CI PES 
 
 COMPILED FROM THE 
 
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WRINKLES 
 
 AND ^'^i'Y tk 
 
 RECIPES, 
 
 COMPILED PROM THE 
 
 Scientific American. 
 
 A Collection of Practical Suggestions, Processes, and Directions lor 
 
 THE MECHANIC, 
 
 THE ENGINEER, 
 
 THE FARMER, and 
 
 THE HOUSEKEEPER. 
 
 I1L.1L, u©tiia.tje:i>. 
 
 EDITED BT 
 
 p ^??^ Pi iv B E jsr J A Tvi I ]sr. 
 
 Revisers and ContriMors : 
 
 Professor R. H. THURSTON, C.E. 
 
 Professor P. H. VANDER TTEYDE, M.D. 
 
 RICHARD H. BUEL, Mechanical Engineer. 
 
 JOSHUA ROSE, Mechanical Engineer. 
 
 Xeav-York ; 
 
 TI. ?^. IVrXJNINr, FXJBLISHER, 
 3r Park Row. 
 
Entered according to Act of Congress, in the year 1875, by 
 
 H. N. MUNN AND PARK BENJAMIN, 
 in the Office of the T.ihrnrian of Congress, at Washington. 
 
 THEGEnYCENlER 
 LIBRARY 
 
If any worker in five great army of those in, 
 whose intelligent labor lies the surest foundation 
 for the prosperity of us all, finds among the sug- 
 gestions here compiled one tJvought, as it is hoped 
 he may many, ivhich shall lighten his toil or 
 aid him in the production of better work, then 
 the editor sincerely trusts that that worker will 
 deem this little volume as prepared, for his es- 
 pecial benefit, and to him especially dedicated. 
 
PREFACE. 
 
 The aim iu the following pages has been to compile a collec- 
 tion of suggestions for the every-day use of the workiug-man,in 
 his shop, about his dwelling, or in his household. The book is not 
 an encyclopaedia of recipes, nor does it make any pretensions to 
 that title ; on the contrary, a very large number of formulae have 
 purposely been omitted, because they are, for the most part, at- 
 tainable in other and more extensive works. Preference has been 
 given to practical hints, and, while the majority of these have 
 been carefully gathered and condensed from the back files of the 
 Scientific American, and more especially from the letters of cor- 
 respondents of that paper, a goodly proportion are entirely new 
 and fresh, and have been prepared expressly for this book. 
 
 For the contribution of a large part of the matter in, and for 
 the general supervision of the department of Mechanics, the edi- 
 tor is indebted to that thorough workman, Mr. Joshua Rose. To 
 Mr. Richard H. Buel (whose articles are signed " B.") similar ac- 
 knowledgments are owing for valuable papers on boilers, engines, 
 and other to|)ics in the department of Engineering. The general 
 revision of the last-mentioned department has been the labor of 
 Professor R. H. Thurston, of the Stevens Institute, as has the si- 
 milar overlooking of the department of Technology, that of Pro- 
 fessor P. H. Van der Weyde. To both of these distinguished 
 gentlemen, as well as to Messrs. Munn & Co., the publishers of 
 the Scientific American, who have most kindly afforded the facili- 
 ties for the preparation of this work, the cordial acknowledgments 
 of the editor are due. 
 
 New-Yokk, 1877. 
 
CONTENTS, 
 
 * 
 
 * 
 
 Subjects will he found arranged nlphahetically under the 
 
 below-indexed subheadings of the various departments. 
 
 Mechanics: p^ge 
 
 Master Tools and their Uses 7 
 
 Tools 16 
 
 Mechanical Shop Wrinkles and Directions . 38 
 
 Engineering: 
 
 Testing Materials 55 
 
 The Engine and its Appendages 57 
 
 The Boiler and its Attachments 87 
 
 Belts, Pulleys, and Sliafting 109 
 
 Practical Technology : 
 
 Cements, Glues, and Moulding Compositions 135 
 
 Metal-Working Hints and Kecipes 140 
 
 Simple Instrunii'uts and their Uses 150 
 
 Recipes for the Preparation of wood 156 
 
 The Preservation and Preparation of Natural History 
 Specimens 158 
 
 Painting, Ciilding, and Varnishing Recipes 166 
 
 Hints about Drawing and Sketching 171 
 
 Simi)le (lalvanic Batteries and Electroplating Recipes. . . .178 
 
 Useful Chemical Recipes for Detection of Adulterations, 
 etc 181 
 
 The Farm : 
 
 Farm Buildings 189 
 
 The Dairy 202 
 
 Farm Hints and Reciiies 204 
 
 Household Hints 223 
 
MECHANICS. 
 
 MASTER-TOOLS > THEIR MANUFACTURE AND 
 
 USE. 
 
 The master-tools, here illustrated and described, comprise all 
 that are necessary for plain machine- work in every description of 
 metal ; and if they are made of the precise shape, and according 
 to the given instructions, they will perform the full amount of 
 duty here allotted to them, which, though it may appear to be 
 unusually great, may be thoroughly relied upon for metal of any 
 ordinary degree of hardness. Xor can any less amount of duty 
 be obtained from them without evidencing inferior mechanical 
 skill either in making or using the tool. It is true economy to ob- 
 tain from a cutting tool its utmost amount of duty, which, though 
 it may entail a little more drawing out and grinding of the tool 
 in a given time, does not involve anymore as compared to the 
 quantity of work performed. It is well within the mark to say 
 that at least one third more duty, in a given time, may be ob- 
 tained from cutting-tools for metals (used in all machines having 
 variable speeds and feeds, such as the lathe and the shaping- 
 machine), than is obtained in the usual practice of our machine- 
 shops, especially in the larger ones. 
 
 Boring-tool for Brass. — The boring tool for brass-work, 
 here shown, is a standard tool for either roughing out or finish- 
 
 BORING-TOOL FOR BRASS. 
 
 ing, both of which duties it will perform equally well. It is bent 
 further round at the end than is the boring-tool for wrought-iron, 
 to prevent it from jarring or chattering. It is a master-tool in 
 ev^ery sense of the word. It should be hardened right out, and 
 used with a quick speed and light feed, no matter how deep the 
 
8 
 
 MECHANICS. 
 
 cut is. To prevent chattering or jarring when extending far out 
 from the tool-post, or when it is very slight in body, it should 
 have the toi) face depressed toward the cutting edge. When this 
 tool is a stout one, the point may be ground more round, which 
 will make it cut to finer finish. 
 
 BoHiNG-TOOL KOH Wrought-iron OR Steel. — For turning Out 
 small holes, the tool here represented has no equal, providing it 
 
 BORING-TOOI, FOR WROl'ClIT-IltON OH STEEL. 
 
 be made of the precise shape shown, the reasons for which are as 
 follows : The cutting end must not be bent, in forging, any fur- 
 ther round, because, in that case, the strain placed upon the tool 
 by the cut will be in a direction tending to revolve the tool in 
 the tool-post, giving the tool a corresponding tendency to spring 
 away from its cut ; and further, because so stout a tool could not 
 be got into the same size of hole. The degree of bend or angle 
 of the centre-line of the bent end to the centre-line of the length 
 of the body of the tool, causes the strain of the cut to be placed 
 comparatively endwise of the tool, endeavoring to force it back 
 into the tool-post, and thus ])lac('s flic strain in the direction in 
 which the tool is best caiJabU; of withstanding it. The keenness 
 and shape given to the top face of the tool make the cutting edge 
 perform its duty on the front edge, which again tends to place 
 the strain endwise on the tool, operating, by the strain on the top 
 face of the tool (caused by its bending tlie sliaviiig), to keep the 
 tool to its cut by giving it an inclination to fct-d itself forward, 
 thus rclifving tho feed-screw and nut of tlie slide-rest of a part 
 of tlie duty of f.-eding. The cutting edge should not, even when 
 tlie too] is newly forged, stand much, if any, above the horizontal 
 ydane of the top of the body of the tofd, otlierwise so stout a tool 
 can not be got into a given size of hole, a consideration which is 
 f)f the utujost importance ; because boring-tools, from their com- 
 parative slightness, especially in lotii: holes, are a|)t, under the 
 most favorable of conditions, to spring away from the cut as the 
 cutting proceeds toward tlie back end of the hole, thus making 
 the latter a tajier, of Avliich thi^ back end has the smalli'st diame- 
 ter, necessitating neveiiil line finishing cuts in order to mak«^ a 
 parallel hole. If, however, <'very means is taken to use as stout 
 a tool as the size of tlie liole will admit, the boring-tool will bore 
 u very true and smooth hole. 
 
MECHANICS. 
 
 9 
 
 In using these tools, it is best to employ a comparatively quick 
 speed and lio^bt feed, no matter what the depth of the cut may 
 be. They should be tempered to a very light straw if the tool is 
 slight, and otherwise hardened right out ; and the work should 
 be freely supplied with soapy water. For use on copper, the 
 top face should be ground more hollow, so that the cutting edge 
 will be much more keen than is here shown. Whenever there 
 is sutficient room in the hole, a stout bar of iron or steel should 
 be held in the tool-post, and a short tool secured by set-screw in 
 the end of the bar, thus securing greater rigidity than is pos- 
 sessed by a boring-tool, and facilitating the forging and grinding 
 of the cutting-tool 
 
 Finishing-Tool for Cast-Iron. — Cast-iron may be finished 
 true and smoothly by a tool having a much broader cutting and 
 scraping surface than is applicable to any other metal ; and we 
 are therefore enabled to apply to it, for finishing purposes, the 
 
 FINISHING-TOOL FOR CAST-ERON. 
 
 tool above illustrated, setting it so that its square nose is placed 
 quite parallel with the work, and feeding it with a feed almost 
 as coarse as the width of the square nose, say 8 revolutions of the 
 lathe per in. of tool travel on small work, and 3 revolutions per 
 ditto for large work. The tool is held with the cutting edge aa 
 close to the tool-post as can possibly be convenient, and the 
 cutting speed is about 25 to 30 feet per minute on small work, 
 and 18 feet on large work, the tool being hardened right out iu 
 all cases. 
 
 FiNisHixo-TooL for WRoroHT-lRON, Cast-Iron, or Steel.— 
 This is a finishing-tool for wrought-iron which will cut smoothly, 
 clean, and true, beinir far preferable to the square-nosed tools 
 sometimes used for the purpose of finishing iron, since such tools 
 do not turn wrought-iron true, but follow the texture of the 
 metal, cutting deepest in the softer parts, especially when their 
 edges become in the least dull from use. This tool should be 
 
10 
 
 MECHANICS. 
 
 held with the cutting edge as close in to the tool-post or clamp as 
 it can conveniently be, with a quick speed and fine feed, soapy 
 water being applied to the work. It may be also used for taking 
 light roughing cuts on small work, and is, for such purposes, 
 an excellent tool, especially upon work so slight as to be liable 
 to spring, for which purpose the cutting point should not be 
 much rounded. Ground very keen, it will answer admirably for 
 copper work, the cutting speed being very great ; that is to" say, 
 at least fourfold that given below, which is for finishing cuts on 
 wrought or cast iron. 
 
 FINISHrNG-TOOL FOR WROUGHT-IRON, CAST-IRON, OR STEEL. 
 
 Size of work, 
 inches diameter. 
 
 1 and less 
 
 1 to 3 
 
 2 " 5 
 5 " 12 
 
 12 " 30 
 20 and over 
 
 (-'lUtiiii; jiijood, 
 feet per minute. 
 
 38 
 30 
 25 
 23 
 20 
 18 
 
 Peed. 
 
 30 
 25 
 20 
 20 
 16 
 14 
 
 This tool should always be hardi-ned right out ; and if used 
 upon cast-iron, it should have less keenness upon tlie toj) face ; 
 that is to say, the i)lane of the top face should be ground more 
 nearly to the same plane as the top face of the body ()f the tool. 
 For use upon steel, the top face must be ground more nearly 
 horizontal — a rule which, we tiuiy hereoljservc, applies to all tools 
 used upon wMuglit-iron. It sliould be placed in the lathe so 
 tliat its cutting edge stands above the horizontal centre-line of the 
 work. 
 
 FnoNT-Toor- kok Bhass-Wouk.— This is a complete master- 
 tool, filling every necessary <|iialillcati<)ii for all plain outside 
 l)rass work, ami dointr the duty on lliat metal wliicli the front 
 tnol nrid right and left hand side-tools do on wrought iron. As 
 shown in the engraving, it is ground to suit either roughing out 
 
MECHANICS. 
 
 11 
 
 or finishing. For very sliglit work, wbicli is liable to spring, it 
 may be ground a little more keen on the side faces, the top face 
 not' requiring, under any possible circumstances or conditions, to 
 be o-round keener than shown above. When held far out from 
 the^'tool-post, the top face sliould be ground away, sloping down 
 toward the cutting edge, wliich is done to prevent the tool from 
 jarring or chattering. It should be hardened right out, and not 
 
 FRONT-TOOL FOR BRASS-WORK. 
 
 lowered or tempered at all, and used for roughing out at the 
 following speed and feeds : 
 
 Size of work, 
 in inclies. 
 
 1 and less 
 
 2 to 5 
 5 to 13 
 
 12 to 20 
 
 Revolutions of Lathe. 
 
 350 
 250 
 200 
 150 
 
 Peed. 
 25 
 25 
 35 
 30 
 
 For finishing-cuts, the cutting speed may be increased by 
 about one fifth, which rule will also apply to its use upon yellow 
 brass for roughing out as well as finishing purposes. 
 
 PARTING-TOOL. 
 
 Parting or Grooving Tool for Iron or Steel. — The part 
 ing tool is applicable either to cutting grooves or for parting, or, in 
 other words, cutting work aj)art. The cutting point, or end of the 
 tool, is made thicker than the metal, both vertically and horizon- 
 tally, behind it, so that the latter shall clear and not grind against 
 the sides of the groove. This tool, especially if made thin to suit 
 some especial purpose, is excessively liable to spring, in conse- 
 quence of the pressure of the cut ; and if it commences to spring, 
 it is apt to dig into the cut, and then break from the excessive 
 
12 
 
 MECHANICS. 
 
 Strain. It is to prevent this digging in that the top face of the 
 cutting part of the tool is placed so much below the top face of 
 the body of the tool, which may, however, be dispensed with when 
 the cutting edge is held close in to the tool-post, and the groov- 
 ing is not required to be very deep. When, however, these re- 
 quirements do exist, the form illustrated is absolutely indispen- 
 sable to rapid and reliable duty, whether the tool be used in a 
 lathe or a planiug-machine, the cutting edge of the tool being 
 kept at about the horizontal centre of lathe-work, by packing- 
 pieces placed beneath the body of the tool. If the width of the 
 tool is not less than ,^^ inch, and does not require to cut a groove 
 deeper than f inch, it should be hardened right out ; if, however, 
 these conditions are reversed, it should be tempered to a dark 
 straw, and for very weak tools even to a purple color, as lower- 
 ing the temper increases the strength of all tools. If the groove 
 to be cut is sufficiently broad to cause the tool to spring, it is 
 best to use a narrower one and cut it out in two separate cuts, 
 moving the tool. 
 
 PARTING-TOOL FOU BnA.*S. 
 
 Parting-Tool for Br.\ss. — The parting-tool for braes is gov- 
 erned by the same principle as that for iron, save that its top face 
 must be ground level, except in cases where the cutting edge 
 stands far out from the tool-post, in which event the toj) face 
 
 KOl'OIIINO-TOOL FOH WUOIKillT-IUON. 
 
 must be ground away at an angle of which the cutting edge is 
 flie lowest i)iirt. It is rarely, liowever, necessary for brass-work 
 to grind tlie cutting edge imich below tin- level of tlie to]) face of 
 the bo<ly of the tool, as is sliowti lor use on wroiight-iroii. 'Die 
 
MECHANICS. 
 
 13 
 
 degree of hardness of the tool should be the same for brass as 
 that given for wrought-iron. 
 
 ROUGHING-OUT Front Tool FOR Wrought-Iron.— Tlie en- 
 graving represents the best possible form of tool for roughing 
 out wrought-iron, or for removing a large mass of that metal in 
 the lathe or planing-uiachine. When used on large work, it 
 should be tempered to a light straw-color, which will leave it 
 strong enough to stand without breaking the heavy strain due to 
 the cut. It must be held very firmly, and with the cutting edge 
 as close to the tool-post as it can well be. 
 
 The following are its rates of cutting speed and feed, the speed 
 meaning the length of shaving it cuts off, and the feed implying 
 the number of revolutions of the lathe necessary to feed the tool 
 an inch along its cut : 
 
 Size of work. Cutting speed, Yeed 
 
 inches diameter. feet per minute. 
 
 1 and less 35 25 
 Ito 2 25 20 
 
 2 " 5 20 20 
 5 " 12 18 15 
 
 12 " 20 16 13 
 
 20 and over 15 12 
 
 For work of five inches diameter, and for all sizes below that, the 
 tool should be hardened right out ; that is, made as hard as fire 
 and water will make it, and not tempered at all. For work of a 
 larger size, it should be tempered to a light straw-color. This 
 tool, with the top face ground less keen, that is, more nearly 
 horizontal, is an excellent one for steel, and the harder the metal 
 to be cut, the more nearly horizontal the to]) face must be. It 
 should be placed, for lathe- work, so that the cutting edge stands 
 a little above the horizontal centre-line of the work. 
 
 SIDE-TOOL FOR BRASS. 
 
 Side-Tool for BRASS.^This tool fills the same place with re- 
 ference to that metal that the side-tool and knife-tool do to iron- 
 work ; and it has no superior for taking out corners, for cutting 
 out holes or recesses which do not pass entirely through the 
 metal. In conjunction with the front-tool for brass, already il- 
 lustrated, it will perform almost any duty upon either inside or 
 outside brass-work, except, of course, cutting out narrow grooves. 
 Its cross-section is somewhat diamond-shaped, and it is made 
 right and left by bending in opposite directions. It is a far better 
 tool than those bent round at the end after the manner of a Ijor- 
 
14 
 
 MECHANICS. 
 
 ing-tool ; and being more rigid, it is easier to forge and grind, and 
 less liable to jar or chatter. It is equally applicable as aroughing- 
 out or a finishing tool. It should be hardened right out, and 
 used at the speeds and feeds given for the front-tool for brass. 
 
 PIDE-TOOI. KOK sglMllNL; ENDS OF ■\VKOCGHT-IR0N WORK. 
 
 Side- Tool for Squ.\uing Ends op Wrougiit-Iron Work. — 
 The illustration represents a side-tool for wrought-iron, to be 
 employed for squaring the ends of work held between the lathe 
 centres, and in other cases wherein there is not sufficient room to 
 admit a stouter tool. The cutting edge is shown at A, and .should 
 be made more keen for wrought than for cast iron. In forging 
 it, the hammering edgewise should be performed first, nor should 
 any lianmiering be done to it edgewise after the steel lias lost 
 its redness. It should, for light duty, and for all finishing pur- 
 poses, be hardened right out, and, for heavy duty, be tempered to 
 a straw-color. If, liowever, this tool is employed, as it some- 
 times is, for very heavy duty on aslotting-machine, taking a cut, 
 say, 2^ inches deep and \ inch thick, it must be lowered to a 
 brownish purple and used at a cutting speed of about 10 feet per 
 minute, and be ground so that the cutting edge first strikes the 
 cut near the body of the tool, and not at the point end. For ordi- 
 nary work, it is best used with a comparatively fine feed and 
 quick speed, since it is not sufficiently strong, when made very 
 hard, to stand heavy duty. 
 
 SIDE-TOOI, roil IKON. 
 
 SidkTooi, koh WRoufiHT Ikon, <'ast-Ii{()N, ok Stkrt.. — The 
 engraving represents tlu; most superior side-tnoi for eitlier wrought 
 or cast iron or steel, the only difTeniUce being that it requires to be 
 less keen for tlie hitter than, as here hIkuvu, for tlie former. It la 
 
MECHANICS. 
 
 15 
 
 employed to cut side-faces and to take out round or square cor- 
 ners. For small work, it should be made so that it will cut at 
 the point, and not on both edges at one time, when used in a 
 square corner. For heavy work, it may be made more round-nosed, 
 and allowed to cut all round the curve ; and it will, in either 
 shape, work equally well as a roughing-out or as a finishing tool, 
 only requiring to be ground more keen to fit it for finishing pur- 
 poses (which should be, on wrought-iron, performed with soapy 
 water applied to the work), and at a faster speed and finer feed. 
 For taking out a round corner or fillet in slight work, which is 
 liable to spring from the pressure due to the cut, the point must 
 be rounded very little, the curve being made by operating both 
 the straight and cross feeds of the lathe. This tool is made right 
 or left handed by simply bending it in the required direction, 
 that illustrated being a left-hand tool. It should be made as 
 hard as fire and water will make it, and used at the following 
 speeds and feeds : 
 
 iameter of woi 
 
 ■k, 
 
 Speed, in 
 
 "P'pPfl 
 
 in inches. 
 
 
 feet, per mtnute. 
 
 J: ecu. 
 
 1 and less 
 
 
 30 
 
 30 
 
 1 to 2 
 
 
 25 
 
 25 
 
 2 " 5 
 
 
 22 
 
 20 
 
 5 " 12 
 
 
 20 
 
 20 
 
 When, however, it is employed for roughing-out purposes, these 
 speeds may be, with advantage, slightly diminished and the feeds 
 increased. 
 
 SPRING-TOOL. 
 
 Spring-Tool for Use on Wrought-Iron, Cast-Iron, Steel, 
 OR Br.\ss. — The spring-tool is especially adapted to finishing 
 sweeps, curves, or round or otlier corners, and will answer for 
 any metal whatever. As illustrated, the fiice is given an up 
 ward incline to make it sufficiently keen for wrought-iron or 
 steel. For brass-work, this face should be made horizontally 
 level, or, if the cutting stands with its cutting edge far out from 
 the tool-])ost, it may be inclined downward to make it cut 
 smoothly. The piece of wood shown driven in the bend is to 
 correct any tendency of the tool to s]iring away from the hard 
 
16 
 
 MECHANICS. 
 
 parts of the metal, as it is apt to do. The spring-tool does not 
 turn so true as is desirable, still the smoothness of its finish 
 makes it the most desirable tool for tlie purposes mentioned. It 
 should have its face filed up very smoothly before bein<j 
 hardened, and should not be ground on that face. The applica- 
 tion of the oilstone greatly improves its value for finishinfr. It 
 should, for all purpose, be tempered to a brown color on the face, 
 and left soft around the bend. 
 
 TOOLS. 
 
 Borino-Bar for Lathe- Work. — In boring work chucked 
 and revolved in the lathe, such, for instance, as axle-boxes for lo- 
 comotives, the boring-bar here shown is an excellent tool. A 
 represents a cutter-head, which slides along, at a close working 
 fit, upon the bar, D D, and is provided with the cutters, B B B, 
 
 BORINH-BAR. 
 
 whicli are fastened into slots jjrovidcd in the head, A, by the keys 
 shown. The bar, \) D, has a thread cut ui)on part of its length, 
 ilie remainder being plain, to fit the sliding head. One end is 
 squared to receive a wrench, which, resting against the bod of the 
 lathe, jiri'VentB the barfroni revolving upon the lathe centre, F F, 
 by wliich the bur is held in the lathe. (J (i (» are plain washers, 
 jtrovided to make iij) tht; distance between th(^ thread and ])lain 
 part of th<^ bar, in cases wIkmo the sliding liead, A, requires con- 
 siderable lateral movement, there being more or fewer washers 
 employed accorcliiig to the distance along whicli the sliding head 
 is re<|uired to move. The edtres of these washers an; chamfered 
 off to ])reveiit them from burring easily. To fe(>d the cutters, the 
 iMit, II, is sirewed up with a wren<h. 
 
 '{'he cutter head, A, is provided in its bore with two feathers, 
 wliicli slide in grooves i)rovided in tlm bar, D 1), thus prevent- 
 ing the hea<l from revolving upon the bar. It is obvious that 
 
MECHANICS. 
 
 17 
 
 tliis bar will, in consequence of its rigidity, take out a mucli 
 heavier cut than would be possible with any boring-tool, and 
 furthermore that, there being four cutters, they can be fed up 
 four times as fast as would be possible with a single tool or cut- 
 ler. 
 
 Boring-Tools, Shapes of.— The pressure on the cutting edge 
 of a tool acts in two directions, the one vertical, the other lateral. 
 The downward pressure remains at all times the same ; the 
 lateral pressure varies according to the direction of the plane of 
 the cutting edge of the tool to the line or direction in which the 
 tool travels : the general direction of the pressure bein^ at a 
 right angle to the general direction of the plane of the cutting 
 edge. For example, the lateral pressure, and hence the spring 
 of the various tools, shown in the cut, will be in each case in 
 the direction denoted by the dotted lines. D is a section of a 
 piece of metal requiring the three inside collars to be cut out ; 
 
 LATEBAL PRESSURE OP TOOLS. 
 
 A, B, and C are variously shaped boring-tools, from which it will 
 be seen that A would leave the cut in proportion as it suffered 
 from spring, which would increase as the tool edge became dull, 
 and that the cut forms a wedge, tending to force the tool toward 
 the centre of the work. B would neither spring into nor away 
 from the cut, but would simply require more power to feed it as 
 the edge became dulled ; while C would have a tendency to run 
 into the cut in proportion as it springs ; and as the tool edge be- 
 came dull, it would force the tool-point deeper and deeper into 
 the cut until something gave way. Now, in addition to this con- 
 sideration of spring, we have the relative keenness of the tools, 
 it being obvious at a glance that (independent of any top rake or 
 lip) C is the keenest and A the least keen tool ; and since 
 wrought-iron requires the keenest, cast-iron a medium, and brass 
 the least keen tool, it follows that we may accept, as a rule, C for 
 wrought iron. B for cast-iron, and A for brass-work. In Fig. 2, B 
 represents a section of the work, No. 1 represents a boring-tool 
 with top-rake, for wrought-iron, and No. 2 a tool without top- 
 rake, for brass-work, which niny be also used for cast-iron when 
 the tool stands a long way out from the tool i)Ost or clamp, under 
 which circumstances it is liable to jar or chatter. A tool for use 
 
18 
 
 MECHANICS. 
 
 on wrouglit-iron should have the same amount of top-rake, no 
 matter how far it stands out from the tool-post ; whereas one for 
 use on cast-iron or brass requires to be the less keen the further 
 it stands out from the tool-post. To take a very smooth cut on 
 brass-work, the top face of the tool, shown at 3 in Fig. 3, must 
 be ground off, as denoted by the dotted line. 
 
 We have now to consider the most desirable shape for the 
 corner of the cutting edge. A positively sharp corner, unless for 
 
 Kiii. i. 
 
 a Bperial j)urposo, is very und<'siral)I<', Ijccausc the (extreme point 
 soon wears iiway, leaving the ctitting (jiiaiilication (rf the tool 
 almost di'Hlroyt'd, and l)ccaii.st! it Icuvch the work rough, and can 
 only i)e employed with a very fine feed. It may l)e aciej)ted as a 
 general ruh^ tluit, for roughing cuts, till- ciiini-r should be suili- 
 ci.Mitly rounded to give strength to thf lool-jKjint ; while, in 
 fini.-hiMir <iitH, the point may be nnidr as round us jtossibh! with- 
 out ciinsin^Mhr tool to jar or chati.T. Now, sinn- the tendency 
 
MECHANICS. 
 
 19 
 
 of the tool to jar or chatter depends upon four points, namely, 
 the distance it stands out from the tool-post, the amount of top- 
 rake, the acuteness or keenness of the general outline of the tool, 
 and the shape of the cutting corner, it will he readily seen tliat 
 
 FIG. 3. — VARIOUS FORMS OF BORING-TOOLS. 
 
 judgment is required to determine the most desirable form for any 
 particular conditions, and that it is only by understanding the 
 principles governing the conditions that a tool to suit them may 
 be at once formed. In Fig. 3 will be fouud the various forms of 
 boring-tools for ordinary use. No. 1 is for use when the condi- 
 tions admit of a heavy cut on wrouglit-iron. No. 2 is for use on 
 wrought-iron when the tool stands so far from the tool-post as to 
 be necessarily subject to spring. No. 3 is to cut out a square 
 corner at the bottom of a hole in wrought-iron. No. 4 is for 
 taking out a heavy cut in cast-iron. No. 5 is for taking out a 
 finishing cut in cast-iron when the tool is proportionally stout, 
 and hence not liable to spring or chatter ; the point being flat, 
 the cutting being performed by the front corner, and the back 
 part being adjusted to merely scrape. No. 6 is for use on cast- 
 iron under conditions in which the tool is liable to jar or spring. 
 
 Chilled Cast-Iron Tools, To cast, for cutting chilled iron. — 
 Make a tool of the required shape out of wrought iron, then case 
 the chilled part, using charcoal-iron No. 5. 
 
 Chipping.— The chisel requires special notice since it is fre- 
 quently made of the most ill-advised shape (for either cutting 
 smoothly or standing the effects of the blow), that is, hollow, as 
 in Fig. 1, in which case there are two sections f)f metal, repre- 
 sented by the dotted lines, a a. which are very liable to break, 
 from their weakness and from the strain outward placed upon 
 them by the cut, which, acting as a wedge, endeavors at each 
 blow to drive thcni outward instead of inward, as would be 
 
20 
 
 MECHAJaCS. 
 
 the case in a properly shaped chisel, as shown iu Fig. 3, a being 
 the cutting edge. 
 
 When using, hold it firmlv against the cut, and it will do its 
 work smoother and quicker. 
 
 The cape, or, as it is sometimes called, cross-cut chisel, is em- 
 ploN-ed to cut furrows across the work to be chipped, which fur- 
 rows, being cut at a distance from each other less in width than 
 the breadth of the flat chisel, relieve the flat chisel and prevent its 
 corners from " digging in" and breaking. If a large body of 
 metal requires to be chipped ofE cast-iron or brass, the use of the 
 
 
 •a. 
 
 a 
 
 riti. 1. 
 
 FIG. 2. 
 
 COLD CHISELS. 
 
 cape-chisel becomes especially advantageous, for the metal, being 
 weakened by the furrows, will break away in pieces from the force 
 of the blow, without requiring to be positively cut by the chisel ; 
 but care must be tukeu to leave sufficient metal to take a clean 
 finishing cut ; for when the metal is broken away, by the force of 
 the blow, it is ai)t to break out below the level of the cut. It is 
 also necessary to nick deeply with a chisel the outside edges of 
 the work at the line representing the depth of the metal to be 
 chipped off, so that the metal shall not break away at the edges 
 deeper than the cut is intended to be. 
 
 Chisels, Cold, To grind. — Grind a cold-chisel so that its cut- 
 ting edge is rounding and not hollow, as it is often made. A 
 rounded chisel is stronger and cuts smoother. A hollow chisel 
 has no useful place as a chipping-tool. 
 
 Chisels, Cot.d, To harden. — Heat the chisel to a distance about 
 equal to its width, immerse it about half that distance in the wa- 
 ter, hold it still about four seconds, suddenly dip it a little 
 deeper, and then withdraw. Urightt n one flat surface with a 
 I)iece of grindstone or an cniery-block ; then l)rnsh the hand or a 
 piece of waste over the brightened surface to remove Ww false 
 color, and finally cool out in the water, when the clear blue color 
 api)ears. 
 
 CiilsPM.H, C<ti,i), To hold. — IIolil u cold-chisel firmly to its cut, 
 without removing it at every blow. This will incr<-iise its effec- 
 tiveness, and decrease its liability to break from a foul blow. 
 
 CliisKi.H, Cold, To remove burrs from the heads of. — When 
 tlie head of a cold-cliisrl is burn d over from use, rest the head 
 ujnm a l>lock of iron, and strike tin- burrs from the under side, 
 and tiny will l)r<'!ik n-adily and easily olT. 
 
MECHA^^cs. 
 
 21 
 
 Chisels, Cold, Use of. — These sliould be kept thin at the cut- 
 ting end, which saves time and entails less labor in using. 
 
 Cone-Plate for boring in the lathe. — For chucking shafts and 
 other similar work in tbe lathe (to bore holes in the ends of the 
 shafts, etc.), the cone-plate shown in the engraving is the best 
 appliance known to machinists. A is a standard, fitting in the 
 shears of the lathe, at E, and holding the circular plate, C, by 
 means of the bolt, B, which should be made to just clamp the 
 plate, C, tightly when the nut is screwed tight. The plate con- 
 tains a series of conical holes, 1, 2, 3, etc. (shown in section at D). 
 The object of coning the pin, B, where it carries the plate, C, is 
 that the latter shall be made to a good working fit and have no 
 play. The operation is to place the shaft in the lathe, one end 
 being provided with a driver, dog, or carrier, and placed on the 
 running or line centre of the lathe ; and the other end, to be 
 
 CONE-PLATE FOR BORING Df THE LATHE. 
 
 operated upon, being placed in such one of the conical holes of 
 the plate, C, as is of suitable size, the distance of the standard, 
 A, from the lathe-centre is to be adjusted so that the work will 
 revolve in the coned hole with about as much friction as it would 
 have were it placed between both the lathe-centres. Thus the 
 conical hole will take the place of the dead-centre of the lathe, 
 leaving the end of the shaft free to be operated on. F F are 
 holes to bolt the standard, A, to the lathe shears or bed ; and G 
 G, etc., are taper-holes to receive the pin, G, shown in the sec- 
 tional view. The object of these holes and pin is to adjust the 
 conical holes so that they will stand dead true with the lathe- 
 centres ; for if they stood otherwise, the holes would not be 
 bored straight in the work. In the engraving, hole No. 7 is 
 shown in position to operate, the pin, G, locking the plate, C, in 
 that position. In setting the work, the nut on the pin, B, should 
 be eased back just sufficiently to allow the plate. C, to revolve 
 by hand ; the work should then be put into position, and the pin, 
 G, put into place ; the standard. A, should then be adjusted to 
 
Q2 
 
 MECHANICS. 
 
 its distaiKM' from till- live liillif-centre, and bolted to tlie lathe- 
 bed ; and linally, the nut on the pin, B, should be screwed up 
 tight, when the work will l)e held true, and tlie cone-plate pre- 
 vented from f^pringing. Care must be taken to t^upply the coni- 
 cal holes, in which the work revolves, with a liberal quantity of 
 oil, otherwise they will be apt to abrade. 
 
 Cutters and Reamers, To prevent, cracking when being 
 hardened. — Drill a small hole from tlie side to meet the large one 
 at its enclosed termination. 
 
 Cutters for Boiler-Platr and similar Work.— Cutters are 
 steel bits, usually held in either a stock or bar, being fitted and 
 keyed to the same ; by this means, cutters of various shapes and 
 sizes may be made to fit one stock or bar, thus obviating the ne- 
 cessity of having a multiplicity of these tools. Of cutter-stocks, 
 whicli are usually employed to cut out holes of comparatively 
 large diameter, as in the case of tube-plates for boilers, there are 
 two kinds, the simplest and easiest to lie made being tliat shown 
 below. 
 
 Cl'TTBRt:. 
 
 A is the stock, through wiiich runs a slot or keyway into which 
 th(! cutter, ii, fits, being locked by tlie key, (". D is a pin to 
 steady tlu; tool while it is in operation. Holes of the size of the 
 pin, f), are first drilled in the work, into which the ])in fits. To 
 obviate the nectissity of drilling these holes, somc^ modern drill- 
 stocks Imve, in place of the pin, D, a conical-ended pin which acts 
 as a centre, and which fits into a centre punch mark made in the 
 eenfre of the hole to be cut in the woi'k Most of these devices 
 are patenteil, and the in'mciple u|)oii which they act will be un- 
 derstoo'i from the second enf-raving, A being the stock to whicli 
 
MECHANICS. 
 
 23 
 
 the cutters, B B, are bolted with one or more screws. (' is a spiral 
 spring working in a hole in the stock to receive it. Into the out- 
 er end of this hole fits, at a working fit, the centre, D, wliich 
 prevented from being forced out (from the pressure of the spring 
 
 IS 
 
 CUTTERS. 
 
 C) by the pin working in the recess, as shown. E is the plate to 
 be cut out, from which it will be observed that the centre, D, is 
 forced into the centre-punch mark in the plate by the spring, C, 
 and thus serves as a guide to steady the cutters and cause them to 
 revolve in a true circle, so that the necessity of first drilling a 
 hole, as required in the employment of the form of stock shown 
 in the first figure, is obviated. 
 
 Cutting Square Threads, Tools for.— For cutting square 
 threads, the tool here represented is used. The point at C is 
 
 JicrJ4>. 
 
 'T 
 
 TOOL Foil CUTTING SQUARE THREADS. 
 
 made thicker than the width at D, so as to give the sides clear- 
 ance from the sides of the thread. At B it is made thinner, to 
 give the tool clearance, and deeper to compensate in some mea- 
 sure for the lack of substance in the thickness. The top face 
 
24 
 
 MECHANICS. 
 
 may, for wrought-iron or steel, be ground hollow, C being the 
 liifihest point, to make it cut cleaner ; while, when held far out 
 from the tool-post for use on brass-work, the face, C D, may be 
 ground at an incline, of which C is the lowest point, which will 
 prevent the tool from springing into the work. 
 
 If the pitch of the screw to be cut is very coarse, a tool nearly 
 one half of the width of the space between one thread and the 
 next should be employed, so as to avoid the spring which a tool 
 of the full width would undergo. After taking several cuts, 
 the tool must be moved laterally to the amount of its width, and 
 cuts taken ofE as before until the tool has cut somewhat deeper 
 than it did before being moved, when it must be placed back 
 again into its first position, and the process repeated until the re- 
 quired depth of thread is attained. 
 
 Sr-KEW ni'RINr. ctjttino 
 
 The abov(> figure represents a thread or screw during the above- 
 described ))n)cess of cutting, a a a\s the groove or space taken 
 out by tilt! cuts liefore the tool was moved ; B B represents tlie 
 first cut taken after it was moved ; c is the point to which the 
 cut, B, is supposed (for the purpose of this illustration) to have 
 traveled. 
 
 The tool used liaviiig been a little less than one half the proper 
 width of th(! space <>f the tliread, it becomes evident that the thread 
 will be l(!ft with ratluT more than its jiroprr thickne.s.x, wliicli is 
 done to allow finishing-cuts to be taken uj)on its sidi'S. for which 
 purpose the knife-tool already described is brought into requisi- 
 tion, care being taken that it is placed true, so as to cut i)()th 
 sides f)f the tliread of an cfiual angle to the centre-line ot the 
 Kcr(!w. 
 
 AfljuKtdhle dies, tliat is, those which take nion^ than one cut to 
 make a full tliread, should never be used in cases where a solid 
 die will answer the jturpose, because adjustable dies take every 
 cut at a (lifTerent angle to the ceiitre-liiie of the bolt, as ex]ilaiiied 
 by the following engravings. 
 
 Tlie first re]>resents an ordinary screw. It is vvident that the 
 ))itcli from (I to B is the same as from (' to D, tlu; one being the 
 to]), the otlier the liottom, of the thread. It is also evident that a 
 piece of cord wound once around tlie top of the thread will be 
 longer than one wound once around tlie bottom of the thread, 
 
MECHANICS. 
 
 25 
 
 and yet, in passing once around tlie thread, the latter advanced 
 as much forward as the former, that is, to the amount of the 
 pitch of the thread. To illustrate this fact, let a b, in the follow- 
 ing diagram, represent the centre-line of the bolt lengthwise, and 
 
 B a 
 
 ORDINARY SCREW. 
 
 c d a, line at right angles to it ; then let from the point e to the 
 point /represent the circumference of the top of the thread, and 
 from e to g the circumference of the bottom of the thread, the 
 lines 7i 7i representing their respective pitches ; and we have the 
 line k as representing the angle of the top of the thread to the 
 centre-line, a b, of the bolt, and the line I as representing the 
 angle of the bottom of the thread to the centre-line, a b, of the 
 bolt, from which it becomes apparent that the top and the bot- 
 tom of the thread are at different angles to the centre-line of the 
 bolt. The tops of the teeth of adjustable dies are themselves at 
 the greatest angle, while they commence to cut the thread on the 
 bolt at its largest diameter, where it possesses the least angle, so 
 
 Ch 
 
 that the dies cut a wrong angle at first, and gradually approach 
 the correct angle as they cut the depth of the thread. From what 
 has been already said, it will be perceived that the angle of 
 thread cut by the first cuts taken by adjustable dies, is neither 
 that of the teeth of the dies nor that required by the bolt, so that 
 the dies can not cut clean because the teeth do not fit the grooves 
 they cut, and drag in consequence. 
 
26 MECHANICS. 
 
 Dies for use in hand-stocks are cut from hubs of a larger dia- 
 meter than the size of bolt the dies are intended to cut : this being 
 done to cause the dies to cut at the cutting edges of the teeth 
 which are at or near the centre of each die, so that the threads 
 on each side of each die act as guides to steady the dies and pre- 
 vent them from wabbling, as they otherwise would do ; the result 
 of this is that the angle of the thread in the dies is not the cor- 
 rect angle for the thread of the bolt, even when the dies are the 
 closest together, and hence taking the finishing-cuts on the thread, 
 although the dies are nearer the correct angle when in that posi- 
 tion than in any other. A very little practice at cutting threads 
 with stocks and dies will demonstrate that the tops of the 
 threads on a bolt cut by them are larger than was the diameter 
 of the bolt before the thread was commenced to be cut, which 
 arises from the pressure placed on the sides of the thread of the 
 bolt by the sides of tlie thread on the dies, in consequence of the 
 difference in their angles ; which pressure compresses the sides 
 of the bolt-thread (the metal being softer than that of the dies), 
 and causes a corresponding increase in its diameter. It is in con- 
 sequence of the variation of angle in adjustable dies that a square 
 thread can not be cut by them, and that they do not cut a good 
 V-thread. 
 
 In the case of a solid die, the teeth or threads are cut by a hub 
 the correct size, and they therefore stand at the proper angle ; 
 furthermore, each diameter in the depth of the teeth of the die 
 cuts the corresponding diameter on the bolt, so that there is no 
 strain upon the sides of the thread save that due to the force ne- 
 cessary to cut the metal of the bolt-thread. 
 
 Cutting versus Sckaping Tools. — A tool will either cut or 
 scrape, according to the position in whidi it is held, as. for in- 
 stance, below the line A in the illustration. Line A is in each 
 
 CUTTING AND SCRAPINO. 
 
 casi! onf drawn from tlie centre of tlu! work to th(! jjoint of con- 
 tact betwe(!ii tin; tool edge and tlie work, (' being tlie work, and 
 
MECHANICS. 
 
 27 
 
 B the tool. It will be observed that the angle of the top face of 
 the tool varies in each case with the line A. In position 1, the 
 tool is a cutting one ; in 2, it is a scraper ; in 3, it is a tool which 
 is a cutter and scraper combined, since it will actually perform 
 both functions at one and the same time ; and in 4, It is a good 
 cutting tool, the shapes and angles of the tools being the same in 
 each case. 
 
 Dies, Fitting, to quadrants when either the dies or quadrants, 
 or both, are to be hardened. — -Make them a shade too small, to al- 
 low for their swelling during the process of hardening. 
 
 Dies, To ease hardened, that fit too tightly. — Supply them 
 with very fine emery and oil, and work them backward and for- 
 ward in their place along the travel. 
 
 Dies, To renew worn-out. — Slightly close the holes by swaging, 
 fill the clearance-holes with Babbitt-metal, and recut them with 
 the hub. 
 
 COUNTERSINK-PnSf DRILLS. 
 
 Drills, Countersink-Pin. — Of these tools there are various 
 forms. The following figure represents a taper countersink such 
 as is employed for holes to receive flush rivets or countersunk 
 head-bolts, this form of tool being mainly employed for holes above 
 1^ of an inch in diameter. It should be made, tempered, and used 
 as directed for pin-drills. In tempering these tools, or any others 
 having a pin or projection to serve as a guide in a hole, the tool 
 should be hardened right out from the end of the pin to about f of 
 an inch above the cutting edges. Then lower the temper of the 
 metal (most at and near the cutting-edges), leaving the pin of a 
 light straw-color, which may be accomplished by pouring a little 
 
28 
 
 MECHANICS. 
 
 oil upou it during the lowering or tempering process. The object 
 of this is to preserve it as much as possible from the wear due to 
 its friction against tlie sides of the hole. For use on wrought-irou 
 and steel, this countersink (as also the piu-drill) may have the 
 front face hollowed out, after the fashion of the lip-drill, and as 
 shown by the dotted line. 
 
 Drills, Slot, for key ways. — For drilling out oblong holes, such 
 as key ways, or for cutting out recesses such as are required to re- 
 ceive short feathers in shafts, the drill known as a slotting-drill, 
 here shown, is brought into requisiiion. No. 1 is the form in 
 
 EDGE VIEW 
 
 tND VIEW 
 
 ^J\/Pl. £ 
 
 END VIEW 
 
 A A 
 
 EDGE VIEW SIDE VIEW 
 
 rifl. 1.— HI.0T-DRI1.L8. 
 
 which this tool was employed in tlie early days of its introduc- 
 tion ; it is thtr Htrongi^r form of the two, and will tak(^ the heaviest 
 cut. 'J'iie ol)j('ctioti to it, liowevor, is that, in cutting out deep 
 slots, it is !ipt to drill (lut of true, the hoh' gradually running to 
 one side. Tlur iiictlioil (»f u.sing tlicse drills is to move tlu^ work 
 Inick and forth, in a chuck i)rovided for the ])urpose, the drill re- 
 maining .stationary. If these tools were used as common drills, 
 they would cut lioles of the form shown in Fig. 2. 
 
 FiLKs, TIk? use of. — In draw-liliug, take short, quick strokes, 
 which will prevent the file from iiinning and scratching. Long 
 
MECHANICS. 
 
 29 
 
 strokes, no matter how long the work may be, are useless save to 
 make scratches. Remember that it is less tlie number of strokes 
 you give the tile than the weight you place upon it that is effec- 
 tive ; tlierefore, when using a rough tile, stand suflaciently away 
 from the vise to bring the weight of the body upon the forward 
 stroke. New files should be used at first upon broad surfaces, since 
 narrow edges are apt to break the teeth if they have the fibrous 
 edges unw'orn. For brass- work, use the file on a broad surface 
 
 FIG. 2.— SLOT-DRILLS. 
 
 until ts teeth are dulled, then make two or three strokes of the 
 file under a heavy pressure upon the edge of a piece of sheet-iron, 
 which will break off the dulled edges of the teeth, and leave a 
 new fibrous edge for the brass-work. Use bastard-cut files to 
 take off a quantity of metal of ordinary hardness ; second-cut, in 
 fitting, and also to file unusually hard metal ; smoothing, to fin- 
 ish in final adjustment or preparatory to applying emery-cloth ; 
 dead smooth, to finish very fine work ; float-file on lathe-work. 
 
 FiliES, To prevent scratching by. — To prevent files from pin- 
 ning, and hence from scratching, properly clean them, and then 
 chalk them well. 
 
 Files, To resharpen. — (1) Carefully clean them with hot water 
 and soda, then place them in connection with the positive pole of 
 a battery in a bath composed of 4 parts of sulphuric acid and 100 
 parts water. The negative pole is to be formed of a copper spi- 
 ral, surrounding the files but not touching them ; the coil termi- 
 nates in a wire reaching above the surface. Leave the files in 
 the bath ten minutes, then carefully wash them off, dry, and oil. 
 (2) Carefully clean the files in hot water and soda, and dip for 40 
 minutes in nitric acid of 41^ B. 
 
 Files, To select. — To choose a flat file, turn it edge upward, 
 and look along it, selecting those that have an even sweep from 
 end to end, and having no flat places or hollows. To choose a 
 half-round file, turn the edge upward, look along it, and select 
 that which has an even sweep, and no flat or hollow places on the 
 half-round side, even though it be hollow in the length of the 
 flat side. 
 
 Gravers, Grinding. — Gravers should be ground on the end 
 only, and not on the sides of the square, except when applied to 
 brass-work. 
 
 Half-Round Bits. — For drilling or boring liolesvery true and 
 parallel in the lathe, the half-round bit shown in the engraving 
 
30 
 
 MECHANICS. 
 
 is unsurpassed. The cutting edge. A, is made by backing off the 
 end, as denoted by the space between the lower end of the tool 
 and the dotted line, B, and performing its duty along the radius, 
 as denoted by the dotted line in the end and top views. It is only 
 necessary to start the half-round bit true, to insure its boring a 
 hole of any depth true, })arallel, and very smooth. To start it, 
 the face of the work should, if circumstances permit, be made 
 true ; this is not, however, positively necessary. A recess, true 
 and of the same diameter as the bit, should be turned in the 
 work, the bit then being placed in position, and the dead-centre 
 employed to feed it to its duty, which (if the end of the bit is 
 square, if a flat place be filed upon it, or any other method of 
 holding it sufficiently tight be employed) may be made as heavy 
 as the belt will drive. So simple, positive, and effective is the 
 operation of this bit that (beyond starting it true and using it at 
 a moderate cutting speed, with oil for wrought-iron and steel) no 
 further instructions need be given for its use. 
 
 KKi. 1.— IIALF-ROUNI) BITS. 
 
 In Fig. 2 is shown .\, a Imriiig I)ar ; 1? M is the sliding lii-ad ; 
 (.' C is tlie bore of the cylinder, and 1, 2, and ',i are tools in the 
 j)ositionH pliown. D I) 1) are projections in the bore of the cylin- 
 der, causing an exce.saive amount of duty to be ])laced ujion the 
 cutters, as soIM(•tiInc^s occurs wlien a cut of medium depili lias 
 been h-tiirti'd. Siidi a cut incniases on <mt'. side of the l)ore of tlie 
 work until, liecoming excessive, it causes the bar to tremhlt; and 
 
MECHANICS. 
 
 31 
 
 the cutters to chatter. In sucli a case, tool and position No. 1 
 would not be relieved of any duty, though it spring to a consider- 
 able degree ; because the bar would spring in the direction de- 
 noted by the dotted line and arrow E, while the spring of the 
 tool itself would be in the direction of the arrow, F. The ten- 
 dency of the spring of the bar is to force the tool deeper into 
 the cut instead of relieving it ; while the tendency of the spring 
 of the tool will scarcely afEect the depth of the cut. Tool and 
 position No. 3 would cause the bar to spring in the direction of 
 the dotted line and arrow G, and the tool itself to spring in the 
 direction of H, the spring of the bar being in a direction to in- 
 crease, and that of the tool to diminish, the cut. Tool and posi- 
 tion No. 3 would, however, place the spring of the bar in a direc- 
 
 FIG. 2— SPRING OF BORING TOOLS. 
 
 tion which would scarcely affect the depth of the cut, while the 
 spring of the tool itself would be in a direction to give decided 
 relief by springing away from its excessive duty. It must be 
 borne in mind that even a stout bar of medium length will spring 
 considerably from an ordinary roughing-out cut, though the lat- 
 ter be of an equal depth all round the bore, and from end to end 
 of the work. Position No. 3, in Fig. 2, then, is decidedly prefer- 
 able for the roughing-out cuts. In the finishing cuts, which 
 should be very light ones, neither the bar nor the tool is so 
 much affected by springing ; but even here position No. 3 main- 
 tains its superiority, because, the tool being pulled, it operates 
 somewhat as a scraper (though it may be as keen in shape as the 
 other tools), and hence it cuts more smoothly. It possesses, it is 
 true, the defect that the distance from the cutting point stands 
 further out from the holding-clamp, and the tool is hence more 
 apt to sprinof ; and in cases where the diameter of the sliding 
 head is muchless than that of the hole to be bored, this defect 
 may possess importance, and then position No. 2 may be prefer- 
 
32 MECHANICS. 
 
 able ; but it is an error to employ a bar of small diameter com- 
 pared to that of the work. 
 
 To obtain the very best and most rapid result, there should be 
 but little space between tiie sliding head and tbe bore of the 
 work ; the bar itself should be as stout as is practicable, leaving 
 the sliding head of sufficient strength ; and if the bar revolves in 
 journals, these should be of large diameter and with ample facili- 
 ties for taking up both the diametrical and end play of the boxes, 
 since the one steadies the bar while it is performing boring duty, 
 and the other while it is facing off end faces, as for cylinder-cover 
 joints. 
 
 Hammers, Chipping. — These should weigh about If lbs., and 
 have handles 15 inches long. 
 
 Metal having a very hard Skin, Tools used for. — When 
 the skin of the metal to be cut is unusually hard, as frequently oc- 
 curs in cast-iron, the shape of the cutting part of the boring-tool 
 must be such that its point will enter the cut first, so that it cuts 
 the inside and softer metal. The hard outside metal will then 
 break off with the shaving without requiring to be cut by the tool 
 edge, while the angle of tlie cut will keep the tool point into its 
 cut from the pressure required to break the shaving. A tool of 
 
 
 FIO. 1.— TOOL FOK HARD METAL. 
 
 this description is represented in the engraving, Fig. 1. a is the 
 point of the tool, and from a to B is the cutting edge ; the dotted 
 lines, c and D, represent the depth of the cut, c being the inside 
 skin of the metal, sup])osed to be hard. The angle at which the 
 cutting edge stands to the cut causes the pressure, due to tlie 
 bending and fracturing of the shaving, to be in the direction of e, 
 which keeps the tool jjoint into its cut ; while the resistance of 
 the tool point to this force, reacting upon the cut, from a to B, 
 causes the hard skin to break away. For use on wrought-iron, 
 however, th(! tool presented below will work to bett<!r advantage, 
 it being a side-tool. In the event of a side face Ix'ing very hard, 
 it possesses the advantage that the ])ointof the tool nuiy be made 
 to enter the cut first, and, cutting beneath the hard skin, fracture 
 it off without cutting it, the ])rcssur(' of the shaving on tlie tool 
 kecj)iiig th(! bittiTto its cut, as shown in Fig. 2. 
 
 /t is the ciittiii<r part f)f the tool ; B is a shaft with a collar on 
 it ; c is the side rut being taken off the collar, and D is the face, 
 supposed to be hard. The cut is luire sliown as being commenc- 
 ed from the largest diameter of thi' collar, and being fed inward 
 so that the point of the tool may cut well beneath tlie liard face, 
 ]), and HO that the pressure of the cut on tlie tool may keep it to 
 
MECHANICS. 
 
 33 
 
 its cut, as already explained ; but tlie tool will cut equally as ad- 
 vantageously if the cut is commenced at the smallest diameter of 
 the collar and fed outward, if the skin, D, is not unusually hard. 
 
 rop VIEW 
 
 FIG. 2. — TOOl, FOR HARD METAL. 
 
 Plane-Irons, Carpenters', To grind.— The 
 
 angle 
 
 of a plane- 
 iron should be about 25° 
 
 Plane Irons, Angle of, to face of planes.— For soft wood, 50° ; 
 for mahogany, 50° ; for soft wood for mouldings, 55° ; for hard 
 
 DEVICE FOR GRINDING PLANE-IRONS. 
 
 wood for mouldings, G0\ With this device, one man can both 
 turn the stone and grind the tool much more accurately than 
 by holding it in his hand. 
 
34 MECHANICS. 
 
 A is a piece of spring-steel, 8 inches long, bent at eacli end, 
 with thumbscrew. You grasp the holder with the left hand at 
 B, sticking the point, C, into a board or the wall, at sucli a dis- 
 tance from the stone as to bring the iron, D, in the right position 
 on the stone. By raising or lowering C, the bevel is regulated. 
 
 Raws .\nd Springs, Hardening. — The usual way of proceed- 
 ing is to heat the saws in long furnaces, and then to immerse 
 them horizontally and edgewise in a long trough containing the 
 composition ; two troughs are commonly used alternately. Part 
 of the composition is wiped off with a piece of leather, when the 
 articles are removed from the trough ; they are then heated one 
 by one over a clear coke fire until the grease inflames ; this is 
 called " blazing ofE." A greatly recommended composition 
 consists of 2 lbs. of suet and J lb. of beeswax to every 
 gallon of whale oil ; these are boiled together, and will 
 serve for thin articles and most kinds of steel. The addi- 
 tion of black resin, to the extent of about 1 lb. to the 
 gallon, makes it serve for thicker pieces, and for those it 
 ref usetl to harden before ; but the resin should be added with 
 judgment, or the articles will become too liard and brittle. The 
 composition is useless when it has been constantly employed for 
 about a month ; the period depends, however, on the extent to 
 which it is used, and the trough should be thoroughly cleaned 
 out before the new mixture is placed in it. The following 
 recipe is commended : 20 galls, spermaceti-oil, 20 lbs. 
 melted and strained beef suet, 1 gall, neats'-foot oil, 1 lb. 
 pitch, 8 lbs. black resin. These last two articles must be 
 previously melted together, and then added to the other in- 
 gredients ; the whole must then be heated in a proper iron 
 vessel, with a close cover fitted to it, until the moisture is 
 entirely evaporated, and the composition will take fire on a flam- 
 ing body being ])resented to its surface ; the flame must be in- 
 stantly extinguished again by putting on the cover of the vessel. 
 When the saws are wanted to be rather hard, but little of the 
 grease is burned off ; when milder, a largi; portion ; and for a 
 spring temper, the whole is allowed to burn away. When the 
 work is thick, or irregularb' thick and thin, as in some springs, 
 a second and third dose is burned oil', to insure equality of 
 temper at all points alike. Gun-lock springs are sometimes lite- 
 rally fried in oil for a considerable time over a fire in an iron tray. 
 The thick parts are then sure to be sufficiently reduced, and tin; 
 thin parts do not become the more softened from the continuance 
 of the, blazing heat. Si)rings and saws ap])ear to lose their 
 elasticity after hardening and tempering, from tlie re<luction ami 
 friction they undergo in grinding and ])()lishing. Toward the 
 conclusion of the manufacture, the elasticity of tln^ saw is re- 
 Ktor»!d princii)ally by hammering, and partly by lu-ating over a 
 clear coke fire, to a straw-color ; the tint is removed by very 
 diluted muriatic aciid ; after wliicli the saws aro well washed in 
 plain wat(,r and liried. 
 
 Saws, Band, To solder. — Scarf tlio end of the saw to a taper for 
 a distance of two liiu! or on<! coarse tooth, fitting thi; edgtis of tlio 
 scurf very true and level. Clean the joint with acid, and clamp the 
 
MECHANICS. 35 
 
 saw ends together with a suitable frame or clamp. Heat the 
 joint with a pair of red-hot tongs, and place a small strip of 
 jeweler's silver solder upon the joint ; press it upon the same 
 with the red-hot tongs. As soon as the solder has properly run 
 or flowed, remove the tongs and cool the joint with water, to re- 
 store as far as possible the temper of the saw. Then hie the 
 joint to an even thickness and level with the rest of the saw, 
 using a wire gauge as a template. 
 Saws, Circular, Speeds for : 
 
 Diameter of 
 
 
 
 
 saw, 
 
 Revolutions per minute for 
 
 Eevolutions per minute for 
 
 inches. 
 
 English or thin 
 
 saws. 
 
 American or thick saws. 
 
 36 
 
 1000 
 
 
 1500 
 
 30 
 
 1200 
 
 
 1800 
 
 25 
 
 1400 
 
 
 2100 
 
 20 
 
 1500 
 
 
 2400 
 
 15 
 
 1800 
 
 
 2700 
 
 10 
 
 2900 
 
 
 3000 
 
 Circular saws of over 40 or 50 inches in diameter are, or should 
 be, hammered to run at a certain speed. This is more important 
 when the speed is as high as from 700 or 900 revolutions per 
 minute. If a saw is so hammered as to do good work at 300 or 
 400 revolutions per minute, it will not do as good work at 900, for 
 the reason that the high speed expands the outside or rim, causing 
 it to dish, or " flop around," as sawyers sometimes express it. In 
 such cases, and when it is inconvenient to reduce the speed, it 
 will be necessary to guide the saw out of the log so as to cause 
 the central part to rub against the log enough to heat it slightly, 
 thus expanding the portion that needs hammering. An expert 
 sawyer can in this way manage indifferently well, though at an 
 expense of considerably more power. A large saw, to run well 
 at high speed, should be hammered in the centre part until it is 
 slightly dishing, or, as it is variously expressed, "loose at the 
 eye," or " rim-bound." It may be loose at the eye when it is the 
 reverse of rim-bound, namely, too open at the rim, which is the 
 most frequent trouble with such saws. They all become so 
 eventually from use, and should then be rehammered. 
 
 Saws, Hints concerning. — A saw just large enough to cut 
 through a board will require less power than a saw larger, the 
 number of teeth, speed, and thickness being equal in each. The 
 more teeth, the more power, provided the thickness, speed, and 
 feed are equal. There is, however, a limit, or a point where a 
 few teeth will not answer the place of a larger number. The 
 thinner the saw, the more teeth will be required to carry an equal 
 amount of feed to each revolution of the saw, but always at the 
 expense of power. When bench-saws are used, and the sawing 
 is done by a gauge, the lumber is often inclined to clatter and to 
 raise up the back of the saw, when pushed hard. The reason is 
 that the back half of the saw, having an upward motion, has a 
 tendency to lift and raise the piece being sawn, especially when 
 it springs and pinches on the saw, or crowds between the saw and 
 the gauge ; while the cut at the front of the saw has the opposite 
 tendency of holding that part of the piece down. The hook or 
 
36 
 
 MECHANICS. 
 
 pitch of a saw-tooth should be on a line from J to ^ the diame- 
 ter of the saw : a } pitch is mostly used for hard, and a ,^- for 
 softer timber. For very fine-toothed saws designed for heavy 
 work, such as sawing shingles, etc., even from suit wood, ^ pitch 
 is best. 
 
 SAW-TEETH. 
 
 Saw-Teetr, Shapes of. — No. 1 is a good-shaped tooth for very 
 soft wood, the wide bevel being the front of the tooth. The 
 point would be liable to break or bend in very hard wood or in 
 knots. No. 2 will stand to saw the hardest timber or knots, but 
 will not cut as easily as No. 1. No. 3 is a form of point general- 
 ly used for promiscuous sawing of both liard and soft wood. The 
 set must be wide enough to clear the plate. After filing your 
 saw, place it on a level board and pass a whetstone over tlie side 
 of the teeth until all the wire-edge is off them. This will make 
 the saw cut true and smooth, and it will remain sliarj) longer. 
 The saw must be set true with a saw-set. 
 
 Scrapers, To make. — Old files which have never been recut 
 make excellent scrapers. 
 
 Scrapers, Use of. — All work should be fitted as nearly true as 
 possible before being scrajied with the fiat scraper, which is in- 
 tended for fl;it surfaces only. For hollow work, curves, etc., the 
 half-round scraper is the best, the three-cornered being the least 
 efficient of all scrapers. 
 
 Taps and Reamers, Finishing. — The forgings are got out in 
 the usual way, left to anneal, centred, and turned just sufficient to 
 remove the scale. Then anneal again, and tuiii dt)wn to within 
 ^V iiK'h, or less, of finisliing size. Anni-al once more, and finish 
 in the lathe. If not sprung in turning, the taj) or reamer will 
 come out all riglit when hardened. This hiis been tested euccess- 
 f'uliy with taps from i inch in diameter and IJ iuclies long up to 
 those of 1 inch in diameter and 2 feet long. 
 
 Taps, Temixsring and hardening. — 'i'o harden a tap, heat to a 
 cherry-red, in a clear and not a blazing lire, or, what is better, 
 heat in cliarcoal, liolding tlie tap by the square end ; dip it 
 endwisc! in the water, immersing the whole of the threaded ])nrt 
 first, and holding it still niitil the phiin jiiirt is of a V(!ry low red ; 
 slowly iinmer.se the renininder, hnlding it still, when fully im- 
 mersed, until it is (piite cold. 'I'lien brigliten the fiutes, and tem- 
 ))er as follows : lleat a ])iece of tul)i! (with a bore about twice tlie 
 <liiimeter and a length one lialf that of the tap) to a bright red 
 lieat, lake it Croni the fire, set it iiji vertically, iind hold the taji in 
 tin- centre of thc' tiilie, with the iijaiii puit of the i;i|i in the tuhi; 
 
MECHANICS. 
 
 31 
 
 and the thread part projecting. Revolve it in this position suffi- 
 cient time to heat the plain end about as warm as the hand can 
 bear it ; then keep revolving tlie tap and moving it endwise back 
 and forth through the tube until the thread will color to a deep 
 brown and the shank to a brown purple. If any unevenness ap- 
 pears in the color, hold the parts having the lighter color a little 
 longer in the tube, or cool the part coloring too deeply by apply- 
 ing a little oil to it. Perform the whole process slowly, taking 
 the tap from the tube to retard it, if necessary. 
 
 Taps, Tempering. — The squares of taps should be tempered to 
 a blue. 
 
 Taps, To temper, without springing. — Forge the tap with a 
 little more thau the usual allowance, being careful not to heat 
 too hot, nor to hammer too cold. After the tap is forged, heat it 
 and hold it on one end upon the anvil. If a large one, hit it with 
 the sledge ; if a small one, the hammer will do. During this ope- 
 ration, the tap will give way on its weakest side and become bent. 
 Do not attempt to straighten it. On finishing and hardening the 
 tap, it will become perfectly straight. 
 
 Tools, Spring of. — To obviate the spring of tools which must, 
 of necessity, be held out a long way from the tool-post, the ful- 
 crum off which the tool springs must be adjusted so as not to stand 
 in advance of the cutting edge of the tool. In the engraving, a 
 represents the fulcrum off wliich the tool takes its spring ; B is 
 the work to be cut ; and the dotted line, C, is the line in which 
 
 SFUING-TOOL. 
 
 c^ 
 
 the point of the tool would spring (being in the direction denoted 
 by the arrow), which is not in this case into' the cut, but rather 
 
38 MECHANICS. 
 
 away from u, in consequence of the point of the tool standing 
 back from a line perpendicular to the line of the back part of the 
 tool, as sbovvu by the dotted line, D. 
 
 MECHANICAL SHOP-WRIXKLES AND 
 DIRECTIONS. 
 
 ANNEAI.ING Iron and Steel. — Save the scales from the forge 
 (oxide of iron) for this purpose. 
 
 Anvils, Tempering. — This can be done by simply heating the 
 anvil and immersing it in a tank of cold water to a depth of two 
 or three inches. Play a stream of water from a hose on the face. 
 
 Axles, Value of hollow.— An old apprentice of Sir William 
 Fairbairn writes : " For several years it has cost me five dollars 
 a week to keep the bolts on my trip or cushioned hammer-heads 
 in repair, and, finding it to wear on my patience, I tried all kinds 
 of iron, but to no use ; break they would. I finally bored a hole, 
 one third the diameter of the bolts (1^ in.), and put a | in. 
 hole down, some way below the thread, which formed a tube. I 
 have now run them for three months, and they show no signs of 
 giving out. The wrench used would break the other bolts easily ; 
 but it can not do so with these. My work on spindles requires 
 the dies to snap together about nine times in ten, which tells very 
 severely on the bolts." 
 
 Bkxding Coi'I'EH Pipes. — Fill thorn with resin or lead, which 
 will prevent them from buckling in the bends. 
 
 Bolts and Studs, Standing.— When these are placed in posi- 
 tions liable to corrode them, they should have the standing ends 
 I in. larger than the end receiving the nut, and the plain part 
 should be square. By this means a wrench may be apj)ned to 
 extract them when necessary. The stud, also, is not so likely to 
 break off in consecjucncc; of weakness at the junction of the thread 
 and the plain jjart, where the groove to relieve the terminati(m of 
 the thread is cut. 
 
 Bolts oh Studs, Standing, To unscrew.— Studs that have be- 
 come so corroded in their liolcs that they are liabh; to break off. 
 should be well warmed by a red-hot washer ; becausii the strength 
 of the stud increases ])y being hi-ated up to about 400" Fahr., and 
 therefore studs which readily twist off when cold will unscrew 
 when heated to about that teniperatun-. Nuts upon standing 
 bolls of studs, in the smoke-boxes of locomotives, or in similar 
 l)ositionH, whidi have become so corroded as to endanger twisting 
 off, should b(! cut through on one side with a cape or cross-cut 
 cliisel, thus saving tlie stud at the expense of the nut. The split 
 must be cut from the end face of the nut to the bedding face. 
 
 BUAHSKS, Bedding down. — In bedding down brasses or journal- 
 lK)xes of any description, tlie following i)lan should b<- einploycfd 
 to gauge liow much requires to be chipped or filed away from any 
 
MECHANICS. 39 
 
 part or parts of the bed of the brass to enable it to bed to its seat 
 all over : Take ordinary red marking (which should be composed 
 of Venetian-red and common oil, mixed to the consistence of a 
 thick paint), and paint over the vrhole bed into which brass is to 
 be fitted. Then take some putty (mixed stiffly), and rolling it 
 into pellets about the size of a large pea, place them here and 
 there upon the painted surface. Then drive the brass home, and 
 drive it out again, when it will be found that the thickness to 
 which the pellets have been smashed by the bottom of the brass 
 registers to the greatest possible exactitude how near the bottom, 
 of the brass comes to the bed of the bottom of the bearing, indi- 
 cating precisely the amount to be chipped and filed ofE the bottom 
 of the brass to bed it. It is better, however, to be careful not to 
 take too much off at first, and to repeat the process with the pel- 
 lets. It must be borne in mind carefully to replace the old pel- 
 lets with new ones at each trial, otherwise you will be misled. 
 The object of painting the bottom of the box with red marking, 
 before placing the pellets, is to cause the latter to stick to the 
 box and not to the brass, and to prevent them from falling out 
 when the box is turned upside down to drive the brass out. This 
 is the only practical method of ascertaining how much to take off 
 a brass to' bed it, and will be found an easily applied and almost 
 invaluable assistance. 
 
 Brasses, Fitting. — In doing this, a piece of wood must be 
 used to hammer on in driving them in and out, since driving 
 them with the bare hammer, a piece of metal, or a mandril, 
 stretches the skin and enlarges the diameter across the bore ; 
 then when the brasses are bored and the stretched skin is con- 
 sequently removed, the brass resumes its original shape, and 
 hence becomes loose in the strap or box. In fitting brasses to 
 their places, leave them a little too tight, since all brasses con- 
 tract a little across the bore in consequence of the process of 
 boring. This rule applies also to journal-boxes of cast-iron or 
 any other metal. 
 
 Brasses, Setting. — In setting brasses or any other journal- 
 boxes to be bored, place a piece of sheet-tin between the joint of 
 the brasses, and bore the brasses or boxes the thickness of the 
 tin too large, which thickness may be gauged by placing a small 
 piece of the same tin under the leg of the inside calipers when 
 trying the bore. The reason for this is that practice demon- 
 strates it to be an invariable rule that a half-circle or half-hole, 
 whether in a movable brass or in a solid box, will never fit 
 down upon its journal, but will bind upon the edges across the 
 diameter, and must therefore be scraped or filed on the sides to 
 let the crown down. This defect is obviated by the employment 
 of the sheet-tin as described, which will save three fourths of 
 the time usually required to fit such work to a good bearing. 
 This plan is highly advantageous in boring eccentric straps and 
 large brasses ; and the larger the size, the thicker the tin may be. 
 
 Brass Turnings and Filings, To melt, with little waste. — 
 Compress in a crucible until it is full, then cover, and lute the 
 top with pipe or fire-clay. 
 
40 MECHAXICS. 
 
 Burr Stones. Filling holes in. — Use melted alum mixed with 
 burr-stone pulverized to the size of grains of saud. 
 
 Burrs, To prevent heating, — Dress from centre to circum- 
 ference, leaving no bosom. Draw a line across the centre, each 
 way, dividing a four-foot burr into 16 squares or divisions, and 
 other sizes, more or less, in the same proportion, with all straight 
 furrows. Let the draft be ^ the diameter of the rock. Lay off 
 the lands and furrows J inch each, observing to dress smooth. 
 Sink the furrow at the eye i inch deep for corn, and run out to 
 tV at the periphery ; for wlieat, 1% at the eye, and ^ at the peri- 
 phery. When thus finished, crack the lands in straight lines, 
 square with the draft of cross-lines, so as to make the lands face 
 in the runner and bed direct. This will never heat. 
 
 Carpenter's Bench, To make a. — Take three pieces of 2 x 5 
 in. stuff, 3 feet long, for supports for top. Take two 12 in. 
 boards, 13 feet long and 1 in. thick, for sides ; nail the side- 
 boards firmly on to the ends of the 3x5 cross-pieces, and j)ut ou 
 a top of suitable material, and you liave a bench without legs. 
 Then take four pieces of 2x5in. stuff" of the desired height for 
 the legs, and frame a piece 1x3 inches across each pair of legs, 
 6 inches from the bottom of tlie leg, putting the legs at the pro- 
 per distance apart for width of bench. Cut a fork or slit in the 
 toji end of each leg, s.o as to straddle the crOSs-piece at the ends ; 
 put a 3^ X f in. bolt through each leg and the side-board, and 
 you have a good solid bench, that can be taken down in five 
 minutes by simply removing the four bolts. It can also be taken 
 through any door or window, or down or up stairs, or to any 
 place required. 
 
 Castings, Brass. — These shrink I inch to the foot in cooling. 
 
 Castings, Copper, To prevent air-holes in. — Cast in green sand, 
 and not in dried moulds, using lA lbs. zinc as a flue, as pure 
 copper will not run sufficiently freely to prevent honeycombing. 
 
 Castings, Copper. — These shrink i inch to the foot in cooling 
 in the moulds, and also shrink (as do all other castings) most 
 where there is the greatest substance of metal. 
 
 Castings, Holes in, To prevent. — In casting iron on iron or 
 steel spindles, the moulds are cast endwise, letting the cast 
 metal covering the spindle be an inch longer on the uppermost 
 side than is necessary when the job is finished ; tlius the air- 
 holes, if any, will form in the extra inch of lengtli, aud may be 
 cut off in tlu! lathe. 
 
 Castings, Ikon. — These shrink ^ inch to the foot in cooling in 
 the moulds. 
 
 C.\HTiNGS, Slirinkage of. — Slirinkagn sideways and endwise, on 
 castings of 3 inches and less size, is conipensattHl for by the 
 shake in the sand given by tlie moulder to the pattern in order 
 to extract it from tlio mould. 
 
 Cahtin<is, Small. — In very small castings re(|uiring to be of 
 correct size, allowance should be made in tlie pattern for tlie 
 shako of tlie ])attern in tlu; sand, thus : A i)attern of an inch cube 
 will refjuire to be made ^.^ inch less endwise and sideways, and 
 
MECHANICS. 
 
 41 
 
 tlie usual allowance above an inch must be made on the top face 
 of the pattern, which should have " top" marked on it ; thus the 
 shake endwise and sideways given to the pattern, in order to ex- 
 tract it without lifting the sand, will be allowed for in the size 
 of the pattern. The effect of this shake in the sand is appreci- 
 able in patterns tip to about four inches diameter. It is a com- 
 mon practice to cool brass castings in order to loosen or remove 
 the sand from the surfaces. The effect is to place conflicting 
 strains and tensions tipon tlie whole skin of the metal, which will 
 alter its shape when the outer skin of such faces is removed ; so 
 that, supposing the casting to be a cube, no one face will be 
 either true of itself or with the others when it has been planed, 
 no matter how true the surfacing may have been performed. 
 
 Castings, Smooth. — A means highly recommended for obtain- 
 ing very smooth castings, is mixing with the green foundry sand 
 forming the mould about 2T) part of tar, a mixture which is em- 
 ployed without the addition of any other substance. 
 
 Castings, To estimate the weight of. — 
 
 A pattern weighing 1 lb., and made 
 of 
 
 Mahogany 
 
 (St. Domingo) 
 
 Maple 
 
 Beech 
 
 Cedar 
 
 Yellow Pine 
 
 White Pine 
 
 Will weisrli when cast in 
 
 Cast 
 Iron. 
 
 Zinc. 
 
 Copper. 
 
 Yellow 
 Brass. 
 
 8 
 
 8 
 
 10 
 
 9.8 
 
 10 
 
 9.5 
 
 12 
 
 11.5 
 
 10 
 
 9.8 
 
 12.5 
 
 12 
 
 11 
 
 11 
 
 14 
 
 13.4 
 
 11.5 
 
 11.4 
 
 14.5 
 
 14 
 
 13 
 
 12.6 
 
 16 
 
 15.5 
 
 14 
 
 14.5 
 
 18 
 
 17.5 
 
 Gun 
 
 Metal. 
 
 10 
 
 12 
 
 12.4 
 
 13.8 
 
 14.5 
 
 16 
 
 17.8 
 
 Example : The pattern of a wheel made of cedar weighs 8 lbs, 
 how much will a casting of iron weigh 1 8 lbs. weight of pat- 
 tern multiplied by 11.5, which is the multiplier for iron set oppo- 
 site cedar, equals 92.0 weight of casting. 
 
 Chuck-Cement, Removing, from lathe-work. — Warm the ob- 
 ject over a spirit-lamp, and tap lightly with a stiff brush ; the 
 wax will adhere to the latter. If in a hurry, a few seconds' boil- 
 ing in alcohol will remove the remainder of the wax. 
 
 Chuck-Lathe, An electric. — In order to obviate the inconve- 
 nience and loss of time involved in the ordinary mode of fixing 
 upon a lathe-chuck certain special kinds of work, such as thin 
 steel disks or small circular-saws, the chuck may be converted 
 into a temporary magnet, so that the articles, when simply placed 
 on the face of the chuck, are held there by the attraction of the 
 magnet ; and, when finished, can be readily detached by merely 
 breaking the electric ctirrent and demagnetizing the chuck. The 
 face-plate of the magnetic chuck is composed of a central core of 
 soft iron, surrounded by an iron tube, the two being kept apart 
 by an intermediate brass ring ; and the tube and core are each 
 
42 MECHANICS. 
 
 surrounded by a coil of insulated copper wire, the ends of which 
 are connected by two brass contact-rings that encircle the case 
 containing the entire electro-magnet thus formed. These rings 
 are grooved, and receive the ends of a pair of metal springs con- 
 nected with the terminal wires of a battery, whereby the chuck is 
 converted into an electro-magnet capable of holding firmly on its 
 face the article to be turned or ground. For holding articles of 
 larger diameter, it is found more convenient to use an ordinary 
 face-plate, simply divided into halves by a thin brass strip across 
 the centre ; a horseshoe-magnet, consisting of a bent bar of soft 
 iron, with a coil of copper wire around each leg, is fixed behind 
 the face-plate, each half of which is thus converted into one of 
 the poles of the magnet. The whole is inclosed in a cylindrical 
 brass casing, and two brass contact-rings, fixed around this casing, 
 are insulated by a ring of ebonite, and are connected with the two 
 terminal wires of the magnet-coils. A similar arrangement is 
 also adapted for holding work upon the bed of a planing or drill- 
 ing machine, in which case the brass contact-rings may be dis- 
 pensed with, and any desired number of pairs of the electro-mag- 
 netic face-plates are combined so as to form an extended surface 
 large enough to carry large pieces of work. For exciting the 
 electro-magnet, any ordinary battery that will produce a continu- 
 ous current of electricity can be used. 
 
 Cocks, To grind plugs in. — The best material for this purpose 
 is the red, well-burnt sand from the core of a brass casting, the 
 sand being sifted, before using, through fine wire gauze. It will 
 cut more truly and smoothly than any other material, and should 
 be used with water, and not oil. After the cock is sufficiently 
 ground, wash it and the barrel with clean water ; and after wip- 
 ing them comparatively but not quite dry, revolve the plug 
 backward and forward in its place under a slight pressure, and 
 the surface will assume a rich Ijrown color, showing very dis- 
 tinctly the precise nature of the fit, and leaving a smooth sur- 
 face, free from grit and not liable to either jam or abrade. 
 Valves may be ground to their seats in a similar manner. 
 
 Cones in Holes, Fitting. — Rub the cone with either red mark- 
 ing or else chalk, giving it in either case a very thin coat. A 
 narrow strip of marking, running from end of the cone, will do. 
 Put tlie cone into its place, press it forward and revolve it back 
 and forth, and the marks will show wlu-rc it binds. 
 
 CoNNECTiNG-KODS, Fitting. — When the cross-head and crank- 
 pin are in their places upon the engine, fitting may b(^ done 
 as follows : Connect the cro.ss-head end of the rod in its place 
 upon the cross-head journal, keeping the other end clear of the 
 crank-pin; put the l)rass('s and keys in their idaces in the rod 
 end, then lower tlir- crank-jiin end ujion tin- crank-pin journal, 
 which will sliow wlietlier tlie cross head journal leads true ; if 
 it does not, move the crank-i)in end of the rod Ijack and forth, 
 exerting a side j)rcsHure on it in the direction in wliich it wants 
 to go, so us to ))lainlv mark where the connecting-rod brasses of 
 the cross-head end rei|uire easing; and after th(! crossliead end 
 is adjusted, put tlie crank-pin of the rod upon its place upon the 
 
MECHANICS. 43 
 
 crank-pin, keeping the cross-head end clear of the cross-head ; 
 put the brasses, keys, etc., in their places, and proceed as before. 
 Red marking should be rubbed on both the crauk-pin and cross- 
 head journals, so as to mark the brasses plainly. A halt-round 
 file and half-round scraper should be used to adjust and ease 
 the brasses. 
 
 CONNECTING-EOD STRAPS, To close the jaws of. — If the jaws 
 are too wide at the points, rest the stra^) upon the two ends, and 
 (with a round pene-hammer) lightly hammer the outside of the 
 crown of the strap all over, taking care to hammer it evenly, so 
 as not to leave any deep hammer-marks. 
 
 Connecting-rod Straps. — To open the jaws of a connecting- 
 rod strap, hammer the inside face of the crown of the strap lightly 
 and evenly all over with a round pene-hammer. To bring back to 
 its original shape a strap that has been opened or closed in its 
 width between the jaws, by being pened with a hammer, remove 
 by filing ^^^ inch in depth of the surface that has been hammered, 
 or heat the part hammered to a low red heat. 
 
 Connecting-rod Straps, Refitting, to rods.— Place the gib and 
 key in the strap to prevent it from warping, and heat the crown end 
 of the strap to a bright red ; on taking it from the fire, remove 
 the scale by lightly filing with a coarse file ; then plunge the 
 strap to nearly half the thickness of the crown in water, and 
 after holding it there for about ten seconds, slowly immerse the 
 remainder of the strap in the water, and withdraw when quite 
 cold. It will be found to have closed along its whole length, al- 
 though mostly at the points. 
 
 Copper or Brass, To soften. — Heat to a low red heat, and 
 plunge in salt water. 
 
 Copper, To harden. — Copper may be slightly hardened by 
 closing the grain. This can be done by lightly hammering its 
 surface with a round pene-hammer. 
 
 CoRtrNDUM-WHEELS, To true. — The wheel being adjusted in 
 the lathe, revolve it very fast, holding a piece of corundum-stone 
 against the uneven or wabbling surface. In a short time, the 
 piece will melt and tinite itself to the wheel, so as to make the 
 latter perfectly true. 
 
 Cotton- Waste, To clean greasy. — Boil it in a strong solution 
 of common soda in water, and save the resultant soapy liquid to 
 keep your drills and reamers wet when boring iron. 
 
 Crank-pins, Riveting. — In riveting over the end of a crank- 
 pin, apply the hammer most around the outer circumference and 
 least toward the centre ; this will prevent the riveted end from 
 splitting. 
 
 Emery, for grinding purposes. To prepare fine. — When no 
 fine emery is at hand, place coarse emery upon an iron block or 
 plate, and hammer it well with the face end of the hammer ; after 
 which, grind it by abrasion with the hammer face. 
 
