder of A ; H, the wheels, for working the agitator in the condenser ; 
 I, the pipe, for conveying the gas to the pump ; K, pipe for conveying the solution to the 
 pump ; L, cocks for regulating the admission of the gas into the solution ; M, dra wing-off 
 pipe leading to the bottling cork ; N, the forcing pipe from the pump to the condenser. 
 
 The vessel in which the soda water is condensed is lined with silver in order to 
 resist corrosion. 
 
 SOLDERING OF LEAD, and other metals, is called by its inventor M. de Riche- 
 mont, autogenous, because it takes place by the fusion of the two edges of the metals 
 themselves, without interposing another metallic alloy, as a bond of union. He effects 
 this purpose, by directing a jet of burning hydrogen gas, from a small movable beak, 
 upon the two surfaces or edges to be soldered together. Metals thus joined are much 
 less apt to crack asunder at the line of union, by differences of temperature, flexure, 
 &c, than when the common soldering processes are employed. The fusing together 
 the edges of lead sheets, for rrfaking sulphuric acid chambers, has been long practised 
 in this country, but it was performed by pouring some of the melted metal along the 
 line of junction, and afterwards removing its excess by means of a plumber's soldering 
 iron. The method of M. Richemont is a great improvement upon that old practice. 
 It is much quicker and more convenient. 
 
 SPINNING. The greatest improvement hitherto made in forming textile fabrics, 
 since the era of Arkwright, is due to Mr. G. Bodmer, of Manchester. By his patent 
 inventions the several organs of a spinning factory are united in one self-acting and 
 self-supplying body — a system most truly automatic. His most comprehensive patent 
 was obtained in 1824, and was prolonged by the Judicial Committee of the Privy 
 Council, for 7 years after the period of 14 years was expired. It contained the 
 first developement of a plan by which fibres of cotton, flax, &c. were lapped and 
 unlapped through all the operations of cleaning and blowing, carding, drawing, roving, 
 and spinning ; in the latter, however, only as far as the operation of feeding is con- 
 cerned. The lapping from the blower was then not new, but the lapping directly and 
 in connection with the carding engines was his invention, and was brought by him into 
 operation at St. Blaise in the Black Forest, several years before he took out his patent 
 
 Patent of 1835. 
 
 in England. The method applied through all the following operations was then 
 new. Mr. Dyer's and several other patents granted subsequently were decided and 
 
SPINNING 
 
 223 
 
 acknowledged infringements. The patent of 1824 was the beginning; the result of 
 which was the several patents for improvements in 1835, 1837, 1838, and 1842, of Mr. 
 Bodmer. 
 
 By a machine generally called a Devil or Opener ("Wolf," in German), which 
 consists of a feeding-plate set with teeth and a roller covered with spikes (see Jiff. 136.), 
 the cotton is cleared from its heaviest dirt and opened. This machine delivers the 
 cotton into a room or on to a travelling cloth, from which it is taken, weighed in 
 certain portions, and spread upon cloth in equal portions : this is then rolled up, and 
 placed behind the first blower. 
 
 The first blower has a feeding-plate like fig. 137., without teeth, and over this plate the 
 cotton is delivered to the operation of the common beaters, from which it is received 
 
 Patent of 1835. Patents of 1 824 and 1 8 35 . 
 
 into a narrow compartment of 4i or 5 inches broad, and wound, by means of his lap- 
 machines, upon rollers in beautifully level and well-cleaned laps. Eight of these 
 narrow laps are then placed behind a second blower, of a similar construction to the 
 first. Instead of the common beater, however, a drum with toothed straight edges is 
 used (see fig. 138. ), which opens the cotton still more, and separates the fibres from one 
 another. The cotton is again formed into similar narrow laps, which are still more 
 equal than the preceding ones, and eight of these laps are then placed behind the carding 
 engines. It was only by applying his lap-machine, patented in 1842, that he succeeded 
 in forming small laps on the blower ; without this he could not perform the doffing of 
 the laps without stopping the wire-cloth, and in doing this, an irregular lap would be 
 formed because of the accumulating of the falling cotton in one place while the wire- 
 cloth was standing. 
 
 Carding Engine. — His patent of 1 824 showed a mode of coupling a number of 
 carding engines, the product of which was delivered upon an endless belt or a trough, 
 and at the end of this trough was wound upon a roller. This arrangement wants no 
 description, as it is generally known. I have seen it in use on the Continent. 
 
 When a set of cards work together, any interruption or stoppage of a single carding 
 engine causes a defect in the produce of the whole lap. Interruptions occurred several 
 times a day by the stripping of the main cylinder, and during this operation the 
 missing band or sliver was supplied out of a can, being the produce of a single carding 
 engine working into cans (a spare card). The more objectionable defect was, however, 
 the difference of the product of the carding engine after the main cylinder had been 
 stripped ; the band or sliver from it will be thin and light until the cards of the main 
 cylinder are again sufficiently filled with cotton, when the band will again assume its 
 proper thickness. Another irregularity was caused by the stripping of the flats or top 
 cards, but was not so fatal as the first one. These defects were of course a serious 
 drawback in his system of working, the latter of which he provided against in his first 
 patent by stripping the top cards by mechanism ; the former, however, was only 
 conquered by his invention of the self-strippers for the main cylinders; thus the 
 carding engine may now work from Monday morning till Saturday night without 
 interruption, the cylinders requiring only to be brushed out every evening ; the con- 
 sequence is, that much time is gained, and a very equal, clean, and clear product is 
 obtained. Old carding engines to which he applied his feeders (see fig. 139.) and 
 main cylinder-clearers produce much superior work, and increase the production 
 from 18 to 24 per cent. 
 
 The main cylinder-clearer consists of a very light cast iron cylinder upon which 
 
224 SPINNING. 
 
 five, six, or more sets of wire brushes are fixed, which are caused to travel to and fro 
 across the main cylinder; the surface or periphery of the brushes overrunning the 
 surface or periphery of the main cylinder by 8 or 10 per cent., the brushes thus lifting 
 the cotton out of the teeth of the cards of the main cylinder, and causing the dirt and 
 lumps to fall. 
 
 As the brushes are not above a quarter-inch in breadth and travel to and fro, it is 
 clear that no irregularity can take place in the fleece which comes from the doffer ; 
 not more than l-40th part of the breadth of the cylinder being acted upon at the same 
 time. Figs. 140. and 141. give an idea of the clearer : the mechanism within the clearer 
 
 _J 
 
 Patents of 1 838 and 1 842. 
 
 and by which the brushes, a, are caused to travel is simple and solid. The main 
 cylinders for the carding engines are made of cast iron, the two sets of arms and rim 
 are cast in the same piece ; when complete, they weigh 50 lbs. less than those made of 
 wood. 
 
 The new lap machine connected with these engines is almost self-acting ; a girl has 
 only to turn a crank when the lap is full ; by this turn, the full lap is removed and an 
 empty roller put in its place, the band of cotton is cut, and no waste is made. 
 
 Drawing Frame. — The drawing frame of 1824 was improved, and the improvements 
 patented, in 1835, and others again in 1842. That of 1824 is known in Germany and 
 Fiance, and generally in use. The laps from the carding engine lap-machine are put 
 upon delivering rollers, behind a set of drawing rollers, and from them delivered upon a 
 belt or trough, and again formed into laps similar to those from the carding engines. 
 The next operation formed the laps into untwisted rovings, and the next again into 
 smaller untwisted rovings, or rovings with false twist in them, as infringed upon by 
 Dyer. The false twist was rather objectionable, and in his patent of 1835 he put a 
 number of rovings on the same bobbin, with left and right permanent twist in them. 
 This does very well; there is, however, a little objection to that place in which the 
 twist changes from right to left when it comes to the last operation before spinning. 
 In his patent of 1838, and particularly in that of 1842, he confined the left and right- 
 hand twist to the drawing frame, when he converts two laps into one roving, and forms a 
 roller or bobbin of 14 inches diameter and 15 inches broad, with six separate and twisted 
 rovings wound upon it. (See figs. 142. and 143.) The twist is given by tubes in two 
 directions, so that it remains in it (see fig. 143.), the tube turns in the same direction, 
 while the roving advances 4 or 5 inches, and then turns in the other direction. These 
 laps or bobbins are then placed behind a machine, which he calls a Coil-frame, the most 
 important arrangement of which he claimed already in his patent of 1835. It consists 
 of a slot with a travelling spout, without which the coils cannot be formed under 
 pressure. Coiling in cotton cannot be claimed, as it was done in the first system of 
 cotton spinning. 
 
 Coil Frame.^ — The bobbins (fig. 142.) are placed behind this machine, and two ends 
 from the bobbin are passed through the drawing rollers and formed into one untwisted 
 sliver or roving in the following manner : — When the cotton has passed through the 
 drawing rollers (see fig. 144.) and calender rollers, A, it is passed through the tube, B, 
 and the finger, C ; the spindle with its disc, D, revolves in such a proportion as to take 
 
SPINNING. 225 
 
 up the cotton which proceeds from the calender rollers, A, and cause the rovings to be 
 laid down in a spiral hne closely one by one, and as the rollers, A, work at a regular 
 
 142 
 
 143 
 
226 SPINNING. 
 
 slides up the spindle, G, made of tin-plate. The cotton enters through the slot, X, in 
 fig. D. It is quite evident that the finger, C, and spindle, G, only perform one and the 
 same varying motion, which is repeated at every fresh layer, and the coil is thus built 
 from below ; it is about 8 inches in diameter and 1 8 inches high when compressed, 
 and contains 4ilbs. of cotton. Mr. Bodmer has several modes of forming these coils, 
 but one only is shown here. These coils are placed behind the twist coil frames in half 
 cans or partly open ones or troughs, or behind a winding machine, where they are wound 
 upon rollers side by side, like the lap or bobbin shown in the drawing frame, and 
 placed behind the twist coil frame in this state. 
 
 Twist Coil Frame. — This frame forms rovings into coils similar to those above 
 explained, with this difference, that the rovings are fine, say, from 1 to 10 hanks per 
 pound, and regularly twisted : their diameter varies from 2i to 5 inches. The same 
 machine produces rovings more or less fine, but the diameter of the coils does not differ. 
 The difference of this machine from that above described consists in the dimensions of 
 their parts, and in its having the spindle, G, and the lid or top, F, revolving, as well as 
 the tube, B. (See fig. 145. ) In this machine the motion of the spindle, B, is uniform ; the 
 spindle, G, however, is connected by the bevel wheels, H and I, with a differential motion 
 at the end of the frame, with which the motion of the finger, C, corresponds. The skew 
 wheels, K and L, are connected with the drawing rollers, A. The speeds of the tube, B, 
 and the spindle, G, are so proportioned, that while the spindle, G, performs one revolution, 
 and therefore puts one twist into the roving, the tube, B, also performs one revolution, 
 missing so much as will be required to pass through the slot in the cap or disc, D, and 
 lay on it as much of the roving as proceeds from the rollers, A, and in which one twist 
 is contained. Of course the twist of these rovings can be adapted to their fineness and 
 varied ; but it is evident that, on account of the regularity of the machine and its sim- 
 plicity of movement, the rovings can never be stretched, and much less twist can be put 
 into them than can be put in the common fly frames. These coils are put behind the 
 spinning machines on shelves or in small cans, open in front ; or they are wound from 
 24 to 72 ends upon bobbins, and placed upon unlap rollers behind- the spinning 
 frames. 
 
 Coiling Machine for Carding Engines and Drawing Frames. — These are simple 
 machines, which may be applied to carding engines or drawing frames of any descrip- 
 tion. They form large coils, 9 inches in diameter and 22 inches long, when on the 
 machine. There are two spindles, a, (see fig. 146.) on each machine, for the purpose of 
 
 Patents of 1842. 
 
SPINNING. 
 
 227 
 
 doffing without stopping the drawing frame or carding engines. When one coil is 
 filled, the finger, b, is just brought over to the other spindle, so that the full coil is 
 stopped, and the new one begins to be formed without the slightest interruption of the 
 machine. 
 
 Mr. B. form coils in .various ways, also in cans ; but this description is sufficient to 
 show the application of this mode of winding up bands or rovings. Several of the above- 
 described machines are adopted with equal success to wool and flax. In his patents of 
 1835, 1837, and 1838, he shows several modes of applying his system to cotton and other 
 machinery. He winds directly from the carding engines the slivers separately upon long 
 bobbins, and he gives them twist in two directions, for the purpose of uniting the fibres 
 to some extent, so that they not only come off the bobbins without sticking to one 
 another, but also that they may draw smoother. He also showed a machine, by which 
 several rovings, say 4 or more, are put upon the same bobbin with conical ends ; 
 these bobbins are placed behind the mules or throstles, and are unwound by a belt or 
 strap running parallel with the fluted rollers of the spinning machine, as seen \nfig. 147. 
 The belt or band, A, is worked in a similar way to that described in his former patent, 
 and the bobbins, B, rest upon and revolve upon their surface, exactly according to the 
 speed of the belt. It is quite evident that the whole set of rovings must be unwound 
 exactly at the same speed, and that no stretching can take place. He can put real and 
 reversed twist in these rovings as well as false twist only. The most important feature 
 in the roving machine is a metal plate, in which a_ slot is formed through which the 
 rovings pass ; this slot is seen in figs. 148, 149, and 150. The cotton, when coming from 
 
 
 
 D 
 
 
 "1149 
 
 
 
 
 r 
 
 
 c c 
 
 
 fff . 
 
 150 
 
 tr; 
 
 5 
 
 Patent of 1835. 
 
 
 / 1 
 
 \ 
 
 
 
 1 
 
 
 \ 1 / 
 
 / 
 
 151 
 
 the drawing rollers, is passed through the twisters, C, and through the slot in the plate, D. 
 Thus he is enabled to put any convenient number of neatly formed and perfectly sepa- 
 rate coils upon the wooden barrel or bobbin. The bobbin formed upon these machines 
 is represented in fig. 151., and the conical ends are formed by a mechanism, by which 
 the twisters, C, are caused to approach a little more to one another, after each layer of 
 rovings has been coiled round the barrel : the section of the bobbin is therefore like 
 that shown in fig. 151. He makes use of exactly the same arrangement, viz. a finger 
 travelling along a slot in a plate, for the purpose of forming the coils, which has been 
 already described. 
 
 Rovings wound upon bobbins by means of tubes revolving in one direction, are cer- 
 tainly not so fit for spinning as rovings into which a small degree of twist is put. The 
 tube by which a twist is put in on one side and taken out at the other curls or ruffles 
 
 Gg 2 
 
228 
 
 SPINNING. 
 
 the cotton, and causes it to spread out as it passes between the rollers, while rovings 
 with a little permanent twist in them are held together in the process of drawing, and 
 thus produce smooth yarn. To remedy the evil above described, when untwisted rovings 
 are used, he causes the spouts or guides, through which the rovings pass into or between 
 the drawing rollers, to revolve slowly first in one, and then in the other direction, and 
 thus puts a certain quantity of twist into the rovings while they are being prepared for 
 spinning. Two modes of performing this operation are clearly described in his patent 
 of 1835. 
 
 There is a little defect in the working of the rovings with reversed twist when too 
 much or too little twist is put in them, or when the winding machine is not kept in good 
 order. This defect proceeds from the change in the twist of the roving seen at A, 
 fig. 152. ; in this place the twist is not like that at B, and it would, in some parts of the 
 
 152 
 
 A B 
 
 yarn, be detected under circumstances just described. In cases where double rovings 
 are used, the twisters are so arranged as to put the twist in the rovings, as shown in 
 fig. 153. : in this case the reversing place of one roving meets the twisted place of the 
 other, and the fault is completely rectified. 
 
 153 
 
 The preceding description gives an idea of Mr. Bodmer's admirable system of pre- 
 paring and spinning cotton, wool, flax, &c, and of the several processes; it would be 
 superfluous to describe the several machines, or the details of the same, as exhibited in 
 his patents. 
 
 In his patent of 1838, he specifies a self-actor, namely, a machine in itself, which 
 can be attached to 2, 3, or even 4 mules of almost any convenient number of 
 spindles. The mules are previously stripped of all their mechanism except the rollers 
 and their wheels, the carriage and spindles ; all the other movements ordinarily com- 
 bined with the mule are contained in the machine, which is placed between a set of 
 mules, as seen in fig. 154. ; a and 6, the self-actors, to each of which 3 mules are 
 
 yoked, and which are connected by 
 
 ]^ bands and shafts with the self- actor, 
 
 1 ' I or rather partly self -actor. A girl 
 
 I I of fifteen or sixteen years old stands 
 
 at x between a and b, and never 
 
 leaves her place except, perhaps, for 
 
 i 1 aiding in doffing or in banding the 
 
 1 - 1 spindles. The geering of the room 
 
 acts by means of straps upon the 
 machines a and b, and from these 
 i 1 machines all the movements are 
 
 \ | given to the six mules, namely, the 
 
 motion of the rollers, the spindles, 
 
 the drawing out of the carriage, the 
 
 [ a 1 * 1 b 1 after draft, &c. When the carriages 
 
 are to be put up, the girl takes 
 
 . hold of two levers of the machine a, 
 
 „ ! — * and by moving them in certain pro- 
 I I portions, acts upon two cones and 
 
 pulleys, and thus causes, in the most 
 easy and certain manner, the car- 
 I I riages to run in and the yarn to be 
 
 | | wound on the spindles. The first 
 
 -------------------------- machine Mr. B. made for this pur- 
 pose was completely self-acting, but 
 
 he found very soon that the me- 
 
 ' 1 chanism was more complicated and 
 
 1 | apt to go out of order than that of 
 
 the above- described machine; and 
 as it is necessary to have a girl of a certain age to watch over the piecers for a certain 
 number of mules, he preferred the simplified machine; placing the girl near these 
 machines, from whence the whole set of mules attached to the same can be overlooked ; 
 
SPINNING. 
 
 229 
 
 as the creels behind the mules are not wanted in his system, this impediment to the 
 sight of the girl would be removed. He schemed these machines for the purpose of 
 altering, at a trifling expense, the common mules into self-actors ; they are equally 
 good for any numbers of yarn. 
 
 Bastard Frame. — In his patent of 1838 and 1842, we find the description of a 
 very simple bastard frame, namely, a throstle with mule spindles, forming cops, as seen 
 in Jig. 155., and wound so hard that they can be handled about without any danger of 
 spoiling them ; in the same dimensions they contain one third 
 more yarn than the best cops of self-actors. The machine is 
 
 l^rrtr^ extremely simple; but owing to some circumstances in the 
 
 construction of the winders and plates, he has not been able 
 to spin advantageously upon large machines above No. 20's. 
 He has spun on it No. 56, and most beautiful yarn. The quantity this machinery 
 produces is nearly one third more than the best self-actor, on an equal number of 
 spindles, and the yarn and cops are much superior. Of course there is a copping 
 motion connected with the machine : the winding, however, is continuous, as well 
 
 155 
 
 4 
 
 Patents o/1838 and 1842. 
 
 as the twisting, and Jigs. 156. and 157. will give the reader an idea of the frame. 
 The yarn coming from the rollers, A, goes through an eye, B, to the wire, C, 
 fixed in the flyer, D, and from thence on to the mule spindle, E : as the spindle 
 revolves the flyer is dragged along, and by its centrifugal power winds the yarn tight 
 upon the spindles. 
 
230 SPIRITS. 
 SPIRITS. 
 
 Correspondence between Specific Gravity and Per Cents, over Proof at 60° F. 
 
 Specific 
 
 Per Cent. 
 
 Specific 
 
 Per Cent. 
 
 Specific 
 
 Per Cent. 
 
 Specific 
 
 Per Cent. 
 
 Gravity. 
 
 Over Proof. 
 
 Gravity. 
 
 Over Proof. 
 
 Gravity. 
 
 Over Proof. 
 
 Gravity. 
 
 Over Proof 
 _ 1 
 
 0-8156 
 
 67*0 
 
 •8455 
 
 SI *7 
 
 •8748 
 
 33-4 
 
 •9056 
 
 11-4 
 
 •8160 
 
 66-8 
 
 •8459 
 
 51-5 
 
 •8751 
 
 33-2 
 
 •9060 
 
 11-1 
 
 •8163 
 
 66-6 
 
 •8462 
 
 513 
 
 •8755 
 
 32-9 
 
 •9064 
 
 10-8 
 
 ■8167 
 
 66 - 5 
 
 •8465 
 
 51-1 
 
 •8758 
 
 32-7 
 
 •9067 
 
 10*6 
 
 •8170 
 
 66-3 
 
 •8469 
 
 50-9 
 
 •8762 
 
 32-4 
 
 •9071 
 
 10-3 
 
 •8174 
 
 66-1 
 
 •8472 
 
 50-7 
 
 •8765 
 
 32-2 
 
 •9075 
 
 10-0 
 
 •8178 
 
 65-6 
 
 •8476 
 
 50-5 
 
 •8769 
 
 320 
 
 •9079 
 
 9-7 
 
 •8181 
 
 65-8 
 
 •8480 
 
 503 
 
 •8772 
 
 31-7 
 
 •9082 
 
 9-4 
 
 •8185 
 
 65-6 
 
 •8482 
 
 50-1 
 
 •8776 
 
 315 
 
 •9085 
 
 9-2 
 
 •8188 
 
 65-5 
 
 •8486 
 
 49-9 
 
 •8779 
 
 31-2 
 
 •9089 
 
 8-9 
 
 •8192 
 
 65-3 
 
 •8490 
 
 49-7 
 
 •8783 
 
 31-0 
 
 •9093 
 
 8-6 
 
 •8196 
 
 65-1 
 
 •8493 
 
 49-5 
 
 •8786 
 
 30-8 
 
 •9697 
 
 8-3 
 
 •8199 
 
 65-0 
 
 •8496 
 
 49-3 
 
 •8790 
 
 30-5 
 
 •9100 
 
 8-0 
 
 •8203 
 
 64-8 
 
 •8499 
 
 49-1 
 
 •8793 
 
 30-3 
 
 •9104 
 
 7-7 
 
 •8206 
 
 64-7 
 
 •8503 
 
 48-9 
 
 •8797 
 
 30-0 
 
 •9107 
 
 7-4 
 
 ■8210 
 
 64-5 
 
 •8506 
 
 48-7 
 
 •8800 
 
 29-8 
 
 •9111 
 
 7'1 
 
 •8214 
 
 64-3 
 
 •8510 
 
 48-5 
 
 •8804 
 
 29-5 
 
 •9115 
 
 6-8 
 
 •8218 
 
 64-1 
 
 •8513 
 
 48-3 
 
 •8807 
 
 29-3 
 
 '9118 
 
 6-5 
 
 •8221 
 
 64-0 
 
 •8516 
 
 48-0 
 
 •8811 
 
 29*0 
 
 •9122 
 
 6-2 
 
 •8224 
 
 63-8 
 
 •8520 
 
 47-8 
 
 •8814 
 
 28 8 
 
 •9126 
 
 5-9 
 
 •8227 
 
 63-6 
 
 •8523 
 
 47-6 
 
 •8818 
 
 28-5 
 
 •9130 
 
 5-6 
 
 •8231 
 
 63-4 
 
 •8527 
 
 47-4 
 
 •8822 
 
 28-3 
 
 •9134 
 
 53 
 
 •8234 
 
 63-2 
 
 •8530 
 
 47-2 
 
 •8825 
 
 28-0 
 
 •9137 
 
 5-0 
 
 •8238 
 
 63-1 
 
 •8533 
 
 47-0 
 
 •8829 
 
 27'8 
 
 •9141 
 
 4-8 
 
 •8242 
 
 62-9 
 
 •8537 
 
 46-8 
 
 •8832 
 
 27-5 
 
 •9145 
 
 4-5 
 
 •8245 
 
 62-7 
 
 •8540 
 
 46-6 
 
 •8836 
 
 27-3 
 
 •9148 
 
 4-2 
 
 •8249 
 
 62-5 
 
 •8543 
 
 46-4 
 
 •8840 
 
 27-0 
 
 •9152 
 
 3-9 
 
 •8252 
 
 62-3 
 
 •8547 
 
 46-2 
 
 •8843 
 
 26-8 
 
 •9156 
 
 3-6 
 
 •8256 
 
 622 
 
 •8550 
 
 46-0 
 
 •8847 
 
 26-5 
 
 •9159 
 
 33 
 
 •8259 
 
 620 
 
 •8553 
 
 45-8 
 
 •8850 
 
 26-3 
 
 •9163 
 
 3-0 
 
 •8263 
 
 61-8 
 
 •8556 
 
 45-6 
 
 •8854 
 
 26-0 
 
 •9167 
 
 2-7 
 
 •8266 
 
 61-6 
 
 •8560 
 
 45-4 
 
 •8858 
 
 25-8 
 
 •9170 
 
 2-4 
 
 •8270 
 
 61-4 
 
 •8563 
 
 45-2 
 
 •8861 
 
 25-5 
 
 •9174 
 
 21 
 
 •8273 
 
 61-3 
 
 •8566 
 
 45-0 
 
 •8865 
 
 25-3 
 
 •9178 
 
 1-9 
 
 •8277 
 
 61-1 
 
 •8570 
 
 44-8 
 
 •8869 
 
 25-0 
 
 •9182 
 
 16 
 
 •8280 
 
 609 
 
 •8573 
 
 44-6 
 
 •8872 
 
 24-8 
 
 •9185 
 
 1-3 
 
 •8284 
 
 60-7 
 
 •8577 
 
 44-4 
 
 •8876 
 
 24*5 
 
 •9189 
 
 1-0 
 
 •8287 
 
 60-5 
 
 •8581 
 
 44-2 
 
 •8879 
 
 24-3 
 
 •9192 
 
 0-7 
 
 •8291 
 
 60-4 
 
 •8583 
 
 43-9 
 
 •8883 
 
 240 
 
 •9196 
 
 0-3 
 
 •8294 
 
 60-2 
 
 •8587 
 
 43-7 
 
 •8886 
 
 23-8 
 
 •9200 
 
 Proof. 
 
 •8298 
 
 60-0 
 
 •8590 
 
 43-5 
 
 •8890 
 
 23-5 
 
 Under 
 
 Proof. 
 
 •8301 
 
 59-8 
 
 •8594 
 
 433 
 
 •8894 
 
 23-2 
 
 •9204 
 
 0-3 
 
 •8305 
 
 59-6 
 
 •8597 
 
 43-1 
 
 •8897 
 
 23-0 
 
 •9207 
 
 0-6 
 
 •8308 
 
 59-5 
 
 •8601 
 
 42-8 
 
 •8901 
 
 22-7 
 
 •9210 
 
 0-9 
 
 •8312 
 
 59-3 
 
 •6604 
 
 42-6 
 
 •8904 
 
 22-5 
 
 •9214 
 
 13 
 
 •8315 
 
 59-1 
 
 •8608 
 
 42-4 
 
 •8908 
 
 22-2 
 
 •9218 
 
 1-6 
 
 •8319 
 
 58-9 
 
 •8611 
 
 42-2 
 
 •8912 
 
 21-9 
 
 •9222 
 
 
 •8322 
 
 58-7 
 
 •8615 
 
 42-0 
 
 •8915 
 
 21-7* 
 
 •9226 
 
 2-2 
 
 •8326 
 
 58-6 
 
 •8618 
 
 41-7 
 
 •8919 
 
 21-4 
 
 •9229 
 
 2-5 
 
 •8329 
 
 58-4 
 
 •8622 
 
 41-5 
 
 •8922 
 
 21-2 
 
 •9233 
 
 2-8 
 
 •8333 
 
 58-2 
 
 •8625 
 
 41-3 
 
 •8926 
 
 20-9 
 
 •9237 
 
 3-1 
 
 •8336 
 
 58-0 
 
 •8629 
 
 411 
 
 •8930 
 
 20-6 
 
 •9241 
 
 34 
 
 •8340 
 
 57*8 
 
 •8632 
 
 40-9 
 
 •8933 
 
 20-4 
 
 •9244 
 
 37 
 
 •8344 
 
 577 
 
 •8636 
 
 40*6 
 
 •8937 
 
 20-1 
 
 •9248 
 
 4-0 
 
 •8347 
 
 575 
 
 •8639 
 
 40-4 
 
 •8940 
 
 19-9 
 
 •9252 
 
 4-4 
 
 •8351 
 
 57-3 
 
 •8643 
 
 40-2 
 
 •8944 
 
 19-6 
 
 •9255 
 
 4-7 
 
 •8354 
 
 57-1 
 
 •8646 
 
 40-0 
 
 •8948 
 
 19-3 
 
 •9259 
 
 5-0 
 
 •8358 
 
 56-9 
 
 •8650 
 
 39-8 
 
 •8951 
 
 191 
 
 •9263 
 
 5-3 
 
 •8362 
 
 56-8 
 
 •8653 
 
 39-5 
 
 •8955 
 
 18-8 
 
 •9267 
 
 5-7 
 
 •8365 
 
 56-6 
 
 •8657 
 
 393 
 
 •8959 
 
 18-6 
 
 •9270 
 
 6-0 
 
 •8369 
 
 56-4 
 
 •8660 
 
 39-1 
 
 •8962 
 
 18-3 
 
 •9274 
 
 6-4 
 
 •8372 
 
 56-2 
 
 •8664 
 
 38-9 
 
 •8966 
 
 18-0 
 
 •9278 
 
 6-7 
 
 •8376 
 
 56-0 
 
 •8667 
 
 38-7 
 
 •8970 
 
 17-7 
 
 •9282 
 
 7-0 
 
 •8379 
 
 55-9 
 
 •8671 
 
 38-4 
 
 •8974 
 
 17-5 
 
 •9286 
 
 7'3 
 
 •8383 
 
 55-7 
 
 •8674 
 
 38-2 
 
 •8977 
 
 17-2 
 
 •9291 
 
 7-7 
 
 •8386 
 
 55-5 
 
 •8678 
 
 38-0 
 
 •8981 
 
 16-9 
 
 •9295 
 
 8-0 
 
 •8390 
 
 55-3 
 
 •8681 
 
 37-8 
 
 •8985 
 
 16-6 
 
 •9299 
 
 83 
 
 •8393 
 
 55-1 
 
 •8685 
 
 37-6 
 
 •8989 
 
 164 
 
 •9302 
 
 8-6 
 
 •8396 
 
 55-0 
 
 •8688 
 
 37-3 
 
 •8992 
 
 16-1 
 
 •9306 
 
 9-0 
 
 •8400 
 
 54-8 
 
 •8692 
 
 37-1 
 
 •8996 
 
 15-9 
 
 •9310 
 
 9-3 
 
 •8403 
 
 54-6 
 
 •8695 
 
 36-9 
 
 •9000 
 
 15-6 
 
 •9314 
 
 9-7 
 
 •8407 
 
 54-4 
 
 •8699 
 
 36-7 
 
 •9004 
 
 15-3 
 
 •9318 
 
 10-0 
 
 •8410 
 
 54-2 
 
 •8702 
 
 36-4 
 
 •9008 
 
 15-0 
 
 •9322 
 
 10-3 
 
 "8413 
 
 54" 1 
 
 •8706 
 
 36' 2 
 
 •901 1 
 
 14-8 
 
 •9326 
 
 10*7 
 
 •8417 
 
 53-9 
 
 •8709 
 
 35-9 
 
 •9015 
 
 14-5 
 
 •9329 
 
 11-0 
 
 •8420 
 
 53-7 
 
 •8713 
 
 35-7 
 
 •9019 
 
 14-2 
 
 •9332 
 
 11-4 
 
 •8424 
 
 53-5 
 
 •8716 
 
 35-5 
 
 •9023 
 
 139 
 
 •9337 
 
 11-7 
 
 •8427 
 
 533 
 
 •8720 
 
 352 
 
 •9026 
 
 13-6 
 
 •9341 
 
 121 
 
 •8431 
 
 53-1 
 
 •8723 
 
 35-0 
 
 •9030 
 
 13-4 
 
 •9345 
 
 124 
 
 •8434 
 
 52-9 
 
 •8727 
 
 347 
 
 •9034 
 
 131 
 
 •9349 
 
 12-8 
 
 •8438 
 
 52-7 
 
 •8730 
 
 345 
 
 •9038 
 
 12-8 
 
 •9353 
 
 131 
 
 •8441 
 
 52-5 
 
 •8734 
 
 34-3 
 
 •9041 
 
 12-5 
 
 •9357 
 
 135 
 
 •8445 
 
 52-3 
 
 •8737 
 
 34-1 
 
 •9045 
 
 12-2 
 
 •9360 
 
 139 
 
 •8448 
 
 52-1 
 
 •8741 
 
 33-8 
 
 •9049 
 
 12-0 
 
 •9364 
 
 142 
 
 •8452 
 
 5J-9 
 
 •8744 
 
 336 
 
 •9052 
 
 11-7 
 
 •9368 
 
 14-6 j 
 
STAINED GLASS. 231 
 
 Table — continued. 
 
 Specific 
 Gravity. 
 
 Per Cent. 
 Under, Prf. 
 
 Specific 
 Gravity. 
 
 Per Cent. 
 Under Prf. 
 
 Specific 
 Gravity. 
 
 Per Cent. 
 Under Prf. 
 
 Specific 
 Gravity. 
 
 Per Cent. 
 Under Prf. 
 
 '9372 
 
 14 - 9 
 
 •9530 
 
 31-0 
 
 •9685 
 
 52-2 
 
 •9846 
 
 79-2 
 
 •9376 
 '9380 
 
 15 - 3 
 
 •9534 
 
 31-4 
 
 •9689 
 
 52-9 
 
 •9850 
 
 79-8 
 
 15'7 
 
 •9539 
 
 31i 
 
 •9693 
 
 533 
 
 •9854 
 
 80-4 
 
 •9384 
 "9388 
 
 16'0 
 
 •9542 
 
 32*3 
 
 •9697 
 
 54-2 
 
 •9858 
 
 81-1 
 
 164 
 
 •9546 
 
 32-8 
 
 •9701 
 
 54-8 
 
 •9862 
 
 817 
 
 •9392 
 
 167 
 
 '9550 
 
 33-2. 
 
 •9705 
 
 555 
 
 •9866 
 
 82-3 
 
 •9396 
 
 17'1 
 
 '9553 
 
 337 
 
 •9709 
 
 56-2 
 
 •9870 
 
 82-9 
 
 •9399 
 •9403 
 
 17*5 
 
 ■9557 
 
 342 
 
 •9713 
 
 56-9 
 
 •9874 
 
 83-5 
 
 178 
 
 '9561 
 
 34-6 
 
 •9718 
 
 57-6 
 
 •9878 
 
 84-0 
 
 •94,07 
 
 18'2 
 
 •9565 
 
 35- 1 
 
 •9722 
 
 58 3 
 
 •9882 
 
 84-6 
 
 "941 1 
 
 18*5 
 
 •9569 
 
 356 
 
 •9726 
 
 59-0 
 
 •9886 
 
 85-2 
 
 '9415 
 
 18'9 
 
 •9573 
 
 36- 1 
 
 •9730 
 
 597 
 
 •9890 
 
 85-8 
 
 "9419 
 
 19'3 
 
 •9577 
 
 36-6 
 
 •9734 
 
 60-4 
 
 •9894 
 
 86-3 
 
 •9422 
 
 19"7 
 
 •958O 
 
 37-1 
 
 •9738 
 
 61-1 
 
 •9898 
 
 86-9 
 
 '9426 
 •9430 
 
 20'0 
 
 •9584 
 
 376 
 
 •9742 
 
 61-8 
 
 •9902 
 
 87-4 
 
 20'4 
 
 •9588 
 
 38-1 
 
 •9746 
 
 625 
 
 •9906 
 
 88-0 
 
 "9434 
 
 20"8 
 
 '9592 
 
 38' 6 
 
 •9750 
 
 63-2 
 
 •9910 
 
 88-5 
 
 *9437 
 
 21 -2 
 
 •9596 
 
 39-1 
 
 •9754 
 
 639 
 
 •9914 
 
 89-1 
 89-6 
 
 "9441 
 
 21'6 
 
 •9599 
 
 39- 6 
 
 •9758 
 
 64-6 
 
 •9918 
 
 '9445 
 
 21'9 
 
 •9603 
 
 40 4 1 
 
 •9762 
 
 65-3 
 
 •9922 
 
 90-2 
 
 •9448 
 
 22'2 
 
 •9607 
 
 40-6 
 
 •9766 
 
 66-0 
 
 •9926 
 
 907 
 
 '9452 
 
 22 - 7 
 
 •96H 
 
 41*1 
 
 •9770 
 
 667 
 
 •9930 
 
 91-2 
 
 •9456 
 '9460 
 
 23' 1 
 
 •9615 
 
 417 
 
 •9774 
 
 67-4 
 
 •9934 
 
 917 
 
 23'5 
 
 •9619 
 
 422 
 
 •9778 
 
 68-0 
 
 •9938 
 
 92-3 
 
 •9464 
 •9468 
 
 23' 9 
 
 •9623 
 
 42-8 
 
 •9782 
 
 687 
 
 •9942 
 
 92-8 
 
 24' 3 
 
 •9627 
 
 433 
 
 •9786 
 
 69-4 
 
 •9946 
 
 933 
 
 •9472 
 
 24'7 
 
 •9631 
 
 43-9 
 
 •9790 
 
 70- J 
 
 •9950 
 
 93-8 
 
 '9476 
 
 25' 1 
 
 •9635 
 
 44-4 
 
 •9794 
 
 70-8 
 
 •9954 
 
 94 3 
 
 •9480 
 
 25 '5 
 
 •9638 
 
 45-0 
 
 •9798 
 
 7P4 
 
 •9958 
 
 949 
 
 •9434 
 •9488 
 
 25*9 
 
 •9642 
 
 45-5 
 
 •9802 
 
 72-1 
 
 •9962 
 
 94-4 
 
 26'3 
 
 •9646 
 
 46-1 
 
 •9806 
 
 72-8 
 
 •9966 
 
 95-9 
 
 •9492 
 •9496 
 
 26'7 
 
 •9G50 
 
 467 
 
 •9810 
 
 73-5 
 
 •9970 
 
 96-4 
 
 271 
 
 •9654 
 
 473 
 
 •9814 
 
 74-1 
 
 •9974 
 
 96-8 
 
 •9499 
 
 27'5 
 
 •9657 
 
 479 
 
 •9816 
 
 74-8 
 
 •9978 
 
 97 3 
 
 •9503 
 
 28'0 
 
 •9661 
 
 48-5 
 
 •9822 
 
 75-4 
 
 •9982 
 
 977 
 
 •9507 
 
 28'4 
 
 •9665 
 
 49- 1 
 
 •9826 
 
 76-1 
 
 •9986 
 
 98-2 
 
 •9511 
 
 28-8 
 
 •9669 
 
 497 
 
 •9830 
 
 767 
 
 •9990 
 
 987 
 
 •9515 
 
 29'2 
 
 •9674 
 
 50-3 
 
 •9834 
 
 773 
 
 •9993 
 
 99-1 
 
 •9519 
 
 297" 
 
 •9677 
 
 51-0 
 
 •9838 
 
 78-0 
 
 •9997 
 
 996 
 
 •9522 
 
 30'1 
 
 •9681 
 
 516 
 
 •9842 
 
 786 
 
 1-0000 
 
 100-0 
 
 •9526 
 
 30-6 
 
 
 
 
 
 
 
 STAINED GLASS. The blues of vitrified colours are all obtained from the oxide 
 of cobalt. Cobalt ore (sulphuret) being well roasted at a dull red heat, to dissipate 
 all the sulphur and arsenic, is dissolved in somewhat dilute nitric acid, and after the 
 addition of much water to the saturated solution, the oxide is precipitated by carbonate 
 of soda, then washed upon a filter and dried. The powder is to be mixed with thrice 
 its weight of saltpetre ; the mixture is to be deflagrated in a crucible, by applying a red 
 hot cinder to it, then exposed to the heat of ignition, washed and dried. Three parts 
 of this oxide are to be mixed with a flux, consisting of white sand, borax, nitre, and a 
 little chalk, subjected to fusion for an hour, and then ground down into an enamel 
 powder for vise. Blues of any shade or intensity may be obtained from the above, by 
 mixing it with more or less flux. 
 
 The beautiful greenish-yellow, of which colour so many ornamental glass vessels have 
 been lately imported from Germany, is made in Bohemia by the following process. Ore 
 of uranium, Uran-ochre, or Uran-glimmer, in fine powder, being roasted and dissolved in 
 nitric acid ; the filtered solution is to be freed from any lead present in it, by the cautious 
 addition of dilute sulphuric acid. The clear green solution is to be evaporated to dry- 
 ness, and the mass ignited till it becomes yellow. One part of this oxide is to be mixed 
 with 3 or more parts of a flux, consisting of 4 parts of red lead and 1 of ground flints ; 
 the whole fused together and then reduced to powder. 
 
 Chrome Green. Triturate together in a mortar equal parts of chromate of potash and 
 flowers of sulphur : put the mixture into a crucible and fuse. Pour out the fluid mass; 
 when cool, grind and wash well with water to remove the sulphuret of potash and to 
 leave the beautiful green oxide of chrome. This is to be collected upon a filter, dried, 
 rubbed down along with thrice its weight of a flux, consisting of 4 parts of red lead and 1 
 part of ground flints fused into a transparent glass; the whole is now to be melted and 
 afterwards reduced to a fine powder. 
 
 Violet. One part of calcined black oxide of manganese, one of zaffre, ten parts of 
 white glass pounded, and one of red lead, mixed, fused, and ground. Or gold purple 
 (Cassius's purple precipitate) with chlorsilver previously fused, with ten times its weight 
 of a flux, consisting of ground quartz, borax, and red lead, all melted together ; or, 
 solution of tin being dropped into a large quantity of water, solution of nitrate of silver 
 may be first added, and then solution of gold in aqua regia, in proper proportions. The 
 precipitate to be mixed with flux and fused. 
 
232 
 
 STARCH. 
 
 STARCH. In January 1839, M. Pierre Isidore Verdure obtained a patent for 
 making starch, the chief object of which was to obtain the gluten of the wheat in a pure 
 state, as a suitable ingredient in making bread, biscuits, &c. He works wheat flour 
 into dough by a machine, kneads it, washes out the starch by streams of cold water, 
 a process long known to the chemist, and purifies the starch by fermentation of the 
 superjacent water. I can see nothing new in his specification. 
 
 Mr. Jones's patent, of date April 1840, is based upon the purification of the starch 
 of rice and other farinaceous matters, by means of caustic alkali. He macerates 100 
 lbs. of ground rice in 100 gallons of a solution composed of 200 grains of caustic soda 
 or potash to a gallon of water, stirs it gradually, till the whole be well mixed ; after 24 
 hours, draws ofF the superjacent liquid solution of gluten in alkali, treats the starchy 
 deposit with a fresh quantity of weak caustic lye, and thus repeatedly, till the starch 
 becomes white and pure. The rice before being ground is steeped for some time in a 
 like caustic lye, drained, dried, and sent to the mill. 
 
 Starch is made from wheat flour in a like way. The gluten may be recovered for 
 use, by saturating the alkaline solution with sulphuric acid, washing and drying the pre- 
 cipitate. 
 
 In June 1841, Mr. W. T. Berger obtained a patent for manufacturing starch by the 
 agency of an alkaline salt upon rice. He prefers the carbonates of potash and soda. 
 
 Mr. James Colman, by his patent invention of December 1841, makes starch from 
 ground maize or Indian corn, by the agency either of the ordinary process of steeping 
 and fermenting, or of caustic or carbonated alkaline lyes. He also proposes to em- 
 ploy dilute muriatic acid to purify the starchy matter from gluten, &c. — See Newton's 
 Journal, C. S. xix. 246. ; xx. 184. 188. ; and xxi. 173. 
 
 The manufacture of potato flour ( fecule) or starch in France and Holland has been 
 economised to such a degree that they supply this country with it, at the rate of 8s. or 
 10s. a hundredweight. Fig. 158. represents in section the powerful and ingenious 
 
 mechanical grater, or rasp (rape), now used in France, a a, is the canal, or spout, 
 along which the previously well-washed potatoes descend ; b b, is the grater, composed 
 of a wooden cylinder, on whose round surface circular saw rings of steel, with short 
 sharp teeth, are planted pretty close together. The greater the velocity of the 
 cylinder the finer is the pulp. A cylinder 20 inches in diameter revolves at the rate of 
 from 600 to 900 times in a minute, and it will convert into pulp from 14 to 15 hecto- 
 
STEARINE. 
 
 233 
 
 litres (about 300 imperial gallons) of potatoes in an hour. Potatoes contain from 15 
 to 22 per cent, of dry fecula. The pulp, after leaving the rasp, passes directly into the 
 apparatus for the preparation of the starch, c c, is a wooden hopper for receiving the 
 falling pulp, with a trap door, d, at bottom. E, is the cylinder-sieve of M. Etienne ; 
 f, a pipe ending in a rose spout, which delivers the water requisite for washing the pulp, 
 and extracting the starch from it ; g g, a diaphragm of wire cloth, with small meshes, 
 on which the pulp is exposed to the action of the brushes i i, moving with great speed, 
 whereby it gives out its starchy matter, which is thrown out by a side aperture into the 
 spout n. The fecula now falls upon a second web of fine wire-cloth, and leaves upon it 
 merely some fragments of the parenchyma or cellular matter of the potato, to be turned 
 out by a side opening in the spout n. The sifting or straining of the starch likewise 
 takes place through the sides of the cylinder, which consist also of wire-cloth ; it is 
 collected into a wooden spout, m, and is thence conducted into the tubes o o, to be de- 
 posited and washed, p, is a metre-toothed wheel-work placed on the driving-shaft, and 
 gives motion to the upright axis or spindle, q q, which turns the brushes, i i. 
 
