THE f MOf lOAL IIOIMIIO COMPEISING A CLEAR EXPOSITION OF THE PRINCIPLES AND PRACTICE OF MECHANISM. WITH THEIK APPLICATION TO THE INDUSTRIAL ARTS. By J. A. DRAKE. PHILADELPHIA, PA.: J. W. LU K ENB AC H , Publisher. Price $2.50. Bound in Cloth. 1887 Entered, according to Act of Congress, in the year 1879, by J. W. LUKENBACH, in the Office of the Librarian of Congress, at Washington. PREFACE. ■jlTANY mechanical books arc obscured by theo- retical problems and complicated mathematical formulae, a defect which, it is believed, has been obviated in this volume, I trust my efforts will be duly appreciated by every " Practical Mechanic." THE AUTHOR. Definition of Arithmetical Signs used in the Work. = When we wish to state that one quantity or number is equal to another quantity or number, the sign of equaiity = is em- ployed. Thus 3 added to 2 = 5, or 3 added to 2 is equal to 5. 4- When the sum of two quantities or numbers is to be taken, the sign plus -{- is placed^ between them. Thus 3 + 2 = 5; that is, the sum of 3 and 2 is 5. This is the sign of Addition. — When the difference of two numbers or quantities is to be taken, the sign minus — is used, and shows that the latter num- ber or quantity is to be taken from the former. Thus 5 — 2 = 3. This is the sign of Subtraction. X When the product of any two numbers or quantities is to be taken, the sign into X is placed between them. Thus 3x2 = 6. This is the sign of Multiplication. -T- When we are to take the quotient of two quantities, the sign by -7- is placed between them, and shows that the former is to be divided by the latter. Thus 6-^2 = 3. This is the sign of Division. But in some cases in this work, the mode of division has been to place the dividend above a horizontal line, and the divisor below it, in the form of a vulgar fraction, thus: Dividend rv *• * ^ o T^. ■ = Quotient. x = 3. Divisor 2 When the square of any number or quantity is to be taken, this is denoted by placing a small figure 2 above it to the right. Thus 6- shows that the square of G is to be taken, and therefore 6- ^= 6 X 6 = 36. When we wish to show that the square root of any number or quantity is to be taken, this is denoted by i)lacing the radical sign v/ before it. Thus / 36 shows that the square root of 36 ought to be taken, hence y 36 = 6. The common marks of proportion are also used, viz., : : : : as 3 : 6 : : 4 : 8, being read 3 is to 6 as 4 is to 8 The application of these signs to the expression of rules is ex- ceedingly simple. Thus, connected with the circle we have the following rules: 1st. The circumference of a circle will be found by multiplying the diameter by 3.1416. 2d. The diameter of a circle may be found by dividing the cir- cumference by 3.1416. 3d The area of a circle may be found by multiplying the half of the diameter by the half of the circumference, or by inulti])lyiiig together the diameter and circumference, and dividing the pro- duct by 4, or by scjuaring the diameter and multiplying by .7854. Now all these rules may be thus expressed : Ist. diameter X 3. 1416 = circumference n^ circuinff'rence ^^ rTTTTT = diameter. 3 1110 3d. diameter circumference 2-X 2 = ""*• diameter X circumference or, . =area. 4 or, diameter" X • 7854 = area. THE PEACTICAL MECHANIC. A TABLE CONTAXNTNG THE DIAMETEES, CIECUMFERENCES, AND AEEAS OF CIRCLES, AXD THE CONTENTS OF EACH IN GALLONS AT 1 FOOT IN DEPTH UTILITY OF THE TABLE. EXAMPLES. 1. Eeqtiired the circumference of a circle, the diameter being five inches ? In the column of circumferences, opposite the given diameter, stands 15. 708 inches, the circumference required. 2. Kequired the capacity, in gallons, of a can, the diameter being 6 feet and depth 10 feet? In the fourth column from the given diameter stands 211.4472, being the contents of /i can 6 feet in diameter and 1 foot in depth, ■which being multiplied by ten gives the required contents, two thousand one hundred fourteen and a half gallons. 3. Any of the areas in feet multiplied by .03704, the product equals the number of cubic yards at 1 foot in depth. 4. The area of a circle in inches multiplied by the length or thickness in inches, and by .263, the product equals the weight in pounds of cast iron. 6 DIAMETERS AND CIRCUMFEREXCES OF CIRCLES. Diameters and Circumferences of Circles, and the Contents in Gallons at 1 Foot in Depth. Area in laches. Diam. Circ. iu.| Area in. Gallons. | Diam. Circ. in. Area in. 1 Gallons. 1 ia. 3.U1G' .7834 .04034 6 \ 20.420 33.183 1.72552 J. 3.5343 .9940 .05169 1 20.813 34.471 1.79219 3.9270 1.2271 .06380 s 21.205 35.784 1.86077 4 .1 4.3197] 1.4848 .07717 21.598 37.122 1.93034 5 4.7124 1.7671 .09188 7 in. 21.991 38.484 2.00117 1 5 1051 2.0739 .10784 i 22.383 39.871 2.07329 i 5.4978 2.4052 .12506 i 22.776 41.282 2.14666 5.8905 2.7G11 .14357 1 23.169 42.718 2.22134 2 in. G2832 3.1416 .16333 J 23.5G2 44.178 2.29726 6.6759 3.5465 .18439 r,. 23.954 4.5. 663 2.37448 7.0686 3.&7G0 .20675 24.347 47.173 2 45299 4 7.4613 4.4302 .23036 24.740 48.707 2.53276 8 7.8540 4.9087 .25522 8 in. 25.132 50.205 2.61378 8.24G7 5.4119 .28142 J 25.515 51.848 2.69609 a 8.6394 5.9395 .30883 O 25.918 53.4.56 2.77971 1 9.0321 6.4918 .33753 26.310 55.088 2.86458 3 in. 9.424S 7.0G86 .36754 ^ 26.703 56.745 2.95074 i ■ 9.8175 7.6699 .39879 £ 27.096 58.426 3.03815 10.210 8.2957 .43134 1 27.489 60.132 3.12686 10.602 8.9462 .46519 27.881 61.862 3.21682 ; • 10.995 9.6211 .50029 9ui. 28.274 G3.617 3.30808 11.388 10.320 •53664 1 2S.667 65.396 3 40059 » . 11.781 11.044 .57429 1 29.059 67.200 3.49440 ; , 12.173 11.793 .61324 29.452 69.029 3.58951 r 4 in. 12.566 12.566 .65343 1 29.845 70.882 3.08586 i 12.959 13.364 .69493 1 30.237 72.759 3.78317 13.351 14.186 .73767 1 30.630 74.662 3.88242 13.744 15.033 .78172 31.023 76.588 3.98258 14.137 15.904 .82701 10 in. 31.416 78.540 4.08408 14.529 16.800 .87360 J 31.808 80.515 4.18678 5 in. 14.922 17.720 .92144 1 32.201 82.516 4.29083 15.315 18.GG5 .97058 32.594 84 540 4. .39608 15.708 19.635 1.02102 1 32.9S6 86.590 4.50268 ■ 16.100 20.629 1.07271 1 33.379 88.664 4.61053 16.493 21.647 1.12564 i 33.772 90.7G2 4.71962 16.886 22.690 1.17988 1 34.164 92.885 4.82816 • 17.278 23.758 1.23512 11 in. 34.557 95.033 4.94172 17.671 24.850 1.29220 34.950 97.205 5.054G6 1 18.0t;4 25.967 1.35028 35.343 99.402 5.16800 f 18.457 27.108 1.40962 35.735 101.623 5.28139 in. 18.819 28.274 1.47025 36.128 103.869 5.40119 19.242 29.464 1.53213 ■ I 36.521 106.139 5.51923 I 10.635 30.679 1.59531 -.{ 36.913 103.434 5.03857 1 2 ).027 31.919 1.65979 i \ 37.30G 110.753 5.75916 DIAMETERS AND CIRCUMFEREXCES OF CIRCLES. [Area in Feet. ] Diam. Circ. Area in ft. Gallons. 1 Diam. Circ. 1 Are I in ft. Gallons. Ft. In. Ft In. 1 ft. depth, ft. In. Ft. In. 1 ft. depth. 3 1| .7854 5.8735 4 10 15 n 18.3476 137.2105 1 1 3 n .9217 6.8928! 4 11 15 H 18.9858 142.0582 1 2 3 8 1.0690 7.9944' 1 3 3 11 1.2271 9.1766 5 15 ^ 19.6350 146.8384 1 4 4 n 1.3962 10.4413 5 1 15 111 20.2917 151.7718 1 5 4 5| 1.5761 11.7866 5 2 16 2| 20.9656 156.7891 1 6 4 8.^ 1.7671 13.2150 5 3 16 5| 21.6475 161.8886 1 7 4 1^ 1.9689 14.7241 5 4 16 9 22.34' 167 0674 1 8 5 n 2.1816 16.3148 5 5 17 01 23.0137 172.3300 1 9 5 5} 2.4052 17.9870 5 6 17 H 23.7583 177.6740 1 10 5 9 2.6398 19.7414 5 7 17 4 24.4835 183 0973 1 11 6 n 2.8852 21.4830: 5 8 17 n 25.2199 188.6045 5 9 18 0| 25.9672 194.1930 2 6 H 3.1416 23.4940 5 10' 18 4 26.7251 199.8610 2 1 6 H 3.4087 25.4916 5 11 18 ''k 27.4943 2U5 6133 2 2 6 9i 3.6869 27.5720| 2 3 7 o« 3.9760 29.7340 6 18 10^ 28.2744 211.4472 2 4 7 3^ 4.2760 32.6976 6 3 19 7 30.6796 229.4342 2 5 7 7 4.5869 34.3027 6 6 20 4 33.1831 248.1564 2 6 7 101- 4.9087 36.7092! 6 9 21 4 35.7847 267.6122 2 7 8 n 5.2413 39.1964 o 2 8 8 M 5.5850 41.7668' 7 21 111 38.4846 287.8032 2 9 8 n 5.9395 44.4179 7 3 22 9? 41.2825 308.7270 2 10 8 lOi 6.3049 47.1505 7 6 23 4 44.1787 330.3859 2 11 9 U 6.6813 49.9654J 7 9 24 4 47.1730 352.7665 3 9 5 7.0686 52.8618 8 25 H 50.2656 375.9062 3 1 9 81 7.4666 55.8382 i 8 3 25 11 53.4562 399.7668 3 2 9 m 7.8757 58 -8976'! 8 6 26 81 56.7451 424.3625 3 3 10 '^ 8.2957 62.0386 S 9 27 4 60.1321 449.2118 3 4 10 5§ 8.7265 65.2602 1 3 5 10 8| 9.1683 68.5193 9 28 31- 63.6174 475.7563 3 6 10 Hi 9.6211 73.1504 9 3 29 o| 67.2007 502.5536 3 7 11 3 10.0846 75.4166 9 6 29 104 70.8823 530.0861 3 8 11 6^ 10.5591 78.9652 9 9 30 7i 74.6620 558.3522 3 9 11 ^i 11.0446 82.5959 it 3 10 12 5.t 11.5409 86.3074 10 31 5 78.5400 587.3534 3 11 12 3i 12.0481 90.10J4 10 3 32 21 82.5160 617.0876 10 6 32 Hi' 86.5903 647.5568 4 12 6| 12.5664 93.9754 :10 9 33 91 90.7627 678.2797 4 1 12 n 13.0952 97.931011 34 61 95.0334' 710.6977 4 2 13 1 13.635:J 101.9701 it; 3 35 8 U 99.4021 743.3686 4 3 13 n 14.1862 103.0300' 111 6 36 103.8691 776.7746 4 4 13 n 14 7479 110.2907 11 9 36 2 lOi 108.4342 810.9143 4 5 13 IOa 15.3206 114.5735 j.-^ 8 4 6 14 15.9043 118.9386, |12 37 8| 113.0976 848.1890 4 7 14 16.4986 123.3830 12 3 J8 5t 117.8590 881.3966 4 8 14 7i 17.104^ 127.9112 12 6 39 3| 122.7187 917.7395 4 9 14 11 17.7215 132.5209' 12 9 10 Of 127.6765 954 8159 DIAMETERS AND CIRCUMrERE2>'CES OF CIRCLES. Diameters and Circumferences of Circles, and the Contents in Gallons at 1 Foot in 'Depth.— {Cont'd.) [Area in Fevt.l Ciam. Circ. Area iu ft Gallons. Diani. Circ. Area ill ft. Gallons. Ft. la. Ft. In. 1 ft. depth. Ft. In Ft. In. 1 ft. depth. 13 4'J 10 132.732G 992.6J74 22 69 If 380.1336 2842.7910 13 3 41 7^ 137.88G7, 1031.1719 22 3 69 lOi^ 388.8220 2907.7664 13 6 t2 ^ 143.1391 10711.4514 22 670 8i 397.6087 2973.4889 13 9 43 2i U.S. 4896 1108.0645 22 9 71 5s 406.4935 3039.9209 11 43 llj 153 9384 1151.2129 23 72 3 415.4766 3107.1001 14 3 44 n 159.48.32 1192.6940 23 3 73 OJ 424.5577 3175.0122 14 G 45 H 165.1303 1234.9104 23 6 73 91 433.7371 3243.6595 14 9 16 4 170,8735 1277.8615 23 9 74 71 443.0146 3313.0403 15 47 li 176.7150 1321.5454 24 75 n 452.3904 3383.1563 15 3 17 104 182.6545 1365.9634 24 3 76 4 461.8642 3454.0051 15 G 4S H 188.G923 1407.5165 24 6 76 111 471.4363 3525.5929 15 9 49 5;i 194.8282 1457.0032 21 9 77 9 481.1005 3597. 90G8 16 50 3J 201.0624 1503.6250 25 78 Gl 490.8750 3670.9596 IG 3 51 0.1 207.3916 1550.9797 25 3|79 31 5')0.7415 3744.7452 IG G 51 10" 213.8251 1.')9'.).0696 25 6'80 i; 510.7063 3819.2657 IG 9 52 7'' '8 220.3537 1647,8930 25 9 80 lOil 520.7692 3894.5203 17 53 4^ 226.9806 1697.4516 26 81 8 J 530.9304 3970.5098 17 3 54 n 233.7055 1747.7431 26 3 82 51 541.1896 4047.2322 17 G 54 111 240.5287 179S.7698 26 61,83 3 1551.5471 4 124.6898 17 9 55 247.4500 1850.5301 26 9|84 02 562.0027 "1 4202.9610 18 5G ^ 2r,4.4696 1903.0254 27 84 9; .572.5566 4281.8072 18 3 57 4 261.. 5872 19.56.2537 27 3!85 8i 583. 2085,4361.4664 18 6' 58 13 268.8031 2010.2171 27 686 4| 593. 9.58714441. 8G07 18 9 53 io| 276.1171 2061.9140 27 9!87 2i 604.8070 4522.9886 1 19 59 ^ 28.3.5294 2120.3462 28 S7 lU 615.7536 4604.8517 19 3 GO n 291 0397 2176.5113 28 3 88 9' 620.7982 46K6.4S76 19 6GI 29S,64S3 2233.2914 28 6 89 62 637.9411 3^649.1821 4770.7787 19 9C2 Oi 306 3550 2291.0152 28 9 99 4854.8434 20 G2 9J 3 U. 1600 2349.4141 29 91 11 G60.52H 10 671.9587 4939. G432 20 3G3 \ 322.06 51) 210s. 5 1.59 29 3 91 502.5.1759 20 G G4 2 3:j().0(;i3 2168.3.528 29 (; 92 8| (;83.4943 5111.4487 21) 9 G5 1 338.1637 2528.9233 29 9 93 5^695.1280 5198.4451 21 65 lie .346.3614 2590.2290 30 94 2 J 706.8600 528G.1818 21 3!G6 9 351.6571 2652. 2.532 30 3 95 03 7 18. ('.900 .5374.6512 21 CG7 i\ .363.0511 27150413 30 C:9.) 9{ 730.6183 5463.85.58 21 9G8 371.5132 2778. .5486 30 9!9G 7(742 6447 55,53.7940 CONTENTS OP FEUSTUM OF A CONE. 9 Contents in Gallons of the Frustum of a Cone. To find the Contents in Gallons of a Vessel whose diameter is larger at one end than the other, such as a Bowl, Pail, Firkin, Tub, Coflfee-pot, &c. Rule. — Multiply the larger diameter by the smaller, and to the product add one-third of the square of their difference, multiply by the height, and multiply that product by .0034 for Wine Gal- lons and by .002785 for Beer. Example. —Required the contents of a Coffee-pot 6 inches di- ameter at the top, 9 inches at the bottom, and 18 inches high. Large diameter 9 Small do. 6 54 ^ of the square 3 57 height 18 456 57 Brought up 1026 .0034 4104 3078 3.4884 AVine Gallons, or nearly 3i gallons. Carried up 1026 1026 multiplied by .002785 equal 2.8574 JJter Gallons. Kule to find the Contents in Gallons of any Square Vessel. Rule. — Take the dimensions in inches and decimal parts of an inch, multiply the length, breadth, and height together, and then multiply the product by .004329 for Wine Gallons, and by .003546 for Ale Gallons. Example. — How many Wine Gallons will a box contain that is 10 feet long, 5 feet wide, and 4 feet deep ? Length in inches. Breadth in do. Height in inches, 120 60 Brought up 345600 .004329 7200 48 3110400 691200 1036800 1382400 57600 28800 1496.102400 gallons, or 1496 galls, and 3^ gills. 345600 10 CONTENTS IN GALLONS OF CYLINDRICA], VESSELS. Contents in Gallons of Cylindrical Vessels. Rule. — Take the dimensions in inches and decimal jiartsof an inch. Square the diameter, miiltiply it by the length in inches, and then multiply the product by .0034 for Wine Gallons, or by .002785 for Ale Gallons. Example. — How many U. S. Gallons will a Cylindrical Vessel contain, whose diameter is 9 inches and length 9^ inches? Diameter, 9 Brought up 769.5 9 .0034 Square Diam. Si Length, 9.5 30780 23085 405 729 2.G1630 or 2 gallons and 5 pints Carried up 7G9.5 To ascertain the Weights of Pipes of Various Metals, and any Diameter required. Thickness iu l«arts of nil Wrought Iron. Copper. Lead. inch. 1-32 .320 lU lbs. plate .38 2 1bH . lead .483 1-lG .053 23 i " -.70 4 .9G7 3-32 .97G 35' " 1.14 ^ 1.45 1-8 1.3 iCk " 1.52 8 1.933 5-32 1.G27 58 " 1 9 9.V 2.417 3-1 G 1.95 70 " 2.28 11 2.9 7-32 2.277 80 J " 2.GG 13 3.383 1-4 2.6 93 " 3.04 15 3.8G7 Rule. — To the interior diameter of tho pipe, in inches, add the tliicknesH of the metal; multiply the sum by the decimal num- bers opposite the re(piired tliieloiesH and under the metal's name; also by the length of tho pipe in feet, and tho product is the wiight of tho jiipo in lbs. 1. Rcrpiired tho weiglit of a cojijxt iiipo whoso interior diam- eter is 7.^ inches, its length (>] foet, and the metal j^ of an inch in thickness. 7.5 -(- .121 -^ 7.G25 X 152 X G.25 = 72.4 lbs. 2. What is tho weight of a lead(!n i)ipo IH.l feet in length, 3 inches interior diameter, and the metal ', of an inch in thickness? 3 -f .25 ^ 3.25 X 3.8G7 X 1H.5 = 232.5 lbs. WEIGHT OF WATER AND DECIMAL EQUIVALENTS. 11 Weight of Water. 1 Cubic inch equal to .03G17 pound. 12 Cubic inches equ.nl to .431 pound. 1 Cubic foot equal to G2.5 pounds. 1 Cubic foot equal to 7.50 U. S. gallons. ■1.8 Cubic feet equal to 112.00 povmds. 35.84 Cubic feet equal to 2240.00 pounds. 1 Cylindrical inch equal to .02842 pound. 12 Cylindrical inches equal to . 341 pound. 1 Cylindrical foot equal to 49.10 pounds. 1 Cylindrical foot equal to G.OO U. S. gallons. 2.282 Cylindrical feet ...equal to 112.00 pounds. 45.64 Cylindrical feet equal to 2240.00 poimds. 11.2 Imperial gallons equal to 1 12.00 pounds. 224 Imperial gallons equal to 2240.00 pounds. 13.44 United States galls equal to 112.00 pounds. 268.8 United States galls equal to 2240.00 pounds. Centre of pressure is at two-thirds depth from surface. Decimal Equivalents to the Fractional Parts of a Gallon, or an Inch. {The Inch, or Gallon, being divided into 32 pa?'/s.] [In multiplying decimals it is usual to drop all but the first two or three figures J . Gallon. 1 Gallon, w Gallon. m Deci- or 3 00 ' Deci- or m Deci- or :S n aa mals. Inch 1 s 1 1 mals. Inch. 3-8 12 3 mals. Inch. O 23 54 O" .03125 1-32 .375 .71875 23-32 2J .0G25 1-16 2 1 4 .4062") 13-32 13 3i 1^ .75 3-4 24 6 3 .09375 3-32 3 1 ? 4375 7-16 14 U 11 .78125 25-32 25 64 34 .125 1-8 4 1 4 46875 15-32 15 3i n .8125 13-16 26 dk 34 .15625 5-32 5 u i .5 1-2 16 4 2 .84375 27-32 27 H Si .1875 3-16 6 u 1 .53125 17-32 17 H 2f .875 7-8 28 7 3S .21875 7-32 7 H 7 s .5625 9-16 18 M 24 .90625 29-32 29 74 31 .25 1-4 8 2 1 .59375 19-32 19 n n .9375 1.5-16 30 7.^^ .28125 9-32 9 24 u .625 5-8 20 5 24 96875 31-32 31 74;3J .3125 5-16 10 ■u l.i .65625 21-32 21 54 2S 1.000 1 32 8 4 .31375 11-32 11 n li .6875 11-16 22 H 24 Application. —Required the gallons in any Cylindrical Vessel. Suppose a vessel 9.} inches dee]5, 9 inches diameter, and contents 2.6163, that is, 2 gallons and 61 hundredth parts of a gallon; now to ascertain this decimal of a gallon, refer to the above Table for the decimal that is nearest, which is .625, opposite to which is 5-8ths of a gallon, or 20 gills, or 5 pints, or 2 J quai'ts, consequently the vessel contains 2 gallons and 5 pints. Inches. — To find what part of an inch the decimal .708 is. Refer to the above Table for the decimal that is nearest, which is .71875, opj)osite to which is 23-32, or nearly 3-4ths of an inch. 12 TIN PLATES. Tin Plates. Size, Length, Breadth, and Weight. No. of Length and Weiebt per Bkand Mars. Sheets in Box. Breadth. ] Box Inches. Cwt .qv lbs. 1 C 225 14 by 10 1 " 1 X 225 14 by 10 1 1 1 XX 1 XXX 1 xxxx 225 225 225 14 by 10 14 by 10 14 by 10 1 1 1 1 2 3 21 14 7 Each 1 x advances $1.75 to $2.00. 1 xxxxx 225 14 by 10 2 1 xxxxxx 225 14 by 10 2 21 , D C 100 17 by VZh 3 14 a3 IK O 00 D X D XX lOD 100 17 by 121 17 by 121 1 1 1 14 7 f siz pose Q pr re e D XXX 100 17 by 12.i 1 2 D xxxx 100 17 by 121 1 2 21 D xxxxx D xxxxxx 100 100 17 bv I'i.i 17 by 12i 1 2 3 14 7 .S CO •' o oj is S D C 200 15 by 11 1 1 27 c: C^ii a> CO S D X 200 15 by 11 1 2 20 tCgc.|-5 S D XX 200 15 by 11 1 3 13 a .S fl-S c -7- .C S P S 1> XXX 200 15 by 11 2 C S D XXXX 200 15 by 11 2 27 S 1) xxxxx S D xxxxxx 200 2U0 15 by 11 15 by 11 2 1 20 2 2 13 about In add impoi ually c rtion imed r TTT Taggers, 225 14 by 10 1 .2sa^ 1 C 225 12 by 12 1 X 225 12 by 12 1 XX 225 12 by 12 1 1 XXX 2?5 12 by 12 About the same 1 xxxx 225 12 by 12 . weight ])tr Box as [■ the jilates above 1 c 112 11 by 20 of similar brand, 1 x 112 14 bv 20 M by 10. 1 XX 112 1 1 bv 20 1 XXX 112 11 bV 21) 1 XXXX 112 11 by 20 Letuhd or \ 1 C 112 14 by 20 1 [ For llmfing. Tenics f 1 x 112 14 by 20 1 1 MENSURATION. 13 Oil Canisters {frcm 2.} to 125 galls.), with the Quantity and Quality of Tin required for Custom Work. Galls. Quantity and Quality. Galls. Quantity and Quality. ^ 8 10 15 2 Plates, I X in body, 2 " SDX 2 " DX 4 " IX 3^ " DX 4 " DX 33 45 60 90 125 13^ Plates, IX in body, 3 breadths high. 1 3i Plates, SDXin body. 13^ " DX " \b\ " DX " * 20 " DX " * The bottom tier of plates to be placed lengthwise. MENSURATION. Of the Circle, Cylinder, Sphere, &c. 1. The circle contains a greater area than any other plane figure bounded by an equal perimeter or outline. 2. The areas of circles are to each other as the squares of their diameters. 3. The diameter of a circle being 1, its circumference equals 3.1416. 4 The diameter of a circle is equal to .31831 of its circumfer- ence. 5. The square of the diameter of a circle being 1, its area equals .7854. 6. The square root of the area of a circle, multiplied by 1. 12837, equaLs its diameter. 7. The diameter of a circle multiplied by .8802, or the circum- ference multiplied by .2821, equals the side of a square of equal area. 8. The sum of the squares of half the chord and versed sine divided by the versed sine, the quotient equals the diameter of corresponding circle. 9. The chord of the whole arc of a circle taken from eight times the chord of half the arc, one-third of the remainder equals the length of the arc; or, 10. The number of degrees contained in the arc of a circle, multiplied by the diameter of the circle and by .008727, the pro- duct equals the length of the arc in equal terms of unity. 11. The length of the arc of a sector of a circle multiplied by its radius, equals twice the area of the sector. 12. The area of the segment of a circle equals the area of the sector, minus the area of a triangle whose vertex is the centre, and whose base equals the chord of the segment; or. 14 MENSURATION. 13. The area of a segment may be obtainetl by dividing the height of the segment by the diameter of the circle, and multiply- ing the corresponding tabular area by the square of the diameter. 14. The sum of the diameters of two concentric circles, miilti- plied by their diflerence and by .7854, equals the area of the ring or space contained between them. 15. The sum of the thickness and internal diameter of a cylin- dric ring, multi])lied by the square of its thickness and by 2.4G74, equals its solidity. 16. The circumference of a cylinder, multiplied by its length or height, equals its convex surface. 17. The area of the end of a cylinder, multiplied bj' its length, equals its solid contents. 18. The area of the internal diameter of a cylinder, multiplied by its depth, ecpials its cubical cajiacity. 19. The square of the diameter of a cylinder, multiplied by its length and divided by any other reqiiired length, tlie scpiare root of the quotient equals the diameter of the other cylinder of equal contents or capacity. 20. The square of the diameter of a sphi're, multiplied by 3.1416, equals its convex surface. 21. The cube of the diameter of a sphere, multiplied by .5236, equals its solid contents. 22. The height of any spherical segment or zone, multiplied by the diameter of the sphere of which it is a part, and by 3.1416, equals the area or convtx surface of the segment; or, 23. The height of the segment, multiplii.'d by the circumfer- ence of the sphere of which it is a part, equals the area. 24. The solidity of any spherical segment is equal to three times the square of the radius c>f its base, plus the sqxiare of its height, and multiplied by its height and by .5236. 25. The solidity of a spherical zone e02 150 30 'I'lu^ tabular area of the corrcKiMiTiding jiolygnii, muKiplied by the square tif tlie side of llie given polygon, equals the. area of the given i)olygon. Of Ellipses, Cones, Frustums, &c. 1. Th«) Kijuiirc root of half the sum of the Kijuares of iiinieterH of an ellipso, multiplied by 3.1410, (Miuals its d ferenco, the two circum- INSTRUMENTAL ARITHMETIC. 17 2. Tlie prodxict of the two axes of an ellipse, multiplied by .7854, equals its area. 3. The curve surface of a cone is equal to half the product of the circumference of its base multiplied by its slant side, to which, if the area of the base be added, the sum is the whole surface. 4. The solidity of a cone equals one-third of the product of its base multiplied by its altitude or height. 5. The squares of the diameters of the two ends of the frustum of a cone added to the product of the two diameters, and that sum multiplied by its height and by .2618, equals its solidity. INSTRUMENTAL AKITHMfeTIC, Or Utility of the Slide Rule. The slide rule is an instrument by which the greater portion of operations in arithmetic and mensuration may be advantage- ously performed, provided the lines of division and gauge points be made properly correct, and their several values familiarly un- derstood. The lines of division are distingnishe d by the letters a b c d; A. B and c being each divided alike, and containing what is termed a double radius, or double series of logarithmic ntxmbers, each series being supposed to be divided into 1,000 equal parts, and distributed along the radius in the following manner: From 1 to 2 contains 301 of those parts, being the log. of 2. " 3 " 477 " " 3, 4 " 602 " " 4. 5 " 699 " " 5, " 6 " 778 " " 6. " 7 " 845 " " 7. 8 " 903 " " ' 8. 9 " 954 " " 9. 1,000 being the whole number. The line d on the improved rules consists of only a single ra- diias; and although of larger radiiis, the logarithmic series is the same, and disposed of along the line in a similar proportion, forming exactly a line of square roots to the numbers on the lines B c. Numeration. Numeration teaches us to estimate or i^roperly value the num- bers and divisions on the rule in an arithmetical form. Their values are all entirely governed by the value set upon the first figure, and, being decimally reckoned, advance tenfold from the commencement to the termination of each radius: thus, suppose 1 at the joint be one, the 1 in the middle of the rule is 18 INSTRUMENTAL ARITHMETIC. ten, and 1 at the end, one hundred ; again, suppose 1 al the joint ten, 1 in the middle is 100, and 1 or ten at the end is 1,000, &c., the intermediate divisions on which completes the whole system of its notation. To Multiply Numbers by the Hule. Set 1 on B opposite to the multiplier on a; and against the num- ber to be multiplied on b is the product on a. Multiply 6 by 4. Set 1 on B to 4 on a; and against G on b is 24 on a. The slide thiis set, against 7 on b is 28 on a. 8 " 32 " 9 " 3fi " 10 " 40 " 12 " 48 " 15 " GO " 25 " 100 " &c. To Divide Numbers upon the Rule. Set the divisor on b to 1 on a ; and against the number to be divided on b is the quotient on a. Divide 63 by 3. Set 3 on n to 1 on a; and against 63 ou b is 21 on a. Proportion, or Rule of Three Direct. Rule. — Sit the first term on b to the second on a; and against the third upon b is the fourth uj^on a. 1. If 4 yards of cloth cost 38 cents, what will 30 yards cost at the same rate ? Set 4 on b to 38 on a; and against 30 on n is 285 cents on a. 2. Suj)j)os<; I pay 31 dollars 50 cents for 3 cwt. of copper, at what rate is tliat jx-r ton? 1 /o?( ,=; 20 net. Set 3 upon b to 31.5 upon a; and against 20 upon n is 210 upon a. Rule of Three Inverse. Rule. — Invert the sliile, and the operation is the same as direct proportion. 1. I know that six men are capabh' of pcrforiuing a certain given portion of work in ou a; uud against 20 upon c is 10 upon A. INSTRUMENTAL ARITHMETIC. 19 3. If 8| yards of cloth, 1 J yards in width, be a sufficient quan- tity, how much will be required of that which is only 7-8th3 in width, to effect the same purpose? Set 1.5 upon c to 8.75 upon a; and against 8.75 upon c is 15 yards upon a. Square and Cube Boots of Numbers. On the engineer's rule, when the lines c and d are equal at both ends, c is a table of squares, and d a table of roots, as Squares 1 4 9 16 25 36 49 64 81 on c. Boots 12 3 4 5 6 7 8 9 on d. To find the Geometrical Mean Proportion between two Numbers. Set one of the numbers upon c to the same niimber upon d; and against the other number upon c is the mean number or side of an equal square upon d. Required the mean proportion between 20 and 45. Set 20 upon c to 20 upon d; and against 45 upon c is 30 upon d. To cube any number, set the number upon c to 1 or 10 upon d; and against the same number upon d is the cube number upon c. Required the cube of 4. Set 4 upon c to 1 or 10 upon d; and against 4 upon d is 64 upon c. To extract the cube root of any number, invert the slide and set the number upon b to 1 or 10 upon d; and where two num- bers of equal value coincide on the lines b d is the root of the given number. Required the cube root of 64. Set 64 upon b to 1 or 10 upon d; and against 4 upon b is 4 upon D, or root of the given number. On the common rule, when 1 in the middle of the line c is set opposite to 10 on d, then c is a table of squares, and d a table of roots. To cube any niimber bj^ this rule, set the number upon c to 10 upon n; and against the same number upon d is the cube upon c. Mensuration of Surface. 1. Squares, Rectangles, ; then will the lines c and D be a table of areas and diameters. Areas 3.14 7.06 12.56 19.63 28.27 38.48 50.26 63.61 upon c. Diam. 2 3456789 upon d. In the common rule, set .7854 on c to 10 on n; then c is a line or table of areas, and n of diameters, as before. Set 7 upon b to 22 ujjon a; then b and a form or become a table of diameters and circumferences of circles. Cir. 3.14 6.28 9.42 12.56 15.7 18.85 22 25.13 28.27 upon a. I>ia. 123 4 56 78 9 upon b. Polygons from 3 to 12 Sides.-^et the gauge-point upon c to 1 or 10 upon v; and against the length of one side upon D is the area upon c. Sides 3 5 6 7 8 9 10 11 12 Gauge-points .433 1.7 2.6 3.63 4.82 6.18 7.69 9.37 11.17 Required the area of an equilateral triangle, each side 12 inches in length. Set .433 upon c to 1 upon n; and against 12 ujwn d are 62.5 square inches upon c. Table of Gauge-Points for the Engineer's Rule. Names. F, F, F. F, I, I. I, I, I. F, I. I, I. F. I. Cubic inches. . 