 Emery- Wheels, Speed of. — A G-inch emery-wheel should 
 
44 MECHANICS. 
 
 make about 3400 revolutions per minute ; an S-incli, 1800 ; a 12- 
 incU, 1200. 
 
 Engine-room Chairs. — Good chairs for engine-roona or factory 
 use are easily made of light gas-pipe. 
 
 Grease, To clean, from bolts. — Moisten in benzine, roll in saw- 
 dust, and brush afterward. 
 
 Grindstones, Care of. — These should never be left in the sun- 
 lijrht, or with one side standing in water, since heat evaporates the 
 water in the stone, leaving it harsh and hard, wliile saturation 
 softens it. The grindstone is a self-sharpening tool ; and after 
 being turned in one direction for some time (if a hard stone), 
 the motion should be reversed. Sand of the right grit applied 
 occasionally to a hard stone will improve it. 
 
 Grindstones, Selecting. — When you get a stone that suits 
 your purpose, send a sample to the dealer to select by; a half- 
 ounce sample is enough, and can be sent by mail. 
 
 Grindstone-Si'indles. — Common grindstone-spindles, with a 
 crank at one end, are open to the objection that the stone will 
 never keep round, because every person is inclined, more or less, 
 to follow the motion of his foot with his liand, which causes the 
 pressure on the stone to be unequal. The harder pressure is al- 
 ways applied to the very same part of the stone, and will soon 
 make it uneven, so that it is impossible to grind a tool true. To 
 avoid this, put in place of the crank a small cog-wheel to the 
 spindle, say with twelve cogs ; have another short spindle, with 
 a crank and a cog-wheel of tliirteen cogs, to work into the former. 
 The stone will make about 0.07 of a revolution more than tlie 
 crank, and tlie harder pressure of the tool on the stone will change 
 to anotlier place at every turn ; and the stone will keep perfectly 
 round if it is a good one. 
 
 Grindstone, To true a carpenter's. — Use a J-inch bar of iron, 
 or a gas-pipe, for a turning tool, held below the centre of the 
 stone. 
 
 Hardening, To prevent cracking of metals wliile. — Heat the 
 water as hot a.s bearable to the liands, dip tlie metal endwise, and 
 immerse with the thickest part of the metal downward. When 
 fully immersed, hold the metal still until it is quite cold. 
 
 Ikon, Cast, To harden. — Inlj gallons of clean water, mix \ i)int 
 oil of vitriol and 2 ozs. saltpetre. Heat the iron to a cherry-red, 
 and dip as usual. 
 
 Tuo.\, C.vst, Mixture for cast-iron cylinders, reriuiring to bo 
 liard. — 'I'wenly pounds charcoal j>ig So. .'j, 40 lbs. Scotch pig, JJOO 
 lbs. scrap-iron. 
 
 TuoN, Cast, Mixture for strong and clos(i-grained cast-iron for 
 steam cylinilers, (Me. — Eighty pounds charcoal pig No. T), 100 lbs. 
 Scotcli i)ig, and 100 lbs. 8<Tap-iron. 
 
 Ikon, M.M-i.icaiw.k. Cast, To harden. — Mix eciual parts of com- 
 mon j)otash, saltpeln-, and Huli)hate of zinc, and use as directed 
 for ]>ru8Hiut<! of potasli. 
 
MECHANICS. 45 
 
 Iron Plate, To straigliten a curved. — Hammer it liglitly with 
 a round pene-liammer ou the hollow side. 
 
 Iron Plates with true, flat surfaces. — To make a true surface- 
 plate, it is necessary to plane up three plates, which we will 
 term A, B, and C. First fit the faces of A and B together as 
 nearly as possible with a smooth file (using a hardly perceptible 
 coating of Venetian-red and common oil applied to A, to show by 
 the marks where the faces touch). Then file C to fit A. Then 
 try C with B ; and if they mark all over the faces, they are true, 
 and the surfaces may be finished by the scraper, trying them re- 
 peatedly as above. If, however, C and B should be found to fit 
 on the edges only, it would demonstrate that A and B, though 
 fitting, are not fiat surfaces ; but that A is hollow and B round- 
 ing. Having corrected these defects as nearly as possible, apply 
 B to C, again repeating the connecting process until all three sur- 
 faces, applied interchangeably, mark evenly all over, when the 
 surface of each will be practically true. It must, however, be 
 borne in mind that, after rubbing the surfaces together to test 
 them, tlie middle of each plate will (from having received the 
 most abrasion) show the marks the plainest, so that the plates 
 will be more nearly true if the marks show a little the plainest 
 at and near their edges, and less plain toward the centres. The 
 back of each plate should be planed off, care being taken that it 
 rests evenly upon the bench, so that neither plate shall deflect 
 from its own weight, as it would do if its weight were not sup- 
 ported evenly upon the face resting upon the bench. The scrap- 
 er should be used dry upon cast-iron, and kept moistened with 
 water for steel, wrought-iron, and brass. 
 
 Iron, Eed-hot, To mark measures on.— Blacksmiths fre- 
 quently measure a piece of iron, and put chalk-marks where they 
 desire to cut it. The iron may then be placed in the fire and 
 heated to a bright red without effacing the marks. 
 
 Iron, To remove hard skin from. — Hard skin on iron is due to 
 heat and friction, and may be removed by heating to a dull red, 
 filing the surface, and putting the iron to cool in lime or ashes. 
 
 Iron, Wrought, Contraction of. — Wrought-iron may be made 
 to contract to a slight extent l)y heating it to a low red heat, and 
 quenching it in water. The first operation only, however, is ef- 
 fective. This plan is used to shorten eccentric rods, etc., to avoid 
 getting them out of true by upsetting them with blacksmiths' 
 tools. 
 
 Iron, Wrought, To close holes in. — If a washer or other 
 piece of wrought-iron is a trifle too large, fill the hole and part of 
 the outside faces with fire-clay ; heat the iron to a bright red, and 
 plunge it in cold water. The contraction of the circumferential 
 iron will squeeze the metal round the hole (which has been pre- 
 vented from cooling so rapidly by the clay) inward, diminishing 
 the size of the hole. To refit a bolt to a hole in which it has 
 worn a trifle loose, case-harden it by the prussiate of potash pro- 
 cess, which will increase the diameter of the bolt. If it fits into 
 a hole of wrought-iron or steel, that too may be case-hardened, 
 which will diminish its size, and thus refit it "to the bolt. 
 
4fi MECHANICS. 
 
 Joints, Rubber. — In making a rubber joint, take a piece of 
 chalk and rub it on the side of the rubber and tiange where the 
 joint is to open ; and wlien required, they will come apart easily, 
 and not break the rubber, although the latter may be burnt and 
 hard. Repeat the chalking before screwing up, and you will 
 have as good a joint as ever, and the rubber can be used a great 
 number of times. 
 
 Keys, Driving. — Drive the key into the keyway to mark where 
 it binds. The keyway should be oiled first, especially if the 
 metal is cast-iron ; otherwise the surfaces are liable to seize a 
 cut, making it very difficult to drive the keys out, and cutting 
 ragged grooves in both the keyway and the key. The same 
 rule applies to crank-pins and all similar work. 
 
 Keys, To make. — These should be made to fit the key ways at a . 
 good fit on the sides without being tight, the locking being per- 
 formed by the taper of the top and bottom, the amount of which 
 should be about i inch per foot of length. 
 
 Keywat and Slots, To ease, Avhen hardened. — Take a strip of 
 copper and use it as a file, applying oil and fine emery upon the 
 surface of the work. 
 
 Lathe, Setting work on the face-plate of a. — Let the work be 
 set out and first lightly prick-punched ; then clamp to place light- 
 ly as near as possible, but never set the " dead-centre" against 
 the work, for that will not bring it true ; now with a scratchawl 
 or sharp-pointed centre, with the point resting in the prick-mark, 
 and the other end held against or on the dead centre, revolve the 
 work. If the point marked for the centre of the hole is out of 
 true, the scratch-awl, or whatever rests in the point, will vibrate. 
 Put into the lathe-rest a tool, without fastening it, and push it 
 up to the scratch as the work is revolved, and the extent of the 
 vibration can be seen. Tlie work can be driven as thus indicat- 
 ed when there is no vibration of the scratch or centre, the work 
 is perfectly set, and may be securely fastened. 
 
 Liners, Thickness of. — To ascertain the proper thickness of a 
 liner or strip necessary to go between a pair of brasses so that 
 (wiien the faces do not meet) the liner may be placed between 
 theni and the brasses, when bolfeil up tight, without jamming 
 the journal, jilace a ])iece of lead winHM't ween the brasses, and 
 then screw thi^ caj) down tight, and the lead wir(> will comjiress, 
 denoting the necessary thickness of liner. The latter should be 
 made a sliade thicker than the distance the wire was compress- 
 ed, so that the brasses may fit witliDut binding the; journal. 
 
 Links, To clos(' a (luadrant or link that has sprung or opened in 
 liardening. — C'lamp it with bolts and plates, placing the die in tlie 
 slot to Hup|)ort any ])art which does not require to be closed. 2'(9 
 open Old xlol of (I (piiidrant or link tlutl hus closed in being hardened : 
 Take two kej-s having an e<jiiul amount of taper upon tliein, and 
 l>lace th(!ni togeiiii-r so tlmt their outside edges are j>aral]ei. In- 
 H<!rt ilieiM in tliiit pait of tli(^ slot which reipiires to be o])ene(l, 
 •and Iioldiiig a liainnier auainst tin; head f)f one key <n\ one side 
 of th*! link, driv(! in flu; other key with a luimmer on the other 
 Hid<! of the link. After tlu^ key is driven as far in as the judg- 
 
MECHANICS. 41 
 
 ment suggests, measure the width of the slot, so that, if the ope- 
 ration was not performed to a sufficient extent on the first at- 
 tempt, the operator may judge how much to essay at the second, 
 and so on. To prevent, as fa?' as possible, a slot link or quadrant 
 from altering its shape in the process of hardening : Fit into tlie 
 slot, at various parts along its length, pieces of iron of the same 
 diameter as the die intended to work in the slot, and in quench- 
 ing the quadrant, immerse it endwise and vertically. 
 
 Nails into hard wood. To drive. — Dip in grease to assist pene- 
 tration. 
 
 Nuts, Tight, To ease. — To ease a nut that is a little too tight 
 upon a bolt, place it upon the bolt, and, resting it upon an iron 
 anvil or block, strike the upper side with a hammer, turning the 
 nut so that not more than two blows will fall upon the same 
 face. The smaller the nut, the lighter the blows should be, and 
 vice versa. 
 
 Nuts, Tight, To unscrew. — To start a nut that is corroded in its 
 place, so that an ordinary wrench fails to move it, strike a few 
 sharp blows upon its end face ; then holding a dull chisel across 
 the chamfer of the nut, strike the chisel-head several sharp 
 blows, which will, in a majority of cases, effect the object. 
 
 Patterns, Cast-iron. — These should have their surfaces smooth- 
 ed, and be then slightly heated and waxed all over with the best 
 beeswax. 
 
 Patterns for Brass Bed-Pieces. — In making a pattern for 
 a brass bedding in a circular bed, first make the pattern at the 
 same curve as the bed, and then pare off the centre of the crown- 
 bed about ^- inch for every inch of diameter of bore of the brass ; 
 the reasons for this are explained in treating of patterns for semi- 
 octagonal bedding-brasses. 
 
 Patterns for Brasses. — In making a pattern for a brass to 
 fit in a semi-octagonal bed such as is employed in pillar-blocks, 
 and sometimes in the small ends of connecting-rods and axle- 
 boxes : after having made the bed of the brass to the same shape 
 as the seat into which it beds, take off -^ inch in brasses be- 
 low 3 inches bore, or ^ inch in brasses above that size, from 
 the crown face of the brass pattern, for the following reasons : 
 The casting of iron or of brass contracts, in cooling, most at the 
 sides, and the above is to compensate for this contraction. Fur- 
 thermore, it will require only ^^ inch to be cut off the angles to 
 let a brass (having bed-angles at 40°) down ^ inch on the crown ; 
 whereas it will require ^ inch taken off the crown face to let the 
 bed-angles down -^ inch. A strict observance of this rule will, in 
 all cases, save one half the time required to fit such brasses to 
 their places. In brasses whose bed-angles are more acute, a 
 greater allowance must be made. 
 
 Patterns, To fit. — To get a pattern to fit closely over an ir- 
 regular casting having angles, projections, or crooks in it (such 
 as is often required to make a casting with which to patch cylin- 
 ders or junctions of pipes), take a piece of sheet-lead, and ham- 
 mer it lightly with a round pene-hammer, closing it round the 
 casting until it will, by stretching where it is requisite, conform 
 
48 MECHANICS. 
 
 strictly to the sliape of the surface, however irregular it may be. 
 The moulder can then cast a patch from the sheet-lead, making 
 it of any required thickness. 
 
 Patterns, Wooden. — These should never be left in the foun- 
 dry, where they are liable to warp from the excessive range of 
 temperature. 
 
 Pening, Setting work by. — The operation termed "pening," is 
 stretching the skin on one side of work to alter its shape, the 
 principle of which is that, by striking the face of the metal 
 with a hammer, the face of the metal struck stretches, and 
 tends to force the work in a circular form, of which the 
 part receiving the effect of the hammer is the outside 
 circle or diameter. The engraving represents a piece of 
 
 a 
 
 I.,.- at 
 
 :r 
 
 \,^-' 
 
 a 
 
 flat iron, which would, if it were well hammered on the face, 
 a a a, with the pene of a hammer, alter its form to that de- 
 noted by the dotted lines. Or let the rod, (/, shown below be 
 attached to a double eye at one end, the other end requiring to 
 come fair witli the double eye, 6, at the other end ; then, if it is 
 pened perpendicularly on the face, c, of the rod, the stretched 
 skin will throw the end around so that it will come fair with the 
 
 xa 
 
 eye, 6. Connecting-rod straps which are a little too wide for the 
 rod ends may be in like manner closed so as to fit by pening the 
 outside of the ciown end, or, if too narrow, may be opened by 
 pening the inside of the crown end ; l)ut in either case, the ends 
 of the strap alter most in consequence of their lengths, and the 
 strap will require refitting between its jaws. 
 
 Pipes, Gas or Steam, Threads used in screwing : 
 Inside diameter. Tlircads Inside diamctor. TIni-ads 
 
 per inch. I'er inch. 
 
 lU 
 
 111 
 8 
 
 8 
 8 
 8 
 
 _ insid(Mlianictersare 
 
 only estimated. aVtlii'V vary for jjiljes of different strength, the 
 
 i 
 
 
 27 
 
 
 lA 
 
 i 
 
 
 18 
 
 
 2 
 
 1 
 
 
 18 
 
 
 2i 
 
 \ 
 
 
 14 
 
 
 3 
 
 \ 
 
 
 14 
 
 
 3i 
 
 1 
 
 u 
 
 
 lU 
 
 lA 
 
 
 4 
 
 Taper of threads 
 
 A 
 
 per inch f 
 
 )f 1 
 
 pngtli. Thes 
 
MECHANICS. 
 
 49 
 
 thickness varying for the different grades, and the outside diame- 
 ter remaining the same. 
 
 PiSTOX-RiNGS, To open. — Hammer them lightly with a round 
 pene-hammer all round their inside faces. 
 
 PiSTOX-RoD Glands. — If these are rather tight, the piston-rod 
 may be eased bv rubbing the gland up and do%vn the rod, and 
 giy'ing it at the 'same time a revolving motion back and forth at 
 each stroke. Oil must be supplied to the rod to prevent the 
 gland from seizing or cutting. A gland should be chucked in the 
 lathe by the tlange, so that the bore and outside diameter may be 
 turned at one chucking, and thus be true without depending upon 
 the truth of a mandrel. 
 
 Plaster, Inserting screws in. — Make a large hole in the plas- 
 ter and drive in a wooden plug, in which insert the screw. The 
 plug may be first split and a groove cut in each half. 
 
 Pullets, Turning. — Pulleys should be turned either on a man- 
 drel, or else chucked by the arms, since chucking them by the 
 rims springs them out of true. 
 
 PuNXHiNG Metals. — The same elements of resistance enter 
 into the operation of punching as in that of shearing. In short, 
 a punch and die may be considered as shears with circular blades. 
 The coefficient of pressure in punching, for any given area of 
 section, will be exactly that for shearing the same area of sec- 
 
 I 
 
 P 
 
 J 
 
 iff 
 
 SHKENKING METAl-WORK. 
 
 tion, without reference to the thickness of the material. The 
 measure of force necessary to effect the various punchings readi- 
 ly gives the value of the resistance to shearing in cases of ordi- 
 nary metals. This resistance, per square foot, is determined to 
 be, in lbs. : For lead. 392,548 : block-tin, 450.784 : nl'ov of lead 
 and tin, 731,176 ; zinc, 1,843,136 ; copper, 4,083,941 ; iron, 103,- 
 
 ooo. 
 
50 MECHANICS. 
 
 Reducing the Size of Work by shrinking with Fire 
 AND Water. — For reducing the isize of wrought-iron work, the 
 process shown in the following engraving may be employed. 
 a a is the section of a wrought-iron square box or tube, which is 
 supposed to be made red hot and placed suddenly in the water, 
 B, from its end, C, to the point D ; the result is that the metal in 
 the water, from C to D, contracts or shrinks in diameter, and com- 
 presses the hot metal immediately above the water-line, as the 
 small cone at D denotes. If then the box or tube is slowly im- 
 mersed in the water, its form, when cold, will be as in the right- 
 hand figure, that part from C to D maintaining its original size, 
 and the remainder being smaller. 
 
 It must then be reheated and suddenly immersed from the end, 
 E, nearly to D, until it is cold, and then slowly lowered in the 
 water, as before, which will contract the part from D to C, mak- 
 ing the entire length parallel but smaller, both in diameter and 
 bore, than before it was thus operated upon. 
 
 Rolls, To prevent cinders getting between the necks of. — Bore 
 grooves out of the bearings, 1^ inches wide and 4 inch deep and 
 1^ inches apart, put them at an angle of 45° with the face of the 
 brass, and fill up said grooves with soft Babbitt metal. Then 
 when cinder or iron gets in, it will travel but a short distance be- 
 fore it reaches the soft metal, and the motion of the roll will im- 
 bed it therein so that it can not protrude and scoi-e the neck, as it 
 would were it to stick in the brass. 
 
 Rust, To remove, from small hollow castings. — Dip in dilute 
 sulphuric acid 1 part commercial acid to 10 water ; wash in hot 
 lime-water, and dry in the tumbler with dry sawdust. 
 
 Sands and Facings for Castings. — For castings, such as 
 pipes or small cylinders, fine sand, termed No. 1, is used, the fac- 
 ing Ijcing ])liinibago. A good facing for loam castings is made of 
 1 part VVhitehead sand to 3 parts fire-sand. For very fine-faced 
 castings, Albany or Waterford sand is unsurpassed. Another 
 facing for fine castings is 1 part of sea-coal to 8 or 10 of AUmny 
 sand : for heavy castings, however, 1 to 5 will answer 
 
 Saw'-Bladks, Snuill. — Mechanics who want small gig saw 
 blades will find that the steel springs of which hoopskirts are 
 formed will make; caijital ones of any lengths; and they vary in 
 width, so as to l)e suitable for a variety of uses. 
 
 ScRKW-DuiVKKS, The advantage of long. — The reason that a 
 screw is driven more easily into wood l)y a long than by a short 
 Hcrew-driver, is that the tool is held at an angle, and coiisc<|UiMitly 
 the long Hcrew-di-ivcr aiTonls a greater leverage than a short one. 
 If both were st^ciircd ?;(> as to Ix- at right angles to the face of the 
 screw, there would ije no difference in their action. 
 
 SciiRWH, To prevent, getting tight in their nuts. — Plane a key- 
 way or groove in tin; screw, .< in. wide, the full length of the 
 scresv and down to the bottom of the tlireads ; and it will act like 
 a tap, and scrape all tlie hard gummy grease out of the. nut, and 
 always keej) it clean and working free. 
 
 ScuKW and Hrad Holes in finisiikd wouk, 'I'o plug. — Ohio 
 tlie edge of tlie plug ; |(Ut, no glut- in the hole. By this means 
 
MECHANICS. 
 
 61 
 
 the surplus glue is left on tlie surface, and if the plug does not 
 hit the screw, it will seldom show. Set the heads of brads well 
 in, then pass a sponge of hot water over them, filling the holes 
 with hot water. This brings tlie wood more to its natural posi- 
 tion, and closes by degrees over the head of the plug. When 
 dry, sandpaper off and paint, and the putty will not hit the head 
 of the brad. 
 
 Screws, Hints about. — When screws are driven into soft wood 
 and subjected to considerable strain, they are likely to work 
 loose ; in such case, dip tlie screw in thick glue before insertino-. 
 When buying screws, see that the heads are round and well 
 cut ; that there are no flaws in the body or thread part, and that 
 they have gimlet points. A screw of good make will drive into 
 oak as easy as others into pine, and will endure having twice the 
 force brought against it. W^hen there is an article of furniture 
 to be hastily repaired, and no glue is handy, insert a stick a little 
 les.s in size than the hole for the screw and fill the rest of the 
 cavity with powdered resin ; heat the screw sufficiently to meet 
 the resin as it is driven in. 
 
 Screw, To remove. — An obdurate screw may sometimes be 
 drawn by applying a piece of red-hot iron to the head for a 
 minute or two, and immediately using the screw-driver. 
 
 Screw-Threads. — English and American proportions : 
 
 TJie Whitworth Thread. 
 
 Diameter in inches.... A i A I I'iT * I f I 1 
 
 Threads per inch 21 30 18 16 14 12 11 10 9 8 
 
 Diameter in inches li IJ If 1* If If 1^ 2 2i 2i 
 
 Threads per inch 7766554^4^44 
 
 Diameter in inches... 2f 3 3i 34^ 3| 4 4^- 4i 4f 5 
 Threads per inch 3^ 3i 3i 3i 3 3 2f 2| 2f 2f 
 
 Diameter in inches. .. . 5 J 5^ 5f 6 
 Threads per inch 2f 2f 2i 2i 
 
 Angle of threads = 55°. Depth of threads = pitch of screws. 
 (One sixth of the depth is rounded off at top and bottom.) 
 Number of threads to the inch in square threads = 4 number 
 of those in angular threads. 
 
 Standard American Proportions. 
 
 Diameter in inches i ^ I tV i iir I f I 1 
 
 Threads per inch 20 18 16 14 13 12 11 10 9 8 
 
 Diameter in inches If IJ If U If If If 2 2i 2f 
 
 Threads per inch 7 7 6 6 5f5 5 4f4f4 
 
 Diameter in inches 2i 3 3i 3i 3f 4 4f 4f 4f 5 
 
 Threads per inch 4 3f 3i 3i 3 3 2f 2f 2f 2f 
 
 Diameter in inches . . . 5J 5f Sf 6 
 Threads per inch 2f 2| 2f 2i 
 
 Angle of threads = 60'. Flat surface at top and bottom = f of 
 the pitch. For rough bolts, the distance between parallel sides 
 
52 MBCHANICS. 
 
 of bolt-head and nut = 1^ diameters of bolt + ^ of an inch. Thick- 
 ness of head = i distance between parallel sides. Thickness of 
 nut = diameter of bolt. In finished bolts, thickness of head = 
 thickness of nut. Distance between parallel sides of a bolt-head 
 and nut and thickness of nut is -j\- of an inch less for finished 
 work than for rough. 
 
 Softening Bright Work without damaging the Finish. — 
 Place tlie pieces in an iron box, and fill in the interstices with 
 iron turnings ; close the box, lute the cracks witli fire-clay, and 
 heat to a red, allowing the box to cool as slowly as possible. It 
 is a good plan to let the furnace-fires go out and leave the box in 
 the furnace to cool. 
 
 Solder, To flow. — Ordinary solder, 2 parts tin and 1 part lead, 
 will flow smoothly on tin when dipped by previously putting sal- 
 ammoniac on the surface to be tinned. 
 
 Spirit-Leyel, Accuracy of the. — The best length of bubble 
 depends on the length or curvature of the tube, a short bubble 
 being required for u tube with a small radius of curvature, and 
 increasing regularly in proportion with the increase of the radius 
 of curvature. 
 
 Springs, Steel. — To find elasticity of a given steel-plate spring: 
 Breadth of plate in inches multiplied by cube of the thickness in 
 V,; in., and by number of plates. Divide cube of span in inches by 
 l)roduct so found, and multiply by l.GO. Result, equal elasticity 
 in -^ in. per ton of load. To find span due to a given eladicity and 
 number and size of plate : Multiply elasticity in sixteenths per ton 
 by breadth ol plate in inches, and divide by cube of the thickness 
 in inches, and by number of plates ; divide by 1.G6, and find 
 cube-root of quotient. Result, e(iual span in inches. To find num- 
 ber of plates due to a given elasticiti/, span, and size of jdates : 
 Multii)ly the cube of the span iu inches by 1.G6. Multiply the 
 elasticity in sixteenths by the breadth of the plate in inches, and 
 by the cube of the thickness in sixteenths ; divide the former 
 ])roduct by the latter. The (juotient is tlie number of plates. 
 To find the working xtnngth of k given steel-plate spring : Mul- 
 tiply the breadth of plate in inches by the square of the thick- 
 ness in sixteenths, and by the number of plates. Multiply also 
 the working span in inches by 11.:} ; dividt* the former product 
 by the latter. Result, equal workiug strength in tons burden. 
 To find sptin due to a ginrn. Ktn ngtii and nunibrr and xize of plate : 
 Multiply tlie breadth of ])late in inches by the square of the 
 tiiickness in sixteenths, and liy the nm.iber of ])latea ; multiply 
 also tlie strengtli in tons by 11.3 ; divide the former prcaict by 
 the latter. Result, e(|ual working span in inche.s. To find the 
 numher of pbttes due to a girc/i ntnngtli, sp • and size of plate : 
 M ''iply till' strength in tons by sjjan in h .'S, and (livide l)y 
 1 • muliiply also the ijrcadlh of jdatt; in iii.-.i'S by tlu; scpiaro 
 
 of tlie thickiirss in sixteeiitliB ; divide the former product by the 
 latter. |{esult, ecpial nuiiilier of jilates. The span is that due 
 to tlie form of the spring loaded. Extra thick jilates must be re- 
 placed by an equivalent number of plates of the ruling tliickness 
 
MECHANICS. 53 
 
 before applying the rule. To find this, multiply the number of 
 extra plates by the square of their thickness, and divide by the 
 square of the rulins: thickness ; conversely, tlie number of plates 
 of the ruling thickness to be removed for a given number of 
 extra plates may be found in the same way 
 
 Springs, To reduce elasticity of. — A well-tempered bar-spring 
 will lose much of its elastic strength by filing off a very thin 
 scale from the surface. 
 
 Steel, Advantage of holes drilled iu. — The advantage in 
 tensile strength, when holes are drilled in steel rather than 
 punched, is 25.5 per cent. 
 
 Steel, Cast, To weld. — Apply powdered borax to the weld 
 while heating it in the fire. If the steel is made too hot, it will 
 crack during the hammering process. 
 
 Steel, Cast, Welding compound for. — Mix i lb. saltpetre aud 
 I lb. oil of vitriol in 2 gallons hard water ; heat the steel to a 
 blood red, and coo! in the mixture before welding. Then reheat, 
 in sand, and weld by hammering as usual. 
 
 Steel, Fire for tempering. — In hardening and tempering steel, 
 a clean charcoal, anthracite, or coked bituminous coal fire is re- 
 quired ; such as is fit for taking a forging heat on iron is entirely 
 uufit for hardening purposes. The sulphur contained in the 
 coal combines with the steel to form sulphuret of iron, and ruins 
 its texture. 
 
 Steel, Tempering. — The colors shown at different temperatures 
 Fahr. are as follows: Very pale yellowish, 430" ; pale straw, 
 450° ; vellow, 470° ; brown, 490° ; mottled brown, 510° ; purple, 
 530° ; bright blue, 550° ; blue, 560° ; dark blue, 600°. 
 
 Steel, To demagnetize. — (1) Heat it to a red heat, and allow it 
 to cool slowly. (2) Place the steel on a magnet, with the same 
 poles touching the same poles of the magnet, and repeat tlie 
 operation tili total demagnetization has taken place. 
 
 Steel, To remove blue color from. — (1) Use 1 part oil of vitriol 
 to 10 parts water. (2) Dip the articles in a strong solution of 
 cyanide of potassium nearly boiling. (3) Dip the article in hy- 
 drochloric acid, and quickly rinse in clean water. 
 
 Tempering steel for drilling rock.— Be careful not to overheat 
 it in hardening and forging, and quench in salt water, drawing to 
 a brown color. 
 
 Tempering, The color-tests for.— Says Mr. J. Richards : " Pro- 
 cure eight pieces of cast-steel, about 2 in. long by 1 in. wide, 
 and f of an inch thick ; heat them to a high red heat, and drop 
 them into a salt-bath. Leave one without tempering, to show 
 the white shade of extreme hardness, and grind off and polish 
 one side of each of the remaining seven pieces. Then give them to 
 an experienced tool-maker to be drawn to seven various shades of 
 temper, ranging from the white piece to the dark blue color of 
 soft steel. On'the backs of these pieces paste labels, describing 
 the technical name of the shades and the general uses to which 
 tools of corresponding liardn(>ss are adajited. This will form an 
 
54 MECHANICS. 
 
 interesting collection of specimens, and accustom the fye to the 
 various tints, whicli will, after some experience, be instantly re- 
 cognized when seen separately." 
 
 Tinning small castings. — Clean, and boil them with scraps of 
 block-tin in a solution of cream of tartar. 
 
 Water-wheel, Steps for. — No step or foot-bearing of metal is 
 equal to one of good oak or rock-maple. 
 
 Zinc, Stamping. — In stam]iing sheet-zinc in dies, much waste 
 occurs from the small difEerence between the melting-point and 
 the temperature at which sheet-zinc should be stamped to get the 
 best effect. To obviate this waste, heat the zinc by dipping in 
 oil at the proper temperature. 
 
ENGINEERING. 
 
 TESTIXG THE STRENGTH OF MATERIALS 
 
 BY PROF. R. H. THURSTOX. 
 
 The engraving whicli accompanies this article illustrates a 
 very convenient, yet quite accurate, method of determining the 
 strength of materials, whicli has been devised by the writer. 
 The test-piece is made by catting, from the piece of metal 
 of which the strength is to be determined, a piece about 3 in. 
 
 TESTING METAXS. 
 
 long and 1 in. square. At the middle of its length, a part is 
 turned cylindrical in form and 1 in. long, with a diameter of + in. 
 if of iron, or 'i in. if the metal is steel. The test-piece thus made 
 is fastened in the vise, as shown in the engraving, and a long- 
 handled wrench is attached to the projecting head. A spring- 
 
OO SC^'GINEEKING. 
 
 balance is secured to the end of this wrench, and the experimen- 
 ter twists off the head by pulling on this sprinj.r-balauce, as seen 
 in the illustration. The" balance should be capable of indicating 
 weights of fifty pounas or more. By simply painting the scale 
 of the balance with white-lead, or smearing it with tallow, and 
 by springing the pointer so that it will touch the surface, a re- 
 cording apparatus may be improvised which will indicate the 
 maximum strain reached during the test. 
 
 In testing, the experimenter i)ulls steadily on the balance, gra- 
 dually increasing the force exerted, and watching carefully, and 
 noting the action of, the test-piece and the balance, until fracture 
 occurs. A resistance, which is apparently quite unyielding, is 
 ft'lt at first ; this is suddenly observed to be succeeded by a grad- 
 ually increasing distortion of the test-piece, accompanied by an 
 increasing resistance, up to the point of the commencement of 
 rupture. From the latter point, the resistance becomes less and 
 less, finally ceasing when the test-piece fails apart. By conduct- 
 ing the operation very carefirily, and noting resistances very accu- 
 rately, all of the following important points may be determined : 
 
 The limit of elasticity is the point at which the yielding first 
 commences. Note the reading of the balance at this point and 
 the angle of distortion. The last quantity is the measure of the 
 stiffness of the metal. The most rigid pieces are, of course, those 
 which yield the least with a given amount of force. After the 
 piece has been twisted so far as to have taken a set, the pull may 
 be relaxed, and the distance which the piece springs back is to be 
 noted. The elaKticity of the metal is measured by this recoil. 
 The ductility of the metal is measured by the extent of yielding 
 which occurs before fracture takes place. The rexiliencc of the 
 metal — which is the name given its power of resisting shock — is 
 very closely proportioned to its strength multiplied by its ductili- 
 ty. Therefore, to ascertain what blow would be resisted by it 
 without its taking a set, it is simidy necessary to multij)ly the re- 
 sistance at the limit of elasticity by the amount of distortion ob- 
 served within the elastic limit. The hom<>(j( neity of the material 
 is indicated by the smoothness and regularity with which the 
 metal changes in its power of resistance as the deformation pro- 
 gresses. 
 
 In making such a series of experiments, it is usually found 
 be.st to first select a well-known and good brand of the kind of 
 metal which it is i)roposed to test, and, by a set of exi)erinu'iits 
 on test-pieces cut from it, to determine what, with the particular 
 arrangement of aj^paratus chosen, is the resistance registered by 
 the l)alance, and what are the characteristics of the metal as 
 shown by the method here described. By a careful comi)arison 
 of the behavior of tlie metal of which the <iuality is desired to be 
 learned with tliis .standard set of satnides, tlie operator soon 
 learns to judge cpiickly and accurately of the value of his mate- 
 rial for any specified purpose. 
 
 Ah the tensile strength of a metal is usually very closely pro- 
 IK)rtional to tlie resistance to torsion, this also enables a very sa- 
 tisfactory deteriuinalion of the value of the metJil for resisting 
 tension to be obtaini'd. In tht^ autographic recording nuichine, 
 built by the Meclianical Laboratory of the Stevens Institute of 
 
ENGINEERING. 57 
 
 Technolooy, these results are permanently inscribed upon a sheet 
 of profile-paper, the pencil of the ajiparatus writing a diagram or 
 curve which is a record of all the circumstances modifying the re- 
 sisting power of the metal while under test. The rule being ap- 
 plied, the torsional, and approximately the tensile, resistance is 
 read off at a glance, and tlie position of the elastic limit, the ho- 
 mogeneousness, the elasticity, the stiffness, the ductility, the 
 resilience, are all found fully indicated by the diagram, and can 
 be, at any subsequent period, shown by means of this automati- 
 cally produced record. On these records, the tensile resistance is 
 louud to be about 25,000 pounds per square inch for each inch in 
 height of the diagram. 
 
 The peculiar method of fracture here adopted is well adapted 
 to exhibit in the surfaces of the break any peculiarity of the 
 metal. If homogeneous, it will show a uniform and characteris- 
 tic fracture ; if seamy, it will be found to have cracks extending 
 spirally around it ; if of cast-iron, the character of the ruptured 
 surfaces will at once reveal to the experienced eye whether the 
 metal is fine or coarse grained, a dark foundry or a light forge 
 iron, and whether of close or open texture. If of steel, it will be 
 readily seen whether it is " high" or " low," whether tool steel 
 or of the machinery grade. Whatever the character of the ma- 
 terial, the eye, experienced in such kinds of observation, will at 
 once detect it, while the record of the experiment, or the " strain- 
 diagram," will give the exact data of resistances, and will be a 
 check upon the judgment thus formed. 
 
 THE ENGINE AND ITS APPENDAGES. 
 
 COXDENSERS, Gain from the application of, to steam-engines. — 
 In the early days of the steam-engine, very low pressure was or- 
 dinarily employed for engines with condensers, while, on the con- 
 trary, what was considered a very high pressure was adopted for 
 engines that exhausted into the atmosphere. Hence arose the 
 terms high and low pressure engines, the former being engines 
 with, and the latter without, condensers. At present, a high 
 pressure of steam is ordinarily carried in both kinds of engines, 
 so that the terms do not describe the two varieties as well as 
 formerly. Many engineers prefer to class engines as condensing 
 and non-condensing, rather than as high and low pressure ; and 
 this classification is generally considered the more correct of the 
 two. One who regards economy puts in a condensing engine, 
 if he has plenty of water in the locality ; and many old non-con- 
 densing engines are being fitted with condensers, under the more 
 enlightened engineering practice of the present time. 
 
 It may be fairly assumed that a non-condensing engine has, on 
 an average, at least 2 lbs. per square inch back pressure on the 
 piston. By the application of a condenser, it might be expected 
 
58 Ei«fGINEERi:NG. 
 
 tliat there would be a negative pressure of 10 lbs. per- sq. inch on 
 the back of the piston, so that the piston pressure would be in- 
 creased bj 12 lbs. In this assumption, an allowance is made for 
 the power required to work the air-pump, and the engine is sup- 
 posed to be at least 7o horse-power. For an engine smaller than 
 this, it would be better to allow an increase in the positive pressure 
 of not more than 10 lbs. per square inch. As the condenser, by 
 decreasing the back pressure on the piston, adds just as much to 
 the positive pressure, it is plain that a lower pressure of steam 
 can be used, or the steam may be cut off at an earlier point of the 
 stroke. The gain in either case can be a})])roximately calculated. 
 If the gain in positive pressure produced by the reduction in 
 back pressure be multiplied by 100, and divided by the mean ef- 
 fective pressure on the piston, it will give the percentage of gain 
 in pressure due to the condenser. 
 
 Thus, if the mean effective pressure on the piston is 30 lbs. per 
 square inch, the gain in pressure will be 100 times 12, or 1200, 
 divided l)y 30, which is 40 per cent. Now suppose that before 
 the condenser was attached, tiie steam was cut off in the cylin- 
 der at half stroke ; under the new conditions the required mean 
 effective pressure can be obtained with a lower boiler pressure 
 than before. Before the condenser was in use, it would be ne- 
 cessary to maintain a pressure in the boiler of about 58 lbs. per 
 square inch by gauge, to give a mean effective pressure of 30 lbs. 
 on the piston ; while with an increase of 12 lbs. in the effective 
 pressure, by the application of the condenser, a boiler pressure of 
 about 39 lbs. would suffice. As the weight of steam \>eT cubic 
 foot at 58 lbs. pressure is 0.17481 lbs., and only 0.132 lbs. at 3i» 
 lbs. pressure, there would be a saving of about 24.5 jier cent in 
 the amount of steam reijuired to run the engine. Instead of re- 
 ducing the steam pressure after attaching a condenser to an en- 
 gine, it might be better to maintain the same pressure in the 
 boiler, and cut off the steam at an earlier ])art of the stroke. In 
 the case under consideration, tlie increase in 12 lbs. of the effec- 
 tive pressure would permit of closing tlie steam port a little be- 
 fore the completion of one third of the stroke ; and supposing 
 tliat the clearance space in the cylinder amounts to 5 i>er cent of 
 the capacity of till- (-ylindcr, the (juantifics of steam recpiiri'd ])er 
 stroke, before and after tlie use of tlie condenser, would be in the 
 ratio of 550 to 303, so that there would be a saving of 34 per 
 cent. 
 
 The example given represents a case in ordinary practice. By 
 varying the data, of rour.se a greater or less amount of saving 
 would re.suh ; but with an engine in good condition, it is gene- 
 rally saf(^ to estimate that a saving from 20 to 25 ])er cent of the 
 amount of steam usc-d, and, coiise(iuently, of the consumption of 
 coal, will be realized by tlu^ application of a condenser. Indeed, 
 it is not unusual for manufacturers to guarantt^e this amount of 
 saving in converting a non-condensing into a condensing engine. 
 
 B. 
 
 f^OTTON Machinkuy, Power required Id drive. — The following 
 are fair a|)proxi mate rules : Cotton openers, I liorse-power per 
 l(MH) lbs. cotton delivered. Cotton jiickers, 3 liorse-|)ower per 
 1000 lbs. <:otton delivered. Cotton canis, v'n horse ])ower per lb. 
 
ENGIXEERI]S'G. 59 
 
 cotton delivered per day, and, at 125 revolutions per minute, 0.13|- 
 liorse-power. Cotton cards, best practice, -^ horse-power per 
 revolution per minute. Railway heads, breakers, 1 horse-power 
 per each 10 yards per miuute. Railway heads, finishers, 0.001 
 horse-power "per revolution per minnte. Drawiug-frames, 0.003 
 horse-power per revolution per minute. Spindles, 0.005 horse- 
 power per spindle per 1000 revolutions. Damp weather adds 
 10 or 13 per cent ; methods of banding may make equally great 
 variations. Looms require from 0.1 to 0.35 horse-power each. 
 Pickers take 4 to 6 horse-power. Cloth shears from 3 to 4 horse- 
 power. 
 
 Cylinders, Balancing heavy. — The cylinder, being keyed upon 
 its axle as it is intended to run, is lifted by a tackle or crane, and 
 lowered so that each of its journals rests upon a stout steel 
 straight-edge placed so that its upper surface is exactly level and 
 parallel with its fellow. These straight-edges should not only be 
 so rigid as to suffer no sensible deflection from the weight of the 
 cylinder, but they should be very hard and smooth, and great 
 care should be taken to keep them free from indentations. The 
 journals of the cylinder must also be round and polished. The 
 cylinder can now be loaded on its lighter side, or vice versa, until 
 it will remain perfectly motionless when stopped in any part of 
 its revolution. 
 
 Cylinders, Locomotive, Placing in line. — To test the ac- 
 curacy of the work after the bed-piece has been permanently fixed 
 to the boiler, clamp a cylinder to its seat on the bed-piece, and fit 
 a wooden cross (with a pin-hole through its centre) to the bore of 
 the cylinder at its front end ; then pass a fine strong line through 
 the hole, and extend it back so that it shall occupy a point ex- 
 actly at the intersection of the central line of the driver-axle 
 with the vertical plane of motion of the centre of the crank-pin 
 and connecting-rod ; draw the line taut and fasten it in this posi- 
 tion ; then apply callipers or a gauge at the rear end of the cylin- 
 der, between the surface of the bore and the line, above and be- 
 low and right and left of the line ; and if the cylinder is in line, 
 the four distances will of course be exactly the same. It is essen- 
 tial that the tAvo horizontal distances should coincide exactly, and 
 that the central lines of the two cylinders of a locomotive should 
 be exactly parallel with each other, but for obvious reasons the 
 exact coincidence of the two vertical distances is not essential to 
 the efficiency or correct Avorking of the engine. 
 
 Instead of a Avooden cross, as aboA'e mentioned, a more conve- 
 nient instrument, made of metal, may be proA^ided, consisting of 
 four bevel gears. A, which serve also as nuts, which work tour 
 sockets, B, with threads cut on their inner ends, all neatly fitted 
 to a light casting, E, haA'ing a fine central hole for the line, as 
 shown. A central gear, C, Avorks the four gears, of course all at 
 the same time. SeA-eral sets of steel rods, D, may be provided if 
 necessary, of different lengths, and thus render the instrument 
 universal in its application, each set of rods serving for cylinders 
 varying tAVO inches, more or less, in the diameters of their bores. 
 
 To determine whether a cylinder of an old engine is in line : 
 Remove the front head of the cylinder, the piston, the stuffing- 
 
LiO 
 
 KNGINKKKIXG. 
 
 box gland, and the tro^s-head ; apply the cross and line, as above 
 directed, extendiufj the line through the piston-rod hole in the 
 rear head to a point exactly central with the crank-pin when the 
 crank is at its dead point ; draw tlie line taut, and, it the cylinder 
 
 rl.ACINO LOCOMOTIVE CVLlNXJEItS IN l.l.NE. 
 
 is correctly in range, the line will occupy a central position in the 
 stuffing-box, which maybe determined as before directed. If the 
 cross-head guides are parallel with the line, both vertically and 
 laterally, they are also correct. 
 
 C'VLIXDKUS, Thick. — Thick cylinders are those in which the 
 thickness is considerable in comjjarison with the internal dianu'- 
 ter. To find tlu; bursting ])ressure of a thick cylinder, take the j)ro- 
 ductof (1) tlie trnacityof tin; nuiterial in ixjuihIs per scjuare inch, 
 and (2) tli(! tliickness of the cylinder in indies, and divide the ])ro- 
 duct Ity th<^ sum of (1) the thickness in inches, and (2) the internal 
 radius of the cylinder in inclu-s. Tints u cylin<ler with an internal 
 radius of 4 indies, and a thickness of 5 iiu-hes, if made of cast- 
 iron having a tensile strength of Ki, ()()() lbs. ])er 8(juare inch, lias 
 a biir.-tin;^ jjre.ssure of HHHH.'J lbs., Ibis being the product of 
 10,000 and 5, divided by tlie sum of 4 and 5. B. 
 
 FInoinkku, Duties of the. — The ordinary daily duties of an en- 
 gineer are as follows : On coming in \]ir morning, he sliould first 
 ascertain the amount of water in tin; l>oiler ; and, if tbat is all 
 right, j)roceed to raisi- steam, eifber cleaning and si)rea(ling tlie 
 
ENGINEERING. 61 
 
 fire, if it has been banked, or making it up, if it has been hauled. 
 A fire is kindled in the boiler in essentially the same manner as 
 in a stove, wood and sliaviugs first being ignited, and then cover- 
 ed with coal. In starting the fire, it is a good plan to cover the 
 back of the grate with coal, to prevent the passage of cold air 
 through the tubes. In getting up steam, the safety-valve should 
 be raised a little, to permit the escape of air from the boiler. 
 Having got the fire under way, the engineer should wipe off the 
 engine, fill the oil-cups, and make any adjustments that may be 
 necessary, such as tightening keys and screwing up joints or 
 glands of stuffing-boxes, and shotild see that the cylinder-cocks 
 are open. When steam is raised, he shotild open the stop-valve 
 and start the engine ; after which, if a part of his duty is to at- 
 tend to the shafting, he should examine and oil it. Then he 
 should get out the ashes, provide a supply of coal, and screen it, 
 if necessary, and proceed to make everything tidy around the en- 
 gine and boiler. Throughout the daj', he should keep a watchful 
 eye on the fire, the water, the steam, and the engine. In manag- 
 ing the fire, care should be taken to have the furnace-door open 
 as little as possible ; and, if steam is formed too rapidly, the fire 
 should be regulated by closing the damper and ash-pit doors. In 
 regulating the height of the water, it is a good plan to keep a 
 steady feed, and maintain the height constant. If it is found 
 that the water is falling, the engineer should discover whether it 
 is caused by a leak, or by the refusal of the pump to work. He 
 can tell whether the pump is working by the sound of the check- 
 valve falling after each stroke, or by feeling the feed-pipe or 
 check-valve. A pump will not feed when the temperature of the 
 water is very high, unless it is specially adapted for pumping hot 
 water ; and if it refuses to work from this cause, the temperature 
 of the water should be reduced. A pump will not deliver water 
 if the proper valves are not opened, if its passages are choked, or 
 if its packing is defective. It would be necessary to examine the 
 pump at once, and endeavor to discover and remedy the difficulty. 
 If the water falls in the boiler on account of a leak, it can some- 
 times be temporarily repaired with a plug, or the pump can be 
 run faster, so as to keep up the water until stopping-time. If 
 this is not possible, the fire should be hauled, and the engine al- 
 lowed to ran as long as there is sufficient steam -pressure. In case 
 the engineer finds that the pump is not feeding, and he has a fair 
 supply of water in the boiler, he should at once examine the pump, 
 and endeavor to remedy the trouble without stopping the engine. 
 If he does not succeed, however, before the water falls below the 
 level of the lowest gauge-cock, he should haul the fire, and let the 
 engine run as long as the steam-pressure is sufficient. If he has 
 been called away from the boiler, and on his return finds that the 
 water is below the level of the lower gauge-cock, he should imme- 
 diately ascertain the steam-pressure, and if it is rising rapidly he 
 should haul the fire at once. If the steam-pressure is about the 
 same as usual, he should examine the pump ; and if it is not de- 
 livering water, he should haul the fire. If the pump is feeding, 
 he may run it faster, watching the steam-gauge carefully. If 
 the pressure does not fall, he should stop the pump and haul the 
 fire. In any case the engine should not be stopped until the steam- 
 
62 ENGINEERING. 
 
 ]iressiire is considerably reduced. The engineer should ho very 
 l):irticular, on findhig the water low, to examine the steam-gauge 
 at once ; and if the pressure is unusually high, he should haul 
 the fire without delay. 
 
 A boiler foams or primes either because it has insufficient 
 steam room, or on account of dirt or grease in the boiler or the 
 feed-water. The trouble is often experienced with new boilers, 
 and disappears w'hen they become clean. Priming is dangerous, 
 if much water is carried over with the steam, as it is difficult to 
 maintain the water-level constant, and the engine is liable to be 
 broken by the water in the cylinders. If the trouble is caused 
 by insufficient steam-room, it can sometimes be partially over- 
 come \)y increasing the steam pressure, and throttling it down to 
 the ordinary working pressure in the cylinder ; but the only ef- 
 fectual way is to provide more steam-room. If the priming is 
 due to dirt or grease in the boiler, the engineer should blow off 
 frequently, and clean the boiler every few days. In lilowing off, 
 it is well to raise the water-level in the boiler by putting on a 
 strong feed, and then blow down below the level that is ordi- 
 narily maintained. It is very often the case that the water-level 
 is higher when the engine is running than it is when none of 
 the steam is being used. The engineer should ascertain how 
 much higher the water rises in such a case, so as to have a ])ro- 
 per quantity of water when the engine is stopped. B. 
 
 Engine for a row-boat. — For an ordinary Wliitiliull row-boat, 
 18 feet long, to run at a si)eed of 8 miles per hour, the engiiu> 
 should have two cylinders, 2 in. diamt^t(!r and 8 in. stroke ; tubular 
 boiler, 24 to 2S iu'-h(;s iu diameter, 4 feet high ; propeller, 22 to 
 24 inches in diameter, with ',i feet pitch. 
 
 Engines and Boii-eus, Small. — By the aid of the accompany- 
 ing table, the effective horse-power (that available^ for useful 
 work) of small engines can b(! approximately determined. The 
 tal)le is designed for non-cond(!nsing engines, with cylinders uj) 
 U) G inches in diiuneter, and for piston-s|)eeds u]) to 400 feet a mi- 
 nute ; the connection of the engine witli tlie boiler being sup- 
 posed to be tolerably direct, tlu^ ]>ortsand pipes heing of siitli<'ient 
 sizes, and tlie steam-valve closing wiien tiie piston has nuide 
 three <|uarter3 of the stroke. As the tabh; is designed for avcrnf/c 
 conditions, it is evident that it wiil give rc^sult.s that are too large 
 in som<! casf'H, and too small in othei's. 
 
 /. — To find the linrKC-ixxncr of itii iiif/iiie rornxjiiiiKliii;/ to a (jlrcii, 
 dunneter of fiflindi r, Iciujth <f MroliC, inniiher of rei'oli/tioiix per 
 minute, and pirKsure of steam in tlie boiler. (1) Multijily the 
 length of strokt! in inches by the number of revolutions i)erjninute, 
 and divider the ])roduct by (>. Tin^ result is the ]>iston-8]>eed in 
 fret per minute;. (2) Find tin; nuniluT in the table the nearest 
 to the given Hteam-]iressure anil calculatiHl ])iston-s])eeii, and 
 multiidy it by 0.7804 times the sipiaro of the diann'ter of the pis- 
 ton in in(;hes. Krample: An engine has a cylinder 2 inclics in 
 diainetiip, and a lenjrlh of stroke of 2 inclies. It makes 400 revo- 
 lutifins a minute, imd the boiler pressure is 50 pounds jier sfpian; 
 inch. Alls.: 'I'wice 400 is HOO. ,S((0 ilivhled by (lis \:V.',k. t'le piston- 
 Hpeed in feet per minute. (I!) 'I'lie nearest piston-speed iu lablo 
 
ENGINEKBING. 
 
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64 
 
 ENGINEERING. 
 
 is 130 feet, and the number in table corresponding to speed of 100 
 and pressure of 50, is 0.074 ; the number for speed of 30 and same 
 pressure is 0.022 ; required number is sum of 0.074 and 0.022, or 
 0.096, corresponding to speed of 130 and pressure of 50. The pro- 
 duct of 4 and 0.7854 is 3.1416, and the product of 0.096 and 
 3.1416, or the required horse-power, is 0.3-|-. 
 
 //. — Dlnineter in inches of cylinder required for a gicoi horse- 
 power, piston-speed, and boiler-pressure. (1) Find in the table the 
 number nearest to the given piston speed and steam-pressure. (2) 
 Multiply the number obtained in (1) by 0.7854. (3) Divide the 
 given horse-power by the quantity obtained iu (2). (4) Take the 
 square root of the quantity obtained in (3). 
 
 Exdmple. — What should be the diameter of cylinder of an 
 engine developing 2 horse-power, with a piston-speed of 150 
 feet a minute, and a boiler-pressure of 100 pounds per square 
 inch V (1) The number from the table is the sum of 0.161 and 
 0.081, or 0.242. (2) Tlie i)roduct of 0.242 and 0.7854 is 0.1900()(iS. 
 (3) The quotient of 2 divided by 0.1900668, is about 10.5226 (4) 
 The square root of 10.5226 is 3.244-, or about 3J inches, the re- 
 quired diameter of cylinder. ' 
 
 III. — The number of pounds of water required to be ewiporaled per 
 hour for each Jiorse-poiper exerted, and for various boiler-pressures, 
 may be approximately estimated from the accompanying table. 
 
 Pressure of 
 
 Pounds of 
 
 Pressure of 
 
 Pounds of 
 
 steam in 
 
 vattT per 
 
 steiini ill 
 
 water per 
 
 boiler by 
 
 ett'ective 
 
 boiler by 
 
 cftective 
 
 gauge. 
 
 horsu-power 
 
 gauge. 
 
 horse-power 
 
 
 pur hour. 
 
 
 per hour, 
 
 10 
 
 118 
 
 60 
 
 75 
 
 15 
 
 Ill 
 
 70 
 
 71 
 
 20 
 
 105 
 
 80 
 
 68 
 
 25 
 
 100 
 
 90 
 
 65 
 
 30 
 
 93 
 
 100 
 
 63 
 
 40 
 
 84 
 
 120 
 
 61 
 
 50 
 
 79 
 
 150 
 
 58 
 
 It is convenient, in calculations of the amount of water evapo- 
 rated at various i)ressures and from various temperatures of feed, 
 to reduce ihcm to a common standard, namely, the ecjuivaliait 
 amounts that would be chaiigtid into steam of atmospht^ric ])re8- 
 Bure, if the temperature of feed was 212 Fahrenlieit ; or, as it is 
 commonly called, to evaporation " from and at 212°." Two 
 tables are ap])ended, for the i)urpo8(! of facilitating this reduction. 
 The second table is taken from Professor Rankiue'a " Treatise 
 on the Steam J'higine." 
 
 Pressure and Temperature of Steam. 
 
 I'rcKKurc 
 by gauge. 
 
 
 
 10 
 
 20 
 
 Ten 
 
 peiiilure 
 ircniicil. 
 
 ..212" 
 
 ..239" 
 
 250" 
 
 Pressure 
 by gauge. 
 
 60 
 
 70 
 
 80 
 
 90 
 
 T. 
 
 Miperature 
 ilneuheit. 
 
 . .307° 
 
 -.316" 
 
 .324' 
 
 30 
 
 
 .274". 
 
 .287' 
 .298" 
 
 . 331" 
 
 40 
 
 100 
 
 
 . 338' 
 
 50 
 
 110 
 
 
 . .344 
 
EXGINEEKING. 
 
 65 
 
 Pressure 
 
 by gauge. 
 
 120... 
 130. . . 
 140. . . 
 150. . . 
 160. . . 
 
 Temperature 
 Fahrcuheit. 
 
 .350° 
 .356° 
 361° 
 .366° 
 .370° 
 
 Pressure 
 
 by gauge. 
 
 170. . . 
 180. . . 
 190. . . 
 200. . . 
 
 Temperature 
 Fahrenheit. 
 
 ..375° 
 ..379° 
 ..384° 
 ..388° 
 
 Factors of Evaporation. 
 
 Tempe- 
 rature 
 of the 
 steam. 
 
 212°.... 
 
 230° 
 
 248° 
 
 266° 
 
 284°. ... 
 302°.... 
 
 320° 
 
 338° 
 
 356° 
 
 374° 
 
 392° 
 
 410°. . . . 
 
 Temperature of the feed-water. 
 
 1.19 
 1.20 
 1.20 
 1.21 
 1.21 
 1.22 
 1.22 
 1.23 
 1.2;3 
 1.24 
 1.24 
 1.251 
 
 1.17 
 1.18 
 1.18 
 1.19 
 1.20 
 1.20 
 1.21 
 1.21 
 1.22 
 1.22 
 1.23 
 1.23, 
 
 1.16 
 1.17 
 1.18 
 1.18 
 1.19 
 1.19 
 1.20 
 l.£0 
 1.21 
 1.22 
 
 1.13 
 1.14 
 1.14 
 1.15 
 1.16 
 1.16 
 1,17 
 1.17 
 1.18 
 1.18 
 1.19; 
 1.20 
 
 104° 
 
 122° 
 
 140° 
 
 158° 
 
 176° 
 
 1.11 
 
 1.10 
 
 1.08 
 
 1.06 
 
 1.04 
 
 1.12 
 
 1.10 
 
 1.08 
 
 1.06 
 
 1.04 ' 
 
 1.13 
 
 1.11 
 
 1.09 
 
 1.07 
 
 1.05 . 
 
 1.13 
 
 1.11 
 
 1.09 
 
 1.07 
 
 1.00 i 
 
 1.14 
 
 1.12 
 
 1.10 
 
 1.08 
 
 1.06 
 
 1.14 
 
 1.12 
 
 1.11 
 
 1.09 
 
 1.07 
 
 1.15 
 
 1.13 
 
 1.11 
 
 1.09 
 
 1.07 
 
 1.15 
 
 1.14 
 
 1.12 
 
 1.10 
 
 1.08 
 
 1.16 
 
 1.14 
 
 1.12 
 
 1.10 
 
 1.08 
 
 1.17 
 
 1.15 
 
 • 1.13 
 
 1.11 
 
 1.09 
 
 1.17 
 
 1.15 
 
 1.13 
 
 1.11 
 
 1.09 
 
 1.18 
 
 1.16 
 
 l.:4 
 
 1.12 
 
 1.10 
 
 I 
 
 194° 212° 
 
 1.02 
 1.02 
 1.03 
 T.04 
 1.04 
 1.05 
 1.05 
 1.06 
 1.06 
 1.07 
 1.07 
 1.08 
 
 1.00 
 1.01 
 1.01 
 1.02 
 1.02 
 1.03 
 1.03 
 1.04 
 1.04 
 1.05 
 1.06 
 1.06 
 
 To illustrate tlie use of the tables, suppose an engine of G 
 liorse-power is supplied with steam at a .pressure of 50 pounds 
 ]ier square inch, and that the temperature of the feed-water sup- 
 plied to the boiler is 160". It is required to find how much water 
 must be evaporated per hour" from and at 212 " for the engine. 
 The temperature of steam having a pressure of 50 pounds is 298°. 
 In the table of " Factors of Evaporation," the factor correspond- 
 in<r to a steam temperature of 302° and a feed temjierature of 158° 
 (which are the numbers in the table nearest to the given ones), 
 is 1.09. Now this engine requires an evaporation of 6 times 79, 
 or 474 pounds of water per hour, at a pressure of 50 pounds, or 
 an equivalent evaporation " from and at 212"" of 1.09 times 474, 
 which is equal to 516.66 pounds. 
 
 IV. — To find the proportions suitable for a boiler whicJi is to have 
 a ffive/i evaporation, (a) To ascertain the grate-surface in square 
 feet : Divide the number of pounds of water to be evaporated per 
 hour, from and at 212% by 75, for cylinder boilers ; by 77, for flue 
 boilers ; by 78, for tubular boilers ; by 80, for locomotive and ver- 
 tical boilers. 
 
 Example. — Suppose that a cylinder boiler is to be proportioned 
 for an evaporation of 500 lbs. of water per hour, at a pressure of 
 75 lbs., the temperature of the feed-water being 80°. The equiva- 
 lent evaporation will be 1.17 times 500, or 585 lbs., and the grate- 
 surface 585 divided by 75, or 7-ro- square feet. 
 
 (b) To ascertain the heating surface in square feet : Multiply the 
 grate-surface by 11, for cylinder boilers ; by 17, for flue boilers ; 
 by 30, for tubular, locomotive, and vertical boilers, (c) To ascer- 
 tain the cross-section of flues or tubes in square feet : Multiply the 
 grate-surface by 0.134. This is an average value for good practice, 
 &nd it can be varied between the limits of 0.135 and 0.143, as may 
 
66 ENGINEERING. 
 
 be most convenient. ((?) To ascertain the length of hoiler : Cylin- 
 der boilers should be from 10 to 13 times the diameter ; flue 
 boilers from 5 to 6 times the diameter ; tubular boilers, and the 
 shells of locomotive and vertical boilers, from 3 to 3i times the 
 diameter. There is very great variation from these figures in 
 practice ; but the numbers given al)ove represent the most gene- 
 ral limits, so far as they can conveniently be classified. 
 
 Example- — What are the dimensions of a tubular boiler for an 
 engine that is to develop 4^ horse-power, with a steam-pressure of 
 100 lbs., the temperature of the feed-water being 1G0° ? 
 
 The equivalent evaporation required per liorse-])ower per hour 
 is 1.1 times 63, or OO-^'u lbs. The total equivalent evaporation is 
 44 times GOi^o, or about 312 lbs. Hence the grate-surface, being 
 the quotient arising from dividing 313 by 78, is 4 square feet. 
 The heating surface is 30 times 4, or 130 square feet. The cross- 
 section of the tubes should be about 0.53G square feet (4 times 
 0.134), or it should vary between the limits of 0.5 (4 times 0.125) 
 and 0.573 (4 times 0.143) square feet. 
 
 While the rules relating to engines given above are generally 
 only applicable for cases within the limits mentioned at thiB be- 
 ginning of this article, those for the proportions of boilers give 
 safe average values for the majority of axses that are met with 
 in practice. B. 
 
 Engines, Derangements of. — These are hot bearings, loose 
 keys, and leaky joints. If a bearing heats continually, when 
 properly adjusted and well lubricated, it is too small. Some- 
 times l)earings heat on account of dirt or grit, becausti they are 
 set up too tightly, or are out of line. A hot bearing can often be 
 cooled without stopping the engine, by mixing sulphur or l)lack- 
 lead with the oil, or by turning on a stream of water from a 
 hose. If a joint blows out it can sometimes be wedged, so tliat 
 the engine can be run until stoj)inng tinu;. An engineer should 
 exercise all liis ingenuity to overcome a (lifRcuI ty without slo])- 
 ping the engine, except in cases where it would Ix^ dangerous to 
 continue to run. If keys or bolts become loose, it will generally 
 be indicated l)y a thump in the engine. To prevent the freezing of 
 pipes and connections in exposed situations, they should either be 
 thoroughly drained, or the water should be kept circulating in 
 them. B. 
 
 Exhaust Steam. — This should not be discharged into a brick 
 chimney. It is liable to disintegrate the mortar and destroy the 
 chimney. 
 
 Steam-EngineGoveknous. — The ordinary ]iendulum governor 
 consists of a vertif-al s))indl<', which is made to revolve by suitable 
 mechanism, and carries, on opposite sides, a pair of arms, to 
 wliii-li licavy weights are attached, forming revolvingpendulunis, 
 whicli vary their ])08itions at dilTerent si)eeds. 'I'he Himj)U'St 
 form of construction is shown in Fig. 1, A B l)eing the revolv- 
 ing spindle, V, and I) tlm weiglits, secured to the spindle l)y rods 
 jointid at (J. Sev<Tal positions of tbe liiills are shown, corn;- 
 sjionding ti) (lilTcirnt spi'eds of rotalion. In any of these jiosi- 
 tions, the verlii ill distanci-, as (J l'\ I'f tlie point of suspension, (i, 
 above tlie centres of tlie i)alls, is called iln- A.////// of the(joveTiioi\ 
 
ENGINKKIUjSTG. 
 
 67 
 
 and it can be found for any case by dividing 33,508 by the 
 square of the number of revolutions per minute. For instance, 
 if a governor naalics 100 revolutions per minute, running with- 
 out friction or other resistance, the vertical distance of the cen- 
 tres of the balls below the point of suspension would be 32,508 
 divided by 10,000 (the square of 100), or about 3i inches. A table 
 i? added, showing- the heights corresponding to various speeds. 
 
 Table. 
 
 Revolutions Height in 
 
 per minute. inches. 
 
 10 352.08 
 
 20 88.02 
 
 30 39.12 
 
 40 22.01 
 
 50 14.08 
 
 60 9.78 
 
 TO 7.184 
 
 80 5.501 
 
 90 4.347 
 
 100 3.521 
 
 125 3.253 
 
 150 1..564 
 
 175 1.150 
 
 200 0.8802 
 
 225 0.6955 
 
 250 0.5G33 
 
 Revolutions Height in 
 
 per minute. inches. 
 
 275 0.4646 
 
 300 0.3912 
 
 350 0.2873 
 
 400 0.2201 
 
 450 0.1739 
 
 500 0.1408 
 
 550 0.1164 
 
 600 0.0978 
 
 650 0.08333 
 
 700 0.07184 
 
 750 0.06259 
 
 800 0.05501 
 
 850 0.04873 
 
 900 0.04347 
 
 950 0.0:)901 
 
 1000 0.03521 
 
68 
 
 ENGINEKKIKG. 
 
 In practice, the pendulum governor is generally constructed 
 somewhat as represented in Fig. 2, being connected to the con- 
 trolling mechanism by f<hort lever.s, so that a slight change in the 
 position of tlie balls will move the regulator considerably. In 
 estimating the height of the balls of such a governor, it is to be 
 measured from E, where the centre lines of the arms produced 
 cut the centre of the spindle. 
 
 When a governor, acts on the controlling mechanism of an en- 
 gine, it encounters some resistance. There is also some friction 
 of the moving parts, and a weight is sometimes added, either 
 sliding on the spindle or connected to the spindk- by a lever, in 
 order to make tlie governor more sensitive. All these things in 
 tiueuce the height of the governor. In a well-made instrument 
 the friction is insignificant, and need not be regarded, but allow- 
 ances must be made lor the resistance, and the weight, if any is 
 attached. Find how numy pounds of force are re(juired to move 
 the controlling meclianism of the engine, and lind the weight 
 
 of the balls and <i( the attached weight, in i)ounds. Next de- 
 termine how far the controlling ineclianism is movt^l, and th(^ 
 attaclu^d weight raised or lowered, for a given change in the 
 height of tlu! governor l)alls. Divide tint (iistanc(! moved l>y the 
 resistance l)y tlu; change in height of the bails in the same time, 
 and multiply the <]Uotient by tlu^ measure of the resistance in 
 ])()unds : dividi' also the vertical distance moved by the attached 
 weight for a iriveii change in the height of tlie balls, and multi- 
 ply tlie (piotient liy this weight. Take tlie sum of these two jiro- 
 ducts and the weight of tlu! governor-balls, and divide liy the 
 weight of tlui governor-l)allH ; multiply t\w (juotiiMit by the lieight 
 ff)r a governor working freely, takc^n from the tabh; above : the 
 (jiiotient is the correctrd lieiij-ht of th(^ governor-balls. 
 
 h\ri//ii />/<■.■ — Tli(i two l);illsof a governor weigh 20 lbs.; the rcisi.s- 
 tance of the iiicchaiiisni is 10 lbs., and it moves l in. wliile the 
 heiifht of the balls chungeH } inch. The attached weight is M lbs., 
 and it moves 2 inches vertically, while tiie lii-ight of the balls 
 ♦•lianges ^ in. What is the heiglit of Imlls for a speed of !200 
 revolutions a mimiteV Multijilyini!: the (piotient of 1 divided by ,| 
 (4) l»y 10, tlie product is 10 ; multiplying the <piotient of 2 divi<l- 
 
ilNGINKKRlNG. 69 
 
 ed bj i (8) 1)V 8, tlie product is 64 ; dividing the sum of 40, 64, 
 and 20 (124) by 20, the quotient is 6.2 ; multiplying 6.2 by 
 0.8802 (the height for a free governor making 200 revolutions a 
 minute), the product, the corrected height of the governor-balls, is 
 about 5^ inches. 
 
 In designing a governor, it is well to fix upon some range of 
 speeds between which it shall control the engine, and make the 
 balls heavy enough to effect this. The proper weight for the 
 balls can be found approximately, as below: 
 
 (1) Divide the distance through which the resistance moves by 
 the change in height of the governor-balls in the same time, and 
 multiply the quotient by the resistance ; divide the vertical dis- 
 tance through which the attached weight moves by the vertical 
 distance moved by the balls in the same time, and miiltiply the 
 quotient by this attached weight ; add together these two pro- 
 ducts, and divide the sum by 2. 
 
 (2) Subtract the mean speed of the governor from the greatest 
 speed it is to have, and divide the difference by the mean speed ; 
 divide the quantity obtained in (1) by this quotient : the result 
 will be the weight of the two balls. 
 
 Example. — Suppose the resistance and attached weight are the 
 same as in the preceding example, and that the speed of the 
 governor is to vary between 200 and 300 revolutions a minute, in 
 controlling the speed of the engine. What should be the weight 
 of the balls? 
 
 (1) The sum of 40 and 64 (the corrected resistance and attached 
 weight) is 104 ; 4- of 104 is 52. 
 
 (2) The difference between 300 and 200 (100), divided by 200, is 
 0.5 ; the quotient of 52 divided by 0.5, or the weight of the balls, 
 is 104 lbs., so that each ball must weigh 52 lbs. B. 
 
 Horse-power, Different kinds of. — In making an estimate or 
 measure of the effect of any piece of mechanism that is used to 
 overcome resistance, it is necessary to have a unit of reference. 
 In whatever manner the resistance is overcome, if it can be mea- 
 sured it can be converted into the amount of work that must be 
 expended to raise a weight through a distance, since by suitable 
 arrangements the mechanism can be put in motion and made to 
 overcome resistance by allowing the weight to fall. This gives a 
 simple mode of estimating the work, by assuming that a unit of 
 \«ork is the amount required to raise 1 pound a distance of 1 foot 
 vertically. To illustrate, suppose that a cut is being taken from a 
 6-in. shaft in a lathe, and that the resistance to the motion of the 
 cutting-tool is 200 lbs.; how many units of work are performed 
 each time the shaft makes a revolution ? 
 
 In each revolution of the shaft, the tool makes a cut 6 times 
 3.1416, or 18.8496 ins., or 1.5708 ft. in length, and the work is 
 the same as would be required to raise a weight of 200 lbs. 
 through ;i vertical distance of 1.5708 ft., or it is 314.16 units. 
 
 Now, if :!3,000 units of work are performed in a minute, they 
 constitute a unit of power, known as a horse-power' — and con- 
 versely, a horsepower can be defined as the power required to 
 raise 33,000 lV)s. 1 ft. high, or do 33,000 units of work in a 
 minute. Again, a horse-power may be defined as the power re- 
 quired to perform 550 units of work in a second, or 1,980,000 
 
70 EXGIXEERING. 
 
 units in an hour. To apply the principle to the example given 
 above, suppose the shaft makes 20 revolutions a minute, how 
 many horse-power are required to drive the t(jol ? In this case, 
 the units of work performed per minute would be 20 times 
 314.16, or 6383.2, and the horse-power would be ^htWd of 6283.2, or 
 about ju'g of a horse-power. It will be seen, from this e ample, 
 that if the resistance to motion in pounds and the speed of motion 
 in feet per minute can be measured, it is only necessary to multi- 
 ply them together, and divide by 33,000, in order to obtain the 
 horse-power. The steam-engine is a uiachine that is commonly 
 rated as being of a certain horse-power, but the term horsepower, 
 as thus used, does not always have the same meaning. In fact, 
 there are four kinds of horse-power by which an engine may be 
 rated : 
 
 1. Gross or indicated horse-power. 
 
 2. N'et or effectim " 
 
 3. Total 
 
 4. Nominal 
 
 1. Tiie gross or indicated horse-power of an engine is the power 
 calculated by assuming tiie resistance to be that due to the mean 
 effective pressure of the steam on the piston, as shown by the in- 
 dicator. Thus, suppose this pressure is 3500 lbs., and the piston 
 moves 400 ft. a minute, the gross horse-power is 400 times 3500 
 divided by 33,000, or 30.3. 
 
 2. The net or effective horse-power of an engine is computed 
 from the useful resistance overcome. If, in the preceding exam- 
 ple, the pressure on the piston, after deducting that required to 
 overcome the friction of the engine, is 2200 lbs., the effective 
 horse-power is 3300 times 400, divided by 33,000, or 36.7. 
 
 The net horse-power is the proper kind to be specified by a 
 steam-user when he is buying an engine. 
 
 3. The total horse-power of an engine is computed from the to- 
 tal pressure on the piston above a vacuum. If, in the example 
 given in Case 1, the total pressure on the piston is 4200 lbs., the 
 total horse-power is 400 times 4200, divided by 33,000, or 50.9. 
 
 Total horse-power is only used in comparisons of the results of 
 experiments. 
 
 4. The nominal horse-power of an engine has no mi'uning in 
 particular — that is to say, there are a number of different rules 
 by which it may be computed. Tiius, there is tlie admiralty ruli^ 
 for nuirine engines, Mr. Bourne's rule for condensing engines, 
 -Mr. Bourne's rule for non-condensing engines, James Watt's ruli^ ; 
 and numi'xous engine-builders have private rules of tlieir own. 
 For instance, ^1 says, " I will make an engine with a cylinder 10 
 ins. in diameter, and a stroke of 15 ins., and I will call it 8 
 liorse-power, nomiiuil." 
 
 li, who l)uil(ls an engine of the same size, and wants to nuike 
 purcluisrrs tiiiidv tlicy are getting more for their money, says, 
 " I will call my engine l(i liorse-])ower, nominal." The man who 
 jfoes to buy a steam-engino of either of these j)arties may very 
 properly say to tliem, " How much will you charge me for an 
 engini- guaranteed to be of so nuiiiy horse iK)Wi'r, aitual ?" B. 
 
 Im)KAT(»1{, The steam-engine. — The construction is shown in 
 Figs. 1 and 2, Fig. 1 being an elevation, and Fig. 3 a section. 
 
 1 
 
ENGINEERING. 
 
 71 
 
 The iudicator is a recording steam-gauge, very accurately made, 
 for determining the pressure acting on the piston of an engine, 
 at every point of the stroke. It is connected to the cylinder, 
 close to one end, and wlien the cock, seen in Fig. 1, is opened, 
 the steam presses on a small piston, shown in Fig. 2. A stifE 
 spiral spring above this piston is compressed by the pressure of 
 the steam. The piston-rod, it will be seen, is connected to a 
 lever, and this, in turn, with a: link and another lever, a pencil or 
 marking-point being placed in a hole in the link. There is a 
 cylindrical barrel to the left on which a piece of paper can be 
 placed, being held by two clip springs. This barrel can be made 
 to revolve by pulling a string wound round the bottom, and it 
 has within it a coiled spring, which makes it turn back again 
 
 Fig. 1. 
 
 the indicator. 
 
 Fig. 2. 
 
 when the tension of the string is relaxed. Now, suppose that the 
 indicator is attached to the cylinder of an engine, and the cord is 
 fastened to some moving part, so that when the engine makes a 
 stroke it causes the barrel carrying the paper to revolve, and on 
 the return stroke the coiled spring in this paper barrel makes it 
 turn back to its original position. Meanwhile the steam in the 
 cylinder is pressing on the piston of the indicator, forcing it up 
 a distance corresponding to the pressure, so that if the pencil is 
 allowed to touch the paper, it will trace out a line which repre- 
 sents the pressure, and this line is called an indicator diagram. 
 Such a diagram is shown in Fig. 7. The atmospheric line, C D, 
 
V2 
 
 ENGINEERING. 
 
 is traced when the cock is closed and there is no pressure on the 
 piston. At b, the stroke of the engine commences, and when the 
 piston has gone about half way to the other end of the cylinder, 
 the steam is cut off, as shown at c, and the pressure begins to fall 
 as the steam expands. Near the end of the stroke, the exhaust- 
 valve opens, as shown at d, and the pressure falls more rapidly. 
 When the engine makes the return stroke, there is only the back 
 pressure^ until near the end, when the exhaust-valve closes, 
 shown at /, and the steam being compressed, the pressure rises. 
 Just before the end of the stroke, at a, on the diagram, steam is 
 admitted, and the pressure rises suddenly. 
 
 I. How to attach the indicator to the ryliader of an engine. . 
 Drill a hole in the cylinder, in the head, or close to the end, 
 
 and tap it out for a half-inch iron nipple. The indicator-cock 
 must be connected to this, using an elbow, if necessary, and then 
 the indicator can be attached at pleasure. In drilling this hole, 
 do not make it close to the ports. Sometimes the connections 
 from the two ends of a cylinder are brought together, and one 
 indicator is made to answer for both ends, a cock being fitted in 
 each pipe, so that either can be opened to the indicator, as desired. 
 In such a case, the holes in the cylinder should be larger, for 
 three-quarter inch pipe, at least, so as to prevent any loss of pres- 
 sure. It is obvious, however, that as the indicator is used to ob- 
 tain the pressure in a cylinder, the more closely and directly it is 
 connected, the better. 
 
 II. IIoic to make the paper barrel have a motion coincident with 
 that of the pidon. 
 
 a. Rednciny-iclieel. — Fig. 3. 
 
 J^e:^.J 
 
 This is attached to some part of tlie ongino-rramo, and the cord 
 marked " to euirino" is mnde fast to tlw crnsshead, being carried 
 over a pulley, if necessary, so tluit it is parallel to the guides, 'i'he 
 other cord is fastened to the cord wound round tlie paper barrel of 
 the indicator. Tlie two whci-ls bi-ar the siinic j)ro]iortion to each 
 r)tlif'r as the stroke of Ihr enginr does to thr (iesired range of 
 motion for tlie paper barrel, tlie latter being usually from 4 to 
 
ENGINEERING. 
 
 73 
 
 5 iuches. There is a coiled spring in the reducing-wheel, which 
 makes it turn back on the return movement of tlie cross-head. 
 By having different sized wheels to carry the cord leading to the 
 indicator, this arrangement can be adapted to engines with dif- 
 ferent strokes. 
 b. Swinging -board, with slot. — Fig. 4. 
 
 Mark a point, A, at some convenient distance from the cross- 
 head, and on a line perpendicular to the guides, at the centre of 
 the stroke. Attach a board so that it can swing freely around 
 this point ; cut a slot in the other end, for a pin connected to the 
 cross-head. Then, as the cross-head moves, it will make the 
 board swing to and fro. At some point B, of the board , which 
 
 has the proper movement for the paper cylinder, attach a cord or 
 wire, and carry it over a pulley, C, adjusted at such a height that 
 the part of the cord, B C, is parallel to the guides when the en- 
 gine is at half stroke. The cord can then be brought down and 
 attached to the cord of the paper barrel. 
 
74 ENGINEERING. 
 
 c. Smnging-boqrd, tcith link. — Fig. 5. 
 
 Sometimes it is uot practicable to attach the board directly to 
 the cross-head by a piu, aud it is more coiiveuient to use a liuk 
 connection, the arrangement of which will be evident from the 
 figure. 
 
 It is easy to see that a number of arrangements could be de- 
 vised on the general principle of the swinging-board. Sometimes 
 it is attached to the guides by a standard, and sometimes one end 
 is connected to the cross-head and the other to the indicator, the 
 point aroaud which the board swings being between, at distances 
 from the two ends proportional to the stroke of the engine and the 
 movement of the paper barrel. Whatever the special arrange- 
 ment, attention should be given to these two points : 
 
 \st. To have the hoard perpendicular to the guides wJien tlie en- 
 gine is at half stroke. 
 
 2d. To lead tlie cord off in a direction parallel to the guides. 
 
 III. How to take an indicator diagram. 
 
 If a cord is used for the motion, it should have a slide on it, so 
 that it can be adjusted, and it should have a hook so that it can 
 be attached to the cord of the paper barrel, and detached at 
 pleasure. Fine wire is better than cord, as it is quite flexible, 
 and does not stretch so readily. If several cards, taken at inter- 
 vals, are of the same length, the connection is all right. Having 
 got the motion properly adjusted, turn the cock of the indicator 
 so that it will blow through, having first put a piece of paper on 
 the paper barrel. Then turn the cock so as to let steam into the 
 indicator, and press the pencil lightly against the paper ; draw it 
 back as soon as the card is traced, shut the indicalor-cock, and 
 apply the pencil again, to trace the atmospheric line — be par- 
 ticular not to trace the atmospheric line until the diagram is 
 taken ; then unhook the cord, remove the diagram from the 
 paper cyliniU'r, and mark on it the pressure of steam by gauge, 
 the revolutions per minute, the height of the barometer, and the 
 temperature of the engine-room — if the proper instruments are 
 available — and the vacuum by gauge, the temjierature of the 
 liot-weli, and the temperature of the injection-water, if the dia- 
 gram has Ix'cn taken from a condensingcngine. All the dimen- 
 sions of the engine should also i)e noted, for future reference, to- 
 gether with such particulars in regard to the dimensions and per- 
 formance of th(! boiler as can be obtained. 
 
 A counter should alwavs be enii)loyed to detennine the number 
 of revolutions ])er minute, at tlie time the diagram is taken. It 
 can be connected to the indicator motion, or to souu^ moving part 
 of the engine. Take its reading at the beginning of a minute, 
 and at the end, having indicated the engine meanwhile. This 
 gives the revolutions at tlie time the card was taken, with consid- 
 erable accuracy. 
 
 IV. Ifinr to draw the true dittr/ram. — Fig. 0. 
 
 Tlie indicator diagram from oik; end of tlu; cylinder, it is evi- 
 dent, only shows wlutt takes ])lace on the side <if the ])iston on 
 wliich till- indicator is applied— but at the same time tliere is 
 some hiuk pressure on the other side, opposing the motion of tlie 
 
ENGliSrEERING. 
 
 V5 
 
 piston. To get the actual diagram, therefore, it is necessary to 
 take diagrams from both ends of the cylinder simultaneously, and 
 then combine the parts of each that were traced at the same time. 
 Thus such a figure as is shown in Fig. 6 is obtained. On one 
 side of the piston, the line a b c f is traced, and d c eis traced at 
 
 a 
 
 ^£^.^' 
 
 the same time on the other, and the figure so obtained is the trite 
 diagram representing the distribution of the pressure. In using 
 the diagram as ordinarily taken, therefore, the actual effective 
 pressure is not obtained ; but there is no error in practice, since 
 the inaccuracies of the diagrams from the two sides balance each 
 other. It is a great mistake, however, to take diagrams from one 
 end of a cylinder only, and assume that those from the other 
 would be similar. Quite often there are serious differences, and 
 both ends of a cylinder should always be indicated, if possible 
 
 V. Ho\o to ascertain the mean effective pressure from a diagram. 
 —Fig. 7. 
 
 a. 1st method.— T>v&vf perpendiculars to the atmospheric 
 line, from the extremities of the diagram, thus determining 
 its length, C D ; divide the line, (J D, into 10 equal parts, 
 and midway between each of the divisions erect a perpendicular 
 to C D, drawing it between the upper and lower boundaries of 
 the diagram ; measure the length of each of these lines on the 
 scale of the indicator-spring, add the measurements together, 
 and divide the sum by 10. In the figure, the pressure, or length 
 
76 
 
 ENGINEERING. 
 
 of the line on the scale, is shown at each perpendicular. The 
 sum of these is 363, so that the mean effective pressure is 36.3 
 lbs. per square inch. 
 
 b. 2d method. — Draw perpendiculars between the ten divisions 
 of G D, as explained above. Then take a strip of paper, apply 
 it to the first perpendicular, and mark the length ; apply it to the 
 next perpendicular, and mark its length, next to the first ; so 
 continue applying it to each, and when the last perpendicular has 
 been measured, the distance between the first and last marks will 
 be the sum of all the lengths. The strip of paper. A D, is shown 
 in the figure as applied to the third perpendicular. Measure the 
 length of the paper between the extreme marks, in inches, multi- 
 ply it by the scale of the indicator-spring, and divide by 10. Sup- 
 pose, in the present case, that the length of the paper is found to 
 be 13.1 inches, and that each inch represents 30 lbs. on the scale 
 of the indicator-spring ; 30 times 13.1 is 363, so that the mean 
 effective pressure is 36.3 lbs. per square inch, as before. 
 
 c. Positive ami ntyatice pressure. — Fig. 8. 
 