 STEA11INE. Fig. 159. is a view of both the exterior and interior of the saponi- 
 
 fying tun of a stearine factory ; where the constituents of the tallow are combined with 
 quicklime, by the intervention of water and steam : a, is the upright shaft of iron, 
 turned by the bevel wheel above, in gear with another bevel wheel on the moving 
 shaft, not shown in this figure. This upright shaft bears several arms d, furnished 
 with large teeth. The tun is bound with strong hoops of iron, and its contents are 
 heated by means of a spiral tube laid on the bottom, perforated with numerous holes, 
 and connected by a pipe with a high-pressure steam-boiler. 
 
 Fig. 160. represents a longitudinal section of the horizontal hydraulic press for 
 depriving stearic acid, as also spermaceti, of all their fluid oily impurities, a, is the 
 
 cylinder of the press ; b, the ram or piston ; i, i, i, i, hair and flannel bags inclosing 
 the impure cakes to be exposed to pressure ; d, d, d, d, iron plates previously heated, 
 and placed between every two cakes to facilitate the discharge of their oily matter ; e, e, 
 
 Hh 
 
234 
 
 STEEL. 
 
 solid iron end of the press, made to resist great pressure ; it is strongly bolted to the 
 cylinder a, so as to resist the force of the ram ; g, g, iron rods, for bringing back the 
 ram b, into its place after the pressure is over, by means of counter weights suspended 
 to a chain, which passes over the pulleys h, h ; i, i, a spout and a sheet-iron pan for re- 
 ceiving the oily fluid. 
 
 STEEL. One of the greatest improvements which this valuable modification of 
 iron has ever received is due to Mr. Josiah M. Heath, who, after many elaborate and 
 costly researches, upon both the small and the great scale, discovered that by the 
 introduction of a small portion, 1 per cent., and even less, of carburet of manganese 
 into the melting-pot along with the usual broken bars of blistered steel, a cast steel was 
 obtained, after fusion, of a quality very superior to what the bar steel would have 
 yielded without the manganese, and moreover possessed of the new and peculiar pro- 
 perty of being weldable either to itself or to wrought iron. He also found that a 
 common bar-steel, made from an inferior mark or quality of Swedish or Russian iron, 
 
 would, when so treated, produce 
 an excellent cast steel. One im- 
 mediate consequence of this dis- 
 covery has been the reduction of 
 the price of good steel in the 
 Sheffield market by from 30 to 40 
 per cent., and likewise the manu- 
 facture of table-knives of cast 
 steel with iron tangs welded to 
 them ; whereas, till Mr. Heath's 
 invention, table-knives were ne- 
 cessarily made of shear steel, with 
 unseemly wavy lines in them, 
 because cast steel could not be 
 welded to the tangs. Mr. Heath 
 obtained a patent for this and 
 other kindred meritorious inven- 
 tions on the 5th of April 1839; 
 but, strange and melancholy to 
 say, he has never derived any 
 thing from his acknowledged im- 
 provement but vexation and loss, 
 in consequence of a numerous 
 body of Sheffield steel manufac- 
 turers having banded together to 
 pirate his patent, and to baffle 
 him in our complex law courts. 
 I hope, however, that eventually 
 justice will have its own, and the 
 ridiculously unfounded pretences 
 of the pirates to the prior use of 
 carburet of manganese will be set 
 finally at rest. It is supposed 
 that fifty persons at least are em- 
 barked in this pilfering conspiracy. 
 
 The furnace of cementation in 
 which bar-iron is converted into 
 bar or blistered steel is represented 
 in Jigs. 161, 162, 163. It is rect- 
 angular and covered in by a 
 groined or cloister arch : it con- 
 tains two cementing chests, or 
 sarcophaguses, c, c, made either 
 of fire-stone or Hre-bricks: each 
 is 2± feet wide, 3 feet deep, and 
 1 2 long ; the one being placed on 
 the one side, and the other on the 
 other of the grate, a b, which 
 occupies the whole length of the 
 furnace, and is from 13 to 1 4 feet 
 long. The grate is 14 inches 
 broad, and rests from 10 to 12 inches below the inferior plane or bottom level of the 
 chests ; th<- height of the top of the arch above the chests is 5± feet ; the bottom of the 
 
STILL. 
 
 235 
 
 chests is nearly on a level with the ground, so that the bars do not need to be lifted 
 high in charging the furnace. The flame rises between the two chests, passes also 
 below and round them through horizontal and vertical flues, d, and issues from the 
 furnace by an opening, h, in the top of the vault, and by orifices, t, which communicate 
 with the chimneys placed in the angles. The whole is placed within a large cone of 
 bricks, 25 or 30 feet high, and open at top : this cone increases the draught, makes it 
 more regular, and carries off the smoke away from the establishment. The furnace 
 has three doors ; two, t {fig. 162.), above the chests, serve to admit and to remove the 
 bars ; .they are about 7 or 8 inches square : in each of them a piece of sheet-iron is put, 
 folded back on its edges ; upon which the bars are made to slide, so as to save the 
 wall. A workman enters by the middle door, p, to arrange the bars ; the trial bars 
 are taken out from time to tttne by the apertures, s, (fig. 161.) left in the sides of the 
 chests. The bars are laid in strata, along with wood charcoal in powder, in the said 
 chests ; they are about 3 inches broad, and one-third of an inch thick ; they must 
 not be placed too near each other, lest they should get welded together ; the last or 
 uppermost layer is covered with a stratum of loamy matter from 4 to 5 inches thick. 
 The furnace must be gradually heated, not reaching its maximum temperature before 
 8 or 9 days, and the cooling lasts 5 or 6 days ; the whole operation 1 8 or 20 days, 
 and sometimes more, according to the quality of the steel to be cemented. About 
 13 tons of coals are consumed in this period. It is of consequence that the refrigeration 
 be slow, to favour the crystallisation of the metal. The grain of the steel varies with 
 the rate of cooling, the largest and whitest grain denoting the most fusible steel. 
 
 STILL. The continuous system of distillation has been carried in France to a great 
 pitch of perfection, by the ingenuity chiefly of M. Cellier Blumenthal, and M. Ch. 
 Derosne. Fig. 164. is a general view of their apparatus ; a and b are boilers or alembics 
 
 encased in brickwork, and re- 
 ceiving directly the action of 
 the flame playing beneath 
 them; in the copper, a, the 
 vinasse, or spent wine, is finally 
 exhausted of all its alcohol, 
 c is the column of distillation ; 
 D, the column of rectification ; 
 
 e, the wine-heating condenser ; 
 
 f. the refrigerator ; g, a vessel 
 supplying vinasse to the cooler 
 f, and feeding itself at the same 
 time by means of a ball stop- 
 cock placed in the vessel h ; 
 h, reservoir of vinasse ; i, tube 
 of communication conducting 
 the alcoholic vapours of the 
 rectifying column, d, up into 
 the flat worm of the wine- 
 heater, e ; a, stop-cock of dis- 
 charge of the alembic, a ; when 
 the operation goes on, the 
 spent vinasse runs off con- 
 tinually by this stop-cock ; 
 b, a glass tube to show the 
 height of the liquor in a ; c, a 
 safety-valve ; d, a stop-cock 
 for passing the vinasse from 
 the alembic, b, into the bottom 
 of the alembic, a ; e, a tube 
 to lead the alcoholic vapours, 
 generated in a, into the bottom 
 of b, which vapours, in passing 
 through the liquor in b, heat it, 
 and are partially condensed ; 
 f, glass tube to mark the level 
 of the liquor in b ; g, and g, level 
 indicators ; h, pipe conducting 
 
 the vinasse from the lower part of the wine-heater, e, upon the uppermost of the series 
 of horizontal discs, mounted within the column of distillation ; i, a stop-cock for empty- 
 ing the wine-heater at the end of an operation ; /, I, two tubes fitted to the wine-heater, 
 e, of which the first descends into the last compartment of the rectifier, whence it rises 
 
 H h 2 
 
236 
 
 STILL. 
 
 to the fifth ; and the second tube descends to the third compartment, whence it rises above 
 the second. At the curvature of each of these two tubes a stop-cock, I, and k, is placed 
 on them, for drawing at pleasure a sample of the liquor returned to the rectifier ; m, n, 
 and o, are tubes communicating on one side with the slanting tube, p, and on the other 
 with the tube, /. These three communications serve to furnish a spirit of greater or 
 less strength. Thus if it be wished to obtain a very strong spirit, the alcoholic vapours 
 which condense in the worm enclosed in e, are all to be led back into the rectifier, r>, 
 to effect which purpose, it is requisite merely to open the stop-cocks, n and o again, 
 weaker spirits may be had by closing the stop-cock, o, and still weaker by closing the 
 stop-cock, n; for in this case, the alcoholic vapours condensed in the worm within e, 
 will flow off into the worm within the upright cooler, f, and will get mixed with the 
 richer vapours condensed in this refrigeratory. The interior of the column, c, contains 
 a series of movable concave scale pans (like those of balances), with spaces between, 
 each alternate pan having the convex side turned reversely of the preceding one, for the 
 purpose of prolonging the cascade descent of the vinasse through c, and exposing it more 
 to the heating action of the ascending vapours ; the edges of these pans are, moreover, 
 furnished with projecting spicules of copper wires, to lead off the liquor from their 
 surfaces in a fine shower. The interior of the rectifier column, d, is mounted with a 
 series of shelves, or floors, the passage from one compartment to that above it being 
 through a short tube, bent at right angles, and open at either end ; p, p, p, is a general 
 tube, for receiving the vapours condensed in each of the turns of the large serpentine 
 Avithin e. The axis of this worm is horizontal ; q, q, q, peep-holes in the top of the 
 wine heater ; r, a tube to conduct the alcoholic vapours not condensed in the worm of 
 e, and also, if desired, those which have been condensed there, into the worm of the 
 refrigeratory, f ; s, a tube to bring the vinasse from the reservoir, g, into the lower part 
 of the cooler, f ; t, a tube to lead the vinasse from the upper part of the cooler, f, into 
 the upper part of the wine-heater, e ; u, a funnel ; v, a stop-cock to feed the tube, t, 
 with vinasse ; x. a tube of outlet for the spirits produced ; it ends, as shown in the figure, 
 in a test tube containing an hydrometer. 
 
 The still of Laugier is represented by a general view in fig. 165. a and b are alembics 
 
 165 
 
 J 
 
 
 
 c 
 
 
 D 
 
 
 
 I 
 
 exposed to the direct action of the fire, and serve a like purpose to those of fig. 164; c, is 
 a cylinder containing the rectifier, and serving as a wine-heater ; n, is the condensing 
 cylinder ; a, a stop-cock communicating with the wine tun ; b, a plunger-tube, fur- 
 nished with a funnel, through which wine runs constantly into the condenser, e ; c, an 
 overflow pipe of d, between c and n, communicating by a tube, dipping in the cylinder, 
 c; d, a plunger equilibrium tube, supplying the alembics with hot wine ; e, a tube 
 leading the vapours of the first alembic, a, into the second one, b, into which it dips ; 
 
STONES. 
 
 237 
 
 /, a tube conducting the vapours of alcohol from the alembic, b, into the circles of the 
 rectifier ; g, a tube bringing back into the alembic, b, the vapours condensed in the 
 circles of the rectifier ; A, a tube conducting the vapours not condensed into the worm 
 of the condenser ; i, a tube serving for the expulsion of the air when the wine comes 
 into the vessel, c ; it communicates with the tube, A, so as not to lose alcohol, j, is a 
 prolongation of the tube d, communicating with the tube A, so that it may be in contact 
 with the external air ; I, a stop cock through which the alcohol condensed runs off into 
 the serpentine ; m, levels, indicating the height of the liquor in the alembics, a and b ; 
 n, tube with a stop cock, for feeding the alembic, a ; o, discharge stop-cock of the spent 
 vinasse (wash). 
 
 A description of the operation of the first still will render that of the second intelligible. 
 
 The alembic, a, being filled three-fourths with vinasse, and b having only 4 or 5 inches 
 of vinasse over its bottom, the liquor in a is made to boil, and the stopcock, r, being at 
 the same time opened, some of the wine to be distilled is allowed to fall into the funnel, 
 u ; this cold liquor runs to the bottom of the cooler, f, fills it, passes into the wine-heater 
 by the tube, I, spreads into a perforated conduit along the top of e, thence trickles down 
 into this vessel till it fills it to the level of the tube, A, by which it is conducted into the 
 column, c, and, flowing down through all its compartments, it falls at last into the 
 second alembic, b. 
 
 During this progress, the liquor of a having begun to boil, the alcoholic vapour passes, 
 by means of the tube e, e, into the second alembic b, which, being heated by these 
 vapours, and by the products of combustion issuing from the fire-place under the first 
 alembic, is also soon made to boil. The vapour which it produces is disengaged into 
 the column of distillation c, meets there the wine which trickles through all its com- 
 partments, transfers to it a portion of its heat, and deprives it of alcohol, goes into the 
 column d, where it is alcoholized afresh, then enters into the worm within the wine- 
 heater e, glides through all its windings, gets stripped in part of the aqueous vapours 
 which accompanied the alcohol, and which return first by the tube p, p, then by 7, I, 
 into the column of rectification ; afterwards the spirituous vapour passes into the worm 
 enclosed in the cooler r, to issue finally condensed and deprived of all the water, 
 wished to be taken from it, by the tube x, into the guage receiver. 
 
 When the indicator/, of the alembic b, shows it to be nearly full, the stop cock a 
 of the alembic a is opened, and the vinasse is allowed to run out entirely exhausted of 
 spirit ; but as soon as thCre are only seven inches of liquor above the discharge pipe, 
 the cock a is shut, and d is opened to run off seven inches of liquor from b. 
 
 It appears, therefore, that in reference to the discharge, the operation is not quite 
 continuous ; but this slight interruption is a real improvement introduced by M. 
 Derosne into the working of M. Blumenthal's apparatus. It is impossible for any 
 distiller, however expert, to exhaust entirely the liquor of the last alembic, if the 
 discharge be not stopped for a short time. The above distilling apparatus requires 
 from two to three hours to put it in full action. From 10 to 15 per cent, of spirit of 
 3 are obtained from the average of French wine ! and 600 litres of such spirit are 
 run off with 150 kilogrammes of coals; or about two old English quarts of spirit for 
 each pound of coals. 
 
 STONES, for building, and bricks, may be proved as to their power of resisting the 
 action of frost, by the following method, first practised \>y M. Brard, and afterwards by 
 MM. Vicat, Billaudel, and Coarad, engineers of the bridges and highways in France. 
 The operation of water in congealing within the pores of a stone may be imitated by 
 the action of a salt, which can increase in bulk by a cause easily produced ; such as 
 efflorescence or crystallisation, for example. Sulphate of soda or Glauber's salt answers 
 the purpose perfectly, and it should be applied as follows : — 
 
 Average samples of the stones in their sound state, free from shakes, should be sawed 
 into pieces 2 or 3 inches cube, and numbered with China ink or a graving tool. A 
 large quantity of - Glauber's salt should be dissolved in hot water, and the solution should 
 be left to cool. The clear saturated solution being heated to the boiling point in a 
 saucepan, the several pieces of stone are to be suspended by a thread in the liquid for 
 exactly one half-hour. They are then removed and hung up each by itself over a vessel 
 containing some of the above cold saturated solution. In the course of 24 hours, if the 
 air be not very damp or cold, a white efflorescence will appear upon the stones. Each 
 piece must be then immersed in the liquor in the subjacent vessel, so as to cause the 
 crystals to disappear, be once more hung up — and dipped again whenever the dry efflores- 
 cence forms. The temperature of the apartment should be kept as uniform as possible 
 during the progress of the trials. According to their tendency to exfoliate by frost, the 
 several stones will show, even in the course of the first day, alterations on the edges and 
 angles of the cubes ; and in 5 days after efflorescence begins, the result will be manifest, 
 and may be estimated by the weight of disintegrated fragments, compared to the known 
 weight of the piece in its original state, both taken equally dry. 
 
238 
 
 SUGAR OF POTATOES. 
 
 STREAM-WORKS. The name given by the Cornish miners to alluvial deposits 
 of tin ore, usually worked in the open air. 
 
 STRINGS. The name given by the Cornish miners to the small filamentous 
 ramifications of a metallic vein. 
 
 SUGAR. The recent researches of the eminent French chemist, M. Casaseca, upon 
 cane-juice, at Havanna in Cuba, have demonstrated clearly the enormous loss which 
 sugar-planters suffer by the imperfection of their manufacturing processes. His results 
 confirm those previously obtained by M. Peligot in Paris, and show that cane-juice 
 evaporated in vacuo at the atmospheric temperature yields, in 100 parts, 
 
 Crystalline white sugar - 20-94 
 
 Water - - - 78-80 
 
 Mineral substances - - - - 0*14 
 
 Organic matter, different from sugar - - 0 - 12 
 
 100-00 
 
 The cane from which the above juice was drawn is called canade la tierra in Cuba. The 
 juice of the Otaheita cane is identical with the preceding. But the proportions of lig- 
 neous fibres in the two canes are very different ; that of la tierra containing, according to 
 M. Casaseca, 16'4 per cent., while that of Otaheita contains only 10. Other canes, how- 
 ever, differ in this respect considerably from these two varieties. The average quantity 
 of grained sugar obtained from cane-juice in our colonial plantations is probably not 
 more than one-third of the quantity of crystalline sugar in the juice which they boil. 
 
 The following analysis of cane-juice, performed by a French chemist, was given me 
 by Mr. Forstall of New Orleans In 10 English gallons, of 231 cubic inches each, 
 of juice marking 8±° Baume, there are 5f ounces English of salts, which consist of — 
 
 Sulphate of potash - - 17 -840 grammes = 15 -44 grains each. 
 
 Phosphate of potash - - 16 028 
 
 Chlorure of potassium - 8*355 
 
 Acetate of potash - - 63-750 
 
 Acetate of lime - - 36*010 
 
 Gelatinous silica - - 15*270 
 
 157-253 = 5*57 ounces avoirdupois. 
 
 To the large proportion of deliquescent saline matter, of which one half, he says, 
 remains in the sugar, the analyst ascribes very properly the deliquescence and dete- 
 rioration of the sugar when kept for some time or transported. It was probably the 
 juice of the cane grown in the rich alluvial soil of Louisiana, and therefore more abun- 
 dant in saline matter than the average soil of our West India islands. The Demerara 
 cane-juice has perhaps the above saline constitution, as it suffers much loss of weight 
 by drainage in the home voyage. 
 
 SUGAR OF POTATOES, GRAPES, or STARCH. About two years ago a 
 sample of sweet mucilaginous liquid was sent to me for analysis, by the Honourable the 
 Commissioners of Customs. It was part of a quantity imported in casks at Hull, from 
 Rotterdam. It was called by the importers, " Vegetable Juice." I found it to be 
 imperfectly saccharified starch or fecula ; and, on my reporting it as such, it was ad- 
 mitted at a moderate rate of duty. 
 
 Three months since I received a sample of a similar liquid from the importer at 
 Hull, with a request that I would examine it chemically. He informed me, that an 
 importation, just made by him of 30 casks of it, had been detained by orders of the 
 Excise, till the sugar duty of 25s. per cwt. of solid matter it contained was paid upon 
 it. It was of specific gravity 1 *362, and contained 80 per cent, of ill-saccharified 
 fecula. 
 
 In the interval between the first importation and the second, an Act of Parliament 
 had been obtained for placing every kind of sugar, from whatever material it was 
 formed, under the provisions of the " Beet- root Sugar Bill." As the saccharometer 
 tables, subservient to the levying of the excise duties, under this Act, were constructed 
 by me, at the request of the President of the Board of Trade, I well knew that 50 per 
 cent, of the syrup of the beet-root was deducted as a waste product, because beet-root 
 molasses is too crude an article for the use of man. Well saccharified starch paste, 
 however, constitutes a syrup, poor indeed in sweetness when compared with cane syrup, 
 or that of the beet-root ; but then it does not spontaneously blacken into molasses, by 
 evaporation, as solutions of ordinary sugar never fail to do when they are concentrated, 
 even with great care. Hence the residuary syrups of saccharified fecula may be all 
 worked up into a tolerably white granular mass, which, being crushed, is used by 
 greedy grocers to mix with their dark -brown bastard sugars, to improve their colour. 
 
 It is only within two years that sugar has been in this country manufactured from 
 potato starch to any extent, though it has been long an object of commercial enterprise 
 
SUGAR OF POTATOES. 
 
 239 
 
 in France, Belgium, and Holland, whert the large coarse potatoes are used for this 
 purpose. The raw material must be very cheap there, as well as the labour ; for potato 
 flour or starch, for conversion into sugar, has been imported from the continent into 
 this country in large quantities, and sold in London at the low price of 10s. per cwt. 
 
 The process usually followed by the potato sugar makers, is to mix -100 gallons of 
 boiling water with every 112 lbs. of the fecula, and 2 lbs of the strongest sulphuric 
 acid. This mixture is boiled about 12 hours in a large vat, made of white deal, having 
 pipes laid along its bottom, which are connected with a high pressure steam-boiler. 
 After being thus saccharified, the acid liquid is neutralized with chalk, filtered, and 
 then evaporated to the density of about 1 -300, at the boiling temperature, or exactly 
 1 "342, when cooled to 60°. When syrup of this density is left in repose for some days, 
 it concretes altogether into crystalline tufts, and forms an apparently dry solid, of spe- 
 cific gravity 1 -39. When this is exposed to the heat of 220°, it fuses into a liquid 
 nearly as thin as water; on cooling to 150°, it takes the consistence of honey, and at 
 100° F. it has that of a viscid varnish. It must be left a considerable time at rest be- 
 fore it recovers its granular state. When heated to 270°, it boils briskly, gives off one- 
 tenth of its weight of water, and concretes, on cooling, into a bright yellow, brittle, but 
 very deliquescent mass, like barley sugar. If the syrup be concentrated to a much 
 greater density than 1 *340, as to 1 *362, or if it be left faintly acidulous, in either case 
 it will not granulate, but will remain either a viscid magma or become a concrete mass, 
 which may indeed be pulverized, though it is so deliquescent as to be unfit for the 
 adulteration of raw sugar. The Hull juice is in this predicament, and is therefore, in 
 my opinion, hardly amenable to the new sugar law, as it cannot by any means be 
 worked up into even the semblance of sugar. 
 
 Good Muscovado sugar, from Jamaica, fuses only when heated to 280°, but it turns 
 immediately dark-brown, from the disengagement of some of its carbon, at that tem- 
 perature, and becomes, in fact, the substance called " caramel" by the French, which is 
 used for colouring brandies, white wines, and liqueurs. 
 
 Thus we see that starch or grape sugar is well distinguished from cane sugar, by its 
 fusibility, at a moderate heat, and its inalterability at a pretty high heat. Its sweet- 
 ening power is only two-fifths of that of ordinary sugar. A good criterion of incom- 
 pletely formed starch sugar is, its resisting the action of sulphuric acid, while perfectly 
 saccharified starch or cane sugar is readily decomposed by it. If, to a strong solution 
 of imperfectly saccharified grape sugar, nearly boiling hot, one drop of strong sulphuric 
 acid be let fall, no perceptible change will ensue, but if the acid be dropped into solu- 
 tions of either of the other two sugars, black carbonaceous particles will make their 
 appearance. 
 
 The article which was lately detained by the Excise, for the high duties, at Hull, is 
 not affected by sulphuric acid, like the solutions of cane sugar, and of the well-made 
 potato sugar of London ; and for this reason I gave my opinion in favour of admitting 
 the so-called vegetable juice at a moderate rate of duty. 
 
 I subjected the solid matter, obtained by evaporating the Hull juice, to ultimate 
 analysis, by peroxide of copper, in a combustion tube, with all the requisite precau- 
 tions, and obtained, in one experiment, 37 per cent, of carbon ; and in another 38 per 
 cent., when the substance had been dried in an air-bath, heated to 275°. The differ- 
 ence to 100, is hydrogen and oxygen, in the proportion to form water. Now this is 
 nearly the constitution of starch, Cane sugar contains about 5 per cent, more carbon, 
 whereby it readily evolves this black element, by the action of heat or sulphuric acid. 
 
 An ingenious memoir, by Mr. Trommer, upon the distinguishing criteria of gum, 
 dextrine, grape sugar, and cane sugar, has been published in the 39th volume of the 
 " Annalen der Chemie und Pharmacie." I have repeated his experiments, and find 
 them to give correct results, when modified in a certain way. His general plan is to 
 expose the hydrate of copper to the action of solutions of the above-mentioned vege- 
 table products. He first renders the solution alkaline, then adds solution of sulphate 
 of copper to it, and either heats the mixture or leaves it for some time in the 
 cold. By pursuing his directions, I encountered contradictory results ; but by the 
 following method, I have secured uniform success, in applying the criteria, and have 
 even arrived at a method of determining, by a direct test, the quantity of sugar in 
 diabetic urine. 
 
 I dissolve a weighed portion of sulphate of copper in a measured quantity of water, 
 and make the solution faintly alkaline, as tested with turmeric paper, by the addition 
 of potash lye, in the cold ; for if the mixture be hot, a portion of the disengaged 
 green hydrate of copper is converted into black oxide. This mixture being always 
 agitated before applying it, forms the test liquor. If a few drops of it be introduced 
 into a solution of gum, no change ensues on the hydrate of copper, even at a boiling 
 heat, which shows that a gummate of copper is formed, which resists decomposition ; 
 but the cupreous mixture, without the gum, is rapidly blackened at the boiling tern- 
 
240 
 
 SULPHATE OF AMMONIA. 
 
 perature. I do not find that the gummate is re-dissolved by an excess of water, as 
 Trommer affirms. 
 
 Starch and tragacanth comport like gum, in which respect I agree with Trommer. 
 Starch, however, possesses already a perfect criterion, in iodine water. Mr. Trommer 
 says, that solution of dextrine affords a deep blue coloured liquid, without a trace of 
 precipitate ; and that when his mixture is heated to 85° C, it deposits red grains of 
 protoxide of copper, soluble in muriatic acid. I think these phenomena are dependent, 
 in some measure, upon the degree of alkaline excess in the mixture. I find, that solu - 
 tion of dextrine, treated in my way, hardly changes in the cold; but when heated 
 slightly, it becomes green, and by brisk boiling an olive tint is produced. It thus be- 
 trays its tendency of transition into sugar. 
 
 Solution of cane sugar, similarly treated, undergoes no change in the cold at the end 
 of two days ; and very little change of colour even at a boiling heat, if not too concen- 
 trated. Cane sugar, treated by Trommer in his way, becomes of a deep blue ; it can 
 be boiled with potash in excess, without any separation of orange-red oxide of copper. 
 
 Starch or grape sugar has a marvellous power of reducing the green hydrate of 
 copper to the orange oxide. I find, however, that it will not act upon the pure blue 
 hydrate, even when recently precipitated ; it needs the addition, in every case, of a 
 small portion of alkali. Yet ammonia does not seem to serve the purpose ; for, in 
 using the ammonia-sulphate of copper, in solution, I obtained unsatisfactory results 
 with the above vegetable products. 
 
 The black oxide of copper is not affected by being boiled in solution of starch sugar. 
 
 " If solution of grape sugar," says Trommer, " and potash, be treated with a solution 
 of sulphate of copper, till the separated hydrate is re-dissolved, a precipitate of red 
 oxide will soon take place, at common temperatures, but it immediately forms, if the 
 mixture is heated. A liquid containing of grape sugar, even one-millionth part," 
 
 says he/ "gives a perceptible tinge (orange), if the light is let fall upon it." To obtain 
 such a minute result, very great nicety must be used in the dose of alkali, which I have 
 found it extremely difficult to hit. With my regulated alkaline mixture, however, I 
 never fail in discovering an exceedingly small portion of starch sugar, even when mixed 
 with Muscovado sugar ; and thus an excellent method is afforded of detecting the 
 frauds of the grocers. 
 
 1 find, that manna deoxidizes the green hydrate of copper slowly when heated, but 
 not nearly to the same extent as grape sugar, which reduces it rapidly to the orange 
 oxide. 
 
 If an excess of the hydrate of copper test be used, there will be a deposit of green 
 hydrate at the bottom of the vessel, under the orange oxide. 
 
 To apply these researches to the sugar of diabetic urine : — This should first be 
 boiled briskly to decompose the urea, and to dissipate its elements in the form of am- 
 monia, as well as to concentrate the saccharine matter, whereby the test becomes more 
 efficacious. Then add to the boiling urine, in a few drops at a time, the cupreous 
 mixture, containing a known quantity of sulphate of copper, till the whole assumes a 
 greenish tint, and continue the heat until the colour becomes bright orange. Should 
 it remain green, it is a proof that more hydrate of copper has been introduced than has 
 been equivalent to the deoxidixing power of the starch sugar. I have found that one 
 grain of sulphate of copper in solution, supersaturated very slightly with potash, is de- 
 composed with the production of orange protoxide, by about 3 grains of potato sugar; 
 or, more exactly, 30 parts of the said sulphate, in the state of an alkaline hydrate of 
 copper, pass altogether into the state of orange oxide, by means of 100 parts of granular 
 starch sugar. Thus, for every 3 grains of sulphate so changed, 10 grains of sugar may 
 be estimated to exist in diabetic urine. 
 
 Acetate of copper may be used in the above experiments, but it is not so good as the 
 sulphate. The chloride of copper does not answer. 
 
 Specific gravity is also an important criterion, applied to sugars ; that of the cane 
 and beet-root is 1 \577 ; that of starch sugar, in crystalline tufts, is 1 \39, or perhaps 1 *40, 
 as it varies a little with its state of dryness. At 1*342, syrup of the cane contains 70 
 per cent of sugar ; at the same density, syrup of starch sugar contains 15\ per cent, of 
 concrete matter, dried at 260° F., and therefore freed from the 10 per cent, of water 
 which it contains in the granular state. Thus, another distinction is obtained between 
 the two sugars, in the relative densities of their solutions, at like saccharine contents 
 per cent. 
 
 SULPHATE OF AMMONIA. This salt, now so extensively used in preparing 
 artificial manures and imitations of guano, for farmers, is made of great purity, and at 
 an economical rate, by the patent process of Mr. Croll, described under the article 
 Gas. A mixture of 10 per cent, of this sulphate with 20 of bone-dust, some gypsum, 
 and farmyard manure, will form a very fertilising compost, applicable to a great 
 variety of soils. 
 
TEA. 
 
 241 
 
 SULPHURIC ACID. A valuable improvement of the process for manufacturing 
 this fundamental chemical agent has been lately contrived by M. Gay Lussac, and 
 made the subject of a patent in this country by his agent M. Sautter. It consists in 
 causing the waste gas of the vitriol chamber to ascend through the chemical cascade of 
 M. Clement Desormes, and to encounter there a stream of sulphuric acid of specific 
 gravity 1 ■ 750. The nitrous acid gas, which is in a well regulated chamber always 
 slightly redundant, is perfectly absorbed by the said sulphuric acid ; which, 4hus im- 
 pregnated, is made to trickle down through another cascade, up through which passes 
 a current of sulphurous acid, from the combustion of sulphur in a little adjoining 
 chamber. The condensed nitrous acid gas is thereby immediately transformed into 
 nitrous gas (deutoxide of azote) which is transmitted from this second cascade into the 
 large vitriol chamber, and there exercises its well known reaction upon its aeriform 
 contents. The economy thus effected in the sulphuric acid manufacture is such that 
 for 100 parts of sulphur 3 of nitrate of soda will suffice, instead of 9 or 10 as usually 
 consumed. . 
 
 Upon the formation of sulphated nitrous gas (NO 2 , 3 SO 3 , 2 H O), and its com- 
 bination with oil of vitriol, the manufacture of hydrated-sulphuric acid is founded. 
 Either sulphur is burned in mixture with about one-ninth of saltpetre; whence along 
 with sulphurous acid gas, nitrous oxide gas is disengaged, while sulphate of potash 
 remains ; thus K O, N0 5 +S<=S0 3 + N0 2 , K O. 2. Or, nitric acid in the fluid or 
 vaporous form may be present in the lead-chamber, into which the sulphurous acid 
 gas passes, in consequence of placing in the flimes of the sulphur a pan, charged with 
 a mixture of sulphuric acid and nitre or nitrate of soda. This nitric acid being 
 decomposed by a portion of ' the sulphurous acid, there will result sulphuric acid and 
 nitrous gas. By the mutual re-action of the sulphurous and nitric acids, sulphuric 
 acid and nitrous gas will be produced ; N O 5 + 3 S O = N O 2 + 3 S O 3. 3. Or, 
 by heating sugar or starch with nitric acid, the mixture of nitrous gas and nitrous 
 acid vapour which results, may be thrown into the chamber among the sulphurous 
 acid. In any one of these three cases, sulphurous acid gas, nitrous acid vapours (pro- 
 ceeding from the mixture of nitrous oxide and atmospherical oxygen) and steam are 
 mingled together ; whence arises the crystalline compound of sulphated nitrous oxide 
 with sulphuric acid, which compound subsides in white clouds to the bottom of the 
 chamber, and dissolves in the dilute oil of vitriol placed there, into sulphuric acid, 
 with disengagement of nitrous gas. This gas now forms, with the remaining atmo- 
 spherical oxygen, nitrous acid vapours once more, which condense a fresh portion of 
 sulphurous acid gas into the above crystalline compound ; and thus in perpetual 
 alternation. 
 
 Sulphurous acid gas does not act upon nitrous gas, not even upon the nitrous acid 
 vapour produced by the admission of oxygen, if water be absent ; but the moment that 
 a little steam is admitted the crystalline compound is condensed. The presence of 
 much sulphuric acid favours the formation of the sulphated nitrous gas. These 
 crystals are decomposed by tepid water with disengagement of nitrous gas, which 
 seizes the oxygen present and becomes nitrous acid (hyponitric of many chemists). 
 
 T. 
 
 TEA. This well-known plant has recently acquired peculiar interest among men 
 of science, both in a chemical and physiological point of view. In its composition it ap- 
 proaches by the quantity of azote it contains to animalized matter, and it seems thereby 
 qualified, according to Liebig, to exercise an extraordinary action on some of the func- 
 tions of animals, especially the secretion of bile. The chemical principle characteristic 
 of tea, coffee, and cocoa beans, is one and the same when equally purified, from which- 
 ever of these substances it is extracted ; and is called indifferently either Theine or 
 Caffeine. Mulder takes it from tea, by treating the evaporated extract by hot water, 
 with calcined magnesia, filtering the mixture, evaporating to dryness the liquor which 
 passes through, and digesting the residuum in ether. This solution being distilled, 
 the ether passes over, and the theine remains in the retort. This principle is extracted 
 in the same way from ground raw coffee and from guarana, a preparation of the 
 seeds of Paullinia, highly valued by the Brazilians. Theine, when pure, crystallises 
 in fine glossy needles, like white silk, which lose, at the heat of boiling water, 8 per 
 cent, of their weight, constituting its two atoms of water of crystallisation. These 
 needles are bitter tasted. They melt at 350° F., and sublime at 543° without decom- 
 posing. The crystals dried at 250° dissolve in 98 parts of cold water, 97 of alcohol, 
 and 194 parts of ether. In their ordinary state, they are but little more soluble 
 in these menstrua. Theine is a feeble base, and is precipitable by tannin alone from 
 its solutions. 
 
 I i 
 
242 
 
 TEA. 
 
 Mr. Stenhouse prepares theine by precipitating a decoction of tea with solution of 
 acetate of lead, evaporating the filtered liquor to a dry extract, and exposing this 
 extract to a subliming heat in a shallow iron pan, whose mouth is covered flatly with 
 porous paper luted round the edges, as a filter to the vapour, and surmounted with a 
 cap of compact paper, as a receiver to the crystals. In this way he obtained, at a 
 maximum, only 1-37 from 100-00 of tea. But M. Peligot, from the quantity of 
 azote amounting to about 6 per cent., which he found in the tea leaves, being led to 
 believe that much more theine existed in them than had hitherto been obtained, adopted 
 the following improved process of extraction. To the hot infusion of tea, subacstate 
 of lead and then ammonia were added ; through the filtered liquor a current of sul- 
 phuretted hydrogen was passed to throw down all the lead, and the clear liquid being 
 evaporated at a gentle heat afforded, on cooling, an abundant crop of crystals. By 
 re-evaporation of the mother liquor, more crystals were procured, amounting altoge- 
 ther to from B to 6 out of 1 00 of tea. 
 
 The composition of theine may be represented by the chemical formula, O*, H&, N 2 , 
 O 2 ; whence it appears to contain no less than 29 per cent, of nitrogen or azote. 
 
 Peligot found, on an average, in 100 parts of — 
 
 Parts soluble in boiling Water. 
 Dried black teas - - - - -43-2 
 
 green teas - - - - 47 *1 
 
 Black teas, as sold - 38-4 
 Green teas, ditto - - - - - 43*4 
 
 Tea, by Mulder's general analysis, has a very complex constitution; 100 parts 
 contain — 
 
 
 Green. 
 
 Black. 
 
 Essential oil (to which the flavour is due) 
 
 - 0-79 
 
 0 60 
 
 Chlorophyle (leaf-green matter) 
 
 - 2-22 
 
 1-84 
 
 Wax - 
 
 - 028 
 
 
 Resin - 
 
 - 2-22 
 
 3*64 
 
 Gum - - - - 
 
 - 8-56 
 
 7'28 
 
 Tannin - 
 
 - 17-80 
 
 12-88 
 
 Theine - 
 
 - 0-43* 
 
 0-46 
 
 Extractive matter - 
 
 - 22-80 
 
 19-88 
 
 Do. , dark -coloured 
 
 
 1-48 
 
 Colourable matter separable by muriatic acid 
 
 - 23-60 
 
 19-12 
 
 Albumine - - - - 
 
 - 3-00 
 
 2-80 
 
 Vegetable fibre - 
 
 - 17-08 
 
 28-32 
 
 Ashes - - - 
 
 - 5-56 
 
 5-24 
 
 Since the proportion of azote in theine and caffeine is so much greater than even in 
 any animal compound, urea and uric acid excepted, and since so many different nations 
 have been, as it were, instinctively led to the extensive use of tea, coffee, and chocolate 
 or cocoa, as articles of food and enlivening beverage, which agree in no feature or 
 property, but in the possession of one peculiar chemical principle, we must conclude 
 that the constitution of these vegetable products is no random freak of nature, but that 
 it has been ordained by Divine Wisdom for performing beneficial effects on the human 
 race. Hitherto, indeed, medicine, a conjectural art, exercised too much by men super- 
 ficially skilled in the science of nature, and the slaves or abettors of baseless hypotheses, 
 has laid tea and coffee generally under its ban, equally infallible with the multitude, 
 as that of the Pope in the older time, and has denounced their use, as causing a variety 
 of nervous and other nosological maladies. But Chemistry, advancing with her 
 unquenchable torch into the darkest domains of Nature, has now unveiled the mystery, 
 and displayed those elemental transformations of the organic functions in the human 
 body, to which tea and coffee contribute a salutary and powerful aid. 
 
 Liebig, in his admirable researches into the kingdoms of life, has been led to infer 
 that the bile is one of the products resulting from the decomposition of the animal 
 tissues, and that our animal food may be resolved by the action of oxygen, so amply 
 applied to the lungs in respiration, into bile and urea, the characteristic constituent of 
 urine. 
 
 When the consumption of tissue in man is small, as among mankind in the artificial 
 state of life, with little exercise and consequently languid digestion, assimilation, and 
 decomposition, the constant use of substances rich in azotised compounds, closely ana- 
 logous to the chief principle of the bile, must assist powerfully in the production of this 
 secretion, so essential to the healthy action of the bowels and other organs. Liebig 
 has fully proved that the bile is not an excrementitious fluid, merely to be rejected, as 
 
 * This constituent is obviously much underrated. 
 
TEA. 
 
 243 
 
 a prejudicial inmate of the system, but that it serves, after secretion, some important 
 purpose in the animal economy, being, in particular, subservient to respiration. 
 
 I shall conclude these remarks, perhaps more appropriate to a work on chemistry than 
 to the present, by stating the relation between theine and the animal product taurine, 
 the characteristic constituent of bile. 
 
 One atom of theine - = C 8 , N 2 , H 5 , O 2 "J Two atoms of taurine. 
 Nine atoms of water - = H 9 , O 9 V = c 8 , N 2 , H M , O 20 . 
 
 Nine atoms cf oxygen = 0 9 J 
 
 The letters C, N, H, O, denote carbon, nitrogen or azote, hydrogen, and oxygen ; and 
 the figures attached to each, the number of atoms ; one atom of carbon being 6, one of 
 azote 14, one of hydrogen 1, and one. of oxygen 8; from which the composition of 
 the bodies, theine and taurine, may be easily computed for 100 parts. Now, supposing 
 one tenth of the bile to consist of solid matter, and this solid matter to be choleic acid 
 (resolvable into taurine but different from it), which contains 3*87 of nitrogen, then 
 2-8 grains of theine would afford to 480 grains of bile (supposed solid, or 4,800 grains 
 in its ordinary state) all the nitrogen required for the constitution of taurine, its pe- 
 culiar crystalline principle. 
 
 Jt may be remarked here, however, with regard to tea and coffee, that while they 
 agree in the main feature, they differ in some others, and especially in the large pro- 
 portion of tannin in the former, and its non-existence, according to my experiments, in 
 the latter, notwithstanding the statement of its presence in many chemical works. 
 Hence, tea may act injuriously in persons of Cretian habits*, while coffee has no con- 
 stipating power, however much it may cause excitement and heat under certain idio- 
 syncrasies. 
 
 A pure, agreeable, and convenient concentrated preparation of tea and coffee has 
 been recently made the subject of an ingenious patent by Mr. Staite, which I can re- 
 commend as being made from the best articles In the market, by a perfectly wholesome 
 apparatus and process. The patentee has printed a little explanatory pamphlet on the 
 object of his improvement, from which the following extracts are taken : — 
 
 " The quantity of tea grown and consumed in China cannot be ascertained, but the 
 consumption of Europe and America may be taken as follows i — 
 
 Russia - - - 6,500,000 lbs. 
 
 United States of America 8,000,000 
 
 France - 2,000,000 
 
 Holland - - - 2,800,000 
 
 Other countries - - 2,000,000 
 
 Great Britain - - 50,000,000 
 
 71,300,003 lbs. or 31,830 tons. 
 
 " The number of tea-dealers in the year 1839 was, in England, 82,794; in Scotland,. 
 13,611 ; and in Ireland, 12,744; making a total of 109,179. It is presumed that in 
 consequence of the increased population their number at present must exceed 120,000. 
 
 " The observations of Liebig afford a satisfactory explanation of the cause of the great 
 partiality of the poor not only for tea, but for tea of an expensive and superior kind. 
 He says, ' We shall never certainly be able to discover how men were first led to the 
 use of the hot infusion of the leaves of a certain shrub (tea), or of a decoction of cer- 
 tain roasted seeds (coffee). Some eause there must be, which will explain how the 
 practice has become a necessary of life to all nations. But it is still more remarkable, 
 that the beneficial effects of both plants on the health must be ascribed to one and the 
 same substance (theine or caffeine), the presence of which in two vegetables, belonging 
 to natural families, the products of different quarters of the globe, could hardly have 
 presented itself to the boldest imagination. Yet recent researches have shown, in such 
 a manner as to exclude all doubt, that theine and caffeine are in all respects identical.' 
 And he adds, ' That we may consider these vegetable compounds, so remarkable for 
 their action on the brain, and the substance of the organs of motion, as elements of 
 food for organs as yet unknown, which are destined to convert the blood into ner- 
 vous substance, and thus recruit the energy of the moving and thinking faculties*' 
 Such a discovery gives great importance to tea and coffee, in a physiological and 
 medical point of view. 
 
 " At a meeting of the Academy of Sciences, in Paris, lately held, M. Peligot read a 
 paper on the Chemical Combinations of Tea. He stated, that tea contained essential 
 principles of nutrition, far exceeding in importance its stimulating properties ; and 
 showed that tea is, in every respect, one of the most desirable articles of general use. 
 
 * Titus, chap. i. v. 12. 
 I i 2 
 
244 
 
 TOBACCO. 
 
 One of his experiments on the nutritious qualities of tea, as compared with those of 
 soup, was decidedly in favour of the former. 
 
 " Coffee is grown in Brazil, Cuba, Hayti, Java, British West Indies, Dutch Guiana, 
 States of South America, French West India Colonies, Porto Rico, Sumatra, Ceylon, 
 Bourbon, Manilla and Mocha. Brazil produces the largest quantity, 72,000,000 
 pounds weight ; and the other states and colonies according to the order in which they 
 are enumerated, down to Mocha, which produces the least, or 1,000,000 pounds; 
 making a total of 346,000,000 pounds, equal to the consumption of the enormous 
 quantity of 2,900 tons weekly, or 150,800 tons per annum. 
 