578 83 1728 106 1273 105 121 Cubic feet .... 1 144 1 1833 22 121 33 Imp. gallons. . 163 231 277 294 353 306 529 Watfr in lbs. . 16 23 270 293 352 305 528 Gold 814 1175 141 149 178 155 269 Silver " 15 216 261 276 334 286 5 Mercury " lis 109 203 216 258 225 3H9 JJrass 193 177 333 354 424 3(;9 637 CopJXT " 18 26 319 331 397 345 596 Lwnl 141 203 243 258 31 27 465 Wro't iron " 207 297 357 338 453 394 682 Cast ircju " 222 32 3HI 407 4H9 421 733 Tin 219 315 378 401 481 419 728 Strcl 202 292 352 372 418 385 671 Coal 127 1H3 22 33 28 242 42 Miirbl.) 591 85 102 116 13 113 195 Froehtono " • G32 015 11 1102 14 141 21 <» INSTRUMENTAL ARITHMETIC. 21 For the Common Slide Riile. Names. F, F, F. F, I, I. I, I, I. F, I. 1,1. F. I. Cubic inches. 36 618 624 669 799 625 113 Cubic feet .... G25 9 108 114 138 119 206 Water in lbs. . 10 144 174 184 22 191 329 Gold 507 735 88 96 118 939 180 Silver 938 136 157 173 208 173 354 Mercury " 738 122 127 132 162 141 242 Brass ' ' 12 174 207 221 265 23 397 Copper " 112 163 196 207 247 214 371 Lead " 880 126 152 162 194 169 289 Wro't iron " 129 186 222 235 283 247 423 Cast iron " 139 2 241 254 304 265 458 Tin 137 135 235 25 300 261 454 Steel 136 183 22 233 278 239 418 Coal 795 114 138 116 176 151 262 Marble " 370 53 637 725 81 72 121 Freestone " 394 57 69 728 873 755 132 Mensuration of Solidity and Capacity. General Eule. — Set the length upon b to the gauge-point upon a; and against the side of the square, or diameter on d, are the cubic contents, or weight in lbs. on c. 1. Required the cubic contents of a tree, 30 feet in length and 10 inches quarter girt. Set 30 upon b to 144 (the gauge-point) upon a; and against 10 upon D is 20. 75 feet upon c. 2. In a cylinder, 9 inches in length and 7 inches diameter, how many cubic inches? Set 9 upon b to 1273 i^tlie gauge-point) upon a; and against 7 on D is 346 inches on c. 3. ^liat is the M-eight of a bar of cast iron, 3 inches square and 6 feet long ? Set 6 upon b to 32 (the gauge-point) upon a; and against 3 upon D is 16S pounds i;pon c. By the Common Rule. 4. Required the weight of a cylinder of wrought iron, 10 inches long and 5^ diameter. Set 1!) upon B to" 283 (the gauge-point) upon a; and against 5^ upon D is 66.63 pounds on c. 5. What is the weight of a dry rope, 25 yards long and 4 inches circumference ? Set 25 upon b to 47 (the gauge-point) upon a; and against 4 on D is 53. 16 pounds on c. 6. What is the weight of a short-linked chain, 30 yards in length and 6-16ths of an inch in diameter? Set 30 upon b to 52 (the gauge-point) upon a; and against C on D is 129.5 pounds on c. 22 MANUFACTURE OF TIX PLATE. Power of Steam-Engines. Condensing Engines. IIole — Set 3.5 on c to 10 on d; then n is a line of diamt'ters for cylinders, and c the corresjiond- ing number of horses' power; thus, H. rr. 3.\ d 5 6 8 10 1-2 16 20 25 30 40 50 on c. CD. 10 in. 10^- 12 U\ 15.^ 17 18J 2U 24 26^ 29i 33| 37|onD. The same is eflfected on the common riile by setting 5 on c to 12 on D. Non-Condetiaing Engines. ErnE. — Set the jiressure of steam in pounds per S(juarc inch on b to 4 upon a; and against the cylinder's diameter on n is the number of horses' power on c. Ilequired the power of an engine when the cylinder is 20 inches diameter and steam 30 pounds per square inch. Set 30 on B to 4 on a; and against 20 on n is 30 horses' power on c. The same is effected on the common rule by setting the force of the steam on b to 25 J on x. Of Engine Boilers. How many superficial feet are contained in a boiler, 23 feet in length and 5.V feet in depth ? Set 1 on B to 23 on a; and against 5.5 upon b is 12G.5 square feet upon a. If 5 square feet of boiler surface be sufficient for each horse- power, how many horses' power of engine is the boiler equal to ? Set 5 upon b to 120.5 upon a; and against 1 upon b is 25.5 upon A. MANUFACTURE OF TIN PLATE. Tlio different jjrocosscs in the mannfacturo of tin jilato may bo descriljed most ])rnp(M"ly in seven distinct stages. The first begins with the bars of iron which form tlie plate ; the last terminates with an account of tlie process of tinning their surface. The d(Sfri)>tion is souxwliat technical ; but a glance at the following hcails will ciiubln the reader to comprehi'iid the whole process: 1. lio/ling is the first and most important jioint requisite to the i)rodnction of the lulten, or jjlatis of iron, i)revious to the operation of tinning them. Fortius purpose the finest quality of charcoal iron is invariably employed, which, in its commercial htate, generally consists of long flat bars. 'J'liese are cut into small squares averaging one-half an iniOi in tl-.iclaiess, which are heated n peatedly in a furnace, ami are npcatedly i)assing through iron rollers. A convenient degree of thinness having been ob- tained, the now extended plates arc "doubled up," heated, rolled, MANUFACTURE OF TIN PLATE. 23 opened-oiit, heated and rolled again, until, at length, the stan- dard thickness of the plate has been reached. 2. Shearing . — A pair of massive shears worked by machin- ery, is no\Y applied to the ragged edges of this lamellar formation of iron-plate. It is ciit into oblong squares, 1-i inches by 10, s.nd presents the appearance of a single plate of iron, beautifully smooth on its surface. A juvenile with a knife soon destroys the appearance, however, and eight j^lates are produced from the slightly coherent mass. 3. Scaling. — This process consists in freeing the iron sur- face from its oxide and scoria;. After an application of sulphuric acid, a number of plates, to the extent, we shall say, of 600 or 800, are packed in a cast-iron box, which is exposed for some hours to the heat of a furnace. On being opened the plates are found to have acqiiired a bright blue steel tint, and to be free from surface impurities. 4:. Cold Rolling. — It is impossible that the plates could pass through the last fiery ordeal without becoming disfigured. The cold rolling process corrects this. Each plate is separately passed through a pair of hard polished rollers, screwed tightly together. Not only do the plates acquire from this operation a high degree of smoothness and regularity, but they likewise ac- quire the peculiar elasticity of hammered metal. One man will cold roll 225,000 plates in a week, and each of them is, on an average, three times passed through the rollers. 5. A.nnealing. — This process is also a modern improvement on the manufacture: GOO plates are again packed into cast-iron boxes and exposed to the furnace. There is this difference in the present process from that of scaling — that the boxes must be preserved air-tight, otherwise the contained plates would inevi- tably weld together and produce a solid mass. The infinitessinial portion of confined air j^revents this. 6. Fielding. — The plates are again confined in a bath of diluted acid, till the surface becomes uniformly bright and clean. Some nice manipulation belongs to this process. - Each plate is, on its removal from the acid, subjected to a rigid scrutiny bj' women, whose vocation it is to detect any remaining impurity, and scour it fi'om the surface. The multifarious operations, it will be seen, are all preliminary to the last, and the most im- portant of all — that of tinning. Theoreticallj' simple, this pro- cess is practically difficult, and to do it full justice would carry us beyond oiir limits. We shall, however, mention the j)rincipal features. 7. Tinning, — A rectangular cast-iron bath, heated from below, and calculated to contain 200 or 30J sheets, and about a ton of piire block tin, is now put in request. A stratum of pyreia- matic fat floats upon its surface. Close to the side of this tin pot stands another receptacle, which is filled with melted grease, and contains the prepared plates. On the other side is an empty pot, with a grating ; and last of all there is yet another pot, contain- ing a small stratum of melted tin. Let us follow the progress of a single plate. A functionary known as the "washerman," 24 MANUFACTURE OF TIN PLATE. armed with tongs anil a liempen brush, withdraws the plate from the bath of tin wherein it has been soaking; and, with a dexterity only to be acquired by long practice, sweeps one side of tho plate clean, and then reversing it, repeats the operation. In an instant it is again submerged in the liquid tin, and is then as quickly transferred to the liquid grease. The peculiar use of the hot grease consists in the property it possesses of equalizing the distribution of the tin, of retaining the suiJerfliious metal, and of spreading the remainder equally on the surface of the iron. Still there is left on the plate what we may term a salvage; and this is finallj' removed bj' means of the last tin pot, which just contains the necessary quantity of fluid metal to melt it oft' — a smart blow being given at the same moment to assist the disen- gagement. The "list-mark" may be observed upon every tin plate without exception. We may add hei'e, that an expert wash- erman will finish (;,()()0 metallic plates in twelve hours, notwith- standing that each plate is twice washed on both sides, and twice dipped into the melted tin. After some intermediate ojierations — for we need not continue the consecutive description — the plates are sent to tho final operation of cleaning. For this pur- pose they are rubbed with bran, and dusted ujion tables; after which they present the beautiful silvery appearance so character- istic of the best English tin plate. Last of all thej' reach an in- dividual called the "sorter," who subjects every plate to a strict examination, rejects those which are found to be defective, and sends those which are approved to be packed, 300 at a time, in the rough wooden boxes, with the cabalistic signs with which most of us have been familiar since the days of our adventures in the back-shop of the tinsmith. Quality of Tin Plate. The tests for tin plates are ductility, strength, and color ; and to po.ssess these, the iron used must be of the best (pialit}', and all the process be conducted with care and skill. The following conditions are inserted in some sjx'cifii^ations, and will serve to indicate the strtiiigth and ductility of first-class tin platens: 1st. Thi'y must bear cutting into strips of a width e([ual to ten times th(! tliiirkmss of the i)late, both with and across tlie fibre, witliout splitting; tho strips must bear, while hot, ix-ing bent upon a mould, to a sweep cc^ual to four times the width of tho strip. 2d. While cold, the jdates must bear l)enhite is a variegntitd primrose appearancre, pro- duced upon the surface of tin ]>late by ai)i>lying to it in a heated state some dilute nitro-muriatic acid for a few seconds, then MAXtTFACTUEE OF TIN PLATE. 25 •washing it with water, dn-ing, and coating it with lacquer. The figures are more or less beautiful and diversitied, according to the degree of heat and relative dilution of the acid. Place the tin plate, slightly heated, over a tub of water, and rub its surface with a sponge dipped in a liquor composed of four parts of aqua- fortis, and two of distilled w.ter, holding one part of common salt or sal ammoniac in solution. Whenever the crystalline spangles seem to be thoroughly brought out, the plate must be immersed in water, washed either with a feather or a little cotton (taking care not to nib off t)ie film of tin that forms the feather- ing), forthwith dried with e, low heat, and coated with a lacquer varnish, otherwise it loses its lustre in the air. If the whole surface is not plunged at cnce in cold water, but if it be partial- ly cooled by sprinkling v. ater on it, the crystallization will be finely variegated with large and small figures. Similar results will be obtained by blowing cold air through a pipe on the tinned surface, while it is just passing from the fused to the solid state. Tinning. 1. Plates or vessels of brass or copper, boiled with a solution of stannate of potassa, mixed with turnings of tin, become, in the course of a few minutes, covered with a firmly attached layer of pure tin. 2. A similar effect is produced by boiling the articles ■ftith tin filings and caustic alkali, or cream of tartar. In the above way, chemical vessels made of copper or brass may be easily and perfectly tinned. New Tinning Process. The articles to be tinned are first covered with dilute siilphuric acid, and when quite clean are placed in warm water, then dip- ped in a solution of miiriatic acid, copper, and zinc, and then plunged into a tin bath to which a small quantity of zinc has been added. When the tinning is finished, the articles are taken out and plunged into boiling water. The operation is completed by placing them in a very warm sand bath. This last process softens the iron. Kustitien's Metal for Tinning. Malleable iron 1 pound, heat to whiteness; add 5 ounces regulus of antimony, and Molucca tin 2i pounds. Capacity of Cans One Inch Deep. UTILITY OF THE TABLE. Eequired the contents of a vessel, diameter G 7-lOths inches, /iepth 10 inches. By the table a vessel one inch deep, and 6 and 7-lOths inches iiameter contains .15 (hundredths) of a gallon, then .15 X 10 = 1.50 or 1 gallon and 2 quarts. 2 20 CAPACITY OF CANS IX GALLON'S. EequiretT the contents of a can, tliaineter 19 8-lOtlis inches, depth 3U inches. By the table a vessel 1 inch deep and 19 and 8-lOths inches di- ameter contains one gallon and .'d'3 thundrcdths), then 1.33 X 30 = 39.90 or nearly -10 gallons. Hequired the depth of a can whose diameter is 12 and 2-lOths inches, to contain Ki gallons. By the table a vessel 1 inch deep and 12 and 2-lOths inches di- ameter contains .50 (hundredths of a gallon), then IG -i- .50 = 32 inches, the depth recpiired, viz. : .50 ) 16 ( 32 X .50 = IG gallons. Diim. ' !_ 2 3 _4 a 6 T a. 9 etifr. .03 10 10 i .03 iO 15 10 10 io 10 3 .03 .03 .03 .04 .04 .04 .04 .05 4 .05 .05 .05 .05 .06 .06 .07 .07 .07 .(8 5 .08 .08 .08 .09 .09 .10 .10 .11 .11 .11 6 .12 .12 .12 .13 .13 .U .14 .15 .15 .16 7 .16 .17 .17 .18 .18 .19 .19 .20 .20 .21 8 .21 .22 .22 .'J 3 .23 .24 .25 .25 .26 .26 9 .27 !28 .28 .29 .30 .30 .31 .31 .32 .33 10 .34 .34 .35 .36 .36 •37 .38 .38 .39 .40 11 .41 .41 .42 .43 .44 .41 .45 .46 .47 .48 12 .48 .49 .50 .51 .52 .53 .53 .54 55 .50 13 .57 .58 .59 .60 .60 .61 .62 .63 .64 .65 U .66 .67 .68 .69 .70 .71 .72 .73 .74 .75 15 .76 .77 .78 .79 .80 .81 .82 .83 .84 .85 16 .87 88 .89 .9t) .91 .92 .93 .94 .95 .97 17 .98 .99 1.005 1.017 1.028 1.040 1.051 1.06.! 1.075 1.086 18 1.101 1.113 1 125 1.138 1.150 1.162 1.170 1.187 1.200 1.211 19 1.227 1.240 1.253 1.266 1.279 1.292 1.304 1.317 1.330 1.343 20 1.360 1.373 1.385 1.400 1.414 1.128 1.441 1.455 1.478 1.4S2 21 1.199 1.513 1.527 1.542 1.55(; 1.570 1.585 1.600 1.612 1.630 22 1.645 1.660 1.G75 1.696 1.705 1.720 1.735 1.750 1.770 1.780 23 1.798 1.814 1.830 1.845 l.f-61 1.876 1.892 1.908 1.923 1.940 24 1.9r,8 1.974 1.991 2.007 2.023 2.040 2.0.56 2.072 2.096 2.103 25 2.125 2.142 2.159 2.176 2.193 2.210 2.227 2.244 2.261 2.280 26 2.298 2.316 2.333 2.351 2.369 2.;i86 2.404 2.422 2.440 2.460 27 2.478 2.496 2.515 2.533 2.55J 2.570 2. 588 2.607 2.625 2.643 28 2.665 2.6H4 2.703 2.722 2.711 2.764 2.780 2.800 2.820 2.836 29 2.859 2.879 2.898 2.918 2.93H 2.958 2.977 2.997 3.017 3.03G 30 3.000 3.080 .3.100 3.121 3.141 3.162 3.182 3.202 3.223 3.245 31 3.267 3. 2HH 3. .309 3.3:!0 3.351 3.372 3.393 3.414 3.436 3.457 32 3.181 3.50:! 3.524 3.543 3.56s 3.59(» 3.612 3.633 3 655 3.689 33 3 702 3.725 3.747 3.773 3.79.". 3.814 3.h37 3.860 3.882 3.901 31 3.93(1 3.953 3.976 4.003 1.022 L0I6 4. 070 4.092 4.115 4.140 35 4.165 4.188 4.212 4.236 4.260 4.284 4.31)7 4 331 4.355 4. .380 30 4 406 4.430 4.455 4.48:! 4.503 4.. 528 4.5.53 4.577 4.602 4.62G 37 4.6.54 4.679 4. 704 4.730 •1.7r:5 4.780 4.805 4.834 4.8.55 4.880 38 4.909 4.935 4.961 4.987 5. 01 '2 5.03S 5.064 5.090 5.120 5.142 39 .'i.ni 5.197 5.224 5.2.50 5.277 5.30 » 5.330 5.357 .5.383 5.410 40 5.440 5.467 5.491 5.521 5.548 5.576 5.603 5.630 5.657 5.684 MEASUREMENT OF BRICKLAYERS' WORK. 27 RULES AND TABLES For Computing the Wokk of Bkickx.atees, Well-Diggers, Masons, Carpenters and Joiners, Slaters, Plasterers, P.UNTEKS, Glaziers, Paters, and PLiraiBERS. Measurement of Bricklayers' Work. Brick-work is cslimateJ at the rate of a number of bricks in thickness, estimating a brick at 4 inches thick. The dimensions of a buililing are iisually taken by measuring half round on the outside, and half round on the inside ; the sum of these two gives the compass of the wall, — to be multiplied by the height, for the contents of the materials. Chimneys are by some measured as if they were solid, deducting onlj' the vacuity from the hearth to the mantel, on account of the trouble of them. And by others they are girt or measured round for their breadth, and the height of the story is their height, taking the depth of the jambs for their thickness. And in this case, no deduction is made for the vacuity from the floor to the mantel-tree, because of the gathering of the breast and wings, to made room for the hearth in the next storj'. To measure the chimney shafts, which appear above the building, gird them about with a line.for the breadth, to multiply by tiieir height. And account their thick- ness half a brick more than it really is, in consideration of the plastering and scaffolding. All Avindows, doors, &c., are to be deducted out of the contents of the walls in which they are placed. But this deduction is made only with regard to materials ; for the whole measure is taken for workmanship, and that all out- si le measure too, namely, measuring quite round the ou,tside of t'.:e building, being in consideration of the trouble of the returns or angles. There are also some other allowances, such as double measure for feathered gable ends, &c. Example. — The end wall of a house is 2S feet long, and 37 feet high to the eaves ; 15 feet high is four bricks or 16 inches thick, other 12 feet is three bricks or 12 inches thick, and the remain- ing 10 feet is two bricks or 8 inches thick ; above which is a triangular gable 12 feet high and one brick or 4 inches in thick- ness. What number of bricks are there in the said wall? A)is. 2"),C20. 7Iiickticss* 28 X 15 = 420 X 4 = 1680 contents of 1st story. 28X12 = 336X3 = 1008 " "2d 28X10 = 280X2=560 " "3d " : 6X28 = 168X1= 168 " "gable. 3416 square feet area of whole wall. 7^ bricks to squ.are foot. 23,912 By the table. 1,708 3000 SUP. ft. = 22,500 bk's 400 " " = 3,000 " Answer, 25, 620 bricks. 10 " " = 75 " 6 " " = 45 " 3il6 " " =25,620 bk's 12 28 MEASUREMENT OF BRICK-WORK, A Table by which to ascertain the number of Bricks necessary to construct any Piece of Building from a four-inch Wall to twenty-four inches in Thick- ness. The utility of the Table below can be seen by the following Example. Required the number of bricks to build a wall of 12 inches thickness, and containing an area of 6,437 square feet. Square feet 1000 GOOD: 400: 30: 7: 22,501 bricks— See table. G 135,( 00 9,000 675 158 Note. — 7.1 bricks equal one superficial foot. 6,437= 144,833 bricks. Superficial Number of Bricl B to Thick ness of feet of Wall. 4-incli. 8-incU. 12-inch. IG-inch 20-inch. 24-inch. 1 8 15 23 30 38 45 2 15 30 45 60 75 90 3 23 45 68 90 113 135 4 30 60 90 120 150 180 5 38 75 113 150 1S8 225 6 45 90 135 180 225 270 7 53 105 15« 210 263 315 8 60 120 180 240 300 300 9 68 135 203 270 338 405 10 75 150 225 300 375 450 20 150 300 450 600 750 900 30 225 450 675 900 1125 1350 40 300 600 900 1200 1.500 1800 50 375 7o() 1125 15n() 1875 2250 60 450 900 1350 ISOO 2250 2700 70 525 1050 1575 2100 2625 3150 80 600 1200 1800 2400 3000 3600 90 075 1350 2025 2700 3375 4050 100 750 1500 2250 3000 3750 4500 200 1500 3000 4500 6000 7500 9000 300 2250 4500 6750 9000 112.50 13500 400 30U0 6000 9000 12000 15000 18000 500 3750 7500 11250 1.5O00 18750 22500 600 4500 9000 13.500 IHOOO 22500 27000 700 5250 10.500 15750 2 1 000 26250 31500 «00 6000 12000 18000 24000 30000 36000 900 (;750 13.500 20250 27000 33750 40500 1000 7500 1.5000 22500 30000 37500 45000 MEASUREMEKT OF WELLS, ETC. 29 Measurement of Wells and Cisterns. There are two methods of estimating the value of excavating. It may be done by allowing so much a day for every man's work, or so much per cubic foot, or yard, for all that is excavated. Well Digging.— SuppofiB a well is 40 feet deep, and 5 feet in diameter, required the number of cubic feet, or yards. 5 X 5 = 25 X .7854 = 19.635 X 40 = 785.4 cubic feet. Sujipose a well to be 4 feet 9 inches diameter, and 16^ feet from the bottom to the surface of the water ; how many gallons are therein contained ? 4.75- X i6.5 X 5.875 = 2187.152 gallons. Again, suppose the well's diameter the same, and its entire depth 35 feet ; required the quantity in cubic yards of material excavated in its formation. 4.75^ X 35 X .02909 = 22.972 cubic yards. A cylindrical piece of lead is required 7^- inches diameter, and 168 lbs. in weight ; what must be its length in inches ? 7.5^ X .3223 = 18, and 1G8 -M8 = 9.3 inches. Digging for Foundations, tSc. —To find the cubical quantity in a trench, or an excavated area, the length, width, and depth must be multiplied together. These are usually given in feet, and therefore, to reduce the amount into cubic yards it must be divided by 27. Suppose a trench is 40 feet long, 3 feet wide, and 3 feet deep, required the number of cubic feet, or yards. 40 X 3 = 120 X 3 = 360 feet-^27 = 131 yards. 24 cubic feet of sand, 17 ditto clay, 18 ditto earth, equal one ton. 1 cubic yard of earth or gravel, before digging, will occupy about 1| cubic yards when dug. Measurement of Masons' Work. To masonry belong all sorts of stone-work ; and the measure made use of is a foot, either superficial or solid. Walls, columns, blocks of stone or marble, &c., are measured by the cubic foot ; and pavements, slabs, chimney-pieces, &c., by the superficial or square foot. Cubic or solid measure is used for the materials, and square measure for the workmanship. In the solid measure, the true length, breadth, and thickness are taken, and multiplied continually together. In the super- ficial, there must be taken the length and breadth of every part of the projection, which is seen without the general upright face of the building. Example — In a chimney-piece, suppose the length of the mantel and slab each 4 feet 6 inches ; breadth of both together 3 feet 2 inches ; length of each jamb 4 feet 4 inches ; breadth of 30 MRASUREMENT OF both together 1 foot 9 inches. Eequired the superficial contents. Alls. 21 feet 10 inches. 4 ft. 6 in. X 3 ft. 2 in. = 14 ft. 3 in. ( oi f nn • i 4 " 4 " X 1 " 9 " = 7 '• 7 " H ^ feet 10 inches. Hubble Walls (nnhewn stone) are commonly measured by the perch, which is 16.] feet lonj,', 1 foot deep, and \\ foot thick, equivalent to 24| cubic feet. 25 cubic feet is sometimes allowed to tlie perch, in measuring stone before it is laid, and 22 after it is laid in the wall. This species of work is of two kinds, coursed and uncoursed ; in the former the stones are gauged and dressed by the hammer, and the masonry laid in horizontal courses, but not necessarily confined to the same height. The uncoursed rubble wall is formed by laying the stones in the wall as they come to hand, witliout any previous gauging or working. 27 cubic feet of mortar require for its preparation, 9 bushels of lime and 1 cubic foot of sand. Lime and sand lessen about one-third in biilk when made into mortar ; likewise cement and sand. Lime, or cement and sand, to make mortar, require as much water as is equal to one-third of their bulk. All sandstones ought to bo placed on their natural beds ; from inattention to this circumstance, the stones olten sjilit oft' at the joints, and the position of the lamina much sooner admits of the destructive action of air and water. Tlie heaviest stones are most suited for docks and harbors, breakwaters to bridges, Ac. Granite is the most durable species of stone yet known for the purposes of building. It varies in weight according to quality ; the heaviest is the most durable. Measurement of Carpenters' and Joiners' Work. To this branch belongs all the wood-work of a liouse, such a.s flooring, partitioning', roofing, &.G. Large and ])lain articles are usually measured by the square foot or yard, iVc, Init enriched mouldings, and some other articles, are often estimated by running or lineal measures, and some things are rated by the piece. Joints, Girders, and in fact nil the parts of naked floor- ing, are measurcid liy tlio cube, and their quantities are found by multiplying the length l)y the breadth, and the ))r<>duct by the depth. The same rule api)li(^s to the UK^asurcmcnt of all the timbc'rs of a roof, and also the framed timbers used in the con- struction of j)artitions. Flitoring , that is to say, the boards wliich cover tlio naked flooring, is miyisured by the square. The dimensions are taken from wall to wall, and tli' 17 71 15 by 16 60 20 by 25 29 8 by 12 150 12 by 18 67 15 by 18 53 20 bv 26 28 9 by 10 160 12 by 19 63 15 by 20 48 20 by 28 26 9 by 11 146 12 by 20 60 15 by 21 46 21 by 27 25 9 by 12 133 12 b'y 21 57 15 by 22 44 22 by 24 27 9 by 13 123 12 by 22 55 15 by 24 40 22 by 26 25 9 by 14 114 12 by 23 52 16 by 16 56 22 by 28 23 9 by 16 100 12 by 2t 50 16 by 17 53 24 by 28 21 10 by 10 144 13 bv 14 79 16 by 18 50 24 by 30 20 10 by 12 120 13 by 15 74 16 by 20 45 24 by 32 19 10 by 13 111 13 by 16 69 16 by 21 43 25 by 30 19 10 by 14 103 13 by 17 65 16 by 22 41 26 by 36 15 10 by 15 96 13 by 18 61 16 by 24 38 28 by 34 15 10 by 16 9J 13 by 19 58 17 by 17 50 30 by 40 12 10 by 17 85 13 by 20 55 17 by 18 47 31 bv 36 13 10 by 18 80 13 by 21 53 17 by 20 42 31 bV40 12 11 by 11 119 13 by 22 50 17 by 22 38 31 b'y 42 12 11 by 12 1U9 13 by 24 46 17 by 24 35 32 by 42 10 11 by 13 101 14 bv 14 7i 18 by 18 44 32 by 44 10 1 1 by 14 94 14 by 15 68 18 by 20 40 33 by 43 10 11 by 15 87 14 by 16 64 18 by 22 36 34 by 46 9 11 by 16 82 14 by 17 60 18 by 24 33 30 by 52 9 11 by 17 77 14 by 18 57 19 by 19 40 32 by 56 8 11 by 18 73 14 by 19 54 19 by 20 38 33 by 56 8 12 by 12 100 14 by 20 51 19 by 22 3t 36 by 58 7 12 bv 13 92 14 by 21 49 19 by 24 32 38 by 58 7 3G GAUGING OP CASKS. Measurement of Plumbers' Work. Plumbers' work is rated at so much a pound, or else by the hundred-weight of 112 pounds. Sheet lead, used in roofin" guttering, &c., is from 7 to 12 lbs. to the square foot; and a pipe ot an inch bore is commonly from G to 13 lbs. to the yard in length. [See Table, " Weight of Lead Pipe per Foot."] OAUGING- OF CASKS. In taking the dimensions of a Cask, it must be carefully ob- served : 1st, That the buug-holo be in the middle of the cask • 2d, That the bung-stave, ixnd the stave opposite to the bun^-hole' are both regular and even within ; 3d, That the heads'of the Cask are e.iual, and truly circular ; if so, the distance between the inside of tUe chime to the outside of the opposite stave will be the head-diameter within the cask, very near. Rule —Take, in inches, the viside diameters of a Cask at the head and the bung, ami also the length ; subtract the head-di- ameter from the bung-diameter, and note the difference. If the measure of the Cask is taken outside, with calipers, from head to head, then a deduction must be made of from 1 to 2 inches for the thickness of the heads, according to the size of the Cask. ^ 1. If (he slaves of the Cask, between Uie bung and the heail, are consitlerahli/ riirved (the shape of a pipe\ multiply the difference between the bung and head, by .7. 2. If (he .staves be of a nicdiinn viirre (the shape of a mo- lasses hogshead), multiply the difference by .05. 3. If (he staves r II rre vvvii /*7/^^le.ss than a molasses hogs- head), multiply the difference by .G. 4. If the slaves are iirarlf/ stiui'njht (almost a cylinder), multiply the difference liy .55. 5. Add the i)roiluct, in each case, to tlie head-diameter ; the sum will be a mean diameter, and tlius the Cask is reduced U^ a cylinder. 