 When the steam is cut off very early in the stroke, and the 
 valves and piston are tight, a diagram is sometimes drawn 
 like that in the figure, iu which the back pressure is greater than 
 the forward j)ressure for a ])ortion of llu' stroke, and the pressure 
 determined from the ])f)rtion of the diagram a r b must be sub- 
 tracted from tli(! jiressure due to the portion d e n f. In such a 
 case, the method of determining the mean pressure is as follows : 
 Divide tlie atmosjiheric line into 10 equal parts, as before, and 
 draw i)erpendiculars midway between them ; add togetlier the 
 j)erpendiculars (mea.surc'd in the scale of the indicator-sjtring) in 
 th(i positive |)art of the diagram, also those in the negative jiart ; 
 subtract tln^ latter from the first sum, and divide tin- difft^rence by 
 10. In the. figure, Ww, pressures at the different ))er|)endiculars are 
 jriven. The sum of tln^ i)ositiv<' jjre.^siires is 179, of the nei^ative 
 pressures 35, and the difference is l.')4 ; ho that tlie mean effective 
 pressure is 15.4 lbs. jxt wpiare inch. 
 
 W. If "in to find the indicated horse-poiner of a steam-engine. 
 
 Having dctciniinrd tlic mean effective pressure from » diiigram, 
 l)y one of tlie methods explaiiK-d abovi;, multiply this pressurt; by 
 tlie product of the stroke in feet, the square of the diameter of 
 
ENGINEEKING. 
 
 77 
 
 the cylinder in inches, the number of revolutions per minute, and 
 0.0000476. 
 
 Example. — Suppose the mean effective pressure is 50 lbs. per 
 square inch, the diameter of the cylinder 15 inches, the length of 
 stroke 2 feet, and the number of revolutions per minute 80. 
 Then the horse-power is the product of 50,225 (the square of 15), 
 80, and 0.0000476, or 85.68. 
 
 VII. How to construct the theoretical diagram. — Fig. 9. 
 
 J^f'^. ^. 
 
 This is the diagram that would be taken if the steam acted in 
 the cylinder with the pressure at the beginning of the stroke un- 
 til the point of cut-off, and that then the admission ceased instan- 
 taneously, and the steam expanded, in accordance with Mariotte's 
 law, to the end of the stroke, when the exhaust-valve opened, and 
 the steam was immediately condensed, creating a perfect vacuum 
 in the cylinder for the return stroke. Such a diagram is repre- 
 sented hj A B C D E, this being the theoretical diagram for the 
 actual diagram, a b c d e. The following is the method of laying 
 it down: Draw a line, E D, a.t a distance below the atmospheric 
 line, n d, equal to the pressure of the atmosphere (14.7 lbs. per 
 square inch on an average), on the scale of the diagram ; mark 
 on E D the length, o D, of tlie actual diagram ; then find the to- 
 tal volume of the clearance spaces at the end of the cylinder from 
 which the diagram was taken, and make o E bear the same rela- 
 tion to D as this volume of clearance has to the total volume 
 swept through by the piston per stroke. To make this plaiii, sup- 
 pose that in a cylinder having a diameter of 24 inches and a stroke 
 of 3 feet, it is found that the volume of the clearance spaces at one 
 end of the cylinder is 900 cubic inches. The volume swept through 
 by the piston per stroke is the product of 0.7854, 24 squared, and 
 36 or 17,286 cubic inches, so that the clearance is about y^-g-jy of tlie 
 piston displacement, and o E must be made toot as long as o D. 
 Thus, if D is 5 inches, o E must be -,"o% oi an inch. Having de- 
 termined the point E, make E A perpendicular to ED, and draw 
 a line, A B, parallel to ED, at such a height that it represents 
 the initial pressure of the steam. Through c, on the actual dia- 
 
78 ENGINEERING. 
 
 gram, where tlie steam is cut off, draw a perpendicular, B H, to 
 ED. Divide ED into any number of equal parts, and erect per- 
 pendiculars at the points of division that are l)eyond the point of 
 cut-ofF. From E draw any diagonal line, E F, and from E as a 
 centre, with a radius E II, draw an arc cutting E F in the point 
 G. From the same centre, and with radii equal to E A, E 5, etc., 
 draw arcs cutting E F. The arc drawn with a radius E 4, cuts 
 E Fin the point /. Draw the line f A, and from G draw a line, 
 G ff, parallel to /A. From g draw a line, </ /i, parallel to f A, 
 and the point 7i, in which it cuts the perpendicular drawn through 
 4, is a point of the curve of expansion. The construction of the 
 points on the other perpendiculars is i:)recisely similar, and is in- 
 dicated in the figure. Having determined a sufficient number of 
 points, draw through them the curve of expansion, B h i k I in C, 
 and the theoretical diagram will be completed. 
 
 This kind of diagram is useful for comparing the merits of dif- 
 fei'ent engines, since it is evident that, other things being ecjual, 
 the engine whose actual diagram most closely approaches the 
 theoretical is the best. The mean i)ressure, as shown by such a 
 diagram, can be determined by one of the methods already ex- 
 plained, for ctmiparison with the pressure given by the actual 
 diagram. 
 
 VIII. IIotD to take care of the indicator. — Al ways oil the cylinder 
 and all moving parts before api)]ying the instrument to an engine. 
 Never use any thing l)ut the finest grade of oil, such as that 
 specially ])repare(l for sewing-macliines or clocks. After taking 
 oiu! or two diagrams, remove the intlicator, and examine its steam- 
 cylinder. If any grit has entered, wijje it out, using soft cotton- 
 waste on the end of a white-pine slick. It is important to attend to 
 this on indicating an engine of which the condition is not known, 
 and if it is found tluit dirt or grit is forced into the indicator, it 
 should b(^ cleaned at frcciuent intervals during the experiments. 
 As soon as tlie experiments have been concluded, remove tlu^ indi- 
 cator, and when it has cooled sufficiently, wipe it out and ai)i)ly 
 oil in the steam cylinder, and to all the moving parts. Be careful 
 to dry till! si)ring thoroughly, and cover it with f)il. Never put 
 any liard sui)stance into tlu; steam-cyrnidcr. but use a whit('-i)ine 
 Stick and soft cotton-waste. After u.se, take out tin* ])lug of the 
 indicator-cock, clean it and the seat, ajjjjly oil, and on rei)lacing it 
 adjust it so that it moves f redely and does not leak. 
 
 It might be supposed that minute directions of this kind were 
 suiHTfhious, and tliat any one owning an indicator would see tlie 
 necessity of using su(;h a delicate instrument with great care. 
 The generality of the indicators in common use, however, ini- 
 presB the observer with the idea that all the directions recittnl 
 al)ove liavf- been studiously neglected B. 
 
 Sr,Ti)K-VAT,VK8, Setting. — The methods of adjusting the lap 
 ;ind travel of slidcsvalves, and tlw jiositioii of the ecci-ntric, given 
 itel(»w, are taken, with some slight modifications, from the work 
 of Dr. Zenner, on Siide-Valve (Jeuring. It is IxOieved that the 
 sinijilicity of the construction will be appreciated by th(! reader. 
 
ENGINEERING. 
 
 79 
 
 I. Area of ports. — To find ilie proper area of port for a,n en- 
 gine of a given piston-speed, multiply tlie area of the piston, 
 
 -fc^ 
 
 
 SETTINS THE SLIDE-VALVE, 
 
 in square inches, by the number nearest to the given piston-speed 
 in the table on the next page. 
 
80 ENGINKEIUNG. 
 
 Speed of piston, in feet, Number by which area of piston 
 
 per minute. is to be multiplied. 
 
 lUO 0.02 
 
 200 0.04 
 
 300 0.06 
 
 400 0.07 
 
 500 0.09 
 
 600 0.1 
 
 700 0.12 
 
 800 0.14 
 
 900 0.15 
 
 1000 0.17 
 
 1100 0.19 
 
 1200 0.2 
 
 1300 0.22 
 
 1400 0.24 
 
 1500 0.25 
 
 II. Lap, lead, and travel of valve. — The amount of opening 
 given by the valve for the admission of steam or its exhaust, at 
 the commencement or termination, respectively, of the stroke of 
 an engine, is called the lead, either steam or exhaust, as the case 
 may be. If tlie face of tlie valve is wider than the port, the ex- 
 cess of width is called lap, and may be either steam or exhaust 
 lap. Steiim-lap is an excess of widtli on the outer extremities of 
 the valve-faces, and exhaust-lap an excess on the inner fac,es. 
 The effect of steam lap is to cut off the steam at an earlier point 
 of the stroke, and exhaust-lap causes the exhaust to open later 
 and close earlier than it otherwise would. It must be obvious 
 that the action of the exhaust would be very much deranged if 
 an attempt was made to cut off very short, and it is found, in 
 practice, that tin; limiting ])oint of cut-off with the simple slide- 
 valve is at about two thirds of the stroke. 
 
 The travel of the valve is the distance between its two extreme 
 positions. For a valve without lap or lead, the travel is equal to 
 twice the width of the? steam-])ort. If lap is added, tlie travel of 
 tlie valve is equal to twice the width of the port, increased by 
 twice th(! amount of steam-lap on one end. 
 
 III. The crcriilnc. — The eccentric, which moves the valve, is a 
 substitute for the crank, and consists of a circular disk secun^d to 
 the shaft, the centre of the disk lying outside of the centre of the 
 sliaft. The diKtance between the centres of the eccentric and the 
 shaft is e(jual to half the travel of the valve. If a valve has 
 neither lap nor l<;jid, tlu^ eccentric is secured to the shaft in such 
 a position that a line joining its centn^ with the centrtM)f a shaft 
 is perpendicular to a line connecting the centre of the shaft and 
 the, c(!ntre of the craid^-])in. If the valves has h^ad, the eccentric 
 must b<! turned on the shaft suflicieiitly to secun; the desired 
 iiiiiount, and if lap is also added to the steam side, the eccentric 
 must b(^ advanced still further. In either of these cases, the 
 amount the (iccentric is moved forward is termed the angular ad- 
 vances of the (jccentric, l)eing the angle niadc; by a line joining 
 the centres of the eccentric and shaft with a lint! drawn tiirough 
 the centre of the sliafi perpeniiiciihir to the line of centres of the 
 
ENGINEERING. 81 
 
 crank-pin and shaft. The points in which these two perpendicu- 
 lar lines intersect the shaft should be plainly marked by a 
 centre-punch or chisel, for convenience in adjusting the eccentric. 
 
 IV. Proportions of valve and .teat. — The bridge of the valve- 
 seat sliould generally have a width equal to the thickness of the 
 cylinder. The width of the exhaust-port is found by adding the 
 width of the steam-port to the half-travel of the valve, and sub- 
 tracting the width of the bridge. 
 
 The length of the valve is equal to the width of the exhaust- 
 port, increased by the width of the bridges and the two faces. 
 
 V. To find the lap and travel of the valve, and angular ad- 
 vance of the eccentric, for given points of admission, cut-off, and 
 release. — Draw a horizontal line, A B, and lay off on it, any dis- 
 tance, A C, to represent the length of stroke of the engine. Make 
 E S equal to the length of the conuecting-rod between centres, 
 and S D equal to one half of A C. With 2) as a centre, and D 8 
 as a radius, describe a circle, which represents the path described 
 by the centre of the crank-pin. The arrow shows the assumed 
 direction of the motion of the engine. Assume some point, E, at 
 which it is desired to have the steam-valve beyin to open when 
 the piston has still to complete the portion E A oi its return 
 stroke. Assume also a point, F, at which the steam is to be cut 
 off when the piston has advanced a distance, E F, and a point, Q, 
 at which the exhaust-valve is to be begin to open when the pis- 
 ton has completed the portion E O oi the stroke. Then, with 
 each of these points, E, F, G, as a centre, and with the length of 
 connecting-rod, ^ «S, as a radius, describe an arc of a circle cut- 
 ting the path of the crank-pin in the three points e, f, g. Join 
 each of these points with the point D, thus determining the po- 
 sition, D e, of the crank at the instant of admission, its position, 
 D f, at the instant of cut-off, and its position, D g, at the instant 
 of release. Bisect the angle e D fbj a straight line, D L ; make 
 D Lot any convenient length, and upon it, as a diameter, describe 
 a circle, and note the point, M, in which it cuts D e. From D as 
 a centre, and with D 31 us a radius, describe an arc of a circle, 
 MB N. Measure the lengths of the lines B 31 and B L, and 
 divide the former by the latter. Subtract the quotient from 1, and 
 di\'ide the width of steam-port by the difference. This gives the 
 travel of the valve. Multiply the travel of the valve by half the 
 quotient obtained above, and the product will be the steam-lap. 
 The angle L B I is the angular advance of the eccentric. Di- 
 vide the length of S R by the length of L B, and multiply half 
 the quotient by the travel of the valve : the product is the steam- 
 lead. 
 
 Next produce the line L B, making B equal to B L, and 
 upon Z) 0, as a diameter, describe a circle, noting the point, P, in 
 which it cuts B g, the position of the crank at the instant of re- 
 lease. Divide the length of Z) P by the length of B 0, and 
 multiply half the quotient by the travel of the valve, which gives 
 the exhaust-lap. With Z) as a centre, and i> P as a radius, de- 
 scribe an arc, P T Q, noting the points, T and Q, in which it cuts 
 A B, and the circle whose diameter is B 0. Divide the length of 
 T Why the length of B 0. and multiply half the quotient by the 
 travel of the valve : the product is the exhaust-lead. Through the 
 
82 ENGINEERIlSrG. 
 
 point Q draw the line Z) // : tliis is the position of the crank at 
 the instant the exliaust-valve closes and cushion commences. 
 With h as a centre, and A S, the length of the connecting-rod, 
 as a radius, describe an arc cutting the line A B in the point H ; 
 tlieu G II is the portion of the return stroke completed when the 
 exhaust-valve closes. 
 
 On account of the angularity of the connecting-rod, the points 
 of cut-off and exhaust closure will vary somewhat on the re- 
 turn stroke. They can be equalized by a slight change in the an- 
 gular advance and length of the eccentric rod. 
 
 VI. Exiimple. — The following example will serve to illustrate 
 the application of the preceding principles : 
 
 A valve is to be designed for an engine having a cylinder 20 
 inches in diameter, and a stroke of 2i feet, making 80 revolutions a 
 minute. The length of the connecting-rod is 6^ feet. The valve 
 is to admit steam when the piston has made 0.997 of the stroke, 
 is to close the steam-port at two thirds of the stroke, and open 
 the exhaust when /'(fn of the stroke has been completed. 
 
 The area of the i)iston, in s<iuare inches, is 0.7854 times 400 
 (the square of 20), or 314.16, and the piston-speed is 400 feet per 
 minute ; hence the proper port area is 0.07 times 314.16, or about 
 22 square inches. Assuming the length of the port to be ecjual 
 to the dianieter of the cylinder, 20 inches, its width will be ./,, of 22, 
 or 1.1 inches. The width of the bridge must be equal to the thick- 
 ness of the cylinder, or \\ inclies. In tlie figure, make J57iS' equal to 
 2i times A 'C, and E A, 0.997 of A G, A F,io{ A G, and A G, 
 0.95 of A G. Constructing the positions of the crank corre- 
 sponding to these jioiiits of stroke, and making tli(^ other con- 
 structions as explained above, suppose that the data obtained 
 from the figure l)v measurement are as follows : 
 
 Angle li D M, 5^ ; angle M D jST, 108|' ; angle R U P, 
 151^° ; angle T D Q, 137|-^ ; angle L D I, an(pilar advance of 
 ecrcntric, 40^^° ; 7) M, 0.65 of an inch ; I) L and D 0, each 1.5 inches; 
 D P, 0.19 of an inch ; SB, 0.1 of an inch ; T W, 0.375 of an inch ; 
 (' II, part of return stroke eomplet<d when exhaust closes, O.S~). 
 Dividing D M (0.65) by D L (1.5), the quotient is 0.43+ ; sub- 
 tracting 0.43 from 1, the remainder is 0.57 ; dividing twice the 
 width of steam-])ort, 2.2, by 0.57, the quotient, the travel of the 
 vali)e, is 3.80 inches. Multiplying * of 0.43 bv 3.80, the product, the 
 steam-lap, is 0.83 of an inch. Dividing I) /''(O 19) by D O (1 .5). the 
 quotient is 0.127 ; multiplying \ of 0. 127 by :!.S6, \\\v. ])r<)<luct, the 
 e.r.haiist-lap,\n 0.25 of an inch. Dividing N 11 (0.1) by 1.5, the quo- 
 tient is 0.007 ; multiplving \ of 0.067 bv 3.S6, the product, the 
 steam-lead, is 0.1 3 of an inch. Dividing" 7' 1^(0.375) by 1.5, the 
 ([uotient is 0.25 ; multiplying A of 0.25 by 3.H6, the jiroduct, the 
 exhaust-lead, is 0.4H of an incli. Adding the half-travel of the 
 valve (1.93) to thr; width of the stcain-ixiH , 1.1, the sum is 3.03 ; 
 Hui)tracting the width of the bridge (1.125), th(^ remainder, the 
 width of the exhaust-port, is 1.91 in. TIks sum of the steam lap 
 (0H3), the exhaust-laj) (0.25), and tlie width of the st,eam-i)()rt (1.1), 
 thelinijth of the ralee-faee, iB2. IH inches. The sum of twice the 
 length' of "face (1.3,6), twice the width of bridge (2.25), and the 
 width of the exhaust-port ( 1.91 ), the leiajthofthe ralre, is 8.52 iiichcs. 
 In this trxaniple no attempt has I)im'ii made to secure great accu- 
 racy, and, as the measurements were made from a small sketch, 
 
ENGINEERING. 83 
 
 tliere may be considerable errors. lu practice, a scale reading to 
 hundredths of an inch should be used, and the figure should be 
 constructed of full size, if possible. This can generally be done 
 by laying down the positions of the crank in a small sketch, and 
 then transferring them to a large drawing ; or the positions may 
 either be calculated or taken from a crank-table, if one is avail- 
 able. By making the drawing full size, and having marks on the 
 shaft as described above, a template can be constructed from the 
 drawing, for transferring the position of the eccentric to the 
 shaft. It may be remarked, that however carefully the valve is 
 proportioned and the adjustment of the eccentric effected, the en- 
 gineer who desires to be certain that the valve-motion of his en- 
 gine is properly arranged, will make the final test and adjust- 
 ments with the aid of the steam-engine indicator. B. 
 
 Testing Small, Engestes. — The apparatus needed is quite sim- 
 ple, and can be readily constructed by the young mechanic. The 
 following embrace the principal points that are generally of in- 
 terest in regard to engines and boilers : Diameter of cylinder, 
 length of stroke, diameters of piston-rod, connecting-rod, crank- 
 pin, valve-stem, fly-wheel, and shaft ; lengths of connecting-rod 
 and crank-pin, weights of whole engine and of fly-wheel, size of 
 ports, stroke of valve, point at which steam is cut off, number of 
 revolutions per minute, clearance at each end of cylinder, pres- 
 sure of steam in boiler, dimensions and weight of boiler, diame- 
 ters of steam-pipe and safety-valve, number of pounds of water 
 evaporated, fuel burned per hour, and power of the engine. 
 Many of these data are obtained at once, by direct measurement 
 or weight. The diameter of the cylinder should be measured 
 when it is at the temperature at which it is ordinarily maintained 
 while running. The point of cut-off can generally be ascertained 
 by removing the cover of the valve-chest, and observing the point 
 at which the steam-valve closes when the engine is moved by 
 hand. This should be done when the parts are heated. The 
 clearance at each end of the cylinder includes not only the space 
 between the piston and cylinder-head at the end of the stroke, 
 but also the volume of the ports. A simple and accurate manner 
 of measuring the clearance is to fill the cylinder with water, 
 when the piston is at one end of the stroke, and then measure the 
 water carefully in a cylindrical or rectangular vessel. The dif- 
 ference between the volume of the water and the volume of pis- 
 ton displacement (area of piston multiplied by length of stroke) 
 will be the clearance. In measuring the piston displacement at 
 the front end of the cylinder, the volume of the piston-rod (area 
 of section of rod multiplied by length of stroke) must, of course, 
 be deducted. 
 
 The number of revolutions of the engine per minute can be de- 
 termined approximately by observation ; but errors are apt to re- 
 sult, especially in the case of small engines moving at a high 
 rate of speed. Small shaft-counters can be obtained at a very 
 reasona-ble price, and measurements made with them are far 
 , more likely to be accurate. 
 
 Many small boilers are not provided with steam-gauges, so that 
 the pressure of the steam can not be observed directly ; but all 
 such boilers have, or should have, safety-valves, and the pressure 
 of the steam can be determined from them. Secure the valve- 
 
84 ENGINEERING. 
 
 stem of the safety-valve to the lever with wire or string, and at- 
 tach a loop to the lever, into which pass the hook of an accurate 
 spring-balance, arranging the loop so that it is directly over the 
 centre of the valve-stem. Then take hold of the upper part of 
 the spring-balance, and lift the valve slightly, noting the reading 
 of the balance. Measure the lower diameter of the safety-valve, 
 and find its area ; divide the reading of the spring-balance by the 
 area of the valve, and the result will be the pressure, in pounds 
 per square inch, at which the steam will raise the safety-valve. 
 Suppose, for instance, that the diameter of the safety-valve is 1 
 inch ; its area will be about fiftn^ of an inch. Now, if the ten- 
 sion of the spring-balance in raising the valve is 120 lb.s., the 
 pressure at wliicli the valve will rise is the quotient arising from 
 dividing 120 by ]Vi/(hi. or 153 lbs. per square inch. It will be 
 easy to make a table for any particular case, giving the pressure 
 corresponding to each pound or fraction of a pound of tension in 
 the balance ; and by calculating in advance the reading of the 
 balance for any given pressure, the weight can be adjusted on 
 the lever until that tension is obtained, and the valve can thus be 
 graduated to lift at anj' reijuired pressure. Having determined 
 the pressure at which the safety-valve will rise when the boiler 
 is cold, raise the valve by means of the balance, from time to 
 time, when the engine is working, and observe the tension. 
 Find the pressure corresponding to this tension, and subtract it 
 from the pressure at which the valve will be raised by the steam. 
 The difference is the pressure in the boiler at the time. For ex- 
 ample, suppose that in the last case the tension of the balance, 
 on raising the valve when the engine was working, was 50 lbs. 
 The pressure corresponding to this will be 50 divided by r",fo%, or 
 about 04 lbs., so that tlie pressure in the boiler at the time 
 would be the difference between 158 and 04, or 8!) lbs. j)er sijuare 
 inch. By preparing a table showing the pressure in the boiler 
 due to each pound of tension in the spring balance, the pressure 
 at any time can be read off as soon as the indication of the balance 
 is observed. 
 
 The amount of water evaporated per hour and the fuel burned 
 can, of course, be readily determined by measurement, drawing 
 the water from a tank of known dimensions, and observing its 
 state at the commencement and close of a trial, being careful to 
 leave the water in the boib-r at the same height at which it was 
 at the commencement, and maintaining this height as constant 
 as possible during th(; experiment. In measuring tlie fuel con- 
 sumed, it is best to draw out the fire at the commencement of the 
 trial, rekindling it as soon as possible, and charging all the fuel 
 used from that time, hauling and quenching tlie fire immediately 
 at tlie closer of tin; trial, and weighing back all fuel that is uncon- 
 suMKid. In the, case of Hinall boilers heated by lamps, a measure- 
 ment of th«i oil used between the beginning and end of th(? trial 
 will gi^nerally l)e suliicient ; and if gas is employed as fuel, it 
 will h(! necessary to attach a meter to the pipts to determine the 
 (|iiaiitity consumed in any given time. 
 
 'I'o asc(;rtain tin? power of the engine, the most convenient me- 
 tliiid is, generally, to atta<h a friction-brake, shown in the ac- 
 conipanying engraving, to the bund-wheel. Hollow out two 
 pieces of wood, B and (.', so that they will tit the circumference of 
 
ENGINEERING. 
 
 85 
 
 the band-wheel, A, and attach light plates of metal, D and E, to tlie 
 sides, so tliat the pieces of wood can not slip off when secured in 
 position. Provide two belts, F, G, countersinking the heads, H 
 
 TUE nUCTION-BliAKii. 
 
 and I. into the upper piece of wood, so that they can not turn, 
 and put nuts and washers, K and L, on the other ends, so that 
 the two pieces of wood can be clamped on the band -wheel as 
 tiirhtly as is necessary. Make the upper piece of wood somewhat 
 longer than the other, and pass a rod, M, through the end. On 
 this rod weio^hts, N, are to be placed, and the lower end of the 
 rod is hooked to the piston-rod of a small cylinder. O. The pis- 
 ton, P, fits loosely in this cylinder, which is filled with oil or wa- 
 ter ; and the piston has small holes in it, so that it can move up 
 and down without much resistance, if moved slowly, but offers 
 considerable resistance to sudden motion. The action of the ap- 
 paratus will doubtless be apparent to our readers. By tightening 
 the nuts on the bolts, F, G, there will be considerable friction be- 
 tween the band-wheel and the pieces of wood. The rod M must 
 then be loaded with sufficient weight, so that the engine can just 
 move at its regular rate of speed, and keep the npper piece of 
 wood in a horizontal position. The friction on the band-wheel 
 will cause it to become heated, unless some arrangements are 
 made for cooling, either by keeping a stream of water running 
 upon it, or immersing the lower part in a trough in which the 
 water is constantly changed. The small cylinder, O, and piston, 
 P, serve to counteract the effect of sudden shocks, which would 
 otherwise throw the arm of the piece B from a horizontal position. 
 Now it will be plain that, as the band-wheel revolves (constantly 
 maintaining the arm, with the weight attached, in a horizontal 
 position), the effect is the same as if it were lifting this weight by 
 means of a rope running over a windlass, and the distance 
 through which it would lift the weight in a given time is the 
 same as the weight would move if the whole apparatus were free 
 to revolve. If, for example, the wheel makes 300 revolutions in a 
 minute, the distance from the centre of the wheel to the centre of 
 the weight is 1 foot, and the weight is 10 lbs. ; this weight, if 
 free to revolve, would move in each revolution through the cir- 
 
86 ENGIXEERING. 
 
 cumference of a circle whose radius is 1 foot, and in a minute 
 W'luld move 300 times as far, or about 1885 feet. The work of 
 the ensrine in a minute, then, will be that required to lift. 10 lbs. 
 through a heifrht of 1885 feet, or 18.850 foot lbs. ; and as one 
 horse-power is the work represented by 33,000 foot lbs. per min- 
 ute, the engine would be developing a little more than half a 
 horse-power. 
 
 In makinj; experiments with the friction-brake, the apparatus 
 should be placed loosely on the band-wheel ; and before the 
 weights are attached, a spring-balance should be secured to the 
 arm, at tlie centre of the hole for the rod M, and the reading not- 
 ed when the arm is in a horizontal position. This reading must 
 be added to the weights that are afterwards attached. The hori- 
 zontal distance from the centre of the wheel to the centre of the 
 rod M, should be carefully measured. Then start the engine, 
 with the throttle-valve wide open, and screw tip the nuts K L gra- 
 dually, adding weights at X. It will then only be necessary, when 
 sufficient weights are added, to keep the wheel cool, and occasion- 
 ally adjust the nuts K L, should the brake bind or become too 
 loose from any cause. Should it be difficult or inconvenient to 
 maintain the arm in a horizontal position, note carefully the posi- 
 tion it assumes during the test ; and for the radius to be used in 
 the calculation, measure the distance a h from the centre of the 
 wheel to the centre of the rod M, in a direction perpendicular to 
 the direction of the rod. 
 
 Instead of the weights, N, and cylinder, O, a spring-balance may 
 be attached to the end of the rod M. and secured to some fixed 
 support, its readings during the trial being used in place of the 
 attached weights. In this case, also, the weight of the apparatus 
 must be first determined, and added to the readings of the spring- 
 balance. The plan represented in tiie engraving is, however, the 
 best. 
 
 Tlie above are, in detail, the methods to be pursued in pre- 
 paring a report of the i)orformancc of small engines and boilers. 
 Although they are far from fullilling all the requirements of 
 a scientific test, they will give very accurate results if carefully 
 conducted. B. 
 
 TruRiNE WiiEET.s. Effective power of. — It is important, in se- 
 lecting a good wheel, to be assured that it will furnish amjjle 
 power. After ascertaining a reliable maker, in order to determine 
 the exact size of the whet^l it is necessary that at least one third 
 should be allowed for variations in water levels, and for the lo.ss 
 consecjuent to the wear of wiicels and gates; an<i, in addition, 
 figures should be made, based on but a little mere tluui a half 
 gate of water to the wheel. The best wheels afford almost all of 
 their power at a five-eighths gate or under, and a difference be- 
 tween a half and full gate is not more than sliould l)e the margin 
 necessarv to regulate sjieed. In use it will be found that open- 
 ing gates seven-eighths or fully simply amounts to a large 
 consuin]>tion of water, generally without producing five orten jht 
 cent additional power. Some good wheels give less p)wer when 
 at full than at i)art gates. The rule should be to buy a wIuhO 
 amply sulHcient at not much above half gate, allowance being 
 madi- for overestiiuat.- of power. We think the e\]ierieiu-e of all 
 who have jdaci-d whe«-ls w ith a less liberal allowances will bear 
 
BNGIXEERING. 87 
 
 out and confirm this rule. Allowing one fourth for the friction 
 of the sliaftint; of a cotton or woolen mill, without addinfj one 
 third more for a reserve when in actual use, will scarcely fail to 
 cal^se a manufacturer to wish that he had bought a larger wheel. 
 Actual tests, accurately conducted, of ol styles of turbines show 
 the comparative range of effective force, under the best possible 
 advantages, to be as follows : At quarter gate, from 13 to .50 per 
 cent ; half gate, from 11 to 71 per cent ; three-quarter gate, from 
 31 to 82 per cent, and at full gate, from o2 to 84 per cent, the best 
 wheels giving out about all of their power at from five-eighths to 
 three-quarters openings ; while the lower classes give but little 
 power unless flooded with water, and even then fall far short of 
 the amount claimed for them. Another reason why large wheels 
 should be used is that, almost universally, high and low points of 
 the head and tail waters so reduce the force of wheels as to cause 
 partial stopjaages of machinery, unless there is surplus power 
 when the water is at the ordinarv stage. 
 
 THE STEAM-BOILER AXD ITS ATTACHMENTS. 
 
 Boiler, Cleaning the. — The flues or tubes of a boiler should 
 be cleaned about once a week, with a brush or scraper. In case 
 incrustation has formed in them, they can be cleaned by a jet of 
 steam from a rubber hose. A boiler should be blown down 
 and cleaned, under ordinary circumstances, about once a month. 
 The fire should first be hauled ; and then, if possible, it is best to 
 let the boiler stand tintil the water becomes tolerably cool, say for 
 12 hours, after which the water may be allowed to run out. Then 
 remove the man and haudhole plates, enter the boiler, and clean 
 it with scrapers and brushes in every part that can be reached. 
 It should then be washed out with cold water from a hose, and 
 this washing with a hose is the only means of cleaning those 
 parts of a boiler that can not be reached by hand. There are 
 many boilers into which a man can not enter, and of course these 
 can only be washed out. When the fire is hauled, all leaks in 
 the boiler should be repaired. Leaky parts exposed to the fire 
 must have hard patches riveted on ; in other places soft patches 
 secured by bolts can be used, each patch having a lip around it, 
 and the joint being made with a putty composed of red and white 
 lead. Leaky rivets or seams can sometimes be made tight by 
 calking. Small leaks around the ends of tubes can often be 
 stopped in the same way, but as a general thing a leaky tube 
 must either be replaced or plugged. To plug a tube, drive a 
 white-pine plug tightly into each end, and cut it off even with 
 the tube-heads ; then pass a bolt through the tube, with cup 
 washers on each end, and screw it up tightly, putting putty under 
 the washers. B. 
 
 Boilers, Cylindrical. — Toflndthe necessary tliickness in inches 
 for the shell. — Multiply the pressure of steam in pounds per 
 square inch by the diameter of the boiler in inches, and multiply 
 this product by 0.0002 for a copper boiler with single-riveted 
 shell ; by 0.0001563 for a copper boiler with double-riveted shell ; 
 
88 ENGINEERING. 
 
 by 0.0001316 for a wrouglit-iron boiler with single-riveted shell ; 
 by 0.0001111 for a wrouo^ht-irou boiler with double-riveted shell ; 
 by 0.0001 for a steel boiler witli single-riveted shell ; and by 
 0.00008333 for a steel boiler with double-riveted shell. 
 
 In illustration of the rule, suppose that it is required to find the 
 necessary tiiickuess for the shell of a copper boiler 60 inches in 
 diameter, double riveted, for a pressure of 40 ll)s. per square inch. 
 
 First take the product of 40 and 60, which is 2400, and multiply 
 this by 0.00()ir)63, which gives 0.375, or 'j of an inch, as the neces- 
 sary thickness. 
 
 To find the safe pressure in pounds per square inch. — Divide the 
 thickness of the plate in inches by the diameter of the boiler in 
 inches, and multiply the quotient by 5000 for a copper boiler with 
 single-riveted shells ; by 6400 for a copper boiler with double- 
 riveted shell ; by 7600 for a wrought-iron boiler with sini^^le-rivet- 
 ed shell ; by 9000 for a wrought-iron boiler Avith double-riveted 
 shell ; by 10,000 for a steel boiler with single-riveted shell ; and 
 by 13,000 for a steel boiler with double-riveted shell. 
 
 Thus, to find tlie safe pressure for a boiler 33 inches in diame 
 ter, the shell being made of wrought-iron plates \ of an inch 
 thick, single-riveted : First divide -^ by 33, which gives i^^, and 
 multiply this by 7600, the product, 59g^ lbs. per square inch, being 
 the ])ressure required. 
 
 Thickness, in inches, of flat heads (not stayed). — Multiply the 
 scjuare root of the pressure in lbs. per square inch by tlie radius 
 of the shell in indies, and by 0.013333 for a head of copper ; by 
 0.010541 for a head of wrought-iron ; and by 0.0081649 for a head 
 of steel. 
 
 A steel boiler has a diameter of 24 inches, and the pressure of 
 the steam is 60 lbs. per square inch : The thickness of the head 
 is the product of 7.746 (the square root of 60), 12, and 0.0081649, 
 which is equal to 0.7766, or about ;i| of an incli. 
 
 Safe pressure, in pounds per scpiare incJi, for flut heads (not 
 stayed). — Divide the square of the tliickness of the plate in inch- 
 es bv the square of the radius of tlie shell in inches, and luulti- 
 plv the (luotient by 5625 for a head of cop])rr ; l)y !)000 for a 
 liead of wrouglit-iron ; and by 15.000 for a head of steel. 
 
 Suppose the heads of a boiler are of steel, I inch in thickness, 
 and that the diameter of the boiler is 24 inches : .25 (the square 
 of \), divided l)y 141 (the squan^ of the radin.s), is .00174, and the 
 l)roduct of .00174 and 15,000, 26 lbs., is tin; iiressun; required. H. 
 
 Bf)ri.KKs, Heating surface of. — Note : In lln' following rules all 
 dimensions ar<i to be taken in feet. 
 
 (a) (U/lindrical boilers. — Take the product of (1) tlie diameter of 
 tlie boiier, (2) the length of the boiler, and (.3) 1.5708. 
 
 Sii])]iose n given boiler has a diameter of ;56 inches, and a 
 h'Mirh of 20 feet, its lieating surface is the product of 3, 20, and 
 1.5708, or about 94J scpiare feet. 
 
 (h) Cylindrical flue boilers. — Take the product of the diameter 
 of the boih-r, the'length, and 1.5708, and add it to the product of 
 (I ) interior diameter of line, (2) length of line, {;]) number of ihu'S, 
 an<l (1)3.1416. 
 
 Snp])ose that a line boiler is I feet in dianietei-, 22 feet long, and 
 has two flues, each with an interior diameter of 15 inches. Then 
 the heating surface is <'qual to the jiroduct of 4. 22, and 1.5708, or 
 
 I 
 
KNGIJVEEBING. 
 
 89 
 
 Internal 
 
 surface in 
 
 square inches, 
 
 per foot of 
 
 length. 
 
 i> CO CO OJ l- iO Ci iO Ci CO t^ iO CO QO IC CQ i> t-~ 
 
 — 'OGOGOl^OlC-^COC'JCviOCsr-CO'-^SllOi-i 
 
 '*icioo£-c»csoT-ic.?cc-Tt<iot-^»oooo^;o 
 
 T-JTHr-lTH-r-lT-lr-CQW<?JCOCO 
 
 Internal 
 
 surface in 
 
 square feet, 
 
 per foot of 
 
 length. 
 
 ooj-^crico-^oico iocs csto-^c"? i- 
 
 05O00C0CSt^0"*X)00C000t^t~-rHTtlOX)0J-rH 
 00'*iOJ>C0CiO(^JG01Oi-lt-O0tS00'*'S^— ' 
 C>? 00 '^ -^ JO iC O t^ t^ X CS C5 ^ 0> ^ l^ O O^ i-O 
 
 000000000000-rH^T-HT-<?.-iCiCJ 
 
 outside 
 
 siirfiice in 
 
 square inches, 
 
 per foot of 
 
 length. 
 
 T-l lO 1-1 ■* 00 O? t^ tH O '^ GO £>• 1.-5 tH 05 00 CO 
 
 £-ooira-Tt<'*cocoojcQi-ic;CiOOOco-rtC5i^ 
 
 ■^iOOl-COOSO-^OlCO^lOOOOC^JOOCOt- 
 ■i-lT-lTHrH-T-li-lT-li-lOJOiCOCOCO 
 
 Outside 
 
 surface in 
 
 square feet, 
 
 per foot of 
 
 length. 
 
 0}l--0iO-rH10 '^CSCOOCC^i-H QOO'+O'J 
 
 t-0^'»COCS'* 100»T-Ht-OOCSOCQ^OGO 
 o:? Ci iO C? CO lO IN GO LO 1-H 00 ^ £> O fi CO C; O i-i 
 CO 0^ ^ O O CO t- L- CO C3 C5 O T-H CO iO 00 O CO o 
 
 OOOOOOOOOOOi-iT-i^^^OJCJOi 
 
 Internal 
 
 diameter 
 
 in 
 
 feet. 
 
 Ol 00 £- *7 00 00 1- iC t^ irti GO Oi lO 
 
 CI T-H O ^ O rH ^ o -^ C» -^ C? 01 o? »o cs o 
 C5 ^ CO lO £^ C5 T^ CO O I- C5 -rt »0 C: t- lO CO CJ C5 
 Ot-HT-li-iTHTHC^OiWO^OJCOCOCOTitiOOC^t.^ 
 
 ooooooooooooooooooo 
 
 Internal 
 diameter 
 
 in 
 inches. 
 
 OOOCOt-HCOOOCOOOt— lO-i-HCOCOOl:^i>-f>^GS 
 T-H CO iO GO O SQ O I- O C? lO t- (?} £^ «? O O O iO 
 
 
 Thickness 
 
 in 
 
 inches. 
 
 (W CO J-O Lt! iO C5 O CJ -^ -^ CO l--:! IC lo co 
 C-GOClCiOSOOOiNOJCJCOCO-^OCOOOOO 
 OOOOOi-HT--,-l,-l,-ITH,-,,-lrH,-H,-l^rHCJ 
 
 OOOOOOOOOOOOOCJOOOOO 
 
 Outside 
 
 diameter 
 
 in 
 
 feet. 
 
 c^ 00 c- lo CO ffj 00 i> »o CO t~ CO I- CO 
 
 '^iOlfflCOf^OOO Ot-iWCOIOO coo CO 
 OOJ-^OOOO'MlOt-CS-'-HCOl^— 1 OOOIOCO 
 ,-1 ^ -rt ^ T-H C"* O"? 0> Oi Ol CO CO CO ^ l.t' <o O t^ GO 
 
 ooooooooooooooooooo 
 
 Outside 
 diameter 
 
 in 
 inches. 
 
 lO to lO ,_ »0 lO LO 
 OJJCt- CQlOt- CQiOt^ lO 
 
 ^' T-H ,-; (N oj <?:(■ ei CO CO CO CO -# ^ lo o i^ 00 ej o 
 
 T-H 
 
90 
 
 ENGi:SEEEING. 
 
 nearly 138i, increased by tlie product of 1.25, 22, 2, and 3.1416, 
 or about 172f, making tlie total lieating surface 311 square feet. 
 
 (c) Cylindrical tubular boilers. — Find the product of the diame- 
 ter of the boiler, the length, and 1.5708, and add this to the pro- 
 duct of the length of the boiler, the number of tubes, and the 
 heating surface of a tube per foot of length. 
 
 The preceding table gives the heating surface per foot of 
 length for the standard sizes of tubes. 
 
 LOCOMOTIVE liOlI.ER. 
 
 JSxample. — A cylindrical tulmliir boiler has a diameter of 42 
 inches, is 10 feet long, and contains 40 tubes, each 4 inches out 
 side diameter. 
 
 The i)roduct of 3A, 10, and 1.5708 is nearly 88. 
 
 The i)roduct of 10, 40, and 0.977 (the internal surface of the 
 tube, p(M- running foot) is about 015, so that the -whole heating 
 surfaces is 703 s(|uare feet. 
 
 ((I) Lorimiotin' hi'ilcrx. — I. Add together the following cjuanti- 
 ties : (1) Tlie product of the length of tin- line l)()unding the 
 croHH-section of t lie furnace, and the length of the furnace. (2) 
 Twice the area of the cross-section of the furnace. (3) The pro- 
 duct of the hiiigth of the tubes, the niunber of tubes, and the 
 heating surface of ii tube per foot of lengtli. 
 
 II. Sul)tiiict from tliis sum tin' sum of the following (piauti- 
 ties : (I) Tlie area of the lurnace-door. (5) Tlie product of the 
 luiMiber of tu])e8, the Hcjuare of the iMternal dianuitcT of a tube, 
 and 0.7H54. 
 
ENGINEEEING. 
 
 91 
 
 As an e'xample of the use of this rule, suppose it is required to 
 determine the heating surface of a boiler having tlie dimensions 
 noted in the entrravinfrs. Fig. 1 being a cross-section of the 
 
 L( ICOMOTIVE BOILEK. 
 
 boiler at the furnace, showing also the furnace door iu dotted 
 outline, and Fig. 3 a longitudinal section. (1) The length of the 
 line bounding the cross-section of the furnace is the sum of twice 
 3.5, 1.5708, and 3.5, or 11.07, and the product of 11.07 and 4 is 
 44.28. (2) The area of the cross-section of the furnace is the sum 
 of 3.5 squared, 2i times +, and 0.7854 divided bv 2, or about 
 13.89. Twice 13.89 is 27.78. (3) The product of 8, 20" and 0.977 is 
 157.32. The sum of 44.28, 27.78, and 157.32 is 229.38. (4) The 
 area of the furnace-door is the sum of 1.5 times 1.25, and 0.3927 
 times 1.5 squared, or about 2.76. (5) The product of 20, 0.311 
 squared, and 0.7854, is about 1.52. 
 
 The smn of 2.70 and 1.53 is 4.28. The difference between 229.38 
 and 4.28 is about 325 square feet, tlie heating surface required. 
 
 (e) Vertkal boilers. — I. Take the sum of the following quanti- 
 ties : (1) The product of the diameter of furnace, height of same, 
 and 3.1416. (2) The product of the diameter of the furnace 
 squared and 0.7854. (3) The product of the number of tubes, 
 length of same, and heating surface per foot of length. 
 
 II. Subtract from this sum the product of the number of tubes, 
 the internal diameter of a tube squared, and 0.7854. 
 
 Example. — Required, the heating surface of a vertical boiler 
 with the following dimensions : Diameter of furnace, 24 inches ; 
 height of furnace, 18 inches ; 40 tubes, each 3 inches outside di- 
 
92 
 
 ES^GLfiEEBlXG. 
 
 ameter, 6 feet long. (1) The product of 2, 1.5, and 3.1416 is 
 9.43. (2) The product of 4 and 0.7804 is 3.14. (3) The product of 
 40, 6, and 0.4739 is 113.74. The sum of 9.43, 3.14, and 113.74 is 
 126.3. The product of 40,0.02374 (the square of 0.1508), and 
 0.7854 is about 0.73. The heating surface is the difEerence be- 
 tween 126.3 and 0.72, which is about 125.6 square feet. B. 
 
 BoiLEKS, Horizontal, Setting. — The best way is to have the 
 fire-box at least as wide as the boiler, and have as much heating 
 surface as possible ; but below the water-line all passages should 
 be made large, so as to allow a free passage to the heated gases, 
 and where they leave the boiler, a damper should be provided. 
 The bridge-wall should be high enough to prevent coal from 
 being thrown over, and the grates low enough to allow ample 
 room for combustion. Nothing can be gained by putting the fire 
 near the boiler or contracting any of the passages ; it is better to 
 let the heat diffuse itself fully throughout the entire heating 
 surface. 
 
 Boilers, Priming in. — If your boiler primes, either " swap" it 
 off for another or superheat your steam moderately ; but beware 
 of anti-priming doctors and their remedies. 
 
 Boilers, Rules for firing under. — (1) Begin to charge the fur- 
 nace at tlie bridge end, and keep firing to within a few inches of 
 the dead-jjlate. (2) Xever allow the fire to be so low before a 
 fresh charge is thrown in, so that there shall be at least 4 or 5 
 inches of clear, incandescent fuel on tlu- l)ars, e(iually spread over 
 the whole. (3) Keep the bars constantly and equally covered, 
 particularly at the sides and bridge end, when^ the fuel burns 
 away most rajmlly. (4) If the fuel burns une(]ually or in holes, 
 it must be leveled and the vacant spaces filled. (5) The large 
 coals must be broken in ])ieces not larger than a man's fist. (6) 
 Wliere the ash-])it is shallow, it must fr(M|U('ntly be cleaned out ; 
 a bodv of hot cinders will overheat and burn the bars. 
 
 ■^^^' 
 
 ll 
 illlllliiPiil 
 
 ffl: 
 
 C'lilMNKYS, To Htraighten tall. — Ilnve a number r)f oak wedges 
 made of HuHicient lenglli to pass through tlu-, entire thickness of 
 
ENGINEERING. 9^ 
 
 the chimney and project sufficiently on the outside. Place them 
 in sets of three each, one over the other, as shown in the en- 
 graving, having the surfaces in contact straight and smooth, 
 and black-leaded to diminish friction. Commence on the oppo- 
 site side to that in which the chimney leans ; cut through to the 
 inside, insert one set of wedges, and wedge above and under them 
 until they take a bearing. Repeat the process around the chim- 
 ney, except on the lowest side, leaving spaces of a foot or more 
 between each set of wedges. Then, by driving the centre wedge 
 in each set inwards, as much of the chimney as rests on them is 
 gradually lowered just at the places and to the amount required 
 to bring it to an exact perpendicular. When that is done, brick 
 up the intervening spaces, loosen and withdraw the wedges, and 
 brick up in their places. This requires careful and skilful work. 
 
 Chimxeys, Proportioning. — The general rule is to make the 
 cross-section of the chimney, which maybe either round or square, 
 from ^ to Yjf of the grate-surface, and the height from 50 to 70 
 feet. 
 
 To determine the amount of coal which will be burned per square 
 foot of grate per hour, with good proportions, by Professor Thurs- 
 ton's rule. — Subtract one from twice the square root of the height. 
 Example : What will be the amount of coal burned per square 
 foot of grate surface per hour, the chimney being 49 feet high, 
 and suitably proportioned ? The square root of 49 is 7 ; twice 7 
 is 14 ; 14 less 1 is 13, which is the amount of coal required in 
 pounds. 
 
 To determine tJie height required to give a certain rate of com- 
 bustion. — Add 1 to the weight to be burned per square foot per 
 hour ; divide by 2 and square the quotient. Example, same as 
 above, worked backwards, thus : What height of chimney is re- 
 quired to burn 13 pounds of coal per square foot of grate sur- 
 face per hour ? 18 and 1 are 14 ; 14 divided by 2 is 7 ; the 
 square of 7 is 49, which is the height of the chimney in feet. 
 
 Co.\L, Effect of damp air on. — It has been found by recent 
 experiments on this subject, that the loss in weight, dite to a 
 slow oxidation and to the disengagement of gases which form the 
 richest part of bituminous coal, may equal one third of the ori- 
 ginal weight. The heating power in such coal was lowered to 47 
 per cent of its former capacity. The same coal exposed to the air, 
 but in a closed receptacle, did not lose more than 25 per cent of 
 gas and 10 per cent of heating power. Bituminous coals alter 
 most rapidly. This shows the disadvantage of damp cellars, and 
 of leaving coal uncovered for long periods and subject to bad 
 weather. 
 
 CojrBUSTioN AND FuKL. — The principal constituents of coal are 
 carbon, hydrogen, water, a little sulphur, ashes and clinker, the 
 latter two substances consisting generally of silica, alumina, iron, 
 lime, magnesia, and oxide of manganese. The principal combus- 
 tible constituent of anthracite is fixed, uncombined carbon. The 
 free-burning or semi-bituminous coals contain a considerable 
 amount of hydrocarbon or volatile combustible matter, and bitu- 
 minous caking coals have a larger percentage of volatile combus- 
 tible. 
 
 If a mass of coal is brought to a sufficiently high temperature 
 
04 ENGINEERING. 
 
 (probably something above 1000' Fahr.), the combustible mate- 
 rials enter into chemical combination, and as much heat is given 
 out as would be required to decompose the resulting products into 
 their elements. When coal is burned the water is first expelled ; 
 then the sulphur, if any is contained, is consumed, forming sul- 
 phurous oxide ; after this the hydrogen in the volatile combusti- 
 ble matter unites with oxygen, forming water ; and the carbon 
 set free unites with oxygen, forming carbonic dioxide, if the tem- 
 perature is sutliciently high and enough oxygen is present, or, 
 under less favorable circumstances, either forming carbonic oxide 
 or passing off unconsumed, as soot. The combustion of the fixed 
 carbon next begins, the product of the combustion being carbonic 
 dioxide or carbonic oxide, so that liually nothing is left except 
 the ashes and clinker. 
 
 It may be well to trace the effect of these various combina- 
 tions : The water contained in the coal is expelled in the form of 
 steam, so that it carries off some heat, and is a positive disadvan- 
 tage. The complete combustion of a pound of sulphur produces 
 about 4000 units of heat, but the amount of sulphur in coal is 
 usually so slight that its heating qualities scarcely disserve to be 
 regarded. The action of tlie sulpliur on the material of the boiler 
 is, however, a very serious matter. It has not yet been determin- 
 ed by experiment what per cent of sulphur is sufficient to render 
 a coal unfit for use in a furnace, but it is well known tliat "many 
 of the Western coals produce very bad effects when employed in 
 locomotive boilers. A pound of hydrogen combining with oxy- 
 gen, forming 9 pounds of water, has a heating power of 02,033 
 units. It seems doubtful, however, whether this amount of heat 
 is available from tiu; combustion of hydrogen in a boiler. The 
 experiments by which tliis value was determined wer(> made u])on 
 liydrogen in the gaseous stat(i, and the steam resulting from the 
 combustion was condensed. Now tiie hydrogen in coal is ordi- 
 narily combined with carbon, and frequently with nitrogen, so 
 that it must b(; separated from the coiul)ination l)efore it can be 
 united with oxygen, and heat is required for this separation. 
 •Vgain, in a boiler thr ])rodu<;ts of combustion usually pass into 
 llu; chimney at such a iiigh ti^mptu'ature tluit the water, wiiich is 
 tlie result of the combustion of the hydrogen, jjasses off in the 
 form of steam, and thus carries off a considerable (luantity of 
 wliat is coinmr)iily known as latent heat. Tiiis subject is one 
 vvhicli liiis been but little considinvd by experimenters, and is 
 worthy of more extcMuhjd inv(^stig;itioii. The volatiit? comljusti- 
 bh; matter of i-oal generally contains oxygen in comliination, and 
 tiiis must b(! ciiangi'd into the gaseous state before being unittid 
 with the hydrogen, an operation that n^quires as much lieat as 
 results from tlie new combination, llciiice it is <rertain that tlio 
 amount of liydrogen contained in coal must be (limiiiished by one 
 eiglith of the weight of the oxygen liefore attempting to form any 
 estimate of its heating ipialities. 
 
 The cariion of llie coal, as has been aln^ady stated, will unite 
 with oxygen, forming (carbonic dioxide, and may afterwards lake 
 U|) more carbon, hik! lie converted into carbonic oxide. Now the 
 re.-tull of the coiiipleti- combustion of a pound of curb m is I'ji lbs. 
 of cariioiiic dioxide, and the cimilmstion piodiices 11,000 units of 
 heat. But a pound of carbon iiiiperfcictly Imrned produces 2J- 
 
ENGINEERING. 
 
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96 KNGINEEEING. 
 
 pounds of carbonic oxide, and only 4400 units of heat. In a fur- 
 nace where the combustion is imperfect, tlie action is iisually as 
 follows : A pound of carbon is at first completely burned, fori-iung 
 3| pounds of carbonic dioxide, and then takes up another pountl 
 of carbon, producing 4^ pounds of carbonic oxide and 8800 units 
 of heat. This carbonic oxide, however, if supplied with a suffi- 
 cient amount of air, will burn and again form carbonic dioxide, 
 so that the full effect of the combustion of the carbon will be 
 realized. A practical application of this principle is seen in the 
 combustion-chambers in boilers, which are designed to complete 
 the combustion of the gases after they leave the furnace. 
 
 Having disposed of the materials of the coal which escape into 
 the chimney of a boiler, the ashes and cliulier that remain should 
 be considered. The effect of these substances is injurious in se- 
 veral ways : they choke up the furnace, preventing free access of 
 the air to the combustible materials, and instead of entering into 
 combinations and producing heat, they require to be heated to the 
 temperature of the furnace, and are then removed, without hav- 
 ing produced an equivalent for the heat expended ujion them. 
 
 In ordinary boiler-furnaces, the amount of air required for the 
 combustion of 1 pound of coal is about 24 pounds, or between 
 280 and 300 cubic feet. 
 
 For a table of the qualities of American coal from various loca- 
 lities, compiled from Prof. Johnson's Report, see page 95. B. 
 
 Feed-Wateu Heaters, Gain from the use of. — A unit of heat 
 is the amount of heat required to raise the temperature of a pound 
 of water one degree, the water being at th(^ temi)erature of maxi- 
 mum density, about 39.1° Fahrenheit. The table below shows 
 the number of units of heat required to convert one pound of wa- 
 ter, at the temperature of 32", into steam of various pressures. 
 
 Pressure of steam 
 
 
 Pressure of steam 
 
 
 ill 11)9. per sq. in., 
 
 Uoitsof hetit. 
 
 in 11)8. per 8<i. in., 
 
 Units of Iieat, 
 
 by gaii-;e. 
 
 
 by gauge. 
 
 
 1 
 
 1148 
 
 10 
 
 1155 
 
 20 
 
 1161 
 
 30 
 
 1105 
 
 40 
 
 1169 
 
 50 
 
 1173 
 
 GO 
 
 1170 
 
 70 
 
 1178 
 
 80 
 
 1181 
 
 90 
 
 1183 
 
 100 
 
 1185 
 
 1189 
 
 . . . . 1192 
 
 110 
 
 1187 
 
 120 
 
 130 
 
 1190 
 
 140 
 
 150 
 
 170 
 
 1193 
 
 100 
 
 1195 
 
 1190 
 
 180 
 
 1198 
 
 190 
 
 1199 
 
 200 
 
 1200 
 
 
 
 In a non-condensing engine, if the exhaust steam escapes di- 
 rectly into tiu! atmospllen^ it carrii-s off most of the lieat tiuit was 
 |)reviously iiiipiirte<l to it by the coai in the furnace. This may 
 l)e illustrated i)y an exain|)ie. 
 
 Suppose the steam is admitted into the cylinder of an engin(! at 
 a pressurt! of 90 poiiiids ])er s(|uare inch, and exhausted at a pres- 
 sure of 1 pound above the atmosphere, and that the temperature 
 of tlie fi-i-d water is 70 . if the f.-ed wiiter had l)een at 32', it will 
 he seen that eacli jjound of water would have re(|uire(l 1183 units 
 yf heat to convert it into steam of !)(» jiounds pressure ; but since 
 
ENGINEERING. 97 
 
 tlie temperature of the feed was 38" above 32°, 38 units less, or 
 1145, will be necessary. The exhaust steam carries away 1148 
 less 38, or 1110 units of the heat that has been imparted to the 
 steam by the coal, so that about 96.94 per cent ot the heat is 
 thrown away. Now, it costs money to heat this water, and the 
 steam-user who pays $6.50 a ton for coal, which converts 15,000 
 pounds of water into steam, might make up an account some- 
 what after this manner: "After evaporating 15,000 pounds of 
 water at a cost of $0.00043+ per pound, I allowed 14,541 pounds 
 to escape into the air without rendering me any equivalent, and 
 only utilized 459 pounds in my engine ; so that really I pay at 
 the rate of $0,014+ for every pound of water used." 
 
 There are many steam-users to-day who could readily make up 
 an account somewhat like the preceding. 
 
 Now suppose that the steam-user, being convinced of the folly 
 of paying for coal to raise steam wliich is blown away without 
 doing any good, attaches a heater to his exhaust-pipe, and so 
 raises the temperature of the feed-water to 300', instead of TO'', 
 as before. If this is done, and the heater is a good one, which 
 does not increase the back pressure, each pound of water requires 
 130 units less for its evaporation, and each pound of exhaust- 
 steam carries away 130 units less than before ; and the steam-user 
 can make up his account anew, as below : 
 
 "One ton of coal now evaporates about 16,900 pounds of water, 
 at a cost of $0.00038 per pound, and 600 pounds of this water are 
 utilized in the engine ; so that 1 now pay $0.0108 for each pound 
 of water that produces useful effect." 
 
 If he had an engine of 100 horse-power, using 30,000 pounds of 
 steam a day, and working 300 days in a year, he would find that 
 the difference in his coal l)ill, before and after the change, would 
 be the difference between $3870 and $3420, or $450. B. 
 
 Fire-Clay for boiler-furnaces. — Take common earth, well 
 mixed with water, to which is added a small quantity of rock- 
 salt ; let the water stand until the salt dissolves, which will take 
 about 2 or 3 hours. It is then ready for use. Apply it as fire- 
 clay is used, and your furnace will stand much longer. 
 
 Flue-Sheets, To calk leaks in.— Use a reflector (a tin plate 
 will do) adjusted in front of the furnace-door, so as to throw 
 light on to the flue-sheets, while calking leaks. 
 
 Flues, Whovgkt-Iros.— Thickness in inches of a wrought-iron 
 flue exposed to external pressure : I. Find (1) the product of the 
 diameter of the flue in inches, (2) the length of the flue in feet, (3) 
 the pressure of steam in lbs. per square inch, and (4) .000,009,091. 
 
 II. Extract the square-root of this product. 
 
 Suppose, for example, that a flue is 12 inches in diameter and 6 
 feet long, and that the pressure of steam is 40 lbs. per square inch : 
 The product of 12, 6, 40, and 0.000,009,091 is about 0.02618, and 
 the square-root of this number is 0.1618+, or about -j4j of an inch. 
 It will be observed that the thickness of a flue increases directly 
 as the length. Thus, other things being equal, a flue that is 12 
 feet long must be twice as thick as one that has a length of 6 
 feet. In making long flues, it is common to strengthen them at 
 intervals by bands, thus converting them into a series of short 
 flues, so far as the strength is concerned. 
 
98 ENGINEERING. 
 
 Safe pressure in lbs.j)cr square inch for a wroxght-ircn flue 
 exposed to external j)ressure : Multiply the squsire of the thickuess 
 in inches bv 110,000, and divide this product by the product of 
 (1) the diameter of the flue in inches, and (2) the length of the 
 flue in feet. 
 
 Exeimple. — What is the safe pressure for a flue 15 inches in 
 diameter, 8 feet long, and f of an inch thick '? 
 
 The product of 0.140,625 (the square of the thickness) and 110,- 
 000 is 15,468.75. Dividing this by 15 times 8, or 120, the quotient 
 i.s about 128.9 lbs., the pressure required. B. 
 
 Gauges, mercurial steam. Keeping clean. — This can be done by 
 putting a little glycerine or sulphuric acid on the surface of the 
 mercury. This serves as a lubricator of both glass and metals, 
 and prevents their adhi'sion. 
 
 (tauges. Water and steam. — When a boiler is in use, the 
 gauge-cocks should frequently be tried to see that they are not 
 choked up, and the glass gauge should often be blown out. After 
 ascertaining the proper place iov tlie weight on the lever of the 
 safety-valve, a stick should be secured to the lever with wire, so 
 that the l)all can not be moved out any further. A cord should be 
 secured to the safety-valve lever, within easy reach of the engi- 
 neer, so that the valve can be opened by hand if it sticks, and 
 the safety-valve should be tried at least once every day, to ascer- 
 tain whether or not it is in working order. 
 
 A steam-gauge should be tested at least once a year, and the 
 engineer should frequently try its accuracy by allowing the 
 steam to raise the safety-valve, and noting the pressure shown 
 by the gauge. The hand of a steam-gauge sometimes sticks, and 
 the engineer should taj) the face of thegauge lightly several times 
 a day, to assure himself that it is in working order. He may 
 also shut off the steam from the gauge-pijje, and open the drip- 
 cock, noting whether the hand goes back pronijttly to 0, and re- 
 turns to the former reading when steam is again turned on. 
 
 In testing a boiler, warm Avater should be used, and a better 
 test, when this is possible, is to enter the boiler and make a 
 tliorough internal examination. 
 
 In leaving a l>()iler for tin- night, the fire may either be hauled 
 or banked. If it is to be l)anked, it should first be cleaned and 
 then puslied back and covered with coal, the b(»iler being left 
 with the furnace-door open and the damper closed. B. 
 
 Joints, Rivktkd, Proportions of. — {a) Diameter of riret in 
 inehes : Multiply the thickness of plate in inches l)y 3 for plates 
 up to f of an inch thick, by 1.5 for plates from f to J of an inch 
 thick, by 1.25 for jilatr-s from § to J of an inch thick, and l)y 
 1.125 for plates from J to 1 inch thick. 
 
 {h) Lemjth <f rirrt iinder the head, in inches : Multiply the 
 tliicknesrt of the ]>hite in ini'hcs by 4.5. 
 
 {c) Distance between ricets, fnnn centre to centre, in inches : (1) 
 Sinf/lc-rire.led joi/its : Multii)ly the thickness of jilate in inches by 
 (! for ])lates up to J of an inch thick, l)y 5 for plates from ^ to 8 
 of an incli thick, by 4 for ])Iates from | to | of an imh lliick, and 
 by :{ for platfs from i, to 1 inch thick. 
 
 (2) /'Jach line of rirets, (fmtldi -rirefed Juiiits : -Multiply the tliicl;- 
 uoss of the plate in inches by 7 for plates up to i of an inch thick, 
 
ENGINEERING. 
 
 99 
 
 by 6 for plates from J to -j^- of an inch tliick, by 5 for plates from 
 uf to Tb' of an inch thick, and by 4 for plates from t^^ to 1 inch 
 thick. 
 
 (d) Lap to be given to joint, in, inches: (1) Single-riveted joints : 
 Multiply the thickness of plates in inches by 6 for plates up to f 
 of an inch thick, by 4.5 for plates from |- to f of an inch thick, 
 and by 4 for plates from f to 1 inch tliick. 
 
 (2) Double-riveted joints : Multiply the thickness of plate in in- 
 ches by 10 for joints up to f of an inch thick, by 7.5 for joints 
 from I to f of an inch thick, and by 6.7 for joints from f to 1 
 inch thick. 
 
 A table is appended, giving the thickness of plate in decimals 
 of an inch, varying by sixteenths : 
 
 Halves. 
 
 Fourths. 
 
 Eighths. 
 
 Sixteenths. 
 
 Decimals. 
 
 
 1 
 
 1 
 
 3 
 
 1 
 
 0.0625 
 
 
 3 
 
 0.125 
 
 
 3 
 
 0.1875 
 
 
 4 ...:..:.. 
 
 0.25 
 
 
 2 
 
 3 
 
 5 
 
 0.3125 
 
 
 6 
 
 0.375 
 
 
 4 
 
 7 
 
 0.4375 
 
 1 
 
 8 
 
 0.5 
 
 
 3 
 
 4 
 
 5 
 
 9 
 
 0.5625 
 
 
 10 
 
 0.625 
 
 
 6 
 
 7 
 
 11 
 
 0.6875 
 
 
 12 :.. . 
 
 0.75 
 
 
 13 
 
 0.8125 
 
 
 14 
 
 15 
 
 0.875 
 
 
 8 
 
 0.9375 
 
 3 
 
 16 
 
 1 
 
 
 
 
 
 The following example will serve to illustrate the rules : 
 What should be the proportions of a single-riveted joint for a 
 boiler made of plates -| of an inch thick V 
 
 Diameter of rivets is twice 0.125, or J of an inch. Length of 
 rivets under head is 4.5 times 0.125, or -,\- of an inch. Distance 
 between centres of rivets is 6 times 0.125, or f of an incb. Lap 
 of joint is 6 times 0.125, or f of an inch. B. 
 
 Lead, Effect of steam on. — Lead iu contact with steam under 
 pressure of over 10 lbs. per square inch very soon loses its 
 strength, and it is therefore good neither for packing joints nor 
 for conveying steam. 
 
 Pipes, Steam, Burst. — Steam-pipes which have cracks in them 
 from having burst, may be repaired by heating and then soldering 
 them. 
 
 Pipes, Ste.\m, Condensation in subterranean. — To prevent this, 
 inclose the pipe in another larger pipe, and fill the space between 
 the two with plaster-of-Paris or charcoal. The outside pipe 
 should be water- tight. 
 
 Pipes, Steam, Isolating material for. — Take 182 lbs. limestone, 
 385 lbs. coal, 275 lbs. clay, and 330 lbs. sifted coal-ashes. This 
 is finely pulverized, and mixed with 660 lbs. water, 11 lbs. sul- 
 
100 ENGINEERING. 
 
 phuric acid at 50" B., and about 160 lbs. calves' hair or liog- 
 bristles. Tlie compound is applied to the pipes in coats of 0.4 
 inch thickness, repeated until a thickness of an inch and a half 
 is obtained, when a light covering of oil is given. 
 
 Pipes, Steam, To prevent cracking, from freezing. — Steam-pipes 
 apt to fill with condensed water and burst from freezing should 
 have small holes with plugs to them, the plugs to be taken out 
 at night. 
 
 Sawdust as Fuel, To burn. — A saw-mill owner solves the 
 problem of using saw-dust as fuel as follows. His boiler was a 
 return tubular, 14 feet inches long and 54 inches in diameter, 
 with 04 three-inch tubes, and brick firebox 48 x 56 x 27 inches 
 high ; bridge- wall was 7 inches at centre, rounded to the sides 
 of boiler. He states : "I lowered the bridge-wall 13 inches 
 (keeping the same circle as before), lowered the paving in rear 
 of firebox to a level with the grate-bars, and obtained a barrel of 
 furnace-slag from 3 to 7 or 8 inches in size and 1 or li inches 
 tliick, which I placed on the grate-bars, about half covering 
 them. I fired with wood ; and when the slag got heated, I 
 threw in the sawdust, which burned very well but smoked fear- 
 fully (clouds would arise from the smoke-stack). I then intro- 
 duced a 21nch pipe, with about fifty ^-inch holes, directly behind 
 the bridge-wall, leaving l)oth ends of pipe open ; after which, I 
 never had a particle of trouble either in keeping up steam or in 
 burning up the smoke. Not even in firing up did I ever see any 
 smoke come out of the stack, which was 30 feet high and 32 
 inches square, enlarged near top and to the top to 30 inches in- 
 side measurement. I forgot to state that I covered the top of 
 boiler with sheet-iron, tlien laid brick on it, covering the inter- 
 stices with sand. The sheet-iron was to prevent the sand from 
 wedging off the wall when tlie boiler expanded." A system of 
 alternate firing, and with grates so arranged as to peimit some 
 charred fuel to fall througli and burn in the ashpit, gives the 
 best results. 
 
 Scale in Stkam-Boflers, Prevention of. — (1) Use as pure 
 water as your locality affords. (3) Clean and scrape your boiler 
 as often as you possibly can. (3) Blow off without excess. (4) 
 In case of salt or brackish waters, never use steam of over OO 
 lbs. i)ri'.ssiir(^ to tlie sij. in. (5) In case of suli)hateof lime waters, 
 ncn'cr use steam of over 70 lbs. pressure. (6) In case of water 
 holding carbonate of lime in solution, pass it through a feed- 
 water heati'P made liot by exhaust steam or waste heat. (7) In 
 case; of muddy waters use large feed-water cisterns or reservoirs, 
 Oh tin- l)ottom of which the suspended earthy matters will soon 
 form a soft deposit, when tlu; surface water can be drawn ofi' for 
 use. Winm using hard water, save the drippings of the exhaust- 
 j)ipe, and tin; condensation of tlio safety-valve blow-oiT, and 
 from the cylinder, and use the water thus obtained to fill tlio 
 boiler after blowing off. The result will be surprising in its ef. 
 feet in loosening scale. 
 
 Slack, To burn as fuel. — A correspondent, who has practical- 
 ly inv(;Htigated this subject extensivc-ly, says : Slack nMpiires 
 the grate bars to be very open. I have used bars with open- 
 
ENGINEERING. 
 
 101 
 
 Ings of li inches. The only secret in using slack with any 
 kind of a furnace is to have the grate-bars open enougli so that 
 the fire can be l^ept open from the under side of the grates with 
 the poker. Some coal, of course, will go through at first ; but 
 coarse coal and wood can be used to start with, and what falls 
 through the grate must be raked out and put in again. The coal 
 will soon cake so that it will not waste. Make the furnace wider 
 than usual, in building it, with doors in the side of the front, 
 similar to furnaces for burning sawdust. For some varieties of 
 coal, it will be found beneficial to wet the coal before throwing 
 it into the furnace ; this helps to run the coal together. Then 
 put in the coal at the side doors, and let it alone till it cakes ; 
 then with the poker roll it into the centre of the fire. It will be 
 in large lumps and will not waste, and there will always be a 
 good fire in the centre. Never smother it with fresh coal. A 
 system of introducing comminuted fuel with the air required for 
 its combustion, by means of a fan-blower, has been introduced 
 by a Boston firm. 
 
 Specific Heat. — Table showing the number of units of heat re- 
 quired to raise the temperature of one pound of a substance one de- 
 gree Fahrenheit. 
 
 Copper. 0.09515 
 
 Corrosive sublimate. . . . 0.06889 
 
 Corundum 0.19762 
 
 Diamond 0.14687 
 
 Ether (liquid) 0.50342 
 
 " (vapor) 0.48100 
 
 Fusel Oil 0.56400 
 
 Galena 0.05086 
 
 Glass 0.19768 
 
 Glucinum 0.23080 
 
 Gold 0.03244 
 
 Graphite 0.20083 
 
 Hydrochloric acid 0.18450 
 
 Hydrogen 3.40900 
 
 Ice 0.47400 
 
 Iceland spar 0.20858 
 
 Indium 0.05700 
 
 Iodide of mercury 0.04197 
 
 " potassium 0.08191 
 
 " silver 0.06159 
 
 Iodine (solid) 0.05412 
 
 (liquid) 0.10822 
 
 Iridium 0.03259 
 
 Iron 0.11380 
 
 Iron pyrites 0.13001 
 
 Lead (solid) 0.03065 
 
 " (liquid) 0.04020 
 
 Lithium 0.94080 
 
 Magnesium 0.24990 
 
 Manganese 0.12170 
 
 Marble 0.20989 
 
 Mercury (liquid) 0.03332 
 
 Air 
 
 0.23740 
 
 Alcohol (liquid) 
 
 0.61500 
 
 " (vapor) 
 
 0.45340 
 
 Aluminum 
 
 0.21430 
 
 Ammonia (vapor) 
 
 0.50830 
 
 Anthracite coal 
 
 0.20100 
 
 Antimony 
 
 0.05077 
 
 Aragonite 
 
 0.20850 
 
 Arsenic 
 
 0.08140 
 
 Benzine 
 
 0.45000 
 
 Bismuth (solid) 
 
 0.03084 
 
 (liquid) 
 
 0.03630 
 
 Bituminous coal 
 
 0.20085 
 
 Boron 
 
 0.25000 
 
 Brass 
 
 0.09391 
 
 Bromine (liquid) 
 
 0.10700 
 
 " (gas) 
 
 0.05550 
 
 Cadmium 
 
 0.05669 
 
 Carbonic acid 
 
 0.21630 
 
 " oxide 
 
 0.24500 
 
 Chalk 
 
 0.21485 
 
 Charcoal 
 
 0.24150 
 
 Chloride of barium 
 
 0.89570 
 
 " " calcium. .. . 
 
 0.16420 
 
 "lead 
 
 0.06641 
 
 " " magnesium 
 
 0.19460 
 
 " " manganese. 
 
 0.14250 
 
 Chloride of strontium. . 
 
 0.11990 
 
 "zinc 
 
 013618 
 
 Chlorine (gas) 
 
 0.12100 
 
 Chromium 
 
 12000 
 
 Cobalt 
 
 0.10730 
 
102 
 
 ENGINEERING. 
 
 Mercury (solid) 0.03192 
 
 Molybdenum 0.07218 
 
 Nickel 0.11080 
 
 Niobium 0.06820 
 
 Nitrate of sodium 0.27821 
 
 " silver 0.14:r)'j 
 
 Nitre 0.2:!s:,j 
 
 Nitric oxide 0.28150 
 
 Nitrogen 0.24380 
 
 Nitrous oxide 022380 
 
 Oil of turpentine (liq'd) 0.4G727 
 " " " (vapor). O.oOGlO 
 
 Olefiant gas 0.40400 
 
 Olive oil 0.31000 
 
 Osmium 0.03113 
 
 Oxygen 0.21750 
 
 Palladium 0.05928 
 
 Petroleum 0.46840 
 
 Phosphorus 0.18870 
 
 Platinum 0.03243 
 
 Potas.sium 0.10956 
 
 Rhodium 0.05803 
 
 Ruthenium 006110 
 
 Salt 0.17295 
 
 Sapphire 0.21737 
 
 Selenium 0. 
 
 Silica 0. 
 
 Silicon 0. 
 
 Silver 0, 
 
 Sodium 0. 
 
 Steam. ... 0. 
 
 Steel 0. 
 
 Sulphide of carbon 0. 
 
 " zinc 
 
 Sulphur (native) 0. 
 
 (purified) 
 
 (liquid) O 
 
 Sulphuric acil 
 
 Tantalum 0, 
 
 Tellurium 
 
 Thallium 
 
 Thorhium 
 
 Tin (solid) 
 
 " (liquid) 
 
 Tungsten 
 
 Uranium 
 
 Vanadium 
 
 Water 1. 
 
 Wood spirit 
 
 Zinc 
 
 07446 
 19132 
 ,17740 
 ,05701 
 29340 
 48050 
 11750 
 ,15700 
 .12813 
 ,17760 
 ,20259 
 ,23400 
 34300 
 .04840 
 .04737 
 .03355 
 .05800 
 05623 
 06370 
 .03342 
 06190 
 .08140 
 00000 
 64500 
 09555 
 B. 
 
 Staved Sukface, Safe pressure, in lbs. per square inch, for 
 a. — Divide the scjuare of the thickness of the jdate in inches, by 
 the square of the distance between stays, in inches, and multiply 
 the (juotient by 16,875 for a cojjper plate, by 27,000 for a 
 wrought-iron plate, and by 45,000 for a steel i)late 
 
 JSxanqjle. — What is the safe jiressure for a plate of wrought 
 iron, i of an inch thick, secured by stays G inches from centre to 
 centre ? 
 
 The quotient arising from dividing 0.0625 (the square of i) by 
 36, is 0.00174. Multii)lying 0.00174 by 27,000, the product is the 
 required pressun;, about 47 lbs. per scjuare iucli. B. 
 
 Stayed Suuface, Thickness of, in inches. — Multiply the 
 square root of the pressure, in lbs. i)er scjuare inch, by the dis- 
 tance between centres of stays in inches, and nuiltii)ly this ])ro- 
 ducl by 0.007698 for a (•<)i)|M'r pint.-, by 0.()()6()S5S for a wroiight- 
 injn jjlate, l)y 0. 00171 II for a stci'l ))latc. 
 
 For a cop])ir lire box, in which the stays are 10 inches apart 
 from centre to centre, and the pnissure f)f steam is 60 lbs. : The 
 thickness of plate is th(! product of 7.7 Ki (the scjuare root of 60), 
 
 of an 
 B. 
 
 wliicli is e(|iial to 0.596, or about \'i 
 
 10. and 0007698 
 inch 
 
 St.\y, Proper diameter for a, in inches.— Multiply tlie distance 
 between stays, in inclies, by tlir- winare root of the ])ressure, in 
 pounds per sipiure inch, and nniltiply this prodiu-t by 0.0206 for 
 a c |)per stay, by ().OI7«4 lor a wrought iron stay. 
 
 Era mplc.—Wi' hat is tlie proi)er diameter loi wrought-iron 
 
ENGHSTEERIIfG. 1 03 
 
 stays, 6 inches between centres, tlie pressure of steam being 75 
 i:)ounds per square inch ? 
 
 This is the in-oduct of 6, 8.66 (the square root of 75), and 
 0.01784 ; which is equal to 0.92697, or about |f of an inch. B. 
 
 Stats, Distance between, in inches. — Divide the thickness of 
 tlie plate, in inclies, by the square root of the pressure, in lbs. 
 per square iucli, and multiply the quotient by 180, if the stayed 
 surface is copper ; by 164, if the stayed surface is wrought iron ; 
 by 212, if the stayed surface is steel. 
 
 Suppose the fire-box of a boiler is to be made of steel plates, f 
 of an inch thick, and the pressure of steam is to be 100 lbs. per 
 square inch. 
 
 Divide 0.375 by 10, and multiply the quotient, 0.0375, by 212 ; 
 which gives 7.95, say 8 inches, as the proper distance between 
 stays. B. 
 
 Note. — The rules for stayed siirfaces and flat boiler-heads are 
 adapted from methods explained bv Dr. Grashof in " Die Festig- 
 keitslehre," Berlin, 1866. 
 
 VaXiVE, Safety, A simple test for determining the accuracy 
 of. — Secure the valve-stem of the safety-valv^e to the lever with 
 wire or string, and attach a loop to the lever, into which pass 
 the hook of an accurate spring-balance, arranging the loop so 
 that it is directly over the centre of the valve-stem. Then take 
 hold of the iipper part of the spring-balance, and lift the valve 
 slightly, noting the reading of the balance. Measure the lower 
 diameter of the safety-valve, and find its area ; divide the read- 
 ing of the spring-balance by the area of the valve, and the result 
 will be the pi-essure, in pounds per square inch, at which the 
 steam will raise the safety-valve. Suppose, for instance, that 
 the diameter of the safety-valve is 1 inch ; its area will be about 
 fuWo of an inch. Xow, if the tension of the spring-balance in 
 raising the valve is 130 lbs., the pressure at which the valve will 
 rise is the quotient arising from dividing 120 by -/tAnnj) or 153 lbs. 
 per square inch. 
 
 A table is appended, gi^^ng the areas of valves for the ma- 
 jority of cases that occur in practice : 
 
 Table of Areas of Valves of Different Diameters. 
 Diameter of valve in inches. Area of valve in square inclies. 
 
 i or 0.5 13-64 or 0.19635 
 
 f or 0.625 5-16 or 0.30G80 
 
 for 0.75 7-16 or 0.44179 
 
 i or 0.875 19-32 or 0.60132 
 
 1 25-32 or 0.7854 
 
 li or 1.25 1 15-64 or 1.2272 
 
 H or 1.5 1 49-64 or 1.7671 
 
 li or 1.75 2 13-32 or 2.4053 
 
 2 3 9-64 or 3.1416 
 
 2i or 2.5 4 29-32 or 4.9087 
 
 3 7 1-16 or 7.0686 
 
 3ior3.5 9 5 8 or 9.6211 
 
 4 13 9-16 or 12.5664 
 
 • , 4| or 4.5 15 29-33 or 15.9043 
 
104 ENGIXEERING. 
 
 Diameter of valve in inches. Area of valve in square inches. 
 
 5 19 41-64 or 19.635 
 
 5i or 5.5 28 49-64 or 23.7583 
 
 6 28 9-82 or 28.2744 
 
 B. 
 
 Vi LVE, Safety, Hints concerning the. — Some convenient ar 
 rangi nieut, such as a cord or lever, should be fitted to a safety- 
 valve, so that it can readily be opened by hand ; and the valve 
 should be moved at least once a day, to keep it in good workiuj; 
 order. A simple experiment to determine whetlier or not the 
 valve is in truth a safety valve can readily b(=i made by everv 
 steam-user. It will only be necessary to shut off tlie steam from 
 the engine, or wlierever else it is used, and making up a good 
 fire in the boiler, observe whether the pressure increases materi- 
 ally beyond the point for which the valve is set. This experiment 
 can be made without the slightest danger, since, if the valve 
 will not relieve the boiler automatically, it can be opened to anv 
 desired extent by hand. Any one can readily perceive the ini- 
 portance of making this test, for with a good safety-valve in 
 working order, the chances of a disastrous boiler explosion are 
 greatly diminished. B. 
 
 Valve, Safety, Proper diameter, in inches, for a. — This de- 
 pends upon (1) the steam-pressure to which the valve is ex- 
 posed ; (2) the lift of the valve ; (3) tlie (luautity of steam that 
 must be discharged in a given time, in order to prevent an in- 
 crease of pressure. These quantities having been determined, it 
 is necessary to calculate (1) the area of opening required in order 
 to discharge tlie given quantity of steam ; (2) tlie diameter of a 
 valve tliat will afford the required area of opening with the 
 given lift. 
 
 The method of making these calculations is explained below. 
 
 A. IJie area of apening, in squ<tre inches, required, in order that 
 a safety-valve may prevent the increase of steam-pressure beyond a 
 given point. 
 
 (a) For stationary and marine boilers with natural draft : Take 
 the product of (1) the area of the grate-surface in .-square feet, and 
 (2) 2.63, and divide tliis product by the steam-pressure as shown 
 by gauge, increased by 14.7. 
 