 " From the official returns, the quantities of coffee exported in one year from the 
 different places of production were 154,550 tons ; — 
 
 
 TONS. 
 
 
 TONS. 
 
 To France 
 
 - 29,650 
 
 Denmark 
 
 - 1,400 
 
 U. S. of America - 
 
 - 46,070 
 
 Spain 
 
 1,000 
 
 Trieste 
 
 9,000 
 
 Prussia 
 
 930 
 
 Hamburg - 
 Antwerp - 
 
 - 20,620 
 
 Naples and Sicily 
 
 640 
 
 - 10,000 
 
 Venice 
 
 320 
 
 Amsterdam 
 
 8,530 
 
 Fiume 
 
 170 
 
 Bremen 
 
 4,500 
 
 Great Britain (average of lOyrs. ) 18,250 
 
 St. Petersburg 
 
 2,000 
 
 
 
 Norway and Sweden 
 
 1,470 
 
 
 1 54,550 
 
 " Every reflecting man will admit, that articles of such vast consumption as tea and 
 coffee (amounting together to more than 185,000 tons annually), forming the chief 
 liquid food of a whole nation, must exercise a great influence upon the health of the 
 people, and that any discovery which tends to the purification of these alimentary 
 drinks, rendering them more wholesome, without rendering them less agreeable, is a 
 great boon conferred upon society. 
 
 " The inventor and manufacturers of the ' Pure Concentrated Fluid Essence of Tea 
 and Coffee,' hope that the convenient and portable form in which they are enabled to 
 offer them to the public (in ' Rand's Patent Collapsible Tubes,' made of pure tin, 
 whereby all the usual trouble and inconvenience of making tea and coffee are avoided), 
 affords rational grounds (in addition to more important considerations) for anticipating 
 an extensive sale." 
 
 TOBACCO. This important subject of our national revenue has been, during the 
 last session of parliament, very fully investigated, in reference to the smuggling and 
 adulteration carried to an enormous extent, and hitherto but little checked by all the 
 efforts of the officers of the customs and excise. Mr. Joseph Hume, >M. P., who 
 moved the appointment of the committee of the House of Commons, and of which he 
 was chairman, proposed a reduction of duty from 3s. 2d. a pound to Is., as the only 
 effectual remedy against these joint evils; but he was counteracted by Mr. Goulbourn, 
 chancellor of the exchequer, and a majority of the members of the committee, on the 
 score that the state of the national finances did not permit such a defalcation of income 
 as that reduction would occasion. It would appear, from a great mass of evidence, 
 that much more tobacco is introduced illicitly than what duty is paid upon, and that 
 very great adulterations are practised. The following statement shows the tempta- 
 tions : — 
 
 Virginia leaf costs in bond 3Arf. per lib., the duty is 1,100 per cent. 
 Ditto strips „ 6§<f. „ 700 
 
 Kentucky leaf „ Ud. „ 1,200 
 
 Ditto strips „ 4%d. „ 8C0 
 
 Havannah cigars „ 8.v. „ • 112 
 
 Manilla cheroots „ Gs. ,, 150 
 
 East India cheroots ,, Is. „ 900 
 
 Negrohead and Cavendish Gd. „ 1,8L0 
 
 Rates of duty on tobacco in foreign countries : — 
 
 Austria — leaf tobacco - 
 Belgium ditto - 
 Bremen ditto, a per cent, ad valorem 
 Denmark leaves and stems 
 Prussia - "1 
 
 Saxony 
 
 Bavaria - I Zoll-Verein ) 
 
 Brunswick - \ States j 
 
 Wiirtemberg 
 Frankfort on the Maine! 
 
 Per English 
 Pound. 
 
 3r/. 
 
 2d. 
 
 Per English 
 Pound. 
 
 Other German States - 
 Hamburgh § per cent, ad valorem. 
 Holland 2 per cent, ad valorem. 
 
 Ditto, cigars - 
 Ionian islands, leaf stems 
 
 Ditto, manufactured 
 Russia 30 per cent, ad valorem on 
 
 foreign. 
 
 Sweden and Norway . - about Id. 
 
 2d. 
 3d. 
 
TOBACCO. 
 
 24o 
 
 A strict royal monopoly (reyie) exists in Austria Proper, France, Sardinia, the 
 Duchies of Parma and Lucca, and the Grand Duchy of Tuscany ; and in Portugal, 
 Spain, Naples, and the States of the Church, the licence to manufacture is periodically 
 sold to companies, which regulate the prices of tobacco as they please. It will be 
 found that the situation of all these countries where the monopolies and high prices 
 are kept up, is nearly the same, as to illicit trade in tobacco, as in England. 
 
 In the years 1841, 1842, and 1843, the average revenue in this country on tobacco, 
 at 3s. 2c?. per lb., was 3,635,105/. 
 
 The greater part of the committee's report is occupied with the examination of wit- 
 nesses as to the extent, modes, facilities, and chief localities of the illicit trade. It 
 exhibits a great body of very curious and useful information, and demonstrates, beyond 
 a doubt, that no measure short of a reduction of the duty to Is. per lb. can put a stop 
 to it. 
 
 The portion of the Report most interesting to the readers of the present work will 
 probably be found to be the scientific evidence as to the means of detecting adul- 
 teration. 
 
 The society of tobacco manufacturers in London, desirous of ascertaining how far 
 chemistry could detect adulteration in tobacco, mixed four samples with different 
 materials. No. 1. contained 5 per cent, of refined sugar ; No. 2. 10 per cent, of extra- 
 neous matter, viz. sugar and common salt ; No. 3. 15 per cent, of extraneous matter, 
 the one half of it sugar, and the other half a certain powder used by the trade ; No. 4. 
 15 per cent, also, consisting of about 3 parts sugar, and 1 part terra japonica (catechu). 
 These four samples were placed in the hands of Mr. A. Garden, chemist, of Oxford 
 Street, for analysis, who made the following report upon their composition : — 
 
 " The leaves of the tobacco-plant, in addition to the vegetable principles of which 
 they are chiefly composed, are known to contain a considerable number of saline and 
 earthy substances, and which no doubt ought to be regarded as legitimate constituents 
 of the plant. The proportion which these saline substances bear to the whole vege- 
 table mass is, it is true, but small, yet it becomes a question how far the presence of 
 these salts, in quantities somewhat larger than those in which they are generally found to 
 exist, can fairly be referred to a process of adulteration. The five samples of tobacco 
 sent to me for examination do not appear to differ very widely from one another. 
 After the removal of all the vegetable matter, they have, on an average, yielded 14 per 
 cent, of solid substances, consisting of soluble and insoluble saline and earthy com- 
 pounds, the principal of which are as follow : sulphate and phosphate of lime, car- 
 bonate of potash, muriate of ammonia and soda, sulphate of iron, malate of lime, and 
 siliceous earth. The specimens marked 1, 2, and 4*, are exceedingly similar ; that marked 
 genuine contains about 2 per cent, less than the others, and the specimen No. 4. (3. as 
 stated above) is remarkable for having yielded a proportion of oxide of iron, which 
 would almost lead to the supposition that sulphate of iron had been introduced. The 
 other samples, it is true, also afforded evidence of the presence of iron, but in such 
 minute quantity as might easily be accounted for by the contact of iron vessels or 
 instruments, in the transports or manipulations to which the articles may have been 
 exposed. 
 
 (Signed) "A. Garden." 
 
 Mr. Rogers, chairman of the Tobacconists' Society, who superintended the adultera- 
 tion, states that no iron or copperas was put into any of them ; that Mr. Garden had 
 them some time under process, having received them in May or June, and having made 
 his report on the 26th of August, 1843. " The manufacturers, in consequence of that 
 report, came to the conclusion that the analysation was not satisfactory, and could not 
 be done, so far as that process was concerned." v 
 
 Mr. Joseph Hume, M. P., under instructions from the committee, requested two 
 chemists, Mr. Heathfield and Mr. Edward Solly, jun., each to prepare six samples in 
 the presence of two members of the committee. That was done, and the samples were 
 sent to the Excise Board, and during ten or twelve days were carefully analysed by the 
 three chemists employed by the board to detect adulteration. The evidence of these 
 three gentlemen, viz. Professor Graham, Mr. Richard, and Mr. George Phillips, will 
 explain the course they took to carry on the analysis; and the following are the re- 
 sults : — 
 
 * 6 in the original, but altered by me to 4, as denoting the fourth of the adulterated samples. The 
 fifth was genuine tobacco. 
 
246 
 
 TOBACCO. 
 
 Particulars of Six Samples of Tobacco, prepared 
 as above, in the presence of Sir Charles 
 Douglas, M.P., and tylr. Ewart, M.P., Mem- 
 bers of the Committee. 
 
 No. I., marked X. 
 i lbs. 8 oz. of tobacco, with 1 lib. 8 oz. of garden 
 rhubarb leaves, about 16 per cent., or 12£ per 
 cent, in 100 parts. 
 
 No. II., marked K. 
 I lbs. 6 oz. of tobacco, with 1 lib. foxglove leaves. 
 About 10 per cent, added, or 9^2_ i n 100 parts. 
 
 No. III., marked N. 
 11 lbs. 11 oz. tobacco, mixed with 8 oz. brown 
 paper, soaked in decoction of sarsaparilla. 10i 
 oz. syrup of sugar, combining solid sugar, 7 or 
 8 dwts. ; 1 oz. of saltpetre, and £ oz. of alum ; 
 in all, 18A oz. About 8 per cent, added, or 7 54 
 in 100 parts. 
 
 No. IV., marked F. 
 11 libs. 14 oz. of tobacco, mixed with chicory 
 root, dried and powdered, Irish moss gluten- 
 ised, carbonate of potash, sulphate of potash, 
 carbonate of magnesia, and carbonate of lime, 
 about 9 oz., or about 5| per cent., or 4 in 100 
 parts. 
 
 No. V., marked O. 
 13 lbs. 9 oz. of tobacco, mixed with 12 oz. of 
 ground tobacco stalks. 
 
 No. VI., marked R. 
 11 libs. 4 oz. No adulteration. 
 
 Report of the Analysis of the first Series of Six 
 Samples, by Messrs. Richard Phillips, Gra- 
 ham, and George Phillips, 7th June, 1844. 
 
 No. I., marked X. 
 Adulterated with the leaves of garden rhubarb ; 
 the amount of the adulteration is estimated at 
 3 3 per cent. 
 
 No. II., marked K. 
 Adulterated by a green leaf, not tobacco, which 
 appears to belong to a plant of the same natural 
 family, probably the potato ; the amount of the 
 adulteration estimated at 3'9 per cent. 
 
 No. III., marked N. 
 Adulterated with brown paper or millboard, and 
 also with sugar; the amount of the first adul- 
 teration is estimated at 6 per cent., of the second 
 1£ or two per cent. 
 
 No. IV., marked F. 
 Adulterated with a vegetable matter, not tobacco, 
 the nature of which we are not agreed upon. 
 The amount of this adulteration is estimated at 
 T2 per cent. There is reason to suspect the 
 addition to this tobacco of both sand and sugar, 
 in small quantity. 
 
 No. V., marked O. 
 Adulterated with sand and sugar ; the amount of 
 the first adulteration is estimated at 2 per cent.; 
 of the second at 3 per cent. 
 
 No. VI., marked R. 
 Genuine, but with a proportion of sand unusually 
 
 high. 
 
 No. V., marked B. 
 Not adulterated at all. 
 
 No. VI., marked M. 
 Not adulterated at all. 
 
 Particulars of Six Samples of Tobacco, mixed 
 and sealed up at Mr. Rogers's, 392. Oxford 
 Street, in the presence of Sir Charles Douglas 
 and Mr. Ewart, by Edward Solly, jun. Esq. 
 
 No. I., marked C. 
 
 Adulterated with sugar of milk - - 5 
 
 Terra japonica - - 1 
 
 Nitrate of potash 1 
 
 Alum ------ 1 
 
 Total per cent. - - 8 
 
 No. II., marked L. 
 
 Adulterated with refined sugar - 3 
 
 Terra japonica 1 
 
 Carbonate of potash - - - - 1 
 
 Common salt ----- 1 
 
 Total per cent. - - 6 
 
 No. III., marked Q. 
 
 Adulterated with refined sugar - - 2 
 
 Crude nitrate of ammonia - - - 4 
 
 Common salt - - - - 1 
 
 Muriate of potash ... - 0*5 
 
 Nitrate of potash - - - - 0 5 
 
 Alum 10 
 
 Total per cent. - - 9 
 
 No. IV., marked P. 
 
 Adulterated with sugar of milk - - 5 
 
 Refined sugar - - - - 3 
 
 Common salt ----- 1 
 
 Carbonate of potash 1 
 
 Total per cent. - 10 
 
 Second Series of Six Samples, signed Rogers and 
 Son, marked as under, analysed by Messrs. 
 Richard and George Phillips, and Thomas 
 Graham. 
 
 No. I., marked C. 
 Adulterated with sugar, the adulteration esti- 
 mated at 1 per cent. 
 
 No. II., marked L. 
 Adulterated with sugar, the adulteration esti- 
 mated at 3 per cent. 
 
 No. III., marked Q. 
 Adulterated with sugar, the adulteration esti- 
 mated at 2 per cent. 
 
 No. IV., marked P. 
 Adulterated with sugar, the adulteration esti- 
 mated at 4 per cent. 
 
 No. V., marked B. 
 Genuine ; grains of sugar were, however, found m 
 it and picked out, but the quantity so small, that 
 we allow their introduction to be accidental. 
 
 No. VI., marked M. 
 Adulterated with loaf-bread,which has been cut up 
 in the same manner as the tobacco ; the amount 
 of this adulteration was not estimated, but is 
 small ; the sample contains also a little sugar. 
 
TOBACCO. 
 
 247 
 
 It appears from the preceding statement, that the chemists made no attempt at a 
 true chemical analysis, but contented themselves with a physical examination of the 
 appearances, and with the single process of fermentation to detect Sugar, by the produc- 
 tion of alcohol ; and yet they declare the presence of sugar in the tobacco which con- 
 tained none ; as in samples F, O, and B. They did not search for saline matter, such 
 as nitrate of potash, alum, common salt, nitrate of ammonia, muriate of potash, or 
 carbonate of potash, and in fact do not seem to have made any analytical research for 
 any such foreign bodies ; so that if the sugar had been left out (as a skilful adulterator 
 would have done), and if the foxglove leaves had been well browned by tobacco juice, 
 none of the adulterations would have been detected. 
 
 Mr. R. Phillips says, in his examination before the Committee, " generally speaking 
 we did not employ chemical tests," but it was principally by mechanical analysis and ex- 
 amination of the plant that they judged. When asked if he could obtain alcohol from 
 sugar of milk, Mr. R. Phillips replies, " I think not." Question 1555. 
 
 " 7597. Chairman. — Will you (Mr. R. Phillips) look at your report, letter C, 
 adulterated with sugar estimated at 1 per cent. ; I asked you the question, whether 
 you could discover the adulteration, if made with sugar of milk? and your answer was 
 No, I believe not, for I think it would not ferment. 
 
 " 7598. That specimen was mixed with 5 per cent, of sugar of milk, and 3 per cent, 
 of other articles, earthy matters, making altogether 8 per cent. ; your report is, 
 ' adulterated with sugar, estimated at 1 per cent. ;' how do you reconcile your detect- 
 ing sugar there, when you said that you could not detect sugar of milk? — I said that 
 I spoke from the best of my recollection, and that is my recollection." 
 
 " 7632. Letter O, you (Mr. R. Phillips) report as being ' adulterated with sand and 
 sugar ; the amount of the first estimated at 2, and the second at 3 per cent.,' therefore 
 that is reported as adulterated to the extent of 5 per cent. ? — Yes. 
 
 " 7633. That specimen is stated to be < 13*pounds 9 ounces of tobacco mixed with 
 12 ounces of ground stalk;' what should you say to that? Are you perfectly satisfied 
 that the sugar in this specimen was foreign matter ? — I have no doubt of it ; and with 
 respect to the increased quantity of sand, that might come in with the increased quan- 
 tity of stalks, which always contain a larger quantity than leaf tobacco. 
 
 " 7637. But are you the least shaken in your opinion as to this analysis, by its being 
 stated to you, that that which was presented to you was tobacco mixed with 12 ounces 
 of stalk? Not the least, neither with respect to sugar nor sand ; confirmed with respect to 
 sand, and not shaken ivith regard to sugar." 
 
 " 7640. Here is an addition of eight per cent, of stalk ; do you imagine that that 
 would give two per cent, of sand upon the whole amount? — It seems a large amount, 
 but I cannot account for it in any other way ; it would increase it, but I cannot say to 
 what amount." 
 
 " 7645. Taking the specimen letter Q, on which you were before examined, in which 
 you have stated, « adulteration at 2 per cent. ; ' if informed that eight per cent, of 
 muriate of potash, and other soluble matters were mixed, do you not consider that 
 tobacco might be adulterated by those matters, which you could not discover as 
 adulterations, to the extent of 5 or 6 per cent., without the possibility of detec- 
 tion ? — I think they might, with such matter as that, without the possibility of 
 detection." 
 
 Mr. R. Phillips says, in answer to Question 7673, that he never saw nicotine, and 
 " never saw anybody that saw it." Now he has seen me often, and I have a specimen 
 of pure nicotine, which I showed to the Committee in my examination, and which I 
 shall be happy to show him at any time. 
 
 " Mr. George Phillips called in and examined. 
 
 " 7767. What situation do you hold in the excise? — That of an examiner. 
 
 " 7768. What are the duties of an examiner ? — They are various, but I have been 
 employed chemically. 
 
 " 7769. How long have you been in that situation ? — About two years. 
 
 " 7773. Have you been educated as a chemist? — No, I am self-educated. 
 
 " 7775. Have you examined all those specimens which have been suspected to be 
 adulterated tobacco? — Yes, I have examined the whole of them. 
 
 " 7776. And you were employed at Gainsborough, Liverpool, and Manchester, in 
 those different seizures and trials which took place ? — Yes, I was present at the whole 
 of them. 
 
 " 7777. You were also associated with Mr. Richard Phillips and Professor Graham, 
 in making inquiries into the 12 samples submitted to you? — Yes. 
 
 " 7780. What time did you take in making these experiments? — I think we were 
 about 12 days. 
 
 " 7781. In examining the 12 specimens? — Yes. 
 
 " 7782. Did you sign the report? — Yes." 
 
248 
 
 TOBACCO. 
 
 His process of examination consists in drying the tobacco thoroughly by a heat of 
 from 176° to 182°, in then weighing out 100 grains of it, in digesting that weight in 
 21 pints of water of the above temperature, stirring the mixture with a glass rod, leaving 
 it to infuse for 50 minutes, and then separating the liquid from the insoluble matter by 
 a fine strainer or filter. The insoluble part is gently pressed, dried at the above heat, 
 and weighed. In this way Mr. Phillips found, that 
 
 Ligneous. Extractive. 
 
 Virginia hand, the entire leaf and stem gave - 46 54 
 
 Virginia, stripped, the stem being taken out - 49 51 
 
 Do. do. - - 47 53 
 
 Kentucky hand - - - - 50 50 
 
 Do. do. - 55-8 44-2 
 
 Do. stripped - 54-8 45*2 
 
 Do. do. .... 53-3 46-7 
 
 Maryland, not stripped - - - 56 '9 43-1 
 
 Do. do. - - - 57-7 42-3 
 
 Mean of Virginia hand experiments - - 46 54 
 
 Do. do. stripped do. - - - 48 52 
 
 Do. Kentucky hand - 52-9 47-1 
 
 Do. do. stripped - 54 05 49*95 
 
 Do. do. do. - 57'3 42-7 
 
 After experimenting upon between 500 and 600 different samples, he has never found 
 any to exceed the highest of the above which is 54 ; though he calls it, in his subse- 
 quent examination, 55 of extract. 
 
 Ligneous. Extractive. 
 
 Porto- Rico tobacco-leaf gave - - - 70 30 
 
 Columbia do. - - - - 61*5 38-5 
 
 Do. do. - - - - 60-8 39-2 
 
 Virginia stalks - - - - 48-5 51*5 
 
 Kentucky do. - - - - - 64-1 35*9 
 
 Do. do. - - - - - 66 4 33-6 
 
 Turkey -_ - - - - 46-8 53-2 
 
 " 7865. Do you know to what natural family tobacco belongs? — Mr. G. Phillips. 
 I am not a botanist. 
 
 " 7867. Take the foxglove for instance? — I cannot say whether it belongs to the 
 same family. I know it has not the same character ; it is essentially different in cha- 
 racter." 
 
 Yet the sample marked K, which contained foxglove, maladroitly introduced in the 
 green state, and thus easily distinguishable by the least experienced eye from tobacco, 
 was pronounced by the three chemists to be " adulterated by a green leaf, not tobacco, 
 which appears to belong to a plant of the same natural family, possibly the potatoe." 
 Digitalis belongs to the family Scrophularia?, not the Solaneae, like tobacco. 
 
 By selecting such tobaccos from the above tables as abound in ligneous matter, im- 
 buing them with a quantity of some cheap vegetable extracts not fermentable into al- 
 cohol, drying and pressing them properly, it would be easy to adulterate tobaccos to the 
 amount of 10 or more percent., and set at defiance this scheme of Mr. G. Phillips. 
 The manufacturer has of course a stock of Virginia tobacco at hand, capable of yield- 
 ing a like proportion of extract, to cover his deception, which he puts into their hands, 
 pour leur donner le change. 
 
 " 7869. What is the power of microscope you employ? — About 60,000." 
 
 Does Mr. G. Phillips mean to say that the linear magnifying power of his micro- 
 scope is 60,000 ? There is no such instrument in existence. If he means the area is 
 enlarged by his microscope 60,000 times, he ought to have said so, and the linear power 
 in that case would be about 245 times. 
 
 " 7877. In what manner do you obtain saline Tnatter from the tobacco? — I first as- 
 certained the amount of ashes: I took 100 grains of Virginia leaf; I burned it to a 
 red heat, not sufficiently high to drive off any thing beyond the carbonaceous matter ; 
 those 100 grains of Virginia leaf produced 10*5 of ashes, and it contained 1*8 of sand 
 or silica. The next experiment upon the same leaf gave ashes 1 1 -2, and precisely the 
 same amount of sand as the other 1*3. The next was upon stalk alone, 100 grains of 
 the same tobacco stalk ; it gave ashes 16*5, and -4 of sand. The next, stalk and leaf, 
 was upon 62 grains, which gave ashes 8-2, and '5 of sand (13-2 and 0-8 per cent.). 
 Now we come to the Kentucky; 100 grains of the Kentucky leaf gave ashes 19'5, 
 sand 1 *4 ; ditto 18*4 and 1 -4 ; 47 grains of stalk and leaf gave ashes 9*5 and sand -8 ; 
 (20 and 17 percent.); 100 grains of stalk gave 20*4 and '9. Another experiment 
 
TOBACCO. 
 
 249 
 
 gave the same." Here we have nearly double the proportion of sand from leaf that 
 there is from stalks. 
 
 Let us compare these experiments of Mr. G. Phillips with the unlucky counter- * 
 statement of Mr. R. Phillips. The former actually finds in the one set of stalks only 
 
 of 1 per cent, of sand, and 1 T 3 5 , or upwards of three times as much in the leaf; 
 while, in the other set, he finds about one half of sand in the stalks of what was in the 
 leaf. Now Mr. R. Phillips defers to Mr. G. P. as his standard authority on this point. 
 Thus, 
 
 " Question 7580. You (Mr. R. Phillips) are not able to state the exact amount of 
 those saline matters which exist in the different kinds of tobacco ? — No, I have never 
 tried. 
 
 " 7582. You have not, up to this time, made that experiment in the various inquiries 
 you have made? — No, I have not. I have not thought it necessary." 
 
 "7583. You state that the earthy matter found " (in the ashes) " is silica ; do you 
 mean sand ? — Yes. 
 
 " 7584. What is the greatest or the smallest quantity you have found in the 
 genuine tobacco ? — I have not got the proportion ; I perhaps could find it, but I have 
 it not with me. 
 
 " 7585. You do not know the minimum or the maximum ? — No, but I believe that 
 can he stated by Mr. George Phillips very accurately." 
 
 " 7633. . — (Answer of Mr. R. Phillips. ) " With respect to the increased quan- 
 tity of sand, that might come in with the increased quantity of stalks, which always 
 contain a larger quantity than leaf tobacco." 
 
 "7634. Would the proportion of sand be accounted for, in your opinion, by the 
 introduction of 12 oz. of stalks? ■ — ■ T think it would." 
 
 Why did not the two Messrs. Phillips compare notes beforehand ? 
 
 "7878. Besides silica, what did you (Mr. G. Phillips) find ? — Number 36., which 
 produced 19 '5 ; gave carbonate of lime 7*3 grains, silica 14, carbonate of potash, and 
 a trace of iron 9 *7 grains * ; that is, it showed the presence of iron, but there was no 
 appreciable quantity. The object of separating it into lime and potash was, that if 
 there had been an introduction of 5 per cent, of potash, I should have had an increased 
 amount of extractive matter " (soluble, he should say) "and an increased amount of 
 ashes; in genuine tobacco, where the extractive proportion is high, the ashes are 
 low."f 
 
 " 7885. Are there any other articles found, besides the silica and carbonate of lime 
 and potash ? — Not by my mode : both lime and potash exist in tobacco, in various 
 quantities, malate and nitrate, and so on ; but the amount of each has never been found' 
 by any one. \ 
 
 " 7918. ■ — Ans. The only two kinds of tobacco manufactured worth speak- 
 
 ing of are Virginia and Kentucky, and they come in strips principally. Now the to- 
 bacco-manufacturer might endeavour to defeat us in this way ; suppose we endeavour 
 to tie him down, he might mix his tobacco not in the proportion that we expect. " 
 
 The Excise, though it has no power to tie the manufacturers down so hard and fast 
 that they may not use any duty-paid tobacco which they please, yet it is too apt to give 
 rise to a spirit of evasion. When a low-priced Kentucky, poor in extract is laid down, 
 it may be easily enriched with 10 per cent, of some vegetable extract to bring it up to 
 Mr. G. Phillips' standard Virginia pitch of 55. 
 
 " 7924. Have you subjected the extract to the process of combustion, in order to as- 
 certain its amount of saline matter ? — Not the extract ; I make a point of preserving 
 part, in order to experiment upon." 
 
 Yet he immediately afterwards declares he makes no experiments upon it. 
 
 " 7928. What do the ashes of C consist of? — We did not try that beyond the sand. 
 
 " 7929. You have got the ashes 16 by combustion? — Yes we suspected this sample 
 to contain sugar, and also tried for sand." 
 
 " 7934. Could you not find alum ? — Yes, but it would be impossible to try for the 
 various salts that might be put in tobacco ; you might be experimenting for years on 
 one sample." 
 
 Relatively to Mr. R. Phillips' explanation of the rationale of the production of sand, 
 question 7961 to Mr. G. Phillips affords a flat contradiction. " Could the introduction 
 of 12 ounces of ground stalk into 13 pounds 9 ounces of tobacco, give an adulteration of 
 3 per cent, of sand? — It is perfectly impossible ; the stalk contains less sand than the 
 leaf. 
 
 " 8032. In any of those 12 specimens that you examined, were you able to distin- 
 * An extraordinary quantity. 
 
 t How easy to give this character to tobacco by adding extractive matter from different plants I 
 X What a rash assertion ! He missed an uniform and main constituent, the phosphate of lime. 
 
250 
 
 TOBACCO. 
 
 guish any vegetable mixture besides the tobacco ? — We readily distinguished in K, 
 the mixture of foxglove and rhubarb." 
 
 There was no rhubarb in K ; the foxglove was unluckily conspicuous by its light 
 green colour, and easily picked, out. Answer to Question 7858. " So also as regards 
 the rhubarb, the rhubarb is very full of massy strong hairs, which are something like 
 bodkins rather round; they are larger at the end ; in fact, where the points of the hairs 
 of tobacco are small, the rhubarb swell out and increase and cross each other in various 
 directions, while those of the tobacco are flattened at the top." 
 
 Has the foxglove the same massy hairs as the rhubarb? 
 
 With regard to the production of alcohol from the samples of adulterated tobacco, 
 Mr. E. Solly, in his examination before the Committee, makes the following observ- 
 ations in answers to Questions 8350. 8352. " Then you do not consider the mode by 
 which saccharine matter is said to be detected at present to be a good and sufficient 
 test ?— I should receive it with very great caution. 
 
 " 8352. — Ans. " I believe that tobacco contains substances that may give rise to 
 the formation of spirit ; therefore I think it possible, until the contrary has been proved, 
 that spirit may be formed from fermenting pure tobacco." 
 
 Seven samples of tobacco, mixed under the superintendence of the Committee, as 
 above described, were sent to me on the 18th of June last, for analysis, marked B B, 
 C C, F F, M M, 0 0, Q Q, X X, which I now presume were of like composition to 
 the parcels marked B, C, F, M, O, Q, X, in those sent to the Excise. As I operate 
 always alone in my laboratory, I required naturally a considerable time to perform the 
 several sets of experiments which I deemed requisite in trying to detect adulterations in 
 so heterogeneous a compound as tobacco. In my first examination before the Com- 
 mittee, on the 15th July, I stated that my first line of research had been to determine the 
 proportion of azote in each of the above specimens, and compare it with that in genuine 
 tobacco, with the view of ascertaining into which of the parcels, non-azotised plants, 
 such as rhubarb and other indigenous leaves, might have been introduced. For this 
 purpose I took a weighed portion of each tobacco, dried it thoroughly by a gentle 
 steam heat, and found thereby how much moisture it contained. — See 2d table below. 
 
 Ammonia. Azote. 
 
 
 
 in 100 grains. 
 
 B B when dry afforded, by ignition with hydrate of 
 
 
 
 soda and quicklime, in an appropriate apparatus - 
 
 2-55 
 
 = 2-1 
 
 C C afforded 
 
 2-49 
 
 = 1-89 
 
 FF „ 
 
 2-38 
 
 = 1-96 
 
 MM „ - 
 
 3-06 
 
 = 2-52 
 
 0 0 
 
 2-72 
 
 = 2*24 
 
 QQ „ 
 
 3-6 
 
 = 2-97 
 
 XX „ 
 
 2-72 
 
 == 2-24 
 
 Virginia (genuine) - 
 
 2-6 
 
 = 2-14 
 
 I was now convinced that no good purpose could be served by this process of ana- 
 lysis, since it appeared that the differences in the proportions of azote resulting from 
 the different proportions of nicotine, albumen, gluten, &c, in the tobacco, were too 
 slight, and most probably too variable, from soil, climate, and mode of culture, to be 
 relied on as tests of purity ; and more especially when I found, on trial, that the dried 
 leaves of foxglove afforded 1 -96, or nearly 2 per cent, of azote, and that this plant was 
 one likely to be used in making the adulterations. Besides, it appears that X X, which 
 I now perceive to have contained 16 per cent, of rhubarb leaves, afforded as much 
 azote as O O, which was altogether tobacco. Practical chemists are aware that each 
 of the above experiments requires no little time, as well as nicety of manipulation, 
 The results may, I believe, be depended on ; they were derived in each case from the 
 decomposition of 50 grains of the dried tobacco. I next dried by a gentle heat, con- 
 tinued for several hours, as long as weight was lost, 200 grains of each sample. 
 
 
 
 Dry. 
 
 Water 
 
 
 >ec. Grav. 
 
 Residuum 
 
 Soluble 
 Matter or 
 Extract. 
 
 BB lost 
 
 
 at70°F. 
 
 
 Infusion. 
 
 dried. 
 
 11-75 per cent, and 1 00 gr. + 1 000 
 
 
 1-017 
 
 59-5 
 
 40-5 
 
 cc „ 
 
 14-5 
 
 
 >» 
 
 
 1-0184 
 
 54 
 
 46-0 
 
 FF „ 
 
 15 
 
 » 
 
 »> 
 
 
 1-017 
 
 60 
 
 40 
 
 MM „ 
 
 14-75 
 
 »» \ 
 
 j> 
 
 
 1-015 
 
 71 
 
 29 
 
 OO „ 
 
 15-5 
 
 
 5> 
 
 
 1-018 
 
 62 
 
 38 
 
 QQ „ 
 
 17-5 
 
 
 »> 
 
 
 1-021 
 
 72 
 
 28 
 
 XX „ 
 
 17-75 
 
 » 
 
 
 
 1-019 
 
 67 
 
 33 
 
 Virginia leaf 
 
 6-5 
 
 » 
 
 J> 
 
 
 1-015 
 
 53 
 
 47 
 
TOBACCO. 
 
 251 
 
 In a second series of experiments, where 100 grains of each of the dried tobaccos, as 
 under, were digested for two hours in 4000 grains of distilled water, at the temperature 
 of 176° F., the following results were obtained : 
 
 Dried Residuum. Soluble or Extract. 
 
 BB - - 567 43-3 
 
 CC - - 56-0 44-0 
 
 FF - - 54-7 45*3 
 
 MM - - 63-7 36-3 
 
 OO - - 58-2 41-8 
 
 QQ - - 54-0 46-0 
 
 XX - - 57-7 42-3 
 
 Thus, by a longer digestion with heat, and a larger quantity of water, more soluble 
 matter or extract is obtained, and also in different proportions, from the same samples. 
 
 Dried Residuum. Soluble or Extract. 
 Havannah tobacco - 60*1 39*9 
 
 Cuba - - - 62-1 37-9 
 
 Virginia - - 53*9 46*1 
 
 Kentucky - - 57 -2 42-8 
 
 It may, moreover, be remarked that none of the tobaccos, either adulterated or genuine, 
 yielded so great a proportion of extract as Mr. G. Phillips asserts. 
 
 It will be observed from the table of the specific gravity of the infusions of 100 
 grains of the respective tobaccos, in 1000 grains of water, at 70° F. (with trituration 
 in a mortar), that QQ afforded the densest liquor, having a specific gravity of 1-021. 
 I was hence led to imagine that this sample was adulterated with some soluble sub- 
 stances, and possibly with sugar, of which such a handle had been made in the Excise 
 prosecutions. I therefore boiled 1000 grains of that sample with 5000 grains of dis- 
 tilled water, and evaporated the soluble matter to a solid extract, which weighed 400 
 grains. These were next digested in 3000 grain-measures of alcohol of 0-834, and they 
 left 330 grains insoluble in this menstruum. The matter insoluble in alcohol should 
 have contained the sugar if any were present ; but when it was treated with nitric acid 
 of proper density and temperature, it afforded no oxalic acid whatever ; even by the test 
 of chloride of calcium. Hence I inferred that if sugar had been mixed with that 
 tobacco, it could not be discovered by probably the best test of sugar in common cir- 
 cumstances ; and indeed, on looking now into the actual composition of sample Q, we 
 find it to contain only 2 per cent, of sugar, mixed with 4 of nitrate of ammonia, 1 of 
 common salt, 1 of the mixed nitrates of potash and muriate of potash, and one of alum. 
 As the infusion of 100 grains of X X in 1000 of water was next in density, being 1 -019 
 I treated 1000 grains of it as I had done with QQ,, and obtained 600 grains of watery 
 extract, which, being digested in alcohol, left 330 grains like the preceding. When 
 this also was treated with nitric acid, it afforded no oxalic. I therefore abandoned this 
 line of research as unprofitable. 
 
 It occurred to me that muriate or nitrate of ammonia might have been employed in 
 adulterating some of the samples of tobacco. To ascertain this point I distilled 100 
 grains of each sample along with water and quick-lime, condensing the vapours, and 
 testing the distilled liquid for ammonia : — 
 
 BB afforded - 0-68 of ammonia. 
 
 CC .... 0-34 
 
 FF - 0-347 
 
 MM „ - - - - 0-51 „ 
 
 OO .... o-238 
 
 QQ „ - - - - 0-765 
 
 XX - - - - 0-68 „ 
 
 Kentucky - - ... . o\58 „ 
 
 Virginia - - - - -0-64 „ 
 
 Ammonia exists in the saline state in all tobaccos, but here in QQin notable excess, 
 corresponding to the 4 per cent, of crude nitrate of ammonia, which had been intro- 
 duced by the mixers. So far this experiment has a positive result. 
 
 The filtered cold infusions of 100 grains of each dried sample in 1000 grains of dis- 
 tilled water were examined by many chemical tests, as follows : — 
 
 1. Virginia taken as a standard : 
 
 Infusion pale brown ; acid reaction with litmus paper ; nitrate of barytes, O ; nitrate 
 of silver, a faint opalescence, but no curdy precipitate ; oxalate of ammonia, a faint 
 cloud of calcareous matter ; water of ammonia, O ; chlorure of tin, a faint white pre- 
 cipitate — hence no sulphuretted hydrogen present ; chloride of platinum, a copious 
 
 K k 2 
 
252 
 
 TOBACCO. 
 
 white precipitate, from the ammoniacal salt present ; acetate of lead, an abundant 
 whitish precipitate, soluble in nitric acid ; chloride of iron caused a green tint, and 
 sulphate of copper an olive brown, both resulting from the yellow of the iron and blue 
 of the copper solutions with the brown of the tobacco. 
 
 B B afforded the same results with the above tests as the Virginia tobacco : hence it 
 might be inferred to be free from soluble sulphates, muriates, carbonates, &c. 
 
 C C, acid reaction like the preceding ; nitrate of barytes, a precipitate which, being 
 drained on a filter, washed, dried, and ignited, weighed 2 2 grains; resulting, as it now 
 appears, from the 1 per cent, of alum introduced into that sample. 
 
 F F afforded 2 -6 sulphate of barytes, resulting from the sulphate of potash introduced 
 into this sample. 
 
 M M afforded 0*6 of sulphate of barytes, a quantity belonging to this description of 
 tobacco, derived, no doubt, from the soil — indicating possibly the proportion that 
 should be deducted from that afforded by C C and F F. 
 
 OO afforded 0*5 of sulphate of barytes, indicating freedom from any added 
 sulphate. 
 
 QQ» 1 grain of sulphate of barytes, corresponding to the 1 per cent, of alum, which 
 was possibly not uniformly diffused through the parcel ; so that probably more of it 
 existed in the portion taken for experiment of C C, than in that taken of QQ. 
 
 X X, sulphate of barytes, 0 8 ; the small excess here over pure tobacco due to the 
 admixture of rhubarb leaves. It is to be observed, that all these barytic precipitates 
 were insoluble in nitrie acid. 
 
 After separation by the filter of the barytic precipitates, from the infusions made 
 with heat, a definite quantity of solution of nitrate of silver was added to each at once, 
 because it was found impossible to define the point at which that test ceased to produce 
 a change. The phenomena here were singular and puzzling. The phials containing 
 the infusions of B B, C C, F F, O O, had their sides coated with a lively green film, 
 that with XX slightly; those containing M M and QQ, with a brown film; as also 
 those from the Virginia, Kentucky, Havannah, and Cuba tobaccos ; while the contents 
 of F F remained turbid after many days. From these phenomena, it appears that 
 nitrate of silver cannot be advantageously used as a test upon infusions of tobacco made 
 with hot water. 
 
 When the infusions of the tobaccos are made in the cold, those hydrogenated princi- 
 ples, which seem to reduce a portion of the oxide of the nitrate of silver, and render its 
 precipitate insoluble in ammonia, are not apparently generated. The nitrate of silver 
 in this case gave the following results. 
 
 BB out of 100 grains infused, yielded - -1-8 chlorsilver. 
 
 cc - - - ■ - i-o 
 
 MM - - - - - 1-3 
 
 These quantities belong to genuine tobacco, as I found on trying the Virginia. The 
 precipitates were insoluble in nitric acid. 
 
 My next series of experiments was instituted to determine, by fermentative action, 
 with the addition of good yeast to the infusions of the respective samples, whether 
 sugar could be detected in any of them by the production of alcohol. Accordingly, I 
 infused half a pound avoirdupois, = 3500 grains, of each in 4000 grains of boiling water, 
 strained off the liquor into wide-mouthed phials, introduced into each 800 grains by 
 weight of the best fresh porter-yeast from Messrs. Meux's brewery in my neighbour- 
 hood, and enclosed them all in a space, kept at the temperature of 80° F. The specific 
 gravity of each, before the yeast, was very nearly 1 -08. After 40 hours, the specific 
 gravities were found to be (at 80°) of : — 
 
 BB - - 1-055 OO - - - 1-049 
 
 CC - - 1-062 QQ - - - 1-0645 
 
 FF - - 1-055 XX - - - 1-0575 
 
 MM - - - 1-056 
 
 The contents of F F being distilled carefully in glass vessels, 700 water-grain 
 measures of liquid were drawn off, which, at 70° F., had the specific gravity, 0-9921. 
 
 The contents of O O afforded 700 grain measures of specific gravity, 0 9876; besides 
 500 grain measures of 0*9974. 
 
 Contents of B B afforded 700 grain measures of 0-9946, and 240 grain measures of 
 0-998. 
 
 From 2400 grains by weight of the yeast, 700 grain measures of liquor were distilled 
 off, at specific gravity, 0 983. 
 
 On the hypothesis that the liquor distilled from the infusions of the three samples of 
 tobacco were alcoholic, the 700 grains of F F would contain about 10 per cent, of proof 
 spirit, or nearly 70 grains. 
 
TOBACCO. 
 
 253 
 
 Alcoholic spirits of 0-983 specific gravity contain 23*3 per cent, of proof spirit; hence 
 7 x 23 '3 = 163*1 grains, of which one third = 54*4 grains, being the product of 800 grains 
 of yeast, had been introduced into each of the tobacco worts. The product of F F is 
 therefore 70 — 54 '4= 15*6 grains of proof spirit, containing about 7 grains of alcohol — a 
 paltry result, and much too fallacious, whereon to found a fiscal persecution, as we 
 shall presently show. 
 
 OO, yielded 700 grain measures of 0-9876, equivalent to 16 per cent, of proof spirit 
 = 112 grains, besides 500 grains of 0*9974, equivalent to 3 '2 per cent, of proof = 16 grains 
 of proof; together =128 grains, from which 54*4 being deducted on account of the 
 yeast spirit, there remain 73*6 of apparent spirit, as the product of the tobacco wash of 
 half a pound of O O. 
 
 B B, afforded 760 grains at 0*9946, representing 6*7 per cent, of proof=50 grains of 
 proof; to which 8| grains for 240, at 0*998, the sum 58i represents the whole obtained 
 for this wash, and 54| being deducted for the yeast spirit, there will remain 4 grains of 
 proof spirit, corresponding to 2 grains of alcohol and 4 grains of sugar in 3500 grains of 
 the tobacco.* 
 
 The only inference that can be drawn from these results of experiments carefully con- 
 ducted on the principles assumed as certain by Professor Graham and the Messrs. Phil- 
 lips, is that the sample OO contained 73*4 grains or thereby of sugar mixed in the 
 half pound of tobacco; that F F sample contained about 15*6 grains, and B B, 4 ; 
 whereas, as it appears in the published report that there was no sugar in any one of the 
 three samples, the fallacy of the excise process is manifest. 
 
 It would therefore seem, that infusions of tobacco without sugar, when mixed with 
 brisk yeast, and placed for 40 hours in a temperature of about 80°, undergo a certain 
 degree of decomposition ; attended with a diminution of their specific gravity, or, in the 
 vulgar language of the Excise, they suffer attenuation. This phenomenon offers no diffi- 
 culty to any one conversant with organic chemistry. He knows that there are no 
 fewer than twelve different species of fermentation, all involving a specific series of 
 decompositions and recompositions, each occupied with its appropriate subject, and ge- 
 nerating peculiar products. See Fermentation in this Supplement. I shall advert, in 
 this place, merely to that marvellous metamorphosis which bitter almonds experience 
 by contact of pure water ; during which, aided by heat alone, the solid inert matter of 
 the kernel is converted into a volatile, pungent, poisonous, ethereal oil, mixed with hy- 
 drocyanic or prussic acid, a fluid lighter than water. Such remarkable changes must 
 be well known to Mr. R. Phillips and Professor Graham, and ought to have made 
 them hesitate before they pronounced a distilled fluid, which is destitute of the smell 
 and taste of alcohol, and which they do not say they had submitted to the requisite 
 ordeal, to be this substance. 
 
 If by fermenting the infusion of 3500 grains of tobacco, my distilled products were 
 so slight and fallacious, what could the chemist get from 1000 grains? or, as Mr. Gra- 
 ham is wont to operate, from 200 grains, or less than half an ounce ? See Question 
 7548. Have they ever converted their supposed alcohol into ether, have they made 
 fulminating mercury by its means, or have they extracted olefiant gas out of it ? If 
 not, their testimony would have been scouted in any of our great courts of judicature. 
 
 If sugar be present in any notable proportion, I think that it should be found by eva- 
 porating the watery extract to dryness, digesting the extract in alcohol, and then treating 
 the residuum properly with nitric acid. From the quantity of oxalic acid formed, the pro- 
 portion of sugar might possibly be approximately estimated. I am not aware that there are 
 any principles in tobacco itself which would give rise to the formation of oxalic acid ; but 
 this point could be easily set at rest by preliminary experiments. I tried this 
 method, and obtained, as I have stated, no oxalic acid from the samples subjected to the 
 process. 
 
 The last series of experiments which I made upon the samples of tobacco sent to me 
 by the Committee, was the incineration of 500 grains of each in a platinum basin, and 
 the analysis of the ashes. The results per cent, were as follows : — 
 
 
 Total ashes 
 in 100. 
 