0. Multii)ly the inran diameter by itself, and then by the length, and multiply, if fnr wiue-galloiis, by .(1031. The difference of dividing by 2'.il (the usual luetliod*. and multiplying liy .()o:{4 (t!io most expeditious method >, is less than oUUths of a gaUon in It gallons. ExAMi'i.K.— Supj)nsing the head-diametor of a Cask to be 21 inclus, tho bung-diameter 32 inclies, and the length of Cask 40 inchcH, what are tho contents in wine gallons? gaugixg of casks. 37 Bung-Diameter, Head-Diameter, Difference, Multiplier, First 32 24 8 .7 5.6 21 29.6 29.6 variety. Brought Length, up, 876.16 40 35046.40 .0034 Head-Diam., 14018560 10513920 multiply by 119.157760 Scpiare, 876.16 Ans. 119 galls. 1 pint. To obtain the content.? of a similar Cask in ale gallons, multi- ply 35046.40 by .032785, and we get 97.6042 (or 97 gallons 5 pintsj. Gauging of Casks in Imperial (British) gallons, and. also in United. States gallons. Having ascertained the vnrietif of the Cask, and its interior di- mensions, the following Table will facilitate the calculation of its capacity. Table of the Capacities of Casks, whose Bung-Di- ameters and Lengths are 1 or Unity. H. Ist Var. 2d Var 3d Var. 4th Var. H. .76 1st Var. 2d Var. 3d Var. 4th Var. .50 0021244 .0020300' 0017T04 .nn]6'.23 0024337 .0021120 .0022343 .0022071 .51 .0021340 0020433 .0017847 .001B713 .77 .0024482 .0024282 .(022560 .0022310 .52 .0021437 .00205 >7 .0017993 .0016905 .78 .0024628 .0024445 .0022780 .0022551 .53 .0021036 .0020702 .0018141 .(017098 .79 0024777 .0024^10 .00230021.0022794 .54 .0021637 .0020838 001S293 0017294 .80 .0024927 .0024776 .0023227 .0023038 .55 .0021740 .0020975 .0018*47 .0017491 .81 .0025079 .0024942 .0023455 .0023285 ..56 .0021845 .0021114 .00I8n04 .0017090 .82 0025233 .0025110 .0023686 .0023533 .57 .0021951 .0021253 .0018764 .0017891 .83 .0025388 .0U25279 .0023920 .0023783 .58 .0022060 .0021394;. 0018927 .0018094 .84 .002554fi .0023449 .00241.56 .0024033 .59 .0022170 .0U21.i3'i .0019U93 0018299 .85 .0025706 .0025621 .0024396 .1024289 .60 .0022283 .0021679 0019201 .011)8506 .86 .0 125867 .0023793 .0024638 .0024545 .61 .0022397 .0021823 0019433 0018715 .87 .0026030 0025967 0024883 .1024803 .62 .0022513 .0021968 .0019007 .001892.5 .88 .0026191 0026141 .0025131 .0025003 .63 . 0022-131 .0022114 .0019784 .0019138 .89 .00263 ;3 .0026317 .0025381 .0025324 .64 .0022751 .0022202 .0019964 .0(ji;i352 .90 .002;;532 .0026494 .0025635 .00255S8 .65 .0022873 .0022410 .0020147 .0019.568 .91 .0026703 .002 W72 .0023891 .0025853 .66 .0022997 0022560 .0020332 .0019786 .92 .0026875 .0026851 .0026150 ■0026120 .67 .0023122 .0022711 .0020521 .00-: 0006 .93 .0027050 .0027032 .0026412 •0026389 .68 .0023250 .0022803 .0020712 .0020228 .94 .0027227 .0027213 .0026677 •0026660 .69 .UO 23379 .0023010 .0020906 .0020452 .95 .0027403 .00273961.0026945 0026933 .70 .0023.'510 .002'il70 .0021103 .r020678 .96 0027585 .0027579 .0027215 .0027208 .71 .002364i .0023326 .0021302 .0('20905 .97 .00277-^8 .0027764 .0027489 ■0027481 .72 002377S .0023482 .0021505 .0021135 .98 .0027952 .0027950 0027765 •0027703 .73 .002391.T .0023640 .0021710 .0021366 .99 .0028138 .0028137 0028044 .0028043 .74 .0024054 .0023799 .0021918 .0021'99 1.00 .0028320 .0028326 • 0028326 .0028326 .75 . 002419.il. 00239.=i9 .0022129 .0021834 38 GAUGING OF CASKS. Divide the bead by tbe bting-diameter, and opposite tbe quo- tient in tbe column H, and under its proper variety, is tbe tabu- lar number for unity. Multiply tbe tabular mimber by tbe square of tbe bung-diameter of tbe given Cask, and by its lengtb, tbe product equals its caimcity in Imi^erial gallons. Required tbe number of gallons in a Cask {1st variety), 24 incbes bead-diameter, 32 bung-diameter, and 4 J incbes in length. 32) 24.0 (.75 see Table for tabular No. .0024195 tabular No. for unity. 32 X 32 is 1024 square of bung-diam. 96783 48390 24195 2.4775G80 40 incbes long. 99.1027200 Imperial gallons. 1.2 1982054400 9910:::72l)0 118.9232G4L0 United States gallons. Note. — Multijilying Imperial gallons by one and two-tentbs (1.2) will convert tbcm into U. S. gallons ; and U. S. gallons, multiplied by .833, equal Imperial gallons. To Ullage, or find the Contents in Gallons of a Cask partly filled. Tc find the contents of tbe occupied part of a lying cask in , gallon.s. Utile. — Divide tbe dt'])tli of the li(]uid, or wot incdics, by tbe bung-diamet<;r, and if tlie (piotient is under .5, dedu(^t from tlio (pii)ticnt one-fourlli of wbiit it is less than .5, and multii>ly tbe re- n.aiiidir by tbe wbob' caiiacity of tlic cask; tliis ])ronrth of tbat excess to tlic quotient, and mulli|>ly tlif gallons. Example 1. — Suppose tbe bung-diameter of a cask, on its bilge, is 32 inches, and tbe whole (contents of tbe cask 118.80 U. S. standard gulloiis; rerjuired tbe ullag(! of 15 wet inches. 32 ) 15. 00 i . \ (1875 .5 . 4(iS75 - - .031 25 — 4 tr^ 0078 1 25 . A 0875 - .0078125 = .4609375 X 1 1 8. 80 = 54. 759375 U. S. gallons. PLOUGHING. 39 Example 2. — Eequired the ullage of 17 wet inches in a cask of the above capacity. 32) i7.U0 (.53125 ^.5 = .03125-^'! = . 0078125 + . 53125 = .5390G25 X 118.80 = G1.040G25 U. S. gallons. Tkoof.— 04.010625 + 51.759375 = 118.80 gallons. To find the ullage of a filled part of a standing cask in gallons. RuiiE. — Divide the depth of the liquid, or wet inches, by the length of the cask; then, if the qiiotient is less than 5, deduct from the quotient one-tenik of what it is less than .5, and multiply the remainder by the whole cai^acity of the cask; this product will be the number of gallons. But if the quotient exceeds .5, add one-tenth of that excess lo the quotient, and multiply the sum by the whole capacity of the cask; this product will be the ullage, or contents in U. S. standard gallons. Example. — Sujipose a cask, 40 inches in length, and the capa- city 118.80 gallons, as above; required the ullage of 21 wet inches. 40) 21.000 (525 — .5 = . r25-^ 10 = .0025 + .525 = .5275X118.80 = 62.667 U. S. gallons. Note. — Formerlj^ the British wine and ale gallon measures were similar to those now used in the United htates and British Colonies. The following Tables exhibit the comparative value between the United States and the present British measures: U. S. measure for British (Im.) measure. wine, spirits, &c. galls, qts. pts. gills. 42 gallons = 1 tierce =34 3 1 3 63 =1 hogshead =52 1 1 3 126 =1 pipe =104 3 1 3 252 =ltun =2t9 3 12 U. S. measure for British (Im. ) measure. ale and beer. galls 9 gallons = 1 firkin = 9 36 = 1 V)arrel = 36 54 = 1 hogshead = 54 108 = 1 butt = 109 To convert Imperial gallons into United States wine gallons, multiply the Imperial by 1.2. To convert U. S. gallons into Im- perial, multiply the U. S. wine gallons by .833. Sixty U. S. ale gallons equal 61 Imperial gallons, therefore to convert one into the other add or deduct 1-GOth. qts. pts. gills. 1 1 2 3 3 1 1 3 3 Ploughing. Table showing the distance travelled by a horse in ploughing an acre of land; also the quantity of land worked in a day, at the rat? of 16 and 18 miles per day of 9 hours. 40 PLOUGHING. B'dthof furrow Space travel- ed in plough- Extent plough'd per day. B'dthof furrow Space travel- ed in plough- Extent plough'd per day. slice. ing an acre slice. ing an acre. Inches. Miles. 18 miles IG miles Inches. 14 Miles. 18 miles 16 miles 7 14 1-2 1 1-4 1 1-8 7 2 1-2 2 1-4 8 12 1-2 11-2 1 1-4 15 6 1-2 2 3-4 2 2-5 9 11 13-5 1 1-2 IG (5 1-0 2 9-10 2 3-5 10 9 9-10 14-5 13-5 17 5 3-4 3 1-10 2 3-4 11 9 2 13-4 18 5 1-2 3 1-4 2 9-10 12 8 1-4 2 1-5 1 9-10 19 5 1-4 3 1-2 3 1-10 13 7 1-2 2 1-3 2 1-10, 20 4 9-10 3 3-5 3 1-4 Planting. Table s^-iowing the number of plants required for one acre of land, from one foot to twenty-one feet di.stance from plant to plant. Feet Kg of Feet No. of Feet 1 No. of Feet No of Feet No. of distance, hills, distance, hi Is. 1 • distance hiUs. distance hills. distance hills. 1 43,560 4 2,722 7 889 10 436 17 151 li 19,360 4,V 2,151 7^ 775 lOh 361 18 135 2 10,890 5 1,742 8 680 12 3! 12 20 108 2\ 6,969 5 A 1,440 Si 602 14 223 21 99 3 4,840 (; 1,210 9 538 15 19J 25 C9 3i 3,556 6.^ 1,031 9-1 482 16 171 30 48 Weight of a Cord of Wood. Table of the weight of a cord of difl'erent kinds of dry wood, and the comparative value jjer cord. A Cord of Hiflvorv 4469 pounds Carbon 100 Maple' 2863 " " 54 White IJireh 2:i69 " " .... 48 " Bcceh 3236 " " 65 " " A.sli 3150 " " 77 ritch I'inc 19.14 " " 43 Willi" I'inc 1H6H " " 42 " Loiiibanh Poplar, 1774 " " 40 White Uak 3H21 " " 81 Yellow Ouk 2!I19 •' " 60 Red Ouk 3254 " " G9 Note. — Nearly onr-half "f the weight of a growing oak-tree consists of sap. Ordinary dry wood contains about one-fourth of its weight in water, IXTESEST RULES, 41 Charcoal. Oak, maple, beech, and cliestnut make the best quality. Be- tween 15 and 17 per cent, of coal can be obtained when the wood is properly burned. A bushel of coal from hard wood weighs be- tween 29 and 31 lbs , and from pine between 28 and 30 lbs. Wonders of the American Continent. The greatest cataract in the world is the Falls of Niagara, where the water from the great upper lakes forms a river three-fourths of a mile in width, and then, being siiddenly contracted, plunges over rocks in two cohimns to the depth of 175 feet. The greatest cave in the world is the Mammoth Cave of Kentucky, where any- one can make a voyage on the waters of a subterranean river, aud catch lish without eyes. The greatest river in the world is the Mississippi, 4,00U miles long. The largest valley in the world is the valley of the Mississippi. It contains 5, 000, (JO J square miles, and is one of the most fertile regions of the globe. The greatest city park' in the world is in Philadelphia. It contains 2,700 acres. The greatest grain port in the world is Chicago. The largest lake in the world is Lake Superior, which is truly an in- land sea, being 430 miles long and 1,0 JO feet deep. The longest railroad at present is the Pacific Railroad, over 3,000 miles in length. The greatest mass of solid iron in the world is the Pilot Knob of Missouri. It is 250 feet high and two miles in circuit. The best specimen of Grecian architecture in the world is the Girard College for Orphans, Philadelphia. The largest aqueduct in the world is the Croton Aquediict. New York. Its lengtli is 40,} miles, and it cost S12,500,(i00. The largest deposits of an- thracite coal in the world are in Pennsylvania, the mines of which supply the market with millions of tons annually, and appear to be inexhaustible. Excellent Interest Rules. For finding the interest on any principal for any number of days. The answer in each case being in cents, sejiarate the two right-hand figures of the answer to express it in dollai-s and cents. Five per cent — Mu]tix)ly bv the number of days, and divide by 72. Six per cent. — Multiply by the number of days, separate the right-hand figure, and divide by six. Eight per cent. — Multiply by the number of days, and divide by 45. Nine per cent. — Multiply by the number of days, separate the right-hand figure, and divide by 4. Ten per cent. — Multiply by the number of days, and divide by 35. 42 BELTING. Twelve per cent. — Mu'.tiplj' by the mimber of clays, separate the right-hand figure, and divide by 3. Fifteen jjer cent. — Multiply by the number of days and divide by 24. ' Eighteen per cent. — Multiply by the number of days, separate the right-hand figure, anulley, and from nothing else, and arc governed by the same laws as in friction between tlat surfaces. The friction increases regularly with the pressure. The great dift'eren(Mi often observed in tlie friction ot Ix'lts is due simply to their elasticity of surface; that is, the moi-e elastic tlic surface, tlie greater i\n' friction. /// tiihimj jtonur from iny sounu; of motion there are two j)oints wliicli control us; all the others we can control and modify to a certain extent. Ordinary Ix^lts will sustain safely u working tension of 1.') (lounds i»er inch in width. Tlie rul(! to determine th(( width of l)clt and si/e of ))ulley recpiired to transmit a giv<'n liorse-power is ciisily found; since a li()rsc-])ower is:!;!,(l(l() iiounds, ruJHi'd one foot higli ])cr minute, we must auld be covered with leather; this will allow tho belts to be run very slack, and give 25 per cent, more wear. More power can b(! obtained from using the grain side of a belt to the i)ulley than from the tiosh side, as the belt adheres more closely to tho pulley; but it should be remembered that the belts will not last quite so long, for when the grain, which is very thin, is worn off, the substance of the belt is gone. Doable LientUrr Belts are frequently used, but it is clearly a mistake, as a single leather one will transmit more of the power than a double one. DouM.' leather belts run straighter tiiaii singl ■ ones, as tli(! Hank side <.f diu; part can be jiut against tht; ba(;k of tlu; ocher. A doul)!.; leather belt will stand a greater tension than a single one, but a singl(> belt will stand all that should be put upon any belt. In eases where a belt is incapiibh- of transmitting the re(iuire(i niiioiint of jiower. ainl eireuiiistaiK^es preelud(! tlie possil)ility of Ku])stituting a wider oni', tiie dilVKMilty may be overcome by using two belts of t'le saiiK^ width, one oil the top of tlio other. Two belts run in tliis way will transmit nearly as much power as one belt the widtli of tli«- two. Iloir tit test the iinafifff of Leather for Jteltintf. Cut ft small strip of (lie leatlier about olie-sixteelitil of all inell in lliii-luiess, and ])laee it in strong vinegar. If the leatlier has been tliorouglily taiiiied an. I is of good (juality, it will remain for mouths even, immers(;d, without alteration, simply becoming a BELTING. 45 little darker in color. But, on the contrary, if not ttoroughly tanned, the fibres -will quickly swell, and after a short period be- come transformed into a gelatinovis mass. How to make Belts run on the centre of i)ulleys,—lt is a common occurrence for belts to run on one side of the pul- leys. This arises from one or two causes. 1. One or both of the pulleys may be conical, and of course the belt will run on the higher side. The most effectual remedy for this would be to straighten the face of the pulleys. 2. The shafts may not be parallel, or exactly in line. In this case the belt would incline off to the side where the ends of the shafts come the nearest to- gether. The remedy in this case would be to slacken up on the Langer bolts, and drive the hangers out or in, as the case may be, until both ends of the shafts become parallel. This can be determined by getting the centres of the shafts at both ends by means of a long lath or a light strip of board. Tighteners. — The tighteners should be placed as close to the large or driving pulley as circumstances will permit, as the loss of power incurred by the use of the tightener is equal to that required to bend the belt and carry the tightening prilley. Con- sequently there is a greater loss of power by placing it near the small pulley, as the belt is required to be bent more than when it is placed near the large one. The reason why belts run to the highest side of a pulley is due in part to a centrifugal force, and also to the fact that the part of a belt nearest to the highest part of a rounded piilley is more rai^idly drawn because the circumference of the pitlley is greater at that point. Rubber and Leather Belts. — Rubber belts will transmit nearly as much power as leather belts with the same tension; and they have this advantage, that they may be made of any length, width, or thickness, and yet always run straight, providing the pulleys are in line. Besides, their first cost is much less than those of leather, but they will not last over half as long. They cannot be run in situations where the belt rubs, nor as cress- belts, or through forks, as shifting belts, and when they give out it is almost impossible to repair them. If a Rubber Belt runs off' and becomes entangled in the machinery, ten chances to one that it will be completelj- ruined, whereas a leather belt, under like circumstances, will sustain very little injury. When saturated with oil they soon rot, and when situated in cold damp places they are liable to freeze, which has a tendency to separate the different thicknesses and ruin the belt; besides, they often freeze to the face of ptiUeys when standing still, and when started up the gum facing is torn off, which ruins the belt. A Leather Belt, if made of good stock, not overstrained and properly treated, will last for twenty years. When partly worn out it may be cut and used over again for a narrower or shorter belt; and when entirely unfit for the transmission of power it may be tised for different purposes around a factory, but wheu rubber belts are worn out they are of no value whateTW 46 BELTING. To prevent Accidents by shafts revolving M'itliin reach of operatives' garments in mills and factories. — Cover tliu shaft with a loose sleeve of sheet tin or zinc, and insert a rim of thick gnn or leather at each end to ^jrevcnt rattling. Should it become en- tangled with the garments of any of the operatives the resistance will cause the sleeve to stand still while the shaft is rotating within it, by which means the person may be extricated and accident averted. Itulef Of finding the Lent/thof Belt wanted.— Add the diameters of the i)ulleys together, divide the sum by 2, and multiply the quotient by 3|. Add the product to twice'the dis- tiince between the centres of the shafts, and the sum will be the length required. jkufe for find htf/ the Width of Belt to transmit a given llorse- Poire r,—^l\\\ti\)\y 3G,OU0 by tlie number of horse-power. Multiply the speed of the belt in feet por minute by one-half the length in inches of belt in contact with smaller pulley. Divide the first product by the second; the quotient will be the r.'quircid width in inches. Rule for calculaflng the Niiniher of Horse-Power a Belt ivill transmit, its velocity, and the number of s<|uare inches in contact with the smaller i)ulley being given. — Divide the number of square inches in contact with the pulley by 2; mu'tiply this (piotient by the velocity of the belt in feet per min- ute, and divide by 36,00). The quotient is the number of horse- power the belt will transmit. Another Kille.—Dix'ule the number of s(juare inches of belt in. contact with the pulley by 2; multiply this (pioticnt by the velocity of the belt in feet piT minute; dividi; this amount by 32,000, and the (luotient will be the number of horse-power. Rule for tinding the change re([uired in the length of a belt when one of the pulleys on which it runs is changed for one of a different size. — Take tliree times the difference between the diameters of the pulleys and divide by 2. The result will be the length of l)elt to cut out or put in. Htnv to midsnre a Coil of Belting. XM the diameter of the hole iu inches to t!io outside diameter of the roll- mul- tiply Ijy the number of coils iu the roll; then multiply thi.s by the decimal .1301), and the product will be the number of feet in the roll. To hav(! the exawt length, the average diameter must b-i iisel, if the roll is not ])erfe.-tly round, and fractional parts 0.T an inch must not be omilt",! jn the calculation. Iloir to imt (Hi a Brit. -Never place a belt on the pullej in motion; always place it liist on the loo.se pulley, or the pnlle_^ at rest; then run it on the pull(!y in motion. If the belt is ver'v heavy, and the pulleyH run at a very high speed, it is advisable to slack on the sjieed of tli(! engine; but when this is imjiracrtica- ble or inconv(-nient, care must Ix; taken to mount the belt on the exact face. The jierson caigaged in so doing must have a firm footing, and ])reveiit his clothes from getting in contact either with the belt or pulley. Where the belt is heavy, and the; loca- tion such that it is impossible to got a Holid footing and exert MOULDING AND FOUNDING. 47 strengtli in running on tlio b'lt, it is best to stop tlie engine and mount the belt on the pulley as far as possible. Then take a small rope, double it, slip one end through the arms and around the belt and rim of the pulley, and the other end throiigh the loop formed by the double of the rope; then stand on the floor on the opposite side and draw on the rope, when the belt will be hugged to the periphery of the iDullej'. When motion is com- municated it may be slipped on without any trouble, while, by letting go the end of the rope when the belt is on the pulley, the noose will be undone and the rope thrown off. — MOXTLDINa AISTD FOUNDING-. Tlie crude iron of the blast-furnace is variously disposed of : the larger portion is applied to the manufacture of malleable iron, while the remainder is converted direct into innumerable articles formed of cast iron. Occasionally, the smelter carries on the founding business also ; in which case, castings are frequent- ly made by running the molten iron direct from the blast-furnace into moulds. At other times, the crude iron is run into pigs or bars of convenient size, allowed to cool, and then charged into other furnaces for remelting. This plan affords facilities for ex- amining the quality of each piece charged, and is followed when- ever great soundness is required in the castings, — as in the case of heavy girders, beams, and frame-work of engines ; for hydraulic rams, and similar works requiring undoubted strength. The reiiieltilig ftH'iUVCes are of two descriptions; technical- ly, they are distinguished as " air-furnaces " and "cupolas." The former are large reverbatory furnaces, built of fire-brick, having a fire-grate at one end, from whence the products of combustion pass over the charge on to the flue. The floor of the central part is made sloping to the divisional bridge. At its highest part, the charge of pigs is laid, and subjected to the intense heat reflected from the fire-place and roof, until fused; when it flows over the refractory sand bottom to the hearth. The draught is maintained by a lofty chimney, bound with iron hoops, and furnished with a regulating damper at top. The dhiiensioiis of f lie fit maces are proportioned to the magnitude of the work genei"ally pei'formed in them, namely — from 3 to 10 tons at a casting ; which is the common range of their capacity. Doors are provided on one side for charging the pig-iron and supplying the fuel ; and on the opposite side is a similar opening for tapping the molten iron into the foundry. In consequence of the intense heat to which the brick-work of the furnace is subjected, a systeoi of strong plate and l)olt binding is adopted to retain the erection in position. 48 MOULDIXa AND FOCNDING. TllC' cupola is a blast-furnaco of small sizo, in wliicli tlie in- tonse heat necessary for fusion is maintained by a fan or other blast. The interior dimensions measure from 18 inches to 3 or 4 feet in diameter, and to 10 or 12 feet in height. It is com- monly made of iron plates, bolted together, and lined inside with the best fire-brick, to a thickness of 9 or 10 inches. The blast (cold) is supplied through one or two tuyeres, which, for facility of operating on variable quantities of iron, are so made that they can be inserted at different heights of the furnace. At the bottom, on the side adjoining the foundry, an opening is left for tapping the metal and removing any cinder or other matter adliering to the sides. Ettrh of fit-ese renwUinf/ fuDUircs possesses certain ad- vantages of its own. The air-furnace is prefi'rred where tough- ness and a homogeneous structure are required ; the slight de- carbonating influence of the reverberating column of carbonic acid and other products of combustion from the fire-place, ap- pears favorable to a retention of strength. The iron so treated can be filed and chipped, and otherwise cut to shape, with great facility. It contracts less, and with greater regularity, than iron otherwise treated. Cupolas are less expensive to erect where a supply of blat* can bo obtained cheaply ; and for many ojierations are ex- tremely useful. Small (quantities of iron may be advantageously fused and by means of ladles conveyed siuiuUnnt ously to severel parts of the foundry. Castings from cupfdas, however, are weaker, and less to bo depended on, than those from air-furiiaces In consefiuence, also, of the carbonizing action of the blast on the metal in the furnace, the castings prodiu'eiodiiction of stove fronts, pans, small jiipes, and the innunnrable small articles of coin- merce. phvin and ornamented, of cast-iron. Ihij sand is aiiplied to largo pipes, engine and mill work, to girders, nnd other largo castings ri'(Miiring great sireiiglh. Tjoaia is a mnditication of tho dry sand method, and is priiii'ii)ally apjdied lo large circular castings, sin^h as cylinders and wlieels. C/iiUrd cislimis nro. thoao cast in tliick iron inoulds instead of sand : the surface of the metal in contact witli the cold iron is ren.lereil extremely hard. in consef|ur'nci' of the sudden manner in whi(di it is coohid. It ia much used for axle-boxes, rollers for cofifco and sugar-mills, MOULDING y ND FOUNDING. 49 and all purposes requiring great hardness, and capacitv for re- sisting abrasion. Open sand moulding.— MonhYmg in open sand is the simplest mode, and retiuires comi)arativeIy little skill. An ex- act model of the intended casting is made in white deal wood, and placed in an excavation in the danq) sand floor of the mould- in"-bod, the top level with the floor line. Having carefully levelled the model with a T level, the moulder proceeds to ram the sand tightly round it in small quantities at a time, with the large end of a tamping-bar. The sand, placed in contact with the model, is ^selected with care, and sifted to separate any particles of iron. On attaining the level of the model, the tamping is discontinued, and the sand at the top carefully smoothed with a small trowel ; to strengthen the edges in contact with the model, a few drops of water are sprinkled over the sand. With a large iron wire, curved so as to pass under the model without touching it, the moulder jjiercis the sand all around several times ; the model is now taken out, for which piirpose an iron spike is screwed into the top, and repeatedly struck lightly, to loosen it from the sand, when the moulder carefully draws it up. To facilitate its removal, it is made rather larger above than beneath, and the adhesion of sand partially prevented by singeing the surface of the wood. In the event of any i^orlion of "the "sand having been detaclied in the act of removing the model, the damage is repaired with a little fine sand, worked with the trowel. The interior is then dusted over with some burnt sand from previous castings, or charcoal dust sifted thi-ough a horse-hair sieve. If very deep for an open sand cast- ing, the edges of the mould are prevented from rising by a series of heavy weights, disposed wherever there is space. Shallow castings have the edg;s of the mould i^rotected by thin plates : in all cases care is taken, by weights or sprigs, that the pressure of the molten metal shall not lift up the sand wall. From the top of the mould, previous to withdrawing the mo iel, a small canal is made in the sand-bed leading to the smelting- furnace or to a small pit, into which the inetal is poured from a Ix lie. The communication with the mould is closed by a small iron gate-plate, loam-jl over to prevent the adhesion of the iron until easting time. If the casting be deep, the canal is continued to the bottom of the model by a small bore-hole, at a few inches dist.ince from the body of the intended casting. Large castings require two or more branches to the canal, to convey the iron to different parts of the mould simultaneously. T/ie filliiif/ of the mould demands great attention, and requires to be done a-i rapidly as may be practicable. If the metal is run direct from a furnace, it is l)rought simiiltaneously to the several gates, and allowed to flow into the diff'erent parts of the mould in nearly the same volume. The sprinkling of a few drops of metal around the air-holes left by the wire produces a slight explosion, throu'^h ignition of the inflammable gases arising from them. These continue to burn so long as the out- side of the metal possesses the property of decomposing water. 