 {b) For stationary and marine Ijoilers with forced draft : Take 
 the ])rodui-t of (1) the area of the grate surface in square feet, 
 and (3) 4.08, and divide this product by the stcam-prt's.siire as 
 shown by gaiigi;, increased l)y 14.7. 
 
 (c) For loaunotive boilers : Take the i)roduct of (1) the area 
 of the grate-surface in stjuare feet, (2) 11.67, and divide this 
 l)r<Kluct by the steam-pressure as shown bv gauge, increased by 
 14.7. 
 
 'I'o illiistriite the rules, su])pi)se that the steam-])ressuro in a 
 locomotive jjoiler is 150 lbs. by gauge ; wliat is tlie proi)er area of 
 opening for the esfMipt; of steam by the safety-valvo, the grate- 
 Hurfaci^ l)eing 16 scjnare U'vX't 
 
 The product of 1(1 and 11. ((7 is 186.72, and the quotient arising 
 from dividing' thi.s In tin- sum of 150 and 14.7, or 161.7, is about 
 llVo square ini'hes, whi(;h is the recjuired area of opening. 
 
ENGINEERING. 
 
 105 
 
 Divide this 
 (2) tlie sine of 
 
 B. The diameter of valve, in inches, required, to afford the neces- 
 sary area of opening loith the given lift. 
 
 (rt) When the lift of the valve is equal to or less than the 
 depth of the seat : Diminish the required area of opening by the 
 product of (1) the square of the lift, in inches ; (2) the square 
 of the sine of the angle of bevel of the valve ; (oj the cosine of 
 the angle of bevel of the valve, and (4) 3.1416. 
 difference by the product of (1) the lilt in inches 
 the angle of bevel of the valve, and (3) 3.1416. 
 
 (6) When the lift of the valve is greater than the depth of 
 the seat : Diminish the required area of opening by the product 
 of (1) the square of the depth of seat, in inches ; (2) the square 
 of the sine of the angle of bevel of the valve ; (3) the cosine of 
 tlie angle of bevel of the valve, and (4)3.1416. Divide this 
 difference by 3.1416 times the sum of (1) the depth of seat in 
 inches, multiplied by the sine of the angle of bevel of the valve, 
 and (2) the difference between the lift and the depth of seat, in 
 inches. 
 
 A table of sines and cosines of angles from 20° to 50° will be 
 found below, and an example is appended in illustration of the 
 rules. 
 
 Angle. 
 
 Sine. 
 
 Cosine. 
 
 Angle. 
 
 Sine. 
 
 Cosine. 
 
 20° 
 
 .342 
 
 .940 
 
 36° 
 
 .588 
 
 .809 
 
 21° 
 
 .358 
 
 .934 
 
 37° 
 
 .602 
 
 .799 
 
 22° 
 
 .375 
 
 .927 
 
 38° 
 
 .616 
 
 .788 
 
 23° 
 
 .391 
 
 .921 
 
 39° 
 
 .629 
 
 .777 
 
 24° 
 
 .407 
 
 .914 
 
 40° 
 
 .643 
 
 .766 
 
 25° 
 
 .423 
 
 .906 
 
 41° 
 
 .656 
 
 .755 
 
 26° 
 
 .438 
 
 .899 
 
 42° 
 
 .669 
 
 .743 
 
 27° 
 
 .454 
 
 .891 
 
 43° 
 
 .682 
 
 .731 
 
 28° 
 
 .469 
 
 .883 
 
 44° 
 
 .695 
 
 .719 
 
 29° 
 
 .485 
 
 .875 
 
 45° 
 
 .707 
 
 .707 
 
 30° 
 
 .500 
 
 .866 
 
 46° 
 
 .719 
 
 .695 
 
 31° 
 
 .515 
 
 .857 
 
 47° 
 
 .731 
 
 .682 
 
 32° 
 
 .530 
 
 .848 
 
 48° 
 
 .743 
 
 .669 
 
 33° 
 
 .545 
 
 .839 
 
 49° 
 
 .755 
 
 .656 
 
 34° 
 
 .559 
 
 .829 
 
 50° 
 
 .766 
 
 .643 
 
 35° 
 
 .574 
 
 .819 
 
 
 
 
 Example. — A safety-valve has a bevel of 33°, a depth of seat of 
 i inch, and is required to give an area of opening of 2 inches, 
 with a lift of \ inch. What should be its diameter? 
 
 Square of depth of seat 0.0625 
 
 Square of sine of 33' 0.297 
 
 Product 0.019 
 
 Cosine of 33= 0.839 
 
 Product •- 0.016 
 
106 BNGINEEUING. 
 
 Product (broujrlit forward) 0.016 
 
 Multiply by i5.1410' 
 
 Product 0.05 
 
 Area of opening 2.00 in. 
 
 Subtract 0.05 
 
 DifEerence is 1.95 
 
 Depth of seat 0.25 
 
 Sine of 33° 0.545 
 
 Their product 0.136 
 
 Multiply by 3.141C 
 
 Product 0.427 
 
 Lift 0.50 
 
 Subtract depth of seat 0.25 
 
 The difierence is « . . .0.25 
 
 Multiply by 3.1416 
 
 And the product is 0.785 
 
 Add 0.427 
 
 1.212 
 Now 1.95 divided by 1.212 gives the diameter of valve, 1.61 
 inches, nearly. B. 
 
 V.\LVK, Safety, Proportions of parts of. — 1st. To find the pres- 
 sure per square inch (it which (Kjimn caloe mill open. Measure the 
 following distances horizontally from the fulcrum to (1) the 
 centre of the valve-stem ; (2) the centre of tlie weight ; (3) the 
 centre of gravity of the lever, or the point on whicli it will bal- 
 ance if jilaced upon a knife-edge. Measure the diameter of the 
 valve, and determine its area, eitlier from a table or by multiply, 
 ing the square of tlm diameter by 0.7H54. Find the weight of 
 
 (1) the valve; (2) the lever; (3) the ball. Multiply (1) the 
 weight of the ball by its liorizontal distance from the fulcrum ; 
 
 (2) the weiglit of the lever by its horizontal distance from the 
 fulcrum ; (3) the weight of th(i valve by its horizontal distance 
 from \\\v. ful(Tum ; (4) tlu; area of the valve by its horizontal 
 distance from the fulcrum. Add togetlu'r thelirst three proilucts 
 and divide the sum by the fourth product. 
 
 Hxdinplc. — A givtMi safety-valve has a weight of 50 lbs. 21 
 inches from th(! fulcrum, th(! lever weighs (i lbs., and its (•eiitr(^ of 
 irravity is 15 inches from the fulcrum ; the weight of i\w valv(^ 
 is 2 lbs., and its centre is 4 inches from the fulcrum. The dia- 
 met(!r of tlie valve is 2 inches. At what pressure will the valve 
 b(!gin to riseV 
 
 Scjuarc! of diameter 4 
 
 Multiply by 0.7H5I 
 
 Area of valve in stpiare inclies 3.1416 
 
 (1)50 times 24 is 1200 ; (2) 6 times 15 is 90; (3) 2 times 4 is 
 
ENGINEERIXG. 107 
 
 8 ; (4) 4 times 3.1416 is 12.5G64. The sum of (1), (2), and (3) is 
 1298, which divided by 12.5604 (the fourth product) is 103.03, 
 the pressure in lbs. per square inch at which the valve will open. 
 
 2d. I'd find where to place the weight on a safety-valce so that it 
 shall open at a given pressure of steam. Multiply (1) the weight 
 of the lever by the horizontal distance of its centre of gravity 
 from the fulcrum ; (2) the weight of the valve by its horizontal 
 distance from the fulcrum ; (3) the area of the valve by the 
 pressure of steam in lbs. per square inch, and by the horizontal 
 distance of the valve fi'om the fulcrum. Add together the first 
 two products, subtract their sum from the third product, and di- 
 vide the difference by the weight of the ball. 
 
 Example. — The ball of a safety-valve weighs 100 lbs., the 
 lever weighs 10 lbs., the valve weighs 2 lbs., and has a diameter 
 of 3 inches. The distance of the centre of gravity of the lever 
 from the fulcrum is 25 inches, and the distance of the centre of 
 the valve from the fulcrum is 5 inches. How far from the ful- 
 crum must the valve be placed, in order that the lever may open 
 at a pressure of 100 lbs.? 
 
 Area of valve, 7.07 square inches. 
 
 (1) 10 times 25 is 250 ; (2) 2 times 5 is 10 ; (3) the product of 
 7.07, 100, and 5, is 3535. Adding togetlier products (1) and (2), 
 we have as their sum 260 ; subtracting this from 3535, the third 
 product, we have 3275. Dividing this difference by 100, the 
 weight of the ball, we have 32.75, or 32f inches as the distance 
 from fulcrum to ball. 
 
 To find ichat diameter a safety-valve must have, the other ixirts be- 
 ing known to open at a given steam pres.szire. Multiply (1) the weight 
 of the ball by its horizontal distance from the fulcrum; (2) the 
 weight of the lever by the horizontal distance of its centre of 
 gravity from the fulcrum ; (3) the weight of the valve by the 
 horizontal distance of its centre from the fulcrum ; (4) the pres- 
 svtre of steam in pounds per square inch by the horizontal dis- 
 tance of the valve from the fulcrum, and by the number 0.7854. 
 Add together the first three products, divide their sum by the 
 fourth product, and take the square root of the quotient. 
 
 Example. — Weight of ball, 00 lbs. ; lever, 7 lbs. ; valve, 3 lbs. 
 Distances from fulcrum : ball, 30 inches ; centre of gravity of 
 lever, 16 inches ; centre of valve, 3 inches. Pressure of steam, 
 70 lbs. per square inch. What should be the diameter of the 
 valve ? 
 
 (1) The product of 60 and 30 is 1800 ; (2) the product of 7 and 
 16 is 112 ; (3) the product of 3 and 3 is 9 ; (4) the product of 70, 
 3, and 0.7854 is 164.934. The sum of the first three products, 
 1800, 112, and 9, is 1921. Dividing this sum by 164.934 (the 
 fourth product), we have 11.647 inches. The square root of this 
 number is 3.41 -i- inches, which by the rule is the required dia- 
 meter of the valve. B. 
 
 Valve, To find the angle of bevel of a. — This is the angle of 
 inclination /c a, or e d h, to a vertical line. Make the following 
 measurements : (1) greatest diameter, g h, of valve, in inches ; 
 (2) least diameter, a h, of valve, in inches ; (3) depth, a k, of 
 valve, in inches. Divide the difference of the greatest and least 
 
108 
 
 ENGINEEKING. 
 
 diameters by tlie depth of seat. Find the angle whose tangent is 
 nearest this quotient, in the accompanying table of tangents. 
 
 C d 
 
 Table of Tangents from 20° to 50°. 
 
 Example. — The greatest and least diameter of a valve are 
 4 G-10 and 4 inches, respectively, and the depth is \ inrli. Wliat 
 is the bevel 'i 
 
 (Jreati'st diameter 4.(i 
 
 Least diameter 4. 
 
 2)0. (J 
 
 0.5)0.3 
 
 Tangent of angl<' of incliimtion O.G 
 
 From tin- tablf, it appears tliiit tlic angii! corresponding to this 
 is nearly lil . 1^- 
 
 ValvK, To liiid tlif arrii of (>|iciiiiii,', in S(|iiiur iiiciii'.s, of a, 
 due to a given lift. — ('/) VViicn ilir lift <>f tin' vulve is equal 
 
ENGINEERING. 109 
 
 or to less than the depth of seat : Find the product of (1) the 
 diameter of the valve, in inches ; (3) the lift, in inches ; (3) the 
 sine of the angle of bevel of the valve, and (4) 3.1416. Add this 
 to the product of (1) the square of the lift, in inches ; (2) the 
 square of the sine of angle of bevel of the valve ; (3) the cosine 
 of the angle of bevel of the valve, and (4) 3.1416. 
 
 (6) When the lift of the valve is greater than the depth of 
 seat : Find the product of (1) the diameter of the valve, in 
 inches ; (2) the depth of seat, in inches ; (3) the sine of the angle 
 of bevel of the valve, and (4) 3.1416. Find the product of (1) 
 the square of the depth of seat, in inches ; (2) the square of the 
 sine of the angle of bevel of valve ; (3) the cosine of the angle 
 of bevel of valve, and (4) 3.1416. Find the product of (1) the 
 diameter of the valve, in inches ; (2) the difference between the 
 lift and the depth of seat, in inches, and (3) 3.1416. Take the 
 sum of these three products. 
 
 Example. — The diameter of a valve is 4 inches, the bevel is 35°, 
 and the depth of seat ^ of an inch. What is the area of open- 
 ing for a lift of f of an inch ? 
 
 The product of 4, 0.25, 0.574 (the sine of 35=), and 31416 is 
 1.8. 
 
 The product of the square of 0.25, the square of 0.574, 0.819, 
 (the cosine of 35°), and 3.1416 is 1.85. 
 
 The product of 4, 0.125 (the diflference between the lift and 
 depth of seat), and 3.1416 is 1.57. 
 
 The sum of 1.8, 1.85, aad 1.57 is 3.42 square inches, the area 
 of opening required, B. 
 
 BELTS, PULLEYS, AND SHAFTING. 
 
 Belt-Holes, Laying out, through floors.— If a belt is to be 
 carried from a pulley on an overhead shaft to one on any floor 
 above, tlie distance from centre of lower shaft to ceiling— under 
 side of floor — should be measured and noted ; then the thickness 
 of floor ; next the distance between top of floor and centre of 
 upper shaft. If one pulley or shaft is directly over the other, 
 the size of pulleys and width of belt being known, you have all 
 the data necessary if you measure the distance of one shaft 
 from the wall of building, which is done by dropping a plummet 
 from centre of shaft or diameter of pulley, and measuring to the 
 wall from that point. From these data, whether the two shafts 
 are in the same vertical plane, whether the diameters of the pul- 
 leys are equal, and whether the belt is to be carried through one, 
 two, three, or even four floors or not, the intelligent mechanic can 
 lay out a diagram that will enable him to cut his belt-holes ac- 
 curately. The diagram may be laid out full-size on a swept 
 floor, or, on a reduced scale, on a board or sheet of paper. ]SIea- 
 sures thus made can easily be transferred to the floor through 
 which the holes are to be made. 
 
110 ENGINEERING. 
 
 BELT-LACixa, Eel-pkin. — A mill-owner says : " Eel-skins 
 make the best possible strings for lacing belts. One lace will 
 outlast any belt, and will stand wear and liard usage wliere 
 hooks or any other fastenings fail. Our mill being on the bank 
 of the river, we keep a net set for eels, which, when wanted, are 
 taken out in the morning and skinned, and the skins are stuck on 
 a smooth board. When dry, we cut them in two strings, making 
 the eel-skin, in three hours from the time the fish is taken from 
 the water, travel in a belt." 
 
 Belt-Lacings, Holes for. — The strain on belts is always in the 
 direction of their length, and therefore holes cut for the reception 
 of lacing slioiild be oval (the long diameter in line with the 
 belt). In ])utting or meeting belts, the crossings of the lacings 
 should be on the outside. 
 
 Belt passinc; over t'wo Pui^leys, To find the length of a. — 
 Measure the distance between the centres of the pulleys, the 
 diameters of the pulleys, and the thickness of the belt. Add the 
 thickness of the belt to the diameter of a pulley, and this gives 
 the effective diameter. Half this is the effective radius, and it 
 is to be noted that the effective radius, or tlu' effective diameter, 
 of a pulley should generally be used in all calculations relating 
 to belts and pulleys. In making such calculations, care must be 
 taken, also, to liave all the dimensions in the same unit, feet or 
 inches. In general, it is well to reduce all dimensions to feet. 
 
 To illustrate the ])receding remarks, suppose that the diame- 
 ter of a pulley is 10 inches, and that the thickness of the belt 
 passing over it is f of an incli. What is the effective radius, in 
 feet? Ati.s. The effective diameter is lOg inches ; hence the effec- 
 tive radius is o.^*,; inches. 5 inches is 0.417 ft. ,'',, of an inch is 
 0.010 ft. Hence 5,=^,; inches is 0.433 ft. 
 
 There are two cases to be considered, one in which the belt ia 
 crossed, and the other in which it is open. 
 
 To find the length of a cronxed belt pnssiDf/ orrr tiro judlci/s : 
 
 (1) Divide the sum of the radii of the two pulleys by the dis- 
 tance between their centres, and lind from the table of factors the 
 factor corres|)onding to this quotient. 
 
 (2) Multii)ly the factor so found by the sum of the radii. 
 
 (3) Multiply the sum of the radii by the number 3.141G. 
 
 (4) Siil)tiart tins sijuare of the sum of the radii from tlu; 
 8(juare of the distance Ix-twcen centres, and take the s(|uare root 
 of the remainder. Multiply tlie (juantity so obtaiiu'd liy 2. 
 
 (5) Take tlie sum of the quantities obtained by (2), (3), and (4). 
 Krampfr. — Tlu; radius of one pulley is 42 inches, of the other 
 
 3(» ; tlie distance between centres of pulleys is 12 feet, and the 
 tliickness of tlie lielt is \ of an imli ; rei|iiiir(l, the length of tlu^ 
 belt. 
 
 'I'iie efff'ctive radii an; 3.51 fi^rt and 3.01 feet. 
 
 (1) Sum of radii, 0.520. Distaiwe betwi-en centn^s, 12. Quo- 
 tient of first (|uantity divided by second, 0.51. Factor in talih: 
 I'orrespnnding lo this quotient, 1.141. 
 
 (2) i.ni innitii)iied hy i\.r,':>, 7.430 t . 
 
 (3) 0.541 multipli.-d by 3. 1.41(..20.4H3 + . 
 
ENGINEERING. 
 
 Ill 
 
 (4) Square of distance between centres 144. 
 
 Square of sum of radii. . 42.51 
 
 Difference 101.49 
 
 Square root of difference, 10.074 + . 10.074 multiplied by 2, 
 30.148. 
 
 ^ (5) Sum of 7.439, 20.483. and 20.148, 48.07 feet, or 48 feet and 
 U of an inch, length of belt required. 
 
 Table of Factors for Determining the Length of Belts. 
 
 Quotient. 
 
 ! 
 
 Factor. ' 
 
 Quotient. 
 
 Factor. 
 
 0.01 
 
 0.020 
 
 0.35 
 
 0.716 
 
 0.02 
 
 0.040 1 
 
 0.36 
 
 0.737 
 
 0.03 
 
 0.060 i 
 
 0.37 
 
 0.758 
 
 0.04 
 
 0.080 ' 
 
 0.38 
 
 0.780 
 
 0.05 
 
 0.100 
 
 0.39 
 
 0.802 
 
 0.06 
 
 0.120 
 
 0.40 
 
 0.823 
 
 0.07 
 
 0.140 
 
 0.41 
 
 0.845 
 
 0.08 
 
 0.161 
 
 0.42 
 
 0.867 
 
 0.09 
 
 180 
 
 0.43 
 
 0.890 
 
 0.10 
 
 0.201 
 
 0.44 
 
 0.912 
 
 0.11 
 
 0.220 
 
 0.45 
 
 0.934 
 
 0.12 
 
 0.241 
 
 ! 0.46 
 
 0.956 
 
 0.13 
 
 0.261 
 
 0.47 
 
 0.979 
 
 0.14 
 
 0.281 
 
 0.48 
 
 1.002 
 
 0.15 
 
 0.301 
 
 0.49 
 
 1.025 
 
 0.16 
 
 322 
 
 i 0.50 
 
 1047 
 
 0.17 
 
 0.342 
 
 ; 0.51 
 
 1.070 
 
 0.18 
 
 0.362 
 
 0.52 
 
 1.094 
 
 0.19 
 
 0.383 
 
 0.53 
 
 1.118 
 
 0.20 
 
 0.403 
 
 0.54 
 
 1.141 
 
 0.21 
 
 0.424 
 
 0.55 
 
 1.165 
 
 0.22 
 
 0.444 
 
 0.56 
 
 1.189 
 
 0.23 
 
 0.464 
 
 i 0.57 
 
 1.214 
 
 0.24 
 
 0.485 
 
 1 0.58 
 
 1.238 
 
 0.25 
 
 0.506 
 
 ' 0.59 
 
 1.262 
 
 0.26 
 
 0.527 
 
 0.60 
 
 1.287 
 
 0.27 
 
 0.547 
 
 0.61 
 
 1.312 
 
 0.28 
 
 0.568 
 
 0.62 
 
 1.338 
 
 0.29 
 
 0.589 
 
 . 0.63 
 
 1.364 
 
 0.30 
 
 0.610 
 
 0.64 
 
 1.389 
 
 0.31 
 
 0.631 
 
 0.65 
 
 1.415 
 
 0.32 
 
 0.652 
 
 ' 0.66 
 
 1.443 
 
 0.33 
 
 0.673 
 
 i 0.67 
 
 1.469 
 
 0.34 
 
 0.694 
 
 0.68 
 
 1.496 
 
 Quotient. 
 
 Factor. 
 
 0.69 
 
 1.533 
 
 0.70 
 
 1.551 
 
 0.71 
 
 1.580 
 
 0.72 
 
 1.608 
 
 0.78 
 
 1.637 
 
 0.74 
 
 1.666 
 
 0.75 
 
 1.696 
 
 0.76 
 
 1.727 
 
 0.77 
 
 1.758 
 
 0.78 
 
 1.790 
 
 0.79 
 
 1.822 
 
 0.80 
 
 1.855 
 
 ! 0.81 
 
 1.888 
 
 ; 0.82 
 
 1.923 
 
 ' 0.83 
 
 1.958 
 
 I 0.84 
 
 1.995 
 
 0.85 
 
 2.033 
 
 0.86 
 
 2.071 
 
 0.87 
 
 2.111 
 
 0.88 
 
 2.152 
 
 0.89 
 
 2.195 
 
 0.90 
 
 2.240 
 
 0.91 
 
 3.387 
 
 0.92 
 
 2.336 
 
 0.93 
 
 3.389 
 
 0.94 
 
 2.446 
 
 0.95 
 
 2.507 
 
 0.96 
 
 2.574 
 
 0.97 
 
 2.651 
 
 0.98 
 
 2.743 
 
 0.99 
 
 2.859 
 
 1.00 
 
 3.143 
 
 - 
 
 To find the length of an open belt passing orer tiro pullei/s : 
 (1) Divide the difference of the radii by the distance between 
 
112 ENGINEERING. 
 
 centres, and find fro-.u the table of factors the factor correspond- 
 iiig to this quotient. 
 
 {2) Multiply the factor so found by the difference of the radii. 
 
 (3) Multiply the sum of the radii by the number 3.1410. 
 
 (4) Subtract the square of the difference of the radii from the 
 square of the distance between centres, and take the square root 
 of the remainder. Multiply the quantity so (obtained by 2. 
 
 (5) Take the sum of the quantities obtained by (3), (3), and (4). 
 It will be observed that these rules require only simple arith- 
 metical operations. 
 
 Example. — Given, diameter of driving-wheel, 36 inches; of 
 driven wheel, 9 inches ; distance between centres, 5 feet ; thick- 
 ness of belt, \ of an inch ; what is the length of tlie bellV 
 
 Effective radii, 1.505 and 0.3S0 feet. (1) Difference of radii, 
 1.125. Distance between centres, 5. Quotient, 0.33. Factor in 
 table corresponding to this quotient, 0.404. (3) 0.404 multiplied 
 bv 1.135, 0.533. (3) Sum of radii, 1.885. 1.885 multiplied by 
 3.1416, 5.933. 
 
 (4) Square of distance between centres 35. 
 
 Square of difference of radii 1.366 
 
 Difference 33.734 
 
 Square root of difference, 4.873. 4.873 multiplied by 3, 9.744. 
 (5) Sum of 0.533, 5.933, and 9.744, 16.188 feet, or 16 feet 2^ 
 inches, length of belt. B. 
 
 Belts, Power transmitted by leatlier. — By the aid of the ac- 
 companying tables, now ])ubli8h(;d for the first time, it will be 
 easy for any one to ascertain the amount of power that can be 
 safely transmitted by good leather belts under ordinary circum- 
 stances. It is scarcely necessary to add that the power trans- 
 mitted by a belt in any special case can only be ascertained by 
 experiment. All that can b(! done by the most elaborate rules is 
 to show what power ought io be transmitted if a belt is properly 
 arranged. The tables and accompanying rules will be useful, 
 therefore, in calculations of the widih of belt retjuired to do a 
 definite amount of work under given circumstanc^^s. With 
 these preliminary explanations, the use of the tables will be 
 illustrated. 
 
 I. Other tMiifjs heiiuj cfiuid, the power trnnstnitted hi/ a belt de- 
 pends upon the arc of raittwt and the xpeed <>f the belt. 
 
 II. To find the arc of contact between a belt and a pulley, by the 
 aid, of the neeonipanyliKj table. 
 
 Firnt \fethod. — .Measure the liMigth of tin- portion of th(^ cir- 
 ciiiiifcri'iicc of tin; ])ii]lcy that is in contact with the belt, and 
 tbe diamclcr of the pulh^y. Divide; the first measurement by the 
 radius of the ])ulley, which gives the length of the arc of contact 
 for a circle wliose radius is I. Mud tlic nuinbi-r nearest to this 
 in the column of t!ie talile liiMdrd " i>c'iii:tli of arc for a radius 
 of 1," and till- rc(juirrd imglc will i)r found in tlii; same liori- 
 zo.ital lint' of tin; next column, to the UdV, Invaded " Arc of con- 
 tact. " 
 
ENGINEERING. 
 
 113 
 
 lule for Finding the Are of Contact of a Belt loith a Pulley. 
 
 El 
 
 Both pulleys, crossed belt, and 
 large pulley, open belt. 
 
 Small pulley, open belt. 
 
 < 
 
 z 
 
 O 
 
 Arc of contact. 
 
 Length of arc for 
 a radius of 1. 
 
 Arc of contact. 
 
 Length of arc for 
 a radius of 1. 
 
 0.00 
 
 180° 
 
 3.142 
 
 180° 
 
 3.142 
 
 .01 
 
 181" 
 
 3.162 
 
 179° 
 
 3.122 
 
 .02 
 
 182° 
 
 3.182 
 
 178° 
 
 3.102 
 
 .03 
 
 183° 
 
 3.202 
 
 177° 
 
 3.082 
 
 .04 
 
 185° 
 
 3.222 
 
 175° 
 
 3.062 
 
 .05 
 
 186° 
 
 3.242 
 
 174° 
 
 3.042 
 
 .06 
 
 187° 
 
 3.262 
 
 173° 
 
 3.022 
 
 .07 
 
 188° 
 
 3.282 
 
 172° 
 
 3.002 
 
 .08 
 
 189° 
 
 3.303 
 
 171° 
 
 2.981 
 
 .09 
 
 190° 
 
 3.322 
 
 170° 
 
 2.962 
 
 .10 
 
 192° 
 
 3.343 
 
 168° 
 
 2.941 
 
 .11 
 
 193° 
 
 3.362 
 
 167° 
 
 2.922 
 
 .12 
 
 194° 
 
 3.383 
 
 166° 
 
 2.901 
 
 .13 
 
 195° 
 
 3.403 
 
 165° 
 
 2.881 
 
 .14 
 
 196° 
 
 3.423 
 
 164° 
 
 2.861 
 
 .15 
 
 197° 
 
 3.443 
 
 163° 
 
 2.841 
 
 .16 
 
 198° 
 
 3.464 
 
 162° 
 
 2.820 
 
 .17 
 
 200° 
 
 3.484 
 
 160° 
 
 2.800 
 
 .18 
 
 201° 
 
 3.504 
 
 159° 
 
 2.780 
 
 .19 
 
 202° 
 
 3.525 
 
 158° 
 
 2.759 
 
 .20 
 
 203° 
 
 3.545 
 
 157° 
 
 2.739 
 
 .21 
 
 204° 
 
 3.566 
 
 156° 
 
 2.718 
 
 .22 
 
 205° 
 
 3.586 
 
 155° 
 
 2.698 
 
 .23 
 
 207° 
 
 3.606 
 
 153° 
 
 2.678 
 
 .24 
 
 208° 
 
 3.627 
 
 152° 
 
 2.657 
 
 .25 
 
 209° 
 
 3.648 
 
 151° 
 
 2.636 
 
 .26 
 
 210° 
 
 3.669 
 
 150° 
 
 2.615 
 
 .27 
 
 211° 
 
 3.689 
 
 149° 
 
 2.595 
 
 .28 
 
 213° 
 
 3.710 
 
 147° 
 
 2.574 
 
 .29 
 
 214° 
 
 3.731 
 
 146° 
 
 2.553 
 
 .30 
 
 215° 
 
 3.752 
 
 145° 
 
 2.532 
 
 .31 
 
 216° 
 
 3.773 
 
 144° 
 
 2.511 
 
 .32 
 
 217° 
 
 3.794 
 
 143° 
 
 2.490 
 
 .33 
 
 219° 
 
 3.S15 
 
 141° 
 
 2.469 
 
 .34 
 
 220° 
 
 3.836 
 
 140° 
 
 2.448 
 
 .35 
 
 221° 
 
 3.858 
 
 139° 
 
 2.426 
 
 .36 
 
 222° 
 
 3.879 
 
 138° 
 
 2.405 
 
 .37 
 
 223° 
 
 3.900 
 
 137° 
 
 2.384 
 
 .38 
 
 225° 
 
 3.922 
 
 135° 
 
 2.362 
 
 .39 
 
 226° 
 
 3.944 
 
 134° 
 
 2.340 
 
 .40 
 
 227° 
 
 3.965 
 
 133° 
 
 2.319 
 
 .41 
 
 228° 
 
 3.987 
 
 132° 
 
 2.297 
 
 .43 
 
 230° 
 
 4.009 
 
 130° 
 
 2.275 
 
 .43 
 
 231° 
 
 4.032 
 
 129° 
 
 2.252 
 
 .44 
 
 232° 
 
 4.054 
 
 128° 
 
 2.230 
 
 .45 
 
 234° 
 
 4.076 
 
 126° 
 
 2.208 
 
 .46 
 
 235° 
 
 4.098 
 
 125° 
 
 2.186 
 
 .47 
 
 2:^6° 
 
 4.121 
 
 124° 
 
 2.163 
 
 .48 
 
 237° 
 
 4.144 
 
 12:}° 
 
 2.140 
 
 .49 
 
 239° 
 
 4 167 
 
 121° 
 
 2.117 
 
 .50 
 
 240° 
 
 4.189 
 
 120° 
 
 2.095 
 
114 
 
 ENGINEEKING. 
 
 Table for Finding the Arc of Contact of a Belt tcitJi a Pulley. 
 
 (Continued.) 
 
 ^ 
 
 Both pulleys, crossed belt, and 
 large pulley, open belt. 
 
 Small pullej% open belt. 
 
 1 CONSTAK 
 
 Arc of contact. 
 
 Length of arc for 
 a radius of 1 . 
 
 Arc of contact. 
 
 Length of arc tt 
 a radius of 1. 
 
 .51 
 
 241° 
 
 4.212 
 
 119° 
 
 2.072 
 
 .52 
 
 243° 
 
 4.236 
 
 117° 
 
 2.048 
 
 .53 
 
 244° 
 
 4.260 
 
 116° 
 
 2.0^ 
 
 .54 
 
 245° 
 
 4.283 
 
 115° 
 
 2.001 
 
 .55 
 
 247° 
 
 4.307 
 
 113° 
 
 1.977 
 
 .56 
 
 248° 
 
 4.331 
 
 112° 
 
 1.953 
 
 .57 
 
 250° 
 
 4.356 
 
 110° 
 
 1.928 
 
 .58 
 
 251° 
 
 4.380 
 
 109° 
 
 1.904 
 
 .59 
 
 252° 
 
 4.404 
 
 108° 
 
 1.880 
 
 .60 
 
 254° 
 
 4.429 
 
 106° 
 
 1.855 
 
 .61 
 
 255° 
 
 4.454 
 
 105° 
 
 1.830 
 
 .62 
 
 257° 
 
 4.480 
 
 103° 
 
 1.804 
 
 .63 
 
 258° 
 
 4.506 
 
 102° 
 
 1.778 
 
 .64 
 
 260° 
 
 4.531 
 
 100° 
 
 1.753 
 
 .65 
 
 261° 
 
 4.557 
 
 99° 
 
 1.727 
 
 .66 
 
 263° 
 
 4.585 
 
 97° 
 
 1.699 
 
 .67 
 
 264° 
 
 4.611 
 
 %° 
 
 1.673 
 
 .68 
 
 266° 
 
 4.638 
 
 94° 
 
 l.WO 
 
 .69 
 
 267° 
 
 4. 065 
 
 93° 
 
 1.G19 
 
 .70 
 
 269° 
 
 4.693 
 
 91° 
 
 1.5'Jl 
 
 .71 
 
 271° 
 
 4.722 
 
 89° 
 
 1.562 
 
 .72 
 
 273° 
 
 4. 750 
 
 88° 
 
 l.o:i4 
 
 .73 
 
 27'1° 
 
 4.779 
 
 86° 
 
 1..505 
 
 .74 
 
 275° 
 
 4.808 
 
 85° 
 
 1.476 
 
 .75 
 
 277° 
 
 4.8:^8 
 
 83° 
 
 1.446 
 
 .76 
 
 270° 
 
 4.86«J 
 
 81° 
 
 1.415 
 
 .77 
 
 281° 
 
 4.900 
 
 79° 
 
 1.384 
 
 .78 
 
 283° 
 
 4.932 
 
 77° 
 
 1.3.->2 
 
 .79 
 
 284° 
 
 4.9&1 
 
 76° 
 
 1.320 
 
 .80 
 
 286° 
 
 4.9!>7 
 
 74° 
 
 1.387 
 
 .81 
 
 288° 
 
 B.CCiO 
 
 72° 
 
 1.2.54 
 
 .82 
 
 290° 
 
 5.(Hi5 
 
 70° 
 
 1.319 
 
 83 
 
 292° 
 
 5.KX) 
 
 68° 
 
 I.IM 
 
 .84 
 
 294° 
 
 5.137 
 
 6<i° 
 
 1.147 
 
 .85 
 
 296° 
 
 5.174 
 
 M° 
 
 1.110 
 
 .86 
 
 299° 
 
 5.213 
 
 61° 
 
 1 (171 
 
 .87 
 
 801O 
 
 5.2.'>3 
 
 59° 
 
 1 ();il 
 
 .88 
 
 808° 
 
 6.294 
 
 57° 
 
 (1 '.190 
 
 .89 
 
 306° 
 
 5..S:}7 
 
 54° 
 
 0.9-17 
 
 .90 
 
 308° 
 
 5.382 
 
 .'J2° 
 
 0.902 
 
 91 
 
 311° 
 
 5.429 
 
 49° 
 
 0.8.-)5 
 
 .92 
 
 314° 
 
 5.478 
 
 46° 
 
 0.8(16 
 
 .98 
 
 817° 
 
 5.581 
 
 48° 
 
 o.7.'>:i 
 
 .94 
 
 820° 
 
 5.588 
 
 40° 
 
 0.(i9C> 
 
 .95 
 
 824° 
 
 5.(M9 
 
 :«i° 
 
 (t.(kJ5 
 
 .96 
 
 888° 
 
 5.716 
 
 32° 
 
 ()..")C)8 
 
 .97 
 
 832° 
 
 5.793 
 
 28° 
 
 0.491 
 
 .98 
 
 837° 
 
 5.885 
 
 iSl" 
 
 0:VM< 
 
 .99 
 
 844° 
 
 li.OOl 
 
 1(1" 
 
 (l.-JKJ 
 
 1.00 
 
 aio° 
 
 6.284 
 
 (I" 
 
 (KM) 
 
ENGLXEERIXG. 115 
 
 Example. — Suppose the length of tlie circumference of a pul- 
 ley in contact with a belt is 8A feet, and the diameter of the 
 pulley is 4 feet. The quotient arising from dividing 8^ by 2 (the 
 radius of the pulley) is 4.25, and the number in the table nearest 
 to this is 4.26, showing that the required arc of contact is about 
 244°. 
 
 [It is to be noted that, in calculations of this kind, the effective 
 radius of the pulley should be used (see page 110), and all dimen- 
 sions must be referred to the same unit of measurement.] 
 
 Second Method. — Measure the effective diameters of both pul- 
 leys, and the distance between their centres. There are two 
 cases to be considered : 
 
 (a) To find the arc of contact for a crossed belt. 
 
 Divide the sum of the radii of the two pulleys by the distance 
 tween their centres ; find in the column of constants the nearest 
 number to the quotient, and pick out the corresponding angle. 
 
 Example. — Diameter of driven pulley, 20 inches ; of driving 
 pulley, 24 ; distance between centres, 8 feet. What is the arc of 
 contact on each pulley of a crossed belt passing over them ? Sum 
 of radii, 1.8333 feet. 1.8333 divided by 8 is 0.23, nearly. From 
 the table, it appears that the angle required is 207\ 
 
 (b) To find the arc of contact for an open belt. 
 
 Divide the difference of the radii of the two pulleys by the 
 distance between their centres, and find the angles corresponding 
 to the constant nearest to the quotient, in the table. 
 
 Example. — In the case of an open belt passing over two pul- 
 leys, the following dimensions are given : Diameter of driving 
 pulley is 5.25 feet; diameter of driven pulley is 3.5 feet; dis- 
 tance between centres is 9 feet. The difference of radii (0.875) di- 
 vided by 9 is 0.097-]-. Neare.st constant in table, 0.1, correspond- 
 ing to an angle of contact of 192' on the driving, and 168° on the 
 driven pulley. 
 
 [These rules are founded on the assumption that the belt is 
 drawn perfectly tight between the pulleys. Where there is much 
 deviation from this, in practice, it is better to emjjloy the first 
 method.] 
 
 III. To find the speed of a helt, infect, per minute. 
 
 Multiply the diameter of either imlley, in feet, by 3.1416 times 
 the number of revolutions that it makes per minute. 
 
 Example.— \ belt passes over a pulley that is 3 feet in diame- 
 ter, and makes 200 revolutions a minute". The speed of the belt 
 is the product of 3, 3.1416, and 200, or about 1885 feet per 
 minute. 
 
 ly. To find the potcer that can he safely transmitted by a good 
 leather belt of given width, passing over smooth iron jniUeys, and 
 running at a given speed, the arc of contact beinq als', given. 
 
 This IS determined by means of the second table Find the 
 horse-power for a belt one inch in width, for the nearest arc of 
 contact in the table, and the nearest speed of belt, and multinlv 
 this by the width of the belt. If the belt is open, and the pul- 
 leys have different diameters, take the angle of contact made by 
 the belt with the smaller pulley. 
 
116 
 
 ENGINEERING. 
 
 
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ENGINEERING. 
 
 119 
 
 Example. — What horse-power can be transmitted by a leather 
 belt 10 inches wide, making an angle of contact of 80' with the 
 smaller of the two pulleys over which it passes, and having a speed 
 of 2400 feet per minute? Ans. — Horse-power for a belt 1 inch 
 wide and 2000 feet speed is 1.802 ; horse-power for a belt 1 inch 
 wide and 400 feet speed is 0.3G0 ; therefore, by addition, horse- 
 power of 1 inch belt for 2400 feet speed is 2.162;" and for 10 horse- 
 power, 10 times 2.162, or 21.62. 
 
 V. 2'f find the icidth of belt necessary to transmit a ffiven, 
 amount of poicer for a given are of contact and given speed in 
 feet per minute. 
 
 Find the power transmitted by a belt 1 inch wide, and divide 
 the given power by this amount. 
 
 Example. — An open belt passes over two pulleys having dia- 
 meters of 4 and 6 feet respectively, and the former makes 300 
 revolutions a minute. The distance between the centres of the 
 pulleys is 15 feet. What should be the width of a belt to trans- 
 mit 50 horse-power under these circumstances ? Speed of belt 
 in feet per minute, 3770 ; arc of contact of belt Avith smaller 
 pulley, 172^ ; horse-iX)wer transmitted by a belt 1 inch wide, 
 under conditions in table nearest to those determined above {i.e. , 
 for arc of contact of 170", and speed of 3800), 5.488. Required 
 width of belt, 50 divided by 5.488, or a little over 9 inches. 
 
 VI. In the use of a leather belt, it is best to run it with the 
 grain side next to the pulleys, or in exactly the opposite way 
 from that in which the hide was worn by the animal that was 
 the original proprietor of the leather. 
 
 VII. Lace-leather is better than hooks for fastening the ends 
 of a belt togetlier ; and a still better method, after a belt has be- 
 come sufficiently stretched by use, is to rivet the ends together 
 with long laps. In lacing a belt of any considerable size, make 
 two rows of holes in each belt end, and" put in double lacing. 
 
 VIII. A belt that is made of good material, and is of ample 
 size, will last for many years, if kept clean, and prevented from 
 becoming dry and hard by the use of neat's-foot oil. It is poor 
 economy to buy a belt whose chief recommendation is its small 
 first cost. It is also a bad plan to use a belt that is just suflicient 
 to transmit the power when Very tightly strained. B. 
 
 CORNER-TURNED BELT. 
 
 Belts, Corner-turned, Device for.— The two shafts placed at 
 right angles, as shown in the engraving, carry the belt from A or 
 
120 
 
 ENGINEERING. 
 
 B, passing around two flanged pulleys or guides, C, turning loose- 
 ly on a fixed upright shaft, and sustained in position bj^ a collar 
 under the hub of each. It is possible to run pulleys by this de- 
 vice which not only have varying diameters, but the shafts of 
 which are on different levels ; but the results are not so good, 
 owing to unequal strain on the belt. It is better to confine this 
 method to shafts on the same level, and to pulleys of equal dia- 
 meter, and the useful limit of angle of shafts is that of 45°, or 
 less. A greater or more obtuse angle is better run by means of 
 guides on two uprights. 
 
 Belts, Coupling. — In Fig. 1, A, B, C, and D are pieces of No. 
 16 sheet-iron, riveted to the ends of the belt ; E E are hooks, 
 shown in the natural size in Fig. 2 , riveted to B. After the belt 
 
 ■lUI'I.lNC r.Kl.TS. 
 
 is laid over tin; pulleys, tin; hooks, F and (J, of the lever, sliown 
 in Fig. 8, are placed in the holes at C and D. Now the two ends 
 of the belt are drawn together by the lever, H, and the hooks. 
 E, are i)ut in their places at A. Then the lever is taken out, 
 leaving the joint finished. By this nietliod, two men can set and 
 couple a belt in the least possible time, obtaining an eff«;ctual 
 joint, which will never allow the belt to run out of true, or to re- 
 verse. 
 
 Belts, Increasing the conveying fore*- of. — Adding to the width 
 of a l)e.lt and of the faces of the jiiilleys increases immensely the 
 ])ower of conveying force. A wide belt is always better than a 
 narrow one, strained to its utmost ca|)acity. 
 
 Bklts, Mending. — Lay llii' two I'nds of the l^(;lt exactly even, 
 witli tlie insi(h'S together, and piincli one straiglit row of holes 
 across tlie end, driving the piincli through both i)leceH so that the 
 
ENGINEERING. 121 
 
 holes may correspond. Now take your lace, pointed at both 
 ends, and pass the points in opposite directions through the first 
 hole, still keeping the two ends of the belt together as when 
 punched, and draw the loop tight, observing to keep the ends of 
 equal length. Pass the points through the second hole, and so 
 proceed to the last ; then tie the ends over the edge of the belt, 
 and the job is done. A belt can thus be mended in half the time 
 and with half the length of lacing required in the usual way ; and 
 wlien the belt is subjected to heavy strains or slipping, it will 
 wear ten times as long, as the lace never touches the pulley- 
 faces. Of course the plan is not applicable when both sides of a 
 belt run over pulleys, nor when the projecting ends would strike 
 any thing in their track. 
 
 Belts, Oiling. — The best mode of oiling a belt is to take it 
 from the pulleys, and immerse it in a warm solution of tallow and 
 oil ; after allowing it to remain a few moments, the belt should 
 be immersed in water heated to 100° Fahr., and instantly removed. 
 This will drive the oil and tallow all in, and at the same time 
 properly temper the leather. 
 
 Belts, Rubber, To prevent, slipping on pulleys. — Chalk the 
 pulley when slipping occurs. The presumption is, however, that 
 the belt is either too narrow or too loose. 
 
 Belts, Splicing large. — Cut your belt perfectly square on the 
 ends and to the proper length ; then cut a piece of belt of the 
 same width and thickness, about 3 feet long. Bring the ends of 
 the belt together, and put the short piece on the back of the 
 joint, or outside, and bolt the belt and piece together with what 
 are known as elevator- bolts, used for fastening the buckets to 
 elevator-bands_. The tools required are a brace and bit to bore 
 the holes, and a small pair of blacksmith's tongs to tighten up the 
 nuts with. 
 
 Belts, Testing leather for. — A. cutting of the material about 
 0.03 of an inch in thickness is placed in strong vinegar. If the 
 leather has been thoroughly acted upon by the tanning, and is 
 lience of good quality, it will remain, for months even, immersed 
 without alteration, simply becoming a little darker in color. But, 
 on the contrary, if not well impregnated by the tannin, the 
 fibres will quickly swell, and, after a short period, become trans- 
 formed into a gelatinous mass. 
 
 Belts, To lay out quarter-twist. — To make holes through 
 floors for the belts, lay out on a floor with chalk-line and train 
 two views of the pulley, or by scale on paper as shown in the an- 
 nexed diagram. B is the belt running in the direction of the 
 arrow on the lower pulley, and C is the belt running in the 
 opposite direction. Therefore, drop a plumb-line, representing 
 the perpendiculars, B and C, and draw the diagonals governed by 
 the diameters of the pulleys, marking the distances a b and c d 
 on the floor. Now, drop a plumb-line from each side of the cen- 
 tre of face of upper pulley to the floor, and from one point, c, 
 
122 EXGIXEERIXG. 
 
 thus found, lay off the distance a h, in a line parallel with the 
 upper shaft, and from the point n in the distance, f d, parallel 
 
 T.AYIMi OIT l^lAltTKI!-TWI>T BEIT-" Tllltorull FI.OOIIS. 
 
 with the lower shaft. ThoHc points are tin- places at which the 
 hok'H should be cut. 
 
 FuKTioN ANi") LrnurcANTs. — Whenever one surface moves 
 uj)on anotlirr, tlic roii^h and iiri)jccfinjf ])oints of tlic f wo sur- 
 face's (wliich always exist, even in tin- siiioofhcst surfaces) op- 
 pose resistiuice to the motion, and tliis resistance is called fric- 
 tion. 
 
ENGINEERING. " 123 
 
 The coefficient of friction is a quantity expressing the ratio of 
 the friction to the pressure. For instance, if the resistance to 
 moving one piece of metal on another is one fifth of the weight of 
 the moving body, the coefficient of friction in this case is one 
 fiftli, or 0.2. Hence, knowing the coefficient of friction, in any 
 given instance, and the weight of the body causing the resist- 
 ance, the amount of friction is foiind by multiplying these two 
 quantities together. 
 
 The work due to or lost on account of friction, in any given 
 time, is found by multiplying the amount of friction of the moving 
 body by the space passed through in the given time. It is cus- 
 tomary to estimate the amount of friction in pounds, to niake the 
 given time one minute, and to measure the distance passed 
 through in that time in feet. The result obtained will then ex- 
 press the number of foot-pounds of work performed per minute 
 in overcoming friction, and this can readily be reduced to horse- 
 power, or any other desired unit of work. It is important to 
 maintain the distinction between the amount of friction and the 
 work of friction. 
 
 The experiments of Coulomb and Morin have demonstrated 
 the following facts in regard to friction : 
 
 That it is proportional to the pressure. 
 
 With some limitations, that it is independent of the area of the 
 surface pressed, and independent of the velocity of motion. 
 
 The limitations are, that the pressure should not be so great as 
 to abrade or wear away the surface rapidly, in which case the 
 friction does not follow the laws enunciated above ; also, that 
 the velocity of motion shall not be so great as to expel the lubri- 
 cant. It is found, for instance, in the case of the journals of car- 
 axles, that they require to be enlarged as the speed increases, in 
 order to prevent the expulsion of the lubricant. The actual bear- 
 ing surface of a journal is usually considered to be the projected 
 area of that journal, or the product of the length multiplied by 
 the diameter. For instance, if a journal is 4 inches in cliameter 
 and 7 inches long, the bearing surface is 28 square inches. 
 
 The pressure per square inch on the bearing surface should 
 not exceed the folloAving limits : 
 
 Velocity of periphery Limiting pressure per sq. in. 
 
 of journal. of Dearing surface. 
 
 1 foot per second 382 lbs. 
 
 2i feet per second 224 " 
 
 5 feet per second 140 " 
 
 It is well known that one of the most common expedients for re- 
 ducing the friction between two rubbing surfaces is to interpose 
 some lubricant, which seems to form a coating to the projecting 
 points, making the whole surface more continuous, and thus les- 
 sening the resistance. At very low pressures and velocities the 
 viscosity of the lubricant occasionally causes the resistance to be 
 increased instead of lessened, but in general the effect of an un- 
 guent is to decrease the friction in quite a large ratio. Careful 
 experiments have Ifeen made with regard to the friction between 
 two surfaces when they were perfectly dry and clean, and when 
 
124 
 
 ENGINEERING. 
 
 different liTbricants were used. In this manner it has been found 
 tliat good oil, such as olive-oil, is one of the best lubricants ; that 
 lard is better than tallow, and that the use of water, instead of 
 lessening the friction, generally increases it. Experiments upon 
 the manner of applying the lubricant show that there is a great 
 advantage in a continual application, so as to keep a film con- 
 stantly interposed between the rubbing surfaces, over the case in 
 which the surfaces are merely kept slightly greasy. Below are 
 given mean values for the coefficient of friction, in cases arising 
 from the sliding of one plane surface upon another, the surfaces 
 being supposed to be true, and, in common language, smooth : 
 
 NATrrEE OP THE SLIDING 
 8UKFACE. 
 
 Wood on wood. 
 Wood on metal 
 Metal on metal 
 
 3 
 
 o 
 
 0.38 
 0.41 
 0.18 
 
 Well lubricated with 
 
 ^ 
 
 p 
 
 0.811 
 
 CO 
 
 o 
 p 
 
 •a 
 
 0.144 
 
 0.20 
 
 0.197 
 
 0.0G4 
 O.OTl 
 
 p, 
 
 «— • 
 o 
 
 p 
 
 0.0710.066 
 
 0.079 
 0.092 
 
 0.076 
 0.075 
 
 P Q, 
 
 O P 
 
 : 3 
 
 : ^ 
 
 : w 
 
 • 5" 
 
 : 3 
 
 0.070 
 
 Tn the case of journals, the coefficient of friction is generally 
 much less than for iihine surfaces. Mean values of this coeffi- 
 cient, both for wood and metals, vary from 0. l.>, when the jour- 
 nal is only slightly unctuous, to 0.05, when there is a continual 
 8U[ pl.V '^f the lubricant. In regard to journal-friction, the amount 
 is independent of the diameter of the journal, but the work re- 
 quired to ovi-rcomo frictiou will of course; be greater with a largo 
 tlian with a small journal, because the distance passed through 
 by the periplu^ry of the journal in a given time will be greater in 
 the former cnse. ^• 
 
 liKi/rs, Testing vulcanized rubber for.— These trials consist in 
 examining the comparative degrees of elasticity and tenacity. 
 Tlie manner in whlcli they are conducted in the French navy ap- 
 pears i)ractical and easily followed. Tiie first test consists in cut- 
 ting from the sheets saTn])les, which are left in a steam-boiler 
 under a pressure of 5 atmospheres for 48 hours. At the end of 
 this time, the pieces shoulil not have lost thisir elasticity. The 
 s])eciineiis may theu be i)la<-ed cm the grating of a valve box, un- 
 d(!r a pressure from above of 85.5 ihs. per .s(|uiire inch, and should 
 witlistand 9100 strokes at the rate of 1(»0 jier minute. Specimens 
 not l)oiled should withstand 17.10;) strokes. Thongs of rubber 
 boiled, and having a section O.ti inch sipuire and a length of 8 
 inches, (ixed between sujjports an<l elonga#d :i.9 inches, should 
 resist, witliout breaking, a further ehmgation of 8 inches, re- 
 
ENGINEERING. 125 
 
 peated 22 times a minute for 24 hours. Thongs not boiled, under 
 the same conditions, should resist for 100 hours. These extra 
 elongations may be easily made by a wheel, to the periphery of 
 which one end of the thong is fastened, while the other extremity 
 may be attached to a support. By turning the wheel, any deter- 
 mined elongation may be given at the rate of from 20 to 25 times 
 per minute. Under the above conditions, bands of first quality 
 rubber, perfectly pure and well vulcanized, break after 180 or 200 
 elongations of 8 times the initial length. Bands cut from pure 
 rubber, but of secondary quality, break after 50 or 60 elongations. 
 Inferior caoutchouc, containing mineral matters or residue of old 
 vulcanized rubber, gives no results at all. 
 
 M. Ogier has investigated the properties of rubber belts made 
 of repeated layers of cloth covered with prepared rubber. Through 
 the adhesive nature of the caoutchouc, the superposed tissues 
 form, after vulcanization, a homogeneous substance, comparable, 
 in M. Ogier's opinion, to the best curried leather. His experi- 
 ments, in order to obtain the coefficient of friction of these belts on 
 cast-iron pulleys, give us results varying from 0.42 to 0.84, as 
 against the coefficient for leather, 0.28. The minimum value cor- 
 responds to canvas and rubber belts Avithout an exterior rubber 
 coating. On pulleys of various forms, the maximum value of the 
 coefficient of friction was found on tliose slightly convex and pre- 
 senting a roughly turned surface, this result being inverse to that 
 obtained with leather belts. Similarly the presence of fatty 
 bodies has an opposite action on the cloth and rubber belts to that 
 which it has on- leather. On covering the former with a light 
 varnish of half olive-oil and half tallow, the adhesion was found 
 to be consideraldy augmented. (1) The resistance to traction of 
 rubber and canvas belts per square millimeter (0.0009 square inch) 
 of section, is at least equal to that of leather belts. (2) This re- 
 sistance per square millimeter is independent of dimensions — 
 length, breadth, or thickness. Such is not the case with leather 
 belts, and therefore preference should be given to rubber belting 
 whenever the conditions of the power to be transmitted necessi- 
 tate the employment of very long, very wide, and very thick 
 belts. (3) From two trials it appears that"the external covering of 
 caoutchouc adds nothing to the resistance, and hence it is advan- 
 tageous to use covered belts which, at equal weights and prices, 
 give a superior resistance. (4) Under the same weight, the elastic 
 elongation of leather belts is double that of rubber ones. The 
 permanent elongation, under a change of 0.55 pound per square 
 millimeter, reached 2 per cent in the former and nothing in the 
 latter. 
 
 Belts, To prevent gnawing of, by rats. — Anoint with castor- 
 oil. 
 
 Belt-Tighteners, To place. — The loss of power occasioned by 
 the use of a tightener, is the power required to bend the belt under 
 that pulley and to drive the pulley. By placing the tightener 
 near the smaller pulley of two of unequal size, there is a greater 
 loss than when it is close to the larger, since the belt requires to 
 be more bent in the former case. The best place, therefore, to 
 
126 
 
 ENGINE EKING. 
 
 put a tightener, is as close to the larger pulley as it can be ar- 
 ranged to have it work satisfactorily. 
 
 UNIVERSAL POINT FOR BOKING-TOOL. 
 
 Hangers, Securing. — If it sliould be required to place a hanger 
 between tiooring-l)ciims, the Hoor to which it is attached sliould 
 be strengthened witli a generous ])icc(' of ])lank. For securing 
 hangers, lag-screws are superior to bolts witli nuts, where there 
 is sufficient thickness of wood. A wooden straiglit-edge, reach- 
 ing from on(! bearing to another, is Ijetter for leveling hangers 
 and boxes tliau a twine, wliidi will sag nior(> or less. Some use 
 short cylinders of iron turned to fit the box, and liaving a central 
 hole drilled longitudinally through them. Tliis is an excellent 
 l)lan, as tlie eye nuiy sight through, ora string be ])assed through 
 to determine the level. Where holes are to be bored through the 
 floor clo.se to a wall, post, or other vertical obstruction, a handy 
 tool, similar to tliat shown in the cut, conu»s into ])lay. It is easi- 
 ly forgi^d, and need not be finished with tli<^ elegance of contour 
 shown. A is one of the yokes, and B the cross ; they art^ seisn 
 united at C. 'i'he shaidv of out' yoke has a tapering s<|uar(! hole 
 to receive a bit or auger, and tin; other is a ta])ering stjuare shank 
 to fit a stock of the bit-l)race. Tlie device is " a universal joint," 
 and can be readily worked at an anglt! of 4/)^. 
 
 IIo'P liKAUiNc; ;\i,AiiM. — A cylindrical box, A, is jji-ovidrd with 
 a jjerforated bottom, H, and i)laced directly over the journal. 
 'i'he box is filled wilh a pre])ared grease which nudts at a certain 
 trmperatnre, to which it must be raised by the shaft becoming 
 hot. As till- coiriiiciiinil iii|Mi(it'M iind c■^;(•ll|les through tln' |p('rforii 
 
ENGINEERING. 
 
 127 
 
 tions, a disk, (", which rests thereon, descends, thereby tilting the 
 lever, D, and so making contact between the plates, E and F. 
 The latter are connected by an electric circuit with a bell which 
 
 HOT-BEARING ALARM, 
 
 sounds when the current is established. The pipe, G, serves for 
 the ordinary lubrication of the journal. It is suggested that this 
 device might be profitably used upon journals not readily acces- 
 sible. 
 
 Pulleys, Balancing.— Swing the pulley on arbors between 
 lathe-centres, and note the position as determined by gravity. On 
 
 CONE XtTLLEYS, FIG. 1. 
 
 the top side, drill and tap two holes, in which seat machine screws 
 with flat heads, the shanks projecting through from the face or 
 
128 
 
 ENGINEERING. 
 
 outer side. Then, by pecurinj^ pieces of iron as weights to this 
 point until the pulley is balanced, the amount necessary to 
 balance the pulley is found. This amount of lead is then melted 
 and cast in a mould formed by clay. The screws serve to hold 
 the lead in place. 
 
 Pulleys, To design cone. — The following rules will enable any 
 one who understands arithmetical operations to make the calcu- 
 lations necessary for designing a set of cone pulleys in such a 
 manner that the belt can be shifted from one pair to another, and 
 be equally tight in every position. There are six cases to be con- 
 sidered 
 
 CONE PULI.EY.1, Fid. 2. 
 
 Case 1. — Crossed belt jxissing over two continuotis cones. (Fig. 1 .) 
 — In this case, it is only necessary to use two similar conical 
 drums, with their large and snuill ends turniHl ojjposite way.s. 
 
 Cask 2. — Crossid belt pasHiittj over tiro stepped eones that are 
 equal and opposite. (Fig. 2.) Draw vertical lines, A B, CD, etc., 
 to tlie axes of tlie pulleys, at a distance apart e(]ual to the face of 
 a pulley. Lay off, on each si(l(M)f tlie axis, distances, ab, ac, e(jual 
 to tlie radius of Ihc largest piilii-y, and d r, d f, e(|ual to tlic radius 
 of tli'i smaJlrst pulley. Draw a siraiglit line, li .M, llnDUtrli i)an(l 
 e, and !S () lliiMugli c and f. 'I'lu- points in which llu-se lines rut 
 the verticals detennini' the radii of tlie intermediate ])ulleys. 
 
 Cask ;{. — (Jros.sed heft pussiiuj orer ain/ tien .ntepped cones. — As- 
 Bume values for the radii of one dri\ ing-pulh-v and the corre- 
 sponding driven pulley. 'I'lieii, for any asHuiiied radius of a 
 
ENGINEERING. 
 
 129 
 
 second driving-pulley, the radius of the driven pulley must have 
 such a value that the sum of these two radii is equal to the sum 
 of the first two. The same must be true for every pair of pulleys 
 in the two stepped cones. 
 
 Example. — Suppose the radius of the first driving-pulley is 15 
 inches, and of the first driven pulley 5 inches. Now, if there are 
 five steps in the driving-cone, having radii of 15, 12, 9, 6, and 3 
 inches respectively, the corresponding steps of the driven cone 
 will have radii of 5, 8, 11, 14, and 17 inches, since the sum of the 
 radii of each pair of pulleys must be equal to the sum of the 
 radii of the first pair, or 20 inches. It will be evident from the 
 foregoing that, in the case of crossed belts, the construction of 
 cone-pulleys is very simple, since it is only necessary to observe 
 the directions given above, no matter what the distance between 
 the centres of driving and driven pulley may be. 
 
 CONE PTTLI/EYS, FIG. 3. 
 
 Case 4. — Open belt passing over two continuous pulleys. (Fig. 3.) 
 
 For this case equal and similar conoids must be used. Assume 
 the largest radius, AF, and the smallest, B D, and calculate, by the 
 rule on page 111, the length of belt required for pulleys with the 
 given radit, the distance, K L, between their centres being given. 
 Then the middle radius, C H, is found by the following rule : 
 
 Subtract twice the distance between centres from the length of 
 the belt, and divide the difference by the number 6.2832. 
 
 Having found the middle radius, draw circular arcs through the 
 points F H D and G I E, thus determining the section of the 
 conoid. 
 
 Example. — Suppose that the largest radius is 24 inches, the 
 
130 
 
 ENGINEERING. 
 
 smallest 6 inches, and the distance between centres of conoids 3 
 feet. What should be the middle radius ? 
 
 First find the length of belt : 3 diminished by 0.5 equals 1.5. 
 This divided by 3 equals 0.5, and the corresponding number in 
 table of factors, page 111, is 1.047— (1). 1.047 multiplied by 1.5 
 equals 1.571 — (2). 2 added to 0.5 equals 2.5, which multiplied by 
 3.1416 equals 7.854 — (3). 3 multiplied by 3 equals 9, which less 
 2.25 equals 6.75. 1.5 multiplied by 1.5 equals 2.25. The square 
 root of 6.75 is 2.6, which multiplied by 2 equals 5.2— (4). The 
 sum of 5.2 and 1.571 and 7.854 equals 14.625, wliich is the length 
 of belt. Then find the middle radius by the preceding rule : 3 
 multiplied by 2 equals 6. 14.625 less 6 equals 8.625, which divid- 
 ed by 6.2832 equals 1.373 feet, or about 16i inches middle radius 
 required. 
 
 co.NK inn.i.KYs, pio. 4. 
 
 Case 5. — Opni hrlt passinr/ over two stepped roncx that are equal 
 and oppositf. — (Fig. 4.) — The construction will be evidtMit from 
 the figure, it only being nece.s.sary to form two continuous conoids, 
 UH explained above, and divide tliciu into the rctjuiri'd number of 
 
 Ht(!p«. 
 
 ("ahkO. — (^)pni, Ixit pasHiiHj iirrr an// tiro ><t(j)/)(<l cdhis. — Th(^ 
 ruUrs for this case, originally demonstrated ])y J. li. Ilenek, are 
 jiresented below in a siniiililied fnrni. Kirst assnme the radii of 
 <me driving-j)ulley and tliu corresponding driven pulley, measure 
 the distance between tlu-ir centres, and find the length of belt re- 
 
ENGINEEKING. 131 
 
 quired. Then assume values for the radii of the successive pul- 
 leys on the driving-cone, and calculate the values of the corre- 
 sponding radii on the driven cone by the following rules : I. Hav- 
 ing assumed the value of one radius, it is first necessary to ascer- 
 tain whether the one to be calculated is larger or smaller. (1) 
 Multiply the assumed radius by the number 3.1416, and increase 
 the product by the distance between the centres of the pulleys. 
 (2) If the quantity obtained by (1) is greater than half the length 
 of the belt, the assumed radius is greater than the one to be de- 
 termined. (3) If the quantity obtained by (1) is less than half 
 the length of the belt, the assumed radius is less than the one to 
 be determined. II. When the assumed radius is the greater of the 
 two, to find the other one. The distance between centres and the 
 length of belt are supposed to be given. (1) Multiply the as 
 sumed radius by the number 6.2832, subtract this product from 
 the length of the belt, and divide the remainder by the distance 
 between centres. (2) Add the quantity obtained by (1) to the 
 number 0.4674, and extract the square root of the sum. (3) 
 Subtract the quantity oljtained by (2) from the number 1.5708, and 
 multiply the difference by the distance between centres. (4) 
 Subtract the quantity obtained by (3) from the assumed radius ; 
 the remainder will be the required radius. III. Wlien the assumed 
 radius is the smaller of the two, to find the other one. (1) Same as 
 (1) of preceding rule. (2) Same as (2) of preceding rule. (3) 
 Subtract the number 1.5708 from the quantity obtained by (2), and 
 multiply the difference by the distance between centres. (4) Add 
 the quantity obtained by (3) to the assumed radius ; the sum v?ill 
 be the required radius. 
 
 E.mmple. — The first driving-pulley of a stepped cone has a ra- 
 dius of 12 inches, and the radius of the corresponding driven 
 pulley is 4 inches ; the distance between centres of pulleys is 3 
 feet, and there are three other pulleys on the driving-cone, having 
 radii of 9, 6, and 3 inches respectively. It is required to find the 
 radii of the corresponding pulleys on the driven cone. It will be 
 necessary first to calculate the length of belt required, which is 
 10.334 feet, or about 10 feet 4 inches. 
 
 Next find whether the pulleys on the driving or driven cone are 
 the largest. Half the length of belt is 5.167 feet. For the 9- 
 inch pulley, 0.75 multiplied by 3.1416 is 2.356, and adding 3, the 
 sum is 5.356, wliich is greater than 5.167, showing that the 9-inch 
 pulley is larger than the pulley to be determined. For the 6-inch 
 pulley: 0.5 multiplied by 3.1416 equals 1.571, and increased by 3 
 equals 4.571, and as this is less than 5.167, the 6-inch pulley is 
 smaller than the pulley to be determined. Of course, then, the 
 remaining 3-inch pulley is still smaller than the corresponding 
 pulley in the driven cone. 
 
 To find the radius of the pulley corresponding to the one on 
 the driving-cone whose radius is 9 inches : (1) 0.75 multiplied by 
 6.2832, 4.712. Subtracting 4.712 from 10.334, the remainder is 
 5.622 ; 5.622 divided bv 3, 1.874. (2) 0.467 added to 1.874, 2.341. 
 Square root of 2.341, 1.53. (3) Subtracting 1.53 fnmi 1.571, the 
 remainder is 0.041 ; 0.041 multiplied by 3, 0.123. (4) Subtract- 
 ing 0.123 from 0.75, the remainder is 0.627 feet, or about 7^ 
 inches, radius of required jjulley. 
 
132 ENGINEERING. 
 
 Pulley corresponding to driving-pulley whose radius is 6 
 inches : 0.5 multiplied by 6.2833 equals 3.142. This subtracted 
 from 10.334 equals 7.192, which divided by 3 equals 2.397— (1). 
 Adding 0.467, we have 2.864, the square root of which is 1.692 
 — (2). 1.692 diminished by 1.571 equals 0.121, which multiplied 
 by 3 equals 0.363 — (3). Adding 0.5 gives 0.863 feet, or about 
 lO^Y inches, required radius. 
 
 Pulley corresponding to driving-pulley whose radius is 3 
 inches : 0.25 multiplied by 6.2832 equals 1.571. This, subtracted 
 from 10.334, equals 8.763. Dividing the last by 3 gives 2.921— 
 (1) ; and by adding 0.467 we have 3.388. Of this the square root 
 is 1.841 — (2). Subtracting 1.571 givesO.27, which multiplied by 3 
 equals 0.81, and adding 0.25 gives 1.06 feet, or about 12^ inches, 
 required radius. 
 
 The radii of the several pulleys on the two cones then will be : 
 
 Driving-cone 12, 9, 6, 3 inches. 
 
 Driven cone 4, 7^, 10^, 12r6 inches. 
 
 B. 
 
 Pulleys, Set-screws for. — These should be made of cast-steel 
 with hollow points ; the ends should then be beveled to an edge 
 surrounding the hole, and tempered to a dark straw. When set 
 up, these screws cut circular indentations on the shaft, and exert 
 an enormous force of resistance. 
 
 Pulleys, Working value of. — Pulleys covered with leather, 
 iron pulleys polished, and mahogany pulleys polished, rank for 
 working value as 36, 24, and 25 \nn- cent respectively, wood and 
 iron uncovered being almost identical. 
 
 Rawhide Boxes for machinery. — A ])ractical machinist says : 
 " I have run a piece of nuicliiu«-ry in rawhide boxes for fourteen 
 years without oil ; it is good yet, and runs at 4500 per minute. I 
 put it in while soft, and let it remain until dry." 
 
 SiiAFTiNfi Accidents, Preventing. — Accidents are common in 
 large nuiniifactorics tlirougli tlu; cngagcnient of some jjortion of 
 a workman's garments witli a swiftly rotating shaft. A .siyi])le 
 way of rendering these casualties inqiossibh; is to cover the shaft 
 with a loose sleeve along its whole length. 'I'he sleeve may be 
 of tin or zinc, and made so as to be removable if -desired. The 
 friction between it and the shaft would be sufficient to cause its 
 rotation with tlie latter, biit of course, in event of a fabric be- 
 coming wrapped around it, it would <|uick!y stop, and allow of 
 the easy extrication of the same. 'J'he sleeve should be lined 
 with leather both witliiu and at the ends in order to ])revent 
 noise. Thcs same idea in the sluipe of loose covers miglit readily 
 be applied to cog-wlu^els or pulleys. 
 
 SiiAKTiN(!, Lining. — Evc^y out! operating long lines of shaft- 
 ing should provide an adjusting roil, as shown in the (engraving. 
 A may be a rod or a pier*; of gus])ipe, of suflicient length to 
 nrach from llie simft, (), to within about 4 feet of the floor ; an 
 ofTsca i)i(;ce, M, is fixed to the. top of this rod, which earries a 
 riglit and ]»;ft iiand screw, C ; two jaws, D, travel u|i<in this 
 BCrow, one upon tlm right and the otlier uixin the ht'l hand 
 
ENGINEERING. 
 
 133 
 
 thread, as shown. The screw may be worked by a ;J:-in. wire, E, 
 with a crank, F, at its lower end ; if a gas-pipe is used, the wire 
 may pass through the pipe, and the lower 
 end of the screw, C, enter the top of the 
 pipe as a bearing. If the rod, A, is of wood, 
 three or four wire staples will suffice as 
 guides for the wire, as indicated. A tar- 
 get, Q, with a clamp-screw, slides upon 
 the rod, for the purpose of easy adjustment 
 to the sights of the leveling instrument. 
 
 Now it will of course be apparent to 
 every one that, whenever several sizes of 
 shafting occur in the same line, this ad 
 justing- rod will always give the exact 
 central distance, O, of the shaft from the 
 target ; hence we have only to plant the 
 leveling instrument in a position to com- 
 mand a view of the target when suspend- 
 ed from each of the several bearings of a 
 line of shafting, in order to adjust the lev- 
 el of a line with the utmost expedition 
 and accuracy. An engineer's tripod and 
 level is, of course, the best instrument for 
 this pui'pose, but, when this is not at 
 hand, an ordinary builder's level may be 
 used : the longer it is, the better. Fix a 
 temporary sight at one end of the level ; a 
 piece of tin (with a small pin-hole) next 
 the eye, and a piece of tin or thin wood 
 with a large hole at the farther end, with 
 a vertical and a horizontal thread stretch- 
 ed across the hole, with their point of 
 intersection the same distance above the 
 level as the hole in the eye-piece. The 
 level may be used upon a level stand or 
 table, some five feet from the floor. 
 
 To adjust a line of shafting laterally, 
 an adjusting-rod must of course be used 
 horizontally in connection with a strong 
 line, stretched as taut as possible, at such 
 distance from the shafting as to need 
 nearly the full length of the rod to reach 
 it. The reason for placing the line at 
 such a distance from the shaft is to pre- 
 vent the difference in level between the 
 line and the shaft from materially impair- 
 ing the truth of the result. If the line is 
 very long, it will sag so much that a 
 plumb-line suspended from the measuring 
 
 point of the target or rod may be neces- „g,,j^.p^ ^^^^ ^^^^^^ 
 sary for perfect accuracy. shafting. 
 
 The jaws, D, should be so formed that 
 they may be applied to the inside of boxes. Pivot-boxes are 
 
134 ENGINEERING. 
 
 now so generally used, however, that this application of the rod 
 is not so common. 
 
 Shafts, Sprung:. — If a shaft sprintrg in running, the trouble 
 lies probably in either a too small diameter of the shaft for its 
 weijrht and velocity, a set of unbalanced pulleys, or an unequal 
 strain on either side by the belts. 
 
 Wood, Lubricant for. — A mixture of black-lead and soap. 
 
PEACTIOAL TECHNOLOGY. 
 
 CEMENTS, GLUES, AND MOULDING COMPO- 
 SITIONS. 
 
 Casts, To prepare plaster of Paris for.— Immerse tlie unburnt ' 
 gypsum for 15 minutes in water containing 8 or 10 per cent of 
 sulphuric acid, and then calcine it. Prepared in this way it sets 
 slowly, but makes excellent casts, which are perfectly white 
 instead of the usual grayish tint. 
 
 Casts, Transparent. — Beautiful semi-transparent casts of fancy 
 articles may be taken in a compound of 2 parts unbaked gyp- 
 sum, 1 part bleached beeswax, and 1 part paraffine. This be- 
 comes plastic at 130°, and is quite tough. 
 
 Cements. — Aii' and imter-tight, for casks and cisterns : Melt- 
 ed glue 8 parts, linseed-oil 4; boil into a varnish with litharge. 
 This hardens in 48 hours. Plumbers' : Black resin 1 part, brick- 
 dust 2. Melt together. For leaky boilers : Powdered litharge 2 
 parts, fine sand 2, slaked lime 1. Mix with boiled linseed-oil. 
 Apply quickly. Acid-proof : A paste of powdered glass and 
 concentrated solution of water-glass. Cutlers' : (1) Pitch 4 parts, 
 resin 4, tallow2, and brick-dust 2. (2) Eesin 4, beeswax 1, brick- 
 dust 1. (3) Resin 16, hot whiting 1, wax 1. This is used for fas- 
 tening blades in handles. For ivory or tnother-of -pearl : Isinglass 
 1 part, white glue 2, dissolved in 30 parts hot water and evaporated 
 to 6 parts. Add gum-mastic ^ part, dissolved in \ part alcohol, 
 and add 1 part zinc- white. Shake up and use warm. Jeiceler's, for 
 ■uniting all substances : Gum -mastic 5 or 6 bits as large as a pea dis- 
 solved in spirits of wine sufficient to render all liquid. In another 
 vessel dissolve the same amount of isinglass in rum enough to 
 make 2 ozs. of strong glue, adding 2 small pieces of gum ammo- 
 niacum, which must be moved until dissolved. Heat and mix 
 the whole. Keep in a closely-corked phial, and put the latter in 
 boiling water before using. Black, for bottle-corks : Pitch hard- 
 ened by the addition of brick-dust and resin. For jet : Use shel- 
 lac, warming the edges before applying, and smoke the joint to 
 make it black. For meerschaum or china : (1) Make a dough of 
 garlic, rub on the edges and bind tightly together. Boil the 
 object for half an hour in milk. (2) Use quicklime mixed to a 
 thick cream with white of egg. Soft, for steam-boilers : Red or 
 white lead in oil 4 parts, iron borings 3 parts. Oasfitters' : Resin 
 4^ parts, wax 1, Venetian red 3. Chopper smiths' : Boiled linseed- 
 oil and red lead made into a putty. This is used to secure joints 
 and on washers. For emery on to icood : E(]ual parts of shellac, 
 white resin, and carbolic acid in crystals. Add the acid after the 
 
136 rRACTICAL TECHNOLOGY. 
 
 others are melted. Iron and emery : Coat the meta. with oil 
 and white-lead, and when hard apply the emery mixed with fjlue. 
 Firnch ]mtfy,hni'd and permanent: Linseed-oil 7 parts, brown 
 umber 4, boiled for 2 hours, ^ part white-wax stirred in. Re- 
 move from fire and thoroughly mix in white-lead 11, and fine 
 chalk 5^ parts. India-rubher : Fill a bottle -^q full of native 
 india-rubber cut into fine shreds. Pour in benzole from coal-tar 
 till the bottle is f full. The rubber will swell ; and if the whole 
 be shaken every few days, the mixture will become as thick as 
 honey. If too thick, add benzole ; if thin, add rubber. This 
 dries in a few minutes, and will unite backs of books, straps, 
 etc., very firmly. C7iinese, for fancy articles, wood, yhtsfi, etc. : 
 Finest pale-orange shellac, broken small, 4 parts, rectified spirit 
 . 3 parts. Keep in a corked bottle in a warm place until dissolved. 
 It should be as thick as molasses. liust joints : (1) Clean iron 
 borings 2 parts, flowers of sulphur jV. sal-ammoniac -j^-. (2) 
 Finely-powdered iron borings 1 part, sal-ammoniac ^, flowers of 
 sulphur T^;. Pound together and keep dry. For use, mix 1 part 
 with 20 of pounded iron borinors, and mix to a mortar consis- 
 tence with water. F'or making metallic joints soinul : (1) Use 
 a i)utty of boiled linseed-oil and red-lead. (2) Use &, 
 putty of equal parts of white and red lead. For electrical and 
 chemical appartdtis : Resin 5 parts, wax 1, red ochre 1, plaster of 
 Paris \. Melt at moderate heat. For mending stone, or as mas- 
 tic for brick walls : Make a paste of linseed-oil with clean river 
 sand 20 parts, litluir<re 2, quicklime 1. For chucking work in the 
 lathe : (1) Black resin 8 parts, yellow wax 1 ; melt togetlier. For 
 use, cover the chuck to Vg in. thick, spreadinjr over the surface in 
 small pieces, mixing it with -jlr its bulk of gutta-percha in thin 
 slices. Heat an iron to dull red and hold it over the chuck till 
 the mixture and gutta-])crcha are melted and rKpiid. Stir the 
 cement with the iron until it is smoothly mixed. Chuck the 
 work, lay on a weight to enforce contact, and let it rest for half 
 an hour before using. (2) Burgundy pitch 2 ))arts, resin 2, yellow 
 wax i, dried wax 2. Melt and mix. (3) Resin 4 parts, nudted 
 with pitch 1. While boiling add brick-dust until dro])])ing a 
 little on stone shows the mixtures to be sufficiently liard. /'J/astic, 
 for leather or india-rubber : Hisuljjhidr of carbon 4 ozs., shrcd- 
 d(^d india-rubber 1 oz., isinglass 2 drachms, gutta-pt'rcha ^ oz. 
 Dissolve, coat the jjarts, dry, tlien heat the layer to melting, 
 place and press the parts together. Water-tight, for iroodcn vessels : 
 Lime, clay, and oxidt^ of iron, mixed, kfpt in a close vessel and 
 conqinundcd with water fur use. Fi>r huther, Htrojis, etc. : (Jut- 
 ta-pcrcha dissolved in bi.siiiphidi; of carl)on. Kec]) tightly cork«'d 
 and cool. It sliouid be of tlie consistenct'of molasses. For mar- 
 ble, or for attaching glass to metal: Plasler of Paris soakinl in 
 a Hafiirated solution of alum and baked hard, (iiiud to powdi-r 
 and mix witii wat(U' for use. Can be colonul to imitate! any 
 marble, and takes a fine p<»Iish. hnp(rri<nis, J'or corks, etc. : 
 Zinc-whit(! rubbed up willi co|)al varnish. (Jiv») two coats so as 
 to fill all tlie ]inri's, and liuisli with varnish alone. For cracks in 
 wood: (1) Slak<;d lime 1 part, rye meal 2, and linseed-oil 2. (2) 
 Use a paste of sawdust and ]>re|)are(l chalk with glue 1 ])art, 
 dissolved in water 10. {'<)) Uil-vainish thickened with equal 
 
PKACTICAL TECHNOLOGY. 137 
 
 parts of litharge, clialk, and white and red lead. For wood and 
 glass or metals : (1) Resin and calcined plaster, the former melted, 
 made into a paste. Add boiled oil to consistence of honey. (2) 
 Dissolved glue and wood-ashes to consistence of varnish. Fire- 
 proof and irater -proof : Pulverized zinc- white, sifted peroxide 
 of manganese, equal parts. Make into a paste with soluble 
 glass. To mend iron pots and pans : Partially melt 2 parts sul- 
 phur, and add 1 part fine black-lead. Mix well, pour on stone, 
 cool, and break in pieces. Use like solder with an iron. London 
 cement, for glass, wood, china, etc.: Boil a piece of cheese three 
 times in water, each time allowing the water to evaporate. Mix 
 the paste left with quicklime. For aquaria : (1) For fresh water 
 aquaria : Take \ gill gold-size, 2 gills red-lead, 1^ gills litharge, 
 and sufficient silver sand for a thick paste. This sets in about 2 
 days. (2). For fresh or salt water : Take ^ gill powdered resin, 
 1 gill dry white sand, 1 gill litharge, 1 gill plaster of Paris. 
 Sift ; and for use mix with boiled linseed-oil to which a little 
 dryer has been added. Mix 15 hours before using, and allow 2 or 
 3 hours to dry. For petroleum lamps, impervious to the oil : Re- 
 sin 3 parts, boiled with water 5 and caustic soda 1. Then mix 
 with half its weight of plaster of Paris. This sets in f hour. 
 Roman : Green copperas 3^ lbs., slaked lime 1 bushel, fine gravel 
 sand 1 bushel. Dissolve the copperas in hot water, and mix all 
 to proper consistence. Keep stirred. Glass to glass, for sign- 
 letters, etc. : Melt in a water-bath liquefied glue 5 parts, copal 
 varnish 15, drying-oil 5, oil of turpentine 2, turpentine 3. Add 
 slaked lime 10. Hydraulic : Oxide of iron 1 part, powdered 
 clay 3, and boiled oil to a stiff paste. Stone : Sand 20 parts, 
 litharge 2, quicklime 1, mixed with linseed-oil. Leather and 
 cloth, for uniting parts of boots and shoes, seams, etc. : Gutta- 
 percha 16 parts, india-rubber 4, pitch 2, shellac 1, oil 2. Mix and 
 use hot. Mahogany : Shellac melted and colored. Colorless, for 
 paper : Add cold water to rice-flour, mix, bring to proper con- 
 sistence with boiling water, and boil one minute. Water-proof, 
 for cistern stones : (i) Whiting 100 parts, resin 68, sulphur 18+^ 
 tar 9. Melt together. (2) Sand 100 parts, quicklime 28, bone 
 ashes 14, mixed with water. Transimrent : India-rubber 75 
 parts, chloroform 60. Mix, and add mastic 15. Cloth to iron : 
 Soak the cloth in a dilute solution of galls, squeezing out the 
 superfluous moisture, and applying the cloth, still damp, to the 
 surface of the iron, which has been previously heated and coated 
 with strong glue. The cloth should be kept firmly pressed upon 
 the iron until the glue has dried. For cracks in stoves: Finely- 
 pulverized iron (procured at a druggist's) made into a thick paste 
 with water-glass. The hotter the fire, the more the cement 
 melts and combines, and the more completely does the crack be- 
 come closed. For china, glass, etc. : Diamond cement, for glass 
 or china, is nothing more than isinglass boiled in water to the 
 consistence of cream, with a small portion of rectified spirit 
 added. It must be warmed when used. 2. White-lead rubbed 
 up with oil. Articles mended with this must stand for a month. 
 For corks of benzine-bottles : A paste of concentrated glycerine 
 (commonest kind) and litharge. This soon hardens, and is'insolu- 
 ble in benzine or any of the light hydro-carbon oils. For eaustie 
 
138 PKACTICAL TECHNOLOGY. 
 
 lye tanks • The tanks may be formed of plates of heavy-spar, 
 the joints being cemented together by a mixture of 1 part finely 
 divided india-rubber dissolved in 2 parts turpentine oil, with 4 
 parts powdered heavy-spar added. Colored : Soluble glass of 33** 
 B. is to be thoroughly stirred and mixed with fine chalk and the 
 coloring matter well incorporated. In the course of six or eight 
 hours a hard cement will set. The following are the coloring 
 materials : 1. Black : Well-sifted sulphide of antimony. This 
 can be polished with agate to a metallic lustre. 2. Gray-black : 
 Fine iron-dust. 3. Gray : Zinc-dust. This has a brilliant lus 
 tre, and may be used for mending zinc castings. 4. Bright green : 
 Carbonate of copper. 5. Dark green : Sescjuioxide of chromium. 
 6. Blue: Thenard's blue. 7. Yellow: Cadmium. 8. Bright red : 
 Cinnabar. 9. Violet red : Carmine. 10. Pure white : Fine 
 chalk as above. 
 