 Carbonate 
 of potash. 
 
 Silica. 
 
 Phosphate 
 of lime. 
 
 Carbonate 
 of lime. 
 
 Sulphate 
 of barytes. 
 
 Chloride 
 of silver. 
 
 BB 
 
 15 
 
 1*6 
 
 2*4 
 
 2*8 
 
 7*1 
 
 1*4 
 
 2*6 
 
 CC 
 
 156 
 
 2- 166 
 
 2-0 
 
 3*8 
 
 5-2 
 
 3*0 
 
 0-7 
 
 FF 
 
 16*3 
 
 1*82 
 
 29 
 
 24 
 
 8-1 
 
 1-5 
 
 0*5 
 
 MM - 
 
 16*4 
 
 1-75 
 
 3 1 
 
 4-2 
 
 6*3 
 
 1-66 
 
 5-0 
 
 O O 
 
 13*2 
 
 1*82 
 
 2-6 
 
 1*6 
 
 54 
 
 135 
 
 0*6 
 
 QQ - - 
 
 160 
 
 2*4 
 
 1*6 
 
 37 
 
 49 
 
 32 
 
 37 
 
 XX - 
 
 14*2 
 
 2*66 
 
 11 
 
 1 CO-6) 
 
 2 I 07 J 
 
 2*1 
 
 6*4 
 
 1*6 
 
 04 
 
 Virginico leaf 
 
 12*6 
 
 1*65 
 
 21 
 
 6*8 
 
 1*1 
 
 095 
 
 Kentucky 
 
 1325 
 
 3*00 
 
 0-6 
 
 2*2 
 
 lost 
 
 1*25 
 
 lost 
 
 * I have not deemed it necessary to convert water-grain measures into weights, or vice versa, in this 
 frivolous speculation. 
 
254 
 
 TOBACCO. 
 
 The results here stated may be relied on, as they were the mean of many very deli- 
 berate experiments. They show that there are great variations in the proportions of 
 the constituents, even in the five genuine tobaccos ; B B, M M, O O, Virginia and 
 Kentucky. But the alum in C C and Q,Q, is indicated by the larger proportion of 
 sulphate of barytes, obtained by precipitating the matter soluble in water, and acidu- 
 lated with nitric acid, by means of nitrate of barytes. The sulphate o? potash in F F 
 had been probably decomposed into carbonate during the ignition, along with carbonate 
 of lime and carbonaceous matter ; and has thereby escaped notice in the column of 
 sulphate of barytes. 
 
 I tried each of the aqueous infusions of the fresh samples with solution of gelatine, 
 but obtained no indication of tannin, as should have happened with C C, inconsequence 
 of the introduction into it, of 1 per cent, of terra japonica or catechu. 
 
 Finally, I regret, exceedingly, that so short a space of time was allowed me for 
 making and digesting all these various researches, prior to my examinations before the 
 Committee. Even my report supplementary to my oral evidence, was given in before 
 I had finished my experiments on the action of nitric acid upon the tobacco extracts, 
 and hence I mention there my having obtained crystals of oxalic acid, which turned 
 out upon further examination to be no such thing. 
 
 The following analysis of 10,000 parts of fresh tobacco, by Posselt and Reimann, 
 will show the exceeding complexity of this substance : — 
 
 Chloride of potassium - - 6*3 
 
 Potash combined with malic and nitric acids 9-5 
 
 Phosphate of lime - - ]6 6 
 
 Lime in union with malic acid - 24 2 
 
 Silica - - - 8-8 
 
 Woody fibre - - 496- 9 
 
 Water (traces of starch) - - 8828 0 
 
 Nicotine 
 Nicotianine 
 
 Extractive matter, slightly bitter 
 Gum with a little malate of lime 
 Green resin 
 Vegetable albumen 
 Substance analogous to gluten 
 Malic acid 
 Malate of amonia - 
 Sulphate of potash 
 
 1 
 
 287 
 
 174 
 26-7 
 26-0 
 
 104-8 
 5C0 
 120 
 4-8 
 
 In SWiman's Journal, vol. vii. p. 2., a chemical examination of tobacco is given by 
 Dr. Covell, which shows its components to have been but imperfectly represented in the 
 above German analysis. He found, 1. gum; 2. a viscid slime, equally soluble in water 
 and alcohol, and precipitable from both by subacetate of lead; 3. tannin ; 4. gallic acid ; 
 5. chlorophyle (leaf-green) ; 6. a green pulverulent matter, which dissolves in boiling 
 water, but falls down again when the water cools ; 7. a yellow oil, possessing the smell, 
 taste, and poisonous qualities of tobacco ; 8. a large quantity of a pale yellow resin ; 
 9. nicotine ; 10. a white substance, analogous to morphia, soluble in hot, but hardly 
 in cold, alcohol ; 11. a beautiful orange-red dye stuff, soluble only in acids : it defla- 
 grates in the fire, and seems to possess neutral properties; 12. nicotianine. In the 
 infusion and decoction of the leaves of tobacco, little of this substance is found ; but 
 after they are exhausted with ether, alcohol, and water, if they be treated with sul- 
 phuric acid, and evaporated nearly to dryness, crystals of sulphate of nicotianine are 
 obtained. Ammonia precipitates the nicotianine from the solution in the state of a 
 yellowish white, soft powdering matter, which may be kneaded into a lump, and is void 
 of taste and smell, as all its neutral saline combinations also are: its most characteristic 
 property is that of forming soluble and uncrystallisable compounds with vegetable 
 acids. 
 
 According to Buchner, the seeds of tobacco yield a pale yellow extract to alcohol, 
 which contains a compound of nicotine and sugar. Repertorium far die Pharmacie, 
 vol. xxxii. 
 
 MM. Henry and Boutron Charlard found in 
 1000 parts of Cuba tobacco 
 Maryland - 
 Virginia 
 lie et Vilaine 
 Lot et Garonne 
 times more than were obtained by Posselt and Reimann. 
 
 I shall conclude this examination of the Tobacco Report with a few remarks upon the 
 pretences of the Messrs. Phillips and Graham to botanical and microscopic skill in dis- 
 tinguishing the minutest filaments of shag tobacco from those of other plants. Having 
 applied a good achromatic microscope to this object along with my son, who is familiar 
 with the use of that instrument, I must acknowledge that I would place exceedingly 
 little reliance on the possibility of distinguishing such vegetable leaves as I could easily 
 select for the adulteration of tobacco ; and I will engage to set at fault even the 
 superior accomplishments of Professor Lindley. 
 
 " 699.9. When a vegetable fibrous addition is made to the ordinary tobacco, and so 
 ground and minutely divided as not to allow an examination by the glass, could you 
 
 8*64 of nicotine 
 5-28 
 
 10- 00 
 
 11- 20 
 8-20; 
 
 quantities from 12 to 19 
 
TOBACCO. 
 
 255 
 
 distinguish it from tobacco?" — Mr. Graham's answer: " It would be extremely diffi- 
 cult to divide it so finely as not to present a sensible magnitude to the microscope. I 
 have never met with tobacco manufactured for sale as shag tobacco, in which I could 
 not distinguish it." 
 
 Mr. R. Phillips, in reply to question 7511., " Generally speaking, we did not employ 
 any chemical tests." 
 
 "7512. Then it was principally by mechanical analysis, and examination of the 
 fibre of the plant, that you.judged? — Yes, certainly." 
 
 Answer to question 7523 : " You may distinguish it (tobacco) not by the naked eye, 
 but by the microscope." 
 
 " 7857. Can you (Mr. G. Phillips) distinguish the fibre of tobacco from the fibre of 
 dock, or any other vegetable of the same family? — Yes." 
 
 " 7856. In how small a quantity can you detect it? — However small the quantity, 
 if you take pains, you can discover it : nothing can be finer than the sample K, in 
 which there was foxglove." 
 
 Professor Lindley and Mr. George Phillips distinguish tobacco from other plants chiefly 
 by the structure of its hairs. But in Geiger's Pharmaceutische Botanik, the second 
 edition, improved by Nees von Esenbeck, and Heinrich Dierbach, a book of standard 
 authority, the Nicotiana tabacum of Linnaeus, which is the Florida tobacco of the 
 French botanists, is described as having smooth (glabra) somewhat glutinous leaves. 
 Several varieties of this plant are said to be cultivated under peculiar provincial names, 
 to which the Nicotiana petiolata, Nicotiana decurrens, &c, belong; all with smooth and 
 blistery leaves. 
 
 In my examination before the Committee on the 15th of July, in answer to Question 
 8569., I said, — "The conclusion to which I am led is this, that when the tobacco is 
 brought in this shag state, it is next to impossible, by chemical means in most cases, or 
 by physiological means, to determine the adulteration ; the only case in which adul- 
 teration can be detected, in my opinion, is when sugar is mixed. 
 
 "8570. Does the presence of alcohol, by distillation from a fermented solution, give 
 you an invariable test that sugar is present ? — If sugar is present in any quantity 
 above 5 per cent., I think alcohol may be produced from it." 
 
 But I would never content myself with the deceptious test of the specific gravity of 
 a minute portion of the distilled liquid. I would take at least seven pounds of the sus- 
 pected tobacco, rinse it rapidly in cold water, in order to dissolve out the saccharine 
 matter, with as little as possible of the tobacco extract ; mix it with a certain quantity 
 of yeast; take the specific gravity of the mixture ; set it in a chamber heated to 80° Fah., 
 and watch the phenomena of fermentation, if any occur. At the end of 40 hours, or 
 whenever the density of the mixture had sunk to the lowest point, I would note it ; 
 then distil, rectify the distilled liquor, and expose it to the appropriate tests of alcohol, 
 as stated above. I am quite convinced that no certainty could be obtained by operating 
 upon the infusion of 200 grains of a tobacco containing 5 or 1 0 per cent, of sugar, as Pro- 
 fessor Graham, in his evidence before the magistrates in the Gainsborough prosecution, 
 said he had done with the tobacco then in question. The total quantity of sugar 
 that could be present was under 20 grains, and this being mixed with tobacco juice, 
 which counteracts the fermentative process, would afford a most unsatisfactory quantity 
 of alcohol — a quantity most difficult of verification ; one on which, in my humble appre- 
 hension, knowing, as I do, the fallacy of chemical experiments and experimenters, 
 no person should ever venture to seek a verdict, or to levy a heavy fine. 
 
 " 8589. Then you are of opinion that it will be impossible, if care be taken, such as 
 you state, by chemists, for detection to be within the power of the government? — 
 Quite impossible. I will pledge my chemical character to make such specimens as 
 the Excise cannot detect. 
 
 " 8590. Then to continue the system of alleged detection by analysis might subject 
 individuals to punishment most unjustly. 
 
 "8591. Have any cases come under your knowledge of errors in judgment upon 
 that point?- — There is a case which has lately occurred to me of a very unjustifiable 
 kind on the part of the Excise, and I think I might mention it. It is a case of pepper. 
 
 " 8592. Will you describe the case ? — About a year ago the Excise officers entered 
 the premises of Messrs. Mayor and Dove, large spice merchants in Little Distaff 
 Lane, and seized a quantity of ground white pepper, alleging it to be adulterated, and 
 carried it off. I attended the Court of Excise. Professor Graham and Mr. George 
 Phillips, the two witnesses as to the adulteration on the part of the Excise, were first 
 examined, and they swore that the seized pepper contained sago to the amount of 10 
 or 12 per cent., and they produced a few particles like sago in a very small pill-box." 
 [For the other details, see the article Pepper in this Supplement.] 
 
 " 8596. From the advance of chemical science, supposing the Excise Office to have 
 your assistance, or the assistance of other experienced chemists, do you think that, with 
 
256 
 
 TOBACCO. 
 
 all that assistance, they could detect an adulteration that might, with perfect facility, 
 be introduced by chemists? — I would say that adulteration may be made upon tobacco 
 which may defy all the chemists in Europe to find out. 
 
 "8597. And not only chemists, but physiologists? — Yes, and botanists." 
 
 It will be seen, from the vagueness of the results of the several series of experi- 
 ments which I made on the seven samples of tobacco sent to me by the committee, 
 with every possible attention in the short period allowed me, that it is no easy matter 
 to detect adulterations in tobacco ; and a chemist should be extremely cautious in pro- 
 nouncing a decided opinion upon such slender grounds as the professional gentlemen 
 employed by the Excise Board have in many cases done. Supposing a tobacco poor in 
 extractive matter, like the Kentucky, were skilfully imbued with juice of liquorice till 
 it came to the standard of the Virginia, neither Mr. G. Phillips, by his plan of infusion, 
 nor Professor Graham, by that of fermentation, could detect the adulteration. The 
 liquorice juice assimilates with tobacco better even than sugar, but "it is incapable of 
 undergoing the spirituous fermentation." * 
 
 I offer this one example, out of many, merely as a hint to my brother chemists 
 to be somewhat less confident and dogmatical in their decisions. Were the questions 
 of tobacco adulteration referred to one of our law courts in Westminster or Guildhall, 
 the evidence of the chemists for the prosecution would be weighed in a more ticklish 
 balance than that of a provincial justice of the peace, or even of the Honourable Com- 
 missioners of Excise, and it might possibly be found wanting. 
 
 How vexatiously inquisitorial, and how abhorrent from the genius of the British 
 constitution, must the practice of the Excise Board be, when the following regulations 
 are recommended by its most influential functionary ! To question 8005, Mr. George 
 Phillips replies : " I would make the manufacturers responsible for the samples which 
 they gave; for instance, we know very well there are only two tobaccos used for 
 general cutting tobaccos, that is, Kentucky and Virginia ; we know the nature of those, 
 and we very well know what description of tobacco the manufacturer must use to make 
 it answer his purpose. A tobacco which will not yield 45 per cent, of extractive is not 
 fit for him to use. If he sent a sample which should be 35, such as Porto Rico, or got 
 some rubbishing stuff from the sales at the tobacco warehouse, / would not allow that 
 sample to be used, or at any rate to be mixed with any other ; if he used that, he should 
 use that alone ; he should be confined within a range, which experience has proved to 
 be the general range." No choice for taste is to be allowed. Again, to question 8023, he 
 answers : " Sometimes the seizures are made before the tobacco is examined ; sometimes 
 seizures are made afterwards, upon my report that it is adulterated. The officers send 
 a sample up unknown to the manufacturer ; they take a sample unknown to the manu- 
 facturer, and then, after I have examined it, instructions are sent to the supervisor, 
 that any tobacco of that sort that he can find on the manufacturer's premises he should 
 seize. If the tobacco is seized merely upon the examination of the sample, samples 
 taken from the bulk of the seizure are then sent up and examined. I could mention 
 cases where samples have been sent up by the supervisor or other officer, and have been 
 examined ; they have gone and seized, after the lapse of a fortnight, and it has turned 
 out that the tobacco has been pure when it has been examined ; of course that has been 
 returned again." Question 8024. " How small an amount would you report to be 
 adulterated ? — Two per cent." 
 
 Every intelligent reader of the experimental and other evidence detailed in the 
 present article, must perceive the precariousness of decisions based upon an adultei-ation 
 of only 2 per cent., in so complex a substance as tobacco, that adulteration being sworn 
 to in consequence of such unsatisfactory microscopic and chemical researches. What 
 a servile spirit must be engendered among the tributaries to the Excise, when thirteen 
 eminent tobacconists of London could recently petition the House of Commons to 
 aggravate the stringent administration of that tribunal, praying that adulterations de- 
 tected by its officers should be prosecuted more rigorously ; and the efficiency of the 
 law be " further secured by the abolition of compromise, publicity by prosecution in 
 the local courts or otherwise, and the substitution of personal for pecuniary penalties." 
 
 What powerful inducements are held out to Mr. George Phillips and his coadjutors 
 to obtain convictions for adulterations of tobacco, may be inferred from the fact, that 
 " all penalties and seizures are by law divisible in equal parts, between the Crown and 
 the informer ; " 1st, to the person by whom the information was communicated ; 2dly, to 
 the officers by whose instrumentality, and subsequent aid, proceedings for penalties are 
 brought to a successful termination. In all other cases, liberal means of remuneration 
 are placed at the disposal of the Board of Excise. See Memorandum as to rewards fo? 
 information given to the Excise, p. 584., Tobacco Report. 
 
 * Licbig, Chimie Organique, iii. 43. 
 
TORTOISE-SHELL. 
 
 257 
 
 TORTOISE-SHELL is manufactured into various objects, partly by cutting out 
 the shapes, and partly by agglutinating portions of the shell by heat. When the shell 
 has become soft by dipping it in hot water, the edges are in the cleanest possible state, 
 without grease, pressed together with hot flat tongs, and then plunged into cold water, 
 to fix them in their position. The teeth of the larger combs are parted in their heated 
 state, or cut out with a thin frame saw, while the shell, equal in size to two combs, 
 with their teeth interlaced, as in Jig. 166., is bent like an arch in the direction of the 
 
 167 
 
 166 
 
 168 
 
 1 
 
 
 
 r 
 
 
 
 
 ^ tpj 
 
 169 
 
 IlSlfil 
 
 
 
 I il 
 
 
 
 173 
 
 170 
 
 length of the teeth, as in Jig. 167. The shell is then flattened, the points are separated 
 with a narrow chisel or pricker, and the two combs are finished, while flat, with coarse 
 single-cut files and triangular scrapers. They are finally warmed, and bent on the knee 
 over a wooden mould, by means of a strap passed round the foot, just as a shoemaker 
 fixes his last. Smaller combs of horn and tortoise-shell are parted, while flat, by an 
 ingenious machine, with two chisel-formed cutters placed obliquely, so that each cut 
 produces one tooth. See Rogers' comb-cutting machine, Trans. Soc. Arts, vol. xlix. 
 part 2., since improved by Mr. Kelly. In making the frames for eye-glasses, spec- 
 tacles, &c. the apertures for the glasses were formerly cut out to the circular form, with 
 a tool something like a carpenter's centre-bit, or with a crown saw in the lathe. The 
 discs so cut out were used for inlaying in the tops of boxes, &c. This required a piece 
 of shell as large as the front«of the spectacle ; but a piece one third of the size will now 
 suffice, as the eyes are strained or pulled. A long narrow piece is cut out, and two slits 
 are made in it with a saw. The shell is then warmed, the apertures are pulled open, 
 and fastened upon a taper triblet of the appropriate shape ; as illustrated by Jigs. 168, 
 169, and 170. The groove for the edge of the glass is cut with a small circular cutter, 
 or sharp-edged saw, about three eighths or half an inch in diameter ; and the glass is 
 sprung in when the frame is expanded by heat. 
 
 In making tortoise-shell boxes, the round plate of shell is first placed centrally over 
 the edge of the ring, as in Jig. 171. : it is slightly squeezed with the small round edge- 
 block g, and the whole press is then lowered into the boiling water ; after immersion 
 for about half an hour, it is transferred to the bench, and g is pressed entirely down, so 
 as to bend the shell into the shape of a saucer, as at Jig. 172., without cutting or injuring 
 the material ; and the press is then cooled in a water-trough. The same processes are 
 repeated with the die d, which has a rebate turned away to the thickness of the shell, 
 and completes the angle of the box to the section Jig. 173., ready for finishing in the 
 lathe. It is always safer to perform each of these processes at two successive boilings 
 and coolings. Two thin pieces are cemented together by pressure with the die e, and a 
 device may be given by the engraved die / See HoltzapffeVs Turning and Mechanical 
 Manipulation, vol. i. p. 129. 
 
 L 1 
 
258 
 
 VENTILATION. 
 
 TURPENTINE, SPIRITS, ESSENCE, OR OIL OF. Camphen is the new 
 name given by the continental chemists to every ethereous or volatile oil, which is com- 
 posed of 5 atoms of carbon and 8 of hydrogen, and which combines directly with hydro- 
 chloric acid, either into a solid or a liquid compound, resembling camphor. Under this 
 title the following oils are included : — turpentine, citron, or lemon, orange-flower, 
 copaiva, balsam-oil, juniper, cubebs, and pepper. Some add to this last, — the oils of 
 cloves, valerian, and bergamot. As the new patent lamps burn spirits of turpentine, 
 they have been called Camphine. ( See Lamps.) Since that article was printed I have 
 had occasion to test a variety of Camphine lamps during the preceding three months, and 
 I am convinced the patent Vesta lamp of Mr. Young is not merely the best, but it is the 
 only one hitherto made public, which can be used with comfort in closed apartments. 
 It was the first spirit lamp constructed on right principles, keeping in view the peculiar 
 nature of Camphine spirits, and being secured by a correct specification, leaves no room 
 to expect another equally good. In this lamp the burner is completely insulated from 
 the reservoir by a ring of wood, or other non-conducting material, placed between them, 
 and as no metallic tube passes down from the flame into the volatile spirits, they remain 
 cold ; whereas, when such a tube passes down through the reservoir, for the admission 
 of air to the inside of the flame (as in all other Argand lamps), without being insulated 
 from the flame, the spirits become 20 or 30 degrees hotter, so as to emit acrid and 
 offensive fumes. The wick also, which embraces the heated tube becomes dry and 
 resinous, loses its capillary power, coals at the flame, and then sends up smoke with a 
 shower of lamp black. 
 
 The Vesta lamp is free from these defects, and when used with properly rectified 
 spirits, never smokes nor smells ; it may be easily distinguished by the above characters, 
 and by the circumstance of the air passing between the wicks to the interior of the 
 flame. It affords, undoubtedly, the brightest, cleanliest, and most economical light 
 hitherto invented, when supplied with pure spirits free from rosin. I have lighted my 
 drawing-rooms with the Vesta lamp for several evenings successively, without having 
 its wick trimmed or its occasioning the slightest inconvenience. I therefore deem it 
 due to the patentee's ingenuity, as well as to the public welfare, to give this deliberate 
 opinion at a time Avhen the volatile spirits of turpentine are getting into general use, 
 and when, if burned in lamps on the Argand plan, they must create danger. 
 
 Great care must be taken in the choice of the spirits of turpentine as the combustible. 
 As those very generally sold in London contain rosin and other impurities, they are 
 quite unfit for that purpose; but the spirits manufactured by Messrs. John Tall and 
 Co. of Hull, to be had of their agents, Ratcliffe and Co., 103. Hatton Garden, 
 London, answer perfectly. I have subjected these spirits to careful chemical exami- 
 nation, and I find them to be quite pure, and very different indeed from those on 
 common sale here. Their specific gravity is only 0 864 at 62° Fahr., while that of 
 the average London article is from 0*874 to 0*882, the greater density being due to 
 rosin. Messrs. Tail's spirits may be boiled off in a retort without leaving any sensible 
 residuum, and they also boil at a lower degree of heat ; but the best proof of their ex- 
 cellence, in the present point of view, is exhibited in the preceding notice of the Vesta 
 lamp, for it was Messrs. Tail's spirits which were used on that occasion. 
 
 V. 
 
 VENTILATION. There are two general plans in use for at once diffusing heat 
 and renewing the air in extensive buildings, which plans differ essentially in their prin- 
 ciples, modes of action, and effects. The oldest, and what may be called, the vulgar 
 method, consists in planting stoves in the passages or rooms, to give warmth in cold 
 weather, and in constructing large and lofty chimney-stalks, to draw air in hot weather 
 out of the house, by suction, so to speak, whereby fresh air flows in, to maintain, though 
 imperfectly, an equilibrium of pressure. In apartments, thus warmed and ventilated, 
 the atmosphere is necessarily rarer than it is out of doors, while, in cold weather, the 
 external air rushes in at every opening and crevice of door, window, or chimney — the 
 fruitful source of indisposition to the inmates. 
 
 The evils resulting from the stove-heating and air-rarefying system were, a few years 
 ago, investigated by me, in a Paper read before the Royal Society*, and afterwards 
 
 * I had been professionally employed by a Committee of the Officers of the Custom House, to 
 examine the nature of the malaria which "prevailed there, but 1 had no concern in erecting the stoves 
 Which caused it. 
 
VENTILATION. 
 
 259 
 
 published in several scientific and technological journals. It is there said that the 
 observations of Saussure, and other scientific travellers in mountainous regions, demon- 
 strate how difficult and painful it is to make muscular or mental exertions in rarefied 
 air. Even the slight rarefaction of the atmosphere, corresponding to a low state of the 
 barometer, at the level of the sea, is sufficient to occasion languor, lassitude, and un- 
 easiness in persons of delicate nerves ; while the opposite condition of increased pressure 
 as indicated by a high state of the barometer, has a bracing effect upon both body and 
 mind. Thus, we see how ventilation, by the powerful draught of a high chimney-stalk, 
 as it operates by pumping out, exhausting, and attenuating the air, may prove detri- 
 mental to vivacity and health ; and how ventilation, by forcing in air with a fan or a 
 pump, is greatly to be preferred, not only for the reason above assigned, but because it 
 prevents all regurgitation of foul air down the chimneys, an accident sure to happen in 
 the former method. Genial air thrown in by a fan, in the basement story of a building, 
 also prevents the stagnation of vapours from damp and miasmata, which lurk about the 
 foundation of buildings and in sewers, and which are sucked in by the rarefying plan. 
 Many a lordly mansion is rendered hardly tenantable from such a cause, during certain 
 vicissitudes of wind and weather. 
 
 The condensing plan, as executed by the engineers, Messrs. Easton and Amos, at the 
 Reform Club House, consists of a large fan, revolving rapidly in a cylindrical case, and 
 is capable of throwing 11,000 cubic feet of air per minute into a spacious subterranean 
 tunnel, under the basement story. The fan is driven by an elegant steam-engine, 
 worked on the expansion principle, of five horses' power. It is placed in a vault, under 
 the flag-pavement, in front of the building ; and as it moves very smoothly, and burns 
 merely cinders from the house fires, along with some anthracite, it occasions no nuisance 
 of any kind. The steam of condensation of the engine supplies 3 cast-iron chests with 
 the requisite heat for warming the whole of the building. Each of these chests is a 
 cube of 3 feet externally, and is distributed internally into 7 parallel cast-iron cases, 
 each about 3 inches wide, Avhich are separated by parallel alternate spaces, of the same 
 width, for the passage of the air transversely, as it is impelled by the fan. 
 
 Fiy. 1 74. is a transverse vertical section of the steam chest, for heating the air ; fig. 175. 
 is a plan of the same ; and fig. 176, is a perspective view, showing the outside casing, also 
 the pipe a, for admitting the steam, and the stop-cock b, for allowing the condensed 
 water to escape. 
 
 175 176 
 
 174 
 
 This arrangement is most judicious, economising fuel to the utmost degree ; because 
 the steam of condensation which, in a Watt's engine, would be absorbed and carried off 
 by the air-pump, is here turned to good account, in warming the air of ventilation 
 during the winter months. Two hundred weight of fuel suffice for working this steam- 
 engine during twelve hours. It pumps water for household purposes, raises the coals 
 to the several apartments on the upper floors, and drives the fan ventilator. The air, 
 in flowing rapidly through the series of cells, placed alternately between the steam- 
 cases, cannot be scorched, as it is generally with air stoves ; but it is heated only to the 
 genial temperature of from 75° to 85° Fahr., and it thence enters a common chamber 
 of brick- work in the basement story, from which it is let off into a series of distinct 
 flues, governed by dialled valves or registers, whereby it is conducted in regulated 
 quantities to the several apartments of the building. I am of opinion, that it would 
 not be easy to devise a better plan for the purpose of warming and ventilating a large 
 house ; and I am only sorry to observe, that the plan projected by the engineers has 
 been injudiciously counteracted in two particulars. 
 
 The first of these is, that the external air, which supplies the fan, is made to traverse 
 a great heap of coke before it can enter that apparatus, whereby it suffers such friction 
 as materially to obstruct the ventilation of the house. The following experiments, which 
 I made recently upon this point, will place the evil in a proper light : — Having fitted 
 up Dr. Wollaston's differential barometer, as an anemometer, with oil, of specific gravity 
 0-900 in one leg of its syphon, and water of 1*000 in the other, covered with the said oil 
 in the two cisterns at top, I found that the stream of air produced by the fan, in a eer- 
 
 LI 2 
 
260 
 
 VENTILATION. 
 
 tain part of the flue, had a velocity only as the number 8, while the air was drawn 
 through the coke, but that it had a velocity in the same place as the number 1 ] , when- 
 ever the air was freely admitted to the fan by opening a side door. Thus, three- 
 elevenths, both of the ventilating and warming effect of the fan, are lost. I cannot 
 divine any good reason for making the Members of the Reform Club breathe an 
 atmosphere, certainly not improved, but most probably vitiated, by being passed in a 
 moist state through a porous sulphurous carbon, whereby it will tend to generate the 
 two deleterious gases, carbonic oxide and sulphuretted hydrogen, in a greater or less 
 degree. It is vain to allege that these gases may not be discoverable by chemical 
 analysis — can the gaseous matters, which generate cholera, yellow fever, or ague, be 
 detected by chemical re-agents ? No, truly ; yet every one admits the reality of their 
 specific virus. I should propose that the air be transmitted through a large sheet of 
 wire-cloth before it reaches the fan, whereby it would be freed from the grosser par- 
 ticles of soot that pollute the atmosphere of London. The wire-cloth should be brushed 
 every morning. 
 
 The second particular, which counteracts in some measure the good effects of the fan 
 in steam ventilation, is the huge stove placed in the top story of the building. This 
 potent furnace, consuming, when in action, 3 cwt. of coals per day, tends to draw down 
 foul air, for its own supply, from the chimneys of the adjoining ropms, and thus to im- 
 pede the upward current created by the fan. I have measurejl, by Dr. Wollaston's 
 differential barometer, the ventilating influence of the said furnace stove, and find it to 
 be perfectly insignificant, — nay, most absurdly so, — when compared with the fan, as 
 to the quantity of fuel which each requires per day. The rarefaction of air in the stove 
 chamber, in reference to the external air, was indicated by a quarter of an inch diffe- 
 rence of level in the legs of the oil and water syphon, and this when the door of the 
 stove-room was shut, as it usually is ; the tube of the differential barometer being 
 inserted in a hole in the door. The fan indicates a ventilating force equal to 2 inches 
 of the water syphon, which is 20 inches of the above oil and water syphon, and there- 
 fore 80 times greater than that of the stove furnace ; so that, taking into view the 
 smaller quantity of fuel which the fan requires, the advantage in ventilation, in favour 
 of the fan, is the enormous ratio of 120 to 1, at the lowest estimate. The said stove, 
 in the attic, seems to me to be not only futile, but dangerous. It is a huge rectangular 
 cast-iron chest, having a large hopper in front, kept full of coals, and it is contracted 
 above into a round pipe, which discharges the burnt air and smoke into a series of hori- 
 zontal pipes of cast-iron, about 4 inches diameter, which traverse the room under the 
 ceiling, and terminate in a brick chimney. In consequence of this obstruction, the 
 draught through the furnace is so feeble, that no rush of air can be perceived in its ash- 
 pit, even when this is contracted to an area of 6 inches square ; — nay, when the ash-pit 
 was momentarily luted with bricks and clay, and the tube of the differential barometer 
 was introduced a little way under the grate, the level of the oil and water syphon 
 in that instrument was displaced by no more than one-tenth of an inch, which is 
 only one-hundredth of an inch of water, — a most impotent effect under a daily con- 
 sumption of 3 cwt. of coals. In fact, this stove may be fitly styled an incendiary coal 
 devourer, as it has already set fire to the house ; and though now laid upon a new floor 
 of iron rafters and stone flags, it still offers so much danger from its outlet iron pipes, 
 should they become ignited from the combustion of charcoal deposited in them, that I 
 think no premium of insurance adequate to cover the imminent risk of fire. The stove 
 being, therefore, a superfluous and dangerous nuisance, should be turned out of doors 
 as speedily as possible. Its total cost, with that of its fellow in the basement story, 
 cannot be much less than the cost of the steam-engine, with all its truly effectual warm- 
 ing and ventilating appurtenances. 
 
 I take leave to observe, that the system of heating and ventilating apparatus, con- 
 structed by Messrs. Easton and Amos, in the Reform Club House, offers one striking 
 and peculiar advantage. It may be modified at little expense, so as to become the 
 ready means of introducing, during the sultriest dog-days, refreshing currents of air, at 
 a temperature of 10, 20, 30, or even 40 degrees under that of the atmosphere. An ap- 
 paratus of this nature, attached to the Houses of Parliament and Courts of Law, would 
 prove an inestimable blessing to our legislators, lawyers, judges, and juries. Of such 
 cool air a very gentle stream would suffice to make the most crowded apartments com- 
 fortable, without endangering the health of their inmates with gusts of wind through 
 the doors, windows, and floors. 
 
 It is lamentable to reflect how little has been done for the well-being of the sentient 
 and breathing functions of man in the public buildings of the metropolis, notwithstand- 
 ing our boasted march of intellect and diffusion of useful knowledge. Almost all our 
 churches are filled on Sundays with stove-roasted air ; and even the House of Commons 
 has its atmosphere exhausted by the suction of a huge chimney stalk, with a furnace 
 equal, it is said, to that of a 40 horse steam boiler. To gentlemen plunged" in air so 
 
VENTILATION. 
 
 261 
 
 attenuated, condensation of thought and terseness of expression can hardly be the order 
 of the day. 
 
 Nearly seven yeaus have elapsed since I endeavoured to point public attention to this 
 important subject in the following terms: — " Our legislators, when bewailing, not 
 long ago, the fate of their fellow-creatures, doomed to breathe the polluted air of a fac- 
 tory, were little aware how superior the system of ventilation adopted in many cotton 
 mills was to that employed for their own comfort in either House of Parliament. The 
 engineers of Manchester do not, like those of the metropolis, trust for a sufficient supply 
 of fresh air into any crowded hall, to currents physically created in the atmosphere by 
 the difference of temperature excited by chimney draughts, because they know them to 
 be ineffectual to remove, with requisite rapidity, the dense carbonic acid gas generated 
 by many hundred powerful lungs."* At page 382. of the work just quoted, there is 
 an exact drawing and description of the factory ventilating fan. 
 
 On the 6th of June, 1836, I took occasion again, in a paper read before the Royal 
 Society, upon the subject of the malaria which then prevailed in the Custom House, to 
 investigate the principles of ventilation by the fan, and to demonstrate, by a numerous 
 train of experiments, the great preference due to it, as to effect, economy, and comfort, 
 over chimney-draught ventilation. Yet at this very time, the latter most objectionable 
 plan was in progress of construction, upon a colossal scale, for the House of Commons. 
 About the same period, however, the late ingenious Mr. Oldham, engineer of the Bank 
 of England, mounted a mechanical ventilator and steam-chest heater, for supplying a 
 copious current of warm air to the rooms of the engraving and printing departments of 
 that establishment. Instead of a fan, Mr. Oldham employed a large pump to force the 
 air through the alternate cells of his steam chest. He had introduced a similar system 
 into the Bank of Ireland about ten years before, which is now in full action. 
 
 About two years ago, Messrs. Easton and Amos were employed to ventilate the 
 letter carriers' and inland office departments of the General Post Office, of which the 
 atmosphere was rendered not only uncomfortable but insalubrious, by the numerous 
 gas lights required there in the evenings. This task has been executed to the entire 
 satisfaction of their employers, by means of fans driven by steam engine power. The 
 said engineers made, about the same time, a set of machinery similar to that erected at 
 the Bank of England, for warming and ventilating the Bank of Vienna. They are 
 justly entitled to the credit of having been the first to execute, in all its bearings, the 
 system of heating and ventilating buildings, having special respect to the health of their 
 inmates, which I urged upon the public mind many years ago. 
 
 As fans of sufficient size, driven by steam power with sufficient velocity to warm in 
 winter, and ventilate at all times, the most extensive buildings, may be erected upon 
 the principles above described, without causing any nuisance from smoke, it is to be 
 hoped that the Chapel of Henry VII. will not be desecrated by having a factory 
 Vesuvius reared in its classical precincts, and that the noble pile of architecture of the 
 new Houses of Parliament will not be disfigured with such a foul phenomenon. 
 
 The cheering and bracing action of condensed air, and the opposite effects of rarefied 
 air upon human beings, formed the subject of several fine physiological experiments, 
 made a few years ago by M. Junot, and described by him in the 9th volume of the 
 Archives Generates de Medecine — " When a person is placed," says he, " in condensed 
 air, he breathes with a new facility ; he feels as if the capacity of his lungs was en- 
 larged ; his respirations become deeper and less frequent ; he experiences, in the course 
 of a short time, an agreeable glow in his chest, as if the pulmonary cells were becoming 
 dilated with an elastic spirit, while the whole frame receives, at each inspiration, fresh 
 vital impulsion. The functions of the brain get excited, the imagination becomes 
 vivid, and the ideas flow with a delightful facility ; digestion is rendered more active, as 
 after gentle exercise in the air, because the secretory organs participate immediately in 
 the increased energy of the arterial system, and there is therefore no thirst." 
 
 In rarefied air the effects on the living functions are just the reverse. The breathing 
 is difficult, feeble, frequent, and terminates in an asthmatic paroxysm ; the pulse is 
 quick and most compressible ; haemorrhages often occur, with a tendency to fainting ; 
 the secretions are scanty or totally suppressed, and at length apathy supervenes. 
 
 These striking results obtained on one individual at a time, with a small experimental 
 apparatus, have been recently reproduced, on a working scale, with many persons at 
 once enclosed in a mining shaft, encased with strong tubbing, formed of a series of 
 large sheet-iron cylinders, riveted together, and sunk to a great depth through the bed 
 of the river Loire, near Languin. The seams of coal, in this district of France, lie 
 under a stratum of quicksand, from 18 to 20 metres thick, (20 to 22 yards,) and they 
 had been found to be inaccessible by all the ordinary modes of mining previously prac- 
 tised. The obstacle had been regarded to be so perfectly insurmountable, that every 
 
 * Philosophy of Manufactures, p 330. published by Charles Knight. — London, 1835. 
 
262 
 
 WATERS, MINERAL. 
 
 portion of the great coal basin, that extends under these alluvial deposits, though well 
 known for centuries, had remained untouched. To endeavour, by the usual workings, 
 to penetrate through these semi-fluid quicksands, which communicate with the waters 
 of the Loire, was, in fact, nothing less than to try to sink a shaft in that river, or to 
 drain the river itself. But this difficulty has been successfully grappled with, through 
 the resources of science, boldly applied by M. Triger, an able civil engineer. 
 
 By means of the above frame of iron tubbing, furnished with an air-tight ante- 
 chamber at its top, he has contrived to keep his workmen immersed in air, sufficiently 
 condensed by forcing-pumps, to repel the water from the bottom of the iron cylinders, 
 and thereby to enable them to excavate the gravel and stones to a great depth. The 
 compartment at top has a man-hole door in its cover, and another in its floor. The 
 men, after being introduced into it, shut the door over their heads, and then turn the 
 stop-cock upon a pipe, in connection with the condensed air in the under shaft. An 
 equilibrium of pressure is soon established in the ante-chamber, by the influx of the 
 dense air from below, whereby the man-hole door in the floor may be readily opened, 
 to allow the men to descend. Here they work in air, maintained at a pressure of three 
 atmospheres, by the incessant action of leathern valved pumps, driven by a steam engine. 
 While the dense air thus drives the waters of the quicksand, communicating with the 
 Loire, out of the shaft, it infuses at the same time such energy into the miners, that 
 they can easily excavate double the work without fatigue which they could do in the 
 open air. Upon many of them the first sensations are painful, especially upon the ears 
 and eyes, but ere long they get quite reconciled to the bracing element. Old asthmatic 
 men become here effective operatives ; deaf persons recover their hearing, while others 
 are sensible to the slightest whisper. The latter phenomenon proceeds from the 
 stronger pulses of the dense air upon the membrane of the drum of the ear. 
 
 Much annoyance was at first experienced from the rapid combustion of the candles, 
 but this was obviated by the substitution of flax for cotton thread in the wicks. The 
 temperature of the air is raised a few degrees by the condensation. 
 
 Men, who descend to considerable depths in diving bells, experience an augmentation 
 of muscular energy, similar to that above described. They thereby acquire the power 
 of bending over their knees strong bars of iron, which they would find quite inflexible 
 by their utmost efforts when drawn up to the surface. 
 
 These curious facts clearly illustrate and strongly enforce the propriety of ventilating 
 apartments by means of condensed air, and not by air rarefied with large chimney 
 drafts, as has been hitherto most injudiciously, wastefully, and filthily done, in too many 
 cases. 
 
 VERMICELLI is made with most advantage from the flour of southern countries, 
 which is richest in gluten. It may also be made from our ordinary flour, provided an 
 addition of gluten be made to the flour paste. Vermicelli prepared from ordinary 
 flour is apt to melt into a paste when boiled in soups. It may, however, be well made 
 economically by the following prescription : — 
 
 Vermicelli or Naples flour - - - 21 lbs. 
 
 White potato flour - - -14 — 
 
 Boiling water - - - - 12 — 
 
 Total - - 47 lbs. 
 
 Affording 45 lbs. of dough, and 30 of dry vermicelli. With gluten, made from common 
 
 flour, the proportions are : — 
 
 Flour as above - - - - SO lbs. 
 
 Fresh gluten - - - 10 — 
 
 Water - - - - 7 — 
 
 Total - - 47 lbs. 
 
 Affording 30 lbs. of dry vermicelli or macaroni. 
 
 w. 
 
 WATERS, MINERAL. The following Tables exhibit the Nature and Com- 
 position of the most celebrated Mineral Waters of Germany, according to the best 
 Analyses. The Symbol N denotes Nitrogen or Azote; O, Oxygen; CO 2 , Carbonic 
 Acid; SH, Sulphuretted Hydrogen. Therm.; cent, scale; if not, R. for Reaumur. 
 
II 
 
 3s 8 
 
 si 
 
 •8 a 
 
 So © to <o 
 
 3° j? 
 
 fee 6 
 
 a* .| 
 
 6 S^h H 
 
 ^6 $ :■: -2 
 
 13 
 
 » U 00 00 00 73 © 
 
 to O 00 
 
 6 to <N 
 
 r.-2 -a «o «s 
 
 C -Sto 
 £„°6 
 
 £g 
 §1 
 
 ' £ §3 
 
 5 3 B 
 
 6 ^ 
 
 8 8 
 
 to fc. 
 
 oo US 
 
 6 6 
 
 o? 
 
 C40 
 
 6i 6 o £ £ 
 
 9fl 
 
 CO CO CO CO CC CO CO 
 
 It 
 
 Plllll^ll^fp flip I I I 
 
 S3 03N £ £nO &O0 Ph « Q — S 3 g g ST 3 
 
 f • " " " « 'eta 52. £"£• "«g — 
 
 111 I m«% HI jg-j alii i 
 
 Els 
 
 2 - 
 
 lis 
 
ill 
 
 H > 
 
 33 s 
 
 fSf|| If "g gg||| if s.| 1 
 
 SOjS «_e? tag ds©^ 3 E-SC 
 
 fill' 
 
 71 © 
 
 0* O !K c« 
 
 — X — 
 
 I3l|l|2.#6 
 
 tOGN 
 ©O 
 
 66 
 
 O -f 
 
 66 
 
 6E 
 
 ll 
 
 II!? 
 
 Q ~ ~, Q Q 
 
 i»8 
 
 : - '© 
 
 Pa 
 
 C -3 
 
 if ©S 
 
 ;s If 
 
 © 
 
 S3 
 
 © O i£"5 
 
 © = 5'3 
 66 g ° 
 
 § 2 
 
 a 
 
 CM p 
 
 1T 1 
 
 1 
 
 131*217 
 
 100 
 41-65 
 
 16-62 
 26-0 
 
 ■P 9 o 
 
 22-07 
 40-85 | 
 
 ^ La 
 
 0-505 
 ~ 100 
 
 if ; 
 
 a> to , , 
 6 © 
 
 II II . . 
 
 1 I • 
 • 1 I 
 
 ■ ■ 
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 ~4 
 
 2i© 
 
 i~5 "-i jj . o go I aj 
 .« 05 to 1 o o co 1 <o I °e i" I »o 1 05 
 
 
 1* 
 
 1-00 
 0- 
 
 O L O <! OS OO 1 © ° © o 
 
 9 oo ? in t.9 r 31 ® '? °- ? » 
 
 00-1 
 00. 1 
 
 S c — 
 
 2 3i = 
 111 
 
 fib 
 
 \m [jeqo .9 li a .3 
 
 3 = -s|g § is #& *-3 
 
 .0.2 -5 sS' .g 3E S.a 
 
 Q a 1-3 PQ S3 05 
 
 1e? 
 ►as 
 
 ^ fa-?.-? 
 
 1-2 
 
 O 3 -2 
 
 Mm 
 
S 3*3 H-a >fa 
 
 o .o to r; >- 
 
 CbS«S of o 
 
 Jo g 
 i a5 
 
 '5 = °- 1 
 
 c 2 o 
 
 S3 
 
 .511 .1-1 
 
 3- E 
 
 k ai <! « m 
 
 r.E i x 
 oca 
 
 i S .t; S -s a s 
 
 <=>! 
 