50 JfOULDiyG AND FOUNDINa. The molten iron is carefully skimmed from time to time, and anj' oxidized matter removed from the surface. If, at the termi- nation of the running, themoull appears to be filling unequally- the defect is remedied by the adjacent stop-gates being opened or shut, as the circumstances may rcqiiire. The molten iron is never poured direct from a vessel into the mould; but in a mould partly filled, it is somethues allowed to flow direct from the ladle. The running finished, the surface of the metal is usually sprin- kled with a little dry san 1, and the casting left in its bed until sufficiently cold for removal. Jf sotiudiiess is rcqtih'ed, no casting of any kind should be removed until cooled down throughout to witliiu a few de- grees of the atmosphere; and in the case of open-run castings, a thick covering of sand should be applied to retain the heat. If removed too soon after casting, the piece is irreparably weak- ened, if not fractured and lost. Want of room in a confined foundry is commonly adduced as a reason for turning out the work as soon as it has solidified ; but a desire to turn out more ■work than the foundry is capabh^ of producing, is perhaps nearer the mark. Fivnn whatever cause it may arise, it is too evident that many disastrous accidents have arisen from the breakage of girders and mill machinerj', resulting solely from inattention to this point, thus occasioning great mistrust in cast iron as a ma- terial of construction, and lowering its commercial value. Gl'Cf'H sditd claced ui)on tlie model ; by this process a mould of t!i(! other half is impressed upon it, the cliareoal dust i)revent- ing any adhesion betwpfai the two parts of the frame. Tin' upper fraiiu! is now carefully raised, aiul the model removed from tlio lower frame, any slight iinperfeetiou in the mould being r(>])aired by till! use of a little moistened sand and a small trowel shaped for tlu! purpose. The two j)arts of tlio frame arc; now joined to- gether by means of eornsjionding jjins and holes, and a cavity remains of the form of the requircMl easting. SitKill (li'ticlcH uluo liavo a bottom box, and, if of a complex MOULDIIvG AND FOUNDING, 51 form, may require several boxes for their complete formation. Pulleys, for instance, require a three-part box — a top, middle, and bottom. The moulding boxes, whether for green or dry sand, are made of cast iron, with cross ribs, wherever the nature of the model permits, for holding the damped sand. The sepa- rate parts are made to iit each other accurately by taper pins, through which keys are driven to bind the several parts lirmly together during the operations of moulding and casting. If the several parts of the box are large, requiring the assistance of a crane for handling, each part -is furnished with trunnions, on which it is turned over, and its under side dressed up by the moulder. The filling of the mould is conducted in much the same manner as with o^Den castings, a suitable jet being left for the escape of confined air. The tnoiildhiff of imUens, as requiring a three-part box, very well exemplifies the principles of the art. The model of the pulley is made in two halves, fitting each other with suitable drilling pins. If several are to be cast from the same model, a cast-iron one is commonly made from a wood pattern, and sub- sequently fitted to remove any asperities on the siirface. In the bottom part of the box the lower side of one-half of the model is moulded, all superfluous sand removed, the exposed portions carefully smoothed over, and fine charcoal dusted over it. The upper half of the model is fitted on, and the middle part of the box clamped down. In this portion of the box the hollow edge of the pulley is moulded. The sand is again smoothed down, and the surface dusted preparatory to re-covering the top part of the box. This is placed on the middle part, and the upper side of the pulley moulded in it. Having left an orifice for the en- trance of the metal, and another for the escajje of the air, the top part is lifted ofi", with the upper half of the model adhering to it. The middle part is next lifted off; this is a mere ring of sand, filling up the hollow j^eriphery of the pulley. After removing the halves of the model, the parts of the box are replaced, pre- paratory to casting. The charcoal dust prevents the sand in one part from adhering to that in the others. DriJ sand Cftufinffs are usually prepared in boxes similar to those used by green sand moulders. 'J his is more especially needful where a great weight of metal is to be cast in moulds made of this material Dry sand is generally used without any admixture of coal dust. Castings made in this material are less liable to imperfections and air-holes than those prepared in ordi- nary green sand moulds, its porous nature permitting of a freer escape of the gases, while there is less chance of its chilling in the mould from the baking process which it undergoes before introducing the metal. Ill (ill cdsthnj pt'occKscs, much of the success of the oper- ation depends on the skilful manipulation of the moulder; on him must depend the adjustment of the mould, and the weight of the metal with which it is charged, the due admixture of the ma- terials, with that degree of porousness necessary for the escape of the gases as they are genei-ated by the fluid metal. 52 MOULDING AND FOUNDING. When complete, the several parts of the box are taken sepa- rately to a large oven, or drying-stove, and tlioronglily dried, to expel all moisture from the sand. Afterward the interior of the mould is blackened with thick washes of ground charcoal or coke, worked up with water to a 2iroi)er consistence. It is again dried, and the several parts adjusted to each other. If the box seems to require strengthening before the performance of casting, it is sunk in the sand, level with the floor of the foundry, and on the upper jjart are laid several heavy weights, siipplemental to the side keys, in keeping the structure rigidly together under the pressure of the li(juid iron. Several peculiar configurations of cast iron, also such holes aa as may be required in tlie castings, whether large or small, are formed with cores, or loose pieces of sand, strengthened wherever necessary by internal iron bars and frames. These cores are made by tightly ramming the best sand in iron or wooden boxes of the required shape, and then placing them in the stove to dry; subsequently they are blackened, and treated as the other parts of the mould. By means of a system of hollow and solid cores, all castings, whatciver be their configuration, may be made with comparative facility; and not unfrequently pieces, the construc- tion of which would se(>m to involve difficulties, are made with only a few core-box(^s and a plain model. Lo(nn itionUlimj differs from the other methods, inasmuch as no models, or core-boxes, are used; but the moulds are made directly from drawings of the objects to be i^roduced. The mould is made of a mixture of clay, water, sand, and cow-liair, which is first reduced to a paste, and thorougldy kneaded in a pug-mill. This mass is made to assume the re<£uired form by the use of various instruments; the proportions of the various ingredients being changed to suit diflerritish Association for tho Advancement of Science allotted a small sum of money for somo limited experiments on form and a])plication. More recently a commission was issued by Government to inquire into the 'n\i- j)li(ration of iron to railway structures ; but its labors were con- fined to t<5sting the stability of a few railway bridges, and col- I(!cting the verl)al opinions of engineers as to the merits of j)jir- ti(!ular brands of jjig-iron : the results of the inquiry were of little or no valu(! to practical workers in tho metal. In the United Staten, the great difl'erenco observed in the strength and durability of cast-ironordnance, ajiparentlycom- ixiseflof equally gf)od metal, le(l fn I lie urepared with it ■was controverted by the manufacturers. And at the present day the inferiority is very frequently ascribed by writers to the facili- ties which this invention affords of working up materials of a quality inferior to those capable of being reduced by a cold blast. Recent reseai'ches, however, have demonstrated that, with similar ores, fuel, and flux, the quality of hot-blast iron is greatly inferior to that of iron smelted with a cold-blast. The experiments made for the British Association, with a view of settling this point, were the Iirst of their kind jniblicly undertaken; and the results are subjoined : Tenacity iu lbs. per sq. in. Carron No. 2 quality pig-iron hot-blast, 13,505 cold " 16,683 " No. 3 quality pig-iron hot " 17,755 " " " cold " 14,200 Coed Talon No. 2 quality pig-iron hot " 16,676 " " cold " 18,855 Bufferey No. 1 quality jiig-iron hot " 13,434 cold " 17,4iJ6 The number of pig-irons tested was sixteen ; and it will be ob- served that, with one exception, the cold-blast irons are greatly superior to the hot. The single exceptional case led the experi- menters to the conclusion that the lower qualities of iron were improved by the use of hot air to nearly the same extent as the 56 PROPERTIES OF CAST IRON. higher qualities were deteriorated. This conclusion, however, was founded on a single exijeriment; and to have been of any value, a fresh portion of iron should have been taken and exper- imented on for corroboration of such a striking anomaly. l*revioiis to tJiese experhnents, the Low Moor Company — whose works in the Bradford district, ^yell known for the superior quality of the iron i^rodviced in it, had been wrought entirely with cold-blast— adoj^ted the new mode of smelting; but the reduction in quality was such that the cold-blast was re- sumed after a very brief trial. These and the other works in this district have since continued to use a cold-blast only. Ex- periments were made on the Low Moor irons as prepared by the two processes, and the lollowing results obtained, the strength of cold-blast iron being taken as unity: Mean breaking weight of cold-blast pig-iron 1.000 hot " " 831 Snhseqjientlij experiments were made at the Dowlais Works on irons renielted in an air-furnace, also on others re- melted in the cupola, with results nearly the same as those oc- curring at Low Moor, the relative strengths being: Mean breaking weight of five bars of cold-blast iron, 1.000 " " " six bars of hot-blast iron, .835 The (liscoverij that a cold-blast of sufficient density could be successfully used in fonang furnaces using anthracite fuel, resulted in some comparative trials being made at the Ystalyfera works on irons prepared by the two processes. The result of a large number of experiments tended to establish the fact of a large deterioration occurring with the hot-blast irons, the rela- tive strengths of the two irons being: Anthracite iron, cold-blast 1.000 " hot-blast 802 TJiese e,rpei'hnents, miulo on irons reduced from similar ores and under circumstances precisely etjual, temi)eraturc of of blast excepted, must be luild ci inclusive as far as regards the irons of that country. The experiments in the United States were made principally on charcoal irons; nevertheless, the re- B)ilts are even more unfavorabh; to the h<)t-blast irons. The di- minntif)n of tenacity which fillows on the heating of the blast, is shown in the following statement of the effects produced on the American furnace iron; TenBilc BtrciiKth iu lbs. por Bq. iu. IJlilHtCold 11,110 '• heated to 150'-" r2,'2i;i 'MP 1'2,!)70 250' 11,420 This pi^f-iron was ' ; and the newly-formed oxide, remaining to a certain extent amongst the i)arti(;les of iron, reduces its tenacity below that of the original crude iron. On the other hand, the exposure of the reduced iron to a current containing free oxygen results in the rapid dejirivation of carbon, silicon, phosphorus, snlpliur, Ac; the first in a gaseous combination, the rest in the slag produced in the jiroc-ess. Th<' temperature of the molten mass in the hearth is une(pial, and subject to slight variations ; tlie result is the jn-oduction of numerous slow curnaits, which successively bring the entire charge of metal under the refining influence of the passing current of gases. Irons conlaining a large )>roportion of carbon, relatively to the other impurities, are most susceptible of imi>rovement by treat- ing in this manner. ^Vith other irons, ]>re])arcd with a heavy burden of- materials on the blast-furnace, the improvement is less striking, and is attended with a larger waste of metal through oxidation. The rnpulifi/ and imtnner cf roolivy the rastiTiff directly iniluencc's the tensile strength of the metal. It is found that Kinall castings, moulded in vertical dry-sand flasks, have a less tinsile strength tlian large castings similarly mouMed, and cast from the same cliarge of iron. The diminution of strength in tlie case of the Hinall bars amounted to nearly five ]>er ('ent. Tested transvers(!ly, however, tlie strength of the metal in the Hiiiallcasting was to that of the metal in the large as 1,14') to 1,000. This ditrereiice between the coiMi>arative tensile ami transverse strengtliH of th(! iron from Uw two castings is easily ex])lained. The rapid cooling of the small bar resulted in the bIuu attaining PROPERTIES OP CAST IROJ^. 61 great hardness, an,l llie metal to be in a state of tension. Tiiis, while it increased the transverse strength, reduced the ability of the iron to bear a direct tensile force. The large casting cooled slowly, in consequence of its great bulk ; and the heat in the in- terior mass having to j^ass through the skin, produced a partial annealing of this portion. Softened in this miinuer, it was less able to bear a transverse strain ; but the equal rate of contraction of the mass was favorable to the resistance of tensile force. TJie tensile streiiffth, as influenced by the size of the masses and rapidity of cooling, varies with the condition of the iron previous to casting. If the refining process, by lengthened fusion or numerous remeltings, be carried too far, the resulting product will be of a hard, brittle quality; and when cast into small articles, be chilled to that extent as to be incapable of working with steel cutting-tools. Cast into larger articles, how- ever, and cooled more slowly, a maximum tenacity may be de- veloped, and the texture of the iron be found of a character to bear cutting-tools on its surface. Continuing the operation too long, also produces a thickening of the molten iron, until it is of too great a consistency for the proper tilling of the mould, and the prevention of air cavities in the body of the casting. The burning av.'ay of the carbon is at- tended with a loss of fluidity; and this defect occurring, there is no remedy short of introducing further portions of the original crude iron, to restore by mixing a certain degree of fluidity. Thin castings, and others reqiiiring great sharpness in the an- gles, can be successfully made only when the iron contains a large portion of the carbon contracted in the blast-furnace. Freedom fi-om air cavities demands the emploj'ment of a similar metal. Castltlfj under a head, or considerable pressure of the fluid metal, is resorted to in very many instances, in order to obtain great solidity. The density of the metal is increased, at- tended with a corresponding augmentation of tensile strength. An experiment on the comparative density and tenacity of rough pigs cast horizontally, and a moulded bar cast vertically, gave the following results: Tenacity. Density. Rough pigs, cast horizontally 14,481 .... T.OOt Bar, cast vertically lG,42t. . . .7.085 In all close-flash rasfblf/s, the head of metal is required to be several inches above the highest point of the mould, or the perfect filling may not be insured. Rollers for mill machinery, and numerous other articles, are frequently cast with a vertical pressure of two or three feet of liquid metal above the most ele- vated part of the moul 1. The effects of atmospheric pressure on the surfi\ce of the liquid iron, while cooling, has been tried, and apparently produced a small improvement in the metal. Fur- ther experiments, however, are required to show the amount of each improvement under varying pressures of blast. 62 PROPERTIES OF CAST IRON. Bij the rapid cooling of castings through the interven- tion of water, the tensile strength of the metal may be nearly de- stroyed. The unequal rates of contraction which ensue, bring into play forces greater than the cohesive jiower of the metixl is able to witlistand. A similar result is frequently observed in the case of iron cylinders, cast in thick iron moulds, with the view of hardening the surface of the casting, especially if the metal is of a high quality. Fissures running nearly parallel with the axis of the cylinder are produced on its surface, and penetrate a short distance towar.l the centre. Their production is a result of the rapid cooling of the skin of the casting, through the absorption of caloric by the mass of cold iron composing the mould. With a slow and gradual cooling of the entire mass, the skin contracts equally with the rest ; but in chilled castings it diminishes in diameter more rapidly than the interior of the in- candescent iron, which is forced out of the mould through the head while yet effectively liqiiid; but immediately solidification commences in the interior, the skin is in a state of tension, and, at its then temperature, a direct severance in one or more places is inevitable. This fracturing of the skin occurs only with irons possessing more than ordinary hardness previous to fusion; but it is only with such that an extremely hard surface to the cylin- der can be obtained. Hence, the greater the degree of hardness imparted to the iron, the greater the liability to rupture in cooling. These considerations point to the impoi-tant bearing which the manner of cooling has on the tensile strength of cast iron. The circumstance, that a very rapid cooling is frequently attended with a direct fracture of the metal before the casting has left the foundry, shows the very great attention which should be paid to this feature of the process. Unless great care be taken, the best pig-irons may be so weakened during cooling as to possess, in the finished Civsting, a tensile strength greatly be- low that of very inferior irons in other castings cooled on correct principles. Probably in a majority of castings the quality of of the original pig-iron has less to do with the ultimate strength of the piece than the mode in which the iron is treated during and after fusion. When cast into large ina-ses and slowly cooled, some time elapses before the molecules of the metal arrange them- selves into the position offering the greatest resistance to tensile strain. The experiments made were confined to the testing, by repeated firing, of heavy ordnance, with various intervals of time between tlieir manufacture and use. Pieces cast some years be- fore testing stood several times the quantity of firing of other pieces cast but a few months previously. The tensile projierties of the metal did not exjilain the diU'erence; and the form, er cent, in some speci- mens ; sulphur is a common ingredient, but may have been de- rived in part from the fuel. Manganese, magnesia, and lime exist in small (quantities ; alumina to the extent of five or six per cent. After deducting the ash of the fuel and the protoxide of the iron, there remains a considerable quantity of earthy matters, the presence of which can only be accounted for on the supposition that they have been derived from the crude iron, and that to this extent the cast iron has been purified of alloys. l*inl(llinf/ the rcjiixil nnfal. — The further rtfinement of the iron fnnn the blast rctining-furnace is conducted in re- verberatory furnaces, technically termed " puddling-furnaces," in which, by skilful manipulation, it is deprived of most of the remaining alloy. The puddling-furnace consists of a rectangxa- lar erection of iron plates, nearly six feet high, the same distance between the two sides, and twelve feet long, lined throughout with fire-brick. At one end is a fire-place aboiit three feet square ; divided from the fire by a brick bridge is the body of the furnace, six or seven feet long, and three and a half feet wide at its widest part, resting on a cast imn bottom-jjlate, on a 'evel nearly with the bars of the fire-place ; the farthest end of the furnace is con- tracted to eighteen inches in width, where it joins a brick chimney thirty-five to forty feet high, furnished witli a damper at top. The fur 'ace is arched over with fire-brick ; and to pre- vent the sid(!S from being thrust out by the exjansinu of the heated bricks, a number of stout wrought-iron bolts ef)nn( ct the two si le- plates, which receive the thrust of the arch. At one side of the })odv a working-door is jilaced, in a stout cast-iron frame ; the bottom eight or ten inches above the iron bottom of the fiirnao'. The door is moved vertically by a balanced lever, the inner side fitted with a brick protecting lining, and is f\ir- ni8hef coal. The cinder ])rodiiee(l during tlie i)ud(lling procress flows over a small bridgf^ in tlie flue, and through an opening in the bottom of the stack to the outside To maintain MANUFACTURE OF WROUGHT IRON. 67 the stream of cinder sufficiently liquid for running, a small coal- fire is maintained at the foot of the chimney, from whence the cinder flows into a receptacle provided for the purpose. The cast iron bottom-plate is supported at short intervals by cross-bearing bars and pedestals; air is allowed free access to it from below. Indeed, without this precaution, the bottom would be imme;liately fused. Occasionally a portion of the brick-work of the side of' the furnace next the body or working part is re- moved, and cast iron blocks, cooled by a current of air or water, substituted. Ansnmim/ that a charge has been withdrawn from the liot furnace, the process is recommenced by charging through the furnace door a quantity of refined metal, broken into small pieces: from four to five cwts. constitute a charge. The pieces of metal are evenly distribiated over the bottom as far as practi- cable in an inclined position, the door shut, and a little dust thrown around its edges to exclude the cold air. Attention is now directed to the fire, which should be cleaned, fresh fuel added, and the damper f ally opened, to allow of an intense heat being generated in a few minutes. The edges of the pieces of metal soon attain a white heat, and begin gradually to soften ; the portion of the charge against the fire-place attaining a melt- ing temperature. The "puddler," as the attendant workman is called with a stout i on bar inserted through the notch in the door, lifts u^j the coldest pieces and pushes them forward into the hottest parts of the furnace, until the whole is nearly dis- solve! into a liquid mass. When a portion of the iron has been melted, the hooked bar is inserted and the entire mass raked up and exposed to the reverberating action of the hot gases from the fire. At this stage, the inside of the furnace presents a scene of' intense brightness, and an inexperienced eye is finable to dis- tinguish the metal through the dazzling whiteness of the whole of the interior. Through the small notch in the door, the pud- dler conducts the operation by constantly raking up the fluid iron, in order that the gases of the reverberatory current may play on the whole, thus lifting from the bottom any portions that may have set through lowness of temperature Since the current has no power to penetrate the liquid iron, and thiis com- bine with the carbon and other alloyed matters, as in the blast- refinery, the i^ud.ller's principal diity is to mechanically agitate the particles, so that every portion may be successively brought in contact with the free oxygen in the current. The assistant pud Her attends to the fire, which he maintains in full activity; at other times he relieves his partner, or works in conjunction with him. After some time thus occupied, the puddler will have separated the larger portion of the alloyed matters from the iron, and brought it to that point technically known as "coming to nature." When this is the case, the metal is seen to attain con- sistence, and a curdy-like matter is collected by the hooked bar; this rapidly augments, iintil a sufficiency has been collected to- gether to form a ball or bloom. A second, third, fourth, and fifth collection is successively made and placed aside in the fur- G8 MANUFACTURE OF WROUGHT IRON. nace. The churge of refined metal will thus have been converted into five portions, but some workmen divide it into seven or eight. While collecting the metal into balls, a somewhat lower temperatxire prevails ; but immediately tliey are formed, the damper is again opened, and the heat of the furnace forced, so as to rapidly agglutinate the particles of metal in the balls. Dur- ing the raking and stirring of the tinid iron, the door is wedged fast in the frame, for which purpose the latter requires to be made very strong. The securing of tlie door is especially requi- site in forming the blooms, since with the heavy hooked bar it aflbrds the puddler an excellent fulcrum for compressing and hugging the bull, to expel as much as possible of the cinder, and at the same time; give it a favorable form for yield. The forma- tion of the balls completed, the damper is lowered and the door opened; they are now withdrawn and conveyed to the squeezer or hammer, for compression into oblong blooms. The yield or produce of blooms will amoiint to nearly ninety-five per cent, of the metal charged — the consuiniition of coal-fuel averaging in weight one-half as much as that of the blooms produced. JL superior crouinuij of fuel is obtained by lengthening the body of the furnace, so as to admit of the succeeding charge being placed on the part of the bottom adjoining the stack some time before the charge under operaticm is withdrawn. In this way the new charge is heated to redness without serious detri- ment to (ho charge in covirse of being balled up, .and a considera- ble saving of time and fuel is effected. The furnace produces nearly one-fourth more blooms, with tlic same daily consumption of fuel, by this process. Economy of time and fuel is still fur- ther increased by drawing the supply of refiniul metal direct from the fining hearth in a fluid state — the fuel and time ex- pended in melting the iron being thereby saved. This mode of working, liowever, has not been extensively adopted, difficulties having been met with in effectually separating the refined iron from its accompanying cinder. The refinimj of rriidc iron in the reverberatory furnace, embraces in one furnace the separate oi)erations of refining and puddling. In dimensions and general arrangements, the fur- naces employed, known in the trade as "boiling furna(5es," are very similar to ])Uildling-furnaces. The charging and first ])art of melting are similarly conducted in both j)rocesst's; but after the fusion of the crude iron on tlio bottom of the furna(^e, tiio appearances presenti'd are very dissimilar to those witii refincul metal. At first the licjuid iron forms a level sheet, which grailu- ally swells up with the rapid mani|)ulation of the workman, until it has risen six or seven inelies abovi^ its former level. The en- tire mass ap])(!ars to heave and boil; iniiuiuerabhi erui)(ions arise on its surface and, bursting, discliarge tlieir ])ent-up gases. The jiuddler must bi; incessant in liis luaiiipulatioiis; every ))fn-t ion is to be raked up and ex]n)sed to