 Cement, Portland, To test. — Three tests are used : (1) Resist- 
 ance to tensile force. (2) Specific gravity. (3) Water test. The 
 first is by making a specimen briquette in a mould with a trans- 
 verse section of 2.25 square inches, the specimen being held ver- 
 tically in clips, which is placed under the .-^hort arm of a steel- 
 balance, and broken. A test of 500 lbs. has been used on an area 
 of 2.25 square inches after 7 days' immersion in water. The sec- 
 ond method is by finding the weight in ])ounds of the struck 
 bushel. The water test is useful when the others can not be ap- 
 plied. It consists of gauging a small quantity of the dry powder 
 with water, and immediately immersing it in water. If the 
 shari)er edges crack or break away after a short time, the cement 
 is too hot or fresh, or is inferior in quality. The weight of good 
 Portland fement ranges from 100 lbs. to 130 lbs. per bushel, equal 
 to from 80 lbs. to 102 lbs. per cubic foot. The lighter kinds set 
 more rapidly than the heavier, but are weaker. The specific gra- 
 vity should be of 110 lbs. to a bushel. 
 
 Glued Joints, Strength of. — Tlu; absolute strength of a well- 
 glued joint is given as follows in pounds per square inch : 
 
 
 Across the grain. 
 
 With the grain 
 
 Beech, 
 
 2133 
 
 1095 
 
 Elm, 
 
 1436 
 
 1134 
 
 Oak, 
 
 1735 
 
 568 
 
 Whitewood, 
 
 1493 
 
 841 
 
 Maple, 
 
 1422 
 
 896 
 
 It is customary to use from ^ to -^ of the above values to cal- 
 culate the resistances wliich surfaces joined with glu(* can perma- 
 nently be submitted to with safely. 
 
 CJlue, Fire-i)n)of. — A handful of <iuicklime mixed in 4 ozs. of 
 linseed-oil and boiled to a good thickness Tuakes, wiien spread on 
 plates and hardened, a glue which can be used in the ordinary 
 way, but wliidi will resist (ire. 
 
 Glue, Li<iui(i. — Dissolve the glue in an e(|uai amount of strong 
 hot vinegar, adding \ alcohol and a little alum. Will keep in- 
 definitely. 
 
 Glueh, Marine. — (1) Pure india-rubber 1 pt., dissolved by heat 
 
PRACTICAL TECHNOLOGY. ^39 
 
 in naphtha ; when melted, iidd shellac, 2 pts. (2) Glue, 13 pts., 
 water to dissolve, and yellow resin, 3 pts. Melt, add turpentine,' 
 4 pts., and mix. Portable, for draughtsmen : Glue 5 ozs., sugar 
 2 ozs., water 8 ozs. Melt in water-bath, cast in moulds, and dis- 
 solve for use in warm water. Fur bank-notes : Fine glue or 
 gelatine, 1 lb., dissolved in water, and the water evaporated until 
 nearly expelled. Add I lb. brown sugar, and pour in moulds. For 
 gutta-percha: Common black pitch 2 pts., guttapercha 1 pt. 
 Mould into shape. Elastic : Dissolve glue in a water-bath, evapo- 
 rate to a thick tiuid, and add an equal weight of glycerine. Cool 
 on a slab. Liquid : (1) White glue 16 ozs , dry white-lead 4 
 ozs., soft water 2 pints, alcohol 4 ozs. Stir and bottle while hot. 
 (2) Glue 3 pts. softened in 8 parts water. Add i pt. muriatic acid 
 and I pt. sulphate of zinc. Heat to 176° Fahr.''for 12 hours. Al- 
 low the compound to sei tie. Beat and moisture-proof; Linseed- 
 oil 4 ozs., 1 handful of quicklime ; boil to good thickness, and 
 cool. It will become very hard, but is as easily dissolved as com- 
 . mon glue. Water-proof, simple : Common glue 1 lb. boiled in 
 2 qts. skimmed milk. 
 
 Glue, Test for goodness of. — Assuming that that is the best 
 glue which will take up most water, take 50 grains of the speci- 
 men and dissolve it in 3 ozs. water in a water-bath. When dis- 
 solved, set it by for 12 hours to gelatinize, and tlien take an 
 ounce chip-box, place it on the surface of the gelatine, and put 
 shot into the box until it sinks down to a nuirk on the outside. It 
 will be found that the stronger the glu--, the more shot it will 
 take to sink the box down so that tlie mark sliall be level with 
 the surface of the gelatine. In a trial with very fine glue, 50 
 grains of glue dissolved and gelatinized with 3 ozs. of water, 
 supported to the mark on the box 6 ozs. of shot, at a temperature 
 of 58" Fahr. On trying the same experiment with best Kussian 
 isinglass, 9 ozs. of shot were supported, the temperature being 
 the same. This test is of course intended as a comparative one 
 between two kinds of glue, or between any kind taken as a stand- 
 ard and another compared with it. The "placing of the mark is 
 arbitrary. 
 
 Gluk, To bleach. — Soak in moderately strong acetic acid for 
 two days, drain, place on a sieve, and wash well with cold water. 
 Dry on a warm plate. 
 
 Moulding Architectural Ornaments. — A good composition 
 for this purpose is made of chalk, glue, and paper-paste. 
 
 Moulding Composition.— Five parts of sifted whiting mixed 
 with a solution of 1 part glue, together with a little Venice turpen- 
 tine to obviate the brittleness, makes a good plastic material, which 
 may be kneaded into figures or any desired shape. It should be 
 kept warm while being worked. It becomes as hard as stone 
 when dry. 
 
 Paste, To mould figures in. — Take the crumb of a new-drawn 
 white loaf, mould in a mass until the whole becomes as close as 
 wax and very i)liab]e. Then heat and roll with a rolling-pin. 
 Mould it to the required shape, and dry in a stove. 
 
140 PRACTICAL TECHNOLOGY. 
 
 PhotoCtRAPHIC Prints, To varnish. — Heat a piece of glass, and 
 rub a little wax over it with a bit of cottou-wool. Pour water 
 over the plate, and press the picture down upon it with a piece 
 of filtering-paper. When dry, the picture is removed, and ■will 
 be found to possess a brilliant surface. 
 
 Picture-Frames, Composition for. — (1.) To make composi- 
 tion ornaments for picture- frames : Boil 7 lbs. best glue in 3| 
 pints water, melt 8 lbs. Avhite resin in 3 pints raw linseed-oil ; 
 when the ingredients are well boiled, put them into a large ves 
 sel and simmer them for half an hour, stirring the mixture and 
 taking care that it does not boil over. When this is done, pour 
 the mixture into a large quantity of wliitlng, previously rolled 
 and sifted very fine, mix it to the consistence of dough, and it is 
 ready for use. (2) Dissolve 1 lb. glue in 1 gallon water ; in another 
 kettle boil together 2 lbs. resin, 1 gill Venice turpentine, and 1 ])int 
 linseed-oil ; mix together in one kettle, and continue to boil and 
 stir them together till the water has evaporated from the other in- 
 gredients ; then add finely-pulverized whiting till the mass is 
 brought to the consistence of soft putty. This composition will 
 be hard wlien cold ; but being warmed, it maj' be uioulded to any 
 shape by carved stam]>s or jnints, and the moulded figures will 
 soon become dry and hard, and will retain their shape and form 
 permanently. Frames of either material are well suited for gild- 
 ing. 
 
 Plaster Casts, To toughen. — Immerse in a hot solution of 
 glue long'enough for the mass to be well saturated. They will 
 bear a nail driven in witliout cracking. 
 
 Plaster Models, Mending. — Sandarac varnish is the best ma- 
 terial. Saturate the broken surfaces thoroughly, press them well 
 together, and allow them to dry. 
 
 Plaster Moulds. — Glycerine is said to be a good coating for 
 the interior, but ])ractical plaster moulders still use, as of old, a 
 mixture of lard and oil. 
 
 METAL- WC)RKING HINTS A^)KE('irES. 
 
 Ai.iiOV for filling defects in small castings. — Lead !) parts, 
 antiniuny 2, bi.-^nnith 1. Tliis expiinds on cooling. 
 
 Alloy ok Cori'Elt, which will attach itsilf to glass, metal, or 
 ]K>rcelaiii. — 20 to 30 parts finely ijleiidcd cnppi'r (made by n-duc- 
 lion of oxide of ro])per witli hydrogen or ))recipitation from solu- 
 tion of its suljjhate with ziiw) are made intn a paste with oil of 
 vitriol. To tills add 70 parts mercury ami triturate well ; then 
 wash out the acid with Itoiling waiter and allow llie conii)ound to 
 cool. In 10 or 12 hours, it Ijecoines sullicieiitly hard to receive a 
 brilliant indish and to scratch the surface of tin or gold. When 
 heated it becomes plastic, but does not cf)ntracton cooling. 
 
 Alloy, " Ohdikk." — This is made of pure copper 100 parts, tin 
 17 partH, mugnesia (i parts, Bal-aminoniac 3J parts, fpiicklinie 1^ 
 
PRACTICAL TECHJfOLOGY. 141 
 
 parts, tartar of commerce 9 parts. The copper is first melted, then 
 th ' magnesia, sal-ammoniac, lime, and tartar in powder are added 
 Litle by little and briskly stirred for half an hour. The tin is 
 lastly mixed in grains until all is fused. The crucible is covered, 
 and the fusion maintained for 3o minutes, when the dross is 
 skimmed oif and the alloy is ready for use. 
 
 Alloys, To extract silver from old. — Dissolve in nitric acid and 
 precipitate the chloride of silver with a solution of common salt. 
 The silver is reduced to a pure state by mixing the chloride with 
 an equal weight of bicarbonate of soda and sij^elting in a common 
 sand crucible. 
 
 ALLTbiiNUM Silver. — The following alloy is distinguished by 
 its beautiful color, and takes a high polish : Copper 70, nickel 
 23, aluminum 7, total 100. 
 
 Babbitt Metal. — There are a large number of recipes for this 
 alloy, but the following gives an excellent composition for gene- 
 ral use : Tin 50 parts, antimony 5 parts, copper 1 part. 
 
 Bell, Cracked, To repair. — A cracked bell which gives a jar- 
 ring sound may be improved by sawing or filing the ruptured 
 edges so that they are not brought together by the vibration of 
 the blow. 
 
 Boiler-tubes, Iron, To preserve. — A coating of red-lead and 
 boiled linseed-oil, applied to iron boiler-tubes, acts as a great 
 preservative. 
 
 Brass, Black stain for. — Arsenious acid 2 parts, hydrochloric 
 acid 4, sulphuric acid 1, water 80. 
 
 Brass Scrap, To utilize.— The best way is to melt it in with 
 new brass, putting it in with the zinc after the copper is melted. 
 
 Brass, To blacken. — ISIix 4 parts hydrochloric acid and 1 part 
 arsenic (by weight) ; put on bright, dry, and lacquer. 
 
 Brass, To clean. — Rub bichromate of potash fine, pour over 
 it about twice the bulk of sulphuric acid, and mix this with an 
 equal quantity of water. The dirtiest brass is cleaned by this 
 in a trice, ^^'ash the metal immediately after in plenty water ; 
 wipe, rub dry, and polish with powdered rottenstone. 
 
 Brass, Vert de Bronze on. To produce. — Dissolve 2 ozs. ni- 
 trate of iron and 2 ozs. hyposulphite of soda in 1 pint water. 
 Immerse the articles till they are of the required tint, as almost 
 any shade from brown to red can be obtained ; then wash well 
 with water, dry, and brush. One part perchloride of iron and 
 2 parts water mixed together, and the brass immersed in the 
 liquid, gives a pale or deep olive-green, according to the time of 
 immersion. If nitric acid is saturated with copper, and the brass 
 dipped in the liquid and then heated, the article assumes a dark- 
 green color. 
 
 Bronze for gongs and cymbals. — This is made with 20 per 
 cent of tin, and is hammered into shape while at a red heat ; it 
 is then tough and malleable, but is very brittle when cold. 
 
 Bronze for small castings. — Fuse together 95 part of copper 
 and 36 parts of tin. 
 
142 PRACTICAL TECHNOLOGY. 
 
 Bronze, Green. — Tlie bluish-green bronze used for ornamental 
 articles is made of any metal, first covered with a varnish made 
 of ground tin or bronze powder rubbed up with honey in gam- 
 water. Then wash with a mixture composed of sal-ammoniac 
 ^ oz., common salt ^ oz., and 1 oz. spirit of hartshorn in 1 pint 
 vinegar. After applying tlie mixture, leave for a day or two in 
 tne sun, and then, if necessary, add a second coat. This is a 
 good way to renovate old gas-fixtures. 
 
 Bronze, Japanese. — A curious bronze is produced in Japan, 
 which, when mad#in thin plates, resembles slate, and is covered 
 with designs in silver. It contains, in addition to copper, from 4 
 to 5 per cent of tin, and on an average 10 per cent of lead. The 
 combination is easily moulded into thin plates. Tiiese are var- 
 nished, and through the covering the designs are scratched with 
 a burin. The plate is then plunged in a silver-bath, when the 
 silver is deposited on the unprotected portions. Lastly, it is 
 placed in a muffle-furnace, when the copper blackens and the 
 silver remains bright. 
 
 Bronzing Hardware. — Brown bronze dip, for coating liat- 
 hooks and similar small hardwaie articles, is made of iron scales 
 1 lb., arsenic 1 oz., muriatic acid 1 lb., zinc, solid, 10 ozs. The 
 zinc should be kept in only when the bath is used. The castings 
 must be perfectly free from sand and grease. 
 
 Case-hardening, to be quickly performed, is done by the use 
 of prussiate of potash. This is powdered and spread upon the 
 surface of the iron to be hardened, after the iron is heated to a 
 bright red. It almost instantly fluxes and flows over the surface ; 
 and when the iron is cooled to a dull red, it is plunged in cold 
 water. Some prefer a mixture of ])russiatt' of potash 3 parts, 
 sal-ammoniac 1 part ; or prussiate 1 part, sal-amnnmiac 2 parts, 
 and iincly-powdered bone-dust (unburned) 2 parts. The appli- 
 catiim is the same in each case. Proper case-hardening, when a 
 deep coating of steel is desired, is done by ])acklng the article in 
 an iron box with horn, hoof, bone-ilust, shreds of leather or raw 
 liide, or either of these, and heating to a red lieat for from 1 to 
 3 hours, then plunging the box into water. 
 
 Chain, Strength of. — To ascertain the strength of short-linked 
 chains: (1) Multiply the scjuare of the diameter (reckoned in six- 
 teentlis of an incli) by .035 ; the ])roduct will be the weight the 
 chain will support in tons. ('^) The square of the diameter in 
 eighths of an inch = weight of chain in lbs. ])er fathom. The 
 s(|iiare of the diameter in eighths ■*■ 2 = breaking weight in tons. 
 Thus for a chain nnido of f iron, the weight = 3'' = 9 lbs. i)er 
 
 fathom, and its breaking weight would be -2-1 = A\ tons. The ut 
 
 most loud i)ut upon it should not exceed 1\ tons, the safe con- 
 stant load heing IH to 20 cwt. 
 
 Coloring .Mktai.s. — Take liyposulphito of soda 4 ozs., dis- 
 Bolved in 1\ jiiiits of watcir ; add a solution of 1 oz. acetate of 
 lead in sann! (piantity of water. Articles to be colon-dare placed 
 in th(! mixtur<', which is then gradually heated to boiling. Tin- 
 effect of the solution is to make iron ri-srinhle l)lu(^ steel; zinc 
 beconii'S brfuize, and cop|)er or brass beconii's successively y(;l- 
 lowish-red, scarlet, deep blue, bluish-white, and finally white 
 
PRACTICAL TECHNOLOGY. 143 
 
 with a tinge of rose. The solution has no effect on lead or tin. 
 By replacing the acetate of lead in the solution with sulphate of 
 copper, brass becomes of a fine rosy tint, then green, and finally 
 of an iridescent brown color. Zinc does not cover in this solution"; 
 but if boiled iu a solution containing both lead and copper, it be 
 comes covered with a black crust, which may be improved by a 
 thin coating ot wax. 
 
 Columns, Strength of hollow. — The hollow cylinder is the 
 strongest form of section under compressive force. The experi- 
 ments by which this was proved were conducted upon hollow 
 tapering columns of cast-iron, upon cross-sections, as used in the 
 connecting-rods of steam-engines, and upon forms in which the 
 metal was cast in the shape of the letter H. All these forms 
 proved considerably weaker than the hollow cylinder of equal 
 weight of metal. As the relative merits of these forms of cast- 
 ing metal are of constant use, we append their proportionate 
 strengths: Hollow cylindrical pillar, 100; H -shaped pillar, 75 ; 
 + -shaped pillar, 44. The examples w-ere all of the same weight 
 and length, with rounded ends. General Morin's rule for the 
 thickness of cast-iron pillars may be relied upon, as it is based 
 upon the founder's experience of the minimum thickness. 
 Height, feet, 7 to 10, 10 to 13, 13 to 20, 20 to 27.; minimum 
 thickness, inch, 0.5 0.6 0.8 1.0 
 
 Another rule is to make the thickness in no case less than ^ 
 of the diameter. Cellular or tubular girders exemplify to a still 
 greater degree the value of hollow construction. 
 
 Copper and Brass, Coating, with zinc. — Dip the articles into a 
 boiling concentrated solution of sal-ammoniac containing finely- 
 divided zinc. 
 
 Copper-welding. — A good welding mixture is composed of 
 phosphate of soda 358 parts, boracic acid 124 parts. 
 
 Crucibles. — The best crucibles are composed of the following 
 compositions, which are of two kinds — namely, with and without 
 plumbago. 3 parts by measure of the Stourbridge best crucible 
 clay, 2 parts cement, consisting of old used-up fire-bricks, and 1 
 part hard coke. These ingredients must be ground and sifted 
 through a ^ in. mesh sieve ; the sieve must not be finer, other- 
 wise the pot will crack. This composition must be mixed with 
 sufficient clean cold water, trodden with the bare foot to the con- 
 sistency of stiff dough and allowed to stand for 3 or 4 days, well 
 covered with damp cloths, to admit of its sweating and the parti- 
 cles of clay becoming thoroughly matured. It is then ready for 
 use, and must be blocked by hand on a machine. Owing to the 
 coarseness of this composition, the pot can not w^ell be thrown on 
 the potter's wheel ; and in no instance can it be made by press- 
 ing. The cruciljle must not be burnt in a kiln, but merely highly 
 and thoroughly dried before being placed iu the furnace for use. 
 For brass and copper melting, it will stand one good hard day's 
 work ; but care must be taken to replace the pot again in the 
 furnace after the metal has been poured. If the pot be not al- 
 lowed to go cold, it will last for several days. It will, with the 
 greatest safety, stand one melting of wrought-iron. The cost, 
 when made on the steel manufacturer's own premises, is about 
 
144 PRACTICAL TECHNOLOGY. 
 
 forty cents per pot, each pot holding from 100 to 120 pounds of 
 metal. Good Hessian crucibles are composed of 2 parts of the 
 best German crucible clay and 5 parts pure fine quartz sand. 
 Tliis composition must be sifted through a ^ in. mesh sieve ; it is 
 then tempered and trodden with the bare foot, as before de- 
 scribed. When ready for use, it is pressed into different sizes of 
 crucibles, which, when thoroughly dry, are placed in the kiln or 
 furnace and burnt hard. 
 
 Another cvrnpoKition : 2 parts best Stourbridge crucible clay, 
 3 parts cement ; sift through a i-iu. sieve ; temper as before de- 
 scribed and block by hand on the machine. When thoroughly 
 dry, it is placed in the kiln and burnt hard. These crucibles are 
 principally used for melting gold and silver, and also for dry 
 analysis. The best and most perfect fire-clay for crucible mak- 
 ing is nearly always found in the pavement of coal. Some of the 
 Pittsburg fire-clays, and those found to exist in the pavements 
 of some of the Pennsylvania coal-mines, are excellent fire-clays. 
 But the various compositions can not be described, as they are as 
 numerous as the different kinds of clay. The Birmingham soft 
 tough ])ot consists of 2 parts of the best Stourbridge crucible 
 clay, 3 jiarts plumbago, and 1 part cement, consisting of old used- 
 up crucibles ground and sifted through a \ in. mesh sieve. 
 
 Another componilion : 4 parts of the best Stourl)ridge crucible 
 clay, 3 parts plumbago, 2 parts hard coke, and 1 part cement, 
 consisting of old pots ground and sifted as before. Where old 
 pots can not be had, the above comi)osition must be burnt hard, 
 gn)und, and sifted. The scales or chippings of the insides of 
 gas-retorts are far superior to the best common hard coke. But 
 where scales and chipiiings can not bo had, hard coke is the best 
 substitute. All the ingredients of this composition must be sifted 
 through a \ in. sieve (but not finer), temi)ered, and made as be- 
 fore described. Wlicn thoroughly dry, it is placed in the kiln 
 and annealed, but not burnt hard. This composition makes a 
 pf)t (for melting the hardest metal) which can not be melted at 
 any ))itch of heat, nor can it be crjicked with the most sudden heat- 
 ing and cooling. It is regularly known to stand 14 and IG melt- 
 ings of iron — even wrought-iron. Any steel manufacturer can 
 make tlie pot on his own premises at a cost of !j;1.20 or there- 
 abouts, the pot holding from 100 to 120 lbs. of metal. 
 
 Etching upon Stkioi,. — \N'arm the steel, and rub on a coating 
 of white-wax or hard tallow. When hard, nnirk the device 
 through the wax with a shari)-point('d tool ; apply nitric acid, 
 and allow it to stand for a few minutes ; then wash off the acid 
 ihorouglily with water, heat the steel, and rub off the wax with a 
 rag. Tlie device will be found etched on the steel. 
 
 (ioi,D .\Ni) Stia'KU, Test for. — A good test for gold or silver is 
 a jiieci) of lunar caustic, fix(!d with a ])ointiMl stick of wood. 
 Slightly Wet the nu'tal to Ix- teste(l, and rub it gently with tin; 
 caustic. If gold r)r silver, the mark will be faint ; l)\it if an in- 
 ferior metal, it will be quite black. 
 
 Gi'N-Bakuiii.s, To bronze. — Clean thoroughly, and ai)ply (\^y 
 iiieans of a rag) nitric or sulphuric acid dilutecl with its volume 
 of water. 
 
PRACTICAL TECHNOLOGY. 145 
 
 Hardening Pickle. — Spring-water made into a brine strong 
 enough to float an egg, tiien boiled to precipitate the lime, and 
 allowed to cool. 
 
 Iron Articles, Brightening. — When taken from the forge or 
 rolls, the articles are placed in dilute sulphuric acid (1 to 20) for 
 an hour ; they are then washed clean in water, dried with saw- 
 dust, dipped for a second or so in nitrous acid, washed and dried 
 as before, and finally rubbed clean. 
 
 Iron Rings, Welding, without scaling. — Take iron filings 
 1000 parts, borax 500 parts, resinous oil of any kind 50 parts, 
 sal-ammoniac 75 parts. Pulverize completely and mix ; heat the 
 rings to a cherry red, powder the parts with the mixture, and 
 join them together. 
 
 Iron, Simple fire-plating for. — By rubbing the surface of iron 
 or other metals with soda amalgam, and then pouring over it a 
 concentrated solution of chloride of gold, the gold is taken up by 
 the amalgamated surface, and it is only necessary to drive off the 
 mercury with the heat of a large lamp to obtain a fine gilded sur- 
 face that will bear polishing. By writing or drawing a design 
 on the iron, the drawing will be re-produced in pure gold. Silver 
 and platinum salts are said to act in a similar manner to the 
 gold. 
 
 Iron, To gild cast. — The cheapest way is to use bronze or 
 mosaic gold. The castings are first to be heated hotter than the 
 hand can bear, but not so hot as to burn the varnish, and coated 
 with mosaic gold mixed with a small quantity of alcohol varnisli. 
 If the iron is polished, it must be heated previously and rubbed 
 over with a rag dipped in vinegar. 
 
 Lead, Determining presence of, in tiu vessels. — The metal to be 
 tested is first touched with nitric acid and then heated, when the 
 acid evaporates. If lead be contained, stannic acid and nitrate of 
 lead remain. Iodide of potassium is then applied, forming yel- 
 low iodide of lead ; while the stannic acid is white. The yellow 
 stain, therefore, indicates lead, the white, tin. . 
 
 Jewelry, To restore the lustre of. — Take 1 oz. cyanide potas- 
 sium and dissolve in 3 gills water. Attach the article to be 
 cleansed to a wire hook, immerse and shake in the solution for a 
 second or two, and remove and wash in clean water, then in warm 
 water and soap. Rinse again, dip in spirits of wine, and dry in 
 boxwood sawdust. If the solution is kept, put it in a tightly- 
 corked bottle, and label POISON conspicuously. One caution is 
 necessary : Do not bend over the solution so as to inhale the 
 odor, nor dip the fingers in it ; if one of the articles drops from 
 the hook, better empty the solution into another vessel. 
 
 Metal Surfaces, To protect, from moisture. — Inclose them 
 in tight compartments containing lumps of (luicklime. 
 
 Minerals and Metals, Hardness and tenacity of. — In mine- 
 ralogy, in which science the hardness is an important characte- 
 ristic, ten bodies are usually taken as points of comparison — the 
 softest being termed 1 and the hardest 10. These are : 1 , talc ; 
 2, gypsum ; 3, carbonate of lime ; 4, fluor-spar ; 5, phosphate of 
 lime ; 6, felspar ; 7, quartz ; 8, topaz ; 9, corundum ; 10, dia 
 
146 PRACTICAL TECHNOLOGY. 
 
 niond. Hence, when scientific works speak of the hardness of a 
 body being 6, 8, 4, etc., reference is made to the relative hard- 
 ness expressed by the list above given. 
 
 The tenacity of metals is estimated by the resistance which 
 wires of the same diameter experience when passed at etjual tem- 
 perature through the same hole of a draw-bench. The following 
 table gives the relative tenacity of various metals and alloys : 
 Steel already drawn, 100 ; iron already drawn, 88 ; brass already 
 drawn, 77 ; gold at 0.875, annealed, 73 ; steel annealed, 65 ; cop- 
 per already drawn, 68; silver at 0.750, annealed, 58; silver at 
 0.875, 54 ; brass annealed, 46 ; iron annealed, 43 ; platinum an- 
 nealed, 38 ; copper annealed, 38 ; fine gold annealed, 37 ; fine 
 silver annealed, 37 ; zinc, 34 ; tin, 11 ; lead, 4. 
 
 Plathstum-Bronze. — This is made of nickel 100 parts, tin 
 10, platinum 1. It is entirely unoxidizable, and especially 
 adapted for cooking-utensils. 
 
 Quicksilver, Coating iron with. — Clean the iron first with hy- 
 drochloric acid, then immerse it in a dilute solution of sulphate 
 of copper mixed with a little hydrochloric acid, by means of 
 which it becomes covered with a slightly-adherent layer of cop- 
 ])er. It is then to be brought into a very diluted solution of mer- 
 curial sublimate mixed with a few drops of hydrochloric acid. 
 The article will become covered with a layer of mercury, which 
 can not be removed even by rubl)ing. This is good as a protec- 
 tion from rust. 
 
 S.VDIKONS, Finishing. — See that your bufF-wlieels are well- 
 balanced after they an; covered. Let the wheel be covered with 
 tliicli leather before covering with emery. Get as good a surface 
 <m the article as you can from a wheel covered with No. 70 emery. 
 Mix flour of emery with melted beeswax, and stir in till it is 
 thick. When tlie mass is cool, rub it on a newly-covered wheel 
 with No. 80 emery. Then set tlu; wheel running, and hold on a 
 flint to smooth it until the surface is sutlici<'ntly fine to suit. 
 
 SiLVKU Orn.^ments, Imitation. — Ordinary i)laster models are 
 covered with a thin coat of mica powder, which perfectly re- 
 ])laces the ordinary metallic substances. The mica ])lates are 
 first cleaned an<l bleai-hed by tire, boiled in hydrochloric acid, and 
 waslicii iiiid dried. 'I'lic material is tlien finely jtowdered, sifted, 
 and mingled witii collodion, which serves as a vehich^ for ai)i)ly- 
 ing tin? com])ound witli a paint-brush. Tlie objects tlius jjrejjar- 
 ed can l)e waslied in water, and are not liable to bti injured by 
 snlphnrettcd a<ids or dust. Tlie collodion adheres perfectly to 
 glass, ])<jrcelain, wood, metal, ur pupii^r iiKirlii'. 
 
 Sii.VEH, Producing satin finish on, by sand-blast. — 'i'he follow- 
 ing isthemetiiod adopted at a large silver-idating establishment : 
 Air is coin])ressed by the driving engine of tlx^ works into an or- 
 dinary reservoir, ami tlience distril)utcd tlirongli pipes whicli ex- 
 tend along tlie tront of the workmen's tallies ; and alxivii tlie lat- 
 ter is a sand recejitacle, V-sliaped, from which a stream of sand 
 fallfl, and is met by a downward blast from the jilpe, which cur- 
 rent drives tbe material in a stream throngli a small hole in th(^ 
 table, beiieatli wliich ii rece|itacle to rec-eive tlie sand is ])laced. 
 'i lie workman, wlio.se fingers are covered with rubber to jirotect 
 
PRACTICAL TECHNOLOGY. 147 
 
 them, holds the article in tlie jet and under the table, watching 
 it through a pane of glass let into the top of the latter. The 
 operation is necessarily very rapid, as the article has only to be 
 turned so that the blast strikes the required portions, when the 
 work is completed. The exposure to the jet, even for an instant, 
 would cut through the Britannia, upon which the plating is 
 afterward deposited. By the interposition of rubber screens of 
 suitable shape, against which the sand has no abrading effect, any 
 fancy patterns or letters are easily imprinted on the surface, the 
 latter, of course, being satin-finished, while the spaces protected 
 by the screens are afterward burnished. 
 
 Silver, Restoring color to. — This is adapted to treating silver 
 filagree ornaments, rendering them dead white. The process has 
 long Ijeen a trade secret. If any pewter is found in the articles, 
 it should not be attempted. Pound together charcoal 3 parts, 
 and of nitre 1 ; add sufficient water to form a paste. With a 
 camel's-hair brush give the article a thin coat of the mixture, put 
 it in a small annealing-pan, and submit it to the fire until it be- 
 comes red-hot ; then withdraw it from the fire, let it stand a mi- 
 nute, and turn it out into a weak solution of sulphuric acid (1 part 
 acid, 10 parts water) in the boiling-pan. Boil, pour off the acid, 
 rinse ; wash with warm water and soap, using a soft brush ; dip 
 in spirits of wine, and dry in boxwood sawdust. If any spots 
 should srtll remain on the work, anneal it without the mixture, 
 boil out and wash as before. Burnish the parts intended to be 
 bright. Do not use the common American saltpetre. The Eng- 
 lish nitre, although it costs more, is really less expensive, as a 
 smaller quantity goes further and does the work more effectual- 
 ly. Purchase at the wholesale druggists. 
 
 Silver, To regain, from broken black-lead crucibles. — Pulve- 
 rize the crucible and digest it in ^nitric acid for several hours. 
 Decant off the clear liquid, and add to it muriatic acid until no 
 further precipitate forms. Allow to settle, and again decant the 
 clear liquid, wash the precipitate several times with clean water, 
 dry, and fuse in a small crucible with a quantity of carbonate of 
 soda. 
 
 Slag, Utilization of. Prussian method. — The high furnaces 
 are provided with a continual overflow for the slag, which runs 
 through a narrow gutter formed in the sand into a shallow pit, 
 through which a small stream of water is kept running. By this 
 chilling process the slag assumes the form of a fine gravel. An 
 endless chain at once lifts the slag out of the pit and loads it upon 
 cars. By grinding this material fine in a cement-mill, it is form- 
 ed into an excellent sharp building-saiid ; the great bulk of it, 
 however, is used, without further reducing its grain, for making 
 bricks. 
 
 For this purpose it is mixed with one half of its bulk of mor- 
 tar in a trough in which three shafts provided with long blades 
 are revolving. It is then shoveled into the brick-machines, each 
 of which turns out about twenty-five bricks a minute. These bricks 
 are piled up in tlie open air for drying, and are ready for use after 
 about six weeks. They continue to harden on exposure to the 
 air, and are said to possess greater strength than ordinary burnt 
 
148 PRACTICAL TECHNOLOGY. 
 
 bricks. They are extensively used for all kinds of buildings, 
 tlieir liglit-gray color producing a very pleasing effect, and the 
 roughness of their surface fitting them particularly well for re- 
 taining a coating of mortar. They can not be used, however, for 
 foundation walls, as by the absorption of moisture their cohesive- 
 ness is impaired. 
 
 The most interesting process is the following : As a thin stream 
 of the fluid slag, falling from a narrow gutter, passes the nozzle 
 of the steam-pipe, a jet of steam is blown through it, and by this 
 simple process it is solidified in the form of most delicate fibres, 
 resembling asbestos or spun glass ; and it falls to the ground like 
 a loose mass of grayish wool. This material is an excellent 
 non-conductor of heat, and is used for covering steam-pipes, boil- 
 ers, etc. The sole expenditure in its manufacture is that of the 
 steam, the exact amount of which could not be ascertained. 
 The material is sold for about $5 per cwt. The steam-pipe is 
 about 1^ inches in diameter, and the nozzle is simply a pipe, flat- 
 tened and then curved into a semicircular form, in order to give 
 the most advantageous shape to the steam-jet. The steam used 
 has a pressure of about 50 lbs. per square inch. 
 
 Soldering Liquid. — Into hydrochloric acid place as much 
 scrap-zinc as it will dissolve, still leaving a sponge of zinc. Use 
 the mixture for soldering brass-work. To solder cast or wrought 
 iron, add sal-ammoniac ; and for sheet-tin work, omit the sal-am- 
 moniac. 
 
 Solder, Jewelers'. — Melt 1 part lead, add 2 parts tin, and 
 throw in a small bit of resin as a flux. This is strong, easily 
 flowing, and white. In soldering flne work, w(»4 the parts to be 
 joined with muriatic acid in which as much zinc has been dissolv- 
 ed as the acid will take up. It is cleaner than the old method of 
 using Venice turpentine or resin. 
 
 Solder, Silver. — Put into a clean crucible, silver 2 parts, clean 
 brass 1 part, with a small ])iece of borax. Melt and pour into in- 
 gots. Solder made from coin, as it frecjuently is, often meets 
 with difficulty around the joints, requiring the use of the file to 
 remove! it, while the addition of any of the inferior metals to the 
 Bolder causes it to eat into the article joined by it. 
 
 Sthkl and Iron, To clean, from tcmponiry and sliglit rust. — 
 Cocoanut husks are better than wastes and turpentine. 
 
 Steel, Ciihome. — This metal is not only one third stronger 
 than any other steel, but can be produced at a small c^ist, from 
 the fact that when worn out, as in a steel-headed rail, it has a 
 market value, as it can be made over again, which is not Mie case 
 with Bessemer or any other cast-st<'cl. It will also weld without 
 borax or flux, and when burnt can be redeemed on the next heat. 
 
 Steel, PoLisirED, To bronze. — To 1 pint methylated spirits 
 add 4 ozs. gum shellac and k oz. gum-benzuin ; i)Ut the l)(>ttle in 
 a warm place, shaking it orcuHionaliy. When dissolved and set- 
 tled, decant tlie clear licjuid and keep it for line work. Strain tlie 
 residue tlirough a fine cloth. Take i lb. powdered bronze gre(>n, 
 varying to suit the taste with lanii)bla('k, red ochre, or yellow 
 ochre. Take as mucli varnish and bronze-ixiwder as required, 
 and lay it on the article, wliich must be tlioroughly clean and 
 
PRACTICAL TECHl^OLOGY. 149 
 
 slightly warm. Add another coat if necessary. Touch up with 
 gold-powder according to taste, and varnish over all. 
 
 Steel, Protecting, from rust. — ParafEne is the best material 
 for polished steel or iron. 
 
 Steel Rails, Cutting. — Remarkable results have been obtain- 
 ed with a disk made from a rail-saw and rotated at 3000 revolu- 
 tions per minute. As the disk was 9.6 feet in diameter, the velo- 
 city of its circumference was in the neighborhood of 86,400 feet 
 per minute. Steel rails were cut with astonishing rapidity, and 
 even melted. Millions of sparks were thrown off, but no heating 
 of the disk could be detected after the cutting. 
 
 Tin, Crystallization of. — A platinum capsule is covered with an 
 outer coating of parafRne or wax, leaving the bottom only unco- 
 vered. This capsule is set upon a plate of amalgamated zinc in 
 a porcelain capsule. The platinum is then filled completely full 
 of a dilute and not too acid solution of chloride of tin, while the 
 porcelain is filled with water acidulated with ^ of hydrochloric 
 acid, so that its surface comes in contact with the surface of the 
 liquid in the platinum. A feeble electric current is set up, which 
 reduces the salt of tin. The crystals formed after a few days are 
 well developed. They are washed with water and dried quickly. 
 
 Tin, Removing, from copper vessels. — Immerse the articles in 
 a solution of blue vitriol. 
 
 Tin, Removing, from plates without acid. — Boil the scrap-tin 
 with soda lye in presence of litharge. 
 
 Welding Powders for iron and steel. — (1) Iron filings 1000 
 parts, borax 500, balsam copaiva, or other resinous oil, 50, sal- 
 ammoniac 75. Mix together, heat, and pulverize. Weld at cher- 
 ry-red. (3) Borax 15 parts, sal-ammoniac 2, cyanide of potas- 
 sium 3. These constituents are dissolved in water, and the wa- 
 ter itself afterward evaporated at a low temperature. 
 
 Zinc, Black color for. — Clean the surface with sand and sul- 
 phuric acid, and immerse for an instant in a solution of sulphate 
 of nickel and ammonia 4 parts, in water 40 parts, acidulated with 
 sulphuric acid 1 part. Wash and dry. This takes a bronze 
 color on burnishing. 
 
 Zinc Labels, Ink for writing on. — (1) Verdigris 1 oz., sal-am- 
 moniac 1 oz., lampblack i oz. , water I pint ; mix well in a mor- 
 tar, and shake before using. Write with a quill. (3) One drachm 
 chloride of platinum dissolved in } pint water. 
 
 Zinc, Painting. — Use a mordant of chloride of copper 1 part, 
 nitrate of copper 1, sal-ammoniac 1, dissolved in water 64. Add 
 hydrochloric acid (comrnercial) 1. This brushed over the zinc 
 sheets gives them a deep black color, turning grayish after dry- 
 ing, in from 13 to 34 hours. A coat of oil-color will adhere to 
 this surface and withstand weather excellently. 
 
 Zinc-White, To restore. — This may be done by ignition in ai; 
 earthen crucible. 
 
150 
 
 PRACTICAL TECHNOLOGY. 
 
 SIMPLE IXSTRrMENTS AND THEIR USES. 
 
 Balance, Simple spring. — A is a deal stand 13 by 3 inches ; 
 B is a bard-wood block firmly attached to A ; C is a spring; 
 D is an index-pillar ; E is a scale-holder ; F is a small bent piu 
 to hold the spring steady while changing the scale-pan. The 
 
 >1M1'LK )1AI..\N<.E. 
 
 spring C should be very fine steel wire, bent over so as to form 
 a loop near the index for E to hook into. The index is a slip of 
 card sot out with a fine pen. The scale-pan is of thin letter- 
 paper, circular, and folded like a filter-paper, as indicated by tlie 
 dotted line. With this minute fractions of a grain can be re- 
 cognized. 
 
 B.VKO.METER, To make a cheap. — Obtain a straight fine glass 
 tube, about 33 inches long, and with as clean an interior as possi- 
 ble, sealed at one end, and having an even uniform bore of about 
 2j lines diameter. The mercury to be used irhould be perfectly 
 pure and free from all air and moisture. This latter requisite 
 may be assured by heating the mercury in a ])orcelain dish to 
 nearly tli*; boiling-i)oint, previous to using it. The tube is then 
 held securely, with the ojjen end up])ermost, and carefully filled 
 with the ru|uid metal. The open end of the tube is then securely 
 covered with the linger, the tube inverted, and the end covered 
 hy tht! finger ])luMge(l below the surface of a little mercury placed 
 in a small vessel to receive it. The finger is then removed, when 
 the nuircury in the tube will immediately fall to a h'vel of about 
 30 ini'hes above the surfac«^ of that in the small reservoir below. 
 In order to attach the scale correctly, it will he necessary to com- 
 pare the indications with those of some good instrument. 
 
 BAKOscorK, To make a. — Take any bottle ; pour colored wafer 
 into it, about ', of the (juantity the bottle will lK)ld ; insert in it a 
 glass tub<\ from 3 to 4 feet long, and passing air-tight through 
 the stop]>er, which must also Ix? airtight. Let a paper index, 
 divided according to any scale of division, say into inches and 
 fractions of uu incli, be glued to the glass lube, lilow inio the 
 
PRACTICAL TECHNOLOGY. 
 
 151 
 
 glass tube so as to cause the water to ascend tlie tube a few inches, 
 say 10 inches, and the instrument is constructed. The bottle 
 must be placed in another vessel, and protected by sawdust, or 
 some other material, from the influence of changes in the tempe- 
 rature of the atmosphere. This very sensitive instrument records 
 faithfully any change in the density of the external air, and the 
 approach of a storm will infallibly be indicated by a sudden rise 
 of the water in the glass tube. 
 
 Camera, Wonder, How to make a. — A wonder camera is a 
 sort of magic lantern, so contrived as to enable one to use opaque 
 objects for projection upon the screen instead of glass transparen- 
 cies. For example, if a photograher wishes to show his customer 
 how an enlargement from a carte will look, he simply has to put 
 the carte in the wonder camera, and " throw it up." Many en- 
 largement-scales may be made in this way. It consists of a 
 wooden box, with a top made of tin or sheet-iron ; the chimney 
 is made of the same material. The lens is the same as used upon 
 a camera for making photographs. At the back of the box (as 
 will be seen by reference to the elevation and plan, Figs. 2 and 3) 
 are two doors placed upon hinges. 
 
 When the box is in use, the door e is kept closed. The other 
 door consists of two parts placed at right angles to one another ; 
 
 Fig. 1. 
 
 Fig. 2. 
 
 A ■WO'TTDEB CAMERA. 
 
 the object of this is to fill the opening in the door e while the 
 pictures are being attached to c ; w^hen c is swung into position 
 opposite, the lens, placed at h d, is carried to one side. If stereo- 
 scopic views are to be shown, a slit may be cut at e, through 
 which they may be inserted with- 
 out opening the box. The door e 
 should be cut off a little at the 
 bottom, so as to admit air. The 
 light is placed at 7^ as nearly oppo- 
 site the picture as possible. It 
 should be a strong light ; an ar- 
 gand burner is the best. At the 
 back of the light is a piece of tin, 
 bent into the form of a reflector. Fig- 3. 
 
 The light coming from h strikes c, and is reflected through 
 the lens upon the screen. The plan of the box is represent- 
 ed with the top removed. No dimensions are given, as they 
 will depend upon the focal distance of the lens and height of 
 
152 PRACTICAL TECHNOLOGY. 
 
 the light. Care must be used to have the distance from the 
 lens to c when closed equal to the focal distance. 
 
 Electrical Machine, A simple. — A B, in the annexed en- 
 
 S 
 
 A SIMPLE ELECTRICAL MACHINE. 
 
 graving, is a glass tube fixed at one end in a wooden handle. 
 The rubber, with its flap, D, carries a little Leyden jar, the 
 end of which is visible at F. This jar is coated inside and 
 out with a resinous insulating compound, and the metallic lining 
 of the inside of the jar is in contact with the brass collecting- 
 ring, E. The handle being held in one hand and the rubber in 
 the other, when the tube is rubbed the little ring and jar rapidly- 
 collect electricity. A i inch spark and smart shock may be readily 
 obtiiined from this apparatus, the length of the spark depending 
 upon the amount of rubbing each time before the jar is dis- 
 charged. When it is not desired to take the shock through the 
 human body, the jar may be discliarged by means of the metallic 
 cord, H. 
 
 Electuical Orrery, to accompany the above machine. — This 
 is represented below. It is balanced on a pivot at F. The 
 
 ELECTRICAL ORRERY, 
 
 light hollow brass ball. A, represents the sun, and pith balls, B 
 and D, the earth and moon, rotating about the pivot E. The 
 metallic i)oints jn'ojecting troni H and 1) (in opposite directions, 
 of course) cause thfse to rotati- round each other ; but the lever- 
 age of the ])oint I) b(!ing, from its position, greater than the 
 leverage of B, it sets the long arm of the orrery in rotation uj)on 
 tlu' pivot F. 
 
 (J.m.vanometku, To make a 8imi)le. — Take an ordinary pocket- 
 coMipasB and wind 100 feet of No. 18 insulated copper wire 
 iiroimd it. 
 
 Kai.kidoscopk, To make a. — Take two strips of glass, 8 or 10 
 in. long, 1 to \\ in. l)road at one end and nbout \ as l)r<)ad at the 
 oth(!r. Hhu-ken one side; of each witli black varnish. Put two 
 HMiootli straight edges together, and form a hinge by gluing a 
 strip of clotli over tlir two edges. Make the angle between the 
 
PRACTICAL TECHNOLOGY. 153 
 
 Strips of glass an aliquot part of 180% as 20°, SO*', or 45°. Cover 
 the open side of the triangular prism with black velvet. Place 
 in a tin or pasteboard tube so that the angle of the smaller end of 
 prism is nearly in the centre. Cover top of tube with clear glass, 
 and cover this with paper, except a small hole in centre. In bot- 
 tom of tube, form a cell by placing two pieces of glass i in. apart 
 (the lower one of ground glass). In this cell place fragments of 
 broken colored glass, beads, etc. They must be capable of free 
 movement in the cell when the tube is turned in the hand. 
 
 Leyden Jar, To make a cheap.— Line a thin glass candy-jar 
 inside and outside with tin-foil, such as is used to wrap chew- 
 ing-tobacco in. Stick the foil, on with mucilage, varnish, or 
 flour paste. A still cheaper plan is simply to fill a glass jar nearly 
 full of water, and place it within another vessel of water, so that 
 the water, both outside and inside, shall be on the same level. 
 
 Magic-Lantern Slides, Painting. Four methods. — (1) Use 
 transparent colors, like Prussian blue, gamboge, and carmine. 
 These will give the three primary colors, and by their mixture, 
 the other tints. Apply witli a brush, and a transparent drying 
 varnish, like dammar varnish. Allow one coat to dry before ap- 
 plying a second. Considerable aid can be derived from stippling, 
 the color being strengthened, where necessary, by applying it 
 with the point of a fine brush. The colors must not be used too 
 thin. (2) Flow the glass plate with albumen, after the manner 
 of photographers, and paint with aniline colors. This process 
 gives great softness and brilliancy to the pictures, but they are 
 apt to fade. (;J) Paint with water-colors, and then flow the entire 
 surface with Canada balsam, covering the painted side with a 
 glass plate. (4) Use water- colors, but mix them with turpentine 
 instead of water, and work rapidly. 
 
 Meridian, To find the.— Mr. George W. Blunt says : _" Take a 
 piece of board, or any similar material, and describe on it a num- 
 ber of concentric circles. Place this in the sun ; over the centre 
 hang a plummet. Observe the shortest shadow from the plum- 
 met ; the sun will then be on the meridian ; draw a line to the 
 centre of the circle, and that will be the true meridian-line. This 
 will do to mark the apparent time, or to correct the compass for 
 variation." 
 
 Mirrors, Globe, To make. — Melt together 1 oz. clean lead and 
 1 oz. of fine tin in a clean iron ladle ; then immediately add 1 oz. 
 Insmuth. Skim off the dross, remove the ladle from the -fire, and 
 before it sets add 10 ozs. quicksilver ; now stir the whole care- 
 fully together, taking care not to breathe over it, as the fumes of 
 mercury are very pernicious. Pour this through an earthen pipe 
 into the glass globe, which turn repeatedly around. 
 
 Pipes, Determining proportions of. — The instrument consists 
 simply of a piece of wood shaped like a set- square, as shown in 
 Fig. 1, or a diagram of the same form drawn on paper, and di- 
 vided out along the two edges, which are at right angles to each 
 other, the divisions being taken to represent inches, feet, or yards, 
 etc., according to the kind of work for which the instrument is 
 used. Suppose that two pipes, A and B, Fig. 2, respectively 5 iu. 
 
154 
 
 PRACTICAL TECHNOLOGY. 
 
 and U in. in diameter, deliver into a third pipe, D, and it be re- 
 quired to find the proper diameter fortlie latter pipe. Then from 
 5 on the scale of one of the divided edges to 4^ on the other. 
 
 FIG.I 
 
 APPARATUS FOR DETERMINING THE DLAMETER OP PIPE8. 
 
 draw a line, as shown dotted in Fig. 1, and the length of this 
 line measured with tlif^ saiiu^ scale as that to which the edges are 
 divided, will be the diameter of pipe re(iuin'(l ; in this case, 6 J 
 in. On the other hand, if a pipe, D, GJ in. in diameter, be deliver- 
 ed into a pipe. A, 5 in. in diameter, and it was required to know 
 what other size of pipe, B, could also be 8up])lie(l, all that would bo 
 necessary woiilil l)e to take the division ])oiMt 5 on one edge as a 
 centre, and, with (Ji{ in. as a radius, describe an arc cutting the 
 other divided edge. The point at which tlm latter edg(( was cut 
 by this arc would show the diameter of ])ipe required. 
 
 Hifi-k-Tki,ks('OPK, To make a. — Object-glass should belialf an 
 in. in diameter, focus 24 in., or as long as convenient. Kye-])iece 
 may be a single lens of low ])()\ver with cross spider lines fixed in 
 its focus. The target will then appear invc^rted. The lenses are 
 inch)S(;d in a l>rass tube with a hiiigoor ball joint at the breech or 
 eye-piece end, and slides at tlie muzzle, to depress tln^ ol)ject glass 
 for increased elevation. 'i"he two ]>(iints of attachment to the bar- 
 rel are the same as for ordinary fore-and-leaf sights. 
 
 TELKHCorE, To make a cheap. — A correspondent says: " 1 ee- 
 
PRACTICAL TECHNOLOGY. 155 
 
 lected a meniscus 1 in. in diameter and of 48-iu. focus. This was 
 for my object-glass. I bad already in my possession a two-lensed 
 double-convex jeweler's eye-glass ; one of tbese lenses was used 
 for the eye-piece, its focal leugtb being a trifle over 1 in. The 
 tube was made of pine-wood. A piece of straight, evenly-grained 
 one-in. pine board, 2 in. wide and 8 feet long, was cut in the mid- 
 dle, and the two pieces, after making a tapering semicircular 
 groove in eacli, well glued together. This done, the next thing 
 was to give it a round, tapering form, 2 in. in diameter at one end, 
 and a trifle over an iucli at the other. This was done with a com- 
 mon carpenter's plane. I now had a tube 4 feet long, with a ta- 
 pering bole througb its length, and 1^ in. in diameter at its larg- 
 est end. Two wooden cells for the lenses were then turned in a 
 lathe, and were made to go on to tbe tube, as does the cover of a 
 wooden pill-box. A round bole, the size of the lens, was made 
 in each, the meniscus being contracted to f in., and the e_ye-glas3 
 to ^ in. diameter. The piece carrying the eye-glass Avas made so 
 as to slide some distance on the tube, for adjustment to distinct 
 vision. The tube was painted and varnished, and mounted equa- 
 torially ; and it proved to be a good instrument, showing Jupiter's 
 moons, their movements and eclipses, handsomely, the ring of 
 Saturn, the horned appearance of Venus, the mountains and cra- 
 ters on the moon, the spots on the sun, etc. Several of the nebu- 
 lae were also visible, especially those in Andromeda, Orion, Her- 
 cidea, and Sagittarins. The whole need not cost over two dollars, 
 beside the time in making, provided one is a mechanic. 
 
 " The meniscus (concave on one side and convex on the other) 
 is the proper form for a single-lens object-glass, and a plano-con- 
 vex lens makes the best form for the eye-piece. Care must be 
 taken to so set the lenses in their cells that their foci will meet 
 centrally. When this is the case, the lenses are said to be well 
 centred, and in that way we get rid of most of the prismatic 
 color. Another point that wants attention is the mounting. Ab- 
 solute steadiness is required for close observation. I used to put 
 mine upon a post set firmly in the ground. The equatorial ar- 
 rangement for mounting is described in nearly every work on 
 telescopes." 
 
 Thermometers, Hard-rubber. — This instrument has been made 
 by riveting the rubber to a thin strip of steel, about a foot in 
 length and J in. in width. The bottom of this was held fast, 
 while the top was free to move, and so to indicate the temperature 
 on a graduated arc. This one, now in use, has a range from zero 
 to 90° Fahr., and is as sensitive as the common mercurial thermo- 
 meter. It is well adapted for the ordinary range of the atmo- 
 sphere, but is not suitable for indicating high degrees of heat, 
 as the rubber softens at about 200° Fahr. Another thermometer 
 was made by perforating a thin strip of steel, at intervals of an 
 inch, and placing upon it a strip of rubber compound when in a 
 plastic state. This was coiled, with an intermediate strip of me- 
 tal, which forced the rubber through the holes It was then vul- 
 canized in the usual manner ; and when cold, the intermediate 
 strip was withdrawn, leaving an open space between the coils. 
 Tills saved the trouble of riveting, and gave to the rubber an un- 
 broken and smooth surface. The coil is held last at the centre, 
 
156 PRACTICAL TECHNOLOGY. 
 
 and the outer end is left free to move. Another thermometer was 
 made of glass and hard rubber, the latter in the form of an arc, 
 being riveted at both of its ends to a glass plate, which formed 
 the chord. 
 
 Thermometers. — To change Fahrenheit degrees into Centi- 
 
 _, ^ 5 (F.-33) ^, . ^ . .^ , , . „ 9 C. . „„ 
 
 grade: C.= . Centigrade mto Fahrenheit: F.=—- — ^ 32. 
 
 y 5 
 
 9R. 
 
 Reaumur into Fahrenheit : F.= '-I- 32. Fahrenheit into 
 
 4 ' 
 
 Keaumur : K. = • Keaumur into Centigrade : C. = — — • 
 
 4C. 
 Centigrade into Reaumur : R.=-r- 
 
 
 
 RECIPES FOR THE PREPARATION OF WOOD. 
 
 Dyeing Woods. — All light woods may be died by immersion. 
 A fine crimson is made as follows : Take 1 lb. ground Brazil, boil 
 in 3 quarts of water, add ^ oz. cochineal, and boil another half 
 hour ; may be improved l)y washing the wood previously with ^ 
 oz. saffron to 1 quart water. The wood should be pear wood or 
 sycamore. Purple satin : 1 lb. logwood chips, soak in 3 quarts of 
 water, boil well an hour ; add 4 ozs. pearlash, 2 ozs. powdered 
 indigo. Black may be produced by copperas and nutgalls, or 
 by japanning with two coats of black japan, after which varnish 
 or polish, or use size and lanii)l)l!ick j)r<!vions to laying on ja- 
 pan. A blue stain : 1 lb. oil of vitriol put in a glass bottle with 4 
 ozs. indigo ; lay on the same as black. A lino green : 3 pints of 
 the strongest vinegar, 4 ozs. best powdered verdigris (poison), ^ 
 oz. sap-green, ^ oz. indigo. A bright yellow may be stained with 
 aloe ; the whole may be varnished or i)olishcd. 
 
 F^iJONY, Artificial. — Treat sea-weed for 2 hours in dilute sul- 
 l)]iuric acid. Of the charcoal thus obtained taki^ 16 parts ; dry, and 
 grind it. Add licjuid glue 10 parts, giitta-])erclia 5, india-rub- 
 ber 2J-, the last two dissolved in naphtha, 'i'hen add coal-tar 10, 
 ))ulverized Hulphiii- 5, piilveriz(>d alum 2, j)ow(len'(l resin 5, and 
 iieat tlic! mixture to 300' Fahr. This when hard will take a pol- 
 isli equal to ebony, and is the same in color and liardnesa. 
 
 Oak, To color orange-ycdlow. — Wuh thv. wood with a mixture 
 of tallow 3 ozs., wax !j oz., and turpfnlinc 1 pint, mixed by heat- 
 ing together and stirring. A])i)ly in a warm room until n dull 
 polish is aci|uin(|. Thi-n coat, after an lK)ur, with thin polish, and 
 repeat until the dcsiicd depth and brilliancy of tone is obtained. 
 
 ScKKWs, WoitiiK.N, To season. — Bore a liole longitudinally 
 through tlm centre of the scniw ; it will not In- ii\>i to crMck so 
 badly in seasoning, l)ecause then the air can g«it to tlie centre of 
 the wood, tiie sap t scapes therefrom, the centre of the wood con- 
 
PRACTICAL TECHNOLOGY. 157 
 
 tracts, and tlie strain on the outside is lessened. Of course, the 
 larger the hole.the better for the seasoning process ; but it should 
 not, and need not, be large enough to materially weaken the screw. 
 If, in addition, you can boil the screw in water, the job will be 
 bettered ; if boiled in oil, it will be complete. 
 
 Veneers, Artificial, To make. — Soak the wood for 24 hours, 
 »and boil for ^ liour in a 10 per cent solution of caustic soda. Then 
 wash out the alkali, when the wood will be elastic, leather-like, 
 and ready to absorb the desired color. After immersion in the 
 color-bath, dry between sheets of papex under sufficient pressure 
 to preserve the shape. 
 
 Veneers, Steaming. — Blocks of wood intended for veneers 
 may be steamed in a solution of borax and ammonia. They will 
 then become soft and easy to cut, and, beside, will retain their 
 flexibility for a long time. 
 
 Wood, A liquid. — Sawdust can be converted into a liquid 
 wood, and afterward into a solid, flexible, and almost indestruc- 
 tible mass, which, when incorporated with animal matter, rolled, 
 and dried, can be used for the most delicate impressions, as well 
 as for the formation of solid and durable articles, in the following 
 manner : Immerse the dust of any kind of wood in diluted sul- 
 phuric acid, sufficiently strong to affect the fibres, for some days ; 
 the finer parts are then passed through a sieve, well stirred, and 
 allowed to settle. Drain the liquid from the sediment, and mix 
 the latter with a proportionate quantity of animal offal, similar 
 to that used for glue. Roll the mass, pack it in moulds, and al- 
 low it'to dry. 
 
 Wooden Labels, Preservation of. — Thoroughly soak the pieces 
 of wood in a strong solution of sulphate of iron ; then lay them, 
 after they are dry, in lime-water. This causes the formation of 
 sulphate of lime, a very insoluble salt, in the wood. The rapid 
 destruction of the labels by the weather is thus prevented. Bast, 
 mats, twine, and other substances used in tying or covering up 
 trees and plants, when treated in the same manner are similarly 
 preserved. Wooden labels, thus treated, have been constantly ex- 
 posed to the weather during two years without being affected 
 thereby. 
 
 Wooden Taps, Preserving, for Casks. — The articles should be 
 plunged in paraffine, heated to about 248° Fahr. until no air-bub- 
 bles rise to the surface of the melted material. They are then al- 
 lowed to cool, and the paraffine is removed from the surface, when 
 nearly congealed, by thorough rubbing. Ta[)S thus treated will 
 never split or become impregnated with the liquid, and may be 
 used in casks containing alcoholic liquors. 
 
 Wood, Brown stain for. — Paint the wood over with a solution 
 made by boiliug 1 pint catechu (cutch or gambler) with 30 pints 
 water and a little soda. Dry, and then paint over with a solution 
 of bichromate of potash 1 pint, water 30 pints. By a little dif 
 ference in the mode of treatment, and by varying the strength 
 of the solutions, various shades of color may be given to these 
 materials. The colors will be permanent, and will tend to pre- 
 serve the wood. 
 
158 PRACTICAL TECHNOLOGY. 
 
 Wood, Preserving. — This process is valuable for rail way-slei.p- 
 ers. Steam the timber, and inject a solution of silicate of soda 
 for 8 hours. Then soak the wood for the same period in lime- 
 water. (Dr. Feuchtwauger's process.) 
 
 Wood, Preservative ])reparation for. — Mix 40 parts chalk, 50 
 resin, 4 linseed-oil, melting them tt)gether in an iron pot ; then 
 add 1 part of native oxide of copper, and afterward 1 part of 
 sulphuric acid. Apply with a brush. When dry, this varnish* 
 is as hard as stone. 
 
 Wood, To ebonize. — Collect lampblack from a lamp or candle on 
 a piece of slate. Scrape off the deposit, mix with French polish, 
 and apply to the object in the ordinary way. 
 
 Wood, To fire-proof. — Paint twice over with a hot saturated 
 solution of 1 part green vitriol and 3 parts alum. After drying, 
 paint again with a weak solution of green vitriol in which pipe- 
 clay has been mixed to the consistence of paint. 
 
 THE PREPARATION AND PRESERVATION OF 
 NATURAL-HISTORY SPECIMENS. 
 
 Anatomical Specimens, Preserving. — Glycerine will preserve 
 the natural colors of marine animals kept immer.<od in it. 
 
 BiKDS, Stuffing. — The following tools are required (see Fig. 1). 
 — First, there is the scalpel. This can be purchased for a small 
 sum from any maker of surgeon's instruments. The blade is 
 short and very .sharp, while the handle (not jointed) is long 
 enough to allow of a firm grasp. From the same maker, a 
 couple of jiairs of surgeon's scissors should also be obtained, one 
 quite small and sharp -pointed, the oth(>r of medium size ; also 
 two or three spring forceps of various dimensions. A small pair 
 of pliers for clip])ing wire is required, some 8])ools of cotton 
 (Xos. 10, ;}0, and 100), a quantity of excelsior and tow, some cot- 
 ton batting, a little i)re]>iire(l glue, a number of jjieces of wire 
 about fifteen inclies long, and straight (.size No. 20 or there- 
 abouts), a box of dry oatmeal, and some ar.senical soap. This 
 last can generally l)e obtained of druggists, or, if not, can be 
 mad<! of carl)onatc of pota.sh '.] ounces, white arsenic, white soap, 
 and air-slaked lime, 1 ounce each, and jiowdered camphor, -?g 
 of an ounce, 'i'liis is combined into a thick ])aste with water, 
 and ai)])lied us below descriWeii, with a small paint-brush. It 
 should be nuirked as poison, and kept scruimlously out of the 
 reiicli of children or pet animals. 
 
 If th(! i)inl has been shot, immediately afterward all the holes 
 made in its hody, as well as the mouth, sliould l)e plugged with 
 cotton, in order to prevent the escape of blood or lupiids. Opera- 
 tions should not lie begun for twenty four liours, so that the l)ody 
 may havt; ample time t(» .stilleu and the blood to coagulate. It is 
 
PRACTICAL TECHNOLOGY. 
 
 159 
 
 well during this period to inclose the bird, head downward, in a 
 cone of paper, so that the feathers will be held smooth. 
 
 The first process is skinning. In commencing, the left hand is 
 used to part the feathers, exposing the skin from the apex of the 
 breast-bone to the tail. With the scalpel held like a pen, a free 
 incision is made between these points, care beinpf taken to divide 
 the skin only, without cutting into the flesh. The skin is then 
 pressed apart, and oatmeal dusted into the cut, in order to absorb 
 any fluids which may escape. Careful lifting of the skin clear 
 of the flesh follows, until the leg is reached, when the scalpel is 
 again used to disarticulate the thigh-joints. The bone of each 
 thigh is then exposed for its whole length, by pushing back the 
 skin, and the meat removed, when the bone is replaced, and the 
 other thigh treated in similar manner. 
 
 PIG. 1.— TAXIDERMICAL IJIPLEMENTS. 
 
 The skin is next detached, to the wings, which are cut from 
 the body at the joint next the same, and the bones scraped clear 
 of meat. Then the neck is divided, so that the skin, with the 
 head attached, can be peeled from the entire body clear to the 
 root of the tail. The last is bent toward the back with the left 
 hand, the finger and thumb keeping down the detached parts of 
 the skin on each side of the vent. A deep cut is then made 
 across the latter until the back-bone, near the oil-gland at the 
 root of the tail, is exposed. Sever tlie back-bone at the joint. 
 This detaches the body, which may be removed and thrown 
 aside, while the root of the tail, with the oil-gland, is left. Great 
 care is needed in this operation, as, if not enough bone be left at 
 
160 
 
 PBACTICAL TECHNOLOGY. 
 
 its root, the tail will come out ; but all fleshy matter should be 
 neatly dissected away. 
 
 The neck need not be split or in any wise cut. The skin is 
 merely pulled over the flesh, as a glove is removed from the 
 finger, until the skull is exposed and appears as in the sketch, 
 Fiji. 2. With the point of the knife, remove the ears ; and on 
 reaching the eyes, carefully separate the lids from the eyeballs, 
 cutting neither. It requires very delicate and slow work at this 
 point, so as not to injure the eyelids. Then scrape out the eye 
 cavities, and cut away the flesh of the neck, removing: at the 
 same time a small portion of the base of the skull. Through 
 the cavity thus made extract the tongue and brains, and after 
 cleaning away all fleshy matter, paint the eye orbits with arseni- 
 
 FIO. 2. — MODK OK ATTACmNci THE FALSE BODT 
 
 ciil soap, and stuff them tightly with cotton. Care should be 
 taken not to detach the skin from the l)ill, as it is necerisary to 
 leiivr- the skull in ))lace. Finally, fill the interior of the skull 
 wiili tow (never with cotton), aft(^r coating internally with the. 
 j)repiired soap. 
 
 Tlie skinning operation being now c()m])lcted, the stuffing is 
 next proceeded witli. To pnipare for this, the bird, before being 
 skinned, sliould liave been measured, first as to its girth about 
 the liody, and second as to its h;ngth from root of tail to top of 
 skull, following tile sliajjc of" tlu^ form. From these data an arti- 
 ficial hody of the right dimensions is constructed and inserted as 
 follows: On a piece of straight wire, e<|ual in length to the la,st 
 uieasurement above jur-ntioned, a hunch of exc(dsior is secured 
 
PRACTICAL TECHNOLOGY. 
 
 161 
 
 bv repeated -windinof with stout thread. This bundle, which is 
 represented iu our Fig. 2, is moulded to a shape resembling that 
 of the bird's body, and its girth is regulated by the similar 
 measurement already obtained from the bird itself. As will be 
 seen, it is attached at the end of the wire, the long protruding 
 portion of which serves as a foundation for the neck. The ex- 
 tremity of the wire is clipped by the pliers to a sharp point, and 
 then forced diagonally upward through the skull, on top of 
 which it is clinched flat. Cotton batting is then wound about the 
 wire between skull and body, until sufficient thickness is obtain- 
 ed to fill the skin of the neck. The position of the various parts 
 at this point is represented in Fig. 2. Painting the inside of the 
 skin with arsenical soap follows, and then the skin is drawn back 
 so as to envelop the false body, and a needle and thread are 
 thrust through the nostrils to make a loop for convenience in 
 haudlinor. 
 
 FIG. 3. — STUFFING THE LEGS. 
 
 The finest pair of forceps is employed to pull the eyelid skin 
 into place, to arrange the feathers, and to pull up the cotton in 
 the orbits so as to stuff the cavities out plumply. More cotton is 
 next pushed down the throat until the same is entirely filled. 
 Two pieces of wire — quite stout for large bird— are then sharp- 
 ened at one extremity. Taking the wire in one hand and guid- 
 ing it with the other, the operator shoves it into the leg, from 
 the ball of the foot up alongside the thigh bone, the skin being 
 turned back for the purpose. Cotton is then wound about both 
 wire and bone, in order to fill the thigh out naturally, and the 
 same process is repeated for the other side. The ends of the 
 wire below are left protruding in order to support the bird on a 
 perch, if such be desired. The upper ends are pushed clean 
 through the artificial body, from below up, and clinched on the 
 
162 
 
 PRACTICAL, TECHNOLOGY. 
 
 upper side. This secures the legs, which are afterward bent in 
 natural position (Fig. 3). The bird can now be set up — that is, 
 the wires stretching out below the claws can be wound about a 
 perch or pushed through holes in a board and clinched on the 
 under side. In the latter case, it will be necessary to spread the 
 claws and fasten them with pins. For small birds, the cut in 
 the bi-east need not be sewn uj) ; a chicken or larger fowl will 
 require a few stitches to hold the edges together. If the tail 
 feathers are to be spread, a wire is thrust across the body and 
 throuorh each feather, holding all in the proper position. The 
 wings are then gathered closely into the body, and two wires. 
 
 no. 4. — 'llli: I'.IKl) l-KKCAKKI) FOle DllYINO. 
 
 one from each side, are ])iishc(I in diagonally from ui>, down, and 
 through the skin of tlu' second joint (Fig. 4). The wings are 
 tliiis held, and tln' wires, as Wfll as tliat tliiougli the tail, are left 
 protruiling for an inch or more. A tnuchof glue within the eycv 
 lidH ])rej)areH the latter for the eyes. These must hi? purchased 
 from taxidermists, but for small birds <'ommon bla<'k beads will 
 aiis\v<;r. If plain glass beads can lie nhtaincid, by the aid of a 
 little piiint the student can easily imitate the ey(' of a diickeii. 
 .After tli(! eyes ai'e insertcMl, a sliai|) needle is used to pull the 
 lids around them and into pliKe. 
 
 '{"he <)|i(?rator must now, with a line pair of f(»rceps, carefully 
 
PRACTICAL TECHNOLOGY. 163 
 
 adjust the feathers, smoothing them down with a large camel's- 
 hair brush. This done, thread must be wound over the body 
 very loosely, beginning at the head, and continuing until all the 
 feathers are securely bound. The bird is then left to dry for a 
 day or two, when the thread is removed, the ends of wire cut oif 
 close to the body, and the work is complete. 
 
 Entomological Specimens, To preserve, from insect ravages. 
 — Place crystals of carbolic acid throughout the cabinets, and the 
 evaporation of the crystals will keep them thoroughly saturated 
 with carbolic acid vapors, which will kill all living insects therein. 
 
 Fish, To mount and preserve. — It is impossible to preserve 
 the iridescent tints ot the living specimens ; but before proceed- 
 ing to the operation of skinning, it may be stated that the 
 scales, as well as their color, may be preserved to a certain de- 
 gree by applying tissue-paper to them, which, from the natural 
 glutinous matter which covers the scales, will adhere firmly ; 
 this being allowed to remain until the skin has dried, may 
 easily l)e removed by moistening with a damp cloth. All small 
 fish should be mounted in section, while the larger varieties may 
 be preserved entire. Supposing the fish to be of such a size as 
 to be mounted in section, first it is necessary that it be as fresh 
 as possible, as the scales will become detached if decay set in. 
 Place the fish on one side, and cover the side uppermost with 
 tissue-paper, as above stated ; also extend the fins by means of 
 the same, and allow them to remain a few moments until fixed 
 and dry. Haviug provided yourself with a damp cloth, spread it 
 smoothly upon tlie table, and place the fish upon it, papered side 
 down. With the dissecting scissors, cut the skin along an oval 
 line, following the contour of the body, but a little below the ex- 
 treme dorsal edge and a little above the ventral one, and remove 
 the skin included within this line. The remaining skin must 
 now be detached from the flesh, beginning at the head and 
 separating it downward toward the tail. The spine must be 
 severed close to the head, and also at the tail, and the entire body 
 removed. All the flesh having been taken from the skin, and the 
 eyes removed, the inside must be wiped out and the preservative 
 (arsenical soap) applied. The skin should now be filled with 
 tow, very evenly placed. When filled, it should be laid, with 
 the open side down, upon a board of proper dimensions, and 
 fastened to it by small tacks, beginning at the head and fastening 
 the edges downward toward the tail. It should then be set aside 
 to dry. The paper is, after drying, removed, and eyes of wood 
 (painted to the proper colors, and not varnished) are inserted 
 with a little putty. Finally the skin should receive a coat of 
 colorless varnish, when the specimen is ready for the cabinet. 
 
 Sea-Weed, Preserving specimens of. — The best time to col- 
 lect is when the tide has just commenced to flow, after the low- 
 est ebb, as the sea weeds are then floated in, in good condition. 
 All specimens should be either red, green, purple, black, or 
 olive ; no others are worth preservation. 
 
 Mounting is done by immersing a piece of paper just below 
 the surface of the water, and supporting it by the left hand ; 
 the weed is then placed on the paper and kept in its place by the 
 
164 PRACTICAL TECHIVOLOGY. 
 
 left tliumb, while the right hand is employed in spreading out 
 the branches with a bone knitting-needle or a camel's-hair pen- 
 cil. If the branches are too numerous, which will be readily 
 ascertained by lifting the specimen out of the water for a mo- 
 ment, pruning should be freely resorted to, by cutting off erect 
 and alternate branches, by means of a sharp-pointed pair of scis- 
 sors, close to their junction with the main stem. When the 
 specimen is laid out, the paper should be raised gradually in a 
 slightly sloping direction, care being taken to prevent the 
 branches from running together. The delicate species are much 
 improved in appearance by reimmersing their extremities before 
 entirely withdrawing them from the water. The papers should 
 then be laid Hat upon coarse bibulous paper, only long enough to 
 absorb superfluous moisture. If placed in an oblique direction, 
 the branches are liable to run together. They should be then 
 removed and placed upon a sheet of thick white blotting-paper, 
 and a piece of washed and j^ressed calico placed over each speci- 
 men, and then another layer of thin blotting-paper above the 
 calico. Several of these layers are pressed in the ordinary way, 
 light pressure only being used at first. The papers, but not the 
 calico, may be removed in six hours, and afterward changed 
 every 24 hours until dry. If the calico be not washed, it fre- 
 quently adheres to the algiP, and if the calico be wrinkled it pro- 
 duces corresponding marks on the paper. The most convenient 
 sizes of paper to use are those made by cutting a sheet of paper, 
 of demy size, into 16, 13, or 4 equal pieces. Ordinary drawing- 
 paper answers the pur]iose very well. For the herbarium, each 
 species should be mounted on a separate sheet of demy or cart- 
 ridge size. Toned paper shows off the specimens well, a neutral 
 tint answering best for the olive, pink for the red, and green for 
 the green series. 
 
 Skins of Small Animals, Dyeing. — The green hull of the 
 European walnut is turned to account in Euro])e for dyeing furs 
 black, and the hull of (lur black walnut could probably be simi- 
 larly emi)loyed. The walnut hull is crushed and the juice 
 squeezed out from the ])ulp, with the addition of a little water. 
 A small (juantity of lime is added, and the dye is ready for use. 
 The color is extremely difficult of extraction, and attaches itself 
 very readily to any kind of hair, and it is used extensively as a 
 hair-dye. 
 
 Sti'FFIN*; small Quadtutpeds. — Begin by making a longi- 
 tudinal incision between the hind legs, extending (juite back to 
 tlie vent, the hair having been carefully i)artcd so that it may 
 not be cut. Do not cut into the abdominal cavity. The skin 
 can now be separated from the flesh and turned back as far as 
 the tliigli, whicli is sfvircd at the joint. When this is done on 
 botli sides, tliir gut should bo drawn out and severed at a short 
 (lisiance from tlie vent. The tail should also l)e disjointed at the 
 root. Tills being done, the skin can be loosened around the 
 body until the fore-legs are reached, when they also should be 
 dissevered. Tlie skinning now proceeds along the neck until 
 t!ie skull is reiiched. Here <-nnsiderable care is necessary to re- 
 move the skin without damage to the ears, eyelids, and lii)H. 
 
PRACTICAL TECHNOLOGY. 
 
 165 
 
 The skin is left attached to tlie skull ; when the operation has 
 proceeded far enough to expose the muscles of the jaws, the 
 skin must be separated from the body at the first joint of the 
 neck. The tongue, eyes, and muscles, remaining attaclied to 
 the head, are now to be carefully removed, and the brain taken 
 out from an opening in the back of the skull cut through for 
 that purpose. To make this opening, amateurs can use a small 
 gimlet or bit with very small animals, and a large one as cir- 
 cumstances may demand. The legs are now to be skinned out 
 quite down to the claws, which completes the o^jeration of skin- 
 ning. During tlie entire process, all fluids escaping must be im- 
 mediately soaked up with cotton. As soon as the skin is re- 
 moved, it should be thoroughly rubbed with arsenical soap, not 
 omitting the inside of the skull and mouth cavities. 
 
 The following explanation of stuffing relates to a small ani- 
 mal such as the squirrel. Provide yourself with cotton, tliread, 
 and twine, also stuffing-forceps, a pair of pincers, a file, and 
 •wire-cutters. With the aid of the forceps (a pair of slender- 
 jawed pliers), supply the various muscles of the face and head 
 by inserting cotton both through the mouth and eyelids. Take 
 annealed iron wire and cut off 6 pieces : No. 1, two or three 
 inches longer than the total length of the body ; Xos. 2 and 3 
 for the fore-legs ; Kos. 4 and 5 for the hind-legs ; each of these 
 should be three inches longer than the limbs they are to 
 support ; No. 6, for a support for the tail, of the same propor- 
 tionate length as the others. With a large pair of scissors, cut 
 fine a c[uannty of tow, and with this, by the use of the long 
 forceps, stuff the neck to its natural dimensions. Taking wire 
 No. 1, bend it in four small rings, the distance between the two 
 outer representing the length of the body taken from the skin, 
 a, leaving one long end for a support to the head and neck, b (see 
 
 STUFFING ANIMALS. 
 
 figure). Mould tow about that part containing the rings, and, 
 by winding it down with thread, form an artificial body. 
 Sharpen the projecting end of the wire to a fine point with the 
 file, and insert it up through the tow in the neck, and thence 
 through the skull ; the skin should then be pulled over the 
 body. Wires No. 2 and 3 are placed next in position by insert- 
 ing them through the soles of the feet, up within the skin 
 of the leg, and through the body of tow, until they appear upon 
 the opposite side. With the pincers, bend over the end of each, 
 forming a hook ; the wires must then be pulled backward, thus 
 fastening the hooks firmly into the body. The loose skin of the 
 limbs should then be stuffed with cut tow, taking care to imitate 
 the muscles of the living subject. Nos. 4 and 5 can be fixed in 
 position after the same manner, unless the animal is to rest en- 
 
loG PRACTICAL TKCUNOLOGY. 
 
 tirely upon its rear (as in tlie case with the squirrel feeding) ; then 
 the wire must be inserted at the tarsal joint instead of at the 
 sole of tlie foot. If any depressions appear in the skin, they 
 must be stuffed out witli cut tow. Wire No. C should now be 
 inserted at the tip of tlie tail, and forced down within the skin, 
 hooking it into the body in the same manner as the leg-wires. 
 Stuff the tail to its proper dimensions with cut tow, and care- 
 fully sew up the incision along the abdomen. Having i)repared 
 a board about f inch thick, pierce in it two holes at the proper 
 distance apart for the reception of the wires (four holes will be 
 needed if the animal is to stand on all extremities) ; these must 
 be drawn through upon the under side until the feet rest close 
 upon the upper surface, when they should be clinched. The 
 different joints of the limbs can now be imitated by bending 
 the wire at the jiroijor i)oints. The eyes should next be placed 
 in position, and cemented in the orbits by a little putty. Care 
 should be taken in arranging the eyelid, for the expression de- 
 pends altogether upon this point. Clip off any superfluous wire 
 which may extend above the head with the wire-cutters. The 
 specimen should be placi^d In some locality free from moisture, 
 and allowed to dry thoroughly, when it is complete for the cabi- 
 net. 
 
 PAINTING, GILDING, AND VARNISHING RE- 
 CIPES. 
 
 Baij-OON Varnishes. — Mr. John Wise, the well-known aero- 
 naut, says : " There are two ways of preparing linseed-oil for bal- 
 loon varnish : llu; (juick and the slow process. The first is by 
 heating the oil up to a temju'rature at which it will ignite spon- 
 taneously. In order to secure it from burning up, it must be 
 lieated in an iron or copper vessel, witli a lid that can be closed 
 when it begins to omit dense white vapcir. If it is desired to 
 have it fast drying, from 4 to G ozs. litharge per gallon should be 
 boiled in it. Tliis process takes about one hour, ami renilers the 
 oil thick and tougli, giving a good body and glossy surface to 
 theclolh. The slow jjtoccss is to bi)il tlu- oil from 12to 20 hours, 
 keeping it at a temperature of alxiut 200 Fahr., incorporating 
 witli it, while boiling, i oz. suljdiate of manganese to each gal- 
 lon of oil. These varnishes should l)e api)H(d to the cloth tole- 
 rably hot. Tln're are other formulas, sucli as the incorporation 
 with the oil of snine birdlime. (Jum-elastic is also used to give 
 lli(! oil body and ehistlcity. NVlien I desirt! to make a balloon 
 extraordinarily close, I give it a (irst coating of c( nipound varnish 
 made ii]i of ('(pial parts whitis glue and glyc(;rine." 
 
 JiKONZK, (Joi.i), for furniture. — (fold bronze for furniture is a 
 mixture of copal varnish mixi,'d with gold-colon^d bronze-powder. 
 The last is bisulphatc of tin. 
 
 BiUHiiKs, Care of varni.shing. — A good way to keep brushes 
 
PRACTICAL TECHNOLOGY. 167 
 
 is to suspend them by the handles in a covered can, keeping the 
 points at least half an inch from the bottom, and apart from each 
 other. The can should be filled with slowly-drying varnish up 
 to a line about i\ inch above the bristles or liair. The can should 
 I hen be kept in a close cupboard, or in a box fitted for the pur- 
 pose. As wiping a brush on a sharp edge will gradually split 
 the bristles and cause them to curl backward, and eventually 
 ruin the brush, the top of the can should have a wire soldered 
 along the edge of the tin, turned over, in order to prevent injury. 
 Finishing brushes should not be cleansed in turpentine, except in 
 V'xtreme cases. When taken from the can, prepare them for use 
 by working them out in varnish ; and before replacing them, 
 eleanse the handles and binding in turpentine. 
 