 311 
 
 5^ 
 
 1 
 
 ns<3 
 
 - la} B3 
 
 S3 
 
 M I 0 
 
 8 2 
 
 9 I 
 
 "is 
 
 •Si §g 
 5 3? £ 3 
 
 2~ S 
 
 PS: C 
 i £. tL s 
 
M -i .ti to 
 t-o to 
 
 o+ a, * a 
 
 .■SOB 
 
 * ssi 
 
 £B3 
 
 00 03 & 
 
 ©■ £2 
 
 6 66 
 
 S3 
 66 
 
 •8 3 
 
 S 5 
 
 fa ii 
 
 MS ig| 
 
 Si c"2 "Sjsi 
 
 filij Si 
 
 S — 'C 
 
•£ £ 8 a 
 
 in 
 
 W 2 
 6a 
 
 t~ * o o 
 
 gg 6a °S§^I§3i 
 
 .1 »|s?l§ 6 . 
 
 <3 Pi X Pi 02 ^{/J Pi 2< 
 
 2 ■= = " S r« 
 
 I 10 wSI 0) 
 
 s 4 
 
 „ 0660 « — r v ~"'2 _ 
 
 . fl CO . ««l . o . SO 
 
 3 .c ao-a jjj 2 £? 36 
 
 CO Ol, cfJK&H W X 
 
 9 2 
 
 OtN 
 
 1 .6 6 
 
 2 § ™" i 
 ■Nil 
 
 Sb g g 
 
 >2«i 
 
 3 2 S 
 6 Ai 
 
 ■sli 
 
 fill 
 
 CO. 
 
 s If 
 
 6 00 
 
 cc a 
 
 6b 
 
 O 3 
 . u 
 
 X 
 
 111 
 
 O^ 1 
 
 ?! 
 
 cS 3, ,o5 
 
 O CN o 
 
 >o o I 
 
 n c I to 
 
 2 
 
 i II I 
 
 a — S "S M 
 •3 c2 2cco 
 
 a"S 
 
 III 
 
 *7 
 
 M 
 
 Hi 
 
 S efl 
 
- a 
 
 so 
 
 11 
 
 5 8 
 
 ""oo 
 
 ■g-sgi Sg" £3 £8 8 8 « | g - 
 
 K20 —c 
 
 >h6 
 
 66ri 
 
 II I 
 
 □5 pj 
 
 I ft ' 
 
 I f « . 
 
 • 8 
 
 if 8F 
 
 Authors. 
 
 
 
 Bluhm. 
 Schmeisser 
 Becker. 
 
 PfafF. 
 
 Hermb- 
 stadt. 
 
 
 1 
 
 o> ■? * 
 
 Other Matters, wit 
 Total. 
 
 Veget. soil, 1-0 - - 
 Extractive, 0-66 
 Carb. of Lime, 0-4 - 
 Resinous matter, 0-5 
 Carb. of Lime and 
 
 Magnesia, 4" 204 
 Red Carb. of 1 
 
 Iron, 0-35 - - 
 
 Silica, 0 200 -J 
 
 
 c . 
 
 «a 
 
 ■ 1 OO w 
 
 phuric S 
 
 Lime. 
 
 8-000 
 
 6- 0 
 
 7- 0 
 
 3-5 
 10-600 
 
 "3 
 
 '75 
 
 Soda. 
 
 1- 333 
 
 2- 0 
 
 3- 782 
 
 
 Magne- 
 sia. 
 
 CO oo 
 
 ^yoo o ft 
 
 iriatic Se 
 
 Lime, 
 
 jr. _ 
 1-0 
 
 Traces 
 
 of 
 Potash. 
 
 5-075 
 
 M 
 
 1 
 
 33 
 
 C§o8 o gol 
 x oi di-io 
 
 ►> — 1 - 05 O Pl, 
 
 c 
 
 3 
 
 a 
 
 
 NCOCOCO CO CO 
 
 Places. 
 
 Norderney 
 Cu shaven 
 Fohr 
 Duster- 
 brock 
 
 Dobberan, 
 Salzquelle - 
 
 bonic Acid, 
 572 cub. in. 
 e, 0-832 
 cub. in. 
 
 
 < , Bwg 
 
 
 3 S 
 
 <N CN 
 
 fe^S 1 s 
 
 3xides. 
 
 Silica. | 
 
 21-36 
 and with 
 Carbon. 
 1 50-25 
 
 92-25 
 Sand. 
 
 128-139 
 
 
 Iron- 
 oxide. 
 
 T3-0 cal- 
 < careous 
 
 [earth. 
 3-45 with 
 
 Mangan. 
 3-0 
 
 9-539 
 
 »9 
 
 — O 
 
 c ^ 
 3 S 
 
 or. 
 
 parts. 
 
 100 
 
 100 
 
 1000 
 240 
 2128 
 
 Authors. 
 
 Westrumb. 
 Witting. - 
 Buchholz - 
 Schenk 
 Steinmann. 
 
 Places. 
 
 Eilsen - 
 
 Fiestel - 
 
 Giinthersbad 
 Oestr. Baden 
 Marienbad - 
 
270 
 
 WHALEBONE. 
 
 WEAVING OF HAIR CLOTH. In addition to the description of this art, 
 under " Hair" in the Dictionary, I shall give here a short notice of the best kind of 
 shuttle for weaving hair. Fig. 177. shows in plan A, and in longitudinal section B, a 
 
 . c c 
 
 shuttle which differs from that of the common cloth weaver only In not having a pirn 
 enclosed in the body of the box-wood, but merely an iron trap a, which turns in the 
 middle upon the pin b. This trap-piece is pressed up at the one end, by the action of 
 the spring c, so as to bear with its other end upon the cleft of the iron plate d, which 
 is intended to hold fast the ends of the hair-weft : d and c together are called the jaw 
 or mouth, whence the popular name of this shuttle. The workman opens this jaw 
 by the pressure of his thumb upon the spring end of the trap a, introduces with the 
 other hand one or more hairs (according to the description of hair cloth) into the 
 mouth, and removing his thumb, lets the hair be seized by the force of the spring. 
 The hairs having one end thus made fast are passed across the warp by the passage of 
 the shuttle, which is received at the other end by the weaver's left hand. The friction 
 rollers, x, x, are like those of fly-shuttles, but are used merely for convenience, as the 
 shuttle cannot be thrown swiftly from side to side. The hand which receives the 
 shuttle opens at the same time the trap, in order to insert another hair, after the 
 preceding has been drawn through the warp on both sides and secured to the list. 
 A child attends to count and stretch the hairs. This assistant may, however, be dis- 
 pensed Avith by means of the following implement, represented in Jig. 178. C, C, is 
 the view of it from above, or the plan ; D, is a side view ; E, a longitudinal section, 
 and F, an oblique section across. The chief part consists in a wooden groove, or 
 chamfered slip of wood, open above, and rounded on the sides. It is about twenty-one 
 inches in length, about as long nearly as the web is broad, therefore a little shorter 
 than the horse-hairs inserted in it, which project about an inch beyond it at each end. 
 They are herein pressed down by elastic slips e, of Indian rubber, so that the others 
 remain, when one or more are drawn out by the ends. The ends of the grooves are 
 flat where the Indian rubber spring exerts its pressure, as shown by the dotted line at 
 F. The spring is formed by cutting out a double piece from the curvature of the 
 neck of a caoutchouc bottle or flask, fastening the one end of the piece by a wire 
 staple in the groove of the shuttle, whereby the other end, which alone can yield, 
 presses upon the inlaid hairs. Wire staples like / (in the section E) are passed 
 obliquely through two places of the groove or gutter, to prevent the hairs from 
 springing up in the middle of the shuttle, which is suitably charged with them. The 
 workman shoves the tool across the opened warp with the one hand, seizes with the 
 other the requisite number of hairs by the projecting ends, and holds them fast, while he 
 draws the shuttle once more through the warp. The remaining hairs are retained in 
 the groove by the springs, and only those for the single decussation remain in the web, 
 to be secured to the list on either side. A weaver with this tool can turn out a double 
 length of cloth of what he could do with the mouth-shuttle. 
 
 WHALEBONE. A patent was granted to Mr. Laurence Kortright in March 1841, 
 for improvements in the treatment of whalebone, which consist in compressing the 
 strips in width to increase their thickness, so as to render the material applicable for 
 forming walking-sticks, whip handles, parasol and umbrella sticks, ramrods, archery 
 bows, &c. He accomplishes this purpose by bending the strips together, introducing 
 them into a steam chest, thereby softening them, and in that state compressing them 
 into a compact mass by appropriate machinery ; for a description, with figures, of 
 which, see Newton's Journal, C.S. xxi. 444. 
 
WHITE LEAD. 
 
 271 
 
 WHITE LEAD. Mr. Thomas Richardson, of Newcastle, one of the most dis- 
 tinguished chemists of Liebig's school, obtained a patent in December 1839, for a 
 preparation of sulphate of lead, applicable to some of the purposes to which the carbo- 
 nate is applied. His plan is to put 56 pounds of flake litharge into a tub, to mix it Avith 
 one pound of acetic acid (and water) of specific gravity 1 -046, and to agitate the mixture 
 till the oxide of lead becomes an acetate. But whenever this change is partially effected, 
 he pours into the tub, through a pipe, sulphuric acid of specific gravity 1*5975, at the 
 rate of about 1 pound per minute, until a sufficient quantity of sulphuric acid has 
 been added to convert all the lead into a sulphate ; being about 20 parts of acid to 112 
 of the litharge. The sulphate is afterwards washed and dried in stoves for the market. 
 I have examined the particles of this white lead with a good achromatic microscope, 
 and found them to be semi-crystalline, and semi-transparent, like all the varieties of 
 carbonate precipitated from saline solutions of the metal. 
 
 Mr. Leigh, surgeon in Manchester, prepares his patent white lead, by precipitating 
 a carbonate from a solution of the chloride of the metal by means of carbonate of 
 ammonia. On this process, in a commercial point of view, no remarks need be made. 
 In Liebig and Woehler's Annalen for May 1843, Chr. Link has communicated his 
 investigation of two sorts of lead, prepared in the Dutch way, by the slow action of 
 vinegar and carbonic acid upon metallic lead, under the heat of fermenting horse-dung. 
 The one sort was manufactured by Sprenger, the other by Klagenfurth of Krems. 
 He also examined 3 specimens of the Offenbach white lead. They all agreed in com- 
 position ; affording 11*29 per cent, of carbonic acid, and 2*23 of water; correspond- 
 ing to the formula, 2 (PbO, C0 2 )+PbO, H 2 0; that is, in words, 2 atoms of 
 carbonate of lead with 1 atom of oxide and 1 atom of water — in round numbers, 
 thus, 2 x 134+ 112 + 9. 
 
 Mulder observed specimens of white lead, of different atomic proportions of car- 
 bonate, oxide and water from the above, and discovered that the quality improved as the 
 carbonate increased. The white lead by the Dutch process, as made by Messrs. Blackett 
 of Newcastle, is certainly superior as a covering oil pigment to all others. Its particles 
 are amorphous and opaque. 
 
 A patent was granted to Mr. Hugh Lee Pattinson in September 1 841, for improvements 
 in the manufacture of white lead, &c. This invention consists in dissolving carbonate 
 of magnesia in water impregnated with carbonic acid gas, by acting upon magnesian 
 limestone, or other earthy substances containing magnesia in a soluble form, or upon 
 rough hydrate of magnesia in the mode hereafter described, and in applying this solu- 
 tion to the manufacture of magnesia and its salts, and to the precipitation of carbonate 
 of lead from any of the soluble salts of lead, but particularly the chloride of lead ; in 
 which latter case the carbonate of lead, so precipitated, is triturated with a solution of 
 caustic potash or soda, by which a small quantity of chloride of lead contained in it 
 is converted into hydrated oxide of lead, and the whole rendered similar in composition 
 to the best white lead of commerce. The manner in which these improvements are 
 carried into effect is thus described by the patentee : — I take magnesian limestone, 
 which is well known to be a mixture of carbonate of lime and carbonate of magnesia, 
 in proportions varying at different localities; and on this account I am careful to 
 procure it from places where the stone is rich in magnesia. This I reduce to powder, 
 and sift it through a sieve of forty or fifty apertures to the linear inch. I then heat it 
 red-hot, in an iron retort or reverberatory furnace, for two or three hours, when, the 
 carbonic acid being expelled from the carbonate of magnesia, but not from the car- 
 bonate of lime, I withdraw the whole from the retort or furnace, and suffer it to cool. 
 The magnesia contained in the limestone is now soluble in water impregnated with 
 carbonic acid gas, and to dissolve it I proceed as follows : — I am provided with an 
 iron cylinder, lined with lead, which may be of any convenient size, say 4 ft. long by 
 21ft. in diameter; it is furnished with a safety-valve and an agitator, which latter 
 may be an axis in the centre of the cylinder, with arms reaching nearly to the circum- 
 ference, all made of iron and covered with lead. The cylinder is placed horizontally, 
 and one extremity of this axis is supported within it by a proper carriage, the other 
 extremity being prolonged, and passing through a stuffing-box at the other end of the 
 cylinder, so that the agitator may be turned round by applying manual or other power 
 to its projecting end. A pipe, leading from a force-pump, is connected with the under 
 side of the cylinder, through which carbonic acid gas may be forced from a gasometer 
 in communication with the pump, and a mercurial gauge is attached, to show at all 
 times the amount of pressure within the cylinder, independently of the safety-valve. 
 Into a cylinder of the size given I introduce from 100 to 120 lbs. of the calcined lime- 
 stone with a quantity of pure water, nearly filling the cylinder ; I then pump in car- 
 bonic acid gas, constantly turning the agitator, and forcing in more and more gas, till 
 absorption ceases, under a pressure of five atmospheres. I suffer it to stand in'this 
 condition three or four hours, and then run off the contents of the cylinder into a 
 
272 
 
 WHITE LEAD. 
 
 cistern, and allow it to settle. The clear liquor is now a solution of carbonate of 
 magnesia in water impregnated with carbonic acid gas, or, as I shall hereafter call it, 
 a solution of bicarbonate of magnesia, having a specific gravity of about 1 "028, and 
 containing about 1 600 grains of carbonate of magnesia to the imperial gallon. 
 
 I consider it the best mode of obtaining a solution of bicarbonate of magnesia from 
 magnesian limestone, to operate upon the limestone after being calcined at a red heat 
 in the way described ; but the process may be varied by using in the cylinder the 
 mixed hydrates of lime and magnesia, obtained by completely burning magnesian 
 limestone in a kiln, as commonly practised, and slaking it with water in the usual 
 manner ; or, to lessen the expenditure of carbonic acid gas, the mixed hydrates may 
 be exposed to the air a few weeks till the lime has become less caustic by the absorp- 
 tion of carbonic acid from the atmosphere. Or the mixed hydrates may be treated 
 with water, as practised by some manufacturers of Epsom salts, till the lime is wholly 
 or principally removed ; after which the residual rough hydrate of magnesia may be 
 acted upon in the cylinder, as described ; or hydrate of magnesia may be prepared for 
 solution in the cylinder, by dissolving magnesian limestone in hydrochloric acid, and 
 treating the solution, or a solution of chloride of magnesium, obtained from sea-water 
 by salt-makers in the form of bittern, with its equivalent quantity of hydrate of lime, or 
 of .the mixed hydrates of lime and magnesia, obtained by completely burning magnesian 
 limestone, and slaking it as above. When I use this solution of bicarbonate of magnesia 
 for the purpose of preparing magnesia and its salts, 1 evaporate it to dryness, by which a 
 pure carbonate of magnesia is at once obtained, without the necessity of using a carbonated 
 alkali, as in the old process ; and from this I prepare pure magnesia by calcination in the 
 usual manner; or, instead of boiling to dryness, I merely heat the solution for some time 
 to the boiling point, by which the excess of carbonic acid is partly driven off, and pure 
 carbonate of magnesia is precipitated, which may then be collected, and dried in the 
 same way as if precipitated by a carbonated alkali. If I require sulphate of magnesia, 
 I neutralise the solution of bicarbonate of magnesia with sulphuric acid, boil down, 
 and crystallise ; or I mix the solution with its equivalent quantity of sulphate of iron, 
 dissolved in water, heated to the boiling point, and then suffer the precipitated car- 
 bonate of iron to subside ; after which I decant the clear solution of sulphate of mag- 
 nesia, boil down, and crystallise as before. When using this solution of bicarbonate 
 of magnesia for the purpose of preparing carbonate of lead, I make a saturated solution 
 of chloride of lead in water, which, at the temperature of 50° or 60° Fahr., has a specific 
 gravity of about 1*008, and consists of 1 part of chloride of lead dissolved in 126 parts 
 of water. I then mix the two solutions together, when carbonate of lead is imme- 
 diately precipitated; but in this operation I find it necessary to use certain precautions, 
 otherwise a considerable quantity of chloride of lead is carried down along with the 
 carbonate. These precautions are, first, to use an excess of the solution of magnesia, 
 and secondly, to mix the two solutions together as rapidly as possible. As to the 
 first, when using a magnesian solution, containing 1600 grs. of carbonate of magnesia 
 per imperial gallon, with a solution of chloride of lead saturated at 55° or 60° Fahr., 
 1 measure of the former to 8i of the latter is a proper proportion ; in which case there 
 is an excess of carbonate of magnesia employed, amounting to about an eighth of the 
 total quantity contained in the solution. When either one or both the solutions vary 
 in strength, the proportions in which they are to be mixed must be determined by 
 preliminary trials. It is not, however, necessary to be very exact, provided there is 
 always an excess of carbonate of magnesia amounting to from one-eighth to one- 
 twelfth of the total quantity employed. If the excess is greater than one-eighth no 
 injury will result, except the unnecessary expenditure of the magnesian solution. 
 As to the second precaution, of mixing the two solutions rapidly together, it may be 
 accomplished variously; but I have found it a good method to run them in two 
 streams, properly regulated in quantity, into a small cistern, in which they are to be 
 rapidly blended together by brisk stirring, before passing out, through a hole in the 
 bottom, to a large cistern or tank, where the precipitate finally settles. The pre- 
 cipitate thus obtained is to be collected, washed and dried in the usual manner. 
 It is a carbonate of lead, very nearly pure, and suitable for most purposes ; but it 
 always contains a small portion of chloride of lead, seldom less than from 1 to 2 
 per cent., the presence of which, even in so small a quantity, is somewhat injurious 
 to the colour and body of the white lead. I decompose this chloride, and 
 convert it into a hydrated oxide of lead by grinding the dry precipitate with a 
 solution of caustic alkali, in a mill similar to the ordinary mill used in grinding white 
 lead with oil, adding just so much of the ley as may be required to convert the pre- 
 cipitate into a soft paste. I allow this paste to lie a few days, after which, the chloride 
 of lead being entirely, or almost entirely decomposed, I wash out the alkaline chloride 
 formed by the reaction, and obtain a white lead, similar in composition to the best 
 white lead of commerce. I prepare the caustic alkaline ley by boiling together, in a 
 
WOOD PAVING. 
 
 273 
 
 leaden vessel, for an hour or two, 1 part by weight of dry and recently-slaked lime, 
 2 parts of crystallised carbonate of soda (which, being cheaper than carbonate of 
 potash, I prefer) and 8 parts of water. The clear and colourless caustic ley, obtained 
 after subsidence, will have a specific gravity of about 1 '090, and, when drawn off from 
 the sediment, must be kept in a close vessel for use. 
 
 WINES. In a case tried before the Court of Exchequer, at the instance of the 
 Board of Customs, in December 1843, of an attempt to obtain the drawback upon a 
 large quantity of damaged Claret offered for exportation, I had observed, in my examin- 
 ation of the wine, that on the addition to it of water of ammonia to super-saturate its 
 acidity, a large flocculent precipitate of decomposed gluten fell, and the supernatant 
 liquor lost its ruby colour, and became yellow-brown. I have tried sound samples of 
 genuine claret, very old, as well as new, by the same test, and I have found the ruby 
 colour to remain but little impaired ; contrary to the allegation of the chemist of the 
 defendants in the lawsuit. The wine was declared by the verdict of a jury and the 
 decision of the judge to be unworthy of being admitted for drawback, and therefore 
 forfeited to the Crown. 
 
 WINES, BRITISH, are made either from infusions of dried grapes (raisins) or from 
 the juices of native fruits, properly fermented. These wines are called sweets in the 
 language of the Excise, under whose superintendence they were placed till 1834, when 
 the duties upon them were repealed, as onerous to the trade and unproductive to the 
 revenue. The raisins called Lexias are said to produce a dry flavoured v/ine ; the 
 Denias a sweet wine ; the Black Smyrnas a strong-bodied wine, and the red Smyrnas 
 and Valencias a rich and full wine. The early spring months are the fittest time for 
 the wine manufacture. The masses of raisins, on being taken out of the packages, are 
 either beaten with mallets or crushed between rollers in order to loosen them, and are 
 then steeped in water in large vats, between a perforated board at bottom and another 
 at top. The water being after some time drawn off the swoln and softened fruit, pres- 
 sure is applied to the upper board to extract all the soluble sweet matter, which passes 
 down through the false bottom, and flows off by an appropriate pipe into fermenting 
 tuns. The residuary fruit is infused with additional water, and then squeezed ; a pro- 
 cess which is repeated till all the sweets are drained off, after which the " rape" is sub- 
 jected to severe pressure in a screw or hydraulic press. The wine, in the process of 
 the vinous fermentation, is occasionally passed through a great body of the rape to im- 
 prove its flavour, and also to modify the fermentative action ; it is afterwards set to 
 ripen in casks, clarified by being repeatedly racked off, and fined with isinglass. 
 
 WOOD PAVING. Amongst the numerous illustrations of the durability and 
 resistance of wood paving, reference may be made to the specimens : — 
 
 Yrs. Mths. 
 
 At Whitehall, 1093 yards, laid in December 1839 - - - 3 4 
 
 In Fore Street, 521 yards, laid in October 1840 - - - - 2 6" 
 
 Under the Arch in Scotland Yard, 54 yards (8 feet wide), laid in Oct. 1841 1 6 
 
 The first, in every respect a perfect piece of pavement, has been for more than 3 years 
 subjected to a constant traffic, including the utmost amount of percussion from velocity, 
 and the extremest pressure from the ponderous engines which have been transported 
 over its surface. Scarce less may be said of that in Fore Street, whilst the specimen in 
 Scotland Yard has successfully withstood at least a like amount of pressure, the traffic 
 from the wharfs in Great Scotland Yard being no less than 78,000 tons per annum ; 
 the passage, narrowed within the limit of a single carriage line, exposing the wood to 
 the most critical test of resistance. 
 
 Slipperyness is not a natural defect in wood paving. The accumulations on wood 
 pavement are drawn from the proximate areas of granite and macadam. In granite the 
 imperfect structure admits of the constant oozing of dust and filth ; in macadam the sur- 
 face is always wearing into dirt and slop. In dry, hot, or cold weather the stone-paved 
 streets of London are proverbially as slippery as glass, whilst slipperyness on wood 
 pavement may be altogether obviated by cleanliness ; and that may now be ensured by 
 the use of Whitworth's cleansing machine, which has already been successfully tried in 
 some of the principal streets — thanks to the Commissioners of Woods and Forests. 
 
 It is impossible not to perceive the great amount of suffering and loss that may be 
 saved in horses by the wood pavement. Cabmen and omnibus drivers assure us that, 
 in the winter season, for a month or two only, there is any serious cause for complaint, 
 and then there is as much or more danger on other pavements ; whereas, during the 
 summer months, the advantages of wood over all other pavements is immense ; the 
 great mortality of horses in the streets of London, from over-driving during the hot 
 weather, is well known ; so far as wood is concerned, the reduction of effort must neces- 
 sarily decrease the destruction in a greater ratio than even 5 to 2. 
 
 Nn 
 
274 
 
 YEAST, ARTIFICIAL. 
 
 WOOD-PRESERVING. Mr. Bethell's invention consists in impregnating wood 
 throughout with oil of tar and other bituminous matters, containing creosote, and also 
 with pyrolignite of iron, which holds more creosote in solution than any other watery 
 menstruum. 
 
 The wood is put in a close iron tank, like a high-pressure steam-boiler, which is then 
 closed and filled with the tar oil or pyrolignite. The air is then exhausted by air-pumps, 
 and afterwards more oil or pyrolignite is forced in by hydrostatic pumps, until a pres- 
 sure equal to from 100 to 150 pounds to the inch is obtained. This pressure is kept 
 up by the frequent working of the pumps during six or seven hours, whereby the wood 
 becomes thoroughly saturated with the tar oil, or the pyrolignite of iron, and will be 
 found to weigh from 8 to 12 pounds per cube foot heavier than before. 
 
 In a large tank, like one of those used on the Bristol and Exeter Railway, 20 loads 
 of timber per day can be prepared. 
 
 The effect produced is that of perfectly coagulating the albumen in the sap, thus pre- 
 venting its putrefaction. For wood that will be much exposed to the weather, and 
 alternately wet and dry, the mere coagulation of the sap is not sufficient ; for although 
 the albumen contained in the sap of the wood is the most liable and the first to putrefy, 
 yet the ligneous fibre itself, after it has been deprived of all sap, will, when exposed in 
 a warm damp situation, rot and crumble into dust. To preserve wood, therefore, that 
 will be much exposed to the weather, it is not only necessary that the sap should be 
 coagulated, but that the fibres should be protected from moisture, which is effectually 
 done by this process. 
 
 The atmospheric action on wood thus prepared renders it tougher, and infinitely 
 stronger. A post made of beech, or even of Scotch fir, is rendered more durable, and 
 as strong as one made of the best oak ; the bituminous mixture with which all its pores 
 are filled acting as a cement to bind the fibres together in a close tough mass ; and the 
 more porous the wood is, the more durable and tough it becomes, as it imbibes a 
 greater quantity of the bituminous oil, which is proved by its increased weight. The 
 materials which are injected preserve iron and metals from corrosion ; and an iron bolt 
 driven into wood so saturated remains perfectly sound and free from rust. It also 
 resists the attack of insects ; and it has been proved by Mr. Prichard, at Shoreham 
 Harbour, that the teredo navalis, or naval worm, will not touch it. 
 
 Wood thus prepared for sleepers, piles, posts, fencing, &c, is not at all affected by 
 alternate exposure to wet and dry ; it requires no painting, and after it has been ex- 
 posed to the air for some days it loses every unpleasant smell. 
 
 This process has been adopted by the following eminent engineers — viz., Mr. Robert 
 Stephenson, Mr. Brunei, Mr. Bidder, Mr. Brathwaite, Mr. Buck, Mr. Harris, Mr. 
 Wickstead, Mr. Prichard, and others ; and has been used with the greatest success on 
 the Great Western Railway, the Bristol and Exeter Railway, the Manchester and 
 Birmingham Railway, the North Eastern, the South Eastern, the Stockton and Dar- 
 lington, and at Shoreham Harbour; and lately, in consequence of the excellent appear- 
 ance of the prepared sleepers, after three years' exposure to the weather, an order has 
 been issued by Mr. Robert Stephenson, that the sleepers hereafter to be used on the 
 London and Birmingham Railway are to be prepared with it before being put down. 
 
 The expense of preparing the wood varies from 10s. to 15s. per load, according to 
 situation, and the distance from the manufactories where the material is made. 
 
 Mr. Beth ell supplies the material at a low price from his manufactories, either at 
 Nine Elms, Vauxhall ; Bow Common; or Birmingham; and parties prepare the timber 
 themselves. 
 
 For railway sleepers it is highly useful, as the commonest Scotch fir sleeper, when 
 thus prepared, will last for centuries. Those which have been in use 3 years and up- 
 wards look much better now than when first laid down, having become harder, more 
 consolidated, and perfectly waterproof ; which qualities, combined with that of per- 
 fectly resisting the worm, render this process eminently useful for piles, and all other 
 woodwork placed under water. Posts for gates or fencing, if prepared in this manner, 
 may be made of Scotch fir, or the cheapest wood that can be obtained, and will not 
 decay like oak posts, which invariably become rotten near the earth after a few years. 
 
 Y. 
 
 YEAST, ARTIFICIAL. Mix two parts, by weight, of the fine flour of pale 
 barley malt with one part of wheat flour. Stir 50 pounds of this mixture gra- 
 dually into 100 quarts of cold water, with a wooden spatula, till it forms a smooth 
 pap. Put this pap into a copper over a slow fire ; stir it well till the temperature rise 
 to fully 155° to 160°, when a partial formation of sugar will take place, but this sweet- 
 ening must not be pushed too far ; turn out the thinned paste into a flat cooler, and 
 
ZINC. 
 
 275 
 
 stir it from time to time. As soon as the wort has fallen to 59° Fahr., transfer it to 
 a tub, and add for every 50 quarts of it 1 quart of good fresh beer-yeast, which will 
 throw the wort into brisk fermentation in the course of 12 hours. This preparation 
 will be good yeast, fit for bakers' and brewers' uses, and will continue fresh and active 
 for 3 days. It should be occasionally stirred. 
 
 When beer-barm has become old and flat, but not sour, it may be revived by mixing 
 with every quart of it a small potato, boiled, peeled, and rubbed down into a paste. 
 The mixture is to be placed in a warm situation, where it will speedily show its 
 renewed activity, by throwing up a froth upon its surface. It must be forthwith 
 incorporated with the dough, for the purpose of baking bread. When the barm has 
 become sour, its acid should be neutralised with a little powdered carbonate of soda, 
 and then treated as above, when it will, in like manner, be revived. A bottle of brisk 
 small beer may furnish ferment enough to form, in this way, a supply of good yeast 
 for a small baking. 
 
 The German yeast imported into this country in large quantities, and employed by 
 our bakers, in baking cakes, and other fancy bread, is made by putting the unterhefe 
 (see Beer, Bavarian), into thick sacks of linen or hempen yarn, letting the liquid part, 
 or beer, drain away ; placing the drained sacks between boards, and exposing them to 
 a gradually increasing pressure, till a mass of a thin cheesy consistence is obtained. 
 This cake is broken into small pieces, which are wrapped in separate linen cloths ; 
 these parcels are afterwards enclosed in waxed cloth, for exportation. The yeast 
 cake may also be rammed hard into a pitched cask, which is to be closed air-tight. 
 In this state, if kept cool, it may be preserved active for a considerable time. When 
 this is to be used for beer, the proportion required should be mixed with a quantity of 
 worts at 60° Fahr., and the mixture left for a little to work, and send up a lively 
 froth ; when it is quite ready for adding to the cooled worts in the fermenting back. 
 
 Yeast, Patent. Boil 6 ounces of hops in 3 gallons of water 3 hours; strain it off, 
 and let it stand 10 minutes ; then add half a peck of ground malt, stir it well up, and 
 cover it over ; return the hops, and put the same quantity of water to them again, 
 boiling them the same time as before, straining it off to the first mash ; stir it up, and 
 let it 'remain 4 hours, then strain it off, and set it to work at 90°, with 3 pints of patent 
 yeast ; let it stand about 20 hours ; take the scum off the top, and strain it through 
 a hair sieve ; it will be then fit for use. One pint is sufficient to make a bushel 
 of bread. 
 
 Z. 
 
 ZINC. Mr. Nicholas Troughton, of Swansea, obtained a patent in May 1839 
 for improvements in the manufacture of this metal. His invention relates to the appli- 
 cation of a peculiar apparatus in roasting the ores, and in smelting the zinc. Fig. 179. 
 
 represents the section of a series of retorts for calcining zinc ores, arranged and con- 
 structed according to this invention. The retorts shown in this figure are composed of 
 a series of fire-tiles or parallelogram slabs, a, a, a, are the slabs or tiles, which con- 
 stitute the bottoms of the retorts ; b, b, are the slabs, which constitute the upper sur- 
 faces or tops of the retorts ; and c, c, are slabs, placed vertically, to produce the sides of 
 the retorts. The back ends of the retorts are closed by similar tiles or slabs, having a 
 hole through them for the passage of the vapours evolved from the ores; these vapours 
 
 N n 2 
 
27b 
 
 ZINC. 
 
 are conveyed in any direction by the flue at that end, and being thus separated from the 
 products of combustion, may be separately acted on, according to either of the patentee's 
 former inventions, which treat of the separated vapours of copper ores in the process of 
 calcining or roasting such ores ; or the separated products of the ore may be allowed to 
 pass into the atmosphere. The patentee states, that by treating zinc ores in furnaces 
 or retorts, such as are above described, considerable saving of fuel will result, and the 
 zinc ore will be more evenly roasted or calcined. 
 
 The front ends of the retorts are closed by means of tiles or doors, having a small 
 hole or opening in each, for the passage of atmospheric air ; and the holes may be 
 closed, or more or less open, according to the object required. The retorts are charged 
 through the hoppers above, which have proper slides to close the openings into the 
 retorts; the quantity charged into each retort being sufficient to cover the lower surface 
 thereof two or three inches deep. During the operation the ore must be raked from 
 time to time, to change the surfaces, and the retorts should be kept to a moderate red 
 heat. 
 
 The second part of this invention relates to an arrangement of apparatus or furnace 
 for calcining zinc ores, wherein the ore is subjected to the direct action of the products 
 of combustion. Fig. 180. shows a longitudinal section of the furnace, which is so con- 
 
 structed that while one portion of the zinc ore is being heated in a manner similar to 
 the working of an ordinary calcining surface, other zinc ore is going through a pre- 
 paratory process by the heat that has passed away from the ore which is undergoing 
 the completing process of calcining. This furnace may be heated by a separate fire, to 
 burn by blast or by draft ; or the flue from the smelting furnace may be conducted into 
 the entrance of this furnace, and the otherwise waste heat of the smelting furnace will 
 be thus brought into useful application for calcining or roasting of zinc ore ; and 
 this part of the invention is applicable, whether it be applied to the furnace, or 
 to the retorts herein-before explained, and will be found a means of saving much 
 fuel in the processes of obtaining zinc from ore. a, fig. \ 80., represents the furnace, 
 which is suitable for blast, and a constant supply of fuel is kept up in the chamber b, 
 there being a close cover, with a sand-joint, c, is the bed or floor on which the ore is 
 spread, in like manner to an ordinary reverberatory furnace ; the ore is stirred about 
 on the floor by passing the ordinary rakes or instruments through the openings, d, d; 
 and when the process has been sufficiently carried on, the ore is discharged through the 
 openings e, e, which, at other times, remain closed by fire-tiles. The heat of the fire, 
 and the flame thereof, passing in contact with the ore on the floor or bed, c, also acts 
 on the roof,/, and that roof,/, being hot, reverberates the heat on to the floor or bed, 
 at the same time the heat, which passes through the roof, heats the ore in the upper 
 chamber, g ; and, in addition to such heat passing through the roof, the flame and 
 heat from the furnace, having passed over the zinc ore, in the lower compartment of the 
 apparatus, enters into and passes over the ore in the chamber g ; and, in doing so, heats 
 the roof h, of that chamber, and also the ore contained therein ; and it will be seen 
 that there is a third chamber, i ; the heat, therefore, which passes through the roof A, 
 heats the ore in the chamber i. In working this arrangement of calcining furnace or 
 apparatus, when the charge is withdrawn from the lower chamber, the charge in the 
 chamber g is to be raked into the lower chamber, through the openings for that pur- 
 pose, which, at other times, are kept covered with fire-tiles, as shown in the drawing ; 
 and the charge in the chamber i is to be raked into the chamber g, and a fresh supply 
 of ore charged into the chamber i. 
 
 The third part of this invention relates to a mode of arranging a series of retorts 
 side by side, and of applying heat thereto in the process of smelting or distilling zinc 
 from the ore. According to the practice most generally pursued in smelting zinc, the 
 ore is submitted to the action of heat in crucibles, having descending iron pipes, which 
 enter into vessels containing water : all which is well understood, as well as the process 
 of smelting or distilling zinc from the ores. Fig. 181. is a side elevation of two sets of 
 
ZINC. 
 
 277 
 
 furnaces and retorts, arranged according to this invention, 
 one of the furnaces heing in section; and Jig. 182. is a 
 transverse section of the same, a, a, are a series of retorts 
 of fire-clay, arranged, side by side, on a shelf of slabs or 
 fire-tiles. These retorts are each closed at one end and 182 
 open at the other, such open end being closed, when in 
 operation, by a tile or door, 6, fitting closely, and luted 
 with fire-clay, as will readily be traced in the drawing. 
 Each series of retorts is placed in a chamber, c, c, in such 
 
 a manner that the heat and flame of the fire will pass 
 
 from the fireplace or furnace, and act on one side 
 of the retorts ; and having passed along all the series, will proceed to the upper 
 part of the chamber, c,c, and heat the other side of the retorts; and as the fires are 
 maintained and urged by means of blasts of atmospheric air, the heat may be maintained 
 and regulated with great advantage, and at comparatively small cost. The blasts of air 
 may be produced by any ordinary blowing machinery, but rotatory blowers are pre- 
 ferred, and the air may be cold or heated. When anthracite coal is used as the fuel, 
 the patentee prefers adopting the hot blast, at a temperature of at least 500° Fahr., 
 and such heating may be performed by any of the well-known means now very 
 generally resorted to for heating the blasts of air for smelting iron, d, d, are iron 
 pipes, descending from the retorts and entering into vessels containing water, similar to 
 the apparatus at present in use for like purposes. Each chamber, c, is heated by its 
 separate furnace or fireplace, which have openings, to be closed when at work ; and in 
 order to keep up a supply of fuel to the fire, each fireplace has an inclined chamber, e, 
 which is filled with fuel, and then closed air-tight by the cover,/, fitting into a sand- 
 bath or joint, in order to prevent draught upwards. By this means the lower portion 
 only of the fuel will be in an ignited state when at work, g, g, are a series of iron doors, 
 one opposite the mouth of each retort ; these doors are capable of being removed by 
 sliding them upwards, till the portions cut out at the sides come opposite the dips or 
 holders, h, h, when the doors may be removed, in order to get at the retorts, i, is a 
 chamber in which the ore is heated previous to its being placed in the retorts. The 
 arrangement of the brickwork, the construction and setting of the furnaces, being 
 clearly shown in the drawing, no further description need be given. 
 
 The patentee remarks, that he is aware attempts have been made to employ retorts 
 in the smelting of zinc, and he does not, therefore, claim the same generally ; but he 
 does claim, in respect to the third part of this invention, the mode of placing a series of 
 retorts in a chamber, c, and causing the beat and flame to pass along, vmder and over, 
 such series of retorts, as above described ; and he also claims the mode of smelting zinc 
 by means of blast, whether the heat of the fuel is caused to act on a series of retorts or 
 vessels, in the manner shown, or on other arrangements of retorts or vessels, placed in 
 a suitable chamber or chambers. — Newton's Journal, xxm. p. 81. C. S. 
 
APPENDIX. 
 
 ALKALIMETRY. Twenty-eight years have elapsed since I was led, by peculiar 
 circumstances, to construct a very simple nlethod of testing alkalis, the principle of 
 which I soon afterwards applied to acids, bleaching powder, dye stuffs, and most other 
 chemical substances extensively used in manufactures. * In 1 8 1 4 and 1815, during the 
 summer vacation of my Glasgow classes, I was engaged in delivering courses of lectures 
 on chemistry in the Belfast Academical Institution, and had many of the most emi- 
 nent members of* the Linen Board of that town for my pupils. Being occasionally 
 consulted upon the qualities of the alkalis, which were used to the value of 200,000/. by 
 the linen bleachers of Ireland, I saw the importance to them of a simple alkalimetrical 
 test, both for purchasing and for using their barillas and potashes. The following 
 extract from the Belfast News Letter, of July 9th, 1816, will show the nature of my 
 contrivance : — 
 
 u This day one of the porters of the Linen Hall, Belfast, was called into the library 
 room at the request of Dr. Ure, who being quite unknown to Dr. Ure, and never 
 having seen any experiments made with acids and alkalis, he took the instrument at 
 our desire, which being filled with coloured acid, by pouring it slowly on adulterated 
 alkali, which we had previously prepared, he ascertained exactly the per centage of 
 genuine alkali in the mixture. Belfast, 25th June, 1816. 
 
 "(Signed) John S. Ferguson, Chairman. 
 
 James M'Donnel, M. D. 
 
 John M. Stoupe. 
 
 S. Thomson, M. D." 
 
 Of these gentlemen, two were leading members of the Linen Board, and the others 
 the two principal physicians of the town. The publication of the details of my method 
 of alkalimetry was delayed till arrangements were made for its general introduction, 
 under the direction of the Linen Board of Dublin, whose professor of chemistry, Mr. 
 W. Higgins, as well as Dr. Barker, professor of chemistry in Trinity College, granted 
 certificates of the " accuracy and the national importance" of the instrument. The 
 alkaline matter then imported into Ireland was often largely contaminated with common 
 salt, even to the extent of 80 or 90 per cent. During the procrastination of the Board, 
 I lent my Treatise on Alkalimetry to Dr. Henry, of Manchester, who inadvertently pub- 
 lished an account of it, though with reference to me, in the next edition of his Elements 
 of Chemistry. Having, in the long interval since, contrived many modifications of the 
 instrument, and having extended its principle to testing other articles, I am induced to 
 offer it now to the world, in consequence of the recent appearance of a publication upon 
 the same subject, by two very ingenious chemists of Liebig's school, Drs. K. Fresenius 
 and H. Will. Of their system of alkalimetry, &c. a copious abstract appeared in the 
 Annalen der Chemie und Pharmacie for July last, and about the same time a pamphlet 
 was published by Winter, at Heidelberg, under the title Neue Verfahrungsweisen zur 
 Bestimmung des Werthes der Pottasche und Soda, der Saiiren, und des Braunstein ; or 
 *« New Processes for determining the Value of Potash and Soda, of Acids, and Black 
 Oxide of Manganese." However accurate these processes may be, and however apt for 
 a German or French student of chemistry, they are, in my apprehension, not at all fitted 
 for the familiar use of manufacturers and dealers in any country, and certainly not for 
 those of the United Kingdom. 
 
 Descroizilles was the first person who contrived an instrument, called an Alkali- 
 meter, to ascertain the alkaline strength of potash and soda, without much calcula- 
 tion. His method was described in the Annales de Chimie for 1806, torn, lx., 
 and a translation of it appeared in our Philosophical Magazine, vol. xxviii., for July 
 
 * Among others to nitrate of potash, nitrate of soda, and to white lead, either in powder or in paint. 
 My nitrometer enables a person not at all versant in chemistry to ascertain in a quarter of an hour, 
 but by two distinct processes, the quantity of pure nitrate, in either of these salts, to one part in 200. 
 The cerussa-meter is equally simple and expeditious. 
 
280 
 
 ALKALIMETRY. 
 
 APPENDIX. 
 
 and August of the following year. His apparatus consisted of a glass tube, 8 or 9 
 inches long, and 7 or 8 lines in diameter, closed at one end, but terminated at the 
 other in a kind of small funnel (with a beak or spout), connected to the tube by a 
 narrow neck, having a calibre of two lines and a half. Upon the shoulder, under 
 the throat, there was a hole for admitting air to the long tube in the act of being 
 emptied, by sloping its mouth downwards. This cylindrical vessel was to contain 
 38 grammes of water, which space was divided into 76 equal parts, which it was 
 extremely important to proportion accurately. The liquor was prepared by taking 
 concentrated sulphuric acid, at 66° Baume (1-845 spec, grav.), and diluting it with 
 nine times its weight of water. The instrument being poised in a balance, he 
 introduced into it very exactly two grammes of the above test acid, and when the 
 instrument stood upright, he scratched a line at the level of the liquor, and thus 
 proceeded by addition of successive grammes to graduate the whole, till 36 were 
 added, after which he subdivided these spaces by lines into 72 demi-gramme volumes. 
 He then proceeds to describe eight different subsidiary articles required for his 
 operations : — 
 
 " Alkalimetrical trials of potash, — Weigh exactly one deci-gramme of potash, put it into 
 a glass, and pour upon it about four fifths of a decilitre of water ; facilitate the solution of 
 the potash by stirring it with a small chip of wood, three, or four times in an hour and a 
 half, a minute at each time. When the solution is effected, pour it into the small tin 
 measure, No. 4., which is to be then filled up with water; pour it back again into the 
 glass, in which you must still pour a measure full of pure water ; stir this new mixture 
 also three or four times within half an hour, in order to facilitate the precipitation of a 
 slight sediment, which soon falls down. This sediment being completely formed, 
 slope the glass with caution, in order to fill with clear liquor the small measure ; then 
 empty this last into another large glass ; after this place round the edges of a plate 
 drops of syrup of violets ; pour also into the alkalimeter test liquor until the line 
 marks 0 ; take it afterwards with the left hand, inclining it upon the glass which con- 
 tains the moiety of the clean alkaline solution : the acid liquor will fall into it by hasty 
 drops, or in a very small thread, which you may moderate at pleasure, by retarding the 
 entrance of the air at the lateral hole or vent, upon which must be placed the end of 
 the finger ; at the same time, with a small stick or match, assist the mixture and fa- 
 cilitate the development of the carbonic acid which is manifested by effervescence. 
 When you have emptied the alkalimeter to about the line 40, try if the saturation 
 approaches, by drawing your small stick from the mixture, and resting it upon the 
 drops of syrup of violets, which should become green, if the potash is not of a very 
 inferior quality. If, on the contrary, the violet colour is not altered, or what would 
 be worse, if it be changed into red, there would be, in the first case, an indication of 
 saturation, and in the second a proof of super-saturation. But this is not the case with 
 good potashes : at that line, the liquor tried can alter the syrup of violets into green 
 only ; or cause to return to the violet, and even to the green, the drops which had been 
 changed into red at the time of a former trial ; we must, therefore, in general add more 
 acid, which occasions a new effervescence. This addition must always be made with 
 caution, and we must touch every time a drop of syrup of violets in order to stop. 
 When at last the latter assumes a red hue, then, after having restored the alkalimeter 
 to a perpendicular position, in order to see at what line the testing liquor stops, you 
 must reckon one degree less, in order to compensate the excess of saturation. The mean 
 term of potashes is 56 ; this implies that they require for their saturation fifty-five hun- 
 dredths of their weight of sulphuric acid." 
 