tlie oxidizing influences of the current of the; gases, until the diininislied action siiows the near comjiletion of Mio refining i)art of the process. At this stage a careful manipulation, with a judicious regulation of the temper- MANUFACTURE OF WROUGHT IRON. 69 ature, results in tbc segregation of the iron into particles of a pasty consistence, which eventually agglutinate by pressure into masses of the required size for blooms. The conclusion of the process, the drawing-out of the blooms and recharging, difl'ers from this part of the puddling process only in the tai)ping oft" the larger portion of the cinder produced previous to recharging. The risintj of the molten mass appears to result from the expansive action of the recently-formed gases against the viscid cinder. By attention to the temperature and consistence of this cinder, the rising may be partly controlled; but the nature and quantity of the alloyed matters greatly influence the process. Since the carbon combined with the metal has to be eliminated, by first converting it into carbonic acid, a greater or less amount of carbon will resiilt in a corresponding rising, and lengthened manipulation, for its exposure to the oxygen of the reverberating column from the fire-place. Iron containing a maximum per- centage of carbon, with a deficiency of earthy matters in alloy, is refined with difficulty; and requires an addition of cinder from the mill-rollers, to protect the metal from a too rapid oxi- dation. Crude iron of this character also works hot in the fur- nace, and great difliculty is met with in bringing it to the ag- glutinative point for balling iip. This probably arises from the heat evolved by the combustion of the excessive percentage of carbon in the crude iron. "Where the quantity of carbon is large, as in Scotch irons smelted from carbonaceous ores, the heat thus evolved, with an ample supply of air, is sufficient to raise the temperature to a degree injurious to the successful manipulation of the iron, and dangerous to the metal bottom. Throughout the process, also, the temperature, from the same caiise, is less under the control of the workman. VtirloHS hiveiltiOilS have been tried as auxiliaries for the more perfect separation of the matters in alloy, but very few have stood the test of experience. The application of steam, at one time promised- to be an essential improvement. High-pressiire steam was conveyed in pipes to the bottom of the molten iron in the blast or reverberatory refining-furnace, and in ils escape up- ward agitated the iron, thereby increasing the surface exposed to the action of the air in the gaseous current from the fire-place. The white-hot iron decomposed the steam into its elements of oxygen and hydrogen; a portion of the former reacted on the carbon in the mass, producing carbonic acid, while the latter was free to combine with any sulphur present. With some irons, the increase of temperature on the combustion of the carbon was considerable, and greatly expedited the operation. Theoreti- cally, it seemci that the use of perfectly dry steam should leave little to beeflfected in the way of refining crude iron; and the fact of the invention having been repatented five or six times within the last few years, shows that much attention is directed to it. Nevertheless, the use of steam has been abandoned in the works where first tried, and the realization of the theoretical advantages is still a desideratum, Mr. Nasmyth, who last tried the experi- ment, having come to the conclusion, after many experiments, 70 MANUFACTURE OP WROUGHT IRON. that the steam-condenser had the effect of reducing the tempera- ture of the metal in the furnace. The sepdrafion of the alloyed nuttfers has also been attem{3te 1, by adding in the refining process various substances, singly or in mixture. One of these mixtures consists i)riueipally of oxide of manganese with charcoal, plumbago, and nitrate of potash In a second mixture, the ingredients were tap cinder, hematite ore, coke dust, fire-clay, and chalk; a third was com- posed of sulphur, nitrate of potash, potash, borate of soda, and suljihate of alumina; a fourth consists of jjeroxide of manganese, common salt, and potter's clay. These and other patented com- positions, however, have not answered m practice. Ground hem- atite, nearly free from silicious matter, added in small quanti- ties at a time, facilitates the puddling operation, as also do rich oxides generally; but it is essential that they be free from dele- terious substances. Th4i re/inin(f of the iron by the decomposition of water, has also been several times attempted. This is done by pouring the liquid iron into a quantity of water sufficiently large to pre- vent the iron heating it above the boiling point. The white-hot iron, falling in finely divide I streams, decomposes a portion of the water, liberating oxygen, which reacts on the carbon; the hydrogen, similarly set free, acts on the sulphur, thus forming sulpliureted hydrogen. Cold iron, immersed in water, appears to slowly undergo a similar alteration of composition; but in this case a portion of the metal is oxidized. The invention is a very old one, having been used more than half a century ago. It was recently male the subject of a patent, which a pi-ofessor of met- allurgy, in his inaugural address, adduced as a striking instance of the ignorance prevailing among manufacturers. Chemically, however, the discharging the iron into water is a valuable in- vention; while, practically, the odor of sulphureted hydrogen, evolved during the pouring of sulphury irons, is too apparent to doubt the good effect produced on the quality, when the opera- tion is properly conducted. The refining of iron in reverbcratory furnaces, is sometimes practised on tlio liipiid metal run direct from the blast-furnace. A saving of fuel results from this procedure, and the quality ap- pears to be slightly improved when skilfully conducted. It ne- cessitates the erection of the reverbcratory furnace and forge close to the blast-furnace, which is a disadvantage iu the majority of works, and leads to a temperature in tlic forge almost unen- durable. Shingliug Puddlo-Balls. The white hot lialls of the i)uddling-furnaco are removed to the hammer, to be furtln r shaped before passing through thiuoUers. The forgc-lmiumer or helve, is usually of a T form nn thital and repairs. In devising a substitute for either, it is nece.ssarj' to bear this item in mind ; for it is very evident that an apparatus which works at a higher rate cannot successfully, in a commer- cial point, compete with its cheaper rival. 2he steam-liannner has likewise been pressed into the service of the iron manufacturer. This apparatias answers admirably the varyiogworkof the engine-maker and millwright ; but for iron-making purposes it possesses no superiority over the common forge-hammer, though several times more costh'. The balls of porous iron trom the piiddler are so nearly alike in size and hardness, that little variation is required in the blows, which the common hammer gives with great rapidity. Kolling the Bloom. TJic hlo<»ti from the hammer or squeezer is passed first be- tween a i)air of roughing-rollers (in Staffordshire they are called "bolting-rollers"), and then between a pair of finishing-rollers, to convert it into a flat bar. The two pairs of rollers, and their connecting spindles, pinions, frames, and appendages, are technically called a "train." Commonly, the rollers are sixteen or eighteen inches diameter, and three or four feet long, with end bearings nine or ten inches diameter, and stpiare or fluted projecting ends, by which they are driven. Tiny are cast of tolerably hard iron, and turned in a lathe to the required longi- tudinal section. Very strong pinions couple together top and ])ottom rollers, so as to deliver the iron simultaneously in the same direction. The cast iron frames require to be exceedingly massive, and substantially fitted with adjusting screws and nuts. At one end, the train of rollers is connected to a prime-mover (generally steam), by wliieh they are driven at the rate of sixty or eighty revolutions per minute. The ineiiualities of motion, ■which otherwise would be very great, are met by a ]ions, and is reduced from five indues diametc^r and fifteen inclu's long, to a flat bar three inclii's wide, lliree-rpiarters of an inch thick, and elc'ven f(;et long. Tlio rolling and returning over tho rolls oc- cupies a minute and a qtiarter ; the Bhingling, half n minute ; Manufacture of wrought iron. t3 and from t ae cliarging of the refined metal to the delivery of the finished puddle-bar nearly one hovir and a half will have elai^sed. A considerable difference is observed in the quality of puddle-iron, from the two methods of refining. The blast-refin- ed iron possesses greater fibre, and altogether produces a better malleable iron than the product of the reverberatory furnace. Chemical analysis shows the latter to contain an excess of phos- phorus and sulphur, and also a larger quantity of silicon. Their presence in greater quantity seems to point to the incom- jjleteaess of the reverberatory process for refining. The irons made by this process are very generally hot-short (that is, brittle when hot), and incapable of being rolled into some intricate forms of finished bar-iron. When cold, however, the purest specimens possess considerable tenacity. It is a question whether the cleansing the iron of the alloyed matters can be efficiently performed in a single operation, with- out the employment of a blast. Chemically, the constituents of refined iron from the blast-refinery accord very nearly with the composition of puddle-bar from the reverberatory refinery. Hence the bars from the former are more pure, by the quantity of alloy removed in the puddling process. This defect of boiled bars deserves the serious consideration of manufacturers in more than one district, which recently has lost its character for making superior qualities of merchant iron. Tlie matters in allot/ are principally derived from the ore ; the sulphur partly froin the fuel. In the preparation, then, of the best irons, especial attention must be i:)aid to the constitu- ents of the ore used in the smelting-furnace. If these are un- favorable as to qiiality, it is hopeless to attemjjt the complete separation of the injurious ingredients in subsequent processes, other than with a ruinous waste of metal and labor. The blast- refinery removes a portion, the puddling process a second por- tion, and the reheating furnace a further quantity ; but the re- sulting malleable iron is still contaminated by the presence of minute quantities of the alloy, which it is nearly impossible to wholly eradicate. Phosphorus and sulphur are commonly con- sidered the substances which exercise the greatest deteriorating influence on quality; it is, however, highly probable that silicon, calcium, magnesium, and a few other substances, impair the quality to nearly an equal extent. The cinders produced in the puddling process appear to be of a different composition to those from the boiling furnace. The latter displaj' a larger amount of lime, phosphoric acid, sul- phur, and silica ; in fact, are not widely difterent from some varieties of the blast-refinery cinder. By adding together the constituents of the refinery and puddling cinders, it is seen that the proportion of injurious matter removed, relatively to the quantity of iron, is very much larger than in the boiling process. A. difference of quality is observed between the iron worked with a forge-hammer, and such as is worked with a squeezer. The former is found to be more tenacious and freer from cinder than the latter. This difference, it is generally believed, arises 74 MANUFACTURE OF WROUGHT IROIT. from the motion of the squeezer, which is grailual and iiressing, while the hammer violently expels the impurities by heavy blows given in quick succession. A preference is very generally given to the hammer, where the quality is considered of paramount importance. The lKiU'mss brittle than others, and possess a limited amount of elasticity; in other respects, how- ever, they show the characteristics of cast iron. Exposing thin castings from these ores to heat along with ground hematite in clo.se vessels for a long period, results in the abstraction of most of the carbon, and the conscstiuent production of limited malle- ability. Attempts have been maths, and are now being made, to convert the crude cast iron into wrought iron, by a system of blast-refining without fuel, and subsequent application of the hammer or S(iueezer — a process which we shall describe in de- tail, althougli it has not as yet attained such certainty as to justify a decided opinion of its merits. Mere refining, however, even with tlie addition of tiuxes, fails to produce malleable iron. Manipulation to a certain extent is essential to the development of the malleable principle, which then progresses jjroportionately with the working. Various oxides and snlphurets, however, possess the property of retarding and sometimes entirely de- stroying the agglutinous character of the iron at the critical point. Their presence is shown by the inability of the puddler to ball up his iron, which persists in nitainin^^ the consistency of a dry pebbly mass. Tlu' trc.Ulhui prhiriplj' of trroiUfht *j'o*/, also devel- oped at this critical point in the operation, is etjually character- istic of the singular i)roperties of the metal. Here, also, analysis fails to point out the acting cause why some irons are (lapabh; of welding and othi^rs not; nor does it explain tlie reason of iron Vjeing so pre-eminently distinguished for tliis inoperty over all other metals. Various theories have been propoundiears to be the acces- KJon of a aniitly devoid of this iirinciplo retain their hardness uj) to the moment of li(|Uera(rtion; conse- quently no opp(jrtunity is offered for union in the malleable state. MANUFACTURE OP WROUGHT IRON, 75 Cutting Puddle-Bars to Length. This is performed by powerful lever shears, containing steel knife-edges, driven by the same power as the rollers, and at nearly similar velocities. The propoi-tions of the shears intended for cutting bars cold, are considerably heavier than for bars di- rect from the finishing rollers. Knives, four inches deep, one and a half inch wide, and sixteen inches long, bolted to the fixed and movable arm of the apparatus, are a common proportion. Great care is required that the knives pass each other with a certain degree of tightness, or the wedge-like action of the flat bar at the point may break ofl" the movable arm. This is more espe- cially the case with shears for cutting cold iron, which, in ad- dition to being kept in contact, require the knives at all times to be clean with a sharp V-cutting angle. The knives of shears cutting hot bars are kept from softening by a small current of water directed against them; but the same degree of sharpness is not required here as in cold shearing. Piling the Cut Puddle-Bars. To convert the puddle-bars into the various forms of the fin- ished malleable iron met with in commerce, the short pieces from the cutting-shears are piled one on the other to form a mass of a weight suited to the weight of the bar to be operated on. Ihe piles vary greatly in size and arrangement, according to the magnitude and purpose of the finished bar. If common bar-iron of average size be the order of the day, they will measure some two feet long and four inches square; with larger sizes they meas- ure five or SIX feet long by ten or twelve inches square. A nearly uniform size in the pieces composing the pile, whatever be its dimensions, is essential to successful results. The piles are con- structed to the number of six or seven, or nioi'e, on an iron frame standing about two feet above the floor, from whence they are taken as required by the workmen engaged in bringing them to a welding-heat preparatory to rolling. Heating Furnace. A rcverberatory furnace of nearly the same dimensions as the puddling-furnace, but having a refractory silicious sand-bottom, is employed in heating the piles. The bottom is rendered even, and declines from the charging door to the back and flue, for the flow of the liquid cinder. Cast iron framing, with tension bolts to restrain the pressure of the arched roof, and the same power- ful chimnej^ are required as in the puddling-furnace. The piles are inserted into the furnace on a "peeler," and disposed on the bottom in such manner that the workman can readily turn them over, or grasp them for withdrawal. The number charged at one time is inversely as the size; but for small piles of the dimensions given above, they may be taken at eight or ten. When properly 76 MANUFACTURE OF WROUGHT IRON. disposed on the bottom, the charging-door is shut and all en. trance of air around it prevented by a thick dusting of small- coal or ashes. The grate is now cleaned of adhering matters, coals added to the fire, the stoke-hole closed with the fuel so as to prevent the admission of air, and the damper opened to its widest. An intense heat is generated, and communicated by de- flecting from the roof to the charge in the body of the furnace. The piles receive the heat unequally, those nearest the fire-place being heated first; it is the duty of "the attendant to inspect from time to time the condition of the charge, and by exposing them alternately to the strongest action of the fire, to heat them to the same temperature, occasionally turning them over to expose the under side equally with the others. When the piles are large, turning over to heat the under side is the only operation to which they are subjected in the furnace. At a white heat the softening of the iron is followed by the flowing of a quantity of cinder from the interstices, which nins down the flue to the exterior of the chimney. Considerable dexterity is required in managing the fire; for though in theory the mere heating of a few masses of iron may seem a very simple operation, in practice it is difi&cult of attainment economically. The flow of cinder over the mass, when at a white heat, protects them to a con- siderable extent from oxidation; but great care must betaken that no air gains access to the iron during the process. If this precaution be neglected, and air enters the furnace, either through the fire being too open or tlie door imperfectly sealed, the metal is rapidly o.vidized, and great loss results. The particles of oxide of iron formed, eventiially cool into brittle scales, which cut into the malleable iron, and destroy its continuity in the subsequent processes. If allowed to proceed, the oxidized surfaces of metal cannot be brought to a welding condition; and whatever pressure be applied, the pieces of pudille-bar composing the pile cannot be forced into union. It may be here nMuarked, that by bringing gaseous and solid carbon in contact with the oxide in the blast -Yurnace, the oxygen forms new combinations, liberating the iron in the metallic state. The superior affinity at high temperatures of carbon over iron for oxygen, has been taken advantage of from time immeniorial for the ready separation of oxygen in oxides of iron. But in its progress from the blast-furniice to the state of a finished bar of malleable iron, in the absence of carbon, the iron has a constant tendency to return to the condition of an oxide. In the blast- refinerv, onedialf of the metal \\ould be oxidized, were it not for th(! strutiim of carbon fuel covering the molten iron, and which decoiii|)oses the oxide nearly as fast as it is foruK'il. In the pud- dling-'iirnace the metal is unprotected by carbon, and the great- est care and skill is demnnded from tlie puddler tli.it a large por- tion is not lost through wasteful oxidation. The heating process is similarly situated; access of air to the iron causing a portion to revert to its original state in the ore. So much of the iron as is thus oxidized in the several processes pass roller is made a fraction larger than the bottom, in onler to throw the liar down on the guides as it is delivered >)y the rollers. Tlie guides are two tiers of heavy wedges, the points f)f the top tier resting on tlie toj) of the bottom roller, while th(! lower tier is k<'|)t in reserve iimiKMliutely below. In its delivery the liar is coiidueted in a straight line by these wedg<'s, instead of turning down underneatli the roller, as it otherwise! woidd. If, fnun accident, the guides opjwsite any (me groove are displaced, the end of the bar is likely to return under the roll, and lio united witli the other ]>art into a solid ring. This untoward accident may also occur through defect in MANUFACTURE OF WROUGHT IRON. 81 the iron, the more so if partially oxidized by long exposure in the heating furnace. In this case a portion of the pile separates from the rest, and following the course of the top roll, is welded into a massive iron ring Considerable delay occurs under such circumstances, for operations must be suspended while the iron ring is being cut through ; and this requires some time when the metal is hveor six inches wide and half as much in thickness. With some sections great exactness is required, and a de- viation of the thickness of a hair either way renders the bar iinsalable. If obliged to work to a very exact section, the rollers are adjusted with the greatest care, the tightening and set- screws without play, and frequent examinations made of the bars produced. With the greatest care, however, a few daj^s at most results in so much abrasion in the rollers, that they have to be sent to the turner for repairs. 'Where they rub on each other, the surfaces are frequently lubricated with black-lead and grease, or carbonaceous matter and palm oil. The ovevheatinf/ of the roUevs, by contact with the hot iron, is pi-evented by small streams of water directed on the parts of the finishing-rollers liable to heating. "With bars of a concave section on the upper surface in rolling, the water which falls on the red-hot charcoal affords an instructive example of the spheroidal condition of water in contact with substances at high temperatures. "While the bar remains at a bright red-heat, no steam is formed, the drops of water merely rolling over the surface ; but the surface of the rollers, though scarcely heated above the boiling point of water, is enveloped in clouds of steam. These phenomena of water were known to operatives in rail- rolling mills many years before the publication of M. Boutigny's experiments. Daring the successive rollings, the great pressure ex- erted on the bar expels with violence a portion of the remaining cinder, and leaves the iron comparatively i^ure. This cinder is composed, to the extent of about ninety per cent., of magnetic oxide of iron; the remaining ten percent, of silica, phosphoric acid, lime, sulphur, and other bases, depending on the local constitution of the crude iron. Cutting Bar-Iron to Length. The finished hnv is taken from the rollers and cut to the required length whilst hot. This is done either by lever shears, as in the case of puddle-bars, or circular saws revolving at great rapidity. The latter, a modern invention, performs the work in an exceedingly neat and expeditioiis manner, and is applicable to iron bars of all sizes irrespective of section— an ad- vantage not possessed by any shears. Thin merchant-bars are frequently cut cold, in order to show off the texture of the iron; but large bars of every description are cut whilst hot. The sawing apparatus consists of a pair of steel disks, four feet diam- eter and one-eighth of an inch thick, with coarse teeth on the 4* 82 MANUFACTURE OP WllOUGHT IRON. edges, mounted on a spindle about four feet long. By a small pulley-wheel on the centre of this spindle, motion is communi- cated by bands from larger wheels driven by the engine. Against the outside of each saw, but near its front edge, is placed a nar- row sliding-frame of cast iron, equal in length to the longest bar rolled, on wliich the red-hot bar is placed and retained in its position by stops. The ragged end of the bar is made to project sufficiently in front of, and finally pressed against, the saw, by which it is cut from the body in a few seconds. If gradually performed in fifteen or sixteen seconds, with good saws, the emls of the bar have a smooth, polished apjiearance ; performed in three or four seconds, the ends are less smooth. The second end of the bar is cut in a similar manner by the other saw; the projecting ends ciit off" being placed aside for remanufacture. Great care is commonly reqiiired in cutting the second end, as the amount then cut off regulates the length of the bar. To in- sure the recjuisite accuracy in this respect, the second movable ])latform is furnislied with a sliding-gauge, the distance of which from the face of the saw regulates the length of the finished bar. Allowance, however, has to bo made for contraction of the bar from its red-hot state; and some attention requires to be given to the (litference of temperature at which some are cut, in order to obtain bars of ncarl / uniform length. Ttw sinrs vci'itlre 1,000 to 1,5()0 revolutions per minute, equal to a velocity at the cutting-edge of 1-12 to 213 miles per hour. Their edges are kept from overheating by dipping into narrow cast-iron cisterns containing water. When cutting, the shower of sparks created is \.artialiy confined to the vicinity of the saws by sheet-iron casings, supported over the upper edges of the saw. The entire apparatus requires to be fitted up very correctly, the revolving parts evenly balanced, and working in good brasses rigidly fixed to jiedcstals and a heavy substructure. Every twenty- [our hours the saws require sharpening, and are then replaoetion of machinery for this purpose. The iti U-st ra iyhteni iKj press consists of a massive cast- iron Iraine, witli a projecting stand on each side to receive the railway bar; on the top revolves a large shaft, carrying an eccen- tric caiji, which acts on a slider moving vertically in grooves in the large frame immediately over the projecting stand. The bottom of the slider is slightly bevelled, and at the down stroke reaches to within four or live inches of the rail. When straight- ening, the bar rests on two shallow supports, about eighteen inches apart, on the stand, the convex side uj); a wedge-shaped key is carefully inserted under the slider, so that at the lowest movement the slider presses on the rail through the intervention of the key, and removes, at one pressure, part or whole of the convexity. The operation is repeated until all irregularities are taken out. If the benils in the bar are very short, a less distance between the supports is dfmanded. Considerable delicacy is required in using the tajierkey; if projected too far, the niil may be bent in the reverse direction, or completely broken if made of cold-short iron. Commonly the slider moves up and down about thirty times in a minute, t'lereby enabling skilful workmen to straighten 100 bars daily in a single i)ress. The .stmin thrown on the approaches is very great, and renders it necessary to make the whole of massive projjortions. Frequently the bar. after leaving the straightener, possesses a degree of "winding" or twist, which is detected by placing the en. Is on two planed blocks accurately levelled on tlie upjier sur- f-M-c. It is removed by grasping the ends with hmg levers, and applying a light torsional strain until the desired effect is pro- duced. Boiler-Plato Iron. This is made from selected No. 2 bar-iron, when a superior quality is sought ; but tlie larger jiortion of the jjivseiit manu- facture is rolled direct from puddle), looms. The j)ile for best l)late is built short and wide, witli an e(jii;il (piantity of pieces running along and acro.