 Colors, Naturally transparent. — These are terra de sienna, 
 asphaltum, dragon's blood, carmine, rose-pink, chemical brown, 
 all the lakes, gamboge, and all the gums. Semi-transparent : um- 
 ber, Vandyke brown, chrome red, emerald green, Brunswick 
 green, ultramarine, indigo, and verdigris. Transparent colors j.re 
 purer if ground in water ; allow them to settle, pour off the top 
 part of the settlings : mix that with more water ; let it settle, and 
 take the top half of that, which will be free from all sand and 
 grit. Turpentine makes transparent colors work crumbly. 
 Bleached boiled oil or white varnish is the best vehicle for flow- 
 ing evenly. 
 
 Gilding without a Battery. — Dissolve 20 grains chloride 
 of gold in a solution of cyanide of potassium, 1 oz. to 1 pint pure 
 water. Put the solution of cyanide of gold in a glass or porce 
 lain jar ; place in it the articles to be gilded in contact with a 
 piece of bright zinc, in the solution near them ; the process will 
 he hastened by a gentle warmth. If the gold is deposited on the 
 zinc, rub a little shellac-varnish on it. The chloride of gold 
 may Ije prepared by dissolving gold in aqua regia in the propor- 
 tions of 16 grains gold to 1 oz. acid, and evaporating to dryness. 
 
 Gilding on Glass. — Mix powdered gold with thick gum- 
 arabic and powdered borax ; with this trace the design on the 
 glass, and then bake it in a hot oven. The gum is thus burned 
 and the borax vitrified, and at the same time the gold is fixed 
 on the glass. To make powdered gold, rub down gold-leaf with 
 pure honey on a marble slab. Wash the mixture, and the pre- 
 cipitate is the gold used. 
 
 Japan, Black and flexible. — Take burnt umber 4 ozs. , asphal- 
 tum 2 ozs., boiled oil 2 qts. ; dissolve the asphaltum first in a 
 little oil, using moderate heat; then add the umber (ground in oil), 
 and lastly the rest of the oil, and incorporate thoroughly. Thin 
 with turpentine. 
 
 Loom-Harness, Varnish for. — Mix linseed-oil 2 gals., gum- 
 shellac 2i lbs., litharge 2 lbs., red-lead 1 lb., umber 1-| lbs., 
 sugar of lead 1^ lbs. 
 
 Machinery, Painting. — The following colors contrast hand- 
 somely : 1. Black and warm brown. 2. Violet and pale green. 
 3. Violet and light rose-color. 4. Deep blue and golden brown. 
 5. Chocolate and bright blue. 6. Deep red and gray. 7. Maroon 
 
168 PBA.CTICAL TECHNOLOGY. 
 
 and warm green. 8. Deep blue and pink. 9. Chocolate and pea- 
 green. 10. Maroon and deep blue. 11. Claret and buflf. 13. 
 Black and warm green. 
 
 M.AJiBLE, To stain. — Blue, solution of litmus ; green, wax col- 
 ored with verdigris ; yellow, tincture of gamboge or turmeric ; 
 red, tincture of alkanet or dragon's blood ; crimson, alkantjt in 
 turpentine ; flesh, wax tinged with turpentine ; brown, tincture 
 of logwood ; gold, equal parts of verdigris, sal-ammoniac, and 
 sulphate of zinc in fine powder. 
 
 Paint without oil. — Break an egg into a dish and beat slight- 
 ly. Use the white only, if for white paint ; then stir in coloring 
 matter to suit. Red-lead makes a good red paint. To thin it, 
 use a little skimmed milk. Eggs that are a little too old to eat 
 will do for this very well. 
 
 Paint, Reddish-brown, for wood. — The wood is first washed 
 with a solution of 1 lb. cupric sulphate in 1 gallon water, and 
 then with 4 lb. potassium ferrocyanide dissolved in 1 gallon wa- 
 ter. The resulting brown cupric ferrocyanide withstands the 
 weather, and is not attacked by insects. It may be covered, if 
 desired, with a coat of linseed-oil varnish. 
 
 Paint to stand the action of hot water. — Clean the metal 
 with turpentine or benzine. Then mix white-lead, carriage-var- 
 nish, and spirits of turpentine, and give the metal two thin coats, 
 and then a thick coat of white-lead and carriage-varnish, applied 
 as quickly as possible. 
 
 PcTTY, Inde.structible. — Boil 4 lbs. brown umber in 7 lbs. 
 linseed-oil for 2 hours ; stir in 2 ozs. wax ; take from the fire, 
 and mix in Hi lbs. chalk and 11 lbs. white-lead, and incor- 
 porate thoroughly. 
 
 Iron Sukfaces, Painting. — In mixing paints for iron surfaces, 
 it is of the first importance that the best materials only be used. 
 Linseed-oil is the best medium, when free from admixture with 
 turpentine. A volatile oil, like turpentine, can not be used with 
 advantage on a non-absorbent surface like that of iron, for the 
 rea.sf)n tliat it leaves the j»aint a dry scale on the outside, which, 
 having no cohesion, can be readily crumbled or washed away. 
 Linseed-oil, on the other liand, is peculiarly well adapted for this 
 purpose. It df)es not evaporate in any perceptible dejfree, but the 
 large percentage of linolein which it contains combines with the 
 oxygen of the air, and forms a solid, translucent substance, of resi- 
 nous appearance, which possc.-^sj's much toughness and elasticity, 
 and will not crack or blister by reason of the expansion and 
 contraction of the iron witli variations of temperature. It is, 
 moreover, remarkably adhesive, is impervious to water, and is 
 very difficult of solution in essential fiils, spirits, or naphtha, and 
 even in bisulphide of carl>on. Another important advantage of 
 linolein la that it expands in dryinfr. which ]M'(Miliarly adapts it 
 to iron surfaces ; since cracks, however minute, resulting from 
 shrinkage, exjKise enough of the met«l to afford a chance ifor cor- 
 rosion, which will spread in all directions, undermining the paint 
 and causing it to scale off, beside discolorinjr it. In selectiufi' a 
 paint for iron, meclianical adhesion is a consideration of the first 
 
PRACTICAL TECHNOLOGY. 169 
 
 importance. Pitchy or bitumiuous films are especially effective 
 as regards their adhesion to iron ; for example, solutions ot as- 
 phalt or pitch in petroleum or turpentine. These are also very ef- 
 fective as regards continuity, owing to the fact that, in drying, 
 they form plastic films, which yield with the expansion and con- 
 traction of the iron, and manifest no tendency to crack. If the 
 surface is rusty, they penetrate the oxide scale, and envelop the 
 particles very effectually, making them a portion of the paint. 
 The solubility of such a film in water may be counteracted by 
 mixinor it with linseed-oil. The experiment may easily be tried 
 by mixing about 3 parts of Brunswick black with one of white, 
 red, or stone colored paint, the body of which is composed of red 
 or white lead or litharge. Red-lead is the best, for many reasons, 
 if finely ground and thoroughly mixed with linseed-oil. Any one 
 of several kinds of bitumen may be used, either natural mineral 
 asphalt, pine pitch, or artificial asphalt, such as gas-tar or the re- 
 siduum of petroleum distillation, in cases where the crude oil has 
 been distilled before being treated with acid. This gives a very 
 hard, bright pitcli, which is soluble in "once run" parafiine spirit, 
 and which makes the base of an excellent, cheap, and durable 
 paint for iron-work in exposed positions. Paraffine can be recom- 
 mended for all classes of iron-work which can be treated hot. The 
 most effective method of applying it is to heat the iron in vacuo, 
 in order to expand it and open its pores, when paraffine, raised 
 to the proper temperature, is run upon it. By this means the iron 
 is penetrated to a sufficient depth to afford a very effectual pro- 
 tection against oxidation, especially when a suitable paint is sub- 
 sequently applied. 
 
 Lacquer, Deep golden. — Seed-lac 3 oz., turmeric 1 oz., dragon's 
 blood i oz. , alcohol 1 pt. Digest for a week, frequently shaking. 
 Decant and filter. Golden : Ground turmeric 1 lb., gamboge 1| 
 ozs., ^um-sandarac 3ilbs., shellac f lb. (all in powder), recti- 
 fied spirits of wine, 2 gals. Dissolve, strain, and add 1 pt. of tur- 
 pentine varnish. Red: Spanish anatto 3 lbs., dragon's blood 
 1 lb., gum-sandarac Si lbs., rectified spirits 2 gals., turpen- 
 tine varnish 1 c^t. Dissolve, strain, and mix, as last. Pale brass : 
 Gamboge, cut small, 1 oz.. Cape aloes, ditto, 3 ozs., pale shellac 
 1 lb., rectified spirits 2 gals. Dissolve and mis as with the 
 golden. Lacquers, Cliancjing : I^acquers of this description 
 are called changing, because when applied to metals such 
 as copper, brass, or hammered tin, they give them a lustre 
 approaching that of the precious metals. Mix 4 ozs. of the 
 best gamboge in 32 ozs. of spirits of turpentine ; in another 
 vessel, mix 4 ozs. of dragon's blood witli same quantity of 
 turpentine, and in a third vessel, 1 oz. of annotto with like amount 
 of spirits. Keep the vessels exposed to the sun, in a warm place, 
 for a fortnight, when the contents will be fit for use. By 
 mixing these, any desired tint can be obtained. Another 
 deep golden : Strongest alcohol 4 ozs., Spanish anatto 8 grains., 
 powdered turmeric 2 drachms, red-saunders 12 grains. Infuse 
 this mixture in the cold for forty-eight hours, pour off the clear, 
 and strain the rest; then add powdered shellac A oz., sandarac 
 1 drachm, mastic 1 drachm, Canada balsam 1 drachm. Dis- 
 solve in the cold by frequent agitation, laying the bottle on its 
 side to present a greater surface to the alcohol. When dissolved. 
 
1 70 PRACTICAL TECHNOLOGY. 
 
 add 30 drops of spirits of turpentine. Pale tin : Strongest 
 
 alcohol 4 ozs. , powdered turmeric 2 drachms, hay saJEfrou 1 
 
 scruple, dragon's blood, in powder, 2 scruples, red saunders i 
 
 scruple. Infuse, and add shellac, etc. , as to the last-described deep 
 
 golden. When dissolved, add 40 drops of spirits of turpentine. 
 Lacquer should always stand till it is quite fine before it is 
 used. 
 
 Letteking, Sign-painter's scale for. — The following is a con- 
 venient table for sign-painters or others who have occasion to 
 make lettering. Supposing the height of the capital letters to be 
 ten, the widths are as follows : B, F, P, ten ; A, C, D, E, G, H, 
 K, N, 0, Q, R, T, V, X, and Y, eleven ; I, five ; J, eight ; S and 
 L, nine ; M and W, seventeen ; Z and &, twelve. Numerals : 1 
 equals five ; 2, 3, 5, 7, 8, nine ; 4, eleven ; 6, 9, 0, ten. Lower- 
 case letters (height six and a half) : Width : a, b, d, k, p, q, x and 
 z, seven and a half ; c, e, o, s, seven ; f, i, j, 1, t, three ; g, h, n, 
 u, eight ; m, thirteen ; r, v, y, six ; w, ten. 
 
 Putty, Old, in sashes, To soften. — Run a red-hot iron over it : 
 it will peel off easily. 
 
 Varnish, Black. — Alcohol 1 qt., aniline blue 184.8 grs., 
 fuchsin 46.2 grs., naphthaline yellow 123.2. Dissolve by agita- 
 tion in less than 12 hours. One application is sufficient. The 
 mixture should be filtered when it will not deposit. 
 
 Varnish, Cheap gold. — The following is a cheap substitute for 
 the ex])en8ive gold varnish used on ornamental tin-ware. Tur- 
 pentine + gallon, asphaltum I gill, yellow aniline 2 ozs. , um- 
 ber 4 ozs., turpentine varnish 1 gal., and gamboge -k lb. Mix 
 and boil for ten hours. 
 
 Varnish, Copal, To make. — Dissolve 1 pt. camphor, by weight, 
 in 12 pts. ether, then add best copal resin (pulverized) 4 pts., and 
 place in a well-stoppered bottle. When the copal has partly dis- 
 solved and has become swollen, add strong alcohol 4 pts., oil of 
 turpentine i pt. Shake, and allow to stand for a tew hours. 
 This makes an excellent varnish. 
 
 Varnish for Maps. — Take equal parts genuine Canada balsam 
 and oil of turpentine ; mix. Set the bottle in warm water, and 
 agitate until the solution is perfect ; then set in u warm place a 
 week to settle, when pour off the clear varnish for use. Before 
 using, cover the map with a thin solution of pure glue. 
 
 V.XRNisn, Parisian. — Dissolve 1 part of .shellac in 3 to 4 parts o| 
 alcohol of 92 per cent in a water-bath, and add cautiously-distill- 
 ed water, until a curdy mass separates out, which is collected 
 and i)reHse(l between linen. 'Vho liquid is lilt<;red through paper, 
 all the alcohol reinove<l liy distillatinn fmiii the water-bath, and 
 the resin removed and dried at 100*^ Centigrade, until it ceases to 
 lose weight. Dissolve it in double its weight of alcohol of 96 per 
 cent, and i)erfume with laveiuler oil. 
 
 VV.\lni:t Stain for Wood.— Water I (|t., washing soda 1^ 
 ozs., Vandyke br.wn 2* ozs., bichromate of potash i oz. Boil 
 lor ten minutes, and apjtly with a brush, either hot or cold. 
 
PRACTICAL TECHNOLOGY. 
 
 171 
 
 Whitewash, To improve. — Add a strong solution of sulphate 
 of magnesia. 
 
 Wood, Red stain for. — A permanent and handsome reddish 
 color may be given to cherry or pear tree wood by a coat of a 
 strong solution of permanganate of potash, left on a longer or 
 shorter time according to the shade required. 
 
 HINTS ABOUT DRAWING AND SKETCHING. 
 
 Camera Ltjcida, The.— This is probably the most reliable op- 
 tical device employed for copying. The principle of its construc- 
 tion will be understood in tlie diagram marked 2 in the engrav- 
 ing. The glass is simply a four-sided prism, having one right 
 angle, one of 135°, and two of 67^°. When disposed as repre- 
 sented, the rays from the object pass into it without any appreci- 
 able refraction, and are totally reflected from the lower inclined 
 
 FIG. 1 —THE CAMERA LUCIDA. 
 
 side, and again from the upper inclined side, emerging near tha 
 summit in a direction almost perpendicular to the top face, so 
 that the eye sees on the paper placed beneath an image of the 
 object. If the image be traced by the pencil, a very correct out- 
 line, not reversed, is obtained. The use of the device requires 
 practice. The nearer the object copied is brought to the prism, 
 the larger is its image, and vice versa. 
 
172 
 
 PRACTICAL TECHNOLOGY. 
 
 A simple method of constructing the camera Uicida is shown in 
 Fig. 2, and is the invention of Mr. H. 
 E. Mead, artist of the Scientific Ame- 
 rican. The prism can be obtained at a 
 small cost from any optician, and the 
 rest of the apparatus any one can cut out 
 of black walnut with a knife, and per- 
 haps a gimlet. The thumbscrews used 
 are of brass, of the kind employed for 
 shutter-fastenings, and can be procured 
 of any hardware dealer for a few cents 
 eacli. B is the prism, and A is a sec- 
 tion of one of the joints, showing how 
 the apparatus may be easily adjusted. 
 A movable rod, secured by a thumb- 
 screw, regulates the height ot the prism, 
 and the single clamp shown secures it 
 to the tabk". The cost of the whole is 
 about seven dollars. 
 
 Drawing-Board, Reflecting. — A flat 
 board is provided, with two uprights, 
 both of which, with the board, are 
 grooved to hold a pane of glass in a per- 
 l)cndicular jjosition. The drawing to be 
 copied is secured to the board on the left 
 of the glass, and the blank paper is fas- 
 tened on the right. The artist now 
 PIG. 2.— A SIMPLE CAMERA stands to the left, as represented in the 
 LuciDA. illustration, and looks down upon the 
 
 glass at a very oblique angl(\ The original drawing is re- 
 flected from the ])olish('d surface of the pane to his eye, and at 
 the same time he sees tlie white ])aper through the transparent 
 glass, Bo that the lines of the model appear transferred, but 
 reversed, upon the paper. These are followed with a pencil, 
 and the outline is made. 
 
 Drawino, Colors used in mechanical. — The annexed table 
 shows different materials, and the colors used to denote them : 
 
 Cast-iron, ... Paine's gray and a little Indian ink. 
 
 " (another tint) Ordinary neutral tint. 
 " " Prussian blue and Indian ink. 
 
 Prussian blue (or cobalt). 
 A ]>ur])le made by mixing crimson lake 
 
 and Prussian blui-. 
 <ianibi)ge or yellow ciidrniuni. 
 Iniiian red mixed willi a little lake, 
 liurnt umber. 
 Indian hmI. 
 Indian yellow or cadmium, toned with 
 
 white! 
 Chinese white ami Indian ink, toned 
 
 with yellow. 
 Broken, irregular straight lines, with 
 
 li(juid copix-raH, 
 
 Wrought-iron, 
 Steel, 
 
 <iun-metal. 
 ('opper, 
 \Vo<.d, 
 Brick (red), 
 " (yellow), 
 
 Stone color, 
 
 Water, 
 
PRACTICAL TECHNOLOGY. 
 
 178 
 
 Paper, Transfer. — A good transfer paper for copying monu- 
 mental inscriptions and metallic patterns may be made by rubbing 
 
 A REFLECTING DRAWING-BOARD. 
 
 a mixture of black-lead and soap over tlie surface of common 
 silver paper . 
 
 Paper, Tracing, Temporarily trnnsparent. — This is made by 
 dissolving castor-oil in absolute alcohol, and applying the liquid 
 to the pajjer with a sponge. The alcohol speedily evaporates, 
 leaving the paper dry. After the tracing is made, the paper is 
 immersed in absolute alcohol, which removes the oil, restoring 
 the sheet to its original opacity. 
 
 Paper, Tracing, that can be washed. — This is prepared by 
 first saturating writing-paper with benzine, and then immedi- 
 ately coating it lightly with a varnish composed of boiled bleached 
 linseed-oil 20 parts, lead shavings 1 part, oxide of zinc 5 
 parts, Venice turpentine i part. Mix, boil for 8 hours, and, 
 after cooling, add white gum-copal 5 parts, and gum-sandarac i 
 part. 
 
 Pantagraph, The. — This consists of four rulers, jointed toge- 
 ther at their intersections, and having, at two of the angles, sup- 
 ports terminating in round points or smoothly-running casters. 
 At one of the other angles is a weight to which the apparatus is 
 pivoted, and which holds it in place, and at the fourth corner is 
 a tracing-point, shown in the hand of the operator. Directly 
 across the frame thus made, and pivoted at its ends to the centres 
 of two of the bars, is a fifth bar, through the middle of which 
 passes a pencil. Along half the length of the two side-bars, and 
 
174 
 
 PKACTICAl, TECHNOLOGY. 
 
 also of the central bar, are made perforations, so that the length 
 of the rulers can be shortened as rendered necessary. The tracmg 
 point is moved over the outline to be followed, and its motion is 
 communicated to the series of rulers, which, by a kind of paral- 
 lel movement actuate the pencil to describe precisely the same 
 
 THE PANTAGRAPH. 
 
 line, equal in dimension to thiit of the co])y, or enlarged or re- 
 duced. Tlie scales of the two drawings are to each other as the 
 distances of the pencil and of the tracing-point from the pivot, 
 and these distances are adjusted by altering the position of the 
 joints in the holes. 
 
 Pencils, Copvinc, To make. — Pencils are sold by stationers, 
 the marks of which maybe copied in the same manner as writing 
 made by the pen with ordinary copying-ink. The method of 
 lir('i)ariiig the leads is as follows : A thick paste is made of gra- 
 ])hite. linely ]>uiveri/.ed kaolin, and a very conceut rated solution 
 of aniline blue, soluble in water. The mixture is pressed into 
 cylinders of suitable size and dried, when it is ready for use. (Slum 
 arable may be substituted for the kaolin. 
 
 St:N DuAWiNf;. — Draw with a ])eMcil on a piece of tracing- 
 paper the desired design ; go over the lines with very blaek ink, 
 turn tlie paper over, and ffjjlow the lines also witli ink on the 
 reverse side ; fasten tli«' paper by the corners to a pane of clear 
 glass. Make a solution f)f .J oz. bichroniati^ of potash in 2 ozs. 
 hot water, strain \\hen eold, aiul with this bi'usli over the ])a])er 
 or silk on whiih the design is to l)e printed. Plac<! the material 
 t liuH pre]>ared under the ])!i])er on the glass, and <himp all together. 
 f'^.xpose the wlioh- to bright sunliglit, glass uppermost, then design, 
 tlien biehromate paper ; in a few inr)ments, the design will be print- 
 
PKACTICAL TECHNOLOGY. 
 
 175 
 
 ed deeply. Wash and soak for a short time in clean water (to 
 fix), dry, and press with a warm fiat-iron. 
 
 Ruler, Perspective. — This is a simple arrangement for draw- 
 ing lines in correct perspective. It consists in three arms of 
 equal length pivoted together at one end by a screw-clamp. Two 
 pins are inserted in the drawing-board, against which two arms of 
 the ruler abut. The angle of these arms and the position of the 
 pins are governed by the distance required for the vanishing- 
 
 THE PERSPECTIVE-EULER. 
 
 point, as the greater the angle, the further the same is removed, 
 and vice versa. Once adjusted, the parts are clamped firmly to- 
 gether, and the lines ruled by the upper side of the arm which 
 rests upon the paper. The arms at an angle are kept in contact 
 with the pins, and the ruling arm is moved up or down the paper. 
 
 Sketching-Frames. — A square frame is hinged to the top of 
 an ordinary drawing lap-board, so that it will stand in an upright 
 position (as in Fig. 1). Across this is stretched a number of 
 threads or wires at equal distances apart so as to divide the inte- 
 rior space into small squares. The paper on the board is simi- 
 larly divided by light pencil-lines ruled over the surface. In 
 making the sketch, the artist draws so much of the view as he 
 sees through one of his squares in the frame, into the correspond- 
 ing ruled square on the paper, and thus having a large number 
 of straight lines to refer to is very readily enabled to locate the 
 details of the picture. It is, however, necessary to use but one 
 eye when looking at the landscape, and to keep this eye always 
 at the same place, for which purpose an additional eye-piece 
 may be added, simply consisting of a ring supported on a stand. 
 
 Sketching, Out Door, Simple apparatus for. — Provide a 
 
176 
 
 PEACTICAL TECHNOLOGY. 
 
 small table with, drawer ; mount two grooved movable uprights 
 at one end, with glass between the grooves ; place an upright 
 with a small eye-hole at the opposite end of the table, as shown 
 in the engraving. Wash the glass with a thin solution of gum 
 
 THE SKETCHING-FRAMB. 
 
 arable and rock candy (20 parts ffum to 1 o£ candy). When the glass 
 is dry, it is ready for use. Look through the small hole to get the 
 object subtended by the glass, and with a soft crayon outline the 
 subject on the prepared surface ; remove the glass and lay it 
 
 ii; -K 1. 1 c III M 
 
 M'l'AltATt'H. 
 
 over your Hkclcli. If you rciiuiri' lliu outline, you .sliouM liave a 
 second plate of glass, and trace over it the reverse way with 
 cliarcoul. then lay your paper on, and a little gentle rubbing will 
 transfer the outline. 
 
PRACTICAL TECHNOLOGY. 
 
 177 
 
 Tracing-Table, Transparent. — This, as shown in the illus- 
 tration, consists of a square-bottomed bos, the tops of the sides of 
 which are inclined like those of a writing-desk. The back is open, 
 and, as the apparatus rests on the table, abuts against a window. 
 The window-shade is drawn down to meet the upper part of the 
 device, so that the liglit enters through the back of the latter. 
 
 A TKANSPAKENT TRACTNG-TABLE. 
 
 and the interior, being lined with white iiaper, is reflected up 
 through the inclined glass top ; the original drawing is laid upon 
 the glass, and a sheet of tissue-paper ruled off in squares is 
 placed above it. Being brilliantly illuminated from below, the 
 drawing would readily sliow through, and might be copied, square 
 by square, as belore described. 
 
178 PRACTICAL TECHXOLOGY. 
 
 SIMPLE GALVANIC BATTERIES AND ELECTRO- 
 PLATING RECIPES. 
 
 Battery Carbons. — Tliese can be readily cut witli a hand- 
 saw moistened in water. 
 
 Battery, Daniell's, Substitute for copper in. — Brighten sheets 
 of ordinary sheet-tin and plunge into a very weak copper-plating 
 solution, in connection witli a galvanic battery of very low quan- 
 tity. In 15 or 18 hours a tenacious film of copper will have been 
 deposited upon the tin, and the plate can then be bent in shape 
 suitable for the battery. 
 
 Battery, Galvanic, A cheap. — Mr. W. M. Symons proposes 
 a cheap but convenient galvanic battery : each of the zinc plates 
 js 2 in. square, and covered with fustian or other fabric, out- 
 side which thick copper wire is wound to form the other plate ; 
 the exciting liquid is weak chloride of zinc. Pairs of plates 
 thus made can be arranged in series to form a battery to give out 
 weak currents for a great length of time. 
 
 Battery, Galvanic, A simple. — Take a glass tumbler, and 
 place in the bottom a sheet of copper, having an insulated wire 
 attached and extending out of the tumbler. Cover the cop])er 
 with blue vitriol, and suspend a sheet of zinc near the top. Fill 
 the tumbler with water. Connect the zinc and copper together 
 for 48 hours, and the battery will be ready for use. 
 
 B.\ttery, Galv.\nic, Exciting liquid for. — Dissolve protosul- 
 phale of iron, 20 i)ts., by weight, in 'Sit pts. of water, stir in a 
 dilution of sulphuric acid (eijual parts of acid and water,) 7 pts., and 
 add 1 part nitric acid similarly diluted. This liquid has great 
 energy, and disengages no deleterious fumes. 
 
 B.\ttery Zincs, Amalgamation of. — The simjdest and quickest 
 method consists in immersing the zinc in a li(}uid comj)Osed of 
 nitrate of mercniry and hydrochloric acid. A few moments are 
 sufficient for the complete amalgamation of the zinc, however 
 soiled its surface may be. With a quart of this liquid, which 
 costs less than 50 cents, 150 zincs can be aiualgamated. The 
 liquid should be ])repared in this manner : Dissolve in warm 
 water 200 grains of mercury in 1000 grains of aqua regia (nitric 
 acid 1 part, liydrochloric acid ;j ])arts). When the mercury is 
 dissolved, add 1000 grains of hydrochloric acid. 
 
 Electro-Maonets, Softening. — Magnets or armatures for 
 electro-motors may be softened as follows : Heat the iron to an 
 even dull-red lieat all over ; and if the surface of the iron has 
 not V)een faced off in a machine, liglitly file it to remove the scale, 
 and then immerse it in common srjftsoap, allowing it to n-main 
 therein until it is <|uitr cold. Then reheat the magnet to an <'ven 
 red heat whose redness is ])arely ])erceptible, and bury it in pul- 
 verized lime, wherein it must also remain until <|uite cold, wljen 
 the metal will be found as soft as it is possible to make it, and 
 the blade of an ordinary penknife will cut it. At the second 
 heating, (lie iron will emit a light blue flame, showing the effect 
 
PRACTICAL TECHNOLOGY. l79 
 
 of the immersion in the softsoap. The capability of receiving 
 strong magnetic power may be, by this process, very much in- 
 creased. 
 
 Electro-Plated Paper or Cloth. — Make a solution of ni- 
 trate of silver, and add ammonia until the precipitate formed at 
 first is entirely dissolved. Place the paper or cloth for 1 or 3 
 hours in the liquid. After removing and drying, expose to a 
 current of hydrogen gas, by which the silver is reduced to a 
 metallic state, and the paper or fabric becomes so good a conduc- 
 tor of electricity, that it maybe electro-plated with copper, silver, 
 or gold in the usual manner. 
 
 Electro-Plating, Cleansing metals for. — Most articles are 
 rapidly cleaned by chemical means. The first of these is the re- 
 moval of grease by boiling in a solution of caustic soda, made by 
 boiling 2 lbs. of common washing-soda and ^ lb. cjuicklime in a 
 gallon of water ; after this they should be well brushed under 
 water. The further processes will depend upon the nature of the 
 objects. 
 
 1. Silver is washed iu dilute nitric acid, then dipped for a mo- 
 ment in strong nitric acid, and well washed. Care must betaken 
 that the water does not contain chlorine salts ; if the ordinary 
 supply does so, the first rinsing after acids must be made in wa- 
 ter J5repared for the purpose by removing the chlorine by adding 
 to it a few drops of nitrate of silver, and allowing the chloride to 
 settle. 
 
 2. Copper, brass, and German silver are washed in a pickle of 
 water 100 parts, oil of vitriol 100 parts, nitric acid (sp. gr. 1.3) 50 
 parts, hydrochloric acid 2 parts. Spots of verdigris should be 
 first removed by rubbing with a piece of wood dipped in hydro- 
 chloric acid ; they are then rinsed in water. 
 
 3. Britannia metal, pewter, tin, and lead can not be well clean- 
 ed in acids, but are to be well rubbed in a fresh solution of caus- 
 tic soda, and passed at once, without washing, into the depositing 
 solution, which must be alkaline. 
 
 4. Iron and steel are soaked in water containing 1 lb. oil of 
 vitriol to the gallon, with a little nitric and hydrochloric acids 
 added. Cast-iron requires a stronger solution, and careful rub- 
 bing with sand, etc., to remove scale and the carbon left by the 
 acids. It is an advantage at times to connect them to a piece of 
 zinc while cleaning. These metals should be cleaned just before 
 placing in the depositing cell ; and if they are placed in an alka- 
 line solution, they should be rinsed and dipped in a solution of 
 caustic soda, to remove all trace of acids. 
 
 5. Zinc may be cleaned like iron, with a dip into stronger acids 
 before the final washing. 
 
 6. Solder requires special care, as the acids used with the ob- 
 jects produce upon it an insoluble coating, and an obstinate resist- 
 ance to deposit is set up at the edge of the solder. The same 
 remark applies to soft -metal edgings and mounts. These should be 
 rubbed with a strong caustic-soda solution, rinsed, and then 
 treated as follows : Make a weak solution of nitrate of copper 
 by dissoh-ing copper in dilute nitric acid ; to a camel-hair 
 or other soft brush, tie 3 or 4 fine iron wires to form part of the 
 
180 PRACTICAL TECHNOLOGY. 
 
 brush ; dip this in the nitrate of copper, and draw over the solder, 
 taking care that some of the iron wires touch it ; a thin adherent 
 of copper will form, and upon this a good deposit will take place. 
 7. Old work for replating must have the silver and gold care- 
 fully removed ; if this is not done, there is apt to be a failure of 
 contact at the edges of the old coatings, which causes blisters 
 and stripping under the burnisher. The best mode of stripping 
 is wiih the scratch-brush, etc., but chemical means may be used. 
 Gold is dissolved by strong nitric acid, to which common salt is 
 gradually added ; it may be collected afterward by drying and 
 fusing with soda or potash. Silver is similarly dissolved by 
 strong sulphuric acid and crystals of saltpetre, and recovered by 
 diluting and precipitating with hydrochloric acid, then reducing 
 the chloride either by fusion with carbonate of soda, or by acid 
 and zinc cuttings. Copper can be removed from silver by boiling 
 with dilute hydrochloric acid, and tin and lead by a hot solution 
 of perchloride of iron. 
 
 Insulators, Rubber, Substitutes for.— Ivory and guaiacura 
 wood, which are both relatively good conductors, become nearly 
 non-conductive if stove-dried and saturated with certain oily and 
 resinous liquids, which close up the pores of the bodies in (jues- 
 lioii, and prevent moisture from penetrating within. Other kinds 
 of wood can be modified in the same manner. 
 
 Sawdust of bard wood, agglutinated with blood and submitted 
 to a considerable pressure, so as to mould it into a solid, tenacious 
 body, is a good insulator for voltaic currents. After remaining 
 six days in a damp cellar, it showed no galvanometric deviation. 
 
 Iron, Electro-plating with silver on. — The direct irciy : The ar- 
 ticle should first be rendered free from rust by rubbing with em- 
 ery-cloth, or by (lipping it into a pickle composed of sulphuric acid 
 2 ozs., hydnjciiloric acid 1 oz., water 1 gal. After the article has 
 remained some time in this pickle, it should be taken out and the 
 rust removed by a brush and wet sand. If the oxide can not be 
 easily clfaiicd off, it must be returned to the pickle. As soon as 
 the article is rendered bright, it is W'ashed in a warm solution of 
 soda, for the purpose of removing all grease. Lastly, it is well 
 rinsed in hot water, and immediately placed in the plating solu- 
 tion, which should contain only about onc^ fourth as much silver 
 as that usinl for plating copper and brass articles. The battery 
 power must al.so be weak. When the object receives a sliirht 
 coating, the process may Ix; carried on mort! rapidly by increasing 
 the battery j)Ower, and by placing the article in a much stronger 
 l)lating bath, using about 1 oz. silver in a gallon of solution. 
 The indirect method consists in first coating the iron with copper, 
 which insures success. C'o])per adheres firmly to iron, but silver 
 does nr)t ; hence rop])er acts the part of a go-lx'tween. After the 
 articli! has i)(-en cleaned, as above described, it is coated with 
 cojipcjr by placing it in a solution comiiostMl of (-arbonate of potas- 
 8a 4 OZ8., sulphate of copjjer 2 ozs., li(|uid ammonia about 2 oz., 
 cyanide; of i)otassinni (i ozs., water about 1 gal. 'i'lie sul])hate 
 of co|)per nniy be dL^^solved in warm rnin-wafer, iinil, when cold, 
 the carbonate of potassa and iiinnionia added : the ])recipilai(? 
 wlH!n formed is redjssolved. '{'he cyanide of potassium should 
 
PRACTICAL TECHNOLOGY. 181 
 
 now be added, until the bluish color disappears. Should any pre- 
 cipitate be found in the bottom of the vessel, the clear solution 
 may be poured off from it. The solution is worked culd, and with 
 modi rate battery power. Let the article remain in the bath 
 until a thin film of copper is deposited, then remove quickly, 
 rinse in hot water, and place in the silvering solution, where 
 the process may go on as rapidly as if plating a copper article. 
 
 Pewter, Electro-plating. — Take 1 ounce nitric acid, and drop 
 pieces of copper in it until effervescence ceases ; then add ^ ounce 
 water, and the solution is ready for use. Place a few drops of 
 the solution on the desired surface, and touch it with a piece of 
 steel, and there will be a beautiful film of copper deposited. The 
 application may be repeated if necessary, though once is general- 
 ly sufficient. The article must now be washed and immediately 
 be placed in the plating bath, when deposition will take place 
 with perfect ease. 
 
 Steel, Magnetization of.— If a properly-tempered steel needle be 
 introduced into a magnetizing bobbin connected with a battery of 
 constant current, battery and bobbin comprising the circuit, it ac- 
 quires a total determined magnetism at the end of a period which 
 appears not to exceed that of its introduction. On slowly with 
 drawing the needle, it is found to retain residual magnetism,"whicli , 
 together with the total magnetism, increases with each repeated 
 introduction until a limit is reached. The needle may be mag- 
 netized in the bobbin by three other methods : 1. EdaUishment : 
 Introduce the needle ; establish the current ; slowly withdraw 
 the needle. 2. Interruption : With a closed circuit introduce the 
 needle slowly ; break the current and withdraw the needle. .S. 
 Instantaneous charge : Introduce the needle ; establish and 
 break the current ; withdraw the needle. Kepetitions of any of 
 these three processes (all things being equal) insure an augmen- 
 tation of the needle's magnetic moment. The last method is the 
 best, but care must be taken to introduce the needle and current 
 always in the same position, so as not to reverse the poles. 
 
 USEFUL CHEMICAL RECIPES FOR DETECTION 
 OF ADULTERATIONS, FILTERING, INK-MAKING, 
 ETC. 
 
 Beer, To prevent, from turning sour while on draft. — A 
 slate cistern is made, having a wooden lid, fitting accurately, 
 floating on the surface of the liquid. The sides of the lid are be- 
 veled, so that a sharp edge is presented to the walls of the cistern, 
 and iilong this edge a strip of india-rubber is fastened, which 
 forms, with the bevel on the upper side, a V-shaped space, into 
 which wet sand is packed in order to keep the rubber in close 
 contact with the sides of the cistern, and so to exclude the air 
 from the same. A hole is formed in the lid, having a stuffing-box, 
 through which a pipe passes into the liquid, and the connection 
 
182 PRACTICAL TECHNOLOGY. 
 
 to the beer-engine is made in the usual way. The end of the pipe 
 in the liquid is closed, but perforations are made in the sides 
 about an inch therefrom : this prevents any sediment escaping 
 with the fluid. Atmosplieric pressure, acting on the lid, forces 
 it to descend as the liquid is removed from under it, and thus a 
 constant flow is obtained by means of the engine. By letting 
 the cistern into the ground, the temperature of the liquid will 
 remain nearly uniform the year round. 
 
 Beek, To clarify. — Take isinglass, finely shredded, 1 lb., sour 
 beer, cider, or vinegar 3 or 4 pints ; macerate together till the 
 isinglass swells, and add more of the sour liquid until a gallon 
 has been used. Strain and further dilute. A pound of good 
 isinglass should make 13 gallons finings, and 1-^ pints finings is 
 enough to clear a barrel of beer. 
 
 BisuiiPHiDE OF Carbon,To deodorize. — Distill with quicklime, 
 the two substances having been in contact for 24 hours. The 
 distillate is received in a flask partially filled with clean copper 
 turnings. The lime remaining in the retort is strongly colored. 
 
 Campiiok, To powder. — Take camphor 5 ozs., alcohol 5 fi. 
 drachms, glycerine 1 fl. drachm. Mix the glycerine with the al- 
 cohol, and triturate it with the camphor until reduced to a fine 
 powder. 
 
 Candles, Paraffine. — To dye beautiful red, i)urple, or violet 
 tints, use aniline colors. 
 
 Casks, Mouldy, To disinfect. — Wash first for about 5 minutes 
 with an alkaline solution of soda, and then soak for 1 or 2 days 
 with a liquor acidulated with hydrochloric acid. 
 
 CuLOROFORM, Purifying decom])osed. — Shake up the chloro- 
 form with a few fragments of caustic soda. 
 
 Dyeing Leatiiku Yellow. — Picric acid dyes leather a good 
 yellow, without any mordant ; it must be used in very dilute 
 solution, and not warmer than 70° Fahr. Aniline blue modifies 
 this color to a fine green. 
 
 Dyes, Testincj, for Adilteratiox. — Red dyes must neither 
 color soap-and- water nor linu'-wat(;r, nor must they themselves 
 become yellow or brown after boiling. This test shows the 
 presence or absence of Brazil-wood, arcliil, safflower, sandal- 
 wood, and the aniline colors. Yellow dyes must stand being 
 boiled with alcohol, water, and lime -watir. The most stable 
 yellow is maddei'-ycllow ; the least stable are aiuitto and tur- 
 meric ; fustic is rather better. Blue dyes must not color alcohol 
 reddish, nor must they decompose on boiling with hydrochloric 
 acid. Tlie best ])urph; colors are com])oscd of indigo and codii- 
 neal.or purpnrine. The forniiT test applies al.'^o to tlu-m. Orange 
 dyes must color luMtlier water nor alcohol on boiling ; green, 
 iieitlier alcohol nor hydrochloric acid. Brown dyes must not 
 io.'^e iheir color on standing with alcohol, or on boiling with wat(!r. 
 If black colors liave a basis of indigo, they turn greenish or blue 
 on Itoiling with so<liniii eurhonate ; if the dye l)e ])ure gall-nuts, 
 it turns brown. If tin; material changes to red on boiling with 
 liydrochloric acid, the coloring matter is logwood without a basis 
 
PRACTICAL TECHNOLOGY. 
 
 183 
 
 If it changes to blue, indigo is 
 
 A SIMPLE FILTER. 
 
 of indigo, and is not durable, 
 l^resent. 
 
 Filtering, Hot. — The apparatus consists of a tube of soft 
 sheet-lead, which can be wound around the funnel containing 
 the filter in the form of a spiral. One end of the tube passes 
 through a cork in the neck of a flask, in which water, or other 
 liquid of higher boiling-point, is boiled ; the other end dips into 
 a receiver, into which the condensed liquid flows. 
 
 Filter, A simple. — The engraving represents a very good 
 filtering apparatus. The best 
 material for the box would 
 be soapstone ; the next best 
 material, iron. Mott's cast- 
 iron tank-plates come of a con- 
 venient size — 18 X 18 inches 
 and 9 X 18 inches. These may 
 be galvanized or coated with 
 slate-paint. 
 
 Freezing-Powders. — (1) 
 Four pounds sulphate of soda, 
 2i pounds each of muriate of 
 ammonia and nitrate of pot- 
 ash ; when about to use, add 
 double the weight of all the 
 ingredients in water. (2) Equal parts of nitrate of potash and 
 muriate of ammonia ; when required for use, add more than dou- 
 ble the weight of water. (3) Nitrate of ammonia and water in 
 equal proportions. (4) Carbonate of soda and nitrate of am- 
 monia equal parts, and 1 equivalent of water. 
 
 Filters, To make charcoal. — One method consists in pulveriz- 
 ing animal charcoal until reduced to an impalpable powder. This 
 is mixed with a definite proportion of Norway tar and a com- 
 pound of other combustible substances. The combined materials 
 are then properly amalgamated with liquid j^itcli, and the whole 
 kneaded up into a homogeneous plastic mass which admits of 
 being moulded into slabs or blocks of any required dimensions 
 and shape. These blocks, having been allowed to dry and harden, 
 are subsequently carbonized by being subjected to a process of 
 incineration by heat ; and in this manner all the combustible 
 ingredients are burned out, leaving nothing behind but the 
 animal charcoal in the form of a block of charcoal, permeated 
 throughout by innumerable pores. 
 
 Gases, Drying. — Anhydrous phosphoric acid is the best sub- 
 gtauce known for this purpose. 
 
 Glycerine, Adulteration of, with sugar and dextrine. To detect, 
 — To 5 drops of glycerine add 100 to 120 drops of water, 0.4 to 0.6 
 grain of ammonium molybdate, 1 drop pure nitric acid, and boil 
 for a minute and a half. If any sugar or dextrine is present, the 
 mixture will assume a deep-blue color. 
 
 Glycerine, Purification of. — To purify glycerine which has 
 been for some time in use, add 10 lbs. iron-filings to every 100 
 lbs. of the impure liquid. Occasionally shake it and stir the 
 
184 PRACTICAL TECHNOLOGY. 
 
 iron. In the course of a few weeks, a black gelatinous mass will 
 collect on the bottom of the vessel, and the supernatant liquid 
 will become perfectly clear, and can be evaporated to remove any 
 excess of water that may have been added to it. 
 
 Glycerine, Testing. — When treated slowly with sulphuric 
 acid, it should not turn brown ; with nitric acid and nitrate of 
 silver, it should not become cloudy ; and vvheu rubbed between 
 the fingers it should not emit a fatty smell. 
 
 Hides, To preserve. — Carbolic acid is used in South-America 
 and Australia for this purpose. The immersion of hides for 24 
 hours in a two per cent solution of carbolic acid, and subsetjuent- 
 ly drying them, has been successfully substituted for the more 
 tedious and expensive process of salting. 
 
 Hydrocarbons, Classification of. — The classification usually 
 adopted by distillers is as follows : All above 88° of Baume's 
 hydrometer is called cliymogene, from 88° to 70° gasoline, from 
 70° to 60^ naphtha, from 60" to 50° benzine, from 50° to 35° kero- 
 sene, from 35° to 28° lubricating-oil. 
 
 Ink, Blue. — Prussian-blue 6 parts, oxalic acid 1. Mix with 
 water to a smooth paste. Dilute with rain-water, and add a 
 little gum-arabic to prevent spreading. 
 
 Ink, Copying, used without a press. — Coarsely-broken extract 
 of logwood 1 oz., carbonate of soda (crystallized) 1 drachm : heat in 
 a porcelain capsule with 8 ozs. distilled water until the solution 
 is of a deep-red color. Remove from fire and stir in glycerine 1 oz., 
 neutral chromate of potash dissolved in a little water 15 grains, 
 and a mucilaginous solution of 2 drachms finely-pulverized 
 gum-arabic. Kee})S well, never recjuires a press for copying, and 
 does not attack steel pens. The impression is taken on thin 
 moistened copying-paper, at the back of which is jilaced a sheet 
 of writing-paper. 
 
 Ink from Elderberries. — Bruise the berries, place them in 
 an earthen vessel, and keep in a warm place for 3 days. Press 
 out and filter. Add to 12^ ozs. of this filtered juice 1 oz. sulphate 
 of iron and the same quantity of pyroligneous acid. This ink is 
 violet at first, and afterward becomes black. 
 
 Ink, Indkliiu.k, for marking linen.— (1) Bichloride of copper, 8^ 
 grains, dissolved in distilled water, 30 grains ; then add common 
 salt, 10 grains, and liquid ammonia, iiA grains. A solution of 30 
 grains hydrochlorate of aniline in 20 grains distilled water is 
 thin added to 20 grains solution of gum-aral)ic, containing 2 pts. 
 water, 1 pt gum arable, and 10 grains glyetM-ine. Four jjurts of 
 the aniline solution tiius prei)ared are mixed with 1 part of the 
 copper solution. This ink can be used with a steel pen. it is 
 green at first, but becomes black in a ftnv days or by application 
 of liot iron. It is absolutely indelil)le, and the finest devices can 
 be written with it. It is bettiT to mix the two solutions only 
 just before using. (2) For very fiiu; linen, take a solution of 
 nitrate of silver, 4 jtts., in distilled water, 2-t ])ts. Adil li(|uid 
 aininonia until the precipitate formed is dissolved. Then a little 
 sap-green and indigo are ground together and mixed with a so- 
 lution of gum-arabic, 4 pts., and this is mixed with tlie nitrato 
 
PKACTICAI, TECHNOLOGY. 185 
 
 of silver solution. The whole is then diluted until it occupies 32 
 parts. It turns black as No. 1 does. 
 
 Ink, To restore dim. — Cover the letters with solution of ferro- 
 cyanide of potassium, with the addition of diluted mineral acid 
 (muriatic) ; upon the application of which the letters will change 
 to a deep-blue color. To prevent the color from spreading, the 
 ferrocyanide should be put on first, and the dilute acid added 
 ujDon it. 
 
 Inks, Aniline. — Violet ink is obtained by dissolving one part 
 of aniline violet-blue in 300 parts of water. This ink is quite 
 limpid, dries quickly, and gives a remarkably dark color. It is 
 necessary that new pens should be employed in using it, as the 
 smallest quantity of ordinary ink mixed with it causes its altera- 
 tion. Blue ink is made by dissolving 1 ])art of soluble Paris-blue 
 in 250 parts of boiling water ; red ink, by dissolving 1 part of soluble 
 fuchsiu in 200 parts boiling water. While ordinary inks are 
 decomposed by numerous substances, and notably by hydrochloric 
 acid, aniline inks are completely ineffaceable from the paper on 
 which they are used. They resist the action of acids, and even 
 of chlorine. 
 
 Inks, Sympathetic. — Yellows (1): Sulphate of copper and sal- 
 ammoniac, equal parts, dissolved in water ; (2) onion-juice ; both 
 visible on heating Black (1) : Weak infusion of galls. This is 
 turned black by weak solution of protosulphate of iron. (2) 
 Weak solution of protosulphate of iron. Turns blue when 
 moistened by weak solution of prussiate of potash, and black by 
 infusion of galls. Brown : Very weak solutions of nitric, sulphu- 
 ric, muriatic acids, common salt, or nitrate of potash. Visible on 
 heating. Green : Solution of nitromuriate of cobalt. Brought 
 out by heat ; fades when cool. Rose-red : Acetate of cobalt solu- 
 tion, with a small quantity of nitrate of potash. Acts as pre- 
 ceding. Solutions of nitrate of silver and terchloride of gold 
 become permanently dark when exposed to sunlight. 
 
 Ink, White, for colored paper. — 1 part muriatic acid, and 20 
 parts starch-water. Very dilute oxalic acid may also be used. 
 Write with a steel pen. 
 
 Ivory and Bones, Bleaching. — Spirit of turpentine is very 
 efficacious in removing the disagreeable odor and fatty emana- 
 tions of bones or ivory, while it leaves them beautifully bleach- 
 ed. The articles should be exposed in the fluid for 3 or 4 
 days in the sun, or a little longer if in the shade. They should 
 rest upon strips of zinc, so as to be a fraction of an inch above 
 the bottom of the glass vessel employed. The turpentine acts 
 as an oxidizing agent, and the product of the combustion is an 
 acid liquor which sinks to the bottom, and strongly attacks the 
 bones if they be allowed to touch it. The action of the turpen- 
 tine is not confined to bones and ivory, but extends to wood of 
 various varieties, especially beech, maple, elm, and cork. 
 
 Ivory, Imitation.— To liquid chloride of zinc of 50° to 60° 
 Baume, add 3 per cent of sal-ammoniac ; then add zinc- white until 
 the mass is of proper consistence. This cement may be run into 
 moulds, and when hard becomes as firm as marble. 
 
18G PRACTICAL TECHNOLOGY. 
 
 Light, brilliant white, To make a. — Fill a small vessel of 
 earthenware or metal with perfectly dry salpetre or niti'e, press 
 down a cavity into its surface, and in this cavity place a piece of 
 phosphorus ; ignite this, and the heat given off melts a sufficient 
 quantity of the nitre to evolve oxygen enough to combine with 
 the phosph(M'us, and the effect is to produce the most magnificent 
 white light which chemistry can afford. 
 
 Mica. — The best comes from th(3 Eastern States. New-York 
 mica is good. Canada mica is of several different shades, from 
 light brown to intensely black. 
 
 Oil, Cotton-Seed, Refining. — One hundred gallons of the crude 
 oil are placed in a tank, and 8 gallons of caustic potash-lye, of 
 45° Baume, are gradually added and well stirred for several 
 hours ; or the same quantity of oil is treated with about 6 gallons 
 of soda-lye of 25° or 30° Baume, and heated for an liour or more 
 to about 200° or 240° Fahr., under ])erpetual stirring, and left to 
 settle. The clear yellow oil is then .«e]iarated from the brown 
 soap stock, and this dark soap sediment is placed into bags, 
 where the remainder of tlie oil will drain off ; and the sediment 
 has a marketable value of 3 or 4 cents a i)c)und for soap-makers. 
 The potash-lye has to be made in iron pots, but tlu; oil and lye 
 may be mixed in wooden tanks. 
 
 Oils from Plants, odoriferous. Extraction of. — This can be 
 done by glycerine. The fiowers are intnxhiced into tlu^ liquid 
 and left for 3 weeks. The glycerine is then drained off, and 
 may be dissidved in all i)ri)porti()ns in alcohol or water to make 
 perfumed liquids or washes. 
 
 0[i,s, Liii{i{i('ATiNfi,T(^stingfor acids in. — Dissolve a crystallized 
 pie(;e of carbo.iatc! of soda al)out as large as a walnut in an (Mjual 
 i)ulk of water, and |)lace, the solution in a Hask with sonu; of tlie 
 oil. if, on settling after thorough agitation, a largi; quantity of 
 precipitate forms, tlu; oil should be rejected as impure. As oils 
 are often clarified and l)leached with acids, which injure the 
 metals on which they are usimI, this is an inii)ortant point to 
 know. 
 
 On,, Si'iCHM, To prevent gumuiiug. — It may he purified by agi- 
 tating 100 parts oil with 4 parts chloride of lime and 12 water; 
 a small (piantity of decoction of oak hark is alterward added to 
 remov(! all tnici-sof gelatinous matter which it retains, and tlu^ 
 mixture is left to settle. Tlu^ clear oil is afterward agitated 
 with a snuill i)orlion of sul|)huric acid, again clarified by subsi- 
 dence), and waslied to remove adhering sulphuric acid. The ad- 
 dition of mineral oils, as heavy kerosi-ne, has also tlie tendency 
 to prevent guMiniing, or at: least greatly to diniinisli it. 
 
 Oll,H,V()i,ATii-K, Explosion of. — A mixture of 2 ]iartH of perfectly 
 dry permangatiati! of potassium with 2 or 3 parts of concentrated 
 sulphuric; acid is a most powerful oxidizing agent, owing to the 
 sepiiratioii of permanganic acid and its immediatf! decomposition 
 with the liheratioi) of oxygen. Volatile oils are violenily affect- 
 ed l)y this mixture, if about 10 drops are pluced in a little disli 
 and then touched with a stout glass, rod previously dipped into 
 the mixture. 'I'he following produce exploBJons, often most vio- 
 
PKACTICAL TECHJ^"OLOGY. 187 
 
 lently : oils of thyme, mace, turpentine (rectified), spike, cinna- 
 mon, origanum, rue, cubebs, and lemon. The following oils are 
 simply inflamed, particularly if poured upon blotting-paper and 
 touched with the mixture, though under certain still unknown 
 circumstances explosion may occur : oils of rosemary, lavender, 
 cloves, rose, geranium, gaultheria, caraway, cajeput, bitter- 
 almond, and rectified petroleum. The following substances are 
 ignited without explosion : alcohol, ether, wood-spirit, benzole, 
 chlorelayl, sulphide of carbon, and cotton. Gun-cotton and gun- 
 powder are not ignited. 
 
 Petroleum, Test for illuminating. — Fill a tumbler full of 
 water at 110° Fahr. Stir in a tablespoonful of the oil to be tested, 
 and leave until the oil reaches about the same temperature. Pas^s 
 a lighted match over the oil as it fioats on the surface. If the oil 
 does not ignite, it can be safely used ; if it does, discard it, how- 
 ever cheap the price may be. Improved test proposed by Dr. Van 
 der Weyde : Fill a narrow test-tube with the petroleum to be 
 tested, close it with the finger, invert it, and plunge entirely in 
 water of some 140° Fahr. ; wait until the temperature has 
 descended to 110° ; if then any gas-bubbles are seen in the 
 closed upper part of the test-tube the oil contains dangerous in- 
 flammable vapors. As all vapors of petroleum are inflammable, 
 it is not necessary to ignite them ; the demonstration of their 
 presence in this way is sufficient to condemn such oil. 
 
 Raw Hide, To dissolve. — This can be done completely in water 
 heated under pressure. 
 
 Resins, Solubility of. — Copal, amber, dammar, colophony, 
 lac (or shellac), elemi, sandarac, mastic, and carnauba wax (a 
 resin) have been experimented upon. Amber, shellac, elemi, 
 sandarac, and mastic swell u^p and increase in bulk when heated ; 
 the others fuse quietly. Carnauba wax melts in boiling water, 
 colophony becomes pasty therein, while dammar, shellac, elemi, 
 and mastic agglutinate. Copal, amber, and sandarac do not 
 change in water. 
 
 Alcohol does not dissolve amber or dammar ; it agglutinates 
 copal, and partly dissolves elemi and carnauba wax ; while colo- 
 phony, shellac, sandarac, and mastic are readily soluble therein. 
 
 Ether does not dissolve amber and shellac ; it makes copals 
 swell, and partly but slowly dissolves carnauba wax ; it readily 
 dissolves dammar, coloi)hony, elemi, sandarac, and mastic. 
 
 Acetic acid does not dissolve amber and shellac ; it causes copal 
 to swell ; it somewhat acts upon carnauba wax, but not at all \ipon 
 any other of the resins above named. A hot solution of caustic 
 soda, of sp. gr. 1.074, readily dissolves shellac, with difficulty 
 colophony, and has no action upon the rest. In sulphide of car- 
 bon, amber and shellac are insoluble ; copal swells therein ; 
 elemi, sandarac, mastic, and carnauba wax are with difficulty 
 dissolved, while dammar and colophony are readily so. Oil of 
 turpentine has no action upon amber or shellac ; it causes copal 
 to swell, and readily dissolves dammar, colophony, elemi, san- 
 darac, carnauba, and very readily mastic. Sulphuric acid does 
 not dissolve carnauba wax ; it dissolves and colors all other 
 resins brown, except dammar, which becomes bright red. Nitric 
 
188 pHactical technology. 
 
 acid docs not act upon the resins, but covers carnauba wax 
 straw-vellow, elemi dirty yellow, and mastic and sandarac 
 bright" brown. Ammonia does not dissolve some of these resins, 
 but causes copal, sandarac, and mastic first to swell, afterward 
 dissolving them ; colophony is easily soluble therein. 
 
 EuBBEK, Solvents for— These are ether (free from alcohol), 
 chloroform, bisulphide of carbon, coal naphtha, and rectified oil of 
 turpentine. By long boiling in water, rubber softens, swells, and 
 becomes more soluble in its peculiar menstrua ; but when exposed 
 to the air, it speedily resumes its pristine consistence and volume. 
 Oil of turpentine dissolves caoutchouc only when the oil is very 
 pure and with the ap])licati()n of heat ; the ordinary oil of turpen- 
 tine of commerce cau.ses india-rubber to swell rather than to be- 
 come dissolved. In order to prevent the viscosity of the india- 
 rubber when evaporated from its solution, one part of caoutchouc 
 is worked up with two ])arts of turpentine into a thin paste, to 
 which is added + part of a hot conceatrated solution of sulphuret 
 of potassium in water ; the yellow liquid formed leaves the 
 caoutchouc perfectly elastic and without any viscosity. The solu- 
 tions of caoutchouc in coal-tar, naphtha, and benzoline are most 
 suited to unite i)ieces of caoutchouc, but the odor of the solvents 
 is perceptible f:r a long time. Sulphide of carbon is the best sol- 
 vent for caoutchouc. This solution, owing to the volatility of the 
 menstrum, soon dries, leaving the latter in its natural state. 
 When alcohol is mixed with sulphide of carbon, the latter does 
 not any longer dissolve the caoutchouc, but simply softens it. and 
 renders it capable of being more readily vulcanized. Alcohol 
 also precipitates solutions of caoutchouc. When caoutchouc is 
 treated with hot naphtha distilled from native petroleum or coal- 
 tar, it swells to 30 times its foriiicr bulk ; and if then tritu- 
 rated with a pestle and pressed through a sieve, it affonis a ho- 
 mogeneous varnish, the same that is used in preparing the patent 
 water i)roof cloth of Macintosh. Caoutchouc dissolves in the 
 fixed oils, such as linsecd-oil, but the varnish has not the ]>roper 
 ty of becoming concrete on exposure to thi' air. ('aout<^ho\ic melts 
 at a heat of about 2m' or 2(50 aft.-r it has been nudted ; it does 
 not solidity on cooling, but forms a sticky mass which does not 
 l)ecome solid even when exposed to the air for months. Owing to 
 this ])roj)erty, it furnishes a valuable material for the lubrication 
 of stop-cocks and joints intended to n-niain air tight and yet be 
 movable. 
 
 RlTHiiKU, To cut. — Dip the knife-blade in a ftolulion of caustic 
 potash. 
 
 ViNK(i.\K, Making, from alcohol (.Xrtiis's process). — Dissolve^ 
 oz. dry bichlorid.- of i)lalinuni in 5 lbs. of alcohol With this 
 moisten li lbs. of charcoal broken to the size id a hazel-nut. ll<-at 
 the charcoal in a covered criu-ible, and place it in the bottom of a 
 vinegar vat. This (anses the rai)id oxiiiation of tin; a'^oh'd. 
 Reheat the charcoal onc.t in 5 wiM-ks. 
 
THE FARM. 
 
 FARM BITILDINGS. 
 
 Beams, Fastening in walls. — The usual custom of building 
 the ends of floor-timbers into brick and stone walls is apt, in case 
 of fire, to throw over the walls ; and resting the timbers on cor- 
 bels interferes with the cornice-line below. By cutting the ends 
 of the timbers on a bevel and laying in the wall, as in the annex- 
 
 SETTING BEAMS IN WAllS. 
 
 ed diagram, the cornice-line will not be broken ; and, in case of 
 fire, the timbers will fall with little injury to the wall. 
 
 Blasting. — In small blasts, 1 lb. of powder will loosen about 
 4i tons of rock. In large blasts, 1 lb. of powder will loosen 2.} 
 tons. 50 or GO lbs. of powder inclosed in a bag and hung against 
 a barrier will demolish any ordinary structure. One man can 
 bore with a bit 1 in. in diameter, fnjm 50 to 60 in. per day of 10 
 hours in granite, or 300 to 400 in. per day in limestone. Two 
 strikers and a holder can bore with a bit 3 in. in diameter 10 ft. 
 per day in rock of medium hardness. 
 
 Bricks from Gas-Coal Ashes.— These are of remarkable 
 lightness, porosity, and dryness. Tlie ashes, after being taken 
 from the retorts, are spread on the surface of a clean floor ; they 
 are then finely pulverized, and 10 per cent of slaked lime, togeth- 
 er with a small proportion of water, is intimately stirred and in- 
 corporated with them. After a rest of 24 hours, the mixture is 
 made into bricks by the ordinary process. The bricks are imme- 
 
190 THE FARM. 
 
 diately transferred to the drying slit^ds, wliere a few days' expo- 
 sure renders them fit for use. 
 
 Brickwouk, Preserving. — To exclude dampness, use the fol- 
 lowing : f lb. mottled soap is dissolved in 1 gall, boiling water, 
 and the hot solution spread steadily with a flat brush over 
 the outer surface of the brickwork, care being taken that it 
 does not lather ; this is allowed to dry for twenty-four hours, 
 when a solution, formed of J lb. alum dissolved in 2 galls, 
 water, is applied in a similar manner over the coating of soap. 
 The soap and alum form an insoluble varnish, which the rain is 
 unable to penetrate, and this cause of dampness is thus said to 
 be effectually removed. The operation should be performed in 
 dry, settled weather. 
 
 Another method is to use 8 parts linseed oil and 1 part sulphur, 
 heated together to 278^, in an iron vessel. 
 
 Chimneys, Smoky, Causes of. — Want of sufficient height 
 in the flue. The outlet of the chimney being jihiced in an 
 exposed and cold situation, while the air with which the fire 
 is supplied is drawn from a warmer and more sheltered re- 
 gion. Excessive width in the flue, by which a large volume of 
 cold air is drawn in and allowed to lower the temperature of the 
 ascending column. Low temperature of the interior of the flue, 
 in comparison with that of the external air. Humidity of the 
 air. Too accurate fitting of the windows and door.s, and joints in 
 the flooring. Tlie draft of one Are injuring that of others in the 
 same house. A current caused by the heat of the fire circulating 
 in the room. A flue of insufficient size. A foul flue. Displace- 
 ment of masonry, or accumulation of mortar within the flue. 
 The sudden obstruction of the draft, by gusts of wind entering 
 the chimney-top. Increase of density of the air at the chimney- 
 top, duo to the eff(M-t of wind in chimneys rising from the eav(?s 
 of roofs. Drafts within the room which throw the smoke out of 
 the influence of the ascending chimney current. 
 
 Chimneys, Smoky, Preventing efl'ects of. — A screen or blower 
 of wire gauze, from ;j6 to 40 wires to tins inch, placed in front of 
 range or stove lires, will prevent, it is said, smoke coming into 
 the room when tlu^ cliimney fails to draw well. 
 
 CisTEHN, Building a. — One thing is essential, and is very ge- 
 nerally neglected. It is to have tlui water as it comes into tiie 
 cist(!rM conducted to tlie liottom. In this way, the water is en- 
 tirely changed when it rains. When the fresli water simply 
 pours in at tin; top, it immediatidy runs olT, and all tiu! nuiss of 
 stagnant water remains undisturb(Hl, and soon becx)mea impure. 
 
 ClsTKKN Fii-TER. — .\ wall of Soft luirned bricks is well adapt- 
 ed for tills i)urpos(!, wlien built up within the cist<!rn. 
 
 CoNCKKTE FoiJND.VTiONS, To build. — The concrete is c/mipos- 
 (fd of lime, sand, wiitcr, grave], and round or lirolcen stones. 
 A trench of l)oardH is first made, f)f the widtii of the desired foun- 
 dation. Fill tlu! tnmcli witli the concrete to the depth of a foot 
 or two, and let it stand until sullicitntly hard ; then add another 
 footof concrete, and so go on, ad<Hng concrete and raising trench- 
 boards as tlic Willi rlsrs. 
 
THE FARM. IPl 
 
 CoNCKETE Pavements. — The cheapest material for mixing 
 with gravel is coal-tar from gas-works. 
 
 Greenhouse, To build a cheap. — Mr. Peter Henderson says 
 the ordinary span-roof is best. The walls are 4 ft. high, formed 
 of locust or cedar posts. To the outside of these are nailed 
 boards — rough hemlock will do, if appearances are not consid- 
 ered. To the boards is tacked the ordinary tarred paper used by 
 roofers. Against the paper is again nailed the outer or weather 
 boarding. This makes really a better wall for greenhouse pur- 
 poses than an 8-inch one of brick, as we find that the extremes 
 of temperature of the greenhouse — inside at 50°, and perhaps 10° 
 below zero outside — very soon destroy an 8-inch solid brick wall, 
 particularly if exposed to the north or west. A wall of wood con- 
 structed as above will last for twenty years, and be as good a pro- 
 tection as one of 8-inch brick. The roof is formed by the ordina- 
 ry sashes, 6 ft. in length by 3 ft. in width, which can be bought 
 ready made. Heat with a flue not more than 60 and not less than 
 30 ft. in length ; if more, the flue would not heat it enough, and 
 if less it would be likely to get too much heat. About 50 ft. by 
 11 is, we think, the best size of a greenhouse to heat with a flue. 
 The flue should run all around the house — that is, it should start 
 along under one bench, cross the end, and return under the other 
 bench to the end where it begins, making the length of flue in a 
 greenhouse of 50 feet about 110 feet long. It should have a 
 " rise " in this length from the furnace of at least 18 in., to se- 
 cure a free draught. For the first 25 ft. of flue nearest the fur- 
 nace it should be built of brick, forming an air-space inside of 
 about 7 x 7 in. From this point (25 ft. from the fire) the flue 
 should be formed of the ordinary drain-pipe cement or terra-cot- 
 ta. The former is to be preferred, and that of 7 or 8 in. diame- 
 ter is best. The cost of a greenhouse thus built in the vicinity 
 of New-York, is about $6 per running foot — that is, one 50 ft. 
 long by 11 ft. wide costs $300. 
 
 Ice-House, To build an.—A house 12 ft. square by 8 or 9 ft. 
 high is large enough for a good-sized family. It may be a frame 
 building, entirely above the surface of the ground, and better if 
 supported on posts, elevated a few inches, to be certain of good 
 drainage. Build of joists, 3x3 in., with an outer boarding, hav- 
 ing inside another series of uprights, also boarded, from 6 to 10 
 in. removed from the outer shell, with a solid floor of plank, the 
 space between the two walls filled with tan, sawdust, straw or 
 chaff, and a roof of good pitch. A drain for water should be 
 made from the floor, and the space above the uprights, between a 
 loose flooring and the pitch of the roof, filled with straw, hay, or 
 some other dry, porous material. On the roof should be a venti- 
 lator, the top defended from rain or snow. The ice should be 
 packed in one solid mass, the sides not reaching the inner walls, 
 but allowing a space of from 6 to 12 in. all around. The top of 
 the ice should be covered with straw, and the door should be like 
 the sides of the building, or double doors should be made, one in 
 the outer and the other in the inner wall. Plant morning-glories 
 or any other climbing plant about the building, and train them 
 up over the roof, so that their foliage will serve as a protection 
 against the sun. 
 
19-2 THE FARM. 
 
 LiGHTNiNG-RODS, Valuable hints concerning. — Feather-beds 
 are not a protection frona lightning. The human body is a 
 better conductor of electricity than feather-beds or other objects 
 ordinarily contained in the apartments of dwellings, and there- 
 fore, when the lightning enters an apartment, the human body is 
 likely to form one in a chain of inductions, determining the path 
 of an electrical discharge, unless better conductors are in its vi- 
 cinity to divert this action. 
 
 The only place of absolute security in a thunder-storm is an iron 
 building ; or nest in safety is a building properly protected by 
 lightning-rods. 
 
 A copper rod of one inch in diameter, or an equal quantity of 
 copper under any other form, will resist the effect of any discharge 
 of lightning hitherto experienced. The copper rod is therefore 
 the safest and best material that can be used, but it is expensive. 
 Iron rods of one inch in diameter are very commonly used, and, 
 if pointed with solid copper and properly put up, are efficacious 
 in the great majority of cases. The particular form of the rod 
 makes no difference. It may be round or square, twisted or hol- 
 low, composed of one solid piece or made of wires twisted to- 
 gether. It is the quantity of metal contained in the cross-section 
 of the rod that is of value, not the form. 
 
 Lightning-rods are provided with sharp points to allow the ac- 
 cumulated negative fluid to pass off readily into the air and neu- 
 tralize the positive fluid of the thunder-cloud. 
 
 The object being to make so good a passage for the lightning 
 to the ground as to remove all danger of its leaping to some con- 
 ductor in tlie house, the greatest care must be taken not to have 
 any break in tlie conductivity. As it is inconvenient to manufac- 
 ture or tran.^port the rods in one piece, the different parts must be 
 in intimate connection when they are put up ; it is best to have 
 them soldered, and the joints protected from the air and moisture. 
 
 The point of the rod should be extended a little above the chim- 
 ney or highest part of tlie building, and should be fastened in 
 contact with the l)uilding by stajjles or cleats. Glass insulators 
 sliould not be emi)loyed. It nuikes no difference in conductivity 
 whether the rod is painted or not painted. 
 
 No building can be said to be properly rodded or protected 
 against lightning, unless the lower part of the rod or terminal 
 ui\der the ground is made quite extensive. The extremity of the 
 rod should connect with masses of good conducting materials, 
 such as old iron, or iron ore, or coke, or charcoal, laid in trenches, 
 or the rod itself should be elongated, sunk deep in the ground, 
 and curried a considerable distance from the building, and juit in 
 .•oiinection witli water, or moist earth if possible. Tlu' golden 
 riiit- for safety is : " Provide the largest possible area of conduct- 
 ing 8urfac(! for tlie terminal of the rod." 
 
 A lightning-rod which is not properly connected with the earth 
 is quite dangerous. The very common method of merely stick- 
 ing the lower end of the rod down into the dry earth near the 
 surfa<-eof the ground is bail, and endangers the building, because 
 dry earth is such ai)oor coiKluctor, and tlie amount of rod surface 
 in contact witli the earth is so small I'nder such conditions, a 
 portion of the electric current will be liktdy to find an easier path 
 
THE FAEM. 193 
 
 to the earth, through the building than through the rod ; and a 
 part of the electricity will therefore leave the rod, strike into the 
 building, and down in various directions into the earth, making 
 havoc as it goes. As a measure of prudence, house-owners should 
 look to the terminals of their lightning-rods, and place there a 
 considerable amount of the conducting materials above named. 
 
 It was supposed to have beeu established by Charles and Gay 
 Lussac that a liglitning-rod protected an area whose radius was 
 doulile the height of the rod extending above the building ; but 
 this rule is no longer reliable, by reason of the extensive use of 
 metals in the shape of pipes, etc., in the construction of the build- 
 ings of our day. 
 
 When electricity finds several paths to the ground, it will pre- 
 fer the best, it is true ; but some portion will also pass along the 
 poorer conductors If, therefore, any metallic substances lie 
 within the area supposed to be protected, they are in danger of 
 being struck. This is especially true where the lightning has a 
 chance to jump to the gas and water pipes of a building. It is a 
 good plan to connect these pipes with the lightning-rod ; if the 
 rod is struck, the electricity will then have an excellent path into 
 the ground, and will be rapidly diffused over the vast underground 
 network of pipes. The danger to the inmates of the house of 
 being struck from these pipes is less than that of receiving a 
 shock from the powerful induced currents liable to be developed 
 in them, if unconnected, during a thunder-storm. 
 
 The more rods on a building the better, especially if all are 
 connected with each other near their upper ends. 
 
 Finally, in the way of general advice, we would say: Connect 
 all your lightning-rods together, and also to your iron tank, and 
 water, gas. or other pipes, not by separate connections, but so that 
 there is some connection between all, which connection should be 
 as high up as possible. If you have a metal roof, connect all rods 
 with it. If the roof is not of metal, then connect your rods to- 
 gether by means of a good-sized conductor running along the 
 ridge of the roof. Bear in mind that, to carry off the heaviest 
 lightning-flash known, a copper rod one inch in diameter is not 
 considered too large ; and though of course such flashes are of 
 very rare occurrence, they may come. Hence the great value of 
 uniting your different rods high up. 
 
 Mortar, Good weatherproof. — 3 bushels clean sand, mingled 
 with I bushel good lime and i bushel cement, makes an excellent 
 mortar which is not liable to be dislodged by storms. 
 
 Mortar, To make. — The lime ought to be pure, completely 
 free from carbonic acid, and in the state of a very fine powder ; 
 the sand should be free from clay, partly in the state of fine sand 
 and partly gravel ; the water should be pure, and, if previously 
 saturated with lime, so much the better. The best proportions 
 are 3 parts fine sand, 4 parts coarse sand, 1 part quicklime recent- 
 ly slaked, and as little water as possible. There should always 
 be enough water added at first ; if water is added after slaking 
 has begun, it will be chilled and the mortar lumpy. The addition 
 of burnt bones improves mortar by giving it tenacity, and ren- 
 ders it less apt to crack in drying. 
 
194 THE FARM. 
 
 Oak Timber, Seasoning. — Oak loses about }; its weight in sea- 
 soning, and about ^ its weight in becoming perfectly dry. 
 
 Pavement, Farmyard. — Make a concrete of gravel or sand and 
 Portland cement ; or easier, of gravel, sand, coal-ashes, and coal- 
 tar. Dig away the earth for 5 in., lay a bottom of pebbles as 
 large as goose-eggs, ramming well down. Sweep off clean, and 
 pay the surface with hot coal-tar, thinly ; ]iut on a coat of small 
 er gravel previously dipped in hot tar, drained, and rolled in coal 
 ashes with an intermixture of gravel. Roll it down as compact- 
 ly as possible. Let the roller run slow, and let a boy follow it 
 with a hoe to scrape all adherent gravel. Next, put on a coat of 
 fine gravel or sand, coal-tar and some coal-ashes, to complete the 
 surface. Roll again. This will take some weeks to harden, but 
 will shed water, and eventually form a very firm surface. Do not 
 use too much tar, but only enough to make the ingredients cohere 
 under pressure. 
 
 R.\t-Pkoi)F Buildings. — The plan adopted in England is to 
 have slate fioors, sawed and planed to uniform sizes and thick- 
 ness. The walls are also covered with sawed or planed slates, 
 well jointed and secured to the wall or studding with screws, 
 wliich makes each room as secure against rats as an iron or stone 
 box would be. The slate used for the fioor is from 1 to 2 in. thick, 
 and that for the walls i in. thick. 
 
 Rat-Phook Frame Buildings. — Xail strips of board to the 
 sill between each flooring joist, on the inside, reaching to the un- 
 der side of the flooring planks or boards, and thereby covering the 
 shelf formed by the sill between tlie joists. The idea is to allow 
 the rats no place to stand upon while they are cutting through 
 the floor. 
 
 Roads, Corduroy, To build. — First lay all small poles or 
 brush transversely and across the road. Next take long trees — 
 the smallest ends being at least 10 inches diameter — and ])lace 
 them longitudinally across the poles, in two rows, 8 feet apart 
 from centre to centre, making the ends at the junction of each 
 ])iece lap each other at least 8 feet, breaking joint on either side, 
 and jjlacing upon these ends large logs of sullicient length to ex- 
 tend across the road, and 3 feet on each side of these stringers. 
 Cover the stringers with transverse; logs, 12 feet long from scarf 
 to scarf, and at least 10 inches in diamettir at the smallest end, 
 fitted close together on tlu^ straight portions ; the logs alternated 
 with a large and small end, and on the outer side of curves, all 
 the large <;nds, wliieh will assist in the curvatur<>of the road and 
 thr- gravity of the vehi<;les. Next, adze off" the centre ridges of 
 thest; logs to a face of about 5 inches, for a width of 9 feet in the 
 (■(!ntre of the roadway, and cover this 9 f«'et with gravel, to fill in 
 between the; logs, and giv(; a smooth surface. A good plan is to 
 lay on the top of the road thus formed poles of 5 or inches in 
 diameter, si)ilied down on each sidt^ of the track, every 10 f(;et, 
 with oak i>ins, to jireveiit, in frosty weaiher, the lateral sliding 
 of wagons. 
 
 RuoKiN<i, Pasteboard ami asphalt — This material is most 
 suitable for fl:il roofs, having a fall of l.J inches to 4^ inches per 
 
THE FARM. 19,-, 
 
 running foot. It may, however, also be used for roofs liavinjr .a 
 greater fall, the expense being in this case somewhat larger tlian 
 ior flat roofs, as the laying on is more difficult. Cover the roof 
 first with dry boards, f incli to 1 inch thick, and not above 6 inch- 
 es broad ; it more than ihe last-named width, or if not suffi- 
 ciently dry, the boards ought to be split once before being laid on, 
 in order to keep them from warping, and every board should be 
 fastened with three nails at least on each of the rafters. The 
 boards do not require to be rabbeted ; only those ends of the 
 boards which form the eaves, by extending beyond tbe wall need 
 to be joined in the said manner. In case of boards | inch thick 
 being applied, the rafters f^hould not be moie than 2 feet from 
 each other, as the boards may be too elastic and not strong 
 enough to support the weight of the workmen, while the ronf 
 will not be perfectly substantial. 
 
 The roofing may be done either from gable to gable, or from 
 the eaves to the foot-ridge, the fir.-t roll being laid with a bend 
 of 1 inch beyond the roof, and fastened with the flat-headed iron 
 wire nails supplied for that purpose. The second roll is laid li 
 inches over the first, and so on till the roof is covered. The joints 
 and heads of the nails are then coated witli asphalt mastic, and 
 the seams thus coated are strewed with dry sand. The whole 
 roof is then coated with the mastic, and covered with sand. This 
 coating, which is only to be effected in dry weather, renders the 
 roof perfectly water-tight, and it can then, if desired, be painted 
 or whitewasbed. A hundredweight of mastic covers a surface of 
 65 square yards. This process is in use in Copenhagen, Den- 
 mark, and the roof weighs about ^ the weight of a tiled roof, and 
 is substantial, resisting alike the influenceof water, fire, heat, and 
 cold. 
 
 Roofing, Portland cement and tar. — The inclination of the 
 frameworkr of the roof (which must have an even surface) should 
 be at the rate of from + to | inch per foot. The rafters or joists 
 should not be more than 2 feet 3 inches apart, S) as to give suffi 
 cient strength. As the rafters rest on the side walls, a compara- 
 tively small quantity of timber is required. Boards of 1 inch or 
 IJ inch thick are fastened or nailed on the rafters, and should be 
 dovetailed. These are then covered with a layer of sand i or i. 
 inch thick, in order to produce an even surface. Strong brown 
 paper, in continuous rolls, and as broad as possible, is then laid 
 upon it, so that each length overlaps the other by about 4 inches. 
 When the whole or a large part has thus been covered with pa- 
 per, the mixture is put into a caldron, in the proportion of tar 100 
 pounds to Portland cement 180 pounds. Care must be taken to 
 heat the tar gently, and to mix the cement with it gradually, in 
 order to prevent its boiling over. This mixture of tar and ce- 
 ment mtist then be laid on as hot as possible on the paper with a 
 tar-brush. The next layer of paper is then laid upon it, and 
 smoothed with a light wooden roller. In this way the whole 
 roof must be covered. In order to break the joints of the paper, 
 begin the second layer with half the breadth, and proceed as be- 
 fore. The third and fourth layers are laid in like manner, with 
 alternate layers of cement and" brown paper The last layer must 
 be carefully covered with cement, and then strewn with sifted 
 
196 THE FARM. 
 
 ash.es to the thickness of i inch. Next to the gutter is a board 
 covered with zinc, and projecting about 3 inches. It should be 
 laid on after the second layer has been completed, so as to be co- 
 vered by the third and fourth. If there are any chimneys pro • 
 jecting through the roof, they should be surrounded with zinc 
 immediately after the first layer has been finished. 
 
 Roofing Zinc. — Permit perfect freedom to the sheets. Confine 
 them nowhere, and separate lengths of guttering, and any other 
 portions of a roof requiring to be made in long jneces, as much as 
 possible. Eaves-gutters should be made in short lengths, bent in 
 the direction of the way in which the sheet has been rolled and 
 soldered, the solder being put between the sheets, and one sheet 
 lapping over the other. Nor must they be screwed to the rafters, 
 as this is a practice which occasions a constant failure in the 
 joints of the iron eaves-gutters. Wherever a down-pipe conies, 
 there should be a stopped end in the gutter ; and the gutter 
 should not be continued longer than possible in one place. Where 
 it is laid behind a parapet, a separate piece of flashing will dis- 
 connect it wholly from the sheeting on the roof. For guttering, 
 the gauge used should be increased in proportion to length ; 
 there should be a proper substance in all cases. Oak boarding 
 will spoil the zinc, and the fir boarding should be dry — tlie 
 boards with an ajjerture of about ^ inch between each. If they 
 are damp, as much oxidation will take place on the under side of 
 the zinc as on top of it. From experiment, it appears that the 
 oxidation proceeds for about four years, gradually diminishing 
 after the first three months, when it hardens into a protecting 
 coat of a dark gray color, preserving the metal beneath from fur- 
 ther d£!terioration. A sheet of zincexjiosed to the atmosphere for 
 a series of years loses little or nothing of its weight or thick- 
 ness, and its surface remains hard and polished as enamel. 
 
 Shingles, To prevent decay of. — Put into a lar^e'tub 1 bar- 
 rel of wood-ashes lye, 5 pounds white vitriol, 5 pounds alum, and 
 as mucli salt as will di.ssolve in the mixture. Make the litpior 
 quite warm, and put in as many shingles at a time as it will co- 
 ver. When one batch of shingles is well soaked, remove and 
 put in another. Tiien lay the shingles in the usual manner. 
 With the li(juor that is left, mix enough lime to make white- 
 wasii, and color witii lampblack, oclire, or Spanisli l)rown. Ap- 
 l)ly to the roof with a brush or old broom. This wash may be 
 renewed from time to time. 
 
 Shinoi.es, Painting. — Lay low-priced shingles — say from f2.7o 
 to $4 ]H'r tiiousand — and i)aint {\u-m witli a coat of tar and 
 asplialtum — say one barnd coal-tar, costing ^;J ; ten ))Ounds of 
 asphailum at JJ cents, 'AO cents ; ten pounds ground slate, at 1 
 cent, 10 cents ; two gallons dead oil at 25 cents, 50 cents, which 
 should \)t; added alter Dk- otlier has been wetted and tiioroughly 
 mixed, 'i'liis mixture \^ as good as any tiling tluit can be put on 
 to sliingles, as it will tliorouglily iteep llie, water out ; and, if 
 dry, they will not rot under the lap, nor will the nails rust. 
 
 SiiATKS, Rooking, Selection of. — Dark purple and green slates 
 are tlic; best for roofing ; others are liable to fade unequally, and 
 produwi a disagreeahle appearance. 
 
THE FARM. 197 
 
 Sled-Body, To build a transverse. — Make tke sills out of 
 l-incli or f-inch boards, with oross-pieces of the same thickness 
 bolted between the sills, which are double. You can make these 
 very light and limber. Now put on your side-boards with a bolt 
 down through the rave and sill, which will make it very 
 stiff, and can be made very light, and with all the strength 
 possible. 
 