 For the analysis of commercial sodas of all kinds, M. Descroizilles prescribes using 
 ten and a half deci-grammes of this alkali, instead of the ten deci-grammes for potashes, 
 and proceeds as above detailed. In his table of results annexed, we find American 
 potashes called 60° to 63°. 
 
 American pearl ashes - 50° to 55° 
 
 Dantzic potash - - 45 to 55 
 
 Alicant soda - - - 20 to 33 
 
 It is obvious, from these statements, that the alkalimeter so made and graduated 
 denoted comparative, but not absolute, quantities of alkalies present in the com- 
 mercial samples. The rest of his very long memoir is occupied with what he calls the 
 graduation of potashes and sodas, the economy of their graduation, the proportions of 
 carbonic ncid in them, the processes of caustification, the presence of potash in all 
 lime which is burnt by a wood fire, origin of neutral soda, and probable origin of 
 natrum ; without any more explicit instructions. The instrument, as left in this vague 
 state, never was employed, nor could it come into use, among English manufacturers 
 and dealers. 
 
APPENDIX. 
 
 ALKALIMETRY. 
 
 281 
 
 The next alkalimeter, of which an account has been published, was my own. In con- 
 structing this instrument, I availed myself of the lights recently shed on chemical pro- 
 portions by Dr. Dalton's atomic theory, and I thus made it to represent, not relative, but 
 absolute measures of the amount of real alkali existing in any commercial sample. 
 The test-liquor used at that time was sulphuric acid, which is most readily and accurately 
 diluted to the requisite degree by means of a glass bead, very carefully made, of the 
 specific gravity that the standard acid should have. In order to make the test-liquor, 
 therefore, nothing more is requisite than to put the bead into distilled water, and to 
 add to it somewhat dilute but pure sulphuric acid, slowly and with agitation, till the 
 bead rises from the bottom, and floats in the middle of the liquor at the temperature of 
 60° Fahr. The delicacy of this means of adjustment is so great, that a single degree of 
 increase of heat will cause the bead to sink to the bottom — a precision which no hydro- 
 meter can rival. The test-tube, about 14 inches long, contains generally 1000 grains 
 of water, and is graduated into 100 equal parts by means of equal measures of mercury. 
 The test-liquor is faintly tinged with red cabbage or litmus ; so that the change of 
 colour, as it approaches to the saturating pitch, on adding it to 100 grains of the com- 
 mercial alkali, becomes a sure guide in conducting the experiment to a successful issue. 
 One hundred measures of this test-liquor neutralise exactly 100 grains of absolute soda 
 (oxide of sodium), and of course very nearly 1 50 of potash. A bead may also be ad- 
 justed for test-liquors, of which 1000 grain measures neutralise 100 of potash, and 
 therefore 66§ of soda, as well as other proportions, for special purposes of greater 
 minuteness of research. One may be so graduated as to indicate clearly a difference of 
 T ^5 of a grain of ammonia. In making such nice experiments, it is of course requisite to 
 free the alkaline matter beforehand from sulphurets, sulphites, and hyposulphites, by 
 igniting it in contact with chlorate of potash, as long since recommended by Gay- 
 Lussac. With such means in careful hands, all the problems of alkalimetry may be ac- 
 curately solved by an ordinary operator. 
 
 On the same principle, my Acidimeter is constructed ; pure water of ammonia is 
 made of such a standard strength by an adjusted glass bead, as that 1000 grain mea- 
 sures of it neutralise exactly a quantity of any one real acid, denoted by its atomic 
 weight, upon either the hydrogen or oxygen scale or radix; as for example, 40 grains 
 of sulphuric acid. Hence it becomes a universal acidimeter ; after the neutralisation 
 of 10 or 100 grains of any acid, as denoted by the well defined colour in the litmus- 
 tinted ammonia, the test-tube measures of ammonia expended being multiplied by the 
 atomic weight of the acid, the product denotes the quantity of it present in 10 or 100 
 grains. The proportion of any one free acid in any substance may thus be deter- 
 mined with precision, or to one-fiftieth of a grain, in the course of five minutes. Like 
 methods are applied to Chlorometry, and other analytical purposes, with equal facility ; 
 adapting the test-liquor to the particular object in view. Instead of using beads for 
 preparing the alkalimetric and acidimetric test-liquors, specific gravity bottles, or hy- 
 drometers, may of course be employed ; but they furnish incomparably more tedious, 
 and less delicate means of adjustment. To adapt the above methods to the French 
 weights and measures, now used generally also by the German chemists, we need only 
 substitute 100 deci-grammes for 100 grains, and proceed in the graduation, &c. as already 
 described. 
 
 The possession of two reciprocal test-liquids affords ready and rigid means of verifi- 
 cation. For microscopic analyses of alkaline and acid matter, a graduated tube of 
 small bore, mounted in a frame with a valve apparatus at top, so as to let fall drops of 
 any size, and at any interval, is desirable ; and such I have employed for many years. 
 Of this kind is my ammonia-meter, used in the ultimate analysis of guanos and other 
 azotized products, in conjunction with a modified apparatus on the principle of that 
 of Varrentrapp and Will. It may be remarked, that when the crude alkali contains 
 some hyposulphite, it should not be calcined with chlorate of potash, because one atom 
 of hyposulphurous acid is thereby converted into two atoms of sulphuric, which 
 of course saturate double the quantity of alkali, previously in combination with the 
 hyposulphurous acid. In such cases it is preferable to change the condition of 
 the sulphurets, sulphites, and hyposidphites, by adding a little neutral chromate of 
 potash to the alkaline solution, whence result sulphate of chromium, water, and 
 sulphur, three bodies, which will not affect the accuracy of the above alkalimetrical 
 process. 
 
 In the Annals of Philosophy for October, 1817, I described a new instrument for 
 analysing the earthy and alkaline carbonates, and for determining the quantity of base 
 present in them from the volume of carbonic acid, disengaged by their solution in acids, 
 upon the data of the atomic theory. This method was applied to the analysis of the 
 carbonates of ammonia, soda, potash, lime, magnesian limestone (dolomite), &c. 
 
 " The indications of the above analytical instrument are so minute as to enable us, 
 by the help of the old and well-known theorem for computing the proportions of two 
 
 Oo 
 
282 
 
 ALKALIMETRY. 
 
 APPENDIX. 
 
 metals from the specific gravity of an alloy, to deduce the proportions of the bases 
 from the volume of gas disengaged by a given weight of a mixed carbonate."* 
 
 That small instrument consisted of a bent glass tube, open at one end, and terminated 
 at the other with an egg-shaped bulb from two to three inches in diameter, and it 
 required for operating with it, about five pounds of quicksilver. The following glass 
 apparatus {fig. 183.) will be found more generally convenient, and equally exact, a is 
 a cylinder 2 inches in diameter, and 14 inches long. It con- 
 tains 10,000 grains of water in the graduated portion ; o, or zero 
 being at the top. It has a tubulure in the side close to the 
 bottom, through the cork of which a short tube passes tight, and 
 is connected to a collar of caouchouc, e, which serves for a joint 
 to the upright tube, b, resting near its open upper end in a 
 hooked wire. Through the cork in the mouth of the cylinder, 
 the taper tail of the flask c passes air-tight. The small tube f, 
 open at both ends, is cemented at bottom into the tail of c, 
 and rises to the shoulder of the flask. The cork of c is per- 
 forated, and receives air-tight the taper tube d, which can also 
 be closed with the stopcock. 
 
 In operating with this apparatus, proceed as follows : — 
 Fill the cylinder with water, and cover its surface with half 
 an inch of oil. Insert the tail of the flask. Put into the flask 
 c, 58 -6 grains of carbonate of potash, or 45*2 of carbonate of soda, 
 according as common pearl-ash or soda-ash is to be tested, along 
 with as mvich water as will cover fully the lower end of n, and 
 then introduce this tube. Have a bottle containing about 40 
 parts of oil of vitriol, previously mixed with 60 of water, and 
 cooled. Take of this, in a pouring or dropping glass, 100 water 
 grain measures, and suck this quantity gradually up into the tube 
 n, then shut the stopcock. On opening it slightly the acid will 
 fall into c, and as slowly as may be prudent. The carbonic acid 
 gas, forthwith disengaged, will depress the water in a, cause an 
 overflow of it from the tube b, which, being held in the left hand, 
 must have its swanbeak placed over a basin, and progressively 
 lowered to the level of the descending water in the cylinder. 
 When all the sulphuric acid has been introduced by the right hand, 
 the orifice of n is to be corked, and the tube b continually lowered 
 with the left, till the effervescence being finished, the water in a 
 remains stationary. The number on the centigrade scale, opposite 
 to the surface of the oil, deducting 100 grain measures for the 
 bulk of dilute acid added, denotes the per centage of pure carbonate of potash, or of 
 soda, in the sample under examination. The above prescribed weights of these two 
 carbonates, when pure, disengage each by the action of sulphuric acid (used here in 
 small excess) 10,000 water grain measures of carbonic acid gas, or 100 measures 
 of the scale on a. The cylinder which I employ contains about 12,000 water grain 
 measures, so that the bottom of the centigrade scale is fully two inches above the level 
 of the lower tubulure. This capacity and the graduation into 120 parts, will be found 
 convenient in certain cases, particularly in analysing bicarbonates of potash and soda, f 
 We may estimate 10,000 water grain measures of carbonic acid at 60° Fahr. to 
 weigh 18*4 grains, and we thus perceive what a magnified scale we should possess, if 
 we applied the vernier contrivance here, as we do to barometers. At any rate, he must 
 be an awkward operator who cannot determine the value of an alkaline carbonate, by 
 the above means, to one part in a thousand. 
 
 In operating upon limestones, marles, &c., 42*1 grains should be taken as the 
 standard weight of assay, because that weight of pure carbonate of lime should give 
 out on solution in dilute muriatic acid 10,000 water grain measures of carbonic acid 
 gas. Since 100 water grain measures of liquid hydrochloric acid, specific gravity 1 '14, 
 will supersaturature the lime in the above weight of carbonates, that quantity may be 
 used in the experiment. The preceding instrument will be found more convenient in 
 experimenting, as also the system of indication, than one on similar principles con- 
 structed by the ingenious Dr. Mohr, of Coblenz. 
 
 In examining bicarbonates of potash and of soda, the weights to be used in the above 
 apparatus are 42 grains of the former, and 35] grains of the latter, each of which 
 
 * Dictionary of Chemistry, 1821. 
 
 t For the greatest precision hot acid may be used in the above experiment, by taking in a graduated 
 test-tube seventy-five grains of water, and filling it up to the line 100 with concentrated sulphuric acid. 
 This mixture being poured in successive portions into the flask c (represented much too large in pro- 
 portion to the cylinder a), will ensure the expulsion of all the carbonic acid from c, which may be after 
 wards cooled by wrapping round it a towel dipped in cold water. 
 
APPENDIX. 
 
 ALKALIMETRY. 
 
 283 
 
 quantities, if the salts be perfect, will disengage 10,000 water grain measures of car- 
 bonic acid gas, by the action of sulphuric acid. There will he no harm in taking the 
 formerly prescribed measure of the sulphuric acid, though considerably less would 
 answer the purpose. The centigrade measures of gas obtained in a will indicate the 
 carbonated state of the two alkalies respectively. Their alkaline force may be most 
 readily ascertained by my old alkalimeter, with coloured test acid. Since the bicar- 
 bonates usually sold in our shops, especially that of soda, are far from being exact 
 atomic compounds, they should be always examined, both for their base and acid, 
 which may also be well done in the following way, where the quantity of carbonic acid 
 gas is determined by weight instead of by volume. 
 
 For this purpose, a small compact apparatus of the annexed form (fig. 184.) will be 
 found convenient ; it is to be used in conjunction with my 
 alkalimeter. a in the dotted line is the phial for receiving 
 the carbonate to be tested, b, the funnel into which the 
 test acid is to be poured ; c c, an inverted syphon filled 
 with pieces of chloride of calcium for absorbing the aqueous 
 vapours exhaled by the carbonic acid. The loss of weight 
 in the phial above that in the tube of test acid shows the 
 quantity of acid gas, and the indication of the alkalimeter 
 tube, that of alkaline base, from which data the proportion 
 of neutral carbonate and bicarbonate may be immediately 
 deduced. Thus, 100 grains of bicarbonate of soda should 
 give out 51? grains of carbonic acid, and saturate 37*6 cen- 
 tigrade measures of the test acid, equivalent to 37*6 grains 
 of real soda. But if neutral carbonate of soda be present, 
 less gas v/ill be given out, and more or less alkali may be 
 indicated, according to the degree of dryness of the neutral 
 soda. The amount of water in the bicarbonate may be de- 
 termined by igniting 20 grains in a test tube, connected with 
 the chlorcalcium inverted syphon; 10^ grains of carbonic 
 acid gas should be expelled, and 2^ of water, making a total 
 loss of 12^ grains, of which 2± will be found as water absorbed 
 by the chlorcalcium. But since a very moderate heat suffices 
 to expel the second atom of carbonic acid from the bicar- 
 bonate of soda, the readiest mode of estimating its quality is 
 to heat, over a spirit lamp, in a small flask, or retort, con- 
 nected air-tight by a tube with the mouth of the cylinder 
 A, {fig. 183.), 70| grains of the supposed bicarbonate. Of 
 the perfect salt this quantity should give out pretty ex- 
 actly 10,000 grain measures of gas; and whatever aliquot part of this volume is 
 evolved will indicate, without calculation, the relative value of the substance as a 
 bisalt. Thus if 8500 grain measures of gas are obtained, 85 parts of bicarbonate 
 of soda are present in 100. The crystalline form of bicarbonate of potash is a tolerably 
 good criterion of its quality. 
 
 The quantity of caustic alkali mixed with carbonate may be readily determined, 
 with sufficient accuracy, by the expert use of my alkalimeter ; because, till the caustic 
 portion be nearly neutralised, little or no carbonic gas is expelled. When the 
 effervescence at length begins, the test measures already expended denote the per- 
 centage of caustic alkali. It is not right to disregard the alkali which is present in the 
 state of sulphuret, because as such it is effective in many processes of the chemical arts ; 
 in the manufacture of yellow soap, crown glass, in the bleaching of linen and 
 cotton goods, &c. The alkalimeter, directly applied, will show the alkali present 
 in this form, when compared with that indicated after ignition of the crude alkali 
 with chlorate of potash, or after its treatment with yellow chromate of potash.* 
 
 A few years ago I had the following apparatus made for the ready analysis of car- 
 bonates, by ascertaining the loss of weight they suffered from the disengagement of their 
 carbonic acid gas, during their solution in an acid, a, b, (fig. 185. ) are two globes, of about 
 two inches in diameter each ; a has its inferior neck strangled into a bore nearly capil- 
 lary; b stands lower, with its centre line on a level with the narrow neck of b. The 
 tubes of these globes are about one-half inch in diameter, c is shut at top with a per- 
 forated cork, through which enters, air-tight, a small glass tube, which is bent across to 
 the mouth of the tube e, and then passes down into it a little below the centre line of 
 
 * If the alkaline carbonate contains sulphuret, sulphite, or hyposulphite, a teaspoonful of yellow 
 chromate of potash may be added to it, wherefrom result sulphate of chromium water and sulphur 
 which remain in the apparatus without affecting its weight. '1 he mutual action of neutral chromate ot 
 potash, and of sulphuret of potash, &c, has been discussed in an ingenious paper published by Dipping, 
 in the Annalcn der Chemie for May, 1843, p. 172. 
 
 Oo 2 
 
284 
 
 ALKALIMETRY. 
 
 APPENDIX. 
 
 185 
 
 the globe b. This globe is rather more than half filled with sulphuric acid, when the 
 instrument is employed in the analysis of the carbonates. The standard weight of car- 
 bonate of soda = 24| grains, or of carbonate of potash = 
 3 1 i grains, is then put into a, having previously laid a 
 minute globe of. glass over the lower orifice ; the cork, 
 with its small tube, is now firmly, adjusted ; and the appa- 
 ratus is weighed in its upright position, either by suspension 
 with a hook to the end of the beam, or by resting it on the 
 scale in a light socket of any kind. It is next laid hold of, 
 and inclined so as to cause a little of the acid in b to pass 
 over into a. Effervescence ensues with greater or less 
 vehemence, according to the nature of the carbonate and 
 quantity of the acid introduced. Should it be too violent, 
 and threaten an overflow by intumescence, it can be in- 
 stantly abated to any degree by the slightest slope of the 
 instrument. Now, this power of control forms the pe- 
 culiar feature and advantage of this contrivance ; whereas 
 in all other forms of such apparatus that I know, whether 
 by sucking over or pouring in, if a little too much acid 
 comes upon the carbonate, the experiment is effectually 
 marred. The gas disengaged in a must necessarily tra- 
 verse the sulphuric acid in b, and be stripped of its 
 moisture before escaping into the air. Having super- 
 saturated the alkaline base, and cooled the apparatus, 
 we weigh it again, and the loss of weight in grains and 
 tenths denotes the per centage of soda or potash, provided 
 their neutral carbonates had been the subjects of experi- 
 ment. For limestone, on the same plan of computation, 
 22;{ grains may be taken. It deserves to be noted, that the 
 present instrument has only orie junction, and needs no 
 chloride of calcium, a substance so apt by its swelling to burst the glass tubes that 
 contain it.* 
 
 II. ACIDIMETBY. 
 
 I have already stated, that water of ammonia of standard strength, faintly tinted 
 with litmus, affords a most exact and convenient acidimeter, when poured or let fall 
 from a graduated dropping-tube. Bicarbonate of potash also, when dissolved in water, 
 so that 1000 grain measures contain one atom of the salt counted in grains, is a good 
 test-liquor for the same purpose ; for if the centigrade-measures expended in effecting 
 neutralisation are multiplied by the atomic weight of the given acid, the product is 
 the quantity in grains of acid present. 
 
 Acidimetry may be likewise exactly performed by measuring in the cylindric gas- 
 meter {Jig. 183.) the volumes of carbonic acid gas disengaged from pure bicarbonate of 
 potash or soda, by a given weight of any acid, taking care to use a small excess of the 
 salt. Thus, for example, 16"8 grains of dry and 20| of hydrated sulphuric acid disen- 
 gage 10,000 water grain measures of gas from bicarbonate of potash. Therefore, if 
 20if grains of a given sulphuric acid be poured into the flask of Jig. 183., upon about 50 
 grains of the bicarbonate, powdered and covered with a little water, it will cause the 
 evolution of a volume of gas proportioned to its strength. If the acid be pure oil of 
 vitriol, that weight of it will disengage 10,000 grain measures of gas ; but if it be 
 weaker, so much less gas — the centigrade-measures of which will denote the per cen- 
 tage value of the acid. If the question be put, how much dry acid is present per cent, 
 in a given sulphuric acid, then 16-8 grains of the acid under trial must be used ; and 
 the resulting volume of carbonic acid gas read on the scale will denote the per 
 centage of dry acid.f 
 
 For nitric acid, we should take 22*6 grains ; for hydrochloric or muriatic acid, 15*34 ; 
 for acetic acid, 21 for citric acid, 24*6; for tartaric acid, 28 grains : then in each 
 case we shall obtain a volume of carbonic acid gas proportioned to the strength and 
 purity of these acids respectively. The nitric, hydrochloric, and acetic acids are re- 
 ferred to in their anhydrous state ; the tartaric and citric in their crystalline. If the 
 latter two acids be pure, a solution of 24*6 grains of the first and of 28 of the last 
 
 * 1000 water-grain measures of sulphuric acid of specific gravity P032, or 32 above water, neutralize 
 32 grains of soda, and, consequently, one atom, on the hydrogen scale, of each of the other bases, rec- 
 koned in grains. 
 
 Having in the course of many years subjected my tables of sulphuric, nitric, and muriatic acids, as well 
 as of ammonia, to strict cross-examination, I have found them trustworthy for all alkalimetrical and 
 acuhmetrical purposes. 
 
 t The bicarbonate must be free from carbonate, a point easilv secured bv washing its powder with 
 cold water, and drying it in the air. 
 
APPENDIX. 
 
 ALKALIMETRY. 
 
 285 
 
 186 
 
 will disengage from 50 grains of bicarbonate of potash 10,000 grain measures of car- 
 bonic acid gas. * 
 
 Acidimetrical operations may likewise be performed by determining the weight 
 of carbonic acid gas expelled from the bicarbonate of potash or soda, by a given quan- 
 tity of any acid, in the apparatus either^. 184. or fig. 185. Here the weights to be 
 taken are as follows, in reference to 
 
 Grains. 
 
 Dry Sulphuric acid - 9-127 
 „ Nitric - - - - 12-33 
 „ Hydrochloric - - 8-29 
 „ Acetic - - - - 11-67 
 Crystallized Tartaric - - 13-31 
 Citric - - 15-13 
 
 Each of these quantities of real acid, with 25 or 26 grains of bicarbonate of potash, 
 will give off 10 grains of carbonic acid gas; and hence whatever weight the apparatus 
 loses, being reckoned in grains and tenths of a grain, denotes the 
 per centage of acid in the sample under trial, without the ne- 
 cessity of any arithmetical reduction. Persons accustomed to 
 the French metrical system may use deci-grammes instead of 
 grains, and they will arrive at the same per centage results. 
 
 The preceding experiments, in reference to the weight of car- 
 bonic acid gas expelled for the purpose of either alkalimetry or 
 acidimetry, may also be made by means of the ordinary apparatus 
 represented in fig. 186. a is a small matrass which contains the 
 acid or carbonated alkali at its bottom ; and conversely the alkali 
 or acid, for their mutual decomposition in the small test-tube, 
 shown first at b nearly upright and filled, but afterwards at a, 
 horizontal and emptied, b is a bulhous tube filled with frag- 
 ments of chlorcalcium for absorbing the aqueous vapour that 
 rises with the carbonic acid gas, and d c is a small bent tube 
 which dips into the liquid in the matrass. The weighings, &c, 
 may be conducted as already detailed ; and when the effer- 
 vescence is completed, the residuary gas is sucked up through 
 b, while the atmospheric air enters to replace it at the orifice d 
 of the bent tube. 
 
 The new methods which pervade the whole treatise of Drs. 
 Fresenius and Will are all based on the principle of estimating 
 alkalinity, acidity, and the oxygen in manganese (or chloro- 
 metry) by the weight of carbonic acid gas evolved. As in 
 taking these measures the gas must be discharged without 
 carrying water off with it, an elegant and ingenious little piece 
 of apparatus has been invented by the authors for effecting that 
 purpose, and it will do it well, a and b {fig. 187.) are two flasks (wide-mouthed 
 medicine bottles may be employed), a must have a capacity of from 2 ounces to 21 
 
 ounces of water ; it is advisable that b should be 
 somewhat smaller, say of a capacity of about 1 to 
 11 ounces. Both flasks are closed by means of 
 doubly perforated corks. These perforations serve 
 for the reception of the tubes a, c, and d. c is a 
 tube bent twice at right angles, which enters at 
 its one end just into the flask a, but descends at 
 its other end, near to the bottom of b. These tubes 
 are open at both ends when operating ; except the 
 top end b of the tube a, which is closed by means 
 of a pellet of wax. The substance to be ex- 
 amined is weighed and put into the flask a, into 
 which water is then poured to the extent of ope 
 third of its capacity. b is filled with common 
 English sulphuric acid to about half its capacity. 
 Both flasks are then corked (by which they be- 
 come united by the rectangular tube), and the 
 apparatus is weighed. 
 
 The air of the whole apparatus is next rarefied by 
 applying suction to the tube d : the consequence is, 
 • that the sulphuric acid contained in b ascends into 
 
 * The expulsion of the gas may be completed by surrounding the flask with a towel dipped in hot 
 Water. 
 
286 
 
 ALKALIMETRY. 
 
 APPENDIX. 
 
 the tube c, and thus a portion of it flows over into b. Immediately upon its coming 
 into contact with the carbonate contained in a, carbonic acid gas is disengaged, and in 
 its escape must necessarily traverse the oil of vitriol in b, and therein deposit all its 
 aqueous vapour before issuing from d. The sulphuric acid in passing over into a heats 
 the mixture at the same time, and thus promotes the expulsion of the gas. Whenever 
 this ceases to flow, a little more sulphuric acid must be sent over into a by suction from 
 d (or rather from a recurved tube attached, pro tempore, to it) ; an artiiice which may 
 be repeated till no more gas can be expelled, even when the contents of a are heated, 
 as they must be at the end by the excess of oil of vitriol. 
 
 " From the aperture b of the tube a, which has been all the time closed, the bit of 
 wax is now to be removed, and to the tube connected with d, suction is to be applied, 
 till all the carbonic acid lodged in the apparatus be replaced by atmospheric air. The 
 whole is to be then cooled, wiped, and weighed ; the loss of weight indicates exactly 
 the quantity of carbonic acid which existed in the carbonate submitted to experiment. 
 The process is no less neat than it is simple, and does honour to the ingenuity of its 
 inventors. Their mode of deducing the per centage of alkali from the quantity of 
 carbonic acid discharged in the operation is also quite exact, and suitable for con- 
 tinental chemists familiar with gramme weights and calculations, but certainly not for 
 persons conversant only with ounces, drams, and scruples, or even with grain subdi- 
 visions. The whole book, however excellent, needs, for the British public, transpo- 
 sition, before it can serve in this country the purpose intended by its scientific authors. 
 Thus, in section 4., where several results of their analyses are given, the statements 
 have a somewhat mysterious aspect. Should any one ask why the oracular number of 
 4*83 grammes of carbonate of soda is used as their standard weight for analysis, he 
 can obtain no response in the book, either in a note or anywhere else. A German or 
 French student, familiar with chemical computation, will probably be able to discover 
 that 4*83 grammes of pure carbonate of soda contain, by Berzelius's tables of atomic 
 weights, 2 grammes of carbonic acid; for 53*47 (1 atom of carbonate) : 22*15 (1 of 
 carbonic acid) : : 4*83 : 2*00. Such is the simple solution of this apparent enigma, 
 and of some other similar puzzles in the book. Indeed, unless the reader is aware of 
 that proportion, he cannot see the grounds of the accordance in the results between 
 experiment and theory, or why the numbers 2*010, 1*993, and 2*020 are presented as 
 specimens of great precision. This accordance gives satisfaction when it is known 
 that these numbers, in experiments 1, 2, and 3, oscillate on one side or other so near to 
 the theoretical number 2*00. But 4 grammes and 83 centi-grammes, as also I gramme 
 and 995 milli-grammes, are awkward weights for an ordinary English chemist or 
 apothecary, which would require a month or two's residence in the laboratories of 
 Giessen and Paris to manipulate with readiness. 
 
 Again, in testing carbonate of potash, our authors take 6*29 grammes as their unity of 
 weight, undoubtedly, because, if pure, it should discharge, by saturation with the sul- 
 phuric acid, 2 grammes of carbonic acid. Here, however, they have not stuck so rigidly 
 as the school of Giessen usually does to Berzelius's atomic numbers ; for his atom ot 
 carbonate of potash is 69*42; whence, 22*15 : 69*42 : : 2*00 : 6*68, hydrogen = 1 *00 ; 
 or 276*44 : 866*33 : : 2*00 : 6*268 oxygen = 100. 
 
 Admitting the value of the new method in testing neutral carbonates, it cannot be 
 directly applied to the mixed carbonate and bicarbonate of soda, so commonly sold 
 in this country for bicarbonate; nor is it applicable to the case of a mixture of caustic 
 and carbonated alkali, without the tedious process of previous treatment with carbo- 
 nate of ammonia and heat. 
 
 The new German method of acidimetry consists in determining how much carbonic 
 acid gas is disengaged from a standard bicarbonate of soda, by a given weight of any 
 acid. The twin-flask apparatus {fig- 187.) is used. The weighed portion of acid is 
 put into a, and a sufficient quantity of the soda into a test tube, which is suspended 
 upright with a silk thread fastened by the pressure of the cork to the mouth of the 
 flask. On letting the thread loose, the test tube falls, and the cork being instantly re- 
 placed, the whole gas evolved is forced to pass through the sulphuric acid in b, and 
 there to deposit its moisture. The experiment is conducted in other respects as already 
 described for alkalimetry. 
 
 The following extract from Drs. Fresenius and Will's New Methods of Alkalimetry, 
 &c. will show the Giessen plan of calculating results : — 
 
 " The amount of anhydrous acid contained in the hydrated acid under examination 
 is determined from the amount of carbonic acid escaped, as follows : 
 
 " Two measures of carbonic acid bear the same proportion to one measure of the 
 anhydrous acid in question, as the amount of carbonic acid expelled does to the amount 
 sought of anhydrous acid. Thus, let us suppose, for instance, we had examined 
 dilute sulphuric acid, and obtained 1*5 grammes of carbonic acid, the arrangement 
 would be : 
 
APPENDIX. 
 
 ALKALIMETRY. 
 
 287 
 
 550 (2 x 275) : 501 = 1 -5 : x 
 x = 1-36. 
 
 The amount of sulphuric acid operated upon consequently would contain 1 -36 
 grammes of anhydrous acid. Let us suppose the weight of this amount to have 
 been 15 grammes, the sulphuric acid under examination would contain a per centage 
 amount of 9*06 ; for 
 
 15 : T'36 = 100 : x 
 x =-- 9-06."* 
 
 " Section XXIX. Stating the Quantities of the various Acids to be used in their 
 Examination. — To enable our readers at once, without the trouble of calculation, to 
 determine from the weight of carbonic acid expelled, the exact amount of anhydrous 
 acid contained in those acids which are of most frequent occurrence, we have subjoined 
 lists of certain quantities to be taken of each acid for experiment, so that the number 
 of centi-grammes of carbonic acid expelled will directly indicate the per centage 
 amount of anhydrous acid in the acid under examination. 
 
 " Multiples of those weights may of course be substituted for the numbers given, 
 according to the degree of dilution of the acid under examination. In such cases the 
 number of centi-grammes of the carbonic acid expelled must be divided by the same 
 number, which has served as the multiplier. 
 
 " These numbers are obtained by dividing the atomic weight of the acid by 550 
 (2 x 275, one eq. of carbonf), as follows: — 
 
 " Two eq. of carbonic acid, corresponding to one eq. of the acid to be exa- 
 mined, how much should be taken of the latter to expel 1 -00 grammes of car- 
 bonic acid? 
 
 " The arrangement for sulphuric acid, for instance, is as follows : 
 
 550 : 501 = 1 -00 : x 
 
 x = 0-91 (or, more correctly, 0*9 11). 
 
 " When examining acids, it is most advisable to use that multiple of the unity (ac- 
 cording to the degree of concentration) which will expel from one to two grammes of 
 carbonic acid. 
 
 "i. SULPHURIC ACID. 
 
 Unity 0*91 grammes (or, more correctly, 0-911 grammes) 
 " Multiples : 
 
 2 
 
 X 
 
 0-911 
 
 
 1-822 
 
 grammes 
 
 3 
 
 X 
 
 0-911 
 
 
 2-733 
 
 « 
 
 4 
 
 X 
 
 0-911 
 
 
 3-644 
 
 
 5 
 
 X 
 
 0-911 
 
 
 4-555 
 
 K 
 
 6 
 
 X 
 
 0-911 
 
 
 5-466 
 
 u 
 
 7 
 
 X 
 
 0-911 
 
 
 6-377 
 
 « 
 
 8 
 
 X 
 
 0911 
 
 
 7'288 
 
 « 
 
 9 
 
 X 
 
 0-911 
 
 
 8-199 
 
 
 10 
 
 X 
 
 0-911 
 
 
 9-110 
 
 
 15 
 
 X 
 
 0-911 
 
 
 13-665 
 
 (( 
 
 20 
 
 X 
 
 0-911 
 
 
 18-220 
 
 tt 
 
 30 
 
 X 
 
 0-911 
 
 
 27-330 
 
 « &C. 
 
 " Thus, knowing that 0*91 of anhydrous sulphuric acid will expel 1*00 of carbonic 
 acid, it will be easy to determine what multiple ought to be used, according to the de- 
 gree of concentration of the acid to be examined." i 
 
 III. CHEOROMETRY, 
 
 And the Testing of Black Oxide of Manganese for its available Oxygen. 
 
 The value of manganese may be estimated very exactly by measuring the quantity 
 of chlorine which a given weight of it produces with hydrochloric acid ; the chlorine 
 being at the same time estimated by the quantity of solution of green sulphate of iron, 
 which it will peroxidize. A process of this kind was long ago practised with chloride 
 of lime (bleaching powder or liquor) by Dr. Dalton ; and it has been since im- 
 proved by Mr. Waltercrum. As the conversion of two atoms of green sulphate of iron 
 into red sulphate requires only one atom of oxygen, this change may be effected by the 
 re-action of one atom of chlorine in liberating one atom of oxygen, while this appro- 
 priates one of hydrogen from the hydrochloric acid. 
 
 * New Methods of Alkalimetry, 8fC pp 93, 94. 
 
 t A typographical error in Mr. Bullock's edition ; it should be carbonic acid 
 \ New Methods oj Alkalimetry, %c. pp. 103—105. 
 
288 
 
 ALKALIMETRY. 
 
 APFENDIX. 
 
 The weight of 2 atoms of green sulphate of iron is 278 = (139 x 2), consisting of 2 
 atoms of protoxide = 72, + 2 of sulphuric acid = 80, + 14 of water = 126 ; in all = 278 ; 
 and this weight is equivalent to 36 of chlorine, to 8 of oxygen, and to 44 of peroxide of 
 manganese.* Therefore, if we take a solution of copperas, containing 278 grains in 
 1000 water grain measures, that volume of liquid will represent, by the conversion of 
 its protoxide into peroxide, exactly one atom, either of peroxide of manganese == 44 
 grains, or 1 atom of chlorine = 36. Hence the following plan of research : — 
 
 Into the flask or phial c of my chlorometric apparatus (Jig. 188.), put 100 grains of the 
 manganese to be tested, and into the globes a, b pour out 
 of an alkalimetrical tube charged with 1000 grain measures 
 of the above equivalent copperas solution, from 200 to 500 
 grain measures, according to the supposed quality of the 
 manganese ; then introduce through the funnel d some hydro- 
 chloric acid of known specific gravity (suppose 1*1), contain- 
 ing nearly 20 per cent, of chlorine, also from a charged 
 alkalimetrical tube, and apply gentle heat to the bottom of 
 the flask by placing it in a capsule of water standing over 
 a spirit lamp. The chlorine evolved will rise up through 
 the tube f, which passes merely beyond the cork, and will 
 enter into the solution in b and a, converting it into red 
 sulphate. Have ready some dry paper imbued with solution 
 of red ferrocyanide of potassium (red prussiate of iron). 
 Dip a slip of whalebone into the liquor in the globe a, 
 through the funnel e (represented in the figure rather too 
 high above the globe), and touch the paper with its point. 
 As long as it forms a blue spot, some of the iron still exists 
 as black oxide, and the process is to be urged by the ad- 
 dition of a little more hydrochloric acid to the manganese, 
 as long as chlorine gas continues to be disengaged, and while 
 it maintains the level of the liquor in a above that in b. 
 Whenever the liquor, by the re-action of the chlorine, ceases 
 to stain the test-paper blue, more of the solution from the 
 graduated tube must be added till it begins to do so. By 
 the cautious administration of the hydrochloric acid on the 
 one hand, and of the copperas liquor on the other, the term 
 of saturation will be arrived at in a few minutes. The 
 manganese has then produced all the chlorine which it can 
 yield. The number of water grain measures, of the liquor, 
 or degrees of its alkalimeter scale being multiplied by 44, 
 will give a product denoting the percentage of pure man- 
 ganese present in the sample ; or being multiplied by 36, a product which will denote 
 the quantity of chlorine by weight which 100 grains of it can serve to generate. 
 
 Since one atom of pure manganese (44 grains), in producing 36 grains of chlorine, 
 consumes 2 atoms = 74 grains of hydrochloric acid, the quantity of this acid expended 
 from the graduated tubes, beyond the due proportion of chlorine obtained, will show how 
 much of the acid is unprofitably consumed by foreign substances in the manganese. 
 In fact, every grain of chlorine should, with pyrolusite, be generated by an expenditure 
 of little more than 2 grains of real muriatic acid, or 10 grains weight of the dilute acid, = 
 about 9 grain measures of the graduated tube. Liquid hydrochloric acid of spec. grav. 
 1 '093 contains in 1000 grain measures exactly 200 grains of real acid. Hence 100 grains 
 of pure pyrosulite should produce about 82 grains of chlorine, and consume about 169 
 of real muriatic acid = 845 grain measures of liquid acid, spec. grav. 1 '093. Instead 
 of taking 100 grains of manganese as the testing dose, 10 or 20 grains may be taken, 
 according to the dimensions of the apparatus and the exactness of the operator. 
 
 But if it be wished to obtain direct per centages of manganese by the graduated tubes 
 without the trouble of reduction, then for a dose of 10 grains take a solution of fresh green 
 copperas (free from adhering moisture), containing 632 grains in 10,000 grain measures. 
 Proceed as above directed. If the manganese be a pure peroxide, 10 grains of it 
 
 * Berzelius, in the 4th edition of his Lehrbuch, rates the atom of the green sulphate of iron (ferrous 
 sulphate) at 129-43, hydrogen = 1, and considers it, after Mitscherlich, to contain only 6 atoms of water. 
 I have ascertained, hy the most careful experiments, that it contains 7 atoms of water ; and that 139 
 grains of it, or 138*44 (Berzelius) are equivalent to 1 atom of chlorbarium, and to very nearly 40 grains 
 of peroxide of iron. 
 
 This remarkable error has probably arisen from an attempt to measure the proportion of water in the 
 u c° m itS loss of wei " nt D >' desiccation. But I have found it impossible by this means to expel more 
 than 6 atoms of water without causing partial decomposition of the salt by disengagement of sulphuric 
 acid. The copperas so dried acquires such an affinity for water, that it absorbs fully one tenth of its 
 weight of moisture from the atmosphere in the course of an hour. 
 
APPENDIX. 
 
 ALKALIMETRY. 
 
 289 
 
 will generate as much chlorine as will peroxidize exactly 1000 grain measures, or 100 
 degrees by the test-tube of the copperas solution. But if the manganese contain only 
 40 or 50 per cent, of peroxide, then 40 or 50 centigrade measures of the said solution 
 will be equivalent to the chlorine evolved from it by the re-action of hydrochloric acid. 
 
 If the object is on the other hand to obtain direct indications as to chlorine, then a 
 test solution of copperas, containing 772 grains in 10,000 grain measures, will serve 
 to show, by the peroxidizement of each 1 0 grain measures, or of one degree of the cen- 
 tesimal scale of the test-tube, the re-action of one grain of chlorine available for bleach- 
 ing, &c. in the chloride of lime or of soda, &c. The test solutions of copperas should be 
 kept in well-corked bottles, containing a little powdered sulphuret of iron at their 
 bottom, which is to be shaken up occasionally in order to preserve the iron in the state 
 of protoxide. 
 
 The manganese should always be treated with dilute nitric acid before submitting 
 it to the above-described ordeal ; and if it exhibits effervescence, 100 grains of it should 
 be digested with the acid for a sufficient time to dissolve out all the carbonates present, 
 then thrown upon a filter, washed and dried before weighing it for the testing operation. 
 The loss of weight thereby sustained denotes the per-centage of carbonates, and if cal- 
 careous it will measure the waste of acid that would ensue from that source alone, in 
 using that manganese for the production of chlorine. 
 
 That manganese is most chlorogenous which contains no carbonates, the least pro- 
 portion of oxide of iron, and of sesquioxide of manganese. 
 
 The plan of testing manganese with oxalic and sulphuric acids was originally prac- 
 tised by M. Berthier and Dr. Thomson, but is lately modified by Drs. Fresenius and 
 Will, who employ oxalate of potash, as likely to afford more exact results. They pre- 
 scribe a multiple by 3 of 993 milli-grammes = 2*979 grammes, as the quantity of 
 manganese best adapted to experiment ; but this quantity will not be found convenient 
 by ordinary British operators. 
 
 I, therefore, take leave to prescribe the following proportions : — Into the vessel a 
 of my twin-globe apparatus (Jiff. 185.) put 100 grains of the ground manganese under 
 trial, along with 250 grains of oxalate of potash and a little water ; poise the- whole in 
 the scale of a balance ; then, by gentle inclination, cause a little of the strong sulphuric 
 acid to pass from b up into a. The oxygen thereby liberated from the manganese, 
 reacting in its nascent state upon the oxalic acid, will convert it into carbonic acid gas ; 
 which, in passing through b, will deposit its moisture before escaping into the air. 
 Whenever the extrication of gas ceases, after such a quantity of oil of vitriol has been 
 introduced into the globe a, as both to complete tbe decomposition of the oxalic acid 
 and to heat the mixture, withdraw the cork for a moment, to replace the carbonic acid 
 with air, then cool, and weigh the apparatus. The loss of weight, in grains, will denote 
 the per centage value of the manganese ; that is, the proportion per cent, of perfect 
 peroxide in the sample. If the manganese be pure no black powder should remain. 
 
 The preceding experiment is founded upon the following principle : — One atom of 
 peroxide of manganese = 44, contains one atom of oxygen separable by sulphuric acid, 
 and capable of converting one atom of oxalic acid into two atoms of carbonic acid, 
 also = 44, which fly off ; and cause therefore a loss of weight equal to that of the 
 whole peroxide. To one atom of oxalic acid, which consists of three atoms of oxygen, 
 and two of carbon — if one atom of oxygen be added, the sum is obviously four atoms 
 of oxygen and two of carbon = 2 atoms of carbonic acid. 
 
 The apparatus (Jig. 187.) of Drs. Fresenius and Will will answer perfectly well for 
 making the same experiment, the manganese being put into a, with about two and a 
 half times its weight of oxalate of potash, and the sulphuric acid being drawn over into 
 the mixture by suction, as above described. 
 
 The economy of any sample of manganese in reference to its consumption of acid, in 
 generating a given quantity of chlorine, may be ascertained also by the oxalic acid 
 test : — 44 grains of the pure peroxide, with 93 grains of neutral oxalate of potash, 
 and 98 of oil of vitriol disengage 44 grains of carbonic acid, and afford a complete 
 neutral solution ; because the one half of the sulphuric acid, = 49 grains, goes to form 
 an atom of sulphate of manganese, and the other half to form an atom of sulphate of 
 potash. 
 
 The deficiency in the weight of carbonic acid thrown off will show the deficiency of 
 peroxide of manganese ; the quantity of free sulphuric acid may be measured by a test- 
 solution of bicarbonate of potash, and the quantity neutralised, compared to the car- 
 bonic gas produced, will show, by the ratio of 98 to 44, the amount of acid unprofitably 
 consumed. 
 
 Pp 
 
290 
 
 ALKALIMETRY. 
 
 APPENDIX. 
 
 In Jig-. 183., the tube, d, may also be graduated, and may contain the quantity of 
 acid, for the purpose either of alkalimetry or acidimetry ; and if the lower orifice 
 be capillary, it will allow none of its contents to flow out, till the stopcock in the top 
 orifice is opened. 
 
 In fig. 184., such a tube as d (fig. 183.) may be substituted with advantage 
 for the funnel, b ; and as that tube, d, may be made of such dimensions as to contain 
 enough of acid to supersaturate the bases of the carbonates in the phial, a, there will 
 be no necessity for a separate vessel to hold the decomposing acid. Thus the apparatus 
 becomes very light, convenient, and may be placed in the small scale of a fine balance ; 
 whereas the twin matrasses of Drs. Fresenius and Will, (fig. 187.), as furnished by Mr. 
 Bullock, require a very large pan or scale to stand in. I flatter myself, that the in- 
 strument, fig. 1 84. , so mounted, will be found an acceptable present to practical chemists, 
 and that it will enable them readily to examine, not only carbonates, but also man- 
 ganese and bleaching substances, with great precision, by the weight of carbonic acid 
 gas disengaged, on the principles above explained. 
 
 Into the twin globe apparatus, (fig. 185.), after the sulphuric acid is poured into 
 B, a little water should be poured into c, before the carbonate is introduced into 
 the latter. By this means the capillary throat of the tube under a will not be apt to 
 get choked with concrete salt. 
 
 The following quotations are from the work of Drs, Fresenius and Will, as edited 
 by Mr. Bullock for the English reader. An accurate comparison may thus be made 
 between the relative utility of their methods and mine to the practice of ordinary 
 operators. 
 