-,s it. They are brougiit toa welding beat in a reverberatory furnace of the ordinary description, and taken to the plate-iron rollers. These consist of two pairs, a slabbing and a finishing, both of a plain cylindrical form, chill<;d to extreme hardness on tiie surface. The frames in which the rollers revolve are furnished witii large tightening screws (six or eight inches in diameter . by means of wliich the top rollers are screwed addle-hall of the boiling furnace is hammered into a flat bloom, two of which are placed together to constitute the plate ; when cold, they are charged into a furnace, heated to melting, slabbed, and rolled in the foregoing manner to the de- sired thinness. Plates made in this manner, however, oxight never to be used in any description of boiler building. A very general recourse to this mode of manufacturing has unquestion- ably lowered the character of boiler-jilate iron, and led to many fatal explosions. Good boiler-jilates should not break with a less strain than twenty-five tons to the square inch of metal ; but much of what is manufactured for the purpose will not bear more than two-thirds of this strain. Nail Rod Iron. Nail rods are manufactured in two w.ij's : by rolling a bar down to the desired section ; and by cutting a thin strip of iron into a number of parallel rods, by means of revolving shears. The first metho 1 is pursued with iron for horse-shoe nails, and the superior kind of rods, forming about two per cent, of the manufacture ; and the shearing with the remaining ninety-eight per cent. The manufacture by shearing strips, is known in the trade as slitting nail rods. A slitting-mill consists of two or three heat- ing furnaces, a pair of grooved rollers for roughing the pile, a pair of smooth chillod-iron rollers for flattening it, and a pair of revolving shears, with the requisite lever-cropping shears. Roll- ers and shears are commonly placed in parallel lines, seventeen or eighteen feet apart and driven at nearly the same number of revolutions per minute by strong spur-gearing. The shears are formed of two parts, each consisting of a number of disks of wrought iron, sixteen or seventeen inches diameter, edged with steel, kept the requisite distance apart by other disks of iron of lesser diameter ; the whole firmly bolted together, and mounted 88 MANUFACTURE OF "WKOUGIIT IRON. on a cast or ■wrought iron spindle. When revolving, the Tipper series of steeled disks project into the spaces of the lower series, thus forming a number of continuous shearing edges. The depth when they project is regulated by screw bolts attached to the cast-frames; while the entrance of the iron to be shorn is regulated by guides and plates, similarly adjusted by screw-bolts. Through the bottom of a cistern at top, a shower of water falls on the steel, to keep it from softening with the heat of the bars. In front of the ai^paratus a wrought iron grated frame is con- structed of iron bars, to receive the rods delivered by the shears. The lit ode of roUiiuj may be described thus : Two or three pieces of puddle-bar, or other flat iron, are placed to form a low pile, which is brought to a welding-heat in a reverberatory furnace, and ti-ansferred to the grooved rollers. In these it is distended to a bar ten or twelve feet long, by three and a half or four inches wide, and of a thickness proportionate to the size of the intended rod. It is now passed between the smooth rollers, so as to reduce it to the precise thickness, and at the same time remove anj' roughness on the face of the iron. It is now of a width somewhat less than the breadth of the upper series of steeled disks ; and on insei-ting one end of the strip between the guides, it is drawn on by the revolving shears, and cut into as many rods as there are steeled disks in its width. The divid- ed rods are secured on light hooks, and transferred to the grat- ing. The strips vary slightly in width ; and when such is the case, or the iron is of a weak red-short character, a number of imperfect rods are shorn off at the sides, and passing aside the guides, require constant cleaning from the apjiaratus. The finished rods are cut to length, weighed into bundles, and tied up by twisting around them three or four small bands of hot iron. If placed in stock, or in carriages for conveyance to purchasei-s, great care should be taken that they do not get wet and rusted on the surface. Kods prepared by shearing may readily be distinguished from rolled rods by the'conca^■ity of the one and convexity of the opposite side; the other two sides also show the cutting action of the shears, and two edges project slightly with minute serrations. The rapidity with which nail-rods are produced by this process is perfectly marvellous to the uninitiated. Working on the smaller sizi's of rods, a mill rolling three lengths at once, as is now generally done in the largc^r mills, delivers ninety to a hun- dred rods at each operation, equal to the continuous delivery of a single rod through the week at a velocity of ten miles per hour. Hoop-Iron is manufactured from small piles or billets, rollcil tirst between small rollers having grooves on their circum- ference, and lastly between a short pair of hard cylindrical rollfirs, in which it is pressed to thf width and tliickncss dfsirrd. The great length of the bars juid their tcndenc^y to cool (piicklj', renders it necessary to propel the grooved rollers at very high velocities; but the smooth pair is driven at the more usual spei'd of niiiity or a hundriMl revolutions per miuulo This puir MANUFACTURE OF WROUGHT IRON. 89 requires to be exceeclinglj' strong, in order that the iron may be finished comparatively cold and thereby carry a blue face. Sniftll jiatft, squares, bolts, and fine irons generally are rolled with trains having three rollers in height. The addition of a third roller to each set expedites the rolling one-half; inas- much as the operation is continued in both directions, instead of returning the bar over the top roller, as in large mills. The rollers are commonly eight or nine inches in diameter ; the roughing set thirty inches long; the second twenty-four, and the finishing nine inches long : three rollers in height, instead of the two in other mills. A speed of 230 revolutions i^er minute is common and preferable to slower working; at this velocity the perii^hery of the roller moves over six miles per hoiir; and calcu- lating the several movements of the operatives in following the bar through the day, it is seen that several of them walk more than twenty miles daily at this quick rate. The rolling of snuiU flats and squares in such trains is conducted on principles similar to those pursued in larger mills; but the round iron is rolled with the assistance of double guides. Small piles, or solid pieces o^ iron termed " billets," are roughed between the first pair of rollers; in th3 second, the iron is first converted to a square and then into a bar of an oval section, pre- cisely equal in area to that of the intended round bar. The grooves in the short finishing-rollers (of which there are only two in rolling rounds) are of an exact semicircular shape, and to- gether form a complete circle. The oval bar is presented to these rollers, guided in a vertical direction by closely-fitting iron blocks, where it is violently compressed to a perfectly cylindri- cal form. To insure this being done, there must be a rigid cor- respondence between the oval and circle. If the oval is too small, the deficiency of metal to fill the circle is seen in the flat- tened sides of the latter; if too large, the excess of metal is fre- quently forced out at the sides, forming thin flanges. If the guides fail to hold the bar sufficiently tight to prevent its turn- ing around, the bar is similarly spoiled. As may be imagined, it is only very good iron that will stand the violent alteration of structure wliea comparatively cold. 90 WEIGHT OP SQUARE ROLLED IRON. Weight of Square Rolled Iron. D-om l-lG(h Inch to ^ Inches. ONE FOOT IN LENGTH. Weight. Side. Weight. Lbs. 11.883 13.52 15.263 17.112 I'J.OGG 21.12 23.292 25.56 27.939 30.416 33.01 35.704 38.503 41.408 44.418 47.534 lUB. 7 Lbs. 50. 756 54.084 57.517 61.055 64.7 68.448 72.305 76.264 80 333 84.48 88.784 93.168 97.657 102.24 106.95:1 111.75G Side. Weight. Ins. Lbs. 116.671 121.664 132.04 142 816 154.012 165.632 177.672 190.136 203.024 216.336 230.068 244.22 258.8 273.792 289.22 305.056 Illustration. — What is the weight of a bar IJ ins. bj' 12 inches in leni:,'th? In column 1st, find li ; opposite to it is 7.604 lbs., which is 7 lbs., and .004 of a lb. If the lesser denomination of ounces is required, the result is obtained as follows : ]\[nltiply the remainder by 16, point off the decimals, and the figures remaining on the left of the point give the number of ounces. Thus, .004 of a lb. = .004 X 16 = 9.664 = 7 lbs. 9.664 ounces. to ascertain the weight fob less than a foot in length. Operation. Wliat is tiie weight of a bar 6 J inches square and 9| inches long? In column 4th, opposite to C)\, is 132.04, which is the weight for a foot in length. 6.25 X 12 inches = 132.04 6. " is .5 = 66.02 3. " is .5 of 6= 33.01 .25 " is j^jOf3::::= 2.7508 9.25 = 101. 7808 pou7i(Z«. WEIGHT OF CAST IRON PIPES. 91 Weight of Round Rolled Iron. From l-16ili Inch (o 12 Inches in Diameter. ONE FOOT IN LENGTH. Diam. Weight. Diam. Weight. Diam. Ins. Weight. Diam. Weight lus. Lbs. Ins. Lbs. Lbs. Ins. Lbs. ^"n .01 \ 1344 1 56.788 1 149.328 h .041 14.975 I 59.9 J 159.456 ^^ .093 ^ 16.588 1 63 094 8 169.856 .165 '^ 18.293 5 66 35 \ 180.696 .373 3. 20.076 i 69.731 191.808 .663 8 21944 k 73.172 a 203.26 n 1.043 3 23.888 3 "8 76.7 9 215.04 -^ 1.493 J 25.92S 80.304 } 227.152 i 2.032 i 28.01 84.001 * 239.6 1 2.654 30.24 a 87.776 f 252.376 j« 3.359 1 32.512 7 91.634 10 265.4 ] 4.147 1 34.881) 6 95.552 \ 278.924 ^ 5 019 I 37.332 1 103.704 292.688 4 5.972 s 38.864 ■g 107.86 4 306.8 5 s 7 01 4 42.464 112.16 11 321.216 ^ 8.128 i 45.174 116 484 \ 336.004 i 9.333 47 952 i 120.96 h 351.104 2 10.616 ^ 50.815 7 130.048 1 366.536 I 11.988 i 53.76 1 4 139.544 12' 382.208 Weight of Cast Iron Pipes of different Thicknesses. Froin 1 Inch (0 24 Inches in Diameter. ONE FOOT IN LENGTH. Weight. Piam. Thkn. Ins. Weight. ! Diam. Ins. Thkn. Ins. Ins. Lbs. 1 1 3 06 2f ^ 1 5 05 3 H i 3.67 1 6. 1 n 6.89 a n t 8 9.8 7.8 31 I ^ 11.04 a 2 "8 8.74 3h J 12.23 \ ^ 2J 1 9.65 a ^ 13.48 3f n. 1 10.57 ^ 14.66 2. 1 19.05 1 4 }> 2a a 11.54 1 Ft h 15.91 1 £■ Lbs. 20.59 12.28 17.15 22. 15 27.56 18.4 23.72 29.64 19.66 25.27 31 2 20.9 26.83 33.07 22.05 28 28 34.94 Diam. Thkn. Weight. Ins. Ins. Lbs. H 1 23.35 29.85 1 36.73 ^ i 24.49 1 31.4 a 38.58 ^ 1 25.7 32.91 f 40.43 1 5 * 26.94 1 34.34 a 42.28 5] h 29.4 4 37.44 f 45.94 6 1 31.82 1 40.56 92 WEIGHT OF CAST IRON PIPES. Weight of Cast Iron Pipes. — CoH/mued Diam. Ins, 6 6J n H n 10 lOJ Thkn. lUB. Weight. Lbs. 49.6 58.96 34.32 43.68 5:13 G3.18 36.66 46.8 56.96 67.6 78.39 39.22 49.92 60.48 71.76 83.28 41.64 52.68 64.27 76.12 88.2 44.11 56.16 68. 80.5 9:5.28 46.5 58.92 71.7 81.7 97.98 48.98 62.02 75.32 88.98 102.9 51.46 65.08 78.99 93.24 108.84 53.88 6K.14 82.68 97.44 112.68 56.34 71.19 Diam. Thkn Ins. 11 11^ 12 12i 13 13J 14 14i 15 15i Ins. Weight. 11 NoTK. — ThcBo wcighUdu not includoauy allowaar -lor spigot and faucet euus. Lbs. 86.4 101.83 117.6 58.82 74.28 90.06 106.14 122.62 61.26 77.36 93.7 110.48 127.42 63.7 80.4 97.4 114.72 132.35 66.14 83.46 101 08 118.97 137.28 68.64 86.55 104.76 123.3 142.16 71.07 89.61 108.46 127.6 147.03 73.72 92.66 112.1 131.86 151.92 75.96 '.15.72 115.78 136.15 156.82 78.4 98.78 119.48 140.4 161.82 Diam. Ins. 16 16^ 17 17^ 18 19 20 21 22 U 24 Thkn. Ins. Weight. Lbs. 80.87 101.82 123.14 144.76 166.6 83.3 104.82 126.79 149.02 171 6 85.73 107.96 130.48 153.3 176.58 88.23 111.06 134.16 157.59 181 33 114.1 137.84 161.9 186.24 120.24 145.2 170.47 195.92 126.33 152.53 179.02 205.8 132.5 159.84 187.6 215.52 138.6 167.24 196.40 225.38 144. "^7 174.62 204.78 235.28 150.85 181.92 213.28 245.00 CAST IRON AND COPPER. 93 CAST IRON. To Compute tho Weight of a Cast Iron Bar or Rod. Find the weight of a wrought iron bar or rod of the same di- mensions in the preceding tables or by computation, and from the weight deduct the 2-27th part ; or, As 1000 : .9257 : : the weight of a wrought bar or rod : to the weight required. Thus, what is the weight of a piece of cast iron 4 X 3| X 12 inches. In table, page 108, the weight of wrought iron of these dimen- sions is 50.692 lbs. Then 1000 : .9257 : : 50.692 : 46 93 lbs. To Compute tha Weight of a piece of Cast or Wrought Iron of any Dimension or Form. By the rules given in Mensuration of Solids, ascertain the number of cubic inches in the piece, then multiply by the weight of a cubic inch, and the product will give the weight in pounds. Example.— What is the weight of a cube of wrought iron 10 inches square by 15 inches in length ? 10 X 10 X 15 = 1500 cubic inches. .2816 weight of a cubic inch.* 422.4 pounds. 2. What is the weight of a cast iron ball 15 inches in diameter ? Ball, 15 ins. =176.7149 cubic inches. .2607 weight of a cubic inch. * 460.6957 pounds. COPPER. To Compute the Weight of Copper. Rule — Ascertain the number of cubic inches in the piece ; multiply them by .32418,* and the product will give you the weight in pounds. Example. — What is the weight of a copper plate ^ an inch thick by 16 inches square ? 16-' = 256 .5 for I an inch l28X .32418 = 41.495 pounds. Brazier's Sheets are 30 X 60 inches, and from 12 to 100 lbs. per square foot. Sheathing Copper is 14 X 48 inches, and from 14 to 34 oz. per square foot. * The weights of a cubic inch as here give'., are for the ordinary metalH ; when, however, the spncific gravity of the metal under couHiileration in accu- rately known, the weight of a cubic inch of it should be substituted for the units here given. 94 SHIP AND RAILROAD SPIKES. LEAD. To Compute the Weight of Lead. Rule. — Ascertain the number of cubic inches in the piece ; multiply the sum by .41015, and the product will give the weight in jwunds. Example. — What is the weight of a leaden pipe 12 feet long, 3.75 inches in diameter, and 1 inch thick? By Rule in I^Iensuration of Surfaces, to ascertain the Area of Cylindrical Rings. Area of (3.75 + 1 + 1) = 25.9G7 •' " 3.75 = 11.044 Difference, 14.923, or area of ring. 144 =12 feet. 2148.912 X .41015 = 8S1.37G pounds. BRASS. To Compute the Weight of Ordinary Brass Castings. Rule. — Ascertiiin the number of cubic inches in the piece ; multiply them by .3112, and the product will give the weight in pounds. SHIP AND RAILROAD SPIKES. Number of Iron Spikes per 100 lbs. -P . C. Page. o .•4 «- S a. '3 Batch Nails 1-4 iu. sq're Ship Spikes or Hatch Nails 5-16 in. sq. Ship Spikes or Beck Nails 3-8 in. Bq're. Ship Spikes 7-16 inch square. Ship Spikes 1-2 inch square. Ship Spikes 9-16 inch square. Ship Spikes 5-8 inch square. Size No. Size No. Size No. Size No. Size No. Size No. Size No. in 100 in 100 in 100 in 100 In 100 in 100 iu 100 inc. lbs. inc. lbs. lUC. lbs. inc. lbs. inc. lbs. inc. lbs. Inc. lbs. 3 1900 3 1000 4 540 !5 340 G 220 8 140 1" 80 3i 1580! :n 'JO 4.1 500 5^. 310 04 200 9 120 15 00 4 l.{2) 4 800 5 4(;o ' 6 300 7 190 10 110 — - i\ 1220' 4.1 6o;i r>\ 420 Ci 280 V, 180 11 100 — . b 1020 5 580 (1 ■100 7 2(iO 8 170 . — — 6 520 (Mf 320 7A 210 ^ ICO — — — — — — — I 8 220 9 150 — — — — — — — — 10 140 — — — Riiilnnid Spikes 9-lGths square 5i inches IGO ])or 100 jnuinds. Riiilroud Spikes 1-2 inch '* GJ •' 2(.i0 jier lOJ pounds. COPPERS. 95 Burden's Patent Spikes and Horseshoes. Manufactured at the Tkot Ibon and Natl Factoby, Tkoy, New Yoek. Boat t-pikes. Ship Spikes. Hook He id. No. in 100 lbs. Horseshoes. Size in No. in inches, luo lbs. Size in inches. No. in llO lbs. 800 650 437 430 421 377 275 250 174 163 155 ■ 115 Size in inches. Size in inches. No. iu, 100 lbs. 3 10 1,750 1,468 1,257 920 720 630 497 478 362 337 295 290 210 198 4 6.V 7' I' 8J 9' 10 4 Xi 4i X 7-16 5 Xi S'ixi 5^ X 9-16 6 X9-16 6 Xf 7 X9-10 8 Xg 555 414 252 241 187 172 i 138 140 ' 110 [ 1 2 3 4 5 84 75 65 56 39 Coppers. Dimensions and Weujhifrom 1 to 208 Gallons. Inches Weight Inches Weight Inches lag Gallons in lag Gallons in lag Gallons to brim. pounds 1 to brim. pounds to brim 93 1 H 24 15 22J 29* 29 14 2 3 24* 16 24 30 30 14 3 4i 25" 17 25^ 32 36 15J 4 6 25 i 18 27 34 43 16^ 5 7J 26 19 281 35 48 17^ 6 9 26J 20 30 36 53 184 7 lOi 26a 21 3U 37 58 19i 8 12 27 22 33 38 63 20i 9 13i 271 23 34J 39 67 21 10 15 27* 24 36 40 71 2H 11 16i 27| 25 37i 45 104 22 12 18 28 26 39" 50 146 22i 13 191 28 V 27 40* 55 208 231 14 21 29' 28 42" Weight in pounds 43* 45 54 64* 72^ 79 i 87 94^ 100* 106* 156" 219 312 Copper Tubing. Weight of ihe usual thickness. When the inside diameter is \ of an inch, 3 ozs. J do , 6 ozs. ; I do., 8 ozs. ; | do., 10 ozs. jjer foot. I do. 5 ozs. ; 96 WEIGHT OP BEASS, COPPER, ETC. Brass, Copper, Steel, and Lead. Weight of a Foot. 1 BBASS. COPPER. STEEL. LEAD. Diamt'r Weight Weight Weight Weight Weight Weight Weight Weight aud Side of of of of of of of of ofSq're. Round. Square. Round. Square. Round. Square., Round. Square. Inches. Lbs. Lbs. Lbs. Lbs. Lbs. Lbs. Lbs. Lba. '. . .17 .22 .19 .24 .17 .21 . . .39 .50 .42 .54 .38 .48 . . .70 .90 .75 .96 .67 .85 .1 1.10 1.40 1.17 1.50 1.04 1.33 1 1.59 2.02 1.69 2.16 1.50 1.91 2.1G 2.75 2.31 2.94 2.05 2.61 1 2.83 3. GO 3.02 3.84 2.67 3.41) 3.87 4 93 IJ 3.58 45G 3.82 4,8G 3.38 4.34 4.90 6 25 li 4.4-2 5.63 4 71 6. 4.18 5.32 6.06 7 71 ll 5.35 6.81 5.71 7 27 5 06 6 44 7 33 9.33 G.3G 8.10 6.79 8.6J 6 02 7.67 8.72 11.11 7.47 9.51 7.94 10.15 7.07 9. 10.24 13.04 if 8.f.G 11.03 9.21 11.77 8.20 10.14 11.87 15.12 9.95 12.G6 10. Gl 13.52 9.41 11.98 13.63 17.30 2 11.32 14.41 12.08 15.38 10.71 13.63 15.51 19.75 2J 12.78 16.27 13.G4 17.36 12.05 15.80 17.51 22.29 4 14.32 18.24 15.29 19.47 13.51 17.20 19.63 25. ^ 15.96 20 32 17.03 21.69 15.05 19 17 21.80 27.80 2A 17.68 22.53 18.87 24.03 . 16.68 21.21 24.24 30.86 2 i 19.50 24.83 20.81 26.50 18.39 23.41 26.72 34.02 21.40 27.25 22.84 29.08 20.18 25.70 29.33 37.34: 23.30 29.78 24.92 31.79 22.06 28.10 32.05 40.81 3 25 47 32.43 27.18 34.61 24.23 30.60 34.90 44.44 Stool. We'njhl of a Foot in Length of Flat. Thick, Thick, Thick. Thict, Thick, Thick, Thick. Thick, Size. 1-4 in. 3-8tbB 1-2 iu. S-8the. Size, in. 1-4 iu. y-Hths. 1-2 iu. 5-8th8. in. Ib8. lbs. lbs. lba. lbs. lbs. IbH. lbs. .852 1.27 1.70 2.13 2.1 2.13 3 20 4.26 .5.32 H .958 1.43 1.91 2 39 n 2.34 3.51 4.68 5.85 1.06 159 2.13 2. 66 1 3 2.55 3.83 5.11 6.39 1.17 1.75 2.34 2.92 1 :M 2.77 4.15 5.53 6 92 1 1 1.27 1.91 2.55 3.19 ; ■A 2.98 4.47 r,.^H 7.45 1.49 2.23 2.98 3.72 3^} 3.19 4 79 6.38 7 98 2 1.70 2.55 3.40 4.26 4 3.40 5.10 6.80 8.52 2i 1.91 2.87 3H3 4.79 WEIGHT OF CAST IRON, COPPER, ETC. 97 Cast Iron. Weight of a Foot in Length of Flat Cast Iron. Width Thick, Thick. Thick. Thick, Thick, Thick, Thick. oflron l-4th in. 3-8ths in. 1-2 inch. 5-8ths in. 3-4ths in. 7-8ths in. 1 inch. Inc's. Pounds. Pounds. Pounds. Pounds. Pounds. Pounds. Pounds. 2 1.56 2.34 3 12 3.90 4.68 5.46 6.25 2i 1.75 2.63 3.51 4 39 5.27 6.15 7.03 2A 1.95 2.92 3.90 4.88 5.85 6.83 7.81 2f 2.14 3.22 4.29 5.37 6 44 7.51 8 59 3 2 31 3.51 4.68 5.85 7.03 8.20 9.37 H 2.53 3.80 5.07 6.34 7.61 8.88 10.15 3i 2 73 4.10 5 46 6.83 8.20 9.57 10.93 3f 2 93 4.39 5.85 7.32 8.78 10.25 11.71 4 3.12 4.08 6 25 7.81 9.37 10.93 12.50 4L 3.32 4.97 6.64 8.30 9.96 11.62 13.28 u 3.51 5.27 7. 03 8.78 lit. .54 12.30 14 06 n 3.71 5.56 7 42 9.27 11.13 12.98 14.84 5 3.90 5.86 7.81 9.76 11.71 13 67 15 62 5^ 4 10 6.15 8.20 10.25 12 30 14.35 16.40 54 4.29 644 8.59 10 74 12 89 15.03 17.18 5^ 4.49 6.73 8 98 11.23 13 46 15 72 17 96 6 4.68 7.03 9.37 11.71 14.06 16 40 18.75 Cast Iron, Copper, Brass, and Lead. Balls. Weight of Cast Iron, Copper, Brass, and Lead BaUs, fnmi 1 inch to 11 inches in diameter. Dia. C. Iron. Copper. Brass. Lead. Dia. In. C. Iron. Copper. Pounds Brass Pounds Lead. In. Pounds Pounds Pounds Pounds Pounds Pounds 1 .136 .106 .158 .214 7 46.76 57.1 54.5 73 7 n .46 .562 .537 .727 7J 57.52 70.0 67.11 90.0 2 1.09 1.3 1.25 1.7 8 69.81 85.2 81.4 110.1 91 2.13 2.60 2.50 3.35 8h 83.73 102.3 100.0 l;i2.3 3 3.68 4.5 4.3 5.8 9 99.4 121.3 115.9 156.7 H 5.84 7.14 6.82 9.23 9h 116 9 143 1.36.4 184 7 4 8.72 10.7 10.2 13.8 10 136.35 166.4 159.0 215.0 H 12 42 15.25 14.5 19.6 lOh 157.84 193.0 184.0 250.0 5 17.04 20.8 199 26.9 11 181.48 221.8 211.8 286.7 54 22.68 27.74 26.47 36.0 lU 207.37 253.5 242.0 327.7 6 29.45 35.9 34.3 46.4 12 235.62 288.1 275.0 372.3 6.^ 37.44 45.70 43.67 59.13 98 WEIGHT OF Cast iron. Cast Iron.- -WeirjUofa Foot in Length of Square and Round. SQUARE. KOUND. Size. Weight. Size. Inch. Weight. Size. Inch. Weight, Size. Inch Weight. Inch sq. Pounds. eq. Pounds. sq. Pounds. sq. Pounds. .78 4| 74.26 8 .61 4| 58.32 1 1.22 5 78.12 .95 5 61.35 'S 1.75 5J 82.08 1.38 5J 64.46 2.39 5i 86.13 B 1.87 51 67.64 3.12 H 90.28 1 2.45 51 70.09 1| 3.95 4 94.53 H 3.10 4 74.24 1, 4.88 bl 98.87 H 3.83 4 77.65 1 1 5.90 4 103.32 i| 4.64 5^ 81.14 J. i ' 7.03 4 107.86 U 5.52 84.71 1 ' 8 8.25 6 112.50 l| 6.48 6 88.35 1 3. 9.57 «1 122.08 l| 7.51 64^ 95.87 10.98 4 6| 132.03 1 8.62 4 103.69 2 12.50 142.38 2 9.81 111.82 2J 14.11 7 153.12 n 11.08 7 120.26 2i 15.81 n 164.25 2i 12.42 7\ 129. 21 17.62 74 175.78 21 13.84 H 138.05 24 19.53 n 187.68 2| 15.33 71 147.41 2| 21.53 8 200. 2| 16.91 8' 157.08 21 2;^. 63 8.V 212.56 2| 2| 18.56 8\ 167.05 2| 25.83 8i 225.78 20.28 8, 177.10 3 28.12 ^ 239.25 3 22.08 n 187.91 3J 30.51 9 253. 12 ^ 23.96 9' 198.79 3i 33. 9| 267.38 ^ 25.SI2 n 210. 31 35 59 94 282. n 27.95 9.i 221.50 ^1 38.28 -n 297.07 '.n 30.06 91 233 31 41.06 10 312. 5t) 3| 32.25 10 245.43 3| 43.94 10.1 328.32 31 34.51 H'i 257 86 3} 40.92 lo.l 314.53 3 J 30.85 lOA 270.59 4 50. \()\ 361.13 4 39.27 m 283.63 44 53.14 11 378.12 H 41.76 11 296.97 ^ 56.44 ll.i 395.50 4 44.27 11] 310.63 n 59.81 111 413.28 n 46.97 lU 321.. 59 63.28 11] 431.44 M 49.70 11:] 338 85 66.84 12 450. 4 52.50 12 353.43 4:{ 70 50 5.5.37 Cast Iron. — We'ujM of a Suj>e'ficial Fool from \ in 2 inches thick. Size. Weight Size. Weight.' Size. IllH. Weight. Size. Ids. Weight. Size. Weight. Ihb. PouudH IDB. Pounds PouiuIh PouiuIh Ina. Pounds . 9.37 fr 23.43 1 :t7.50 n 51.56 1? li- 65.62 . 14.06 28.12 u 42.18 u 56.25 70.31 18.75 I: 32.81 n 46.87 n 60.93 2 75. WEIGHT OF BOILER TUBES. 99 To Ascertain the "Weight of Wrought Iron, Copper, or Brass Tubes and Pipes per Lineal Foot. From, \ an Inch in Inttrnal Diameter to 6 Inches. Area of Area of Area of Area of Diam. Plate. Sq. Feet. Diam. Plate. Sq. Feet. Diam. Plate. Sq. Feet. Diam. Plate. Ins. Ins. Ins. Ins. Sq. Feet. ^ .1309 15-16 .3436 2J .7199 4.^ 1.1781 9-16 .1473 If .36 2i .7526 4| 1.2108 f .1636 1 7-16 .3764 3 .7854 4f 4| 1.2435 11-16 .18 u .3927 3^ .8181 1.2763 3-4 .1964 1| .4254 31 .8508 5 1.309 13-16 .2127 1| .4581 3| .8836 H 1.3417 i .2291 H .4909 3k .9163 4 1.3744 15-16 .2454 2 .5236 n .949 4 14072 1 .2618 2^ .5543 3| .9818 H 1.4399 11-16 .2782 2Jr .587 4 1.0472 5| 1.4726 u .2945 •2| .6198 • H 1.0799 5| 1.5053 13-16 .3105 2i .6545 4.V 1.1126 5| 1.5381 U .3272 2| 1 .6872 H 1.1454 6 1.5708 Application of the Table. When the Thickness of the Metal is given in the Divisions of AN Inch. To the internal diameter of the tube or pipe add the thickness of the metal ; take the area of a plate in square feet, from the table, for a diameter equal to the sum of the diameter and thick- ness of the tube or pipe, and multiply it by the weight of a square foot of the metal for the given thickness, and again by- its length in feet. Illustkation. — Required the -weight of 10 feet of copper tube 1 inch in circumference and I of an inch in thickness. 1 -|- 1 = 1^ = .2945 square feet for 1 foot of length. Weight of 1 square foot of copper^ of an inch in thickness = 5.781 lbs.; then, .2945 X 5.781 = 1.7025 lbs. When the Thickness of the Metal is given in Numbees of a WiEE Gauge. To the internal diameter of the tube or pipe add the thickness, multiply the sum by 3.1416, divide the product by 12, and the quotient will give you the area of the plate in square feet. Then proceed as before given. Illttstration. -Required the weight of 10 feet of coi^per pipe 2 inches in diameter, and No. 2 American wire gauge in thick- I16SS 2 + .25763 X 3.1416 — 12 = 2.25763 X 3.1416 -^ 12 = .591 square feet ; then, .591 X 11.G706 = G.b97 lbs 100 SIZE AND WEIGHT OF LEAD PIPE, ETC. Table showing the Thickness and Weight of Gal- vanized Sheet Iron. Dimensions of Sheet, 2 Feet tN Width by from G to 9 Feet IN Length. Wire Gauge. Weight per Sq. loot. Oz. Wire Gauge. Weight per Sq. Foot. Wire Gauge. Weight per Sq. Foot. Oz. Wire Gauge. Weight per Sq. Foot. No. No. Oz. No. No. Oz. 30 10 26 15 22 21 18 37 29 11 25 10 21 24 17 43 28 12 2i 17 20 28 16 48 27 14 23 19 19 33 U 60 Patent Improved Lead Pipe, Sizes and "Weight per ^Poot. J2 <3 In. Weight Per Foot lU d In. il fe (0 2 i lbs. oz. lbs. oz. In. lbs. oz. 6 1 •> 1 4 ^ 1 4 8 i i 1 8 2 10 it 2 2 4 12 ; • i 3 2 8 1 r? 8 13 3 1 8 n 1 4 8 i i 1 8 1 1 8 10 i ( 2 1 12 12 ( ( 2 12 2 14 ^ 12 2 8 1 4. 14 3 o5 -s "S i 1 ■a o 4 ^ .2f h XI 6 6 In. lbs. oz. In. 1 4 IJ ii 6 1^ n t k 2 8 3 2 it 3 8 t( ti 4 •41 M it 5 3 _o n. 3 3^ ^ •w a 3 8 4 fl t( 4 H. w~1 t ( 4 8 f^ ^ lbs. oz. 5 4 5 6 7 11 13 15 18 20 22 U Boston Lead Pipe, Sizes and Weight per Foot. >iln. Kin. %ln. 1 In. l^ in. l«In. IX in. 3 in. lbs. oz. 1 Ibe. 1 oz lbs. oz. IbH. oz. lbs. oz. ' lbs. oz. lbs. oz IbH oz. 10 1 2 12 1 1 1 8 2 4 3 5 3 10 4 12 12 3 1 6 1 12 2 8 3 12 4 3 5 8 13 1 12 2 2 13 4 4 5 2 7 12 1 4 2 4 2 G 3 3 4 10 1 8 3 2 2 11 3 15 6 1 11 3 14 :) 13 i 1 14 5 2 4 6 4 STRENGTH OP MATERIALS. 101 Slieet Lead.— Weight of a Square Foot, 21, 3, 3^, 4, ^, 5, G, 7, 8^, 9, 10 lbs. and upward. Comparative Strength and Weight of Ropes and Chains. a o Cm ^ u s 4i 5| 6i 7 8 8| 9i 03 o ^ .1 ft d d o 2 .^ T-l J3 -d o ■=< o d ■aa oj d d a -2 ^1 ^1 2 1 d d Q 2| 5 ^. 1 51 10 4| s 8 1 161 10| 5| y'n 10^ 2 10 in 7 14 3 51 12i 9| T^n 18 4 31 13 Hi # 22 5 2 133- 15 11 i 6 27 6 41 14% 19 II 32 7 7 15i 21 \l 37 8 135 16' Note. — It must be understood and also borne in mind, that, in estimating the amount of tensile strain to which a body is subjected, the weight of the body itself must also be taken into account ; for according to its position so may it approximate to its whole weight in tending to produce extension within itself; as in the almost constant application of ropes and chains to great depths, considerable heights, &c. STRENG-TH OF MATERIALS OF CONSTRUCTION. Materials of construction are liable to four different kinds of strain ; viz., stretching, crushing, transverse action, and torsion or twisting ; the first of which depends upon the body's tenacity alone ; the second, on its resistance to compression ; the third, on its tenacity and compression combined ; and the fourth, on that property by which it opposes any acting force tending to change from a straight line, to that of a spiral direction, the fibres of which the body is composed. In bodies, the power of tenacity and resistance to compression, in the direction of their length, is as the cross-section of their area multiplied by the results of experiments on similar bodies, as exhibited m the following tables. 102 BTRENGTH OP MATERIALS. Table showing the Tenacities, Resistances to Com- pression, and other Properties of the common Materials of Construction. Names of Bodies. Absolute Ash, Beech, Brass, Brick, Cast Iron Copper (wrought), Elm, Fir, or Pine, White, . »♦ " Red, . . . " " Yellow, Granite (Aberdeen), Gun-metal (copper 8, and tin 1 ), Malleable Iron Larch, Tenacity in lbs. per eq. Inch. Lead Mahogany, Honduras Marble, Oak, Eope( 1 in. in circum. ) 8teel, Stone, Bath, " Craigleith, . . . " Dundee, " Portland, . . . . Tin (cast), Zinc (sheet), 14,130 12,225 17,908 275 13,434 33,000 9,720 12,340 11,800 11,835 35,838 56,000 12,240 1,824 11,475 551 11,880 200 128,000 478 772 2,001 857 4,730 9,120 Uebistance to coinpreB- BioQ lu lbs per eq. iucti. Compared \, ith Cast Iron 8,548 10,304 562 86,397 1,033 2,028 5,375 5,445 10,910 5,508 8,000 6,000 9,504 5,490 6,630 3,729 Its strength 0.23 0.15 0.435 LO 0.21 0.23 0.3 0.25 0.65 1.12 0.136 0.096 0.24 0.25 Its ex- tL'Dsibility is 0.182 0.365 2.6 2.1 0.9 1.0 2.9 2.4 2.4 2.9 1.25 0.86 2.3 2.5 2.9 2.8 IIS stiffness Is 0.089 0.073 0.49 1.0 0.073 0.1 0.1 0.087 0.535 1.3 0.0585 0.038 0.487 0.093 0.75 0.5 0.25 0.76 Resistance to Lateral Presstire, or Transverse Action. The strength of a square or retangular beam to resist lateral pressurfi, acting in a perpendicular direction to its leugtli, is as the breadth and Sfpiarc f)f the depth, and inversely a,s the length; thus, a briiiii twic.' llK-br.'adthnfaiiotlicr, all other circumstaneeH being alike, eqnids twi(!