 Smoke-House, Cheap and good. — For 50 hams, make dimen- 
 sions 7x8 feet. Dig all the ground out to below the frost line, 
 and fill up to the surface with small stones. On this lay a brick 
 floor with lime mortar. Walls of brick, 8 inches thick by 7 feet 
 high, and a door on one side, 2 feet wide. Door of wood, lined 
 within with sheet-iron. For the top, put on joists, 2x4, set up 
 edgewise, and 8^ inches from centre to centre, covered with brick 
 and with a heavy coat of mortar. Build a small chimney over 
 the centre, arching it over and covering it with a single roof in 
 the usual way. An arch should be built on the outside, with a 
 small iron door, similar to a stove-door, to shut it up. Make a 
 hole in the arch through the wall of the house, and put an iron 
 grate over it. The arch is much raore convenient to put the fire 
 in, than to build the fire inside the house, and the chimney 
 causes a good draught through the latter. Burn good corn-cobs 
 or hickory wood. This house should cost about $20. 
 
 Stables, Building. — Bricks, built in hollow walls, are better 
 than any other material. Commence with a stone foundation — 
 the bottom course of which is broader than the stone-work above 
 it — laid in half cement mortar up to the grade line, and then build 
 the brick wall upon that, filling in all the space inclosed by the 
 walls with concrete up to the line of the top of the water-table. 
 Then pave with stones, firmly bedded to form a floor. On the 
 outside, there should be a stone water-table, 8 or 10 inches high, 
 projecting 1 or 2 inches outside of the main walls above, and 
 having the upper surface of the projection beveled off to shed the 
 water. Just above the water- table, it is well to have a course of 
 slate built in the full thickness of the walls, which will prevent 
 any dampness rising up into them from the ground by capillary 
 attraction. Above the water-table, the walls should be built up 
 with a smooth face, and with close, neatly struck joints inside as 
 well as out, so as to present a clean, even surface, which should 
 always be kept painted or washed with a lime or cement wash. 
 Above the wall-plate, the space should be filled in to the under 
 side of the root-boards. The ceilings over the main story should 
 be lathed and plastered ; partly for the sake of the neat appear- 
 ance, partly to keep away cobwebs which infest exposed beams, 
 and partly to prevent foul air rising from the room below, and 
 tainting the hay-loft. The doors and windows inside should be 
 trimmed with architraves, even if the latter be merely strips of 
 the cheapest stuff. It may be desirable to fur out and lath and 
 plaster the walls of a stable ; but if this is to be done, it is better 
 to wainscot with wood up to the height of, say 5 feet, and to fill 
 in the space between the walls and the wainscot, as high as prac- 
 ticable, with broken glass and mortar, and then to lath and plas- 
 ter from the wainscot up to the ceiling. A wooden stable, too. 
 
198 THE FAKM. 
 
 may witli advantage be treated in the same way, but the space 
 behind the wainscot being wider, may be packed with bricks and 
 mortar, and made solid in that way. 
 
 Timber, Strength of. — The strongest side is that which in its 
 natural position faced the north. 
 
 Timber, To test the soundness of. — Apply the ear to the mid- 
 dle of one of the ends, while another person strikes upon the op- 
 posite extremity. If the wood is sound and of good quality, tlie 
 blow is very distinctly heard, however long the beam may be. If 
 the wood is disaggregated by decay or otherwise, the sound will 
 be for the most part destroyed. 
 
 Trough, To make a tight. — Joint up the plank, and then, with 
 a wide punch, set down a groove about ^^ in. deep the whole 
 length ; then take off two or three shavings more, and put the 
 trqugh together. When the wet gets into that joint the grt)ove 
 swells out again just the thickness it was at first, and of course 
 two or three shavings thicker than the plank, and so closes all 
 up tight. Wood can also be ornamented by punching down 
 carefully in patterns, planing ofE a little, and then wetting ; the 
 parts punched down show in relief above the planed surface, and 
 make quite a puzzle. 
 
 Water-Closet, To put up a. — The engraving represents 
 sectional views of the water-closet in the upper floor of a 
 two-story house. A A is the level of the surface of the ground at 
 the back court and of the kitchen floor. B is a 6-inch vitrified 
 fire-clay siphon-trap, with an open iron grating, C, at its top, 
 which grating may be hinged. D is 4 inch soil-pipe fnmi the 
 water-closet ; it is here sliown coming down inside the wall ; 
 in other cases it may be carried down the outside. One advan- 
 tage of snch pijies being carried down the inside is that they are 
 more likely to be protected from frost. F is a ^-inch or 2-inch 
 load pipe for ventilating the soil pipe. In this case, it is carried 
 througli the wall ; in other cases it may be carried up through 
 the roof, (i is tlie water-closet trunk, made of iron, it being a 
 pan water-closet which is here shown. H is a finch h-ad pipe, 
 carried through the wall, and put in to ventilate the trunk, or 
 tliat sjjace between the wattT in the pan, I, or basin, J, and tlie 
 water in the siplKm-traj), K. This J-incli ventilating i)ipe, H, is 
 a very iini)ortant one, and its use ought to be th<^ rule in ])lace 
 of the «'Xcei)tion, as is at i)r<-scnt the case. It works as follows : 
 NN'lien the handle of the wati-r-closet is lifted, then any foul air 
 lying in the trunk, in place of coming out into the apartment, is 
 pent outside with a rush tlintugh this ]>il)e, 11 ; besides, being oj)en 
 to the air, it tends to prevent tlie ac<-uinulatinn of such foul air 
 in the trunk. 
 
 In order to kei-p the outer oritices of the i)ii)es, F and H, al- 
 ways o|)en, it is a good plan to solder on one or two i)ieces of 
 copper wire across tlieni. J is the water-closet basin, and the two 
 small circles shown, underutatli K K.are the india-rubber i)ipeB. 
 A li-inch zinc ventilating pipe may be carried up tlirough the 
 roof to vr-niilate the space or inclosure in which the water-closet 
 is situated. A gas-l)racket placed right below if will help, when 
 lighted, to cautfc an upward current. The enqjly space at N is 
 
TUE FAKM. 
 
 199 
 
 BUILDING ■WATER-CLOSETS. 
 
 supposed to be the water-closet window. O is the surface of the 
 floor of the upper flat. No gas can accumulate in the soil-pipe, 
 for the pressure of the atmosphere on the surface of the open 
 grating, C, tends to send a current of fresh air through the soil- 
 pipe and out at the ventilating pipe, F. 
 
 Water-Gate, a good. — This is an excell-nt device for fencing 
 purposes over small streams. A gate, sliding in upright ways at 
 the ends, like an old turnpike gate, has attached to the bottom 
 board (a scantling is better, as not so likely to be broken in hisfh 
 water) crutches which rest upon empty b irrels or casks. The up- 
 rights at the ends of the gate are provided with friction-rollers, 
 so that the jjate slides up and down easily in th * ways. Two or 
 three casks will generally support the weioht of the gate, so that 
 it descends nearly to the surface of, but does not enter, the water. 
 A gate thus constructed will rise and fall with the stream, and 
 is not liable to be washed away at high water. 
 
 Whiteavash, for outside work. — Take quicklime, i bushel ; 
 slake, and add coiiinion salt, 1 pound : sulphate of zinc, i 
 pound ; sweet milk. 1 ii:allon. Dissolve salt and zinc before add- 
 ing, and mix tin- wlmli' to [iroper consistence with water. 
 
2QQ THE FAUAt. 
 
 Wooden Buildings, To frame. — Particular attention should 
 be paid to biiuliug the top of the walls well together. This is 
 accomplished by framing the wall-plate all around the house, 
 and spiking the ceiling joists down on the same ; then heriing- 
 bone, bridging these joists in as many rows as are necessary to 
 make a thoroughly stifE brace for the whole. The roof (no mat- 
 ter whL^her Gothic or Mansard) can not exercise any bad influ- 
 ence in pushing out the walls, when this system is adopted. 
 
 Wood To season and prevent warping.— Strip off bark, and 
 bury about one foot deep in the spring, leaving in the ground for 
 six months, and you will find no difficulty. This was the only 
 wav by which the sapadillo or mountain mahogany in the Sierra 
 NeVada could be seasoned, it being one of the hardest and most 
 brittle kinds of wood known. 
 
 Windmill, To build a. — Windmills can be either horizontal 
 or vertical, but the latter are almost exclusively employed. In 
 the vertical windmill, the shaft is inclined to the horizon at an 
 an"-le of from 5' to 15% when the wheel is placed at the top of a 
 tower ; so that the wheel will clear the sides of the building, 
 and allow space for the action of the wind. If the wheel is 
 supported by a post, the shaft may be horizontal. The connec 
 tion of the "shaft with the pump or other mechanism maybe 
 made either with gearing or by means of a crank and connecting 
 rod. The shaft must be free to swing around in any direction, 
 BO that the wheel can always face the wind. It is moved, in the 
 case of small windmills, by tlie use of a weather-van.: on tlie 
 end of the shaft ojjposite to the wheel. With large windmills 
 supported on towers, the top of the tower is generally arranged 
 so that it can be rotated, and a small auxiliary wind-wheel, con- 
 nected by gearing, moves it into the proper position as the direc- 
 tion of the wind changes. The wheel of a windmill may be 
 covered with cloth, or with slats of wood or metal, the cover in 
 either case; being technically known as the sail. 
 
 Make the sail of a series of joined slats, that present a close 
 surface to wind of tlui ordinary velocity, and open, thereby de- 
 creasing the surface, as the velocity of the wind increases. The 
 best velocity for a windmill is such that its i)friphiry moves 
 about 2? tinies as fast as the wind. Thus, if the wind is moving 
 at the rate of 20 feet a second, the tips of tlie sails sliould move 
 at the rate of rti fe<'t a second, so that, if the wheel were 13 feet 
 in diameter, it should make about 8:5 revolutions a minute. Of 
 course, if the velocity of the wind varies greatly, it will be 
 impossible to keej) the speed constant, so that windmills are not 
 ordinarily well suited for work nHpiiring steady motion ; altlmngh 
 they answer very well for nioviuij jiumps, if an intermittent 
 supply of p(»wer is not a serious obstach-. in some sections, 
 liowever, tlic i.revailing winds are (|uit.- steady, and in such 
 nisi'S windmills ran Ix- iipplifd with advantage to grist-mills 
 and f)th<'r useful work. The force and veicicity of tin- wind can 
 only be determined by experiment, but the results of previous 
 experimenters may be useful : 
 

 
 THE FARM. 
 
 201 
 
 Velocity 
 
 of wind. 
 
 
 
 
 
 Perpendicular 
 force, in pounds 
 
 
 In feet per 
 
 In miles 
 
 Common expressions of 
 
 second. 
 
 per hour. 
 
 per square foot. 
 
 the force of the wind. 
 
 10 
 
 6.82 
 
 0.33 
 
 Gentle pleasant wind. 
 
 20 
 
 13.64 
 
 0.91 
 
 Brisk gale. 
 
 30 
 
 20.56 
 
 2.04 
 
 Very brisk. 
 
 40 
 
 27.27 
 
 3.92 
 
 High wind. 
 
 50 
 
 34.09 
 
 6.25 
 
 Very liigli. 
 
 60 
 
 40.91 
 
 9.25 
 
 Very high. 
 
 70 
 
 47.73 
 
 12.75 
 
 A storm. 
 
 80 
 
 54.55 
 
 16.34 
 
 A storm. 
 
 90 
 
 61.36 
 
 20.74) 
 25.28 1 
 
 
 100 
 
 68.18 
 
 A great storm. 
 
 110 
 
 75.02 
 
 30.89) 
 
 
 120 
 
 81.84 
 
 36.75 
 
 A hurricane. 
 
 130 
 
 88.65 
 
 43.26 
 
 A hurricane. 
 
 140 
 
 95.47 
 
 50.32 
 
 A violent hurricane. 
 
 150 
 
 102.29 
 
 57.56 
 
 A violent hurricane. 
 
 In the accompanying figure is shown one of the four sails of a 
 windmill, it having been found that four sails of proper propor- 
 tion produce the best effect. The 
 piece P B is called the whip of the 
 sail ; C D, E F, G H, etc., the bars 
 of the sail. The bars are inclined 
 to the plane of revolution at differ- 
 ent angles, the angle made by any 
 part of the sail with this plane be- 
 ing called the weather of the sail. 
 Making the distances A O, N L, L I, 
 etc., •each equal to -^ of the diame- 
 ter of the wheel, the best values for 
 the angle of weather are as follows: 
 
 For N 0-18° 
 For L M— 19° 
 For J K— 18° 
 
 For G H— 16° 
 For E F— 12i° 
 For C D— 7° 
 
 The sail stretched over these bars 
 will be a warped surface, some- 
 what resembling the blade of a 
 screw-propeller. The part B D 0, 
 called the leading sail, is triangular, 
 and B D is T5 of the diameter of the 
 wheel, B C being tV. ^^^^ ^ ^' "i^ o^ 
 the diameter. The main body of 
 the sail, B C N O, is commonly rect- 
 angular. A windmill of the best 
 proportions, running under the most 
 favorable circumstances, utilizes 
 about -fi^^ of the energy of the 
 wind that acts on an area equal to a circle having the same 
 diameter as the wheel. It would not be -advisable to count 
 on realizing more than half this power in general practice ; and 
 on this assumption, we have the following empirical rule for 
 
 BtlTLDINO A WINUMELL. 
 
202 THE FARM. 
 
 determining the diameter of a wheel to give a certain amount 
 of power with an assiuneJ velocity of the wind : 
 
 Divide the required horse-power by the cube of the velocity 
 of the wind in feet per second ; take the square root of the 
 quotient and multiply it by the number 2024.8. The product 
 will be the required diameter in feet. Example : A windmill is 
 to be erected in a locality where the general velocity of the wind 
 is about 20 feet per second. It is to be attached to a pump, the 
 work re()uired of it being to raise 1000 gallons of water per 
 hour through a height of 20 feet 1000 United States gallons of 
 water weigh about 8320 pounds, and, taking into effect the re- 
 sistance of ihe pump, the power required will be about f, of a 
 horse-power, or 0.167 horse-power. Dividing this by 8000, the 
 cube of tlie velocity of the wind, extracting the square root, and 
 multiplying by 2024.8, we obtain S)^ ft. as the required diameter of 
 the wheel, deferring to the figure, we find that, in this case, 
 C N is 3 feet 10|- inches, B D, 7| inches, and B C, ll;,^^ inches. 
 The velocity of the tips of the sales should be 52 feet per second, 
 or the wheel should make about 108 revolutions a minute. 
 
 THE DAIRY. 
 
 Btttru, Philadelphia. — The pans containing milk to the 
 depth of ;5 inches are set in flowing water, so as to be maintained 
 at a temperature of about 58° Fahr. After siaudmg 34 liours, the 
 milk is skimmed, and the cream ])ut in deep vessels of a capacity 
 of about 12 gallons. It is kept at a temperature of 58' to 59' until 
 it ac(|uiri's a slightly acid taste, wlien it goes to the diurn. The 
 churn is a barrel rtivolving on a journal in each head, and is 
 driven by horse-power. The churning occupies about an hour ; 
 atid after tlie butti^rmilk is drawn off, cold water is added and a 
 few turns given to the churn. The wiiter is then drawn off. This 
 is rep(nited until the water as it is drawn otf is nearly free from 
 milkiness. TIk; butter is worked with butter-workt^rs, a damp- 
 ened cloth mcianwliile being pressed upon it to absorb the 
 moisture and free it of buttermilk. Tlie cloth is frequently 
 di])ped in cold water, and wrung dry during the jjrocess of 
 wi))ing the butler. It is next salted at the rate of 1 ounce salt 
 to ;{ pounds butter, thoroughly and evenly ineorp )rated by means 
 of a butter- worker. It is then removed to ;i table, where it is 
 weighi'd out and put into pound prints. After this, it goes into 
 large tin trays, and is set in the water to harden, remaining 
 until next niorniiig, when it is wra|)j)ed in damp cloths ancl 
 placed upon shi'lves, oui- abovtMinother, iu tin lined cedar tubs, 
 with ice in the compartments at the ends; and thiui it go(^B 
 immi'diately to market. A I'liiladelphia Itutler di^aler says that, 
 for tlm l»eHt butter, 'tlie cows ure fi'd on wliite clover and early 
 mown meadow hay, cut fine; and mixed in with corn meal and 
 wiieaten sliorts. No roots are fed, except carrots. 
 
THE FARM. 203 
 
 Chttrning Milk, Temperature for. — 60° Fahr. 
 
 Cream-Gauge. — In a can 20 in. deep and 8 in. in diameter, cut 
 a slot a few inches long. In this slot, insert a strip of glass, in 
 grooves, and cement with white lead. Graduate the tin next to 
 the glass. Set the milk in the can, and allow the cream to rise. 
 The percentage may be seen on the glass and noted by the 
 scale. 
 
 Cream, White specks in. — These are caused by too much acid 
 in the cream. Cream should never stand in a room where the 
 milk is set, but should be put into a cool place if you would 
 avoid specks. 
 
 Cows, Care of. — Milk coming from ill-nourished, half- fed cows, 
 having no surplus of food beyond minimum requirements of na- 
 ture, is injurious, and may be a source of disease. Cows deprived 
 of an abundance of good water, ventilation, and exercise, secrete 
 impure and dangerous milk, which may be loaded with gases, 
 animalculse and fever-germs. The milk from old, debilitated 
 cows fed on grains or overstimulating food, is also imperfect and 
 unhealthy to a variable degree. The nervous condition of thb 
 cow at the time of milking determines the purity of the milk. 
 If this is neglected, the milk is an active source of disease, and 
 is positively dangerous and fatal. 
 
 Cow-Stables, Ventilation of. — Lay the floor of the stable upon 
 a solid bed of earth and yravel, with a fall of 6 in. in 13 ft. from 
 the stanchions, with the same ratio of descent, to a point for outlet 
 of liquids. Make a platform raised 6 in. for the cows to stand or 
 lie upon. The floor and platform plank should be bedded in 
 water-lime mortar, so that there shall be no soaking down nor 
 hiding-place for stale urine to deposit and generate venomous 
 odors. 
 
 Milk, Poisonous sour. — Sour milk, after protracted exposure 
 to the sun, develops a poisonous quality, sufficient to cause dis- 
 ease and death to pigs fed thereon. 
 
 Milk, Setting. — Place the pans in cold water, which will pro- 
 tect the milk from the acid until the cream has time to rise. 
 For cream to rise readily on milk, set in cold water ; the atmo- 
 • sphere in the room should be warmer than the water. There 
 will as much cream rise on milk set in cold water in one hour 
 as there will on milk not set in water in 24 hours. 
 
 Milk, Tainted. — Never allow dead animals to decay about a 
 pasture, or any where near a barn or other localities inhabited 
 by the milch-cows. The carrion odor is sure to affect the milk. 
 
 Milk, Testing for cream. — A simple method of determining 
 the quantity of cream in any sample of milk consists in agitating 
 the milk ina graduated glass tube with its bulk of ether for 4 
 or 5 minutes. Add alcohol in volume equal to that of the milk, 
 and shake for 5 minutes. Place the tube vertically and allow it 
 to rest lor a brief period, when the oily matter will rise to the 
 surface so that its amount may be read off on the scale and the 
 percentage easily computed. 
 
 Milk, To insure good. — The following questions Mr. X. A. 
 
204 THE FARM. 
 
 Willard, a well-known dairy authority, recommends to be writ- 
 ten out and posted about the dairy : " Do your cows feed in 
 8wam}3s and on boggy lands '? Have you good, sweet running 
 water convenient for stock, and is it abundant and permanent in 
 hot, dry weather? Have you shade-trees in your pasture, or 
 do you think that cows make better milk while lying down to 
 rest in discomfort in the hoi sun? Do you use dogs and stones 
 to hurry the cows from pasture at milking time, thus overheat- 
 ing their blood and bruising their udders ? Do you cleanse the 
 udders of cows before milking by washing their teats with their 
 own milk, and practice further economy by allowing their drip- 
 pings to go into the milk-pail ? Do you enjoin your milkers to 
 wash their hands thoroughly before silting down to milk ? When 
 a cow makes a misstej) while being milked, do you allow your 
 milkers to kick her with heavy boots, or to pound her over the 
 back and sides with a heavy stool ? Is the air about your ' milk- 
 barn' or milk-house reeking with the foul emanations of the 
 pig-sty, the manure-heap, or other pestiferous odors ?" 
 
 Milk, To prevent souring by tluinder-storms. — A fire started 
 in the dairy is an excellent preventive. This should be done 
 even in the hottest weather. The object is to remove the damp, 
 moist, heavy air, which is injurious to the milk. 
 
 Milk, To remove taste of turni])S in. — Give the cow no turnips 
 for two or three hours before milking. It is better to feed only 
 the centre of the turnip, cutting ofE the top and bottom. A 
 tablespoonfiil of nitn^ dissolved in as much water as it will take 
 to a gallon of milk, placed in the pail before milking, is said to 
 remove the taste of the vegetable. 
 
 FARM ITTNTS AND RECIPES, 
 
 Bee Moths, To kill. — Bee moths can easily be killed in large 
 numbers l)y setting a pan of grease, in which is a floating ignited 
 wick,n(^arth(! hives after dark. The moths will fly into the light 
 and fall into the grease. 
 
 Bones, Reducing. — Place them in a larg(! kettle tilled with 
 ashes, and about one peck of lime to a barrel of bones. Cover 
 with water and Imii. In 24 hours all the hones, with the excep- 
 tion, perhHi)S, of the hard shinlxmes, will heconie so much soft 
 encd as to i)e easily ])uiveri'/ed by hand. They will not be in 
 particles of bone, but in a pasty condition, and in an excellent 
 form to mix with muck, loam, or ashi-s. Hy boiling the shin- 
 hones 10 or 12 liours longer, they will also become soft. 
 
 Hones. Value of. as a (ertili/,<T.— 100 Ihs. of dry bone-dust 
 
 add to the soil as i h organic animal matter as ;!00 lbs. of 
 
 Mood or flesh, and al.soai the same time • their weight of inorganic 
 matter- lime, magnc'^ia, common salt, soda, and i)hos|>lioric acid. 
 Superphosphate of lime, commonly nr^ed liy farmers, is simply 
 
THE FARM. 205 
 
 bones treated witli ^ their weight sulphuric acid and an equal 
 quantity of water. 
 
 Carbonic Acid Gas, Removing from wells, cisterns, etc. — (1.) 
 A bellows with a rubber hose reaching near the bottom will soon 
 blow out the gas. (2 ) Let down a large bucket, draw up and 
 empty tlie gas as if it were water. (3.) Pour down water ; do this 
 when a person falls to the bottom from inhaling the gas. (4.) 
 Let down an umbrella spread, and pull up quickly several times 
 in succession. 
 
 Caterpillars, Exterminating. — Orchard or tent caterpillars 
 leave their rings of eggs on the young twigs. If these are cut off 
 with a clipping pole, it will prevent in every instance a large 
 nest of caterpillars, and be much more easily done than after the 
 latter have grown. 
 
 Caterpillars, Remedy for. — A solution (1 part in 500) of sul- 
 phide of potassium, sprinkled on the tree by means of a hand-sy- 
 ringe, is extensively used in France. 
 
 Celery, Propagation of. —A deep trench should first be dug, 
 at the bottom of which a layer of sticks of wood, say 6 in. thick, 
 should be placed a drain-pipe being placed endwise upon one or 
 both ends of the Jayer. The sticks should be then covered with 
 about a foot of ricli mouxd, wherein the plants should be set in a 
 row, and about 5 in. apart. The plants should be well watered, 
 the water being supplied through the drain-pipes, so that, pass- 
 ing through the layer of sticks, which serves as a conduit, the wa- 
 ter is supplied to the roots of the plants. In earthing up, care 
 should be exercised to close the stems of the plant well together 
 with the hand, so that no mould can get between them. The 
 earthing process should be performed sufficiently frequently to 
 keep the mould nearly level with the leaves of the outside stems. 
 If these directions are carefully observed, the plant may be grown 
 at least 4 ft. in length, and this without impairing the flavor. 
 
 Charcoal, Effect of, on flowers. — All red flowers are 
 greatly benefited by covering the earth in their pots with about 
 an inch of pulverized charcoal. The colors (both i-ed and violet) 
 are rendered extremely brilliant. Yellow flowers are not affected 
 in any way by charcoal. 
 
 Chickens, To fatten. — The best food for this purpose is Indian 
 meal and milk. 
 
 Chinch-Bugs, To destroy. — Put old pieces of rag or carpet in 
 the crotches of the trees attacked. When the worms spin, as they 
 will, in the rags, throw the latter in scalding water. The bugs 
 can thus be killed by wholesale. 
 
 Cider Barrels, To clean. — Pour in lime-water, and then in- 
 sert a trace-chain through the bung-hole, remembering to fasten 
 a strong cord on the chain so as to pull it out again. Shake 
 the barrel until all the mould inside is rubbed off. Rinse with wa- 
 ter, and finally pour in a little whisky. 
 
 Cider Casks, To prepare.— Cider should never be put into new 
 casks without previously scalding them with water containing 
 salt, or with water in which apple-pomace has been boiled. Beer- 
 
206 THE FARM. 
 
 casks slioiild never be used for cider, nor cider-casks for beer. 
 Wine and brandy casks will keep cider well, if the tartar adher- 
 ing to their sides is first carefully scraped oft and the casks be 
 well scalded. Burning a little sulphur in a cask will effectually 
 remove must. 
 
 Cider from apple-parings. — The parings of a bushel of apples 
 will yield 1 qt. of cider by the aid of the hand-press. 
 
 Cider-Making, Hints for. — 1. No- good cider can be made from 
 unripe fruit. The nearer to perfect ripeness the apples, the bet- 
 ter the cider. 2. No rotten apples, nor bitter leaves, nor stems, 
 nor filth of any kind should be ground for cider. 3. Two presses 
 are really necessary for each mill, so that the pomace can be ex- 
 posed to the air in the one, while it is being pressed in the other, 
 and thus acquire a deeper color. 4. New oak barrels, or those in 
 which whisky or alcohol has been kept, are the best. 5. If more 
 color and richer body are desired, a quart or two of boiled cider 
 to each barrel will impart them. 
 
 CiDEK, Purifying. — Cider may be purified by isinglass, about 
 1 oz. of the latter to the gallon. Dissolve in warm water, stir 
 gently into the cider, let it settle, and draw off the liquor. 
 
 Cider, To preserve sweet for years. — Put it up in air-tight cans, 
 after the manner of fruit. Rack it off the dregs, and can before 
 fermentation sets in. 
 
 Coal- Ashes as a fertilizer. — Mix them with a small propor- 
 tion of well-rotted horse-manure, sifting the ashes first, and you 
 will have an excellent fertilizer. 
 
 CoRN-CoBS, Utilization of. — Save the corn-cobs for kindlings, es- 
 pecially if wood is not going to be plentiful next winter. To pre- 
 pare them, melt togetlier 6U parts resin and 40 parts tar. Dip in 
 the cobs, and dry on sheet-metal heated to about the temperature 
 of boiling water. 
 
 Doos, Bed for. — The best is newly made deal shavings. They 
 will clean the dog as well as water, and will drive away fleas. 
 
 Dust, Road, Value of. — During a dry season, every country 
 resident should secure several barrels of road-dust. Tliose who 
 keep poultry may secure by its use a valuable fertilizer, nearly as 
 strong as guano, with none of its disagreeable odor. Place an 
 inch or two of roiul-dust in tlu! bottom of a barrel; tiuMi, as the 
 poultry liousc is ri'giilarly cleaned, deposit a layer an inch thick 
 of the cleanings, and so on, alternately layers of each till the bar- 
 rel is full. The thinner each layer is, the more perfect will be 
 the intermixture of the ingredients. If the soil of which the 
 road-dust is made is clayey, tlu^ layers of eacli may be of equal 
 thickuf^SH ; if sandy, th(! dust slioiiM be at least twice as tliick as 
 tli(! layer of drop|)ings. Old Ijarnds of any kind may be used for 
 this |)nrpose, but if previously soaked witli crude; petroleum or 
 coated with gas-tar, tlu^y will last many years. If the contents 
 are |K)iin(ied on a floor into fine powder befont applying, the; fer- 
 tilizer may be sown from a drill. Ifoad-diist is one of the most, 
 perfect deodorizers of vaults — converting their contents also into 
 rich manure. I'lace a l)arrel or b«>x of it in the closet, with a 
 
THE FARM. 207 
 
 small dipper, and throw down a pint into the vault each time it 
 is occupied, and there will be no offensive odor whatever. This 
 is simpler, cheaper, and better than a water-closet, and never 
 freezes or gets out of order. Mixing the road-dust with equal 
 bulk of coal-ashes is an improvement, making the fertilizer more 
 friable. 
 
 Fertilizer, A cheap. — This consists of sulphate of ammonia, 
 60 lbs. ; nitrate of soda, 40 lbs. ; ground bone, 250 lbs. ; plaster, 
 250 lbs. ; salt, ^ bushel ; wood ashes, 3 bushels ; stable manure, 
 20 bushels. Apply the above amount to six acres. Labor in pre- 
 paring included, it costs about $15. It is said to give as good 
 results as most of the commercial fertilizers costing $50 per ton. 
 
 Fish-Net, To preserve from decay. — Steep in melted paraffine. 
 
 Fowls, Fattening. — It is said that charcoal will fatten fowls, 
 and at the same time give the meat improved tenderness and 
 flavor. Pulverize and mix with the food. A turkey requires 
 about a gill a day. 
 
 Fruit, To preserve. — Fruit is kept in Russia by beincp packed 
 in creosotized lime. Tlie lime is slaked in water in which a little 
 creosote has been dissolved, and is allowed to fall to powder. 
 The latter is spread over the bottom of a deal box, to about one 
 inch in thickness. A sheet of paper is laid above, and then the 
 fruit. Over the fruit is another sheet of paper, then more lime, 
 and so on, until the box is full, when a little finely powdered 
 charcoal is packed in the corners, and the lid tightly closed. 
 Fruit thus inclosed will, it is said, remain good for a year. 
 
 Fallen Leaves, To utilize. — These should be carefully gath- 
 ered, as they are excellent to mix with hot-bed material. They 
 do not heat so rapidly as stable-manure, and in this have an ad- 
 vantage, as tempering the violence makes manure last longer 
 and maintain a more regular heat. They are excellent material 
 to put round cold frames to protect half-hardy plants. A board 
 is put up to the height of the frame boards, and about a foot or 
 more from them, and the leaves filled in between. If the plants 
 are somewhat tender, the bottom of the frajnes may be filled in a 
 few feet with the leaves. Fallen leaves, after having been two 
 or three years decaying, make admirable stuff for potting plants 
 and for flowers in general. 
 
 Grafts, Cutting and storing. — There is no better time to cut 
 grafts, than at the commencement of winter. lu cutting and 
 packing them away, let them be labeled. For this purpose they 
 should be tied up in bunches, not over 2 or 3 inches in diameter, 
 with 3 bands around each bunch — at the ends and middle. The 
 names may be written on a strip of pine-board or lath, ^ in. 
 wide, j-ij in. thick, and nearly as long as the scions. This, if 
 tied up with the bunch, will keep the same secure. For conveni- 
 ence in quickly determining the name, there should be another 
 strip of lath, sharp at one end, and with the name distinctly 
 written on the other, thrnst into the bundle with the name pro- 
 jecting from it. If these bunches or bundles are now placed on 
 end in a box, with plenty of damp pioss between them and over 
 the top, they will keep in a cellar in good condition, and anvsort 
 
208 THE FARM 
 
 may be selected, and withdrawn without disturbing the rest, by 
 reading the projecting label. It is needful, however, to keep an 
 occasional eye to them, to see that the proper degree of moisture 
 is maintained — which should be just enough to keep them from 
 shriveling, and no more. 
 
 Gkapes, To ripen. — In the Rhine district, grape-vines are kept 
 low and as near the soil as possible, so that the heat of the sun 
 may be reflected back upon them from the ground ; and the 
 ripening is thus carried on through the night by the heat radiated 
 from the earth. 
 
 Gr.vsshoppers, To utilize. — The grasshoppers, desiccated and 
 ground, are useful as a fertilizer ; but in this prepared condition, 
 they form an excellent food for all insect-feeding birds. There is 
 no better food for all young domestic fowls. Containing silicic 
 acid in a soluble state, they seem specially adapted for young 
 birds, promoting the growth of feathers. 
 
 fxRASsiNf; A Sr-OPE. — A steep* slope may be grassed over with- 
 out sodding by first smoothing the surface and then mixing a 
 tough paste or mortar of clay, loam, and horse-manure, with suffi- 
 cient water. The grass seed, which should be a mixture of Ken- 
 tucky blue grass and white clover, should be thickly but evenly 
 scattered upon the moist surface of this plaster as it is spread 
 upon the bank. Tiie plaster should be at least one or two inches 
 thick, and a thin layer should be laid over the seed. The surface 
 should be k(;pt moist, and a light dressing of some active ferti- 
 lizer would help the growth. In a few weeks the growing grass 
 should be cut, and should be kept short at ail times until a tliick 
 sod is formed. 
 
 (jiliAN'O, Handling. — Many cases of iioisoiiiug hiive occurred by 
 contact of guano with wounds. It should be handled with gloved 
 hands. 
 
 Gr.wo, Home-made. — Make a compound of 1 bushel ashes, 2 
 l)U8he8 fowl-tnanure, 1^- bushels jjlastcr, and 4 bushels muck. 
 Spread the muck on the barn-Hoor and dump tlie fowl-manure on 
 top of it. Pulverize the latter with the spade, and mix in the 
 otlicr ingredients. Moisten the heap with water, or, better, with 
 urine, l)ffore planting. Deposit alxtut a handful in each hill of 
 corn, potatoi's, or beans, mixing it with tin; soil before putting in 
 the seed. 
 
 IIakness, Cleaning. — Unbuckle all the i)arts and wash clean 
 with soft water, .soap, and a brush. A little tur])entine or benzine 
 will take off imy gummy substance which the soaj) fails to re- 
 move 'I'heu warm tiie leather, and, as soon as dry on the sur- 
 face, apply the oil with a paint-brush or a swab. Neat's-foot oil 
 is the bi;8t.. Hang up thi! harness in a wiirm place to dry, but do 
 not let it burn. 
 
 H MfNK-^-;, Oiliu!,''. — (live on« .)r two coats of lampblack and 
 castor-oil warmed sulIiciiMitly to make it peiietiate the stock 
 rea<lily. Then spongc! the harnesH with 2 (jts. warm soap-suds ; 
 when dry, rub over a mixture of oil and tallow, e(|ual parts, with 
 enough Prussian blue to give color. When well rubbed in, this 
 coiMpoiiiid leuves a smooth, (dean surface. 
 
THE FARM. 209 
 
 Harness, Working- team. — Do not use martingales on working 
 teams. See that the hames are buckled tight enough at the top 
 t(; bring the draft-iron near the centre of the collar. If too low, 
 it not only interferes witli the action of the shoulder, but giTes 
 the collar an uneven bearing. 
 
 Hay, Spontaneous combustion of. — Hay, when piled damp and 
 in too large masses, ferments and turns dark. In decomposing, 
 sufficient heat is developed to be insupjjortable when the hand is 
 thrust into the mass, and vapors begin to be emitted. When the 
 water is almost entirely evaporated, the decomposition continues, 
 and the hay becomes carbonized little by little ; and then the 
 charred portion, like peat — peat-cinders mixed with charcoal, sul- 
 phurous pyrites and lignite, etc. — becomes a kind of pyrophorus, 
 by virtue of its great porosity and of the large quantity of mat- 
 ter exposed to high oxidation. Under the influence of air in 
 large amount, this charcoal becomes concentrated on the surface 
 to such a degree that the mass reaches a temperature which re- 
 sults in its bursting into flames. The preventives for this danger 
 are care that the hay in the lofts is kept perfectly dry, that it is 
 well stacked, and that it is stored in small heaps rather than in 
 large masses. 
 
 Hay, To estimate the weight of. — Allow 1 cwt. of hay to the 
 cubic yard. 
 
 Horse, Power of. — The greatest amount an average horse can 
 pull in a horizontal line will raise a weight of 900 lbs. ; but he 
 can only do this momentarily ; in continued exertion, probably 
 half this amount is the limit. 
 
 Horses, Bedding for. — Sawdust serves this purpose well. 
 
 Horses, Buying, Hints for. — Examine the eyes in the stable, 
 then in the light ; if they are in any degree defective, reject. Exa- 
 mine the teeth to determine the age. Examine the poll or crown of 
 the head, and the witliers, or top of the shoulders, as the former 
 is the seat of poll evil, and the latter that of fistula. Examine 
 the front feet ; and if the frog has fallen, or settled down be- 
 tween the heels of the shoes, and the heels are contracted, reject 
 him, as he, if not already lame, is liable to become so at any 
 moment. Next observe the knees and ankles of the horse you 
 desire to purchase, and, if cocked, you may be sure that it is the 
 result of the displacement of the internal organs of' the foot, a 
 consequence of neglect of the form of the foot, and injudicious 
 shoeing. Exauine for interfering, from the ankle to the knees, 
 and if it proves that he cuts the knee, or the leg between the knee 
 and the ankle, or the latter badly, reject. " Speedy cuts" of the 
 knee and leg are most serious in their effects. 5lany trotting 
 horses, which would be of great value were it not for this single 
 defect, are by it rendered valueless. (.'arefuUy examine the hoofs 
 for cracks, as jockeys have acquired great skill in concealing 
 cracks in the hoofs. If cracks are observable in any degree, re- 
 ject. Also both look and feel for ringbones, which are callosities 
 on the bones of the pastern near the foot ; if apparent, reject. 
 Examine the hind feet for the same defects of the foot and 
 ankle that we have named in connection with the front feet. 
 Then proceed to the hock, which is the seat of curb, and both 
 
210 THE FAKM. 
 
 bone and blood spavins. The former is ft bony enlargement of 
 tlie posterior and lower poi'tion of the hock-joint ; the second a 
 bony excrescence on the lower, inner, and ratlu-r anterior portion 
 of the hock ; and the last is a soft enlargement of the synovial 
 membrane on the inner and upper portion of the hock. They are 
 either of them sufficient reason for rejecting. See that the horse 
 stands with the front feet well under him, and observe both the 
 heels of the ft-et and shoes to see if he " forges" or overreaches ; 
 and in case he does, and the toes of the front feet are low. the 
 heels high, and the heels of the front shoes a good thickness, 
 and the toes of the hind feet are of no proper length, reject him ; 
 for if he .still overreaches with his feet in the condition described, 
 lie is incurable. If he props out both front feet, or points them 
 alternately, reject. In testing the driving qualities, take the reins 
 while on the ground, invite the owner to get in the vehicle first, 
 then drive yourself. Avoid the display or the use of the whip ; 
 and if he has not sufficient spirit to exhibit his best speed without 
 it, reject. Should he drive satisfactorily without, it will then 
 be proper to test his amiability and the extent of his training in 
 the use of the whip. Thoroughly te.st his walking qualities first, 
 as that gait is more important in the horse of all work than great 
 trotting speed. The value of ahorse, safe for all purposes with- 
 out blinds, is greatly enhanced thereby. Purchase of the breeder 
 of the horse if practicable ; the reasons are obvious. 
 
 Houses, Common-sense treatment for. — (1) All horses must 
 not be fed in the same proportions, without due regard to their 
 ages, constitutions, and work. (3) Never use bad hay because it is 
 ch(!ap ; there is no nourishment in it. (3) Damaged corn brings 
 on inflannnation of the bowels and skin diseases. (4) Cliaii'is 
 better for old horses than hay, because they can chew and digest 
 it better. (5) Mix chaft" with corn or beans. (U) There is not 
 sutlicient nutritive body in either hay or grass alone to support a 
 horse under hard work ; in such case the food should chiefly be 
 oats. (7) For a .saddle or a coach horse, half a jieck of sound 
 oats and 18 lbs. of good hay is sufficient ; if tlie hay is not good, 
 add a (juarter of a peck more oats. (8) Hack feeding is wasteful ; 
 feed with chopped hay from a nuinger. (9) Sprinkle the hay 
 with water that has salt dissolved in it, becau.se it is jtleasing to 
 tlie aiiiinai's taste and more easily digested. A teaspooiiful of 
 salt in a l)ucket of water is sutlicient. (lO) Oats should be 
 bruised for an old horse, but not for a young one. (11) Cut grass 
 should always be given in sjjring to horses that can not be turned 
 out into the fields ; it is very cool and refreshing. (12) Water 
 horses from a pond or stream, rather tiian from a si)ring or well, 
 because' tlie water from the latter is generally hard and <'o]d, while 
 the former is soft and comparatively warm. 'I'lui liorse prefers 
 soft muddy water to liard water, though never so dear. (13) A 
 lior.'if! should liave at least a pailful of water morning and even- 
 ing, or (still better) four lialf pailfuls at four several times in 
 the day. because this assuages his thirst without bloiiting him. 
 He sbould not be made to work directly after a full draft of 
 water. (M) ]>o not allow a liorse to have warm water to drink, 
 since, if he lias to drink cold water after becoming accustomed to 
 
THE FARM. 211 
 
 warm, it will give him colic. (15) Do not work a horse when 
 he refuses food after drinking ; he is thoroughly fagged out. 
 
 Horses, Dead, To utilize. — Drag the body to some out-of-the- 
 way part of the farm and sprinkle quicklime over it. Then cover 
 with about twenty-five wagon-loads of muck or sods. In a year 
 an excellent manure-heap will be at your disposal. Smaller ani- 
 mals may be similarly utilized. 
 
 Horses, Scratches on. — These may be cured by washing the 
 legs in warm, strong soap-suds, and then in beef brine. 
 
 Horses, To keep flies from. — Make an infusion of 3 hand- 
 fuls of walnut leaves in 3 qts. of cold water. Let this stand 
 over night and boil for a quarter of an hour in the morning. 
 When cold, rub it over the ears, neck, and other irritable parts 
 of the animal, with a moist sponge. 
 
 Horses, Wounds on. — If suppuration is inevitable, use car- 
 bolic acid combined with glycerine or linseed-oil in the propor- 
 tion of 1 to 20. It may be applied night and morning with a 
 feather. The wound must be kept clean, and, in the case of 
 backs and shoulders, all pressure removed by small pads of 
 curled horse-hair, sewed on the harness above and below the sore. 
 
 Ice, Compressed. — Thin ice from ponds, or small pieces left 
 after cutting blocks from larger bodies of water, may be stored 
 in a profitable manner, and at the same time its preservation in- 
 sured, by compressing it into solid blocks by means of any simple 
 press. In localities where ice is not attainable, snow might 
 easily be treated in the same way. 
 
 Ice, To keep. — Select a shady spot, on the north side, if possible, 
 of a clump of trees. Throw up a circular mound, some 12 in. in 
 height and at least 15 ft. in diameter, flattening the summit care- 
 fully, and leaving a trench around the eminence, 2 ft. in width 
 and 18 in. in depth. In gathering the ice, there is no necessity of 
 cutting into uniform shape or of seeking large pieces. Fill up 
 the carts with any kind of fragments, transport them to the 
 mound, and dump them on a platform made of a few planks. 
 Ram the surface of the mound hard and firm, cover with sawdust, 
 and then place the first layer of ice, which should previously be 
 cracked into small pieces, for which purpose the men should be 
 provided with wooden mallets. As each layer is put on the stack, 
 the ice should be thoroughly pounded, both above and at the sides, 
 so as to form a huge block of ice, the shape of which will be 
 slightly conical. 
 
 When the stack is completed, it will require two coverings of 
 straw, one lying upon the ice and the other supported on a wooden 
 framework about 18 in. outside the first covering. 
 
 The layer of straw next the ice must be well beaten and flat- 
 tened down upon it, and when this is done, be 12 in. in thickness. 
 The framework, upon which a similar thickness of straw is placed, 
 may be formed by inserting stout larch or other poles of a suitable 
 length round the base in a slanting direction, so that they can be 
 readily brought together at the top, and securely fastened with 
 stout cord. From six to eight of these will, when joined together 
 by means of strips of wood fixed about 13 in. apart, aflEord ample 
 
212 THE FARM. 
 
 support for tlie second covering of the straw. Tliis must be put 
 on nicelj, so as to prevent the possibility of the rain's penetrating 
 to the inner covering. By this arrangement there will be a body 
 of air, which is one of the most effectual non-conductors known, 
 between the two coverings of straw. To effect a change of the 
 inclosed air, when rendered needful by its becoming charged with 
 the moisture arising from the melted ice, a piece of iron or earth- 
 enware piping a few inches in diameter should be fixed near the 
 apex, one end being just above the straw, and the other end 
 reaching into the inclosed space. The pipe can be readily opened 
 or stopped up, as may appear necessary, but as a rule it will suf- 
 fice to open the pipe once a week, and allow it to remain open 
 for about two hours. This should be done early in the morning, 
 as the air is then much cooler than during the day or in the even- 
 ing. 
 
 In removing ice from the stack, the early morning should be 
 taken advantage of, because of the waste which must naturally 
 ensue from a rush of warm air at midday. That removed can be 
 placed in a cellar, or even an outhouse, and be enveloped in saw- 
 dust until required. The ice must be taken from the top ; and 
 when tlie fir.st supply is obtained, a good (juantity of dry sawdust 
 should be placed over the crown. 
 
 Insect-Catching Device, A simple. — Cover the inside of an 
 old tub with liquid tar, and at twilight put a lighted lantern with- 
 in, leaving the whole out over night. The bugs, attracted by 
 the light, try to reach the lantern, and are caught and held fast by 
 the tar. 
 
 Insects on Plants, To discover. — If the leaves of the ])lant 
 seem reddish or yellow, or if they curl up, a close inspection will 
 generally disclose that the plants are infested by a very small 
 green insect, or else with red spider, either of which must be de- 
 stroyed. For this purpose, scald some common tobacco with wa- 
 ter until the latter is colored yellow, and when cold, sprinkle the 
 leaves of the ])lants with it. It is a gootl plan to pass tiie stems 
 and leaves of the plants between the fingers, and to then shake 
 the ])lant and well water the bed iinnKnliately afterward ; the lat- 
 ter operation destroys a large proportion of the insects shaken 
 from the plant. 
 
 Insects, To i)rotect cattle from. — Hub a very weak solution of 
 carbolic acid through the hair. 
 
 MANtiKi:, Salt as. — Salt should never l)e applied other than in a 
 ]>ulveroiis state, and never employed on impervious, cold, and hu- 
 mid soils. Tlie best manner to use it is to combine it with 
 other manures, a dose of 2 cwt. to the acre being sutRcieUt. 
 When selected to destroy insects, it should bo applied before 
 sunrisi!. In the casc! of cerr-als, suit strengthens tlie stems, and 
 causes the ears to fill iietter, and favors the dissolution and 
 aesimilation of the ])lios]>hates and silicates. It acts vigorously 
 on potatoes, and can be <lelected in tlu^ir ashes to the extent of 
 on*! half or one per ciuit. Asparagus is a verital)le glutton in tlie 
 |)reHenee of salt. .A <lose of '.'> cwt. j)er acre acts without fjiil on 
 beet, injuring its value for sugar ])nrposi-s hut enhancing it for 
 tlie fi'eding of cattle. <'td/,a has as marked a predilection for sail 
 
THE FARM. 213 
 
 as asparagus ; and in Holland, where the culture of peas is so ex- 
 tensive, salt is something like a necessity. Mixed with hay in 
 the proportion of 4 ozs. to 1 cwt., the fodder is more appetizing ; 
 but the best way to feed it to animals is to allow them to enjoy it 
 in the form of rock salt. 
 
 Manure, Soot. — Save the soot that falls from the chimneys, 
 when the latter are cleaned. Twelve quarts of soot to a hogshead 
 of water makes a good liquid manure, to be applied to the roots 
 of plants. 
 
 Manure. — The bodies of king crabs, often found along the sea- 
 shore, when decayed and mixed with sawdust, straw, muck, or 
 similar material, make an excellent manure. Land so poor that 
 no wheat could be grown on it, has been so enriched by the appli- 
 cation of this compost, that from 25 to 30 bushels to the acre 
 have been raised. 
 
 Moss ON Trees, To destroy. — Use a whitewash of quicklime and 
 wood-ashes. 
 
 Mowing Machines, Draft of. — The power required to drive a 
 mowing machine at work may be resolved into direct draft and 
 side draft. A good mowing machine should be so balanced be- 
 tween the driving wheels and the cutter bar, by placing the line 
 of draft nearer or further from the heel of the bar, that ordinarily 
 there will be little or no side draft. If so placed, the end of the 
 tongue will sometimes, when at work, be drawn toward the stand- 
 ing grass, and sometimes thrown away from it by the side draft. 
 Practically, side draft is of small account in a good machine. The 
 direct drait depends upon three causes, and may be resolved into 
 three parts : 1, The draft of the machine itself, on its own wheels, 
 on the ground ; 2, The power required to give motion to the gear- 
 ing and the knife ; 3, The resistance offered by the grass or other 
 substance cut. The power required to draw the machine on its own 
 wheels depends upon the size of the wheels, the perfection of the 
 axles, and the smoothness of the ground, and, other things being 
 equal, upon the weight of the machine ; and in a machine weigh- 
 ing 600 lbs., should not, on a smooth firm turf and level field, be 
 more than 75 to 100 lbs Adding to the weight of the machine 
 would add to the draft just in proportion, whether that added 
 weight be in the machine or in a driver on it. Suppose the ma- 
 chine to weigh 600 lbs. and the draft to be 80 lbs., put a driver of 150 
 lbs. on the seat, and you have increased the draft 25 per cent, or 
 to 100 lbs., while the power required to drive the knife and to 
 cut the grass remains unchanged, and you have only increased 
 the draft 20 lbs. The power to drive the knife and gearing de- 
 pends upon the perfection of the gearing and the weight and 
 velocity of the knife. A machine that in proper order may not 
 require more than 10 or 20 lbs. of power, may require ten or 
 twenty times that amount from deficiency of oil, collection of dirt 
 in the gearing, gum on the knife, or loosening of the connections 
 of the pitman by wearing or otherwise. The resistance of the 
 grass to be cut will vary with every change of condition, kind, and 
 thickness of grass, and every variation in the condition of the 
 knife and rapidity of stroke. The greater the velocity of a cut- 
 ting edge, after the velocity is once obtained, the less power is 
 
214 THE FARM. 
 
 required to do a given amount of work. The direct draft of a 
 good marhine, working under the most favorable circiuusiances, 
 has been determined by experiment to be less than 300 lbs. ; but 
 tliose favorable conditions are not always to be obtained, so that 
 tlie draft must many times be much heavier. The jiower of a 
 machine to cut, other things being equal, depends upon the hold 
 the wheels have upon the ground ; when the second and third 
 causes combined are sufficient to overcome the hold the wheels 
 have, the latter t^lide, the knife stops, the machine is clogged. 
 The heavier the machine, the less likely this is to occur ; putting 
 a heavy driver on the seat will sometimes carry a macliinc through 
 when with a lighter one it would clog. When the knife readies 
 the end of the stroke, its momentum is considerable, and it re- 
 quires nearly as much power to stop it as it did to start it to ii.ake 
 the stroke ; it would require quite as much if it were not for the 
 loss of some power by the friction of the knife in the guards. Now 
 if the joints of the pitman and connections are all perfect, this 
 stopping occurs when the crank passes the centre of the shaft 
 driving it, and the remainder of the momentum of the knife is 
 expended upon the crank in the direction of its length and at 
 right angles to the driving power, so that none of that is used up 
 in stopping the knife. But if these joints of the pitman are loose, 
 so that there is a little play, and the crank can pass the centre be- 
 fore the knife reaches the end of the stroke, this momentum will 
 be expended in opposition to the driving power, and will of course 
 increase the power necessary to work the machine by so much as 
 is necessary to overcome the momentum of the knife ; again, the 
 crank beginning to act upon the knife after it has passed the cen- 
 tre to make the return stroke, the knife must start with a greater 
 velocity, causing another loss. Xow, put the same machine into 
 the grass, and the grass operates to stop the knife as soon as the 
 crank allows it to stop, thus saving the momentum that was ex- 
 pended upon the crank in ojiposition to the driving jiower. and 
 also shortening the stroke and saving power that way. Supj)i)8- 
 ing, to illustrate, that there is a play of ^ inch in the joints, tlien 
 the knife running out of the grass will be thrown to the extreme 
 length each way, and will add 1 inch to the length of the stroke, 
 increasing the i)owcr necessary to make it. If it re(|uires a cer- 
 tain number of pounds power to make a stroke ot 3 inches in 
 length, it will require 33^ per cent more power to make a stroke 
 of 4 inches in length in the same time. ^Vhenever these amounts 
 of power lost in this way equal the power required to cut the 
 grass, tlien the machine will draw just as heavily out of the grass 
 as in it. From these premises many deductions nuiy be made as 
 to tlie care and practical use of mowing machines. 
 
 Nkst Kfu;s, To make. — Take an f)rdinary hen's cfXiS, break a 
 small hole in tlie small end, about ji of an incli in diameter, ex- 
 tract the <-ontents, and, after it is thoroughly dear inside, till it 
 with i)o\vdered slaked lime, tamping it in ordiT to inaki^ it con- 
 tain as much as possible. After it is full, seal it up witii jilasti-r 
 o' Paris, and you have a nest egg which can not he distinguisiied 
 by tile hen from tlu; other eggs, and one which will not crack 
 (like otlier aggB) by being frozen. 
 
THE FARM. 215 
 
 Onions, To transplant.— Plant them tightly in the soil, with 
 the leaves pointing to the north. When thus placed, after the 
 vegetables take root, the sun will draw the stalks vertical. 
 
 Oxen, Food consumed by. — An ox will consume 2 per cent of 
 his weight of hay per day to maintain his condition. If put to 
 moderate labor, an increase of this quantity to 3 per cent will en- 
 able him to perform his work and still maintain his flesh. If he 
 is to be fatted, he requires about 4^ per cent of his weight daily 
 in nutritious food. 
 
 Painting Boats. — Boats should be painted with raw oil. 
 Boiled oil used in the paint is very apt to blister and peel from 
 the wood. 
 
 Paris Green, To use. — In using Paris green to exterminate 
 the potato bugs, the poison should be mixed with the cheapest 
 grade of flour, 1 lb. green to 10 lbs. flour. A good way of 
 applying it to the plants is to take an old 2 quart tin fruit-can, 
 melt off the top, and put in a wooden head in which insert a 
 broom-handle. Bore a hole in the head, also, to pour the powder 
 in, and then punch the bottom full of holes about the size of No. 
 6 shot. Walk alongside the rows, when the vines are wet with 
 dew or rain, and make one shoot at each hill. 
 
 Pastures, Seeding. — Select varieties of seeds that spring up 
 in succession, so that a good fresh bite may be had from spring to 
 fall. 
 
 Pear Culture. — Pears have a tendency to crack when the 
 trees stand in soil which is deficient in lime and potash. Com- 
 mon wood-ashes contain these salts nearly in the proportions that 
 pear-trees on such soil require — 40 per cent of potash and 80 per 
 cent of lime. By applying wood-ashes at the rate of four hun- 
 dred bushels to the acre, after the fruit had formed and cracked, 
 the disease was totally eradicated by the next season. 
 
 Peat, Estimating quantity of. — Peat, as ordinarily in the bed, 
 will weigh from 2100 to 2400 lbs. per cubic yard ; and if drained 
 in the bed, 1340 to 1490 lbs.; and air-dried, 320 to 380 lbs., when it 
 will be found to be reduced to about i or ^ its original bulk. 
 
 Peat, Facts concerning. — When saturated with salt water, peat 
 is generally unfit for heating purposes. The fine, clay-like pow- 
 der found underlying peat-beds, of a yellowish white color, is 
 composed of shields of infusorial animalculjB, and forms a supe- 
 rior powder for polishing metals. In working a bed of peat, the 
 first step will be to ascertain if drainage is necessary ; and, se- 
 condly, how it can be effected and at the least cost. If the bed 
 can not be economically drained, resort must be had to mechani- 
 cal excavation. It is best not to drain a bed below the level to 
 which you can effectually work out in a season, unless you can 
 close the outlet drain to allow it to fill again with water for the 
 winter, for the reason that drained peat that has been frozen is 
 apt to disintegrate after thawing, and become impoverished for a 
 solid homogeneous fuel. Peat that has been well manipulated 
 and dried for fuel rarely holds more than 10 per cent of moisture, 
 and it will not afterwards become saturated with water, even by 
 immersion for an entire winter. A cubic yard of closely-packed 
 
216 THE FARM. 
 
 peat fuel will weigh from 1630 to 2180 lbs., and the heating value 
 of 1 lb. of such peat is equal to even 1^ lbs. wood ; one cord of 
 f/ood wood will weigh almost 4200 lbs. , and 1 cord of peat fuel 
 will weigh about 3750 lbs., showing a gain in space as well as in 
 greater heating power. 
 
 Plants, Creeping, Pegging down. — To propagate lobelias and 
 verbenas, the first bloom should-be picked off, and the branches, 
 as they extend, should be pegged down closely to the surface of 
 the mould. The branches will then take root as they lengthen, 
 and by thus drawing a large amount of sustenance from the soil, 
 they will bloom very freely and cover a large space. A verbena 
 may thus be made to cover a square yard, and a lobelia a square 
 foot of ground. 
 
 Plants, Iron and ashes for. — Wliite flowers, or roses, that have 
 petals nearly white, will be greatly improved in brilliancy by 
 providing iron sand and unleached ashes for the roots of growing 
 plants. Ferruginous material may be applied to the soil where 
 flowers are growing, or where they are to grow, by procuring a 
 supply of oxide of iron, in the form of the dark-colored scales 
 that fall from the heated bars of iron when the metal is hammer- 
 ed by tlie blacksmiths. Iron turnings and iron tilings, which 
 may be obtained for a trifle at most machine-shops, should be 
 worked into the soil near flowers, and in a few years it will be 
 perceived that all the minute fragments will have been dissolv- 
 ed, thus furnishing the choicest material for jiaintiiig flie gayest 
 colors of tlie flower-garden. If wood-ashes can be obtained readi- 
 ly, let a dressing be spread over the surface of the ground, about 
 lialf an inch deep, ami be raked in. 
 
 A dressing of quicklime will be found excellent for flowers of 
 every description. It is also of eminent importance to imj)rove 
 the fertility of the soil where flowers are growing, in order to 
 have mature, plump, ripe seed. Let the foregoing materials be 
 spread around the flowers, and raked in at any convenient period 
 of the year. 
 
 Plants, Potting. — Tlie mould for potting should be light and 
 loamy, tlie fertilizing material used being well decayed. If the 
 soil is rich of itself, it is belter to be eitlier very sparing with the 
 fertilizer or to dispense with it altogether. In tlu; bottom of tlie 
 put )»lace sfveral small broken pi(!ces of crockery or similar ma- 
 terial to assist tli(^ drainage ; and in setting the i)liint, be canfiil 
 to kee]) it well down in the pot, and to press the mould moderately 
 around the roots. Tlie surface of the mould should be about half 
 !Ui inch billow the level of the top of the flower-pot. Slijis should 
 lie planted close to the sides i)f the ]wi, and in small i)ots. When 
 a ]ilaiil becomes ])ot-l)oun(l, that is, when the roots have become 
 nialted around the sides and bottom of the ])ot, tlie ])lant, so soon 
 as it has ceased blooming, should be re-iiotted in a larger ]iot. It 
 is not neressfiry to remove any of th»> mould from the roots, but 
 siiii])ly to All in tlie space in the larf^er pot with new and rich 
 mould. 
 
 I'la.\T-1'i<()I1.( Toit, A newspaper.— A convenient number of 
 newHpajw'rs may be; jiasted together, and the edges folded over 
 strings, thus making a screen whidi, susi)endod ovisr tlie newspa- 
 
THE FARM. 217 
 
 pers spread loosely over the plants, would give the young shoots 
 an excellent protection in the severest cold weather, and from 
 the sun's rays in summer. 
 
 Plants, Selecting. — Choose those whose leaves are of a deep 
 green, and in all cases those which are short and bushy, and 
 have no bloom upon them. If, however, they are in bloom, cut 
 off thti flowers before pUmting, which will only delay the bloom- 
 ing a -tew days, and wiU greatly strengtheu the plant. If the 
 plants have been reared in a greenhouse or under frames, keep 
 them a few days before setting them in beds, placing them out of 
 doors in the daytime, and taking them in at night, in order to 
 make them hardy and prevent them suffering from the cool night 
 air. If the plants ar^' placed in a cold-frame, either before or 
 after being planted in the beds, be careful to lift the frame during 
 a great part of the daytime, otherwise the moisture which gathers 
 on the inside of the glass will fall upon the plants and infallibly 
 kill them by what is called dampness. 
 
 Plants, Treating unhealthy. — Mr. Peter Henderson, the cele- 
 brated horticulturist, says : Whenever plants begin to drop their 
 leaves, it is certain that their health has been injured either by 
 over-potting, over-watering, over-heating, by too much cold, or 
 by applying such stimulants as guano, or by some other means 
 having destroyel the fine rootlets by which the plant feeds, and 
 induced disease that may lead to death. If the roots of the plant 
 have been injured from any of the above-named causes, let the 
 soil in which it is potted become nearly dry ; then remove the 
 plant from the pot, take the ball of soil in which the roots have 
 been enveloped, and crush it between the hands just enough to 
 allow all the sour outer crust of the ball of earth to be shaken off ; 
 thi'U re-pot in rather dry soil (composed of any fresh soil mixed 
 with equal bulk of leaf-mould or street-sweepings), using a new 
 flower-pot, or having thoroughly washed the old one, so that the 
 moisture can freely evaporate through the pores. Be careful not 
 to over-feed the sick plant. Let the pot be only large enough to 
 admit of not more than an inch of soil between the pot and ball of 
 roots. After re-potting, give it water enough to settle the soil, 
 and do not apply any more until the plant has begun to grow, 
 unless, indeed, the atmosphere is so dry that the moisture has 
 entirely evaporated from the soil ; then, of course, water must 
 be given, or the patient may die from the opposite cause — starva- 
 tion. The danger to be avoided is in all probability that which 
 brought on the sickness, namely, saturation of the soil by too 
 much water. 
 
 Potatoes, Hoeing. — By drawing up the earth over the pota- 
 to in sloping ridges, the plant is deprived of its due supply of 
 moisture by rains, for when they fall the water is cast into the 
 ditf'hes. Further, in regard to the idea that, by thus earthing 
 up, the number of tubers is increased, the effect is quite the re- 
 verse ; for experience proves that a potato, placed an inch only 
 under the surface of the earth, will produce more tubers than one 
 planted at the depth of a foot. 
 
 Potato Sprouts, Poisonous. — The sprouts of the potato con- 
 tain an alkaloid, termed by chemists solanine, which is very poi- 
 
21?! THE FARAr. 
 
 sonous if taki'u into the system. Tl does not exist in the tubers 
 unless they are exposed to light and air, which sometimes occurs 
 from the accidental removal of tlie cartli in cultivation. 
 
 Potatoes, Stoi-incr. — A plan, tested successfully for eight 
 years, is to si)rinkle the floor with fine unslaked lime, over which 
 a layer of potatoes 4 or 5 inches in depth is spread. Then sprin- 
 kle again witli lime, and add another layer of potatoes the same 
 depth as before, and thus continue till the whole are disposed of. 
 The lime used is about one fortieth part by measure of the pota- 
 toes. 
 
 Potatoes thus treated have never become infected with disease, 
 and when disease was already existing it has not spread ; besides 
 which, tlie quality of the potatoes has been rather improved than 
 otherwise by the treatment, especially where they were watery 
 or waxy. 
 
 PorLTKV-lIousES, Purifying. — Lime is an excellent purifier, 
 and, when carljolic acid is added to the whitewash, willeflectually 
 keep away vermin from the walls. After every cleaning of the 
 floor it should be sprinkled Avith carbolic acid ; dilution, twenty 
 of water to one of acid. This is one of the best disinfectants and 
 antiseptics known, and is not used as much as it deserves. The 
 roosts should be sprinkled with it every week. This whitewash- 
 ing should be done twice at least, better three times a year. The 
 nests of sitting hens should be s])rinkled with carbolic acid to 
 keep off vermin ; and the; coops also, where young broods are kept 
 for a time, should l>e purified in this way. If a hen gets lousy, 
 the dilute acid will destroy the lice, if put under the wings, and 
 on the head and neck. Wood-ashi'S are excellent to be kept in 
 fowl-houses for hens to dust themselves with. They are much 
 more effectual than sand, but sand should also be kept for a bath. 
 
 Phopagating Plants. — To ])ropagate geraniums and calceo- 
 larias, do not let the plants flower too soon, but pinch off the 
 first appt^aring l)loom, and pinch out the eyes of all straggling 
 branches, which will immediately thr.>w out side-shoots, thus 
 forming very healthy and strong as well as good sha]>ed plants. 
 Givfi l)referen<f to thost^ plants Avhicli liave their liranches close 
 to the surface of the soil. 
 
 Pkunino Tukks. — The iJropcT cut is called the " clean cut," and 
 is made by cutting at an angh; of 45 , beginning at th(^ back of the 
 bud, and finishing slightly above it. When pruned in this way the 
 wound readily and raj)idly heals, and coinmeiuu^s tobe covered with 
 new wood as soon as the young bud i)ushes into growth. I'runing 
 should always be dmn- with a keen edged knife, holding the 
 shoot in the left han<l, and making one sliar|), (piicU ilriiw. 'J'lie 
 operation should be delayecl until the middh^ of February, and 
 jM^rfornied Ijetween tliat time and the niiildh^ of Marcli. 
 
 li.XTH, Kxterniination of, by bisulphiile of carl)on — In.sert a 
 lead pipe into llii^ iioles, and ]>our in Ijisnlphide of carbon. This 
 should only be usckI out of doors, nev(!r in buildings. An ounce 
 and a half of tlie li(|nid is sullicient to pour in at a tiin<\ 
 Where there are several holes near together, slop all but tlie Olio 
 in wliich the bisMlphide is ])oui('(l, with bricks. 
 
THE FARM, 
 
 219 
 
 Red Si'iDEKS, To extermiuate. — Syringe the plants freely with 
 water once or twice a day, taking care to wet the under side of 
 the leaves. Keep the air of the room moist, by setting pans of 
 Avater on the flues, heating-pipes, or register ; give all the light 
 possible, and ventilate freely whenever tlie weather will permit. 
 When the soil is dry, give sufficient water to moisten «all the soil 
 in the pot, and water no more until the surface is dry again. If 
 plants seem stunted or sickly, repot them in fresh, rich soil, or 
 use some other means to induce a healthy growth. The red spi- 
 der is any thing but an aquatic insect, and will yield to the hy- 
 dropathic treatment if it is persisted in. 
 
 Sand is the best substance in which to preserve carrots through 
 the winter. It should be perfectly dry. It will keep the roots 
 crisp and prevent softening. 
 
 Spawn-Carrying Device. — The apparatus represented here- 
 
 FISH-SPAWN CARRYING APPARATUS. 
 
 with is a new invention of Mr. Seth Green. It consists of a sim- 
 ple wooden box, of a convenient size to be carried in the hand by 
 means of tlie handle above. Its joints are covered with tin. Inside 
 are numerous small trays made of wood, covered below with can- 
 ton flannel. The upper tray, shown in the foreground, is pro- 
 vided with a hinged cover of the same materials. The spawn is 
 
220 THE FARM. 
 
 placed upon tlie bottom of the trays, together with moss or sea- 
 weed, and kept moist. The temperature of the room may be so 
 regulated that the spawn can be hatched in from 50 to 150 daya. 
 Bnidk-troiit, salmon trout, white-fish, and sahnon-eggs have beei) 
 irausported with success, over long journeys, by this means. 
 
 Skeds, Germination of. — The germination of seeds can be 
 watclied at every stage of its progress by laying tlie seeds between 
 moist towels and placing the latter between plates. The towels 
 can be lifted without damage to the tender sprouts. 
 
 Seeds, Vitality of. — Seed Vvili not germinate if they are too 
 old, and disappointment and delay often result. Experience of 
 seedsmen indicat< s that, if properly gathered and i)reserved, 
 beans will retain vitality 2 years , beet, 7 ; cabbage, 4 ; carrot, 2 ; 
 sweet corn, 2 ; cucumber, 10 ; lettuce, 3 ; mebjn, 10 ; onion, 1 ; 
 parsnip, 1 ; peas, 2 ; radish, 3 ; squash, 10 ; tomato, 7 ; turnip, 4. 
 
 Sheep, To protect from dogs. — An old sheep-raiser says that 
 the most efhcacious ])l;in is to ])rovide 15 <»r 20 sheep, in a flock 
 of 100, each with a globular bell about the size of a teacup. 
 
 Sleigh. — The length of the double whiffletree and the neck- 
 yoke for a sleigh should be just as long as the sleigh is wide 
 from the centn; (^i one runner to the other. 
 
 Slugs, Rose, To destroy. — Wood-ashes must be sifted on early 
 in the morning while the leaves are damp, the branches being 
 turned over carefully, so that the under sides of the leaves, to 
 which the young slugs cling, may get their share of the siftings. 
 If the night has hwn dew less, in order to make the work tho- 
 rough, first sprinkle the l)ushcs, and the ashes will then cling to 
 the slugs, to their utter destruction. 
 
 Stu.mps, Clearing oflE. — In the autumn, bore a hole 1 to 2 inch- 
 es in diameter, aceording to the girth of the stump, vertically in 
 the centre of the latter, and about 18 inches deep. Put into it 
 from 1 to 2 ozs. saltpetre ; fill the hole with water, and plug up 
 close. In the ensuing spring, take out tlie plug, pour in about | 
 gill kerosene oil and ignite it. The stuni]) will smoulder away, 
 without blazing, to the very extremity of the roots, leaving no- 
 thing but ashes. 
 
 Stables, To remove rank snu-ll of. — Sawdust, wetteil with sul- 
 |)huric acid, diluted with 40 ])!irts of wafer, and distributed about 
 horsc! stables, will remove; the disagre.ahle aninioniacal smell. 
 
 Suii-SoiL Dii.MN, A simple. — An exctdlent subsoil drain may 
 be made by digging a trench, ami fillinu^ in the bottom with 
 sticks of wood, compressing them together with tlie feet, and 
 then covering them with the mould. The effect! vene^s of .such 
 a drain will endure for several years, and the final decay of the 
 wood will serve to euriili the soil. 
 
 Si'MAc, ('ulti vatir)n and jireparation of. — Sunuic is largel\' used 
 in tanning the liner kinds of leather, esjx'cially in the manufac- 
 ture of the hard-grained nioniccf».s and similar goods. It is also 
 einploycid as th<; base of many (X)lorH in calico and (hhilni print- 
 ing. 'I'Ik! only trouble is in curing it ]>roperl\ . This must be 
 doiu! with all the care that is bi'sfowed upon tobacco or hop.s. 
 Exposure, aftiT cutting, to a heavy dew injures it, and a rain- 
 
THE FARM. 221 
 
 Storm detracts materially from its value. It is cut wlien in full 
 leaf ; and when properly dried is ground, leaves and sticks toge- 
 ther. An acre in lull bearing will produce not less than three 
 tons ; and when fit for market, it is worth from eiglity to one 
 hundred dollars a ton. The manufacturers, as the curers are 
 called, pay one cent a pound for it in a green state. The Com- 
 missioner of Agriculture advises to plant in rows, in order to cul- 
 tivate between, either by seed or cutting of the roots. We should 
 advise cuttings by all means, as sumac is as tenacious of life as the 
 blackberry or horse-radish. It will never need but one planting, 
 and the crop can be gathered any time from July to the time of 
 frost. If it is cut later in the season, and annually, the leaves 
 and the stocks can be ground together. If the cutting is delayed 
 until the stock has formed into solid wood, the leaves must be 
 stripped from the stock, and the stock is thus wasted. It is 
 doubtful if any thing is gained in the weight of leaves after the 
 middle of July, at which time almost every tree has completed 
 what is called first growth for the season. 
 
 Sumac, Mordants for dyeing with. — The mordants used for 
 dyeing with sumac are either tin, acetate of iron, or sulphate of 
 zinc. The first gives yellow, the second gray or black, according 
 to strength, and the third greenish-yellow. 
 
 Tools, Paint for. — White lead ground in oil, mingled with 
 Prussian blue, similarly prepared, to give the proper shade, and 
 finally mixed with a little carriage-varnish, is an excellent and 
 durable paint for farm-machinery and agricultural tools. 
 
 Trees, Felling. — To find the height at which a tree must be 
 cut, so that its top will strike a given point on the ground : 
 Square the height of tree, and the given distance from tree to 
 point. Divide the difference of these squares by twice the height 
 of tree, and the quotient will be the height from the ground 
 Avhere the tree has to be cut. Example : Height of tree =60 feet, 
 distance of point to the tree 20 feet ; then 60^=3600, 30-==400, 
 difEerence=3200. 3200^(2x60)=26.6 feet. 
 
 Trees, Fruit, To protect against mice. — Apply to the bark a 
 mixture of tallow, 3 parts, tar, 1 part, hot. 
 
 Trees, Girdled, To save. — If possible, bank up earth about 
 the trunk to above the level of the girdle. If the wounded parts 
 are too high, bind on clay with a bandage. The sooner the sur- 
 face is protected after injury the better. The death of the tree 
 is caused by the seasoning of the sap-wood. 
 
 Trees, Young, in hot weather. — If the trunk is fully exposed 
 to the sun, it should be protected from intense heat. A couple 
 of boards, tacked together like a trough and set up against the 
 trunk, will furnish the required shade ; or the trunk may be 
 bound with a hay-rope, or be loosely strawed up as for winter 
 protection. 
 
 Trichina in Pork, A cause of. — It has lately been found that 
 swine may become infested with trichinse through eating carrion, 
 or even decayed vegetable substances. This is a point worth 
 consideration by farmers who incline to the belief that dead 
 
222 THE FAKM. 
 
 chickens, putrid swill, or any otlier filth, about the place, is legi- 
 mate food for the pig. 
 
 TuRNiBS, To protect from fly. — Use lime, slaked just before 
 application. Sow it by hand over the plants ; or sow brimstone 
 with the seed. A simple way of removing the insects from the 
 plants is to mount a board two feet square on wheels, cover the 
 under side of the board with tar, and straddle it over the rows, 
 drawing it from end to end of the latter. The insects will jump 
 oil on the pitch and be caught. 
 
 Watekkall, To determine the height of, in a running stream. 
 — A small temporary dam, unless one exists, must be made, so 
 as to secure a still surface. Take two poles, sufficiently long to 
 reach from the bottom of the water to the required line-level. 
 Make a plain mark or notch on both sticks, at a distance from 
 the upper end equal to the distance of the intended line- level 
 above the water, marking that distance in feet and inches. Push 
 the poles down through the water into the earth at the bottom until 
 the notches are both at the level surface of the water, care being 
 taken to have the poles plumb and at a convenient distance apart. 
 Sight across the tops of these two, and set as many more as may 
 be desired to run the line of level to the desired jjoint, and the 
 tops being ranged accurately by the first two, will show a water- 
 level so many feet above that of the water. It is estimated that 
 this is a more accurate way than the use of the ordinary spirit- 
 level. 
 
 Water for Fisii-Ponds — Lead-pipe will not do to conduct 
 water to fish-ponds. It is likely to poison tlie fish. 
 
 Weeds, Destroying. — Some weeds can be killed and prevented 
 from growing in garden-patlis, by watering the ground with a 
 weak solution of carbolic acid, 1 part pure crystallized acid to 
 2000 parts water. Sprinkle from a watering-pot. 
 
 Worms, C'irrant and Goosereruy, liemedy for. — The best 
 is powdered white hellebore, obtainal)le at any druggist's. Put 
 the powder in a common tin cup, tying a juece of very fine muslin 
 over the mouth. Fasten the apparatus to the end of a short 
 stick, and dust the powder througii tht; musliu lightly upon the 
 bushes. Do not work on a windy day, and ."^tand to windward 
 during the operation, as, if taken into the nfj.'^trils, the hellebore 
 excites violent sneezing. The Bame material is a good remedy 
 for cucumber-beetles. 
 
HOUSEHOLD HINTS. 
 
 Ants, Red, To drive away. — Sprigs of wiutergreen or ground 
 ivy will drive away red ants ; branches of wormwood will serve 
 the same purpose for black ants. The insects may be kept out 
 of sugar-barrels by drawing a wide chalk mark around the top, 
 near the edge. 
 
 Aquarium, To make and stock an. — One of tlie first principles, 
 in constructing a tank for an aquarium, is to give the water tlie 
 greatest possible exposure to the air. The simple rectangular 
 form is the best. This is generally constructed of iron and glass ; 
 the iron should he japanned, and the glass be Freucli plate, to 
 insure brilliauey and strength. The breadth and height of the 
 tank should be about one half of the length. Cheap tanks can be 
 made of wood and glass, the frame and bottom being of wood, 
 and tlie sides of glass. In order to make the joints watertight, 
 care must be taken to" get a proper aquarium putty or cement. 
 The following is a good retipe : Put an eggcupf ul oil and 4 ozs. 
 tar to 1 lb. resin ; melt over a gentle fire. Test it to see if it has 
 the proper consistency when cooled ; if it has not, heat longer or 
 add more resin and tar. Pour the cement into the angles in a 
 heated state, but not boiling hot, as it would crack the glass. 
 The cement will be firm in a few minutes. Then tip the aqua- 
 rium in a different position, and treat a second angle likewise, 
 and so on. The cement does not poison the water. It is not ad- 
 visable to make the aquarium of great depth ; about eight inches 
 of water is sufficient. In regard to the light, great care must be 
 taken. Too much often causes blindness, and is a common 
 source of disease. The light fish receive in rivers comes from 
 above, and an aquarium should be constructed so as to form no 
 exception to this rule. All cross-lights should be carefully 
 avoided, at least if the light is very strong. Never place the 
 aquarium in front of a window so that the light passes through it ; 
 for, when viewing an aquarium, the source of light should 
 come from behind us. Not enough light is as injurious as too 
 much, and causes decay of the vegetation. Having constructed 
 a watertight aquarium, the bottom is strewn over with clean 
 sand to the depth of 1 to 3 inches ; on this a little gravel is 
 spread ; then a few stones or rock-work. Heavy large rocks 
 should be avoided ; they displace a large amount of water, and in- 
 crease the danger of breaking the glass sides. Pumice-stone, well 
 washed, is the best kind, being light and with a rough surface 
 suitable for the rooting of plants, etc. ; and if fancy forms are 
 desired (bridge- work, etc.). the pumice-stone can be cut quite easily 
 to the desired shapes. The plants are rooted in the sand and the 
 vessel left at rest for a week for the plants to vegetate. The fol- 
 lowing plants will be found useful : Utricutaria inflata, utricu- 
 
224 HOUSEHOLD HINTS. 
 
 Inria vulgaris, myyiopJiyUum spicat <m, anarcharis Canadensis, and 
 hottoida ii'flutii. 
 
 In obtaini^Ag' plants, procure all the roots and see that they are 
 well rooted. If fungus should form, add snails {planorbis tricol- 
 cis) ; they will completely destroy it. After the plants are well 
 started, add the shells and amphibious animals. The following 
 shells will be found desirable : Planorbis trivoldis,physa hetero- 
 stiiipha, uiiio complanatus. Many shells are not needed. Snails 
 act the part ot scavengers ; and where the different elements of 
 an aquarium are rightly balanced, two or more snails will be 
 found sufficient. 
 
 If amphibitjus animals are Introduced, the rock-work must ex- 
 tend above the surface of the water, or a float of some kind must 
 be substituted. It is impossible for them to live under water all 
 the time, and they would die without some such arrangement. 
 
 The turtles claim lirst rank. The enys punctatu, or spottel 
 water-turtle, and the clivysemys pieta, or painted water-turtle, 
 will be found to be the best for the aquarium, and should be pro 
 cured when very young, as they are very destructive when old. 
 The tritons {triton tiyrinus, triton iiiger), the red salamander, the 
 ciay-fish (/(.stttctis B(trtoni), are all suitable, and present a very 
 odd and yet a very natural look to the aquarium. 
 
 In selecting the fishes, a few only thrive in confinement. 
 Among these, and the first, is the gold-fish. He can live for 
 months without introduced food, and is, without comparison, the 
 most hardy, standing remarkable changes in the tem])eratur(! ; and 
 he is the most gaudy and attractive. A large number of the 
 fishes prey upon each other, and will only do for the aquarium 
 when in the young state. Among these may be mentioned pomo- 
 tis vulgaris, or sun-fish, csoxretir.ulatus, or common pickerel, and 
 j)erca Jlorcsccns, or yellow perch. The leuciscus pyi/nnfus, or roL-k- 
 fish, is a great addition, and is found very plentifully in our 
 streams. The jyimdvdus atrarius, or common black catfish, is 
 another worthy of a i)lace. So also is the hydr((rgia diaphana, 
 or transparent minnow. But few fish can live in an atiuarium, 
 and the needless crowding together, so often seen, is very hurtful 
 to healtli, and causes sound, strong fisli in a short time to become 
 weak and j)oi>r. The great difiiculty in keeping an aciuarium is to 
 secure enough oxygen for the fish. To a slight degree, it is the 
 duty of the plants to su))])ly this ; but if too much vegetation be 
 present, decomposition takes place and ruin follows. It has been 
 demonstrated that only a small amount is necessary to absorb the 
 carboni<' aciil given off by the fish and anii)liibians ; conseiiuently, 
 if tlni water be daily ai'-rated with a syringe, it will absorb an 
 abundant hupply of oxygen for the animal life, and the trouble 
 arising from the decay'of much vegetable matter will be lessened 
 or altogether avoided, 
 
 AciUAUlU.M, To mend broken glass of an. — Fasten a strip of 
 glass over the crack, inside the aquarium, using for a cement 
 white sludlac dissolved in ^ its w<ight of Venice turpentine. 
 
 AwNlNOH, WATKitruoOKiNf}. — Dip first in a solution contain- 
 ing 20 per cent soap, and afterwards in another solution contain- 
 ing the same percentage of copper. Wash afterwards. 
 
 1 
 
HOUSEHOLD HINTS. 225 
 
 Benzole, Necessity of care in use of. — Benzole is often em- 
 ployed for removing grease-spots. It is highly volatile and in- 
 tiammable ; so that the contents of a 4-oz. phial, if overturned, 
 will render the air of a moderate- sized room highly explosive. 
 Never handle it near a fire or light, as the tiame, igniting the 
 vapor from an uncorked bottle, will leap over to the latter, often 
 over a distance of several feet. 
 
 Bites, Rattlesnake, Remedy for. — The following is used by 
 soldiers on the plains, and is said to be efficacious : Iodide of 
 potassium, 4 grains ; corrosive sublimate, 2 grains ; bromine, 5 
 drachms. Ten drops, diluted with a tablespoonfiil or two of 
 brandy, wine, or whisky, is the dose, to be repeated if necessary. 
 Keep in a well-stoppered phial. 
 