 " Section XXXIV. Examination of Manganese : having at the same time due regard 
 to the Amount of Acid required for its complete Decomposition. — We have stated, at 
 Section 30., that it is not a matter of indifference, with regard to the amount of acid 
 employed in the production of chlorine from manganese, what are the minerals which 
 this substance contains in admixture with the peroxide. The following modification of 
 our method will give the most correct information on this point : 
 
 " Sulphuric acid of commerce is taken, and its amount of anhydrous acid deter- 
 mined, as directed at Section 26., or by means of an accurate hydrometer. Of this 
 sulphuric acid as much is weighed into a, (fig. 187.) as to give an amount of 5*47 
 grammes of anhydrous acid. 
 
 " The following table will show the amount which ought to be taken, according to 
 the various degree of concentration of the acid : 
 
 Specific weight 
 found. 
 
 Percentage 
 amount of 
 Anhydrous 
 Acid found. 
 
 Amount to 
 be used for 
 the examin- 
 ation. 
 
 Specific weight 
 found. 
 
 Percentage 
 amount of 
 Anhydrous 
 Acid found. 
 
 Amount to 
 be used for 
 the examin- 
 ation. 
 
 1-8485 
 
 81-54 
 
 6-708 
 
 1 -8336 
 
 76-65 
 
 7-136 
 
 1 -8480 
 
 81-13 
 
 6-742 
 
 1-8313 
 
 76-24 
 
 7-174 
 
 1-8475 
 
 80-72 
 
 6-776 
 
 1-8290 
 
 75-83 
 
 7-213 
 
 1 -8467 
 
 80-31 
 
 6-811 
 
 1-8261 
 
 75-42 
 
 7-252 
 
 1 -8460 
 
 7990 
 
 6-846 
 
 1 -8233 
 
 75-02 
 
 7-291 
 
 1 -8449 
 
 79-49 
 
 6-881 
 
 1 -8206 
 
 74-61 
 
 7-331 
 
 1-8439 
 
 79-09 
 
 6-916 
 
 1-8179 
 
 74-20 
 
 7-371 
 
 1 -8424 
 
 78-68 
 
 6-951 
 
 1-8147 
 
 73-79 
 
 7-412 
 
 1-8410 
 
 78-28 
 
 6*987 
 
 1-8115 
 
 73-39 
 
 7-453 
 
 1-8393 
 
 77-84 
 
 7 027 
 
 1-8079 
 
 72-97 
 
 7-495 
 
 1-8376 
 
 77-40 
 
 7-067 
 
 1 -8043 
 
 72-57 
 
 7'537 
 
 1-8356 
 
 77-02 
 
 7-101 
 
 
 
 
 " As much water is then poured into a as will fill the flask to about one-fourth ; 
 and, lastly, from 6-5 to 7 grammes of neutral oxalate of potash, or from 5*5 to 6 
 grammes of neutral oxalate of soda, are added ; 2*98 grammes of the (finely-pounded) 
 manganese to be examined are then weighed (the manganese must have been pre- 
 viously tested for carbonate alkaline earths : compare this section at the end) into a 
 small glass tube, such as used in acidinaetry, and described in Section 25. About the 
 same quantity of pure pyrolusite *, in powder, is then put into another similar tube. 
 The tube, with the manganese to be examined, is then suspended in a (fig. 187.), as 
 described at Section 26., and the apparatus prepared, as directed at Section 3. The 
 
 * " Any variety of pyrolusite will serve this purpose, provided it be free from other manganese ores. If 
 it contains heavy spar, it may be employed directly ; but should it contain alumina or lime, it must be 
 treated first with dilute nitric acid, at a gentle heat, until all soluble parts have been dissolved ; it is 
 then washed and dried. Artificially prepared, hydrated peroxide of manganese may be substituted for 
 
APPENDIX. 
 
 ALKALIMETRY . 
 
 291 
 
 apparatus is then placed on one scale of a balance, together with the other little tube 
 containing the pyrosulite, and exactly weighed. 
 
 " The cork of a is then somewhat raised to allow the little tube with the manganese 
 to fall into the flask. The evolution of carbonic acid commences immediately, and 
 continues until all the manganese is decomposed. When the operation begins to get 
 on more slowly, the flask, a, is placed in boiling water, and allowed to remain there 
 until no more bubbles appear. The little wax-stopper is then removed * from cr, the 
 flask, a, taken out of the hot water, and suction applied to d, until the sucked air 
 tastes no longer of carbonic acid. The apparatus, after having been allowed to cool, 
 is wiped dry, and replaced in the original scale, where the little tube with the pyro- 
 lusite still remains ; weights are then substituted for the loss of carbonic acid. The 
 number of centigrammes required, divided by three, directly indicates the per centage 
 amount of peroxide of manganese (vide Section 32.). The centigrammes substituted 
 for the loss of carbonic acid are then removed from the balance, and the little tube 
 with the pyrosulite is thrown into a. (The little wax-stopper must of course pre- 
 viously be replaced on a). If no fresh evolution of carbonic acid takes place, the 
 manganese examined consists of pure pyrosulite, and the experiment is at an end. But 
 should a fresh evolution of carbonic acid take place, the operation must be further 
 conducted, and brought to a close, exactly as just stated (vide supra). The apparatus 
 is then replaced on the balance, with an additional weight of three grammes on the 
 same scale. If this is sufficient to restore a perfect equilibrium, no loss of acid has 
 taken place ; the manganese, indeed, contains other matters in admixture, but only 
 such as do not consume any acid. But if the scale with the apparatus sinks, this is a 
 certain sign that a portion of the acid has been lost by combining with the oxides which 
 the manganese under examination contains. The number of centigrammes required 
 to restore the perfect equilibrium of the balance, multiplied by 0*6114, immediately 
 indicates how much anhydrous sulphuric acid has been wasted in the decomposition of 
 100 parts of the manganese under examination. The same number, multiplied by 
 0*333, indicates the amount of acid wasted in every 100 parts of sulphuric acid em- 
 ployed for the decomposition of the manganese in question. The same number, multi- 
 plied by 0*5552, indicates how much anhydrous hydrochloric acid would be wasted in 
 the decomposition of 100 parts of the manganese. The same number, multiplied by 
 0*333, indicates also how much acid would be wasted in every 1 00 parts of hydro- 
 chloric acid employed for the decomposition of the manganese. 
 
 " These figures result from the following equations : 
 " I. 275 (eq. of carbonic acid) : 501 (eq. of sulphuric acid) = the carbonic acid ob- 
 tained minus (in proportion to the sulphuric acid used) : x. 
 
 x = this carbonic acid x i. e. x 1*822. 
 Thus, the number obtained for x indicates the amount of sulphuric acid correspond- 
 ing to the amount of carbonic acid obtained minus. 
 
 "II. 2*98 of manganese : 100 = a; of equation I. : x. 
 x = x of I. x i. e. x 0*33557. 
 " The x of the first equation tells us how much sulphuric acid has been wasted 
 without contributing to the decomposition of 2*98 grammes of the manganese; the x 
 of the second equation tells us the same for 100 parts of manganese. 
 
 " If, therefore, the amount of carbonic acid obtained minus be directly multiplied by 
 the product of the quotients of I. and II., 
 
 1-822 and 0*33557, 
 
 i. e. with 0*61141 (the number given above), the amount of anhydrous sulphuric acid 
 wasted in the decomposition of every 100 parts of manganese will immediately be 
 found. 
 
 " III. 5*47 (the amount of sulphuric acid used) : 
 100 = the x of I. : x. 
 x = the x of I. x i. e. x 0-18282. 
 " Of 5*47 of sulphuric acid, the x of I. has been wasted, 100 corresponds to the x 
 of III. 
 
 " The x of III. is, therefore, found directly by multiplying the amount of carbonic 
 acid obtained minus with the product of the quotients, 1*822 and 0*18282, i. e. = 
 0*33301. 
 
 " The figures for hydrochloric acid are found in the same manner (4*967 of hydro- 
 chloric acid must be taken instead of 5*47 of the sulphuric acid)."f 
 
 * " This must of necessity be done while the flask is still standing in the hot water, or else the sul- 
 phuric acid will recede upon the apparatus being removed from the hot water." 
 
 t New Methods of Alkalimetry, and of determining the Commercial Value of Acids and Manganese. 
 By Drs. C. R. Fresenius and H. Will. Edited by J. Lloyd Bullock. Pp. 12J-128. 
 
 P p 2 
 
292 
 
 FLAX. 
 
 APPENDIX. 
 
 BEER. A gentleman well acquainted with the brewing of porter in London has 
 favoured me with the following information. 
 
 Essentia Vina has been discontinued by the London porter brewers since the employ- 
 ment of black malt, which is prepared by roasting in such a cylinder as coffee is usually 
 roasted in over a fire. A peculiar flavour has sometimes been imparted by using 
 roasted barley instead of malt. The usual quantity of yeast employed in the London 
 porter breweries is from 5 to 7 tenths per cent. The grist, as it is technically termed, 
 or charge for a mash-tun, is composed of from § to § pale malt, and the rest of high 
 dried malt, of which about from ^ to black. The oil of birch bark is not used by 
 any respectable brewers in this country. The proportion of hops for double stout is 
 seldom more than 15 pounds to the 8 bushels of malt. 
 
 FLAX. The new roving machine, called by the ingenious inventor, Mr. W. K. 
 Westley, of Leeds, the Sliver Roving Frame, seems to be a philosophical induction 
 happily drawn from the nature of the material itself, and accommodated to its peculiar 
 constitution. It is remarkable for the simplicity of its construction, and, at the same 
 time, for its comprehensiveness ; requiring no nicety of adjustment in its application, 
 and no tedious apprenticeship to be able to work it. 
 
 It is known, that the glutinous matter of the plant may be softened by water, and 
 hardened again by heat ; of this fact advantage is taken, in order to produce a roving 
 wholly without twist ; that is, in the form of a ribbon or sliver, in which the fibres are 
 held together by the glutinous matter which may be natural to them; or which may, 
 for that purpose, be artificially applied. The sliver roving, as long as it remains dry, 
 possesses all requisite tenacity, and freely unwinds from the bobbin, but on becoming 
 again wetted in the spinning frame, it readily admits, with a slight force, of being 
 drawn into yarn, preserving the fibres quite parallel. 
 
 The diagram, fig. 190., shows in explanation, that 
 
 A, is the drawing roller of the roving 
 frame in front of the usual comb. 
 
 B, the pressing drawing roller. 
 
 C, a shallow trough of water. 
 
 D, a cylinder heated by steam. 
 
 E, a plain iron roller for winding. 
 
 F, a bobbin lying loose upon the 
 winding roller, and revolving upon it, 
 by the friction of its own weight. 
 
 The roving, or sliver, as shown by 
 the dotted line, after leaving the draw 
 ing rollers A B, passes through the 
 water, in the trough C, which softens 
 the gluten of the fibres; and then it is 
 carried round by the steam cylinder D, 
 which dries it, and delivers it hard and 
 tenacious to the bobbin F, on which it 
 is wound by the action of the roller E. 
 This is the whole of the mechanism required in producing the sliver roving. All 
 the complex arrangements of the common cone roving are superseded, and the machine 
 at once becomes incomparably more durable, and easier to manage ; requiring only 
 half the motive power, and occupying only half the room. A frame of 48 bobbins is. 
 only G feet long, and affords rovings sufficient to supply 1200 spinning spindles. 
 
 190 
 
APPENDIX. 
 
 FLAX. 
 
 293 
 
 The machine is very general in its application, being equally well adapted for heavy 
 as for fine rovings. 
 
 In making a roving in the usual way, the twist, in addition to other circumstances, 
 sets a limit to the degree to which a material of a given fineness may be roved • be- 
 cause the quantity of twist required to give a roving the necessary cohesion, increases 
 in proportion as the number of fibres composing that roving diminishes, till it 
 accumulates to such a degree, that the fibres are prevented from drawing regularly, 
 or, if drawn, are broken and scattered by the violence of the action. It is impos- 
 sible, therefore, to make a light roving, good for any thing, out of a coarse material ; 
 but in the sliver roving, there is no difficulty in making a roving of almost any 
 fineness, with little reference to the quality of the material employed, because, while 
 one fibre can be glued to another by any portion of its extremity, a roving may 
 be made. 
 
 It becomes easy, with a sliver roving, to use a double or triple roving on the spin- 
 ning frame. The great advantage of this practice has long been well known, and 
 acted upon, in the spinning of cotton ; but in that of flax, it has hitherto been un- 
 attainable : yet the vast benefit to be expected, from doubling on the spinning 
 frame all the equalisation of the previous preparation, is too self-evident to be insisted 
 upon. 
 
 The sliver roving, made however fine, is perfectly solid, tenacious, and compact ; no 
 fibres in it, when once laid straight, can afterwards be ruffled or disturbed ; and, as 
 they are placed in the yarn in the exact position in which they leave the combs, being 
 kept straight without any ruffling or tangling from twist, the inelastic nature of the 
 material is not injured, and the yarn acquires a superior lustre, roundness, and 
 strength. 
 
 The sliver roving is drawn with less force than the twisted roving, and is therefore 
 less liable to make snarls in the yarn ; while it has another advantage arising from the 
 absence of twist. The fibres of flax and tow being various in length, an uniform twist 
 upon them will naturally retain the longer fibres more effectually than the shorter 
 ones, which will hence have a tendency to run into thick places in the yarn. From 
 this inconvenience the sliver roving is completely free. 
 
 In the spinning frame, there is also a benefit derived from the bruising action of the 
 detaining roller : the pressure is supposed to split the fibres laterally, and thereby make 
 them finer, in the same way as a board would be split by being passed through iron 
 rollers, under a pressure ; but it is evident that in a twisted roving a portion of each 
 fibre must escape this action, by winding round the body of the roving, and, con- 
 sequently, the fibres can be but partially split. By this circumstance, in addition to 
 the direct loss of benefit, a new and serious evil is created ; a fibre split has always, in 
 the split portion, one end longer than another, and the longest end, of course, arrives 
 first at the drawing rollers. Now, if the fibre be only partially split ; if that portion 
 whose end arrives first be not wholly separated from the rest of the fibre ; it follows, 
 that when the longer end is seized by the drawing rollers, the shorter end will be drawn 
 into a knot, or thickening ; because its fore end is still held back by the adhesion of its 
 contiguous fibres, while its back end is drawn forwards, by being still attached to its 
 original fibre. In the sliver roving, the fibres, being perfectly straight and parallel, are 
 exposed to the bruising of the rollers equally, and are split uniformly and entirely from 
 end to end. 
 
 The sliver roving, being so much simpler in construction than any other, is capable 
 of running quicker ; but if running only at the same speed, it will produce from 25 to 
 30 per cent, more work, because it is never stopped in order to be doffed. The bobbins 
 are so placed, that the attendant has only to remove a filled bobbin, and replace it with 
 an empty one, without the slightest interruption to the progress of the machine. 
 Owing to this circumstance, the attendant is provided with an easy and uniform em- 
 ployment for her time, instead of occasionally doing nothing, and again hurrying 
 through the labour of doffing ; and the work also, being simpler, may be performed by 
 cheaper hands. 
 
 It must be noted that doffing is of frequent occurrence, especially in heavy numbers, 
 and occupies much time where one person has to doff a great many spindles, and it is often 
 inconvenient, where other hands are called from their work to assist : but it is not only 
 in doffing that time is lost ; it is in wiping, picking, and oiling the numerous flyers 
 and spindles carefully, and which should not be hurried ; and, moreover, when the 
 machine requires thorough cleaning, the complication of its mechanism materially in- 
 creases the loss of time as well as expense ; so that the saving effected by not stopping 
 the frame to doff becomes very considerable, and soon repays the whole cost of the 
 machine. 
 
294 
 
 FLAX. 
 
 APPENDIX. 
 
 Each bobbin has, in fact, its own regulating motion, independent of the rest ; and 
 this is at all times correct, without requiring any fresh adjustment or adaptation to 
 different thicknesses of roving, enabling the spinner to rove at the same time, on 
 the same frame, as many sorts or thicknesses of roving as there are bobbins in a 
 frame ; whereas on the common machine he is compelled to rove but one sort or 
 thickness at a time ; and whenever he alters the sort, the mechanism requires a fresh 
 adjustment, involving the chances of error, and attended with loss of time and waste of 
 material. 
 
 THE END. 
 
 London : 
 Printed by A. Spottiswoodr, 
 New-Street- Square. 
 
APPENDIX 
 
 TO 
 
 THE SECOND EDITION 
 
 or THIS 
 
 SUPPLEMENT. 
 
 AMYGDALTNE is a principle of bitter almonds and of bay-laurel berries. It is 
 obtained by digesting, in a retort, alcohol of 0*825 at its boiling temperature upon the 
 meal of bitter almonds, then distilling off the alcohol by the heat of a water-bath till 
 the residuum assumes the consistence of syrup. To the residuum, diluted with a 
 little water, some yeast is to be added, and the mixture is to be set aside in a warm 
 place for some time to ferment. Whenever the fermentation is over the liquor is to 
 be filtered, and evaporated on the water-bath to a syrupy consistence. On mixing this 
 syrup with alcohol of 0"825 the amygdaline falls in a white crystalline powder, which, 
 after being squeezed between folds of filtering-paper, is to be finally purified, by 
 repeated crystallizations, with alcohol. Its crystals are silky-looking scales, or short 
 needles, without smell, but with a slight taste of bitter almonds. When heated they 
 exhale the fragrance of hawthorn flowers, and burn into a bulky charcoal. Cold alcohol 
 hardly dissolves them, but boiling alcohol pretty copiously. They are very soluble in 
 water, and produce therefrom by evaporation and cooling large transparent prisms, of a 
 silky aspect, which contain 6 atoms, or 10*57 per cent, of water. Their composition 
 in the dry state is as follows : — 
 
 40 atoms of carbon - - - , 52*98 in 100 parts. 
 
 27 — hydrogen - 5*84 — 
 
 1 — azote - - - 3*06 — 
 
 22 — oxygen - r - 38.12 — 
 
 1 atom amygdaline (Liebig) - 100*00 
 
 The purpose of the fermentation above prescribed is to decompose a portion of 
 sugar, extracted by the alcohol from the bitter almonds along with the amygdaline, 
 of which latter they afford from 3 to 4 per cent. 
 
 Almonds, both bitter and sweet, contain also another curious principle, called 
 emulsine by Liebig, and synaptase by Robiquet. It is soluble in water, but is pre- 
 cipitated from it in flakes by alcohol. It coagulates at the temperature of about 
 140° Fahr. like white of egg. On mixing a solution of 10 parts of amygdaline in 100 
 parts of water, with 1 part of synaptase in 10 parts of water, a peculiar decomposition 
 immediately takes place. The mixture becomes opaline without losing its transparency ; 
 it assumes the odour of bitter almonds, and yields, on distillation, hydrocyanic (prussic) 
 acid, and the hydrure of benzoil (pure essence of bitter almonds), mixed with vapours 
 of water. Coagulated synaptase has no perceptible action on amygdaline. These facts 
 explain a series of puzzling phenomena, which have been long known. Fresh bitter 
 almonds contain emulsine (synaptase), amygdaline, and an unctuous oil, all in such 
 a state that the first two cannot react upon each other ; and by removing the water by 
 desiccation their mutual action becomes impossible. On squeezing the almonds the 
 oil is drawn out, and on treating the cake with boiling alcohol the amygdaline is 
 
296 ARSENICAL POISON, DETECTION OF. appendix n. 
 
 Fig. 191. 
 
 dissolved out, and the synaptase is coagulated ; but on moistening the bitter almonds 
 with water, the reaction of the two principles becomes instantly effective, as shown by 
 the production of the smell and taste of hydrocyanic acid and of the essential oil. 
 By throwing the bitter almond meal into boiling water the synaptase immediately 
 coagulates, and the above mutual reaction can no longer be obtained, nor the above vola- 
 tile products. In order properly to prepare the essence of bitter almonds it is therefore 
 necessary to mix 1 part of bitter almond meal with 20 parts of lukewarm water, to 
 leave the mixture to digest for 24 hours, and only then to submit it to distillation. 
 100 parts of amygdaline produce 47 parts of the crude essence of bitter almonds, which 
 contain 5*9 parts cf hydrocyanic acid. 
 
 ARSENICAL POISON, DETECTION OF. It is well known that fluids 
 mixed with glutinous matter are very liable to froth up when hydrogen is disengaged 
 in them from the mutual action of zinc and a dilute acid ; and that the froth obstructs 
 the due performance of the experiment of Marsh. It is equally known, that much of 
 the arsenic contained in the poisonous liquid so tested, escapes condensation and eludes 
 measurement. A committee, appointed by the Prussian government, have contrived 
 an ingenious modification of Marsh's apparatus, which I have simplified into the 
 
 annexed form : — a, is a narrow glass cy- 
 linder, open at top, about 10 inches high, 
 and 1^ or 11 inch diameter inside ; B is a 
 glass tube, about 1 inch diameter outside, 
 drawn to a point at bottom, and shut with 
 a cork at top. Through the centre of this 
 cork, the small tube c passes down air- 
 tight, and is furnished at top with a stop- 
 cock, into which the bent small tube of 
 glass (without lead) e is cemented. The 
 bent tube f is joined to the end of e 
 with a collar of caoutchouc, or a per- 
 forated cork, which will be found more 
 convenient. 
 
 The manner of using this apparatus is 
 as follows : — Introduce a few oblong 
 slips of zinc, free from arsenic, into b, 
 and then insert its- air-tight cork with 
 the attached tubes. Having opened the 
 stop-cock, pour into a as much of the 
 suspected liquid, acidulated with dilute 
 hydrochloric or sulphuric acid (each pure) 
 as will rise to the top of the cork, after b 
 is full, and immediately shut the stop- 
 cock. The generated hydrogen will force 
 down the liquid out of the lower orifice 
 of b into a, and raise the level of it 
 above the cork. The extremity of the 
 tube f being dipped beneath the surface 
 of a weak solution of nitrate of silver, and a spirit flame being placed a little to 
 the left of the letter e, the stop-cock is then to be slightly opened, so that the gas 
 which now fills the tube b may escape so slowly as to pass off in separate small bubbles 
 through the silver solution. By this means the whole of the arsenic contained in the 
 arseniuretted hydrogen will be deposited either in the metallic state upon the inside of 
 the tube e, or with the silver into the characteristic black powder. The first charge 
 of gas in b being expended, the stop-cock is to be shut, till the liquid be again expelled 
 from it by a fresh disengagement of hydrogen. The ring of metallic arsenic deposited 
 beyond e may be chased onwards by placing a second flame under it, and thereby formed 
 into an oblong brilliant steel-like mirror. It is evident, that by the patient use of this 
 apparatus the whole arsenic in any poisonous liquid may be collected, weighed, and 
 subjected to every kind of chemical verification. If p be joined to e by means of a 
 perforated cork, it may readily be turned about, and its taper point raised into a posi- 
 tion such as when the hydrogen issuing from it is kindled, the flame may be made to 
 play upon a surface of glass or porcelain, in order to produce the arsenical mirror. 
 
 Or, the preceding process may be made supplementary to that of boiling the arseni- 
 cal foul liquor, acidulated with hydrochloric acid upon slips of clean copper, whereby 
 the arsenic is precipitated upon the copper in a metallic film, or thin crust more or less 
 brilliant. If one of the slips of copper thus coated be placed in the tube b of the 
 above-described apparatus, it will give off its arsenic without the annoyance produced 
 by the frothing up of a glutinous mixture. 
 
appendix it. DAGUERREOTYPE PRINTING. 
 
 297 
 
 DAGUERREOTYPE PRINTING; or transformation of the Daguerreotype 
 picture into an engraved plate fit for the printing press. An invention for this purpose, 
 as invented by a foreigner not named, was made the subject of a patent by Mr. Claudet 
 in 1843. 
 
 The process is divided into two parts, consisting of a preparatory and finishing 
 operation. 
 
 Preparatory Engraving. — For this operation, which is the most delicate, it is ne- 
 cessary to have, 1. A saturated solution of caustic potash. 2. Pure nitric acid at 36° 
 of the areometer of Beaume (spec. grav. 1 *333). 3. A solution of nitrite of potassa, 
 composed of 100 parts of water and 5 parts of nitrite, by weight. 4. A solution of 
 common salt, composed of water 100 parts, and salt 10 parts, by weight. 5. A weak 
 solution of ammoniacal chloride of silver, with an, excess of ammonia. The ammoniacal 
 chloride of silver must be diluted with 15 or 20 parts of pure water. In the descrip- 
 tion of the process, this solution will be called ammoniacal chloride of silver. 6. A 
 weak solution of ammonia, containing 4 or 5 thousandths of liquid ammonia. This 
 solution will be called ammoniacal water. 7. A weak solution of caustic potash, con- 
 taining 4 or 5 thousandths of the saturated solution, which will be called alkaline 
 water. 8. A solution composed of water 4 parts, saturated solution of potash 2 parts, 
 alcohol 1 part, all in volume. This solution will be called alcoholised potash. 
 9. Acidulated water, composed of water 100 parts, and nitric acid 2 parts, in volume. 
 Besides, it is necessary to have three capsuke or dishes, made of porcelain, large enough 
 to contain the plate, and covered with an air-tight piece of ground plate-glass, and two 
 or three more capsules, which do not require to be eovered ; two or three glass funnels, 
 to wash the plate ; and two or three glass holders, in the shape of a spoon or shovel, 
 by which the plate is supported when put in and taken out of the solution, without 
 touching it with the fingers. 
 
 The Daguerreotype plate is submitted to the engraving process, after having been 
 washed in the hyposulphite of soda, and afterwards in distilled water. 
 
 First process for biting in or engraving the Plate. — Ihe following solutions must be 
 put in the capsules, in sufficient quantity, so as to entirely cover the plate : — 1. Acid- 
 ulated water. 2. Alkaline water. 3. Alcoholised potash, in covered capsules. 4. Caus- 
 tic potash, in covered capsules. 5. Distilled water. 
 
 The plate being put upon the glass holder or spoon, is plunged in the acidulated 
 water, and agitated during a few seconds, then put into a glass funnel, and washed with 
 distilled water. It is taken again with the glass spoon, and plunged in the capsule 
 containing alcoholised potash. This capsule is covered with its glass cover, and then 
 heated, by means of a spirit-lamp, to about 144° Fahrenheit. The plate must remain 
 in the capsule half an hour, during which the solution is heated now and then, and 
 agitated. During that time the following acid solution, which will be called normal 
 acid, must be prepared ; it is composed as follows : — Water 600 parts, nitric acid 
 45 parts, solution of nitrite of potassa 12 parts, solution of common salt 45 parts. 
 These proportions are in volume. The normal acid must be poured into a capsule, 
 covered with its glass cover, and a sufficient quantity must be kept in the bottle. 
 
 When the plate has been immersed in the alcoholised potash during half an hour, 
 it is taken out of the solution by means of the glass holder, and immediately plunged 
 in the alkaline water, and agitated pretty strongly; from thence it is put in distilled 
 water. (A) 
 
 This being done, the plate is plunged in the acidulated water, and moved about 
 therein for a few seconds : it is then put into the normal acid. When the plate has 
 been immersed a few seconds in the acid, it is taken out by means of the glass 
 holder, taking care to keep it as much as possible covered with the solution, and it 
 is immediately placed horizontally upon a stand, and as much acid as the plate can 
 hold is poured upon it from the bottle : it is then heated with a spirit-lamp, but 
 without attaining the boiling point. During this operation it is better to stir or 
 move about the acid on the plate by pumping it, and ejecting it again, by means of a 
 pipette or glass syringe; after two or three minutes the acid is thrown away, the plate 
 is put in the glass funnel, and there well washed with water, and afterwards with dis- 
 tilled water. (B) 
 
 Then, without letting the plate dry, it is put upon the fingers of the left hand, and 
 with the right hand some ammoniacal chloride of silver, which is moved about the sur- 
 face by balancing the hand, is poured upon it; the solution is renewed until the chloride, 
 formed by the action of the acid, is dissolved ; the plate is then washed by pouring upon 
 it a large quantity of ammoniacal water, and afterwards some distilled water. (C) 
 
 Without allowing the plate to dry, it is then put in the caustic potash, and the capsule 
 being placed upon the stand, the potash is heated up to the boiling point ; it is then left 
 to cool(D); and beginning again the operations described from A to D, a second 
 biting is obtained ; and by repeating again the operations described in A and B, a 
 
 Q q 
 
298 
 
 DAGUERREOTYPE PRINTING. appendix il 
 
 third biting is produced. The plate is then dried ; in this state the black parts of the 
 plate are filled with chloride of silver. 
 
 The plate is then polished until the white parts are perfectly pure and bright. 
 This polishing is done with cotton and " ponce " (pumice stone); afterwards, the 
 chloride of silver, filling the black parts, is cleansed by the means described in B and 
 C. The plate is dried, but before drying, it is well to rub the plate slightly with the 
 finger, in order to take off from the black parts any remains of an insoluble body, which 
 generally stick to it. The preparatory engraving is then finished, and the plate has the 
 appearance of a very delicate aquatint engraved plate, not very deeply bitten in. 
 
 Nevertheless, if the operation has been well managed, and has been successful, it is 
 deep enough to allow the printing of a considerable number of copies. 
 
 Note. — Sometimes, instead of treating the plate with the boiling potash in the 
 capsule, a similar result may be obtained by placing the plate upon the sand, covering 
 it with the solution, and heating it by means of a spirit lamp, until, by evaporation, the 
 potash passes into a state of ignited fusion. By this means the grain is finer, but the 
 white parts are more liable to be attacked. 
 
 Last operation of biting in. — This operation requires some of the re-agents before 
 named, and also, 
 
 1. A siccative ink, made of linseed oil, rendered very siccative by boiling it suffi- 
 ciently with litharge ; it may be thickened with calcined lamp-black. 
 
 2. An electrotype apparatus, and some solutions fit to gild, and copper the plate. 
 Means of operating. — The plate must be inked as copper-plate printers do, taking 
 
 care to clean off the white parts more perfectly than usual ; the plate is then to be 
 placed in a room sufficiently warm, until the ink is well dried, which requires more or 
 less time, according to the nature of the oil employed. The drying of the oil may be 
 hastened by heating the plate upon the stand with the lamp, but the slow process is 
 more perfect and certain. 
 
 When the ink is well dried, the white parts are cleaned again, by polishing the 
 plate with cotton and ponce, or any other polishing powder : a ball of cotton, or any 
 other matter, covered with a thin piece of caoutchouc or skin, can be used for this pur- 
 pose. When polished, the plate is ready to receive the electro-chemical coating of 
 gold, which will protect the white parts. 
 
 Gilding. — The gilding is obtained by any of the various processes of electrotyping 
 which are known. The only indispensable condition is, that the surface obtained by 
 the precipitation must not be liable to be attacked by any weak acid; a solution 
 answering this purpose is made of 10 parts (by weight) of ferrocyanide of potassium, 
 1 part of chloride of gold, and 1000 parts of water, used with a galvanic battery. 
 During the gilding the plate must be turned in several positions, in order to regulate 
 the metallic deposit. In some cases the gilding may be made more perfect, if the plate 
 is covered with a thin coating of mercury before being put in the gilding solution. 
 
 When the plate is gilded, it must be treated with the boiling caustic potash, by the 
 process already indicated for the preparatory engraving, in order to cleanse it from all 
 the dried oil or ink, which fills the hollows. The plate is then washed and dried, and 
 when the oil employed has been thickened with the lamp-black, the surface of the plate 
 is rubbed with crumb of bread, in order to cleanse and take off the black remaining ; 
 then the white parts being covered and protected by a varnish not liable to be attacked, 
 and the black parts being uncovered and clean, the plate can be bitten in by aquafortis, 
 according to the ordinary process used by engravers. 
 
 This operation must be done upon the stand, and not by immersing the plate in the 
 solution. 
 
 Before this last biting-in, if the preparatory engraving has not succeeded well, and 
 the plate still wants a sufficient grain, it can be given by the various processes of 
 aquatint engraving. 
 
 Before submitting the plate to the operation of printing, in order to ensure an unli- 
 mited number of copies, it is necessary, as before stated, to protect it by a slight coating 
 of copper, which is obtained by the electrotype process ; otherwise the printing would 
 soon wear the plate. This coating must be kept very thin, lest the fineness of the 
 engraving, and the polish of the white parts, should be destroyed. In this state the 
 plate can be delivered to the printer. 
 
 After a certain number of impressions have been obtained, it will be perceived that 
 the coating of copper is worn in some places : then this coating must be removed, and 
 a fresh one applied in its place. For this purpose the plate must be purified and 
 cleansed by warm potash, and plunged in a weak acid, composed as follows : — Water, 
 600 parts ; nitric acid, 60 parts ; nitrous acid of engravers, 5 parts ; all in volume. 
 This acid will dissolve the coating of copper, and the plate being coppered again, by 
 the same means as before, may be again submitted to the operation of printing ; and as 
 nothing can prevent the success of a repetition of the same operation, any number of 
 
APPENDIX II. 
 
 GUANO. 
 
 299 
 
 impressions may be obtained. The coating of copper can also be removed by caustic 
 ammonia. 
 
 The Daguerreotype plate engraved by this process may be also reproduced and mul- 
 tiplied by the electrotype process, the same as any other engraved plate. 
 
 The essential points of this process, which constitute the present invention, consist, — 
 
 First, in the discovery and employment of certain properties of a mixture composed 
 of nitric acid, nitrous acid, and hydrochloric acid, in determined or fixed proportions. 
 The two last-mentioned acids may be employed either in a free state, or combined with 
 alkaline or other bases. This mixed acid has the property of biting the pure silver, 
 which forms the black parts of the Daguerreotype picture, without attacking the white 
 parts formed by the amalgam of mercury. The result of the action of the biting is, to 
 form on the black parts of the picture an insoluble chloride of silver; and this chloride 
 of silver, which, when formed, stops the action of the acid, is dissolved by ammonia, 
 which allows the biting to continue. 
 
 Secondly, in the discovery of certain properties of a warm solution of caustic potash, 
 and in the employment of the said solution, by which the mercury forming the picture 
 is better and deeper amalgamated with the silver under it, so that many imperceptible 
 points of the amalgam are affected in such a manner that the acid has no action upon 
 them. 
 
 Thirdly, in the discovery and employment of a process which produces a grain 
 favourable to the engraving, by which the biting on the plate is rendered deeper. This 
 is effected by filling the parts engraved with a siccative ink, or any other substance, and 
 then gilding the plate by the electrotype process : the gold is not deposited on the 
 parts protected by the ink. When the plate is gilded, the ink is cleansed by the caustic 
 potash, and the plate may be submitted to the effect of an acid, which does not attack 
 the coating of gold, but bites only on the silver in the parts already engraved by the 
 first operation. 
 
 Fourthly, in the employment of a process by which the plate is protected from the 
 wear of the printing operation. This is effected by covering the plate, before printing, 
 with a slight coating of copper, by the electrotype process, and when the coating begins 
 to wear, by printing, it is removed by a weak acid, or by ammonia, which dissolves the 
 copper without affecting the silver under it. The plate is coppered again, and after 
 another printing the same operation is repeated, so that a considerable number of copies 
 maybe printed without much injury to the engraving. — Newton's Journal, C. S.xxv. 111. 
 
 DYEING. A patent was obtained in 1840 by Mr. Charles Kbber for fixing colours 
 better in wool and woollen cloth, by boiling them first of all in a weak solution (about 
 3 pounds to 100 of scoured wool) of bichromate of potash, along with about 2 pounds 
 of argal, for an hour and a half; and next day dyeing them of any colour in the usual 
 way. He produces a fast green by dyeing the wool blue, making it into cloth, and 
 then dyeing this yellow, by fustic, with a mordant consisting of 6 or 7 pounds of a 
 solution of muriate of tin, specific gravity 1 "2612 or 30° Baume, along with alum and 
 argal. He prepares his indigo blue vat, with soda, lime, and bran, instead of woad, 
 madder and bran, as usually employed. 
 
 GAS-METER. The difficult problem of a good dry gas-meter has been at length 
 solved by Messrs. Croll and Richards, in their recently obtained patent invention. I 
 am of opinion, that it is a perfect philosophical instrument, both in principle and per- 
 formance ; capable of measuring the consumption of coal gas with geometrical pre- 
 cision, and free from all the fallacies to which several of the water gas-meters are 
 liable. This new gas-meter is a drum with flat discs, which have a direct and not an 
 angular motion, and is on that account preferable to any dry meter with which I 
 am acquainted. 
 
 GLASS. A fine red colour may be given to glass by combining with it in the 
 melting-pot a small portion of a|sulphuret'of chromium, containing one atom of sulphur 
 to two of the metal. Dr. Kopp, the author of this statement, does not say precisely 
 how this peculiar sulphuret is to be formed ; for the common sulphuret contains 3 
 atoms of sulphur to 2 of the metal. It would seem to be by a partial decomposition of 
 the sulphate of chromium. 
 
 GUANO. Since I wrote the memoir on guano in this Supplement, very large 
 importations have been made from the coast of Africa, especially from the island of 
 Ichaboe, and of very various qualities, as will appear from the several analyses which 
 have been published, as made by other chemists as well as myself. Of many of these 
 analyses it may be remarked that they are quite defective, in not determining the 
 amount of azotised animal matter, or of its equivalent potential ammonia — a con- 
 stituent of guano of the first-rate value, being that which promotes the fertility of soil 
 for several years, whereas the actual ammonia in the saline state is apt to be speedily 
 wasted by the sun and rains, and can be considered therefore as food for only one season. 
 My attention was first strongly drawn to these imperfect analyses by the report of one 
 
 Q q 2 
 
300 
 
 GUANO. 
 
 APPENDIX H. 
 
 made by Professor Johnston upon a guano of which a sample was also put into ray- 
 hands for analysis by the importers, Messrs. Anthony Gibbs and Sons, of London, 
 The cargo was imported from Peru by the Providence, towards the end of last August. 
 Professor Johnston's statement is a& follows : — 
 
 " Water, and volatile ammonia - - - - 5-24 
 
 Organic matter, and ammoniacal salts - 58*00 
 
 Salts soluble in water, consisting of sulphate and muriate of soda 6 "37 
 Insoluble siliceous matter - - - - - 1 -07 
 
 Phosphate of lime, and a little phosphate of magnesia - - 25 "37 
 
 Carbonates of lime, magnesia, &c. - - - - 3*95 
 
 100-00 " 
 
 Fy this analysis we can form no idea of the quality of the guano, because the pro- 
 portion of ammonia, whether actual or potential, is not stated ; and we are therefore 
 left as much in the dark about the marketable or agricultural value of the article as we 
 should be of a cargo of rum, of which the excise proof specific gravity, or proportion of 
 alcohol, was not given. The determination of the precise amount of ammonia is one 
 of the nicest parts of the analysis — one which may be regarded as quite indispensable, 
 and without which the cost of an analysis should not be more than ten shillings, if that 
 of the more complete analysis, including the proportion of the actual and potential 
 ammonia, be two guineas, which is my general fee. As to the carbonate of lime and 
 magnesia, I entirely doubt the accuracy of the analysis, since I found neither of them 
 in it, nor in any genuine excrement of sea-birds which I have had occasion to examine. 
 In fact, the ignited residuum of guano rarely affords even a trace of effervescence with 
 dilute hydrochloric acid. 
 
 The following analysis of guano surprised me not a little, being formally issued from 
 a most respectable establishment : — 
 
 "Apothecaries' Hall, August 24. 1844. 
 " Gentlemen, — I have submitted the sample of guano from Ichaboe, left with me, 
 to a careful chemical analysis and investigation, and beg to report that it is the best 
 in quality for agricultural purposes that has yet come under my notice ; besides the 
 annexed analysis, I find that it contains nitrogenous organic ingredients capable of 
 yielding 24 per cent, of ammonia : — 
 
 " Salts of organic acids, salts of ammonia, and organic acids, all 
 
 soluble in cold water - - - - - 33*0 
 
 Insoluble organic matter, acids, &c. - - - 9 '5 
 
 Phosphate of lime - - - - - - 30 O 
 
 Chloride of sodium, sulphate of soda, and phosphate - 1 '0 
 
 Water of crystallisation and moisture - - - -25*0 
 
 Insoluble in acids (argillaceous) - - - - 1 *5 
 
 100-0 
 
 " By the term * organic acids ' I mean the uric acid, and acids of that class, rich in 
 nitrogen, and therefore capable of yielding a rich manure and vegetation. The per 
 centage of phosphate of lime is also higher than the average. 
 
 (Signed) " Robt. Warrington, Chem. Operator. 
 
 " Messrs. Miller and Potter, 
 Owners of the Joseph Hume, from Ichaboe." 
 
 This printed report — calculated to produce astonishment in the trade, to lead to a 
 rapid sale of the article at a high price, as exhibiting a guano rich beyond the boasted 
 treasures of Peru, and to excite ship-owners to send off a fresh fleet to the African El 
 Dorado — was given to me by a gentleman who dealt in that manure, and soon after a 
 sample of the said guano was sent to me for my professional analysis. 
 
 The results of a very careful chemical investigation, verified by repetition, were very 
 different indeed from that of the Apothecaries' Hall. I could find no uric acid in it, 
 nor any acid of that class rich in nitrogen, and no alumina. But instead of giving the 
 details of my own analysis, I shall present those of a professor of chemistry in London, 
 conversant with the analysis of organic matter, and particularly with the ultimate ana- 
 lysis for determining the "nitrogenous organic ingredients, capable of yielding 24 per 
 
APPENDIX II. 
 
 GUANO. 
 
 301 
 
 cent, of ammonia," according to Mr. Warrington. That gentleman's analysis of the 
 guano per Joseph Hume is as follows : — 
 
 " 50 grains of guano in the moist state, decomposed with an equal weight of car- 
 bonate of potash, gave 4*13 grains of ammonia, or 3 -4 grains of nitrogen. 
 25 grains of guano, carefully dried at 212°, were then mixed with hydrate of soda 
 and quicklime, and ignited. They produced 2-17 grains of nitrogen. 
 Hence we have, in 100 parts of guano in the moist state, — 
 
 Nitrogen, in the condition of (actual) ammonia - 6-80 
 Ditto (in the potential state) - - - - 2*64 
 
 Total quantity of nitrogen - - 9"44 
 
 The (actual) ammonia I believe to be chiefly in the state of oxalate." 
 
 Since 14 of nitrogen are equivalent to 17 of ammonia, 
 
 9*44 are equivalent to 11 *46 instead of 24 ! 
 — a result very different indeed from that of the Apothecaries' Hall chemistry. — Is 
 argillaceous matter insoluble in acids at the Hall ? 
 
 My own analysis made as to the ammonia, in presence of a most respectable chemist, 
 but not of the professor above referred to, agrees very closely with the preceding. The 
 guano was a good African cargo, fully equal in value to the average of that from Icha- 
 boe, and did not stand in need of puffing to make it fetch a fair price in the market. 
 Indeed, such an extravagant character as Mr. Warrington gave it, was more likely to 
 raise suspicions, than to give satisfaction to dealers. 
 
 The Apothecaries' Hall analysis gives 30 of phosphate of lime; 1 of chloride of 
 sodium, sulphate of soda, and phosphate ; 25 of water ; and 1± of insoluble in acids 
 (argillaceous); in all 51\, leaving 42| for the other constituents in 100 parts. Now, 
 as Mr. Warrington is also secretary to the Chemical Society of London, he should 
 offer to its president, and the members, the following problem for a prize essay : 
 Given 33 parts of salts of organic acids, salts of ammonia, and organic acids, all soluble 
 in water, with 9\ parts of insoluble organic matter, acids, $*c, to extract from these 42| 
 parts, 24 parts of ammonia. The chemist of the London school who shall achieve 
 this feat, will throw Berzelius, Faraday, Liebig, and Dumas into the shade. 
 
 It has been objected, I am told, to my method of determining the potential ammonia 
 of guano — viz., the ammonia equivalent to the azotised organic matter — that the 
 process of igniting it in mixture with hydrate of soda and quicklime is inapplicable, 
 because an unknown portion of ammonia must escape and be lost in the act of mixing 
 the guano with these decomposing agents ; but this objection will not be made by 
 any skilful experimentalist who pursues the steps pointed out by me — namely, to dry 
 the guano thoroughly beforehand by a steam heat, and to mix it finely pulverised with 
 the fine powder of the mixed soda and lime. I made this experiment in the presence 
 of Professor Redwood, upon a guano from Ichaboe, which contained nearly 8 per cent, 
 of actual ammonia, and no ammonia whatever was exhaled during the complete but 
 gentle trituration of the ingredients together in a porcelain mortar. At my request, 
 Mr. Fownes, lecturer on chemistry at the Middlesex Hospital, who studied at the Uni- 
 versity of Giessen, made the same experiment, and he writes me, — "I have great 
 pleasure in confirming your observation, that the carefully-dried guano may be cau- 
 tiously mixed with the alkali in Wills' process, without loss of ammonia, by a little 
 management. " 
 
 In fact, the ammonia is so enveloped in the organic matter and phosphate of lime of 
 guano, that when freed from moisture, no ammonia is separated during the short period 
 requisite for mixing its powder intimately with the dry powder of lime and soda. 
 
 The following Report of Professor Johnston upon his analysis of a sample of 
 guano, imported in the Maid of Alicant, was recently sent to me by eminent guano 
 merchants in London for my opinion upon his mode of estimating the relative value 
 of that article merely from the proportion of water it may contain. As this analysis, 
 like his other one given above, does not exhibit the quantity of ammonia, either actual 
 or potential, in the guano, it is therefore, in a chemical point of view, as worthless 
 as an assay of a silver, copper, or tin ore would be, which did not state the precise 
 amount of metal present in it. 
 