(( the strength of tlie other; or twice tho depth e,200 .31 8,978 .39 7,980 .49 7,182 .61 14 13,HH3 .21 ii,90;i .28 10,112 .36 9,2.55 .46 8,330 .57 15 15,937 .19 13,0(50 .20 11,952 .34 10,(524 .43 9,5(52 .53 ir, 1H,12H .18 15, .530 .21 13,.1H4 .32 12,080 40 10,880 .5 17 20, .500 .17 17,. 500 .23 15,353 .30 13,(547 ..38 12,282 •47 18 22,932 .10 19,(550 .21 17/208 .28 15.700 .3(5 13 752 .44 N')TK 'PiiiH tiililc shnws tlw ^fittest Weight that rv(>r ou^jht to bf laiil iip'iii a Oram I'nr pcriiiunrnt Inud; imd if tlier(! \h\ any lia- bility to jerks, (!tc., aiuphi alUiwaiici' must be iiiadi'; also tlio w(;ii;lit of the beam itself must bo included, {ike Tables of Cast Iron. ) STHENGTH OP MATORI.VLS. 107 To find the wehjld of a cast iron beam of (jlo .n ulmensions. Rule. — Multiply the sectional area in inches by the length in feet, and by 3.2; the product equals the weight in lbs. Ex. — Required the weight of a uniform rectangular beam of cast iron, 16 feet in length, 1 1 inches in breadth, and 1 J inches in thickness. 11 X 1-5 X 16 X 3.2 = 844.8 lbs. To determine the dimetisioiis of a support or. column to hear, without sensible curvature, a given pressure in thi direction of its axis. Rule. — Multiply the pressure to be supported in pounds by the square of the column's length in feet, and divide the product by twenty times the tabular value of E; and the quotient will be equal to the breadth multiplied by the cube of the least thickness, both being exj)ressed in inches. Note 1. — When the pillar or support is a square, its side will be the fourth root of the quotient. Note 2. — If the pillar or column he a cylinder, multiply the tabular value of E by 12, and the fourth root of the quotient equals the diameter. Ex. 1. — What should be the least dimensions of an oak sup- port, to bear a weight of 2,210 lbs., without sensible flexure, its breadth being 3 inches and its length 5 feet? Tabular value of E = 105, 2240 X 52 ^^^ 20X1U5X3 = V «.86« = 2 05 inches. Ex. 2. — Required the side of a square piece of Riga fir, 9 feet in length, to bear a permanent weight of 6,000 lbs. Tabular value of E = 96, ^ 6000 X 92 ^ ,-r^ ... , and - = < v/ 253 = 4 inches nearly. Elasticity of Torsion, or Resistance of Bodies to Twisting. The angle of flexure by torsion is as the length and extensi- bility of the body directly, and inversely as the diameter; hence, the length of a bar or shaft being given, the power and the lever- age the power acts with being known, and also the number of degrees of torsion that will not aff'ect the action ol the machine, to determine the diameter in cast iron with a givsn angle of flexure. Rule — Multiply the power in poiinds by the length of the shaft in feet, and by the leverage in feet; divide the product by fifty-five times the number of degrees in the angle of torsion; and the fourth root of the quotient equals the shaft's diameter in inches. 103 STRENGTH OF MATERIALS. Ex —Required the diameters for a series of shafts 33 feet in length, and to transmit a power equal to 1,245 lbs., acting at the circumference of a wheel 2.} feet radius, so that the twist of the shafts on the application of the power may not exceed one degree. 1245X35X2.5 55X1 :=■< y 19a 1 = 6.67 inches in diameter. To determine the side of a square shaft to resist torsion loilh a given Jiexure. Rule. — Multiply the power in pounds by the leverage it acts •with in feet, and also by the length of the shaft in feet; divide this product by 92.5 times the angle of flexure in degrees, and the square root of the quotient equals the area of the shaft in inches. Ex. — Suppose the length of a shaft to be 12 feet, and to be driven by a power equal to 700 lbs , acting at one foot from the centre of the shaft — required the area of cross-section, so that it may not exceed 1 degree of flexure. 700 X 1 X 12 92.5 X 1 V- ^ •! v/ 90.8 = 9.53 inches. Relative Strength of Bodies to resist Torsion, Lead being 1. Tin 1.4 Copper 4.3 Yellow Brass . . 4.6 Gun-Metal 5.0 Cast Iron 9.0 Swedish Iron . . .9.5 English Iron. . . 10. 1 Blistered Steel .16.6 Shear Steel.. ..17.0 Sftr of Iron. — The average breaking weight of a bar of ■wrought iron, 1 inch scpiare, is 25 tons; its elasticity is destroyed, however, by about two-tifths of that weight, or 10 tons. It is extended, within the Uiuits of its elasticity, .t) lOO'Jfi, or one ten- thousandtli part of an inch for every ton of strain jxTsijuarc inch of sectional area. Ilcaice, the greatest constant load shouhl never exceed one-tifth of its breaking weight, or Stuns for every square inch of sectional area. The lateral strength of wrought iron, as compared with cast iron, is as 14 to 9. Mr. Barlow finds that wrouglit iron bars, 3 inches deep, 1-^ indies thick, and ^3 inches between the sup- ports, will carry 4^ tons. lir h I ffrx. -The greatest extraneous load on a square foot in about IJO pounds. Floors. Till! least load on a square foot is about 160 pounds. Itoofs. Covcn-d with slate, on a square foot. 51 i pounds. Jicti ins. When a beam is sii]qi(irt<'d in the miildlc and loaded at each ,'0 lbs Hempen cords, twisted, will support the following weights to the square inch of their section. \ inch to 1 inch thick, 8,746 lbs. ; 1 to 3 inches thick, 6,800 lbs. ; 3 to 5 inches thick, 5,345 lbs. ; 5 to 7 inches thick, 4,860 lbs. Tredgold gives the following rule for finding the weight in pounds which a hempen rope will be capable of supporting : Multiply the square of the circumference in inches by 200, and the product -will be the quantity sought. In the practical application of these measures of absolute strength, that of metals should be reckoned at one-half, and that of woods and cords at one-third of their estimated value. In a parallelopipedon of uniform thickness, supported on two points and loaded in the middle, the lateral strmqth is directly as the product of the breadth ii^to the square of the depth, and im ersely_ as the length. Let W represent the lateral strength of any material, estimated by the weight, h the breadth, and (/ the depth of its end, and I the distance between the points of support ; then If the parallelopipedon be fastened only at one end in a hori- zontal position, and the load be applied at the opposite end, W=/(i-5-:-4Z. It is to be observed that the three dimensions, b, d, and I, are to be taken in the same measure, und that h be so great that no lateral curvature arise from the weight ; / in each formula rep- resents the 1 iteral strength, which varies in differe-ut materials, and which must be learnt experimentallj'. A beam having a rectangular end, whose breadth is two or three times greater than the breadth of another beam, has a po-R-er of suspension respectively two or three times greater than it; if the end be two or three times deeper than the end of the other, the suspension power of that which has the greater depth exceeds the suspension power of the other four or nine times ; if its length be two or three times greater than the length of another beam, its power of suspension will be A or ^ respectively that of the other ; provided that in each case'the mode of suspension, the position of the weight, and other circumstances be similar. 112 STRENGTH OF MATERIALS. Hence it follows that a beam, one of whose sides tapers, has a greater power of suspension if placed on a slant than on the bi'oad side, and that the powers of suspension in both cases are in the ratio of their sides; so, for instance, a beam, one of whose sides is double the width of the other, will carry twice as much if placed on the narrow side, as it wovild if laid on the wide one. In a piece of round timber (a cylinder) the power of suspen- sion is in proportion to the diameters cubed, anil inversely as the length ; thus a beam %vith a diameter two or three times longer tl:an that of another, will carry a weight 8 or 27 times heavier respectively than that whose diameter is unity, the mode of faste dng and loading it being similar in both cases. The lateral strength of square timber is to that of a tree whence it is hewn as 10 : 17 nearly. A considerable advantage is frequently secured by using hollow cylinders instead of solid ones, which, with an equal ex- penditure of materials, have far greater strength, proviiled only that the solid part of the cylinder be of a sufficient thickness, and that the workmanship be good; esi:)ecially that in cast metal beams the thickness be uniform and the metal free from flaws. According to Eytelwein, such hollow cylinders are to solid ones of equal weight of metal as 1.212 : 1, when the inner semi-diame- ter is to the outer as 1 : 2 ; according to Tredgoldas 17 : 10, when the two semi-diameters are to each other as 15 : 25; and as 2 : 1, when they are to each other as 7 : 10. A method of increasing the suspensive power of timber sup- ported at both ends, is, to saw down from ^ to }, of its depth, and forcibly drive in a wedge of metal or hard wood, until the timber is slightly raised at the middle out of the horizontid line. By experiment it was found that the suspensive jiower of a beam thus cut ^ of its depth was increased l-19th, when cut J it was incn^ased l-29th, and when cut i| through it was increased'l-87th. The force required to crush a body increases as the section of the body increases ; and this quantity being constant, the re- sistance of the body diminishes as the height increases. According to Eytelwein's experiments, tlie strength of columns or timbers of rectangular form in resisting compression is, as 1. The cube of their thickness (the lesser dimension of their section). 2. As the breadth (the greater dimension of their section). 3. Inversely as the sipiare of their length. Cohesive Power of Bars of Metal one inch square, in Tons. Iron Swedish bur 29.20 " liuRsiiin bur, 2r).70 '• Euglish bar 25.00 Steel cast r>'.}.'X] " blittti-red, r,'.).r.i " sheer, Cr,.97 Copper, wrought, 1.').08 (Jnn-mctal 16.23 Copper, cast, 8.51 I5ra.ss, cast, yellow 8.01 Iron, ciist, 7.H7 Tin, cast, 2.11 STRENGTH OF MATERIALS. 113 Relative Strength of Cast and Malleable Iron. It has been found, in the course of the experiments made by Mr. Hodgkinson and Mr. Fairbairn, that the average strain that cast iron will bear in the way of tension, before breaking, is about seven tons and a half per square inch ; the weakest, in the course of 16 trials on various descriptions, bearing 6 tons, and the strongest 9| tons. The experiments of Telford and Brown show that malleable iron will bear on an average 'Al tons; the weakest bearing 24, and the strongest 29 tons. On approach- ing the breaking point, cast iron may snap in an instant, with- out any previous symptom, while wrought iron begins to stretch with half its breaking weight, and so continues to stretch till it breaks. The experiments of Hodgkinson and Fairbairn show also that cast iron is capable of sustaining compression to the ex- tent of nearly 50 tons on the square inch ; the weakest bearing 30 J tons, ard the strongest 60 tons. In this respect, malleable iron is much inferior to cast iron. With 12 tons on the square inch it yields, contracts in length, and expands laterally ; though it' will bear 27 tons, or more, without actual fracture. Eennie states that cast iron may be criished with a weight of 93,000 lbs. and brick with one of 562 lbs., on the square inch. Strength of Beams. SOLID, EECTANGULAU, AND BOUND : TO FIND THEIR STKENGTH. t^quare and, Eedangular. (Depth ins. )2X Thickness ins. m i . -vt t. i- _i x ^ — i- ^ \ — 7 X Tab r No. = Breaking wt., tons. Length, ft. Round. (Diameter ins.l^ Length in ft. X Tabular No. = Breaking weight, tons. Hollow. (Outsidedia.ins.)3-(Insidedia.ins.) ^ ^^^^^^^^ ^.^ ^^^^^^^ Length, ft. ing weight, tons. Thicknees not exceeding j 1 in. for iron 3 in. for wood 2 in. for iron 3 in. for iron 6 in. for wood 12 in., wood Round. Cast and wrought iron Teak and greenheart I Fir and English oak I .8 .28 .14 114 STRENGTH OF MATERIALS. Square and Rectangular. Cast and wrought iron Teak and greeuheart ....... Pitch pine and Canadian oak Fir, red pine, and English oak .1 .36 .85 .32 .7 .26 .25 .22 .18 .18 .16 .13 To FIND THE BkEAKING WeIGHT IN PoUNDS USE THE TaBULAB NUMBEK BELOW. m • 1 1 T 1 1 in. for iron Thickness not exceeding \ Uiu.foj-wood 2 in. for iron 6 in. for wood 3 in. for iron 12 in., wood Square and Rectangular. Iron Teak Fir and oak . 2,240 1,900 1,570 800 710 570 100 355 285 Round. Iron Teak Fir and oak Though wronght and cast iron are represented in these rules as of equal strength, it should be observed that wliiUi a cast iron Vmr 1 inch X 1 inch X 1 loot inch h)ng, of average (juality, will l)reiik with one ton, a siinil.ir Inir of wrouglit iron only loses its elasticity, and deflects l-ldth of an inch, yet as it can only carry a further wiiglit by destroying its shape and increasing the de- flection, it is best to calculate on the above basis: DldrctH ( 1-16 with Iton. L'-^ 1-H " A wrought iron ])ar 1 inX 1 in X 1 ft. Gin. long l2U2 2\ " The above rule gives the weight that will break the beam if put on the middle. If tln^ weight is laid ((lually all over, it would ri'(iuire dou])l(! the weiglit to lireak it. A biiini should not be loaded with more than 1-3 of tho break- ing weight in any (-ase, and as a general rule not with more than 1-4. for the ])ur|)oses of machinery not with more than 1-6 to 1-10, depending on circumstuuceB. STRENGTH OF MATERIALS. To FIND THE PeoPER SizE FOB ANY GIVEN PURPOSE. Hectangidar. Weight X Length, ft 115 Tabular No. X 3 or 4 or 6, &c , according to circumstan- ces = B D^ ins. Round. ■V 5 / Weight X Length, ft. Tabular No. X 3 or 4 or 6, «tc., according to circum- stances =^ diiim. ins. Solid Columns. Fail by crushing with length under 5 diameters Principally by crushing from 5 to 15 " Partly by crushing, partly by bending, from. 15 to 25 " Altogether by bending above 25 " Cast iron of average quality is crushed with . .49 tons per sq. in. Wr'ght iron of average quality is crushed with.. 16 " " Wrought iron is permanently injured with. . .12 " " Oak wrought is crushed with 4 " " Deal wrought is crushed with 2 " " The comparative strength of dififerent columns, of diflferent lengths, will be seen very clearly from the following table derived from experiments by Mr. Hodgkinson : Wrought Iron Bars. Proportion of Length to Thickness. Gave way with Square. Length. ins. ft. ins. 1 X 1 7.i 7^tol 21.7 tons per sq. inch. (( 1 3 15 tol 15.4 (( 2 6 30 to 1 11.3 (( 5 60 tol 7.5 it 7 6 90 tol 4.3 ^ X ^ 5 120 tol 2.5 (( 7 6 180 to 1 1. To FIND THE Strength of any Wrought Iron Column with Square Ends. Area of column sq. inches X tons per inch corresponding to pro- portion of length, as per table above = Breaking weight, tons. If the ends are rounded, divide the final result by 3 to find the breaking weight. In columns of oblong section, the narrowest side must always be taken in calculating the proportion of height to width. 116 STRENGTH OF MATERIALS. To FIND THE Strength of Round Columns exceeding 25 diametebs IN LENGTH — Mb. HoDGKINSON's KuLE. ■^ r-^- — ^ X Tabular No. = Breaking weicht, tons. (Length, ft.)'-' & fa > "Wrought iron Cast iron . Dantzic oak. , Ked deal Rounded or Movable Square Ends. Ends. 77 26 U 15 4.5 L7 3.3 L2 A column should not bo loaded Avith more than 1-3 of the breaking weight in any case, and as a general rule, not with more than 1-4; for purposes of machinery not with more than 1-6 to 1-10, according to circumstances. Tables of Powers for the Diameters and Lengths of Columns. Diameter. 3.G Power. Diameter. 3.6 Power. 1 in. 1. 7 in. 1,102.4 2 23 k 1,251. ] ■ 4.3 i 1,413.3 7.5 i 1,590.3 2 12.1 8 1,782.9 \ 18.5 i 1,991.7 27. t 4 2,217.7 i 38.16 2,461.7 3 52.2 9 2, 72}. 4 i 6i).63 \ 3,006.85 90.9 3,309.8 116.55 1 3,634.3 4 147. 10 3,981.07 \ 182 9 i 4,351.2 I 224.68 1 4.741.5 i 272.96 t 1 5,165. 5 328.3 11 5,610.7 r 391.36 \ 6,083.4 1 462.71 6,584.3 1 543.01 7,114.4 6 632.91 rj' 7,674.5 1 : 733. 1 1 1 ' 844.28 967.15 Length. 1-7 Power. 1 1. 2 3.25 3 6.47 4 10.556 5 15.426 6 2L031 7 27.332 8 34.297 9 41.9 10 50.119 11 58.934 12 68.329 13 78.289 14 88.8 15 99.85 16 111.43 17 123.53 18 136.13 19 149.24 20 162.84 21 176.92 22 191.48 23 206.51 21 222. STRENGTH OF MATERIALS. 117 Hollow Columns, Hollow columns fail principally by crushing, provided the length does not exceed 25 diameters ; indeed the length does not appear to aflfect the strength much till it exceeds 50 diameters. The comparative strength of different forms and of different thicknesses will appear so distinctly from the experiments below, made by Mr. Hodgkinson, that no difficulty will be found in ascertaining the strength due to any size or form of column that may be required. Square Columns of Plate Iron eiyeted. Columns 10 feet inches long. Size. Thick- Proportion of uess. Thickness to Width. 4 in. X 4 in. .03 iS (< .06 ;^g (( .1 io <( .2 h 8 in. X 8 in. .06 I33 t< .14 -h (t .22 /e (( .25 vh Proportion of Length to Width. 30 to 1 15tol Break'g w'ght Tons per eq. m. of section. 4.9 8.6 10. 12. 6. 9. 11.5 12. Column SJeet inches long. 18 X 18 .5 ^\ practically. 5.4 to 1 13.6 Column 10 feet inches long, with cells. Sin. X 8 in. .06 J- of width of cells. 15tol 8.6 To find the Strength of any Hollow Wrought Iron Column. Q • s/ /'tons per inch, corresponding to the pro-\ &ec. area, sq. ins. X V portions of length and thickness to width j = Breaking weight, tons. Columns of Oblong Section. The strength of these may be ascertained by the same rule as that of square columns. The smallest width being taken in cal- culating the proportion of height to width, while the longest side must be taken into consideration in calculating the proportion of thickness to width. 118 STiiENGTH OF MATERIALS. Column 10 feet incJies long. Size. Thick- ness. Proportion of Thickness to greatest Width. Proportion of Length to least ■Width. Breaking wt. tons p»r sq. in. of seo. 8 in X 4 in. .06 3;f5 30 to 1 6.78 Bound Columns of Piate Ibon Riveted. Columns 10 feet inches in length. Dia- Thick- meter. ness. 1 n. .1 2 .1 'if, .1 n .24 n .21 3 •15 4 .15 6 .1 6 .13 Proportion of thick- ness to Diameter. ao 1 la 1 is ^^ 1 D- _i- Breaking Proportion | Weight of length to Tons per Diameter. 80 to 60 to 48 to 48 to 48 to 40 to 30 to 20 to 20 to sq. inch 6.5 10.35 13.3 9.6 9.9 12.36 12.34 15. 18.6 Same Columns Reduced in Length. Breaking Weights. Tons pi r square inch. 5 ft. in. long '3.9 .4.8 15.6 15.6 13. 13. 13. 17. ! ft. 6 in. long 5.8 16.5 16.3 16. 17. 16.5 18.6 It would Rcem from this that a thickness of 1-48, or \ inch in thickness for every foot in iliivmeter, is a good proportion for this kind of column. It will be seen from these cxporiments, that it is the propor- tion of thickness to the width of cell which regulates the strength •vitliin certain limits of height. And that a tliickncss of 1 :iO or J inch for every 4 inches in width will give the highest result practicable for square columns. Crano. Tlin strains on tlm i)rinci])iil j)iirts can bo ascertained with (^.-•yit f'UKi' in the f«. STRENGTH OF MATERIALS. 121 Elements connected with the Tensile Resistance of various Substances. Substances. Beech 'Jast iron, English " American Oak Steel plates, blue tempered " wire , Yellow pine , Wrought iron, ordinary " Swedish " English " " American " " wire, No. 9, unannealed " annealed... fl _. a , , •2 Jv, '3 2 eams of castor wrought iron tlio flanges should be propor- tionate to the relative crushing and tensile resistances of the mo- t creased. Girders of cast iroa, up to a span of 40 feet, involve a less cost than of wrought iron. Cast iron beams and girders should not be loaded to exceed one- fifth of their breaking weight; and when the strain is attended with concussion and vibration, this proportion must be increased. Simple cast-iron girders may be made 50 feet in length, and the best form is that of Hodgkihson; when subjected to a fixed load, the flange should be as 1 to 6, and when to a concussion, etc., as 1 to 4, The forms of girders for spaces exceeding the limit of those of simple cast iron are various; the principal ones adopted are those of the straight or arched cast-iron girders in separate pieces, and bolted together — the Trussed, the Bow-string, and the wrought iron Box and Tubular. A StraiijM or Archeil Girder is formed of separate castings, and is entirely dependent ujion the bolts of connection for its strength. A Trussed or Bow-siring Girder is made of one or more castings to a single piece, and its strength depends, other than upon the depth or area of it, iipon the proper adjustment of the tension, or the initial strain, upon the wrought iron truss. A Box or Tubular Girder is made of wrought iron, and is best constructed with cast iron tops, in order to resist compression; this form of girder is best adapted to afford lateral stiffliess. Floor Beams, Girders, etc. The condition of the stress borne by a floor beam is that of a beam supported at both ends and uniformly loaded; and from the irregularity in its loading rmd unloading, and from the necessity 134 STRENGTH OF MATERIALS. of its possessing great rigidity, it is impracticable to estimate its capacity other thaa as a beam having the weight borne upon the middle of its length. To Compute the Depth of a Floor Beam. When the Length ami Breadth are rjiv n, and the Distance hdween th« CetUres of the Beam is One Foot. EuLE.— Divide the product of the square of the length in feet and the weight to be borne in pounds per sqiiare foot of floor, l)j' the product of -4 times the breadtli and the value of the material, and the square root of the quotient will give the depth of the beam in inches. Example. — A white pine beam is two inches wide, and 12 feet in length between the sup{)orts; what should be the depth of it to support a weight of 175 lbs. per s(|uare foot? 12- y 175 „ . ' = 105, and y 105 = 10.25 ins. 2X4X30 ^ When the Distance Ijetween the Cn^res of the Beam is greater or less than One Foot. EuLE. — Divide the product of the square of the depth for a beam, when the distance between the centres is one foot, by the distance given in inches by 12, and the square root of the quo- tient will give the depth of the beam in inches. Example. — Assume the beam in the preceding case to be set 15 ins. from the centres of its adjoining beams, what should be its depth ? 10.25y 15 ^ j2^ 25, and v' 131.25 = 11.45 ins. Header and Trimmer Beams. The conditions of the stress borne or to be provided for by them are as follows : Header or Trimmer beams support half of the weight of and upon the tail beams inserted into or attached to them. Trimmer Beams support, in addition to that borne by them di- rectly as a floor beam, each half tlu; wciglit on the headers. The stress, therefore, ujiou a header is due directly to its length, or the number of tail beams it supports; and the stress upon tlio trimmer beams is that of their own stress as a floor beam, and half of the weight upon the header supjiorted by them. Note. -The distance between the sup])ort of the trimmer beams and the point of connection with the header does not in anywise afry thc! header reduced, an.02x.rA5 = 1.040 2.23X.31 = .72 5x.3=1.6 a o ■*^ o « Sq. Ins. 1.77x,3'J = .G9 2 02x 515 =1.040 r,.(;7x 06 = 1.4 jx.3=1.5 Eectangii- lar PriBm, Open Beam, ^^ Square liJ Prism, WJ Column, ,A. Square "^M^ Prism, anjilfi up. 5x.5=.25 1.5x5= .75 4x2=8 5.1x2.33 = ll.d8 1 005 X.98 .995x1.01 1.005 x.98 .771x1.51 1.507 X 74 1.525 X. 78 23.9x3.12 = 74.56 l..'=x.6= .75 .5x5 = .25 12.1x2 07 = 25 04 2.08 .994 1 005x99' 1.00.- In. .29 .51' .206 .36i .365 3.3 .5 ■d u 3 Cm o Qi Q .995 x.l 1.005 X. 99 .771x1.5 1.507 X.74 .995 1.00 .771 1 .507 1. 525 X. 78: 1.525 11.02 1.122 1.443 In. 5.125 2.02 5.125 1.56 1.56 56.1 4.t 4.t 4. 30.5 2.012 2./51 3.01 4 4 04 4.04 4.07 1.02 1.122 1.443 ■a o si -a 03 In. 1.77 2.02 6.67 5. 5. 23.9 1.5 1.5 a o OQ c 11.1 994 005 995 1 005 Sq.I. 2.82 2 59 6.23 1.96 1.96 183.5 1. 1. 12. 90.8 2.025 I 98 1.9S 5§ '© VI a a . ■3;:: § Lbs. 301-'>0 10276 117450 7280 2360 80G624f 19980 7252 g.a Lbs a> bo 3 a s ■"■ >■ Lbs 10768 6100 1900 3952 188.J2 3714 :213 43958 19980 7252 3^600 2800 479380052795 9440 4662 .771 2.-2. 1.. 507 2.23 1.525 2.35 1 02 1.122 1.03 .989 1.443 1.041 12340 154211 2170.5 2.-)705 25735 30000 263.=. 2370 2269 6232 7710 10992 11070 11540 12689 i6S0 2350 760 1200 .5000 1800 700 1700 2350 2460 2550 2700 2750 2850 3100 2552; 2500 2396 2150 2182 1500 ♦ Horizontal yreb. t Deptti of opening, 3 J iicheB. 136 STRENGTH OF MATERIALS. General Deductions. In cast iron, the permanent deflection is from one-third to one-quarter of its breaking weight, and the deflection should never exceed one-third of the ultimate deflection. All rectangular bars of wrought iron, having the same bearing length, and loaded in their centre to the full extent of their elastic power, will be so deflected, that their deflection, being multiplied by their depth, the product will be a constant quan- tity, whatever may be their breadth or other dimensions, pro- vided their lengths are the same. The heaviest running weight that a bridge is subjected to is that of a locomotive and tender, which is equal to 1.5 tons per lineal foot. Girders should not be deflected to exceed the one fortieth of an inch to a foot in length. In cast iron, the one-twentieth to one-thirtieth of the breaking weight will gi\ e a visible set. When a load on a girder is supported by the bottom flange of it alone, it produces a torsional strain. A continuous weight, equal to that a beam, etc., is suited to sustain, will not cause the deflection of it to increase unless it is subjected to considerable changes of temperature. The heaviest load on a railway girder should not exceed one- sixth of that of the breaking weight of the girder when laid on at rest. Deflection consequent upon Velocity of the Load. — Deflection is very much increased by instantaneous loading; by some authorities it is estimated to be doubled. The momentum of a railway train in deflecting girders, etc., is greater than the eff"ect from the dead weight of it, and the de- flection increases with the velocity. Exi)erimcnts made by the Commissioners of Railway Structures of 1849, showed that a i)assing load produced a greater efiect on a beam than a load at rest. A carriage was moved at a velocity of 10 miles per hour; the deflection was .8 inch, and when at a velocity of 30 miles' the do- fl(H;tion was \\ inches. In this case, 4 l.'JO lbs. would have boon the breaking weight of the bars if applied in their middle, but 1,778 lbs. -would have broken them if pa.ssed over them with a velocity of 30 miles per hour. Cast iron will bend to one-third of its ultimate deflection with less than one-tliird of its ])reaking weight if it is laid on gnidually, and but one-sixth if laiil on rapidly. When motion is given to the load on a beam, etc., the point ol greate>it (lefb'ction does not remain in the centre of the beam, etc., as beuiMS broken by a travelling load are always fractured at points beyond their centreH, nrul oft«!n into several jiieces. Chilled bars of oust iron deflect more readily than unchillod. STRENGTH OF MATERIALS. 