 Boot Jelly and Shirt Coffee. — Some time ago. Dr. 
 Vander Weyde, of New-York City, regaled some friends not 
 merely with boot jelly, but with shirt coffee, and the repast was 
 pronounced by all partakers excellent. The doctor tells us that 
 lie made the jelly by first cleaning the boot, and subsequently 
 boiling it with soda, under a pressure of about two atmospheres. 
 The tannic acid in the leather, combined with salt, made tannate 
 of soda, and the gelatin rose to the top, whence it was removed 
 and dried. From this last, with suitable flavoring material, the 
 jelly was readily concocted. The shirt coffee, which we inciden- 
 tally mentioned above, was sweetened with cuff and collar sugar, 
 both coffee and sugar being produced in the same way. The 
 linen (after, of course, washing) was treated with nitric acid, 
 which, acting on the lignite contained in the fibre, produced glu- 
 cose, or grapi' sugar. This, roasted, made an excellent imitation 
 coffee, which an addition of unroasted glucose readily sweetened. 
 
 Boots, Waterproofing. — Use a piece of paraffine candle 
 about the size of a nut, dissolved in lard-oil at 140° Fahr. Apply 
 once a month. 
 
 Boots, To stop squeaking of. — Drive a peg into the middle of 
 the sole. 
 
 Boots, Wet. — When the boots are taken off, fill them quite 
 full with dry oats. This grain has a great fondness for damp, 
 and will rapidly absorb the least vestige of it from the wet 
 leather. As it quickly and completely takes up the moisture, it 
 swells and fills the boot with a tightly-fitting last, keeping its 
 form good, and drying the leather without hardening it. In the 
 morning, shake out the oats and hang them in a bag near the 
 fire to dry, ready for the next wet night ; draw on the boots, and 
 go happily and comfortably about the day's work. 
 
 Bottles cont.aining Resinous Solutions, To clean. — Wash 
 with caustic alkaline lyes and rinse with alcohol ; if they have 
 held essential oils, wash with sulphuric acid and rinse with 
 water. 
 
 BOTTLFS, Sealing. — Gelatine mixed with glycerine is used for 
 this purpose. This is liquid while hot, but an elastic solid when 
 cold. 
 
 BoTTi-ES, To cut in two. — Turn the bottle as evenly as possi- 
 ble over a low gaslight fiame for about 10 minutes ; then dip 
 
226 HOUSEHOLD HINTS. 
 
 Steadily in water, and the sudden cooling will cause a regular 
 crack to encircle the side at the heated phice, allowing the por- 
 tions to be easily separated. 
 
 Bottles, To prevent breakage in packing. — Slip rubber rings 
 over them. 
 
 BUHNS, Remedy for. — White lead rubbed to a paste in linseed- 
 oil. Another good remedy is as follows : Take the best white 
 glue (extra), 15 ozs. ; break it into small pieces, add to it 2 
 pints cold water, and allow it to become soft. Then melt it on 
 a water-bath, add to it 2 fluid ounces glycerine and 6 drachms 
 carbolic acid, and continue the heat on the water-bath until a 
 glossy, tough skin begins to form over the surface in the inter- 
 vals of stirring. The mixture may be used at once, after the 
 glue is melted and the glycerine and carbolic acid are added ; but 
 when time allows, it is advisable to get rid of a little more of the 
 water, until the proper point is reached. On cooling, this mix- 
 ture hardens to an elastic mass, covered with a shining parch- 
 ment-like skin, and may be kept for any time. When using it, 
 it is jilaced for a few minutes on the water-bath until sufficiently 
 liquid lor application. (It should be quite fluid.) Should it at any 
 time require too high a heat to become fluid, this may be corrected 
 by adding a little water. It is applied by means of a broad 
 brush, and forms in about two minutes a shining, smooth, flexi- 
 ble, and nearly transparent skin. It may be kept for any time, 
 without spoiling, in delf or earthen dishes or pots turned upside 
 down. 
 
 Butter, R.\ncid, To purify. — Melt in twice its weight of boil- 
 ing water and shake well. Pour the melted butter into ice- 
 water, to regain its consistence. Another : Wash in good new 
 milk, in which the butyric acid, which causes the rancidity, is 
 freely soluble. Wash afterward in cold spring-water. Another 
 plan is to beat up i lb. good fresh lime in a pail of water. Allow 
 it to stand for an liour, until the impurities have settled. Then 
 pour off the clear portion, and wash the butter in that. 
 
 Caps, P.vpek. To make. — Provide a sheet of moderately thick 
 brown paper, size from 18 inches to 2 feet, shape as in Fig. 1. 
 Smooth it out perfectly fiat, and double over as in Fig. 2. Turn 
 it round with the fold from you, and mark the exact middle of 
 tlie j)i('C<' at A, Fig. 3. Then bring down both corners, and 
 measure off mi the edge B from the point .\, Fig. 3, a distance 
 equal to ^ the circumference of your head. Mark the point. 
 Now turn tin- paper over so that tin- under side will be upper- 
 most, and bend the apex of the triangle back from the point just 
 marked, as in Fig. 4. Fold over tin; sides. Figs. 5 and (!, and 
 with scissors cut f)ff the portion, C, below the dotted lint*, 
 and also tlie points of th(! two lower corners of the pieces just 
 bent over. Next unfold the ])aper ; sprt'ad it out fiat : you will 
 find a square marked in the middle, and creases leading there- 
 from to the corners of the paper. Double up the material on 
 these cri-ases, so as tf) bring up the paper as sides of a box, of 
 which the iiiidille ^^l|uare is the bottom, as in Fig. 7. Smooth the 
 folds fiat, and your work will ap|)ear as in Fig. H. Lastly, turn 
 
HOUSEHOLD HINTS. 
 
 227 
 
 Fiq2 
 
 
 
 
 Fiq.S 
 
 Ficr.5. 
 
 MAKING PAPER CAPS. 
 
 up the edges of the box all around twice, folding the paper on 
 itself. Your cap is then complete, and if the measurement di- 
 rected above was correctly made, it will exactly fit your head. 
 
 Calico, To wash, without fading. — Infuse 3 gills of salt in 4 
 quarts of water. Put in the calico while the solution is hot, and 
 leave until the latter is cold. It is said that in this way the 
 colors are rendered permanent, and will not fade by subsequent 
 washing. 
 
 Carpets, To prevent moth in. — Wash the floor before laying 
 with spirits of turpentine or benzine. Do not do this with a fire 
 in the room, or with any matches or lights near. 
 
 Casks.— Rancid butter, pork, and lard casks may be purified 
 by burning straw or shavings in them. 
 
,228 HOUSEHOLD HINTS. 
 
 Cellars, Dry-rot in. — This, in cellar timbers, can be pre- 
 vented by coating the wood with whitewash to which has been 
 added enough copperas to give the mixture a pale-yellow hue. 
 
 Cellars, Testing, for dampness. — Provide yourself with a 
 thermometer, a glass tumbler filled with water, and a piece of 
 ice ; then notice how low your thermometer, when placed in the 
 tumbler, has to sink before any moisture begins to show itself on 
 the outside of the vessel of cold water. The lower the tempera- 
 ture to which the thermometer has to sink before moisture is 
 precipitated, the less there is of it in the moisture of the cellar. 
 
 Chair-Bottoms, To restore elasticity of cane. — Turn the 
 chair-bottom upward, and with hot water and a sponge wash the 
 cane ; work well, so that it is well soaked ; should it be dirty, 
 use soap ; let it dry in the air, and it will be as tight and firm as 
 new, provided none of the canes are broken. 
 
 Chapped Haxds. — Rub over with fine soap, and, while the 
 lather is still on, scrub the hands thoroughly with about a table- 
 spoonful of Indian meal. Rinse with tepid water, dry thorough- 
 ly, and wet again with warm water containing a quarter of a tea- 
 spoonful of pure glycerine. Dry without wiping, rubbing the 
 hands together until all the water has evaporated. Do this at 
 night before retiring, and the effect will be apparent by morn- 
 ing. 
 
 Chest-Protector, A simple. — A folded newspaper placed 
 over the chest inside the vest, on going out during raw spring 
 weather, constitutes an excellent protector for the lungs. 
 
 Chicken Feathers, Utilizing. — Cut the plume portions of the 
 feathers from the stem, by means of ordinary hand-scissors. The 
 former are placed in quantities in a coarse bag, which, when full, 
 is closed and subjected to a thorough kneading with tlie hands. 
 At the end of five minutes, the feathers become disaggregated 
 and felted together, forming a down perfectly homogeneous and 
 of great lightness. It is even lighter than natural eider-down, 
 because the latter contains the ribs of the feathers, which give 
 extra weight. About l.G troy ounces of this down can be ob- 
 tained from the feathers of an ordinarj'-sized pullet. It is sug- 
 gested that, throiigii the winter, children might collect all the 
 featlicrs about a farm, and cut the ribs out as we have stated. 
 By tlie spring-time, a large (]uantity of down would be j)repared, 
 wliich could be disposed of to upholsterers, or enii)]oyed for do- 
 mestic uses. Ooose-feathers may be treated in a similar manner, 
 and thus two thirds of tlie product of the bird utilized, instead of 
 r)nly aboutone fifth, as is at present thecase. Tiie chicken-down 
 is.^aid to form a beautiful cloth when woven. F<ir about a scjuare 
 yard of tin; material, a pound and a half of down is recjuired. 
 'I'iie fabric is said to be almost indestructible, as, in place of fray- 
 ing or wearing out at folds, it only seems to felt the tighter. It 
 takes dy(! readily, and is thoroughly water-i)roof. 
 
 Chkorv, Determination of, in ground coffee. — Gently strew 
 tlie powderupon the surfaceof cold water. Chicory, burntsugar, 
 etc., contain no oil, and their caramel is very (juickly extracted 
 by the water, witli jiroduction of a brown color, while the parti- 
 
HOUSEHOLD HINTS. 229 
 
 cles Hiemselves rapidly sink to tlie bottom of the water. On 
 stirring the liquid, coffee becomes tolerably uniformly diffused 
 without sensibly coloring the water, while chicory and other 
 sweet roots quickly give a dark-brown turbid infusion. Roasted 
 cereals do not give so distinct a color. 
 
 Chimneys, Burning, Prevention of. — The soot in the chimney 
 can not burn', except as the fire of the stove is communicated to 
 it through the pipe. If the pipe, therefore, be kept clean and free 
 from soot, and the damper in the stove always closed, the chim- 
 ney will never burn out. To free the pipe of soot, take the 
 stove-handle or any convenient implement, and rap the pipe 
 smartly on all sides from top to bottom. The soot will fall into 
 the stove and be harmlessly consumed, or it can be removed in 
 the usual way. 
 
 If there be a horizontal pipe, this should be taken down twice 
 a year and thoroughly cleaned. Or, if the pipe be only a few 
 feet in length, and the arrangements will admit of it, provide 
 the horizontal pipe with a permanent scraper, as follows : To the 
 end of a stout wire, a few inches longer than the pipe, attach a 
 small segment of a disk of sheet-iron, at right angles to the wire. 
 Eemove the elbow, and thrust the scraper into the pipe. Pass the 
 other end of the wire through a hole punched in the elbow, loop 
 the end of the wire for a handle, and replace the elbow. After 
 first rapping the pipe, the soot can all be drawn out and letfall 
 into the stove. Clean the pipe thus as often as once a fortnight 
 during cold weather. 
 
 Chimneys, Smoky stove or range. — To prevent smoking, use 
 a screen or blower of fine wire gauze, from 36 to 40 vdres to the 
 inch, immediately in front of the fire and about two inches there- 
 from. 
 
 Chimneys, Sooty, Cure for. — Plaster the inside with salt 
 mortar. The proportions used are 1 peck salt added, while tem- 
 pering, to 3 pecks mortar. Chimneys thus treated have re- 
 mained perfectly clean for fifteen years. 
 
 Clothes, Fire-proof wash for. — Four parts borax and 3 parts 
 Epsom salts, mixed with 3 or 4 parts warm water to 1 part of the 
 combined substances, is an excellent fire-proof wash for clothes. 
 It should be used immediately after preparation. 
 
 China and Glass Ware, Care of. — One of the most impor- 
 tant things is to season glass and china to sudden change of tem- 
 perature, so that they will remain sound after exposure to sudden 
 heat and cold. This is best done by placing the articles in cold 
 water, which must gradually be brought to the boiling point, 
 and then allowed to cool very slowly, taking several hours to do 
 it. The commoner tlie materials, the more care in this respect 
 is required. All china that has any gilding upon it may on no 
 account be rubbed with a cloth of any kind, but merely rinsed 
 first in hot and afterward in cold water, and then left to drain 
 till dry. It may be rubbed with a soft wash-leather and a little 
 dry whiting ; but this operation must not be repeated more than 
 once a year, otherwise the gold will most certainly be rubbed off, 
 and the china spoilt. When the plates, etc., are put away in 
 the china closet, pieces of paper should be placed between them 
 
230 HOUSEHOLD HINTS. 
 
 to prevent scratches on the glaze or painting, as the bottom of 
 all ware has little particles of sand adhering to it, picked up 
 from the oven wherein it was glazed. The china closet should 
 be in a dry situation, as a damp closet will soon tarnish the gild- 
 ing of the best crockery. In a common dinner-service, it is a 
 great evil to make the plates too hot, as it invariably cracks the 
 glaze on the surface, if not the plate itself. The fact is, when 
 the glaze is injured, every time the "things" are washed the 
 water gets to the interior, swells the porous clay, and makes tlie 
 Avhole fabric rotten. In this condition they will also absorb 
 grease ; and when exposed to further heat, the grease makes the 
 dishes brown and discolored. If an old, ill-used dish be made 
 very hot indeed, a teaspoonful of fat will be seen to exude from 
 the minute fissures upon its surface. These latter remarks apply 
 more particularly to common wares. 
 
 As a rule, warm water and a soft cloth are all that is required 
 to keep glass in good condition ; but water-bottles and wine-de- 
 canters, in order to keep them bright, must be rinsed out with a 
 little muriatic acid, which is the best substance for removing the 
 "fur" which collects in them. This acid is far better than 
 ashes, sand, or shot ; for the ashes and sand scratch the glass, 
 and if any shot is left in by accident the lead is poisonous. 
 
 Richly-cut glass must be cleaned and polished with a soft 
 brush, upon which a very little fine chalk or whiting is put ; by 
 this means the lustre and brilliancy are preserved. 
 
 Cider-Stains. — These may be removed by lemon-juice or 
 citric acid. 
 
 Cinders, Sifting. — To insure servants doing this, and to pre- 
 vent vegetable refuse being thrown into the ash-barrel, provide 
 a grated cover for the latter, which secure by a padlock to pre- 
 vent removal. 
 
 Cisterns, Cleaning. — This should be done just before warm 
 weather sets in, and should be done every year. 
 
 Clinkei{S, To remove, from stoves or fire-brick. — Put in about 
 half a peck of oyster-shells on top of a bright fire. This may 
 need rei)eating. 
 
 Clothing, Winter. — Sufficient clothing should be worn to 
 keep off a feeling of chilliness when about usual avocations. 
 Less than that subjects one to an attack of dangerous pneumonia 
 at any day or liour. More than tliat oppresses. Steadily aim, 
 by all possibh; ways and means, to keep oiT a feeling of chilli- 
 ness, wliidi always indicates that a cold has bt^en taken. 
 
 Clothes, Protective power of. — Clothes pn^tect tlie body, by 
 allowing through their interstices such ventilation tliat the 
 nervous system nuiy not be senHil)le to extremes in changes of 
 temperature. Dr. Petteukofer states that e(|ual sui-faces of vari- 
 ous materials are jxTuu'ated hy air as follows, (Ininiel Ix^iiig taken 
 as 100 : Linen of medium fineness, 58 ; silk, 10 ; buckskin, 58 ; 
 tanned loatlier, 1 ; chanujis leather, 51. 
 
 Clo'I'IIKs, |{eMovating old. — Two ozs. coiuiihmi tnitacco boiled 
 in 1 gallon water is UHc;d l)y the Chatham-street dealers for reno- 
 vating old clothes. Tlie stuil is rubbed on with a stiff brush. 
 
HOUSEHOLD HIKTS. 231 
 
 The goods are nicely cleaned, and, strange to add, no tobacco 
 smell remains. 
 
 Clothes, Washing compound for. — The German washerwo- 
 men use a mixture of 2 ozs. turpentine and 1 oz. spirits of 
 ammonia well mixed together. This is put into a bucket of 
 warm water, in whicli i lb. soap has been dissolved. The 
 clothes are immersed for 24 hours and then washed. The cleans- 
 ing is said to be greatly quickened, and 2 or 3 rinsings in cold 
 water remove the tui'pentine smell. 
 
 Cockroaches, To drive away. — Poke-root {p/iytolacca de- 
 candra), sliced thin and laid about a house, will destroy cock- 
 roaches quicker than any other poison. It never lails. Another 
 way of preparing the root is to boil 1 oz. in 1 pint water, until all 
 the strength is extracted. Mix with molasses, and spread on 
 plates in the localities infested by the insects. 
 
 Cork, To remove a, when pushed in a bottle. — When a cork 
 gets pushed down into the neck of a bottle, insert a loop of strong 
 twine and engage the cork in any direction most convenient. 
 Then give a strong pull, and the cork will generally yield suffi- 
 ciently to be withdrawn. 
 
 Corn, To can green. — Dissolve 2\ ozs. tartaric acid in a pint 
 of water. Of this solution, use 1 tablespoonful to every pint of 
 corn while the corn is at boiling heat. When opened for use, add 
 1 teaspoonful soda to every 3 pints of corn. 
 
 Cushions, Stuffing. — Flaxseed and tallow are used in Germany 
 as a stuffing for cushions. One part of tallow to 10 parts of flax- 
 seed are employed, the mobility of the greased seed rendering 
 the cushion very soft and pliable. 
 
 Disinfectant for the Breath, etc. — A very weak solution of 
 permanganate of pntasli is an excellent disinfectant for light pur- 
 poses, such as rinsing spittoons, neutralizing the taint of diseased 
 roots of teeth, cleansing the feet, and keeping the breath from 
 the odor of tobacco-smoke. Permanganate is not poisonous. 
 
 Engravings, To clean mildewed or stained. — Moisten the 
 paper carefully, and suspend it in a large vessel partially filled 
 with ozone. To evolve the latter, the simplest way is to clean 
 pieces of phosphorus and place them, half covered with water, in 
 the bottom of the jar in which the pictures are hung. On a large 
 scale, a Ruhmkorff coil, giving a constant discharge of electricity, 
 would be preferable. 
 
 Eye, To remove substances from the. — Take hold of the 
 upper eyelid, near its angles, with the index-finger and thumb of 
 each hand. Draw it gently forward, and as low down as possible 
 over the lower eyelid, and retain it in this position for about a 
 minute, taking care to prevent the tears from flowing out. 
 When, at the end of this time, you allow the eyelid to resume its 
 place, a flood of tears washes out the foreign body, which will be 
 found adhering to, or near, the lower eyelid. 
 
 Fermentation of Food. —This should be guarded against as 
 the warm weather approaches. This action is always liable to 
 cooked vegetables when set aside. Instead of warming up cold 
 messes, it is better to scald them. 
 
232 HOUSEHOLD HINTS. 
 
 Bugs, Fleas, etc. , To destroy. — This mixture, wliicli lias been 
 patented in France, consists of 80 parts of bisulphide of carbon 
 and 30 parts of essence of petroleum. 
 
 Floors, Cheap paint for. — This is made of 5 lbs. French ochre, 
 ^ lb. glue, and 1 gallon hot water. AVhen well dried, apply one 
 or two coats of linseed-oil. 
 
 Floors, Oak stain for. — An oaken color can be given to new 
 pine floors and tables by washing them in a solution of copperas 
 dissolved in strong lye, a pound of the former to a gallon of the 
 latter. When dry, this should be oiled, and it will look well for 
 a year or two ; then renew the oiling. 
 
 Floor Wax, Preparation of. — Heat to boiling 2 ozs. of pearl- 
 ash, 10 ozs. of wax, and i pint of water. Stir frequently, 
 until a thick fluid mass is formed from which, upon removal 
 from the fire, no watery liquid separates out. Add boiling water 
 cautiously, until no watery drops are distinguishable. Place on 
 the fire again, but do not allow to boil, and add by degrees 8 or 9 
 pints of water, stirring constantly. 
 
 Earthenware, Porous, To clean. — This often becomes foul 
 with organic matter when used to hold water. Use 1 oz. mu- 
 riatic acid, rubbed on exterior and interior with a piece of flan- 
 nel. Wash afterward with hot water. 
 
 Egos, To preserve. — Mix together in a tub or vessel 1 bushel 
 of quicklime, 32 ozs. of salt, 8 ozs. cream of tartar, with as much 
 water as will reduce the composition to a sufficient consistence to 
 float an egg. It is said that this treatment will preserve the eggs 
 perfectly sound for two years at least. 
 
 Flowkrs, Preserving. — The flowers must be carefully sur- 
 rounded by perfectly dry, fine sand, in such a manner that they 
 will h<»ld their form, the jtressure of tlie sand upon all surfaces 
 being alike. Any fine clean sand will answer ; it should be sifted 
 to remove all coar.se particles, and tlien washed in successive 
 waters until du.st and all earthy and clayey matters are washed 
 away, and the last waters when jioured off are perfectly clear. 
 The sand is then to be dried and then placed ovt-r a fire in a 
 proper vessel, until (juite hot, hotter than the hand can bear, 
 and wlien cool it will l)e fit to use. After heating, it should be 
 used at once, before it can absorb moisture from tlie air. Good 
 results have been obtained by takinj; a clean, thoroughly dry 
 flower-pot, the hole in the bottom r)f which was stopped by a 
 cork. This was filled a third full of the dry sand, the flowers 
 Het carefully in the sand, and then nior" sand slowly added, so as 
 to surround and cover tiie flowers inside and out, and set in a 
 warm place. At the end of 24 hours, the cork was removed 
 from llie liolo in the flower-pot, and the sand allowed to run out 
 in a small and gentle stream. The flower« were left in the pot, 
 jKjrfectiy dry. 
 
 Flv-Pai'kr, Adiiksive. — Smear paper with a mixture of mo- 
 lasBcs and linseed-oil. 
 
 Fk.\(imknts OK .Mktal, Extracting, from the flesh. — A simple 
 and u.-sually succis.sful modi- of extracting a n<-edle, or any jjieco 
 of steel or iron broken o(T in the flesh, ia accomplished by the 
 
HOUSEHOLD HINTS. 233 
 
 application of a simple pocket inaguet. Iron filings have a way 
 of imbedding themselves in the eye which defies almost every 
 ordinary means for their extraction. For their removal, a small, 
 blunt, pointed bar of steel, well magnetized, will be found excel- 
 lent, and we should reconmiend that workmen liable to such iu- 
 juries keep such an instrument about them. It would be a good 
 ])!an to insert such a bar in a penknife, in a manner similar to a 
 blade. 
 
 FnriT, Canning. — The following table for boiling fruit in cans 
 will douijtless prove useful. The first figure after the name of 
 the fruit refers to time of boiling in minutes, the second to 
 ounces of su;iar to the quart : Cherries, 5, 6 ; raspberries, 6, 4 ; 
 blackberries, 6, 6 ; gooseberries, 8, 8 ; currants, 6, 8 ; grapes, 10, 
 8 ; plums, 10, 8 ; peaches (whole), 15, 4; peaches (halves), 8, 4; 
 pears (whole), 30, 8 ; crab-apples, 25, 8 ; quinces (sliced), 15, 10 ; 
 tomatoes, 30, none ; beaus and peas, 3 to 4 hours. 
 
 Furnace Heat, To moisten. — Dry furnace heat, productive of 
 throat and lung diseases, may be moistened by hanging a wet 
 towel in front of the register," the lower edge of the towel being 
 allowed to dip in a shallow vessel of water. 
 
 Fttrnace, To prevent rust in a. — Throw some quicklime loose- 
 ly on a board, and place inside the furnace. 
 
 Furniture, Refinishing oiled or varnished. — Oiled furniture, 
 scratched or marred, may be restored by rubbing with a woolen 
 rag dipped in boiled linseed-oil. Varnished, by similarly rubbing 
 with a varnish of shellac dissolved in alcohol. 
 
 Fabrics, To make uninfiammable. — The lightest materials are 
 rendered uninfiammable by washing in a concentrated neutral so- 
 lution of tungstate of soda, diluted with about one third of water, 
 and then mixed with 3 per cent of phosphate of soda. 
 
 Feet, Frosted.— These can be relieved of soreness by bathing 
 in a weak solution of alum. 
 
 Ferns, Ornaments made of. — Handsome ornaments can be 
 made by mounting fern-leaves on glass. The leaves must first 
 be dyed or colored. They are then arranged on the mirror ac- 
 cording to fancy. A buttcrfiy or two may be 'added. Then a 
 sheet of clear glass of the same size is placed on top, and the two 
 sheets secur d together at the edges and placed in a frame. 
 
 Fire-Alarm, A simple and good. — An old gun loaded with a 
 heavy charge of powder, and hung near the ratters in a barn, or 
 in any dangerous locality about tlie house, makes an excellent 
 fire-alarm. The explosion is caused by the heat. 
 
 Fire, Extinguishing. — A solution of pearlashin water, thrown 
 upon a fire, extinguishes it instantly ; the proportion is 4 ozs., 
 dissolved in hot water, and then poured into a bucket of common 
 water. 
 
 Fires, Kerosene. — Never try to extinguish a kerosene fire with 
 water. Smother the flames with blankets or rugs. 
 
 Fire, Precautions in case of. — Keep all doors and windows of 
 the structure closed until the firemen come ; put a wet cloth over 
 the mouth and get down on all fours in a smoky room ; open the 
 
234 HOUSEHOLD HINTS. 
 
 upper part of tlie window to get the smoke out. If in a theatre, 
 keep cool. Descend ladders with a regular step, to prevent vibra- 
 tion. If kerosene just purchased can be made to burn in a sau- 
 cer by iirniting witli a match, throw it away. Put wirework over 
 gaslights in show-windows ; sprhikle sand instead of sawdust on 
 floors of oil stores ; keep shavings and kindling-wood away from 
 steam-boilers, and greasy rags from lofts, cupboards, boxes, etc. ; 
 see that all stove-pipes enter well in the chimney, and that all 
 lights and fires are out before retiring or leaving place of busi- 
 ness ; keep matches in metal or earthen vessels, and out of the 
 reach of children ; and provide a piece of stout rope, long enough 
 to reach the ground, in every chamber. Neither admit any one, 
 if the house be on fire, except police, firemen, or known neigh- 
 bors ; nor swing lighted gas-brackets against the wall ; nor leave 
 small children in a room where there are matches or an open fire; 
 nor deposit ashes in a wooden box or on the floor ; nor use a light 
 in examining the gas-meter. Never leave clothes near the fire- 
 place to dry ; nor smoke or read in bed by candle or lamp light ; 
 nor put kindling-wood to dry on top of the stove ; nor take a 
 light into a closet ; nor pour out liijuor near an open light ; 
 nor keep burning or other inflammable fluids in a room where 
 there is a fire ; nor allow smoking about barns or warehouses. 
 
 Fires, Usual causes of. — Churches and lecture-rooms of all 
 descriptions. — Hot air, hot water and steam i>ipes, and furnaces 
 and stoves. Sticking candles against coffins in vaults. Christ- 
 mas and other decorations around or too near gas-fittings, fires, 
 or lights. Sparks falling upon birds' nests in spires andbellries. 
 Curriers and workers in leather. — Lime slaked by rain. Sparks 
 from foul fines and furnaces jjassing through opening and ] ro- 
 jecting eaves of drying-rooms. Friction of niacliinery in bark- 
 mills. Timb(n-, coals, shavings of wood, and leather too nearfiue.^. 
 Drying stoves and furnaces. Spontaneous ignition. Smoking in 
 bark and other rooms. 
 
 Drapers, tailors, makers up and vendors of male and female iit- 
 tire. — \N'orking late, being tired and falling aslecj), or becoming 
 careless too way iires and lights. Unprotected and swinging gas- 
 brackets. Crinolines coming in contact witli fire in op:,'n fire- 
 places. Light, ])endent goods being l)lown, by tlie o])ening and 
 shutting of d(K)rs or Ijy concussions or drafts, into unprotected 
 liglits. (ioods hung on lines increase the risk in various ways, 
 Hucli as conveying the fiame from one end of a room to tlie 
 other, and, wiien tin; line lireaks down, making three sej)arate 
 fires, one ut eacli end and one in the middle at the same time, 
 thus originating three distinct fires for CHch line. Cuttings left 
 carelessly a])out. Using lights while intoxicated, esp(;cially by 
 tailors' work-])eo])l(!. Ironing-stoves, liot jilates, smoothing-irons, 
 etc., loo near and sometimes on timber and goods. Smoking-to- 
 bacco, and niatdn-s for lighting it. 
 
 Engineering irarks, and irorkern in metal if all descriptions. — 
 Sparks from striking liot metal, liot metal castings, etc., left too 
 near timber. Heat from furnaces, forges, and smitlis' hearths and 
 flues. Friction of nnichinery. .lapunners' stoves overln^ated or dt;- 
 fective. Accidents with inelti'd or hot metal. lOxjjIosions of lilast 
 furnaces. Sifontaneous ignition of oily waste, moulders' lamp, and 
 
HOUSEHOLD HINTS. . 235 
 
 Other blacks ; sawdust or sweepings and oil ; spontaneous heating 
 of iron turnings, etc., when mixed with water and oil. 
 
 Farming -stock, stables, My, yrain, or flour stores of^ all descnp- 
 tions. — Stacking hay while green. Sparks from passing locomo- 
 tives, etc. Sparks "from steam thrashing machines. Sticking 
 candles against walls and timber in barns and stables. Vagrants 
 smoking in stables. Vagrants being refused alms. Fire-arms 
 used near farming-stock, such as haystacks, etc. 
 
 Makers of gunpowder, firetcorks, lucifer matches, and explosive 
 compounds. — Overheating of drying-stoves and explosive mix- 
 tures. Dropping lucifers. Unprotected lights. Smoking. Leav- 
 ing phosphorus uncovered with water. Friction and percussion 
 from nails in boots. Sparks passing through broken windows. 
 The sun's rays being concentrated through bull's-eyes, knots, 
 etc., in glass.' Defective casks containing gunpowder or other 
 explosive materials. Spontaneous ignition of red fire and such- 
 like compositions. Carelessness in the supervision of young 
 children employed. Shavings and chips too near fires and lights. 
 
 Gas-works. — Hot coke near timber, etc. Seeking for an escape 
 with unprotected lights. Timber too near furnaces, retorts, etc. 
 Lime slaked by raiu. Defective fittings and appliances. Spon- 
 taneous ignition of coals. 
 
 Hat manufactories. — Boiling shellac. Hot irons left on timber 
 and other inflammable things. Defective drying and other stoves. 
 Smoking tobacco. 
 
 Fishing, Comfortable. — A plan practiced on the Western 
 lakes in winter consists in having a small house, built on run- 
 ners like those of a sled, in which is placed a small stove, while 
 in the floor a small aperture is left through which to drop the 
 lines. Holes are cut in the ice, the houses are moved over them, 
 and the fishermen sit by a warm stove while drawing in the fish. 
 
 Fish, Gold, Treatment of. — Seth Green says this as to the 
 proper care and treatment of gold-fish : " Never take the fish in 
 your hand. If the aquarium needs cleaning, make a net of 
 mosquito-netting and take the fish out in it. There are many 
 gold-fish killed by handling. Keep your aquarium clean, so 
 that the water looks as clear as crystal. Watch the fish a little, 
 and you will find out when they are all right. Feed them all 
 they will eat and any thing they will eat — worms, meat, fish- 
 wafer, or fish-spawn. Take great care that you take all that they 
 do not eat out of the aquarium ; any decayed meat or vegetable 
 in water has the same smell to fish that it has to you in air. If 
 your gold-fish die, it is attributable, as a rule, to one of three 
 causes — handling, starvation, or bad water." 
 
 Fishing-Lines, To water- proof. —Apply a mixture of 2 parts 
 boiled linseed-oil and 1 part gold size ; expose to the air, and 
 dry. 
 
 Flannels, To wash. — Take soft water, as warm as you can 
 bear your hands in. Make a strong suds, well blued. In wash- 
 ing fine flannels, wet but one piece at a time ; soap the dirty 
 spots and rub witli the hands, as washboards full the flannels. 
 When half clean, add three times as much blue as for cotton 
 clothes. Use plenty of soap. When clean, have ready a rinse of 
 
236 HOUSEHOLD HINTS. 
 
 the same temperature as the suds, rinse well, wruig tight, shake 
 briskly for a few minutes, hang out in a gentle breeze. When 
 nearly dry, roll smooth and tight for an hour or two. Press with 
 a moderately hot iron. If embroidered, press on the wrong side. 
 Flaimels washed in this way will look white and clean when 
 worn out, and the quality will look better than when new. 
 
 Garbage, To dispose of. — When not fed to pigs, the best way 
 to get rid of kitchen refuse is to burn it in the range or stove. 
 
 Gas Escaping, To detect. — To find the leak, first see that no 
 burners have been left accidentally turned on. This is often the 
 case where the cock has no stop, and is caused by the cock being 
 partially turned around again so as to open the vent. Imperfect 
 stop-cocks for this reason are dangerous, and should be promptly 
 repaired. Try all the joints of the gas-fittings, by bringing a 
 lighted match near them, to ignite the escaping gas if any there 
 be. In case it is found by the sense of smell that the gas is 
 escaping either within the floor or walls, do not on any account 
 apply a match near a crevice. Turn off the gas at the metre, 
 and send for a gas-fitter at once. In ordinary leaks, the burner 
 or joint should be unscrewed, and white lead or common bar- 
 soap rubbed in the threads before screwing home again. 
 
 (jrAS-LiGHT, Average prices of, in the United States. — Maine, 
 $3.87. New- Hampshire, $3.9(). Vermont, $-1.80. Massachusetts, 
 $3.86. Rhode-Island, $3.35. Connecticut, $-4.03. New- York, $3.88. 
 New Jersey, $3.80. Pennsylvania, $3.46. Delaware, $3.95. Mary- 
 land, $3.59. Dist. of Columbia, $3.16. Virginia, $3.89. West- 
 Virginia, $3.11. North-Carolina, $6.67. So'uth-Carolina, $3.80. 
 Georgia, $5.07. Fl(n-ida, $S.O0. Alaliama, $4.83. Mississippi, 
 $5.25. Michigan, $3.43. W^isconsin, $3.87. Ohio, $3.33. Indiana, 
 $8.54. Illinois, $3.87. Kentucky, $3.92. Tennessee, $4.06. Min- 
 nesota. $4.31. Iowa, $4.52. Missouri, $3.95. Arkansas, $5.00. 
 Louisiana, $4.50. Texas, $5.75. Kansas, $4.55. Colorado, $5.00. 
 Utah, $4.00. California, $6.11. 
 
 Total average net price of gas in the United States, $4.32*. 
 
 Gilt Frames, To restore. — Rub with a sponge moistened in 
 turpentine. 
 
 Gl.\ss, To break in any required form. — Make a small notch, 
 by means of a file, on the edge of a piece of glass ; then make 
 the end (if a tiihacco ])i])(', or a rod of iron about the same size, 
 red-hot in the fire, a])])ly the hot iron to the notch, and draw it 
 slowly along the surface of the glass in any direction you 
 please ; a rrack will Ix; made in the glass and will follow the di- 
 rection of the iron. Round glass bottles and flasks may be cut in 
 tiic middle by wrap])ing round them a worsted thread dipped in 
 spirits of turpentine, and setting it on lirt' wlien fastened on the 
 glass. 
 
 (iLAHS Jars, To cut. — Fill the jar with lard-oil to where you 
 want to cut the jar ; then heat, an iron rod or l)ar to red heat, im- 
 merse it in the oil ; the unefpiiil exi)ansion will rlieck the jar all 
 round at the surface! of the oil, and you can liftoff the top part. 
 
 (ii.Ass, To cut without a diamond. — Hold it level under water, 
 and, with a pair of scissors, dip it away by small bits from the 
 edges. 
 
HOUSEHOLD HINTS. 23*7 
 
 Grease-Spots on Clothing, To remove. — In using benzole or 
 turpentine, people make the mistake of wetting the cloth with 
 the turpentine and then rubbing it with a sponge or piece of 
 cloth. The only way to radically remove grease-spots is to place 
 soit blotting-paper beneath and on top of the grease-spot, which 
 spot has first been thoroughly saturated with the benzole, and then 
 well pressed. The fat gets now dissolved and absorbed by the 
 paper, and entirely removed from the clothing. 
 
 Hams, Pickle for curing. — An excellent, well-recommended 
 pickle for curing hams is made of 1^ lbs. of salt, i lb. of sugar, 
 I oz. of saltpetre, and i oz. of potash. Boil all together till the 
 dirt from the sugar has risen to the top and is skimmed. Pour 
 it over the meat, and leave the latter in the solution for 4 or 5 
 weeks. 
 
 Heaeths, Soapstone, To wash. — Use pure water, and then 
 rub with powdered marble or soapstone put on with a piece of 
 the same stone. 
 
 Hearths, To clean gray marble. — Kub with linseed-oil, and no 
 spots will show. 
 
 Ice-Water, To preserve. — Make a hat-shaped cover of two 
 thicknesses of paper, with cotton batting ^ inch thick between. 
 Place over the entire pitcher 
 
 Incubator, A cheap. — One of the easiest constructed forms 
 of incubator for the artificial hatching of eggs consists simply of 
 a cask well buried in a manure-heap. In the bottom of the cask 
 place one or two sieves to hold the eggs, and make a door in the 
 side for the removal of chickens, etc. A pane of glass may also 
 be inserted either in the do<ir or at any convenient point for view- 
 ing the interior. In the head, which should be removable, make 
 an opening provided with a sliding cover, for regulating the size 
 of the aperture, as may be necessary. Form a bed of fresh 
 manure about 1 ft. thick (after bedding) and 6 ft. scjuare. On 
 this set the cask, and pack more manure around the latter until 
 flush with the top. Now take off the head or cover and place a 
 thermometer on one of the sieves. Replace the cover. The 
 natural heat of the manure will warm the interior of the cask. 
 When the temperature reaches 104' (seen by the thermometer), 
 place the eggs on the sieves. The hatching process then begins, 
 and lasts the usual time. Care should be taken to turn the eggs 
 over once a day, and to allow them to cool slightly, thus imitat- 
 ing the natural habit of the hen when she leaves her nest in 
 search of food. The temperature of the interior is kept uniform 
 at 104° by removing manure from the side of the cask to lessen 
 the heat, or by substituting manure fresh from the stables in 
 place of the older material, in order to increase the warmth. 
 
 After the chickens have emerged from the shell, the inte- 
 rior of the cask should be carefully cleaned, and an artificial 
 " mother" placed inside. This last "consists of a loosely-fitting 
 disk of wood, covered on its under side with sheepskin or a piece 
 of buf?alo-robe. Under it the chickens nestle. It may be sup- 
 ported from the head by a piece of cord, or by a rod held in 
 clamps, so that its distance from the bottom of the cask may be 
 
238 HOUSEHOLD HINTS, 
 
 adjusted to suit. The warmtli necessary for the young chickens 
 is maintained by the manure, so that the hitter answers both for 
 this purpose and foi- the hatching. The slide mentioned above, 
 as located in the head of the cask, is intended for ventilating the 
 interior. 
 
 This plan is now in practical operation on one of the largest 
 poultry farms in the country and i.s evidently more simple than 
 any other involving the use of s])ecial a])i)aratus and gas or lamps 
 for heating. A cylindrical vessel must be used— never a square 
 one, since the chickens, in the latter case, will crowd into corners 
 and smother each other. The number of (yggs hatched depends 
 upon the size of the cask or the number of casks used. As many 
 as one thousand eggs have been thus incubated at a time. Any 
 farmer having a manure-heap, however small, can easily test the 
 plan, if only with a dozen eggs. The matter requiring the 
 greatest care is to keep the temperature in the cask uniform, and 
 to have the manure sheltered from rain, which would cool it. 
 
 Ink, Indelible, To remove. — If the ink is a nitrate of silver 
 preparation, it may be taken out of the fabric (1) by washing the 
 latter in a solution of hyposulphite of soda, or (2) by moistening 
 it with a solution of bichloride of cojiper, and then washing it 
 with liquid ammonia. 
 
 Ink-Stains, To remove, from mahogany. — Put a few drops of 
 spirits of nitre in ateaspoonful of water, touch the spot with a fea- 
 ther dipped in the mixture, and, on the ink disappearing, rub it 
 over inmiediately with a rag wetted in cold water, or there will 
 be a white mark which will not easily be effaced. 
 
 Ink-Stains, To remove. — Wasli carefully with pure water, and 
 apply oxalic acid ; and, if the latter changes the dye to.a red 
 tinge, restore the color by ammonia. 
 
 Insect Bites. — A good remedy is borax, 1 oz., dissolved in 1 
 pint water previously boiled and allowed to cool. 
 
 Keys, Fitting. — Wln-n it is not convenient to take a lock apart 
 to fit a new key, the key-blank shouUl be smoked over a can(lU\ 
 inserted in the keyhole, and ])ressed firmly against tiie opposing 
 wards of the lock. The indentations in the smoked portion made 
 by the wards will show where! to file. 
 
 Lamp-Burnehs, To fasten kerosene. — Plasttsr of Paris mixed 
 with resin soap is a good cement for this purpose. 
 
 Lkad-Comc, Preventives of. — If working in lead, wash the 
 liands several times a day in a strong decoction of oak-bark. 
 Keep the liair short, and (if a ])ainler) wear a clean cloth cap. 
 Tlie clothes should be freciuently washed, and tiie liands also, es- 
 jx-cially before touching food. Befon^ eating, the moutli sliould 
 be rinsed with cold water. A weak oak i)ark di'coctioii sliouhl be 
 usi'd as a wasli si'vcral tinn-saweek. 'I'iie l)ndy sliould be sponged 
 niglit and morning with cold or te]>id water, and the liair tho- 
 rouglily wasiied evtTy (!V(uiing afttsr work. Tlie food should con- 
 tain a large proportion of fatty substances, and milk should be 
 taken in largt? (]uaiitilies. 
 
 liEAK AM) Flowkk Imi'KEHSIONS, To make. — Take a small 
 quantity of printer'n ink, thinly put it on glass, evenly distribut- 
 
HOUSEHOLD HINTS. 239 
 
 ed. The end nf the index-finger will serve as the printer's ball, 
 to cover one side of the leaf uniformly ; then lay it to the exact 
 place where you wish the print to be ; lay over it a piece of thin, 
 soft paper large enough to cover it ; then, without moving the 
 leaf, press all parts of it with the end of the thumb firmly, and 
 you will have a perfect impression, that no engraver can excel ; 
 and by adjusting the leaves at the proper points, accurate prints 
 can be taken, and, aided with the brush or pen, the stem and 
 whole plant can be shown. Excellent specimens of impressions 
 of barks of trees can be made by slicing the bark ; and with a 
 little care, the stems can also be taken, as well as flowers. When 
 colored with the aniline colors, they are very like colored en- 
 gravings. 
 
 Leather, To water-proof. — Saturate with castor-oil. This is 
 excellent for winter boots. 
 
 Life Preserver, A simple.— It is not generally known that, 
 when a person falls into the water, a common felt hat can be 
 made use of as a life-preserver. By placing the hat upon the 
 water, rim down, with the arm around it pressing it slightly to 
 the breast, it will bear a man up for hours. 
 
 Linen, To bleach. — Javelle water, used for turning white the 
 dirtiest linen and removing stains, is composed of bicarbonate of 
 soda, 4 lbs. ; chloride of lime, 1 lb. Put the soda into a kettle over 
 the fire, add 1 gallon of boiling water, let it boil from ten to fif- 
 teen minutes, then stir in the chloride of lime, avoiding lumps. 
 Use when cool. This is good for removing fruit-stains from 
 white underwear. 
 
 Marble, To clean. — Common soda, 2 parts ; pumice-stone (pul- 
 verized), 1; finely powdered chalk, 1. Sift through a fine sieve, 
 and mix with water. Rub all over the marble until the stains 
 are removed. Then wash the stone with soap and water. Marble 
 that is yellow wnth age, or covered with green fungoid patches, 
 may be rendered white by first washing it with a solution of per- 
 manganate of potash of moderate strength, and while yet moist 
 with this solution, rubbing with a cloth saturated with oxalic 
 acid. As soon as the portion of the stone operated upon becomes 
 white, it should be thoroughly washed with pure water to re- 
 move all traces of the acid. 
 
 Match-Scratchers. — The best are pieces of shark-skin, or 
 squares of fine wire gauze. 
 
 Mice, To kill. — Sprinkle some grain near the holes, and throw 
 near by a few bits of cotton saturated in chloroform. This has 
 been tested, and mice have been found dead, two or three at a 
 time, lying with their noses near the cotton. 
 
 Mildew, To remove. — Make a very weak solution of chloride 
 of lime in water (about a heaping teaspoonful to a quart of 
 water), strain it carefully, and dip the spot on the garment into 
 it ; and if the mildew does not disappear immediately, lay it in 
 the sun for a few minutes, or dip it again into the lime-water. 
 The work is effectually and speedily done, and the chloride of 
 lime neither rots the cloth nor removes delicate colors, when 
 
240 HOUSEHOLD HIJfTS. 
 
 sufficiently diluted aud the articles rinsed afterward in clear 
 water. 
 
 Moss Ornaments. — A beautiful orr anient for tlie sittinjr-room 
 can be made by covering a common glass tumbler with moss, tlie 
 latter fastened in place by sewing-cotton wound around. 'I'hen 
 glue dried moss upon a saucer, into which set the tumbler, filling 
 it and the remaining space in the saucer with loose earth from 
 the woods. Plant tlie former with a variety of ferns, and the 
 latter with wood-violets. On the edge of the grass also plant 
 some of the nameless little evergreen vine, which bears red 
 (scarlet) berries, and whose dark, glossy, ivy-like foliage will 
 trail over the fresh blue and white oi the violets with beautiful 
 effect. Another good plan is to fill a rather deep plate with some 
 ot the nameless but beautiful silvery and light green and delicate 
 pink mosses, which are met with in profusion in all the swamps 
 and marshes. This can be kept fresh and beautiful as long as it 
 is not neglected to water it profusely once a day. It must, of 
 course, be placed in the shade, or the moss will blanch and die. 
 In the centre of this, a cliinip of large azure violets should be 
 placed, adding some curious lichens and pretty fungous growth 
 from the barks of forest-trees, and a few cones, shells, and 
 pebbles. 
 
 Mosquitoes, To drive off. — Rub the skin with essence of penny- 
 royal, or with a little coal-oil on a bit of cotton. The smell of 
 the oil disappears in a few minutes. 
 
 Mustard Poultice:, To make a. — In making a mustard plaster 
 use no water, but mix the mustard with white of egg, and the 
 result will be a plaster whicli will draw perfectly, but will not 
 produce a blister, no matter how long it is allowed to remain. 
 
 Mucilage, Pocket. — Boil 1 lb. best white glue, and strain very 
 clear ; boil also 4 oz. isinglass, and mix the two together ; i)lace 
 them in a water-bath (glue-kettle) with ^ lb. white sugar, and 
 evaporate till the liquid is quite thick, when it is to be poured 
 into moulds, dried, and cut into pieces of convenient size. This 
 immediately dissolves in water, aud fastens paper very firmly. 
 
 Newspaper Binder, Temporary. — Take two pieces of light 
 wire, strong enough to reach across the paper once, and throe or 
 four ])ieces of stout thread. Place one wire under tlie i)ni)('r as 
 far from the edge as yon choose to bind it. Put the threads 
 around the lower wire up through the paper, and tie them over 
 tlie other wire on toj). 'I'emporary covers of stiff ])asteb<)ard may 
 be added, liaving lioles for the reception of the thread, the wires 
 being placed on the outside of the cover. The successive papers 
 are, of course, to be threaded, one by one, by means of an awl or 
 coarse needle. 
 
 Oil-Cloths, Cleaning.— These should not bo washed with 
 soap. A coat of good copal varnish at long intervals improves 
 them. Oil-cloths sliould never bn scrubbed. Wipe with a wet 
 cloth, after brusliing with a soft floor- brush. 
 
 Oir.ED Floors.— Tli(! scrajyings from these should immediately 
 he placed in the open air. They are liable to sjiontaneous com- 
 bustion. 
 
HOUSEHOLD HINTS 241 
 
 Oil-Paintings, To restore old. — Take the painting out of tbe 
 frame, lay it on a table, face up, and keep a wet cloth on it for 
 two or three days, cliangiug or cleaning the cloth as often as it 
 becomes soiled. When the painting is clean, wash it with a 
 sponge or brush dipped in nut-oil. This is much better than 
 varnishing 
 
 Painter's Colic. — (1.) One drachm of sulphuric acid in 10 
 pints of table or spruce beer, or mild ale. Shake well, and allow 
 it to stand for a few hours. Take a tumlilerful twice or three 
 times daily. (2.) Make a beer of molasses, 14 lbs. ; bruised gin- 
 ger, ^ lb.; coriander-seed, i oz.; capsicum and cloves, i oz. each ; 
 water, 12i galls.; yeast, 1 pint. Put the yeast in last, and let it 
 ferment. When the fermentation has nearly ceased, add sul- 
 phuric acid, li OZ3., mixed with 12 ozs. water, and 14 ozs. bicar- 
 bonate of soda dissolved in water. It will be fit to drink in three 
 or four days. 
 
 Paint, To clean. — Dip a flannel rag into warm water, and wring 
 it out nearly dry. Take up on the rag as much whiting as will 
 adhere, and' rub this on the paint until the dirt or grease disap- 
 pears. Wash the part well with clean water, and rub dry with 
 soft chamois-skin. 
 
 Paint, To remove, from clothes. — Chloroform will remove 
 paint from a garment or elsewhere, when benzole or bisulphide 
 of carbon fails. 
 
 Paint, To remove old. — Slake 3 lbs. of stone quicklime in 
 water, and add 1 lb. American pearlash, making the whole into 
 the consistence of paint. Lay over the old work with a brush, 
 and let it remain for from 12 to 14 hours, when the paint is easily 
 scraped off. 
 
 Paper Comforters. — Two thicknesses of paper are better than 
 a pair of blankets, and much lighter for those who dislike heavy 
 bedclothes. A spread madt- of double layers of paper tacked to- 
 gether, between a covering of chintz or calico, is really a de- 
 sirable household article. Soft paper is the best, but newspapers 
 will answer. 
 
 Papering Walls. — Papering and painting are best done in 
 cold weather, especially the latter, for the wood absorbs the oil 
 of paii*t much more than in warm weather ; while in cold 
 weather the oil hardens on the outside, making a coat which 
 will protect the wood instead of soaking into it. Never paper a 
 wall over old paper and paste. Always scrape down thoroughly. 
 Old paper can be pot off by damping with saleratus and water. 
 Then go over all the cracks of the wall with plaster of Paris, 
 and, finally, put on a wash of a weak solution of carbolic acid. 
 The best paste is made out of rye-flour, with 2 ozs. glue dissolved 
 in 1 qt. paste ; \ oz. powdered borax improves the mixture. 
 
 Paste, A superior flour. — Thoroughly mix good clean flour 
 with cold water to a paste, then add boiling water, stirring up 
 well until it is of a consistence capable of being easily spread 
 with a brush. Add to this a little brown sugar, a little corrosive 
 sublimate, and about half a dozen drops of oil of lavender; 
 and keep, if convenient, two days before using. 
 
242 
 
 HOUSEHOLD HTXTS. 
 
 Petkoleum Bakkels. — These sliould not lie used to store food 
 3r drink in. They are poisonous even after being cleaned. 
 
 Plant-Case, A housetop or window. — A fernery or plant-case 
 niiorht he arranged to run the whole length of the front windows 
 of a story, and he heated by a small boiler placed behind a fire- 
 
 RECTIOX OF ri..\.NT-CAJiE. 
 
 place. From this a 2-inch flow and return ))ipe is taken 
 tlirougli the case, so as to heat it when rctpiired. The space 
 around the ])\\>ci^ can he lillcd with hark, or water if desirable, 
 .so as to ])roducf a moist and genial bottom lieat. The ferns, 
 mosses, and other decorative plants, are arranged in flat s(]uaro 
 pans of zinc or earthenware, as shown in our sectional sketch, 
 and the efTect of the whole, especially when sei-ii from within, 
 is very effective, and afTonls relief to tlie eye, which might 
 otherwise looii out f)n a dismal prospect of blackened roofs and 
 Hoof-begrinuHl cbininey-pots. 
 
 Pl,ANT8, Window, Cnre of. — Plants kept in the windows 
 should lie turned every ni'iniing, or the light, striking on one 
 side only, will draw the ])lant to thiif side, so that all its branches 
 and leaves will turn toward the wimlow. The water in the 
 saucers should never In- ap))lie(l to the plants. Fn cutting slips 
 
HOUSEHOLD HINTS. 243 
 
 of any plant, always choose the youngest branches ; and cut ofi 
 the sli)) at the junction of a joint or leaf, since the roots shoot 
 more readily from such joints. If you follow these directions, and 
 put sufficient sulphate of ammonia to just taint the water applied 
 to your plants, you may cultivate with success almost any plant, 
 even though you are an entire novice. 
 
 Plant-Cases, Wardian, Management of. — The following prin- 
 ciples are those upon which a fern-case should be constructed : 
 1. Have no apparatus or arrangement for drainage. 2. Make 
 your case as air-tight as possible, allowing for no ventilation. 
 
 Ferns require, tor their growth, shade and moisture : upon the 
 former, in a great degree, depends the latter. A northern or 
 eastern aspect, where the morning sun reaches the case, we tliink 
 is best. As regards moisture, we have the principle of self-sup- 
 port in an air-tight case ; for if you allow the sun to reach the 
 case for an hour or so in the morning, you will find that the 
 moisture needful for the growth of your ferns is extracted from 
 the earth ; and when evening comes, this same moisture will 
 condense and fall. Each day, this process of extraction and con- 
 densation takes place, and your plants flourish under a necessary 
 and sufficient moisture. Now, this being the kind of air we 
 want, we must not, of course, ventilate our case, and allow it to 
 escape, otherwise the dry air of our rooms would enter, and the 
 watering of the case become a necessity. This at once upsets all 
 the benefits derived from these cases. The temperature, also, 
 must be much more even in an air-tight case than in a ventilated 
 one, where the constant opening and shutting of doors and win- 
 dows would affect it. If we have no watering to do, we have no 
 water to run off", and consequently require no drainage in the hot 
 tom of our case. Now, in this air-tight principle, we get at the 
 secret. 
 
 In stocking Wardian cases, the amateur will find that almost 
 all ferns and mosses will do well in this case. There ^re few of 
 our greenhouse ferns that will not do well under this treatment ; 
 the gold and silver ferns are perhaps the exception ; they do not 
 always attain their full size and beauty in a Wardian case, but 
 the adiantums, pteris, polypodiums, blechnums, and others do 
 well. 
 
 In planting a case, do not place the plants too near, nor use 
 too many of a large size, but put in a few plants and of a mode- 
 rate size. Water well after setting the plants out. and shade the 
 case for a day or two ; then give it the morning sun each day 
 for an hour or two, and your ferns will soon start. Nothing can 
 be more interesting than to watch them — the frond pushes its 
 head above the earth, the heat and moisture of the case have 
 their effect, and it gradually rises and uncurls till it reaches its 
 height, then it expands into the most beautiful and giaceful of 
 shapes ; then what can exceed in delicacy and freshness this 
 newly-born part ? The lycopodiums grow finely, and spread very 
 rapidly in the case ; small pieces introduced at regular intervals in 
 the case will, in a marvelously short time, double their original size ; 
 and if the pendent roots of the creeping species are pressed well on 
 to the surface of the earth, the spaces between the plants and ferns 
 will soon be filled up, and a rich and delicate carpet be produced 
 
244 
 
 HOUSEHOLD HIXTS. 
 
 over the whole case. For climbers, nothing can give more satis- 
 faction th.a.njicusstiptdata, which can be obtained at all green- 
 houses. The roots of this plant, which strike out at every joint. 
 
 THE PltlNCESS OF WALES CASE. 
 
 have an adhesive power, and will attach themselves firmly to the 
 glass in the case, which renders the growth more rapid and regu- 
 lar. It is a very interesting plant to wutch ; the roots adhering 
 to the glass allow a free use of the nucroscope, and the growtli 
 and circulation can be studied to great advantage from the out- 
 side of the case. 
 
 TlIK ^VDKMIA.M I A^K. 
 
 Ah to soil, tlie brst mixture for tin- growth of ferns and 
 lycopodiuinH is the fnllDwiiig: lit-af mould, 2 parts; fresh 
 sanil, 1 ])urt ; gnivcl, about the sizr of a ]»t'a. 1 jiart ; and 
 stal)lc nuinure, clioppcd v«Ty fine, 1 part. Ferns whir-ji grow na- 
 turally in dry plares c-an be arranged on rock-work in the centre 
 
HOUSEHOLD HINTS. 245 
 
 of the case, if it is large enough to admit of it, and those re- 
 quiring more moisture should be placed nearer the sides of the 
 case, and they will get more moisture from the glass, where it 
 deposits in grer.t quantities. Tlie spores of ferns can be sown on 
 the surface of the earth in the Wardian case, and a constant sup- 
 ply of young plants can in this way be obtained, thus enabling 
 the student to watch them in every stage of development. 
 
 It happens that not un frequently the larvae of insects are in- 
 troduced in the earth into the case, and hatch out under the in- 
 fluence of the heat. To provide agahist this, it will be found 
 useful and interesting to put in a small-sized toad, and insects 
 will disappear very soon, and give no further trouble. Toads 
 will live through the winter perfectly well in this way, and their 
 habits can be studied ; some may become aware, by trying this 
 experiment, that the toad, although not one of the handsomest of 
 our reptiles, is not the least interesting. 
 
 Plants, Potting. — Those who find their efEorts to raise house- 
 plants frustrated by worms may be able to win success by boiling 
 the earth before setting the plants. Use little water, and allow 
 it to simmer away after a few minutes of hard boil. 
 
 Polish, Furniture. — Shave very fine white wax, 3 ozs., cas- 
 tile-soap, 1 oz. ; put the was in 1 gill turpentine, and let it stand 
 24 hours. Boil the soap in 1 gill water, and add to wax and tur- 
 pentine. 
 
 Potatoes, Saratoga, Fried. — The following is all there is of 
 the cook's secret for producing those w'orld-renowned potatoes 
 served at Moon's Lake House, Saratoga Spr ngs, every summer : 
 Peel good-sized potatoes, and slice them as evenly as possible ; 
 drop them into ice-water. Have a kettle of lard, as for fried 
 cakes, and veTj hot. Put a few at a time into a towel, shake 
 them about to dry them, and then drop into the hot lard. Stir 
 them occasionally ; and when of a light brown, take them out 
 with a skimmer. If properly done, they will not be at all greasy, 
 but crisp without, and mealy within. 
 
 Potatoes, Frozen. — These can be cured by soaking in water 3 
 days before cooking. 
 
 Rust-Spots, To remove from cloth. — Wet the spots of iron- 
 rust on muslin or white dress-goods thoroughly with lemon-juice, 
 then lay in the hot sun to dry. Repeat the same if the color is 
 not removed by one application. When dry, rinse in clear, cold 
 water. Lemon-juice can notbe used on colored goods, as it will 
 take out printed colors as well as stains. It will rernove all kinds 
 <'f stains from white goods. 
 
 Ring, To remove, when tight on the finger. — In case a finger- 
 ring becomes too tight to pass the joint of the finger, the finger 
 should first be held in cold water to reduce any swelling or infiam- 
 mation. Then wrap a rag soaked in hot water around the ring to 
 expand the metal, and lastly soap the finger. A needle threaded 
 with strong silk can then be passed between the ring and finger, 
 and a person holding the two ends and pulling the silk, while 
 sliding it around the periphery of the ring, will readily remove 
 the latter. Another method is to pass a piece of sewing-silk un- 
 
246 HOUSEHOLD HINTS. 
 
 der the ring, and wind the thread iu pretty close spirals aud close- 
 ly around the finger to the end — that below the ring — and begin 
 unwinding. 
 
 Rice, To boil. — The way they boil rice in India is as follows : 
 Into a saucei)au of 3 quarts water, when boiling, throw a table- 
 spoonful of salt ; then put in 1 pint rice, previously well washed 
 in cold water. Let it boil 20 minutes, throw out in a colander, 
 drain, and put back in tlie saucepan, which should be stood near 
 the fire for several minutes. 
 
 Rain- Water, To preserve sweet. — A drachm of pounded alum 
 to a gallon of water is sufficient. After 24 hours, the water will 
 be cleansed. All wooden vessels to hold water should be cliarred 
 inside. If a mixture in the proportion of ^ lb. of lime, made into 
 a paste, and added to a spoonful of powdered alum, be put into 200 
 gallons of water, it will soften the water, and precipitate vegeta- 
 ble and other matter. 
 
 -- Rats, Bait for. — Put a drop of rhodium oil on a bit of cheese or 
 meat. These animals detest chloride of lime and coal-tar. 
 
 , Rats, To catch. — Cover a common barrel with stifl' paper, tying 
 the edge around the barrel. Place a board so that the rats can 
 have easy access to the top. Sprinkle cheese or other bait on the 
 paper, and allow the rats to eat there unmolested for several days. 
 Then place in the bottom of the barrel a stone G or 7 inches high, 
 and pour in water until all the stone is covered, except for a space 
 about big enough for one rat to crawl upon. Now replace the 
 paper, first cutting a cross in the middle. The first rat that 
 ilimbs on the barrel-top goes through into the water, and 
 climbs on the stone. The paper comes back to its original posi- 
 tion, ami the second rat follows the first. Then begins a fight 
 for the possession of the dry place on the stone, the noise of whicli 
 attracts the others, who share the same fate. 
 
 Razors, Paper for sharpening. — By merely wiping the mzor on 
 the paper to remove the lather after shaving, a keen edge is main- 
 tained without further trouble. The razor must be well sharpen- 
 ed at the outset. First, procure oxide of iron (by the addition of 
 carbonate of soda to a solution of persulphate of iron), well wash 
 the j)recii)itate, and finally leave it of the consistence of cream. 
 Spread this over soft paper very thinly with a soft brush. Cut 
 the pa{)er in pieces two inches square, dry, and it is ready for 
 use. 
 
 RAZOK-STROr, To maki- a. — Select a piece of satin, maple, or 
 ro.se wimkI, 12 inches long, IJ inches wide, and findi thick ; allow 
 'Si inches for length of handle. Half an inch from where the 
 liandle begins, notch out the thickness of tin; leather so as to 
 make it flush toward the end. Taper also the thickness of the 
 leather; this precaulirjn i)revents the case from tearing up tlie 
 leather in putting the strop in. Tlicm round the wckmI very 
 slightly, just enough (say I'j of an inch) to keep from cutting by 
 the ruznr in stniijping and turiiiug over tin- same. Now select a 
 priiptT sizi-d |)ie(C()f fine French bookbinder's tiilfrtkiii, cover with 
 good whfut or ry<- paste, then lay the edge in tin- notch, and se- 
 cur.' it in place with a small vise, proceed to rul) it down firmly 
 
HOUSEHOLD HINTS. 247 
 
 and as solid as possible witli a tootli-brush handle (always at liand, 
 or should be), and, after the whole is thoroughly dry, trim it neat- 
 ly and make the case. 
 
 Sleeplessness, Cure for.— Mr. Frank Buckland says : " If I am 
 much pressed with work, and feel I shall not sleep, I eat two or 
 three small onions, and the effect is magical. Onions are also 
 excellent things to eat when much exposed to intense cold. In 
 salmon-fishing, common raw onions enable men to bear the ice 
 and cold of the semi-frozen water much better than spirits, beer, 
 etc. If a person can not sleep, it is because the blood is in his 
 brain, not in his stomach ; the remedy, therefore, is obvious : call 
 the blood down from the brain to the stomach. This is to be 
 done bv eating a biscuit, a hard-boiled egg, a bit of bread and 
 cheese," or something. Follow this up with a glass of wine or 
 milk, or even water, and you will fall asleep." 
 
 Smoked Meat, To preserve. — The keeping qualities of smoked 
 meat do not depend upon the amount of smoking, but upon the 
 uniform and proper drying of the meat. It is of considerable ad- 
 vantage also to roll the meat on its removal from the salt, before 
 smoki'ng, in sawdust or bran. By this means the crust formed in 
 smoking will not be so thick ; and if moisture condenses upon 
 the meat it remains in the bran, the brown coloring matter of the 
 smoke not penetrating. The best place to keep the meat is in a 
 smoke-house, in which it remains dry without drying out entirely, 
 as it does when hung in a chimney. 
 
 Spatter- Work Pictures. — These are delicate designs in white 
 appearing upon a softly-shaded ground. Procure a sheet of fine 
 uncalendered drawing-paper, and arrange thereon a bouquet of 
 pressed leaves, trailing vines, letters, or any design which it is de- 
 sired to have appear in white. Fasten the articles by pins stuck 
 into the smooth surface, which should be underneath the paper. 
 Then slightly wet the bristles of a tooth or other brush in rubbed 
 Indian ink, or in common black writing-ink. and draw them across 
 a stick in such a manner that the bristles will be bent and 
 then quickly released. This will cause a fine spatter of ink upon 
 the paper. Continue the spattering over all the leaves, pins, 
 and paper, allowing the centre of the pattern to receive the 
 most ink, the edges shading off. When done, remove the design, 
 and the forms will be found reproduced with accuracy on the 
 tinted ground. With a rustic wooden frame, this forms a very 
 cheap and pretty ornament. 
 
 Spoons, To remove stains on, caused by boiled eggs. — Rub 
 with common salt. 
 
 Sponges, Cleaning. — A gelatinous substance frequently forms 
 in sponges after prolonged use in water. A weak solution of 
 permanganate of potassa will remove it. The browm stain caused 
 by the chemical can begot rid of by soaking in very dilute muria- 
 tic acid. An old and dirty sponge may be cleaned by first soak- 
 ing it for some hours in a solution of permanganate of potassa, 
 then squeezing it, and putting it into a weak solution of hydro- 
 chloric acid, 1 part acid to 10 parts water. 
 
248 HOUSEHOLD HINTS. 
 
 Sponges, To bleach. — \Va;<li first in weak muriatic acid, then 
 in cold water ; noak in weak sul[iluuic acid, wash in water again, 
 and finally rinse in rose-water. 
 
 ^ Stains of Acid Fuuit, To remove, from the hands. — Wash 
 the hands in clear water, wipe them lightly, and while they are 
 yet moist, strike a match and shut your hands around it so as to 
 catch the smoke, and the stain will disappear. 
 
 Starch, To prevent souring when boiled. — Add a little sul- 
 phate of copper. 
 
 Stone, To remove moss from. — This is useful for the green 
 mould which forms on marble and brown stone steps. Apply a 
 solution of 75 grains ot carbolic acid to 1 quart of water. 
 
 Stoppers, Glass, To remove. — To move a tight glass stopper, 
 hold the neck of the bottle to a fiame, or take two turns of a string 
 and seesaw it. The heat engendered expands the neck of the 
 bottle before the expansion reaches the stopper. 
 
 Stove-IIolks in Walls. — See that these openings for the 
 pipes are protected by good tin covers alter the stoves are taken 
 down. Do not stuff rags in. 
 
 Straw MATTiN(i, Washing, — Use a cloth dampened in salt, 
 water. Indian meal sprinkled over it and thoroughly swept out 
 will also cleanse it finely. 
 
 Styptic Paper, for stopping the bleeding of small wounds. — 
 Mix gum benzoin (best quality), 1 lb.; rock alum, 1 lb.; water, 4^ 
 gals. Boil in a tin vessel for 4 hours, replacing the water lost by 
 evaporation. Saturate paper with the solution, dry carefully, and 
 brush over with a concentrated solution of perchloride of iron. 
 Keep in a water-proof and air-tight case. 
 
 Safk, Home-made fire-proof. — The best is a hole in the ground 
 well lined with brick and cement. 
 
 V SniHT-BosOMS, Glossing, — Take 2 ozs. of fine white gum-ara- 
 bic powder, put it in a jjitcher, and pour on a pint or more of wa- 
 ter, and then, having covered it, let it stand all night. In the 
 morning, pour it carefully from tln^ dregs intn a clean bottle, cork, 
 and keep it for use. A teaspoonful of gum-water stirred in a 
 l)int of starcli.made in the usual way, will giver to lawns, white 
 or printed, a lf>nk of newness when notliing else can risstore them, 
 after they have hft-n washed. 
 
 Shoes, Bronzing. — Black shoes may be bronzed by a strong 
 solution of aniline red in alcohol. 
 
 SifoKs, Black varnish for. — Take 10 parts, by weight, of shellac, 
 and ") of turpentine. Dissolve in 40 jiarts alcohol, in which fluid 
 should be previously dissolved 1 part extract of logwood, with 
 some- neutral diromate of potassa and snlphati^ of indigo. This 
 varnish is to be kipt in well-stopjiered bottles. 
 
 SiDKWALKS, Slii)i)ery. — Put on hot sand instead of ash(!B. 
 
 Silk, Washing. —Tlie way to wash silk is to spn^ad it Hinootlr 
 ly upon a cleiin lioaid, ml) whili^ soap ujjon it, ami brush it wit'i 
 a clean hand brush. 
 
 SiLVKIt, To chsan. — A strong solution of hyposulphite of soda is 
 uhhIuI for this puriM)H(;. 
 
HOUSEHOLD HINTS. 249 
 
 Silk, etc., To clean. — A teaspoouful of powdered borax dis- 
 solved in 1 qt. tepid water is good for cleaning old black dresses 
 of silk, cashmere, or alpaca. 
 
 Silver-Plate, To keep bright.— Warm the articles, and coat 
 carefully over with thin collodion diluted with alcohol, using a 
 wide soft brush for the purpose. 
 
 Sink-Spouts, To thaw frozen. — Place one end of a piece of lead 
 pipe against the ice to be thawed, and then through a funnel in 
 the upper end pour boiling water. Keep the pipe constantly 
 against the ice, and a foot or more per minute can be penetrated. 
 In order to thaw out water-pipes that become frozen and are inac- 
 cessible, the plan used by New-York plumbers is to surround 
 small india-rubber tubing with coiled wire so as to stiffen it and 
 admit of its being inserted far into the pipe. Tlu-ough the tube a 
 current of steam from a small boiler over a charcoal furnace is 
 allowed to pass. This acts very quickly, except when the pipe 
 takes a very irregular course, in which case there is no remedy ex- 
 cept to dig down into the earth or break out walls until the pipe 
 can be reached, and thawed by the direct application of heat. 
 
 Soap, Adulteration of, by starch.— This is detected by dissolv- 
 ing the soap in alcohol, which leaves the starch behind. 
 
 Soap, Gall, To make. — Gall soap, excellent for washing silks 
 and ribbons, may be made by heating 1 lb. cocoanut-oil to 60° 
 Fahr. , into which | lb. caustic soda is gradually stirred. To this 
 I lb. Venice turpentine, previously warmed in another vessel, is 
 added. The kettle is allowed to stand for four hours, subject to 
 a gentle heat, after which the fire is increased until the contents 
 are perfectly clear. One pound ox-gall, followed by 2 lbs. castile- 
 soap, is then mixed in, and the whole allowed to cool, when it 
 may be cut into cakes. 
 
 Soap, Habd, To prevent crumbling. — Dip the bars in a mixture 
 of resin-soap, beef-tallow, and wax. 
 
 Soap, Home-made. — Soap-making is not an easy process ; some- 
 times the ashes are poor, or the right proportions of lye and 
 grease are not used ; at other times the soap appears to be good 
 when put up, but changes entirely after standing a few days. 
 The last trouble usually arises from getting the soap too strong 
 and diluting with water. If very strong, it will be thin and dark ; 
 and by adding cold water and thoroughly stirring, the color is 
 changed many shades lighter and the mass thickened, giving it 
 the appearance of a No. 1 article, while in reality it is very poor. 
 Hickory-ashes are the best for soap-making, but those from sound 
 beach, maple, or almost any kind of hard wood except oak, will 
 answer Avell. A common barrel, set upon an inclined platform, 
 makes a very good leach ; but one made of boards set in a 
 trough in V-shape is better, for the strength of the ashes is better 
 obtained, and it may be taken to pieces when not in use, and put 
 away. First, in the bottom of the leach, put a few sticks ; over 
 them spread a piece of carpet or woolen cloth, which is much 
 better than straw ; put on a few inches of ashes, and then from 4 
 to 8 qts. lime ; fill with moistened ashes, and pack well down. 
 Pack the finest in the centre. It is difficult to obtain the full 
 strength of ashes in a barrel without removing them after a day's 
 
250 HOUSEHOLD HINTS. 
 
 leaching, and mixing tliem up and reitlacinii,-. Tlie top should be 
 first thrown (jff and new ashes added to make up the proper quan- 
 tity. Use boiling water for second leaching. Take about 4 gal- 
 lons lye, and boil up thoroughly with 12 lbs. clear grease, then 
 add the lye as it is obtained, keeping a slow tire and stirring often 
 until you have a barrel of soap. After boiling the grease and 4 
 gallons lye together, it may be put in a barrel and the rest of the 
 lye added there. This will form good soap if frequently stirred ; 
 but the heating process is the best, when weather and time will 
 permit. 
 
 Tattoo-Marks on the Skin, To remove. — Blister the part with 
 a plaster a little larger than the mark ; then keep the place open 
 for a week with an ointment ; finally, dress it to get well. As the 
 new skin grows, the tattoo-marks will disappear. 
 
 Tau-Spots, To remove. — Butter will remove tar-spots. Soap 
 and water will afterwaid take out the grease-stain. 
 
 Tea-Kettle, To prevent rust forming inside a. — Keep an oyster- 
 ' shell in the bottom of the kettle ; and when water is wanted, 
 pour off without agitating the vessel. Be careful also not to let 
 the water stand in the vessel when not in use. 
 
 Teeth, Extracting, Simple method of, for children. — The ope- 
 ration consists in simply slipping a rubber ring over the tooth and 
 forcing it gently under the edge of the gum. The patient is 
 then dismissed, and told not to remove the a])pendage, which in a 
 few days loosens the tooth, and causes it to fall out. 
 
 V Tin. Scouring. — Kerosene and powdered lime, whiting, or wood- 
 ashes, w-ill scour tins with the least labor. 
 
 vToothache — Saturate a bit of cotton wool in a strong solution 
 of ammonia, and apply it immediately to the affected tooth. 
 \^ Tubs and Pails, to prevent shrinking of. — Saturate with gly- 
 cerine. 
 
 Vegetables, To wash. — Vegetables should never be washed 
 until immediately before prepared for the table. Lettuce is made 
 alnir)st wortlilcss in liavor by (li])i)iiig it in water some hours be- 
 fore it is served, i'otatoes suff'cr even more than other vegetal)les 
 througli the washing [iroceas. They shoukl not be j)ut in water 
 till just ready for boiling. 
 
 Vkntilation ok Sleei'INO-Rooms, Simple ))lan for. — A ])iece 
 of wood ;{ ill. liigh, and exactly as long as the breadth of the 
 window, is to be ])r(!i)ared. Let the sasli l)e now raised, the slip 
 of wood placetl on the sill, and tlus sash drawn chjsely upon it. 
 If the slip has l)een w(!ll fitted, tliere will be no draft in conse- 
 <|iient'e of tliis displacement of the sash at its lower i)arl. ; but the 
 top of tlie lower sash will overlap the liottoni of tlie ii])per one, 
 and l)etw(;en tlie two bars prr]>en(liciil!ir currents of air, not felt 
 as draft, will enter and leave the room. 
 
 ViNEfiAH, 'i'o make, from molasHes. — Vinegar may be made by 
 mixing Ki ](arts pun^ water, 1 part syrup <>f molasses, and 1 part 
 baker's yeast at a temperature of al)out HO Kalir. , and k<^epingtlie 
 <-otnpoun<l in a warm atniosi)here from ten to thirty days. A 
 little old vinegar, udijed im tlie sei-oml or third il;iy, will aid the 
 proceHH, 
 
 I 
 
HOUSEHOLD HINTS. 251 
 
 Vinegar, Raspberry. — Pour over 1 lb. bruised berries, 1 qt. of 
 the best cider vinegar ; nextdsiy, strain the liquor on 1 lb. of fresh 
 ripe raspberries, bruise them also, and on the following day do 
 the same. Do not squeeze the fruit, only drain the liquor 
 thoroughly. Put the juice into a stone jar, and add sugar in pro- 
 portion of 1 lb. to a pint. When the sugar is melted, place the 
 jars in a saucepan of water, which heat ; skim the liqui>r, and 
 after it has simmered for a few minutes, remove from the fire, 
 cover, and bottle. 
 
 Washing-Elite. — Twenty lbs. white potato starch, 20 lbs. 
 wheat starch, 20 lbs. Prussian blue, 2 lbs. indigo carmine, and 2 lbs. 
 finely-ground gum-arabic are mixed in a trough, with the gradual 
 addition of sufficient water to form a half-fluid, homogeneous 
 mass, which is then poured out on a board with strips tacked to 
 the edges. It is then allowed to dry in a heated room until it 
 does not run together again when cut. It is next cat, by a 
 suitable cutter, into little cubes, and allowed to dry perfectly. 
 They are finished by lieing placed in a revolving drum, with a 
 suitable quantity of dry and finely pulverized Paris blue, until 
 they have a handsome appearance. The cost is about 12 cents 
 per pound. 
 
 V Washing Colored Fabrics. — Before washing almost any 
 colored fabrics, soak them in water, to each gallon of which a 
 spoonful of ox-gall has been added. A teacupful of lye in a pail 
 of water is said to improve the color of black goods. A strong 
 tea of common hay will improve the color of French linens. 
 Vinegar in the rinsing water, for pink and green, will brighten 
 those colors ; and soda answers the same end for both purple 
 and blue. 
 
 Wall-Paper, Removing stains on.'— Stains on wall-paper can 
 be cut out with a sharp penknife, and a piece of paper so nicely 
 inserted that no one can see tlie mtch. 
 
 Warts, Cure for. — Rubbing warts, night and morning, with a 
 moistened piece of nauriate of ammonia is said to cause their 
 disappearance without pain or a scar resulting. 
 
 H Water-Closets, Ventilating pipes for. — Extend pipes from 
 water-closet traps, or one (larger) from the main waste-pipe, into 
 the nearest chimneys. The pestilent gases will thus be carried 
 off instead of being allowed to escape into the house. 
 ^ Water, Hard, To soften. — Boil or add a small quantity of 
 quicklime mixed to a cream with water. 
 
 Water, To purify, from smoke. — Enough permanganate of 
 pota?sa is added to give the faintest possible tinge to the water. 
 After standing 24 hours, the impurities will all be precipitated. 
 ^^ Wounds, Cut. — A wound made by a knife or other sharp in- 
 strument is best healed by bringing the edges together and put- 
 ting on a bandage which "will not exclude the air. Nature will 
 work the cure, if the person be healthy, much better than anv 
 salve or ointment. 
 
 Water-Lilies, To raise.— Water-lilies may be raised about 
 one's house by the following method : Sink in the ground the 
 half of an old cask, and cover the bottom with peat and swamp 
 
252 HOUSEHOLP HINTS. 
 
 mud, and then fill witli water. Dig the lily roots early in the 
 spring, and place them in the earth at the bottom of the tub. 
 
 > Windows, Washing. — In washing windows, a narrow-bladed 
 wooden knite, sharply pointed, will take out the dust that hardens 
 in the corners of the sash. Dry whiting will polish the glass, 
 which should first be washed with weak black tea mixed with a 
 little alcohol. Save the tea-leaves for the purpose. 
 
 Wine, Preservation of, by heating. — Wine maj' be kept with- 
 out altering in quality for an indefinite period of time, in all 
 climates, after ha%'ing been first submitted to the action of artifi- 
 cial heat. The temperature to which it must be raised is from 
 131' to 140" Fahr. If the wine does not contain naturally more 
 than 10 or 12 per cent of alcohol, it is best to add li per cent 
 more before the shipping of it. The wine is to be heated by 
 steam and artificially cooled. 
 
 Yeast, Compressed. — Previously malted barley and rye are 
 ground up and mixed, next put into water at a temperature of 
 G5° to 75' ; after a few hours the saccharine liquid is decanted 
 from the dregs, and the clear liquid brought into a state of fer- 
 mentation by tlie aid of some yeast. The fermentation becomes 
 very strong ; and by the force of the carbonic acid which is 
 evolved, the yeast globules are carried to the surface of the 
 liquid, and, forming a thick scum, are removed by a skimmer, 
 then placed on cloth filters, drained, washed with a little distilled 
 water, and next pressed into any desired shape by means of 
 hydraulic pressure, and covered with a strong and well-woven 
 canvas. It keeps from 8 to 14 days, according to the season, and 
 is excellent. 
 
 Yeast for Hot Climates. — Boil 2 ozs. best hops in 4 qte. water 
 for A hour ; strain and cool to new-milk warmth. Put in ^ lb. 
 sugar, 1 tablf 'Spoonful of salt ; beat up 1 lb. of the best flour with 
 some of tht! liquor, and mix all well together. Let it stand for 3 
 days, and on the third day add 3 lbs. mashed and boiled jjota- 
 toes. On the next day, strain, and it is ready for use. This will 
 keep for 2 or 3 months in a moderately cool place. The yeast is 
 very strong ; half the usuiU quantity necessary for baking is 
 sufficient. 
 
 Yeast, Vienna. — Vienna bread and Vienna beer are said to be 
 the best in the world. Hoth owe their superiority to the yeast 
 used, which is ])rep»ro(l in the following nuinner : Indian corn, 
 barley, and rye (all sprouting) are powdered and mixed, and then 
 macfrated in water at a temperature of from 149' to Iti? Fahr. 
 Saccharification takes jilace in a few liours, when the liiiuor is 
 racked off and allowed to clear, and fermentation is set uj) by the 
 help of a minute quantity of any ordinary yeast. Carbonic acid 
 is disengaged during the process with so much rapidity that the 
 globules of yeast are thrown up by the gas, and remain floating 
 on the surface, where tiiey form a thick scum. Tlie latter is 
 carefully removed, and constitutes the best and purest yeast, 
 which, when drained and compressed in a liydraiilic press, can be 
 kei)t from H to 1.1 days, according to the season. 
 
s 
 
 •5J 
 
 
 AND 
 
 Mechanical Expert 
 
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 SPECIAL TOOLS, MACHINES i APPLIANCES 
 
 IVI^DE TO ORDER, 
 
 J\^eiv Manufcwtovies vut iiito covivlete worJdng 
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 Address, 
 
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RICHARD I BUEL, 
 
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 OFFERS HIS SERVICES TO 
 
 THOSE "WHO BUT l^OHnTERT, 
 To enable them to avoid costly mistakes ; 
 
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 To enable them by tests to prove the correctness of their guarantee ; 
 
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 suitable persons ; 
 
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SHELDON'S AUXILIARY 
 
 NJ 
 
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 A new Folding Stool, of strong and simple construction, easily attached 
 to the regular seats of street cars. Adds fifty per cent to the seating capacity 
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 When in use, as shown in engraving, does not interfere with people al- 
 ready seated, and when out of use can be folded entirely out of the way. 
 Compact, durable, and cheap. Equally well adapted to omnibuses, or for any 
 locality where temporary seats are needed. Patented Aug. 3d, 1875. 
 Address the inventor, 
 
 CEVEDRA B. SHEEI>OX, 
 
 No, 7 State Street, New-York City. 
 
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