 (COPY.) 
 
 "8. Bank Street, Edinburgh, March 10. 1845. 
 " Gentlemen, — At the request of Mr. Souter, of Banff, I enclose a copy of the 
 analysis of a sample of guano, from the Maid of Alicant, sent to me for examination by 
 that gentleman, and of the opinion I have given him in reference to its value. 
 
 " I have the honour to be, yours truly, J. F. Johnston. 
 
302 
 
 GUANO. 
 
 APPENDIX II. 
 
 " It is a good Ichaboe guano, of fair average quality in every other respect but that ' 
 of the quantity of water it contains. In this respect it is about 4 per cent, below 
 the average of the numerous varieties of guano examined in my laboratory. I consider 
 about 23 per cent, of water to be about the average ; so that you are entitled, if what I 
 received be an average of the cargo, to a deduction of 4 per cent, by the terms of your 
 agreement." 
 
 Here follows his 
 
 " Analysis of Guano, ex Maid of AUcant. 
 
 "Water - - - - - - 27 39 
 
 Organic matter and ammoniacal salts - 40*04 
 
 Common salt, sulphate and phosphate of soda and potash - 7 '51 
 
 Phosphate of lime and magnesia - - - - 23 '63 
 
 Carbonate of lime ------ 0*21 
 
 Insoluble siliceous matter - - - - - 0*97 
 
 Loss ------- o-25 
 
 100-00" 
 
 My extensive experience in the analysis of guano during nearly four years leads me 
 to regard this rule of the Professor as entirely fallacious. The proportion of water 
 present in Ichaboe guano depends very much upon the proportion of animal organic 
 matter which it contains. When this is wasted by the atmospheric elements, when it 
 has undergone the eremacausis of Liebig, and has degenerated into a carbonaceous caput 
 mortuum, it is less retentive of moisture, and also of less weight relatively to the 
 unchangeable silica, phosphate of lime, and magnesia. 
 
 In last October an Ichaboe guano, analyzed by me for an eminent merchant in the city 
 of London, which contained only 23 per cent, of water, appeared doughy from moisture ; 
 an appearance caused by the almost total absence of animal organic matter, and the great 
 proportion of phosphate of lime. It contained only 1 *85 per cent, of actual ammonia, 
 no uric acid or other azotized matter capable of yielding ammonia by slow decomposition 
 in the soil. Now, the guano ex the Joseph Hume, as quoted above, though it con- 
 tained 2 per cent, more water, was not doughy, but pulverulent. By Mr. Johnston's 
 rule this guano was 2 per cent, worse than the preceding, and yet it was intrinsically 
 50 per cent, at least better, because it contained nearly 7 times more ammonia, a 
 double quantity of animal organic matter, and that in a fresh state, along with 30 per 
 cent, of phosphate of lime. In fact, a decomposed guano, with 23 per cent, of water, 
 and so little ammonia as the above, is worth little more than the value of the bone 
 earth in it. 
 
 I have this day (17th March, 1845) despatched the report of my analysis of an Ichaboe 
 guano to a gentleman in Leominster. Though a dry- looking powder, it contains no 
 less than 29 per cent, of water, and is notwithstanding an excellent article, being the 
 pure and little-wasted excrement of sea-birds. These statements clearly prove that 
 the proportion of water constitutes no sure criterion of the value of guano, but that 
 this is to be deduced from a collation of all its useful constituents, most especially the 
 exact proportion of its ammonia, actual and potential, which Mr. Johnston's analyses 
 do not not state, next of its alkaline salts, particularly those of potash, then of its phos- 
 phate of lime and magnesia, and of its uric acid. I here subjoin the reports of the 
 analyses of two different samples of guano for my Leominster correspondent. 
 "1. C. sample. Ichaboe. 
 
 " Specific gravity, 1*3 to water 1*0; being the lowest density of any guano which has 
 hitherto passed through my hands, and indicating it to be pure bird excrement. 
 100 parts consist of — 
 
 " 1. Animal organic matter, partially decomposed, affording 7*82 per cent, of 
 
 actual ammonia, and 1 *02 of potential ammonia; in all, 8*84 of ammonia 37 '3 
 2. Fixed alkaline salts, of which about the one-half is valuable potash salts, 
 
 the other sulphate and muriate of soda - - - 4*7 
 
 3. Phosphate of lime, with a little phosphate of magnesia - - 28-0 
 
 4. Siliceous sand - - - - ' - - -1*0 
 
 5. Moisture separable at the heat of 212° Fahr. - 29 0 
 
 " It contains hardly a trace of uric acid. 100 0 
 
 " 2. Sample P. Peruvian. 
 " Specific gravity 1 -4 ; being a low density for so dry a guano. 
 "100 parts consist of — 
 
APPENDIX II. 
 
 MANGANESE. 
 
 303 
 
 " !. Animal organic matter, in a fresh state, affording 3*74 of actual, and no 
 less than 12*92 of potential ammonia; in all 16*66 of ammonia, along 
 with 9 of uric acid - - - - - . -60*5 
 
 2. Fixed alkaline salts, about two-thirds of which are potash salts, so valuable 
 
 for corn crops, and about one-third sulphate and muriate of soda - 2*5 
 
 3. Phosphate of lime, with a little phosphate of magnesia - 23*0 
 
 4. Siliceous fine sand (drifted into the guano) - - - - 6*0 
 
 5. Moisture separable at a heat of 212° Fahr. - - - - 8*0 
 
 100-0" 
 
 From its large proportion of rich organic matter, uric acid, and potential ammonia, 
 this guano will communicate fertility to the soil for several years ; whereas the sample 
 C. is to be regarded as a quicker manner for one season. Both will act perennially 
 by their bone phosphate. Andrew Ure, M. D. F. R. S., &c. 
 
 HAIR DYE. The compound of lime and litharge, prescribed in the Dictionary 
 for dyeing hair, should be used with great caution, as, when applied in a too-little diluted 
 state, it is apt to destroy the hair. A much better and a perfectly safe hair dye pre- 
 sents itself in pyrogallic acid, which may be prepared for this purpose by exposing 
 powdered nutgalls to heat in a hemispherical glass or porcelain vessel, covered with 
 tissue or filtering paper pasted round its edges, and surmounted with a bell glass. The 
 pyrogallic acid rises in vapour, which, being filtered from its oily impurities through 
 the paper, condenses on the inside of the bell glass. The pyrogallic acid thus obtained 
 is to be dissolved in water, purified by digesting the solution with animal charcoal, 
 then concentrated, and mixed with some alcohol to prevent its decomposition. This 
 tincture applied to the hair, browns it ; but it must not be allowed to touch the hands, 
 as its stain cannot be easily effaced. 
 
 MANGANESE. The recovery of this metal in the state of peroxide from the 
 several waste products of the chemical arts, in which it is so extensively consumed, has 
 been long a desideratum in manufactures. This important problem has at length 
 been happily solved by Mr. S. de Sussex, of the Millwall chemical works, near 
 London ; and in doing so, he has conferred a precious boon on the chemical world, 
 which I hope will be honestly and thankfully repaid by the sale of licenses under his 
 patent, specified only a few days ago. I have great pleasure in enriching the second 
 edition of my Supplement with an authentic description of the valuable series of 
 processes embodied in his plans. 
 
 The nature of the said invention is to regenerate or reproduce peroxide of manganese, 
 more or less pure, from salts and other combinations of that metal which contain it in a 
 lower state of oxidation. By this invention we can reconvert the residuum that is left 
 after the disengagement of chlorine or oxygen from manganese, and which is a product 
 of little or no value, into a substance of great value, namely, that superoxide of man- 
 ganese, which is peculiarly fitted, by the large proportion of oxygen it contains, to serve 
 the purpose of affording either chlorine or oxygen gas again, according to the process it 
 is subsequently subjected to. The said residuary matters, after the extrication of the 
 chlorine in the manufacture of chloride of lime, or bleaching powder, and of chlorate or 
 hyperoxymuriate of potash, consist principally of chloride and sulphate of manganese; 
 but as these residuums may and have been occasionally converted more or less into 
 sulphuret of manganese when they are used to purify coal gas from its sulphur or sul- 
 phuretted hydrogen, the patentee includes not only the above sulphate and chloride, 
 but also the sulphuret of manganese, among the waste or refuse products, which he 
 converts into a valuable peroxide of that metal. He applies, moreover, this invention 
 to the conversion of all oxides, carbonates, and other combinations of manganese what- 
 ever, whether native or factitious, which contain the metal in an inferior state of 
 oxidation, into a superoxide of manganese, adapted to produce chlorine by the agency of 
 hydrochloric acid, and oxygen by the agency either of heat alone, or of heat along with 
 sulphuric acid. 
 
 The manner in which the said invention is to be carried into execution is as follows : 
 — The conversion of manganese, whether combined or uncombined from a lower 
 state of oxidation into the higher state of superoxide, is effected by two distinct 
 operations. First, it is well known that when peroxide of manganese, called in its 
 purest native state, pyrolusite, and also grey manganese ore, is digested with hydro- 
 chloric or muriatic acid, the oxygen of the metal combines with the hydrogen of the 
 acid to form water, and leaves the chlorine of the acid free, while the manganese, thus 
 partially stripped of its oxygen, combines with the rest of the hydrochloric acid to form 
 a muriate of manganese. Likewise, when more or less dilute sulphuric acid, common 
 salt (chloride of sodium), and peroxide of manganese, are so mixed and treated as to be 
 
304 
 
 MANGANESE. 
 
 APPENDIX II. 
 
 made to re -act on one another, the hydrochloric acid, which is disengaged, is con- 
 verted by the oxygen of the manganese into water and chlorine, while both the soda 
 produced from the common salt, and the partially deoxidised manganese, combine with 
 the sulphuric acid into sulphate of soda and sulphate of manganese. He converts 
 either the chloride, sulphate, sulphuret, or carbonate, into a sesquioxide or deutoxide 
 of manganese, by one or other of the three following processes : — First, he subjects 
 dried chloride of manganese to a strong heat, produced either by the united action of 
 burning fuel, and a jet or jets of an oxy-hydrogen blowpipe, or of a stream of 
 atmospheric air thrown upon the burning fuel by a fan or other suitable impulsive 
 power, thus forming a kind of blowpipe or blast-furnace, in which the chemical decom- 
 position and re-action are rendered quicker and more complete. The furnace is con- 
 structed like an ordinary reverberatory furnace, with the addition of a box or chest of 
 iron open at top, set in the fire-place, close to the bridge, which box is filled with iron 
 turnings, borings, or other small fragments of iron, upon which, in their strongly ignited 
 state, water is allowed to trickle or drop down slowly from a pipe, so as to be decom- 
 posed, and to disengage a stream of hydrogen, which is impelled over the bridge of the 
 furnace upon the hearth by means of a fan or other blowing machine acting at the entrance 
 or door of the fire-place. The manner in which the furnace is regulated is as follows:—. 
 The fuel, either common coals, coke, anthracite, wood, turf, &c. is first lighted upon 
 the grate, and being subjected to the blast of air, soon creates such a temperature as to 
 raise the box of iron turnings to a red-white heat, in which state the water being 
 allowed to trickle down into the said box, is decomposed with the copious disen- 
 gagement of hydrogen gas. The chloride of manganese may be exposed on the hearth 
 of the reverberatory furnace either in a more or less concentrated liquid state, or in a 
 dry state, to the action of the intensely powerful flame, generated as above described, 
 and becomes thereby decomposed by the hydrogen, with the disengagement of its 
 chlorine in the state of hydrochloric acid or muriatic acid gas, while the remaining 
 protoxide of manganese becomes at the same time oxidized into the deutoxide. The 
 hydrochloric acid gas disengaged is condensed by means of vaults or large chimneys, 
 containing wet coke or flint nodules in the way often practised in soda manufactories. 
 Instead of the above described hydrogen flame, he employs sometimes a simple rever- 
 beratory furnace with ordinary fuel, either with or without blast, in which he resolves 
 the chloride of manganese into hydrochloric acid and peroxide of manganese, but he 
 prefers the compound flame of hydrogen and ordinary fuel. 
 
 In his second process, instead of acting on chloride of manganese by the flame of 
 combustible matter on the hearth of a furnace, he subjects the chloride of manganese, 
 put into fire clay retorts, to an intense heat, by which he expels the chlorine partly in 
 the state of hydrochloric acid, and partly of chlorine, and the manganese left in the 
 retorts may be afterwards peroxidized by a process to be presently described. 
 
 In his third process he mixes together chloride of manganese and carbonate of lime, 
 or quicklime, in the proper equivalent proportions for mutual decomposition, and he 
 subjects that mixture to the strong heat of the above described compound hydrogen 
 flame, whereby he obtains a mixture of chloride of calcium (muriate of lime), and oxide 
 of manganese, which he peroxidizes by a process about to be described. Magnesia, or 
 magnesian limestone, may be substituted for lime, or its carbonate, in this process. 
 When the carbonate of lime is used, with rather too low a heat in the furnace, car- 
 bonate of manganese may be formed. In all cases, the resulting mixture of chloride of 
 calcium or magnesium, and oxide of manganese, is, to be treated with water, so as to 
 dissolve out the said chlorides, and leave the oxide of manganese. 
 
 The following is his plan of decomposing sulphate of manganese, however formed, 
 so as to obtain from it an oxide of manganese, to be peroxidized by an after pro- 
 cess : — 
 
 He mixes the sulphate of manganese with saw-dust, ground coke or charcoal, or any 
 like combustible matter, only in such proportion as to be capable of decomposing the 
 sulphuric acid present, when the mixture is subjected to a strong calcining heat in 
 retorts of iron, or preferably of fire-clay, whereby he obtains a sulphuret of manganese, 
 mixed with more or less oxide of manganese. He finishes this operation, by intro- 
 ducing into the said residuary mixture, fragments of coke, charcoal or coal, and con- 
 tinuing the application of heat for some time, while the mouth of the retort is left 
 open, whereby he desulphurates the manganese in a greater or less degree, and converts 
 its sulphuret into an oxide. In case any salt, or other compound of soda, should have 
 been mixed with the sulphate of manganese, the soda compound is to be separated from 
 the manganese by means of water, after the above described calcination in the retorts. 
 The sulphuret of manganese sometimes produced in coal gas works, as a residuum of 
 the purification of the gas, may be desulphurated in retorts as above described, or pre- 
 ferably by exposing it mixed with pieces of coke, charcoal, coal or wood, on the hearth 
 of the above described reverberatory hydrogen furnace. The coke, &c. should be used 
 
appendix n. SILVERING OF GLASS. 
 
 305 
 
 not in powder, but in distinct pieces, whereby it may be readily separated from the 
 oxide of manganese afterwards, either by a sieve or other suitable means. 
 
 The following is his manner of performing the second operation, or series of opera- 
 tions, whereby he converts the deutoxide of manganese produced in the before- 
 described processes, as also all lower oxides and the carbonated oxide of manganese, 
 whether natural or factitious, into a superoxide lit for affording chlorine by the action 
 of hydrochloric acid, and oxygen by heat ; and he produces the said peroxidizement in 
 one or other of the three following ways. First, he converts the said oxides or car- 
 bonates from their lower to the much higher state of oxidation of an acid of man- 
 ganese, by subjecting a mixture of them with alkaline matters, such as potash or soda, 
 either caustic or carbonated, on the hearth of a reverberatory furnace, to the joint 
 agency of heat and atmospherical oxygen, which may or may not be impelled and dif- 
 fused by mechanical means. He finds that about one part of the oxide or carbonate of 
 manganese, mixed with about three parts of alkaline matter, forms a suitable propor- 
 tion for the production of an acid of manganese. The said mixture fuses with the 
 production of a manganate or permanganate of potash or soda, according as one or other 
 alkali has been used in the mixture. The fused, mass is run or laded out of the fur- 
 nace, and when cooled is dissolved in hot water. This solution, of what is sometimes 
 called chameleon mineral, on being exposed freely to the air, becomes decomposed, by 
 the absorption of carbonic acid gas, into peroxide of manganese, which precipitates in 
 a black powder, and carbonated alkali which remains in solution. Where carbonic 
 acid gas can be conveniently procured at a very cheap rate, the above described decom- 
 position of the chameleon mineral may be promoted by a due application of the said 
 acid gas. Or, otherwise, the alkaline bicarbonates obtained from a preceding decom- 
 position of chameleon mineral, may be employed for decomposing a fresh-made 
 solution of the said chameleon, whereby a precipitate of peroxide of manganese is 
 immediately obtained. The supernatant alkaline liquor is in all cases decanted or run 
 off, and reserved for subsequent use. He also decomposes chameleon mineral with 
 the production of peroxide of manganese by the action of various organic products, 
 such as starchy or gummy matters, but he greatly prefers to effect the desired pro- 
 duction of peroxide of manganese by carbonic acid gas, or an alkaline bicarbonate. 
 His second method of producing peroxide of manganese from its lower oxide or car- 
 bonate, consists in subjecting a mixture of about one equivalent chemical proportion of 
 either of these, and about one equivalent of lime, to the chlorine expelled by heat from 
 chloride of manganese contained in the retort, as heretofore described. Or, by treating 
 one equivalent proportion of that lower oxide of manganese, called by chemists sesqui- 
 oxide or deutoxide, with one half of an equivalent proportion of aqueous or liquid 
 hydrochloric acid, he obtains simultaneously one half of an equivalent proportion of 
 protochloride of manganese in solution, and one half an equivalent of peroxide in the 
 state of a black powder. A like re-action, with the production of a solution of proto- 
 chloride of manganese, and black peroxide, may be effected by treating the said sesqui- 
 oxide with aqueous hydrochloric acid in one vessel, and transmitting therefrom the 
 chlorine disengaged into another vessel, containing a like sesquioxide in a moist state. 
 
 His third method of converting into peroxide of manganese, its lower oxide or car- 
 bonate, consists in directing over the surface of either of these, in a moist state, the 
 deutoxide of azote, frequently called nitrous gas, which is obtained as a waste product 
 in certain chemical operations, as in the manufacture of oxalic acid, or nitrate of lead, 
 or of copper, &c. 
 
 In this case, the nitrous gas becomes reduced to a lower state of oxidation, and by 
 imparting oxygen to the lower oxide of manganese, converts it into peroxide 
 
 MANURE MANUFACTURE. The fcecal matter so abundantly collected and 
 dried in Paris, to form their dry portable manure, called poudrette, is now mixed in its 
 preparation with a small portion of a solution of sulphate of iron (copperas), whereby it 
 loses its offensive smell, and may be evaporated without causing a nuisance to the 
 neighbourhood. The ammonia, as well as the sulphuretted and phosphuretted 
 hydrogen, which together concur to produce the nauseous effluvia, are at once con- 
 densed by this salt ; the ammonia by its acid, and the gases by its oxide. When the 
 putrid contents of a cesspool are mixed with a little copperas, they soon become nearly 
 inodorous. This cheap metallic compound should be applied, under the administration 
 of the police, to all the masses of putrefying dung which are deposited in the purlieus 
 of London, and of the other large towns in the United Kingdom. 
 
 OXALIC ACID. By exposing 100 parts by weight of dry sugar to the action 
 of 825 parts of hot nitric acid of 1 *38 specific gravity, evaporating the solution down 
 to one-sixth of its bulk, and setting it aside to crystallize, from 58 to 60 parts of 
 beautiful crystals of oxalic acid may be obtained, according to Schlesinger. 
 
 SILVERING OF GLASS. A coating of silver, not of tin amalgam as on common 
 mirrors, is deposited on gla,ss by the following process of Mr. Drayton. The plate being 
 
 R r 
 
306 
 
 SOILS, ANALYSIS OF. 
 
 APPENDIX II. 
 
 Fig. 192. 
 
 surrounded with a raised border of glazier's putty, is then covered with a solution of 
 nitrate of silver, with which a little alcohol, water of ammonia, as also oils of cassia and 
 cloves, have been mixed. The silver is precipitated by the re-action of the alcohol and 
 oils in a metallic state. This method will serve to silver small irregular and polygonal 
 surfaces of glass very conveniently ; but the cost of the precious metal } &c. will preclude 
 its application to large mirrors. 
 
 SOILS, ANALYSIS OF. Having been recently engaged in a minute chemical 
 examination of the soil of a large farm, remarkable for perennial fertility without 
 manure*, I have been led to adopt some simplified methods of analysis, which may to a 
 certain extent be practised by ordinary farmers, and may throw some light on the 
 means of improving permanently the composition of their lands. The field from which 
 the sample subject of analysis was taken, is situated on Marsh Farm, in Haveling Level, 
 in the parish of Hornchurch, Essex, not far from the banks of the Thames, and 
 nearly opposite to Erith. R. M. Kerrison, Esq., M.D. F. R. S., the proprietor, informs 
 me that no manure has ever been applied to this farm of 200 acres during a period 
 of at least fifty years, except once ; and in that season the wheat became so heavy 
 as to be in a great measure spoiled. It produces every variety of crop most 
 abundantly. 
 
 The substratum, which lies beneath a three-feet bed of the soil, is an alluvial deposit, 
 replete with decaying vegetable matter ; the remains probably of some ancient forest, 
 which existed prior to the formation of the Daggenham Breach, through which the 
 river had inundated a large district of country, and kept it submersed till about two 
 
 centuries ago ; when it was stopped out by the 
 Cy, aid of a Parliamentary grant, administered under 
 
 the direction of a skilful engineer. The soil 
 over the whole farm is of very uniform texture 
 and appearance ; being a finely comminuted 
 friable loam, quite free from stones, consisting 
 of a fortunate mixture of fine siliceous sand, 
 clay, oxide of iron, and carbonate of lime, with 
 minute proportions of phosphate of lime and 
 magnesia, but very little organic matter. It 
 would seem, therefore, to derive its principles 
 of fertility chiefly from the atmosphere, and the 
 emanations from the subsoil. 
 
 The specific gravity of the soil, in its average 
 state of dryness, is 2 -2 to water called 1 *0 ; in- 
 dicating the presence of but little vegetable 
 matter. 
 
 100 parts of it collected after a period of or- 
 dinary dry weather lose 1 1 '2 by a steam heat 
 of 212°, and readily re-absorb that portion of 
 moisture when again exposed to damp air. 
 When the dried residuum is calcined at a dull 
 red heat, six parts of vegetable substance are 
 burned away ; at a higher temperature the car- 
 bonate of lime woujd become calcined, and 
 cause an additional loss of weight, which might 
 inconsiderately be mistaken for organic matter. 
 
 The first problem in an agricultural analysis, 
 is to find the proportion of calcareous matter, 
 as carbonate and phosphate of lime. This may 
 be easily solved with the aid of the following 
 instrument {fig. 192.), which may be called 
 the Limestone Meter, one of which was presented 
 and explained by me to the Council of the Royal 
 Society of Agriculture on the 29th of May last. 
 
 A, is a cylinder of glass, two inches in di- 
 ameter, and fourteen inches long, graduated on 
 one side with a scale, into spaces of 100 water- 
 grain measures from 0 to 12,000, marked 10, 
 20, 30, &c; and graduated on the other side 
 into spaces of 240 water-grain measures, each. 
 The former scale is used for the analysis of all 
 Jyk, sorts of alkaline carbonates, and also of acids ; 
 
 
 
 
 
 
 -0 
 
 in. 
 
 
 
 20- 
 30- 
 
 
 10 1 
 
 40- 
 
 50- 
 
 
 -20 
 
 60- 
 
 
 B 
 
 70- 
 
 
 30 
 
 80- 
 
 
 
 90- 
 
 
 -40 
 
 100- 
 
 
 
 110. 
 
 
 E § 
 
 120 i 
 
 
 "so (p§ 
 
 
 
 * All the stable-yard dung is sold by the farmer, 
 
appendix ii. SOILS, ANALYSIS OF. 
 
 307 
 
 the latter is adapted to the direct analysis of carbonate of lime and marls ; and indi- 
 rectly to that of phosphate of lime and carbonate of magnesia. 
 
 The cylinder A, has a tubulure in its side near to the bottom ; this is closed with a 
 cork, in the axis of which a short glass tube is cemented, hooped externally to a collar 
 of caoutchouc E, which serves as a joint to the upright long glass tube B, held near its 
 upper recurved end in a hooked wire. 
 
 The top of the cylinder A is closed with an elastic cork, through a perforation in 
 which the taper tail of the little phial C passes air-tight. The small tube F, open at 
 both its ends, is cemented on its outer surface, into the bottom of the phial C, so as to 
 close it, while the tube itself opens a free passage to gas, from the shoulder of the phial 
 down into the cylinder A. 
 
 The mouth of the phial C is shut with a cork, through which the small end of the 
 tube D passes air-tight. The tube D is graduated into spaces of 10, 20, &c. water- 
 grain measures up to 250, and is closed at top with a stop-cock. Its lower and 
 capillary extremity is recurved. 
 
 In ascertaining with this instrument the proportion of real carbonate of lime, in any 
 limestone, marl, or soil, proceed as follows : — 
 
 Lift out the phial C, and pour water into the cylinder A till it stands about half an 
 inch below the line marked 0, and fill up this space with common linseed-oil. Restore 
 the phial C to its place, pressing it in air-tight. Then take out its cork with its 
 graduated tube, and introduce into the phial as many grains weight of the soil or marl 
 as it is proper to operate upon. Of an average limestone 50 grains are sufficient, 
 because the magnified scale of the lime-proof is adapted to the analysis of 50 grains of 
 pure carbonate of lime. Of soils and marls, 100, 200, or even 500 grains, may be 
 taken, because these substances will rarely contain one-tenth their weight of carbonate 
 of lime. But as the result may always be obtained within five minutes, at the cost of 
 half a farthing, several successive experiments may be made on different weights of the 
 sample. Having introduced the proper weight of the object into the phial, cover it 
 with water, till this stands a little above the point to which the recurved tube descends. 
 Holding D in the hand, dip its bent point into a phial containing ordinary muriatic 
 (hydrochloric) acid, diluted with its own bulk of water, and applying the mouth to 
 the opened stop-cock, suck up the acid into the tube till this be about two-thirds full, 
 then turn the key of the cock before it is taken from the lips, and the acid will not 
 drop out when the tube is held upright. Replace the cork with its tube D in the 
 phial C. Detach the long tube, B, from its wire-rest with the left hand, and hold its 
 curved extremity above an empty basin ; then with the right hand open the stop-cock 
 of D, to let a little acid run down upon the marl, but shut it almost instantly again, 
 lest too much acid should escape, and cause so brisk an effervescence as to occasion an 
 overflow of the mixture into the small tube F. The disengaged carbonic acid escapes 
 through the tube F, presses on the surface of the oil in A, and causes a stream of water 
 to flow from the tube B, into the subjacent basin. When the water ceases to run, open 
 the stop-cock again, when more acid will descend, cause a fresh extrication of gas, and 
 a further flow of water. The curved end of the tube B should be progressively lowered, 
 as the oil falls in A, so as to maintain its level and that in the tube, in the same hori- 
 zontal plane. Whenever gas ceases to be extricated by the muriatic acid, the experiment 
 is completed, and the number on the lime-meter scale opposite to the upper surface of 
 the oil, denotes the number of grains of carbonate of lime, in the quantity of limestone, 
 marl, or soil, put into the phial C for experiment. A little carbonic acid gas remains 
 condensed in the muriatic solution, but this is not more than equivalent to the bulk of 
 liquid acid introduced into the capacity of the apparatus ; so that no compensation need 
 be made in this account. For the purpose of minute chemical research, that portion 
 of gas may be expelled by surrounding the phial C with a cloth wrung out of hot water, 
 and the volume of dilute acid added, may also be taken into the account. Thus the 
 composition of carbonates by an acid, and of acids by a bi-carbonate, may be determined 
 by means of this instrument with equal rapidity and precision. 
 
 The contents of the phial may be poured out into a porcelain capsule, gently heated, 
 and thrown on a filter. The lime of the carbonate, as well as the phosphate of lime and 
 the magnesia, will pass through in solution along with a very little iron. On super- 
 saturating the acidulous liquor with water of pure ammonia, phosphate of lime (if 
 present) will fall, and may be drained on a filter and dried. Taken off the dried filter, 
 and digested with a little dilute sulphuric acid, sulphate of lime will result, character- 
 ised by its entire insolubility in dilute alcohol. Hence the sulphate washed with 
 vinous spirits, dried and calcined, will represent by its weight one-fifth more than the 
 original weight of the phosphate. By the action of the sulphuric acid, the iron pre- 
 cipitated by the ammonia with the phosphate is got rid of. 
 
 The magnesia, unless its proportion has been very great, will all remain dissolved as 
 ammonia-muriate, and its quantity may be ascertained by precipitating it either with 
 
 R r 2 
 
308 
 
 SOILS, ANALYSIS OF. 
 
 APPENDIX II. 
 
 soda, or phosphate of soda. In the former case, the substance obtained when washed 
 on a filter, dried and ignited, is pure magnesia; in the latter, it is the ammonia- 
 phosphate of magnesia ; and when dried at the moderate heat of 120° Fahr., it represents 
 by its weight about six times that of the magnesia present ; or for 100 parts, 16^ of 
 magnesia. 
 
 When a complete analysis of a soil is to be made, the following apparatus is con- 
 venient : — 
 
 A large glass flask, or matrass, with a sucked-in or concave thin bottom. This should 
 hold at least a quart of water j and when the soil and dilute acid are introduced, it is to 
 be placed an a stand over the gentle flame of a spirit lamp, while the beak of a large 
 glass funnel, having its mouth covered with a porcelain basin, filled with cold water, is 
 inserted into the neck of the flask. By this arrangement a continual ebullition may be 
 maintained in the mixture of soil and acid, without loss of acid, or nuisance from its 
 fumes, because the vapours are condensed whenever they reach the cold basin above 
 the funnel, and a perpetual cohobation takes place. A boiling heat may be kept up in 
 this way till every constituent of the soil, except the silica, becomes dissolved. Mu- 
 riatic acid is generally preferred for the analysis of soils, and in somewhat greater 
 quantity than the bases in the given weight of soil can neutralise. The funnel and 
 porcelain basin should be properly supported upon the rings of a chemical stand. 
 I generally subject 100 grains of soil to the action of boiling dilute acid in this way 
 for 6 or 8 hours ; at the end of that period I throw the contents of the matrass upon 
 a filter, and supersaturate the filtered liquid with ammonia, The silica which 
 remains on the filter having been washed in the process, is dried, ignited, and 
 weighed. 
 
 The alumina, iron-oxide, and phosphate of lime, thrown down by the ammonia, 
 being washed in the filter, and dried to a cheesy consistence, are removed with a bone 
 or tortoise- shell blade into a silver basin, and digested with heat in a solution of pure 
 potash, whereby the alumina is dissolved, when its alkaline solution is to be passed 
 through a filter, then saturated with muriatic acid, and next supersaturated with 
 ammonia. Pure white alumina falls, which is to be separated on a filter, washed, dried, 
 ignited, and weighed. 
 
 The iron and phosphate of lime on the alkaline filter may be dried, gently ignited, 
 and weighed, or otherwise directly separated from each other without that step, by the 
 action of dilute alcohol, acidulated with sulphuric acid, at a gentle heat. Thus the 
 iron oxide will be dissolved, and its solution may be passed through a filter, while the 
 sulphate of lime will remain upon it, to be dried, ignited, and weighed. Five parts of 
 it correspond to four of phosphate. The iron is obtained by precipitation with water 
 of ammonia, filtration, and ignition. — For phosphoric acid, see the sequel. 
 
 The first filtered liquor, with excess of ammonia, contains the lime of the car- 
 bonate, and the magnesia. The former is separated by a solution of oxalate of am- 
 monia, with digestion in a moderate warmth for a few hours, filtration, and very gentle 
 ignition of the washed dry powder, when the pure carbonate of lime is obtained. The 
 magnesia, existing in the filtered liquor as an ammonia-muriate, may be obtained by 
 precipitation with soda, or phosphate of soda, as already described. 
 
 For some refractory soils, in which the alumina exists as a double or triple silicate, 
 it becomes necessary to fuse 50 grains of the sample, in fine powder, mixed with four 
 times its weight of dry carbonate of soda, the mixture being put into a platinum cru- 
 cible, and into a cavity in its centre, 50 grains of hydrate of potash being laid. 
 
 The crucible being slowly raised to a red-white heat, affords a fused liquid quite 
 homogeneous, of a grey or brown colour, according to the metals present in it. Man- 
 ganese gives a purple tint ; and iron a reddish brown. The fused matter should be 
 poured out into a shallow platinum basin ; and, whenever it cools, it should be pul- 
 verised, dissolved in dilute muriatic acid, the solution evaporated to dryness, the dry 
 mass again digested in hot water, acidulated with muriatic acid, and the whole thrown 
 upon a filter. Pure silica will remain on the filter, to be washed, dried, ignited, and 
 weighed. 
 
 The filtered liquor contains the remaining constituents of the soil, and is to be 
 treated as already described. 
 
 Besides these systematic investigations, researches may be made for certain peculiar 
 substances, and especially the neutro-saline constituents. In this view 100 grains of 
 the soil may be triturated with 20 times their weight of distilled water, placed in a 
 beaker, till the clayey matter subsides, and the clear portion may then be decanted into 
 a filter. A little of the filtered liquor should be tested with nitrate of barytes, and also 
 with oxalate of ammonia ; and if each portion yields a precipitate, they show the pre- 
 sence of sulphate of lime ; and the following steps ought to be taken to eliminate it 
 entirely: 200 grains of the soil should be triturated with a quart of distilled water, 
 holding 50 grains of sal-ammoniac in solution. The mixture should be allowed to 
 
appendix n. SOILS, ANALYSIS OF, 
 
 309 
 
 clarify itself by subsidence, when the supernatant clear liquor is to be filtered, 
 and evaporated down to 2 ounce measures, and then mixed with that bulk of strong 
 whiskey (11 per cent, overproof). The whole sulphate of lime will be now separated 
 from the fluid, and after being drained on a filter, may be dried, ignited, and 
 weighed. 
 
 For determining the alkaline salts, the water filtered from the 100 grains of the 
 soil should be evaporated down to one-fifth of its bulk, and then treated — 1st, with 
 nitrate of barytes, for the sulphates ; 2d, with nitrate of silver for the muriates ; 3d, 
 with oxalate of ammonia, for the nitrate or muriate of lime (provided no sulphate of 
 lime is indicated by the first test) ; 4th, with litmus paper, for alkaline or acid reaction; 
 5th, with soda-chloride of platinum for potash salts, which are very valuable for the 
 growth of many plants. 
 
 The portion of soil tested for potash salts should, before being digested in water, be 
 gently calcined, to ensure the . expulsion of every particle of ammoniacal salt, otherwise 
 the precipitate afforded by soda-chloride of platinum would be fallacious. 
 
 Another peculiar research of great importance is that which determines the amount 
 of ammonia in a soil ; and which may exist either ready formed, or in its elements, 
 capable of affording a portion of the azotic food so indispensable to vigorous vegetation. 
 The actual ammonia is easily obtained by distilling the soil along with some milk of 
 lime. The distilled water will contain all the volatile alkali, which may be measured 
 by the number of drops of a standard dilute acid, which it will saturate. 
 
 The potential ammonia, slumbering, so to speak, in its embryo elements, may be 
 estimated by igniting 200 grains of the soil with its own weight of a mixture of hydrate 
 of soda and quicklime, as described in my memoir on " Guano," in this Supplement. 
 
 I have subjected the soil of Dr. Kerrison's farm to the various modes of research 
 above enumerated, and have obtained the following results: — 
 
 1. By the application of my limestone- meter I obtained carbonic acid gas, equivalent 
 to 9 grains of carbonate of lime. 
 
 2. By igniting 200 grains of the soil along with 200 grains of mixed quicklime and 
 hydrate of soda, in the appropriate apparatus, I obtained 0*34 grains of ammonia, or 
 0*17 per cent, of the weight of the soil. Hence, 600 grains of the soil contain the 
 azotic equivalent of one grain of ammonia. This remarkable fact reveals most plainly 
 one secret source of the uninterrupted production of rich crops of cereals and other 
 plants from it, without receiving any manure. How appropriate to such land is Vir- 
 gil's beautiful title of the subject of his " Georgics," justisnma tellus ! 
 
 3. By the process of cohobation for 8 hours, with dilute muriatic acid, as also by 
 the process of fusion with alkalis in a platinum crucible, and the subsequent treatment 
 above detailed, I obtained — 
 
 I. 
 
 Silica - - - - 
 
 56-0 
 
 2. 
 
 Alumina - - - 
 
 8-0 
 
 3. 
 
 Oxide of iron - 
 
 5'5 
 
 4. 
 
 Carbonate of lime 
 
 9*0 
 
 5. 
 
 Sub-phosphate of lime 
 
 0-4 
 
 6. 
 
 Magnesia (carbonate) 
 
 0-5 
 
 *i 
 
 Moisture separable by steam-heat 
 
 11-3 
 
 8. 
 
 Organic matter, chiefly vegetable mould 
 
 6-6 
 
 9. 
 
 Moisture separable at a red- heat 
 
 2-7 
 
 
 
 100-0 
 
 besides traces of muriate of soda, and muriate of lime (chlorides of sodium and 
 calcium). The iron exists mostly in the state of protoxide, a circumstance owing, 
 probably, to exhalations from the subsoil of sulphuretted, phosphuretted, and car- 
 buretted hydrogen. The fresh soil is of a grey colour, but becomes ochrey-red by 
 calcination. 
 
 100 grains of the said soil, dried at 212°, absorb 8 grains of moisture in 24 hours ; 
 while 100 grains of the comparatively sterile soil of Regent's Park, dried equally, 
 absorb only 5 grains : a difference due chiefly to the finer comminution of the former. 
 
 Since the phosphates are such precious ingredients towards fertilising soils, it is 
 desirable to possess a clear and simple test of their presence. For this purpose digest 
 the soil, for an hour or so, with a moderate heat, in dilute nitric acid, free from 
 muriatic (viz. which affords, when largely diluted, no precipitate, by the addition of 
 a solution of nitrate of silver.) Throw the mixture on a filter, and to the filtered 
 liquid add potash-water, cautiously, till the instant that a precipitate begins to appear; 
 then drop into it a weak solution of nitrate of silver. If any phosphoric salts be 
 present, a yellowish precipitate will immediately fall, which is rc-soluble in an excess 
 
310 
 
 SOILS, ANALYSIS OF. 
 
 APPENDIX II. 
 
 of nitric acid. Whatever is not thus dissolved is chloride of silver, and ought to be 
 separated by filtration. On adding then weak water of potash (not ammonia) cautiously 
 to the filtered liquid, the pure phosphate of silver will be obtained, without any alumina 
 or iron, provided the liquid be still acidulous in a slight degree. It ought to be re- 
 membered that chloride of silver falls in a white curdy form, quite different from that 
 of the phosphate of silver. The portion of soil used for this experiment should be 
 fresh, and not calcined, because the phosphates, when ignited, afford white precipitates 
 with salts of silver. The stronger the solution of the phosphoric saline compound is, 
 the more characteristic is the yellow precipitate with silver ; and then ammonia may 
 be used for effecting the partial saturation of the acid excess. Sulphate of magnesia 
 is an excellent re-agent for detecting phosphoric acid, and for separating it from the 
 above acid solution, when it is partially neutralised with ammonia ; for the magnesia 
 forms, with the phosphoric acid and ammonia, the insoluble granular precipitate of 
 ammonia-magnesian phosphate. A solution of sulphate of magnesia, containing a 
 little sal-ammoniac, is probably the best test-liquor for detecting phosphates in faintly 
 acidulous, but still better in neutral, solutions. 
 
 In almost all soils of an arable nature under cultivation in this country, there is a 
 sufficiency of calcareous matter present to counteract the'combination of phosphoric acid 
 with alumina or oxide of iron, for which reason it would be an idle refinement of agri- 
 cultural analysis to search for phosphates of alumina and iron. As for manganese, 
 often associated with iron, it exists in too small a proportion, and is possessed of too 
 little value, to make it worth while to effect its separation. It gives to calcined iron- 
 oxide a black hue, and is characterised in its saline solutions by the flesh-coloured pre- 
 cipitate which it affords with hydro-sulphuret of ammonia, after the whole of the iron 
 has been thrown down by boiling the solution of the two metals with pure carbonate 
 of lime. 
 
 The organic matter in any soil may be correctly estimated by calcining its powder 
 pretty strongly till the carbonic acid be expelled from the lime in it. The loss of 
 weight, deducting that due to the carbonic acid gas (which is known from an 
 independent experiment), gives the quantity of organic matter. Its quality is deter- 
 mined by the ultimate analysis by means of hydrate of soda and quicklime, as pre- 
 viously stated. 
 
 The phosphoric acid may be also estimated by digesting the ignited soil in nitric 
 acid, precipitating the filtered solution with acetate of lead in excess. If phosphoric 
 acid be present it will produce phosphate of lead, mixed with a sulphate, if any sul- 
 phuric acid existed in the soil. Wash, ignite, and weigh the precipitate. Digest in 
 nitric acid, decompose the solution with sulphuric acid, add alcohol, throw the 
 mixture upon a filter, and weigh the sulphate of lead remaining left upon it. From 
 this weight, that of the oxide of lead becomes known; since 152 of sulphate of lead 
 contain 112 of oxide. The quantity of sulphuric acid found by nitrate of barytes 
 in another equal portion of the soil, being added to the oxide of lead just determined, 
 will constitute a sum, which, being subtracted from the weight of the acetate of lead 
 precipitate, will represent the amount of phosphoric acid in the soil. 
 
 In the very elaborate analyses of the ashes of different kinds of wheat, by Fresenius 
 and Will in Germany, Bichon in Holland, Boussingault in France, and others, one 
 half of the whole was found to be phosphoric acid. 
 
 • In the preceding method of analysis the detection of potash is made directly by 
 means of the soda-chloride of platinum. The following process is adapted to deter- 
 mine the quantity of that important alkali, as well as of soda. The solution of the 
 soil in hydrochloric acid is to be treated with barytes water till the liquid blues 
 reddened litmus paper ; it is then heated and thrown upon a filter. By this means 
 the whole of the sulphuric and phosphoric acids, as also of the oxide of iron, the 
 magnesia and the lime that was combined with the phosphoric acid, is separated. 
 The precipitate is to be washed till the water which passes ceases to be affected 
 by nitrate of silver. To the clear liquor, gently heated, carbonate of ammonia mixed 
 with caustic ammonia is to be added, to throw down all the barytes. The whole 
 is to be left in repose for a little till a granular precipitate falls, and it is then to 
 be thrown upon a filter and washed. The filtered liquor being evaporated to dryness, 
 the residuum is to be ignited in a platinum or silver capsule, to expel all the ammonia, 
 when it can contain only the alkaline metals, potassium and sodium, in the state of 
 chlorides. After being weighed, it is to be dissolved in a very little water, when a 
 trace of magnesia may appear (which can be eliminated and weighed) ; and the 
 amount of potash is to be estimated from the weight of the precipitate produced by 
 soda-chloride of platinum. The difference of the weight of the whole chloride and 
 of that corresponding to the potash just found gives the quantity of sodium-chloride, 
 and of course of soda in the soil. 
 
APPENDIX II. 
 
 ZINC PURIFYING. 
 
 311 
 
 TOBACCO. In confirmation of the justness of my remarks upon the equivocal 
 nature of the fermentation test adduced by the Excise chemists, as to the presence 
 of sugar in tobacco ( Supplement, pp. 255, 256.), I have now the satisfaction of quoting 
 the following experimental results obtained by Schlossberger and Dopping, in their 
 recent elaborate dissertation upon yeast: — " Out of yeast, by which sugar may be 
 decomposed, sugar itself may be easily formed. This fact ought, however, the less 
 to surprise us, since Piria has described a fermentation whereby sugar is formed out 
 of salicin with emulsin." * 
 
 It is also known to chemists, that in the fermentation of an infusion of bitter 
 almonds, or of a solution of 10 parts of amygdaline and 1 part of synaptase, in 110 
 parts of jwater, a greater quantity of sugar (as indicated by the alcohol formed) is ob- 
 tained, than what the elements carf^roduce. — See Liebig's Chimie Organique, I. 276. 
 
 ZINC PURIFYING, may be effected by melting the impure metal with lead in 
 equal parts in a deep iron pot, stirring them well together, skimming off the impurities 
 as they rise, covering the surface with charcoal to prevent oxidation, and keeping them 
 in a fused state for three hours. The lead descends to the bottom by its greater 
 density, and leaves the zinc above, to be drawn off by a pipe in the side of the melt- 
 ing-pot. This contrivance is the subject of a patent granted to Mr. William Godfrey 
 Kneller in 1844. 
 
 * " Es zeigt sich also hier das Paradox erscheinende Resultat, dass aus der Hefe, die den Zucker zer- 
 setzt, leicht selbst Zucker gebildet werden kann. Doch darf dieses weniger auffallen, seit Piria eine 
 Gahrung beschrieben hat, wobei Zucker gebildet wird aus Salicin mit Emulsin."—- dnnalen der Chemie 
 und der Pharmacie, von Wohler und Liebig, L. I. 208. 
 
 THE END. 
 
London : 
 Printed by A. Spottiswoode, 
 New-Street-Square.