13'< Kesults of Experiments on the Subjection of Iron Bars to Continual Strains. Cast iron bars subjected to a regular depression, equal to the deflection due to a load of one-third of their statical breaking weight, bore 1U,(jOO successive depressions, and when broken by statical weight gave as great a resistance as like bars subjected to a like deflection by statical weight. Of two bars subjected to a deflection equal to that carried by half of their statical breaking weight, one broke with 28,602 de- pressions, and the other bore 30,000, and did not appear weaken- ed to resist statical pressure. Hence cast iron bars will not bear the continual applications of one-third of their breaking weight. A bar of wrought iron, 2 inches square and 9 feet in length be- tween its supports, was subjected to 1(10,000 vibrator}' depressions, each equal to the deflection due to a load of tive-ninths of that which permanently injured a similar bar, and their depressions only produced a permanent set of .015 inch. The greatest deflection which did not produce any permanent set was due to rather more than one-half the statical weight, which permanently injured it. A wrought-iron box girder 6x6 inches and 9 feet in length, was subjected to vibratory dejiressions, and a strain correspond- ing to 3,762 lbs., repeated 43, 370 times, did not produce any ap- preciable effect on the rivets. Mr. Tredgold, in his experiments upon cast iron, has shown that a load of 30') lbs., suspended from the middle of a bar 1 inch square and 34 inches between its siipports. gave a deflection of .16 of an inch, while the elasticity of the metal remained im- impaired. Hence a bar 1 inch square and 1 foot in length will sustain 650 lbs., and retain its elasticity Torsional Strength. The Torsional Strength of any square bar or beam is as the cube of its side, and of a cylinder as the ciibe of its diameter. Hollow cylinders or shafts have greater torsional strength than solid ones containing the same volume of material. The Torsional Awjh of a bar, etc., under equal pressures will vary as the length of the bar, etc. Hence the torsional strength of bars of like diameters is inversely as their lengths. The strength of a cylindrical prism compared to a square is as 1 to .85. When a bar, beam, etc., having a length greater than its diameter, is subjected to a torsional strain, the direction of the greatest strain is in the line of the diagonal of a square, and if a square be drawn on the surface of the bar, etc., in its primitive form, it will become a rhombus by the action of the strain. 138 STBENGIH OF MATERIALS. To Compute the Diameter of a Square or Bound Shaft, etc., to resist Torsion. KuL,E. — Multiply the extreme of pressure ui>on the crank-pin, or at the pitch-line of the pinion, or at the centre of effect upon the blades of the wheel, etc., that the shaft may at any time be subjected to, by the length of the crank or radius of the wheel, etc., in feet; divide their product by the value, and the cube root of the quotient will give the diameter of the shaft or its journal in inches. Example. — What should be the diameter for the journal of a wrought-iron water-wheel shaft, the extreme pressure upon the crank-pin being 59,4.00 lbs., and the crank 5 feet in length? ?^i^?^^ = 2,376, and V 2,276 = 13.31 inches. 125 When two Shajts are used, as in Sieamrvessels loHh one Engine, etc Uttle. — Divide three times the cube of the Cameter for one shaft by four, and the cube root of the quotient T.ill give the di- ameter of the shaft in inches. Example. — The area of the journal of a shaft is 113 inches; what should be the diameter, two shafts being used ? Diameter for area of 113 = 12. Then A>li^ =. 1,296, and' s/ 1,296 = 10.9 inches. Note. — The examples here given are deduced from instances of successful practice; where the diameter has been less, fracture has almost universally taken place, the strain being increased beyond the ordinary limit. When the work to be performed is of a regular character, and the stress is consequently uniform, the proportion of J may be reduced to f. Kelative Values of Diameters. When shafts of less diameter than 12 inches are required, the values here given may be slightly reduced or increjised, accord- in" to the quality of the iron and the ngth ; and when having equal lengths, by an increase in diameter they increase in stiff- ness in a greater proportion than in strength. The stress upon a shaft from a weight upon it is jiroportioiial to the product of the parts of the shaft multiplied into I'ach other. Thus, if a shaft is 10 feet in length, and a weight ui>on the centro of gravity of the stress is at a point 2 feet from one end, the parts 2 and 8, multiplied together, are equal to 16; but if the weight or stress were ai)piied in the middle of the shaft, the parts 5 an 1 &, multiplied together, would produce 2"i. The ends of a sliaft having to sni)])()rt the whole weight, tho end which is nearest the weight lias to su])])ort the greatest ])ro- portion of it, in the inverse projjortion of the distance of tho weight from the end. Ibnce, when a shaft is loaded in the middle, each of the journals or gudgeons has half the weight or HtreKS to SUp])()rt. When the ion I upon a shaft in uniformlv distributed over any imrt of it, it is cousidered an united in tlie middle of that part; WOOD, TIMBER, ETC. 141 and if the load is not tmiformly distributed, it is considered as united at its centre of gravity. When the transverse section of a shaft is a regular figure, as a square, circle, etc., and the load is applied in one point^ in order to give it equal resistance throughout its length, the curve of the sides becomes a cubic parabola; but when the load is uniformly distributed over the shaft, the curve of the sides becomes a semi- cubical parabola. The deflection of a shaft produced by a load which is uniformly distributed over its length is the same as when five-eighths of the load is applied at the middle of its length. The resistance of the body of a shaft to lateral stress is as its breadth and the square of its depth; hence the diameter will be as the product of the length of it and the length of it on one side of a given point, less the square of that length. WOOD, TIMBER, ETC. Selection of Standing Trees.— Wood grown in a moist soil is lighter and decaj's sooner than that grown in dry, sandy soil. The best timber is that grown in a dark soil intermixed with gravel. Poplar, cypress, willow, and all others which grow best in a wet soil, are exceptions. The hardest and densest woods, and the least subject to decaj', grow in warm climates, but they are more liable to split and warp in seasoning. Trees grown upon plains or in the centre of forests are less dense than those from the edge of a forest, from the side of a hill, or from open ground. Trees (in the U. S. ) should be selected in the latter part of Jiily or first part of August; for at this seasor the leaves of the sound, healthy trees are fresh and green, while those of the un- sound are beginning to turn yellow. A sound, healthy tree is recognized by its top branches being well leaved, the bark even and of a uniform color. A rounded top, few leaves, some of them turned yellow, a rougher bark than common, covered with para- sitic plants and with streaks or spots upon it, indicate a tree upon the decline. The decay of branches and the separation of bark from the wood are infallible indications that the wood is impaired. Fellinq Timber, — The most suitable time for felling timber is in midwinter and in midsummer. Recent experiments indi- cate the latter season and in the month of July. 142 WOOD, TIMBER, ETC. A tree should be allowed to attaia full maturity before being felled. Oak matures at 75 to 100 years and upward, according to circumstances. The age and rate of growth of a tree are indi- cated by the number and width of the rings of annual increase which are exhibited in a cross-section. A tree should be cut as near to the ground as practicable, as the lower part furnishes the best timber. r>ressut(/ Thiibev. — As soon as a tree is felled, it .should be stripped of its bark, raised from the ground, the sap-wood taken oflF, and the timber reduced to its required dim nsions Inspection of Timber.— T\\e qua ity of wood is in sorne degree indicated by its color, which should be nearly uniform in the heart, a little deeper toward the centre, and free from sudden transitions of color. White spots indicate decay, 'i'he sap-wood is known by its white color; it is next to the bark, and very soon rots. Defects of Titnher, — Wind-shakes are circular cracks sep- arating the concentric layers of wood from each other. It is a serious defect. Splits, cJieelis, and craefcs, extending toward the centre, if deep and strongly marked, render the timber unfit for use, unless the purpose for which it is intended will admit of its being split through them. JBrdsh-ivood is generally consequent upon the decline of the tree from age. The wood is porous, of a reddish color, and breaks short, without splintti-s. liolted timber is that which has been killed before being felled, or which has died from other causes. It is objectionable. Knottfl timber is that containing many knots, though sound; usually of stunted growth. Twisted wood is when the grain of it winds spirally; it is unfit for long pieces. Drtf-rot. — This is indicated by yellow stains. Elm and beech are soon afiected if left with the bark on. Lttrt/e or decayed hiiots injuriously affect the strength of timber. Seasoning and Preserving Timber. Timber freshly cut contains about 37 to 4 > per cent, of liquids. ]5y exposure to the air in seasoning (me year, it loses from 17 to 25 per cent., and when seasoned it yet retains from 10 to 15 per cent. Timber of largo dimensions is improved and rendered less lia- ble to warp and crack in being seasoned by immersion in water for some weeks Kor the purpose of s asoning, timber should 1«' juled under shelter and kei)t dry; it should have a free circulation of air about it, without being exposed to strong currents. The boUom jiiece should be pla<;(' 1 Upon skids, which should b(! free from decay, raised nf)t less tlian t'vo f 'et from the; ground; a space of an inch shoul I intervene bi-tween the pieces of the same liori- WOOD, TIMBER, ETC. - 143 zontal layers, and slats or piling-strips placed between cacli layer, one near each end of the pile and others at short distances. in order to keep the timber from winding. Tliese strips shoul 1 be one over the other, and in large piles should not be less than one inch thick. Light timber may be piled in the upper portion of the shelter, heavy timber upon the ground floor. Each pile should contain biat one description of timber. The piles should be at least 2.^ feet apart. Timber should be repiled at inter^-als, and all pieces indicat- ing decay should be removed, to prevent their affecting those ■which are still sound. 1 imber houses are best provided -with blinds, -which keep out rain and snow, but which can be tiirned to admit air in fine ■weather, and they should bo kept entirely free from any pieces of decayed ■«'ood. The gra lual mode of seasoning is the most favorable to the strength and durability of timber, but various methods have been proiDosed for hastening the process. For this purpose, steaming timber has been applied ■with success ; and the results of experiments of various processes of saturating timber M'ith a solution of corrosive sublimate and antiseptic fluids are very satisfactory. This process hardens and seasons ■wood, at the same time that it secures it from dry-rot and the attacks of ■worms. Kiln-drying is servicealle only for boards and pieces of small dimensions, and is apt to cause cracks and to impair the strength of -vs'ood, imless performed very slowly. Charring or painting is highly injiirious to any but seasoned timber, as it effectually prevents the drying of the inner part of the wood, in consequence of which fermentation and decay soon take place. Timber piled in badly-ventilated sheds is apt to be attacked ■with the common-rot. The first outward indications are yello^w spots upon the ends of the pieces, and a yellowish dust in the checks and cracks, particularly where the pieces rest upon the piling-strips. Timber requires from two to eight years to be seasoned thor- oughly, according to its dimensions. It should be worked as soon as it is thoroughly dry, for it deteriorates after that time. Oak timber loses one-fifth of its weight in seasoning, and about one-third of its weight in becoming perfectly dn'. Seasoning is the extraction or dissipation of the vegetable juices and moisture, or the solidification of the albumen. When wood is exposed to currents of air at a high temperature, the moisture evaporates too rapidly and the wood cracks; and when the teraperatiire is high and sap remains, it ferments, and dry-rot ensues. Timber is subject to common-rot or dry-rot, the former occa- sioned by alternate exposure to moisture or dryness. The prog- ress of this decay is from the exterior; hence the covering of the surface with paint, tar, etc. , is a preservative. Painting and charring green timber hastens its decay. Di'U or Sfip rot is inherent in timber, and it is occasioned by the 2-)utrefaction of the vegetable albumen. Sap wood contains a large proportion of fermentable elements. Insects attack wood 114 • WOOD, TIMBER, ETC. for the sugar or gum contained in it, and fungi subsist Tipon the albumen of woocl; hence, to arrest dry-rot, the albumen must be either extracted or solidified. In the seasoning of timber naturally there is required a period of from 2 to 4 years. Immersion in water facilitates seasoning by solving the sap. The most effective method of preserving timber is that of ex- pelling or exhausting its fluids, solidifying its albumen, and in- troducing an antiseptic liquid. The strength of impregnated timber is not reduced, and its re- silience is improved. In desiccating timber by expelling its fluids by heat and air, its strength is increased fully 15 per cent. In coating unseasoned timber with creosote, tar, etc., the fluiJs are retained, and decay facilitated thereby. When timber is saturated with creosote, tar, antiseptics, etc., it is ;.lso preserved from the attack of worms. Jarrow wood, from Australia, is not subjocted to their attack. The condition of timber, as to its soundness or decay, is readily recognized when struck a quick blow. Timber that has been for a long time immersed in water, when brought into the air and dried, becomes brashy and useless. When trees are barked in the spring, they should not be felled until the foliage is dead. Timber cannot be seasoned by either smoking or charring; but when it is to be used in locations where it is exposed to worms or to produce fungi, it is proper to smoke or char it. Timber may be partially seasoned by being boiled or steamed. Impregnation of Wood. The several processes are as follows : K}/(lit, 18:52. Saturated with corrosive sublimate. Solution 1 lit. of chloride of mercury to 4 gallons of water. Jiuruf'tt, 1838. Impregnation with chloride of zinc by sub- mitting the wood endwise to a jirrssure of ]•")() lbs. per sipiare iucli. Solution 1 lb. of the chloride to 10 gallons of water. Jttnirhcri. Impregnation by submitting the wood endwise to a jtressure of about ir> lbs. per sijuare inch. Solution 1 lb. of sulphate of copper to 1'2\ gallons of water. Jiethel. Impregnation by submitting the wood endwise to a pressure of 150 to 200 lbs. jier B(piare inch, with oil of creosote mixed witli bituminous mattiT. Louis S. liohhins, IHi',."). Atjueous vapor dissipated by the wood Ixiiig heated in a chaiiilMT, the albumen solidifiod, then Kubinitti'd to the vajxtr of coal tar, resin, or bituininons oils, which, being at a temperature not less than 325 , readily takea th" i>lace of tho vajKJr exjjelled by a temi)erature of 212'. Fluids will pass with the grain of wood with great fac^ility, but will not enter it except to a very limited extent when applied externally. WOOD, TIMBER, ETC. 145 Absorption of Preserving Solution by different Woods for a Period of Seven Days. Average Pounds per Cubic Foot. Black Oak 3 6 Chestnut. ...... .3. Hemlock.. Ked Oak. .2.6 .3.9 Rock Oak 3.9 White Oak 3.1 Proportion of Water in various Woods. Alder ( Beinla alwis) 41.6 Ash {Frojeinus excelsior). . . .28.7 Birch (BeMa alba) 30.8 Elm ( Ulmus campestris) .. .4-1.5 Horse-chestnut {^^scuius hippncasi) .... 38.2 Larch :Pinus lari.i) 48.6 Mountain Ash {Sorbusaucu- paria) 2^.3 Oak ( (^uercus roburi 34. 7 Pine {Pinus Sylvestns i.). .39.7 Red Beech ( Fagiis sylvaiica). 39. 7 Red Pine (Pinus picea durj. 45.2 Sycamore {Acer pseudo plat- anus ) 27. White Oak {Quercus aftff). .36 2 White Pine (Pinus abies dur) -M.l White FoY)]a.v[Populus alba).5i).6 Willow { Salix aiprea) 26. Ash.. Beech Cedar .1. .86 .66 Comparative EesUience of Timber. Chestnut . .73 I Larch ... .84 Elm 54 Oak 63 Fir 4 Pitch Pine .57 Spruce ... .64 Teak 59 Yel. Pine. .64 Weight and Strength of Oak and Yellow Pine. White O4S, Va. Yellow Pine, Va. Live Oak. Age. Round. Square. Round. Square. Green 1 Year 64.7 53.6 46. 67.7 53 5 49.9 47.8 39.8 34.3 39.2 34.2 33.5 78.7 2 Years 66.7 In England, timber sawed into boards is classed as follows: 6| to 7 ins. in width, Battens; 81 to 10 ins., Deals; and 11 to 12 ins., Planks. In a perfectly dry atmosphere the durability of woods is almost unlimited. Rafters of roofs are known to have existe.i 1,000 years, and piles submerged in fresh water have been found per- fectly sound 800 years from the period of their being driven. DistUUltion,. — From a single cord of pitch pine distilled by chemical apparatus, the following substances and in the quanti- ties stated have been obtained : Charcoal 50 bushels. Illum'ng Gas .ab't 1000 cu. ft. Illum'ng Oil and Tar. 50 galls. Pitch or Resin \\ barrels. 7 Pyroligenous Acid. .100 galls. Sp'ts of Turpentine 20 " Tar 1 barrel. Wood Spirit 5 gallons. 146 WOOD, TIMBER, ETC. Decrease in Dimensions of Tiniber by Seasoning. Woods. Ins. Ins. Cedar, Canada 14 to 13] Elm 11 to 1U5 Oak, English 12 to llf Pitch Pine, North 10 X 10 to O^ X 9| Pitch Pine, South 18^ to lb] Spruce «! to 8^ "White Pine, American 12 to 11^ Yellow Pine, North 18 to 17| The weight of a beam of English oak, when wet, was reduced by seasoning from 972.25 to 030.5 pounds. REVOLVING DISK. To compute the Power. Etjle. — Multiply one half-the weight of the disk by the height due to the velocity of its circumference in feet per second. Example.— A grindstone 3} feet in diameter, weighing 2,000 lbs., is required to make 362| rcsvolutions per minute ; what power must be communicated to it? Circum. of 3 1 = 10.6 feet, which X 3(52. 25 -f- GO = 04 feet per second. Then 2,000-^ 2 X r.4 = 64,000 lbs. raised 1 foot. Note.— If the revolving disk is not an entire or solid wheel, being a ring orannulus, it must fir.st be computed as if an entire disk, and then the portion wanting must be computed and de- ducted. Power concentrated in Moving Bodies. Simple power is force multiplied by its velocity Power con- centrated in a moving body is the weight of the b'ody multiplied by the square of its velocity; and the product divided by the accclleratrix, or the powcir concentratP«'« rr-A-H inch per foot. " Girders, beams, etc =:^ l-H in !"> inches. " Large cylinders, the contraction of ) , ,- , . diameter ut t..i.. \ = 1-16 per foot. " bottom .. :^M2 per foot. " " ccmtraction in length — 1-8 in 16 inches. Brass, thin ^ j.H j„ ., i,„.i,os. Brass, thick — 1-S in 10 in.-.hes. ^""" • — 5-16 in 11 foot. L'''"l 5-1 6 in 11 foot. ^'"I»I"r 3-16 in a foot. l^»»'""tli -:^ 5-32 in a foot. WHEEL GEARING. 147 WHEEL G-EARING-. The pitch line of a wheel, is the circle upon which the pitch is measured, and it is the circumference by which the diameter, or the velocity of the wheel, is measured. The pitch, is the arc of the circle of the pitch line, and is de- termined by the number of the teeth in the wheel. The true pitch i^chordial;, or that by which the dimensions of the tooth of a wheel are alone determined, is a straight line drawn from the centres of two contiguous teeth upon the pitch line. The line of centres, is the line between the centres of two wheels. The radius of a wheel, is the semi-diameter running to the periphery of a tooth. The pitch radivis, is the semi-diameter running to the pitch line. The length of a tooth, is the distance from its base to its ex- tremity. The breadth of a tooth, is the length of the face of wheel. The teeth of wheels should be as small and numerous as is consistent with strength. When a pinion is driven by a wheel, the number of teeth in the pinion should not be less than eight. When a wheel is driven by a pinion, the number of teeth in the pinion should not be less than ten. The number of teeth in a wheel shotild always be prime to the number of the pinion; that is, the number of teeth in the wheel should not be divisible by the number of teeth in the pinion without a remainder. This is in order to prevent the same teeth coming together so often as to cause an irregular wear of their faces. An odd tooth introduced into a wheel is termed a hunt- ing tooth or cog. To compute the Pitch of a Wheel. KuLE. — Divide circumference at the pitch-line by the number of teeth. Example. — A wheel 40 ins. in diameter requires 75 teeth ; what is its pitch ? 3.1416X40 ,^„, . ^g = 1.6755 ins. To compute the Chordial Pitch. KuLE.— Divide 180° by the number of teeth, ascertain the sine of the quotient, and multiply it by the diameter of the wheel. Example. — The number of teeth is 75, and the diameter 40 inches; what is the true pitch ? 180 ^ 2° 24' and sin. of T 24' = .04188, which X 40 = 1.6752 ins. 75 148 WHEEL GEARING. To compute the Diameter of a "Wheel. RuiiE. — Multiply the number of teeth by the pitch, and divide the ijroduct by 3.1416. Example. — The number of teeth in a wheel is 75, and the pitch 1.075 ins. ; what is the diameter of it? 11X1:615^40 ins. 3.1416 To compute the Number of Teeth in a Wheel. liuLE. — Divide the circumference by the pitch. To compute the Diameter when the True Pitch is given. Rule. — Multiply the number of teeth in the wheel by the true pitch, and again by .3184. Example. — Take the elements of the preceding case. 75 X 1.6752 X .3184 = 40 ins. To compute the Number of Teeth in a Pinion or Follower to have a given Velocity. Rule. — Multiply the velocity of the driver by its number of teeth, and divide the product by the velocity of the driven. Example. — The velocity of a driver is IG revolutions, the number of its teeth 54, and the velocity of the pinion is 48; what is the number of its teeth ? liX^i=. 18 teeth. 48 2. A wheel having 75 teeth is making IG revolutions per minute; what is the number of teeth reijuircd in the pinion to make 24 revolutions iu the same time ? 10 X 75 24 = 50 t«eth. To compute the Proportional Radius of a Wheel or Pinion. Rti.K. Miilti]ily the length of tlie line of erntris by the num- Ikt dT ti'i'tli in tlie wheel for the wheel, and ill tlie pinion for the j>iiiiiin, and divide by the number of tooth m both the wheel ond piiiiuu. WHEEL GEARING. 149 To compute the Diameter of a Pinion, when the Diameter of the Wheel and. Number of Teeth in the "Wheel and Pinion are given. KuLE. —Multiply the diameter of the wheel by the number of teeth in the pinion, and divide the product by the number of teeth in the wheel. Example. — The diameter of a wheel is 25 inche-s, the number of its teeth 210, and the niimber of teeth in the pinion 30; what is the diameter of the pinion? 25X30 210 ; 3. 57 ins. To compute the Circumference of a Wheel. KuLE. — Multiply the number of teeth by their pitch. To compute the Revolutions of a Wheel or Pinion. KuLZ. — Multiply the diameter or circumference of the wheel or the number of its teeth, as the case may be, by the number of its revolutions, and divide the product by the diameter, circum- ference, or number of teeth in the pinion. Example. — A pinion 10 inches in diameter is driven by a wheel 2 feet in diameter, making 46 revolutions per minute; what is the number of revolutions of the pinion ? ^ ^ ^^^^ ^^ = 110.4 revolutions. To compute the Velocity of a Pinion. KuLE. — Divide the diameter, circumference, or number of teeth in the driver, as the case may be, by the diameter, etc., of the pinion. When there is a Series or Train of Wheels and Pinions. Rule. — Divide the continued product of the diameter, circum- ference, or number of teeth in the wheels by the continued pro- duct of the diameter, etc., of the pinions. Example. — If a wheel of 32 teeth drive a pinion of 10, upon the axis of which there is one of 30 teeth, driving a pinion of 8, what are the revolutions of the last? 32 30 9G0 ,„ , ,. ro-^-8^8o=^2"'^°^^*^°^'- Ex. 2. — The diameters of a train of wheels are 6, 9, 9, 10, and 12 inches; of the pinions, 6, G, 6, 6, and 6 inches; and the num- 150 WHEEL GEARING. ber of revolutions of tlie driving shaft or prime mover is 10; what are the revolutions of the last pinion? GX9X9XlO Xi2XU)^5^^.- .evolutions. GX6X6X6X6 777b To compute the Proportion that the Velocities of the Wheels in a Train should bear to one another. Rule.— Subtract the less velocity from the greater, and divide the remainder by one less than the number of wheels in the train ; the quotient is the number, rising in arithmetical pro- gression from the less to the greater velocity. Example.— What should be the velocities of 3 wheels to pro- duce 18 revolutions, the driver making 3 ? 18 — 3=:::15__.y5__ number to be added to velocity of the driver =^7.5 4-3 = 10.5, and 10.5 + 7.5 = 18 revolutions. Hence 3, 10.5, and 18 are the velocities of the three wheels. General Illustrations. 1. A wheel 96 inches in dianicter, having 42 revolutions per minute, is to drive a shaft 75 revolutions per minute; what should be the diameter of the pinion V ^Xi^ = 53.7Gins. 75 2. If a pinion is to make 20 revolutions per minute, reqiiired the diameter of another to make 58 revolutions in the same time. 58 -^20 = 2.9 = the ratio of their diameters. Hence, if one to make 20 revolutions is given a diameter of 30 inches, the other will be 30 -^ 2.9 = 10. 345 ins. 3. Re(iuired tlie diameter of a pinion to make 12^, revolutions in the same time as one of 32 ins. diameter making 20. 32 X 2G _ p^p^ r,p. ing 12.5 4. A shaft, having 22 revolutions per minute, is to drive an- other shaft at tlio rate of 15, the distance bctw.'on the two shafts up(m tlie line of ccntriis is 45 inches; what should be the diame- ter of the wheels? Then, Ist, 22-1-15 : 22: : 45 : 20.75 = inches in the radius of the pinion. 2d. 22 f- 15 : 15 : : 4'. : 18.24 - inches in the radius of the spur. 5. A driving shaft, having 10 revolutions ]ter minute, is to drive a shaft 81 revolutions i)er minute, the motion to be com- mnnic;ited by two geand whe.ls and two jjulleys, with an int('r- niediate sliaft; th<^ driving wheel is to contain 51 teeth, and the driving i)iilley upon the driven shaft is to be 2'> inches in diam- eter; n-.iuired the number of teeth in the driven wheel, and the diameter of the driven pulley. WHEEL GEARING. 151 Let the driven wheel have a velocity of y Ui x 81 == 36, a mean proportional between the extreme velocities 16 and 81. Then, 1st. 36 : 16 : : 54 : 21 = teeth in the driven wheel. 2d. 81 : 36 : : 25 : 11. 11 = inches diameter of the driven pulley. 6. If, as in the i^receding case, the whole number of revolu- tions of the driving shaft, the number of teeth in its wheel, and the diameters of the pulleys are given, what are the revolutions of the shafts ? Then, 1st. 18 : 16 : : 54 : 48 = revolutions of the intermediate shaft. 2d. 15 : 48 : : 25 : 80 =; revolutions of the driven shaft. To compute the Diameter of a Wheel for a given , Pitch and Number of Teeth. KuiiE. — Miiltiply the diameter in the following table for the number of teeth by the pitch, and the product will give the di- ameter at the pitch circle. Example. — What is the diameter of a wheel to contain 48 teeth of 2.5 ins. J) itch? 15.29X2.5 = 38.225 ins. To compute the Pitch of a Wheel for a given Di- ameter and Number of Teeth. Rule. —Divide the diameter of the wheel by the diameter in the table for the number of teeth, and the quotient will give the pitch. Example. — Wha.t is the pitch of a wheel when the diameter of it is 50 94 inches, and the number of its teeth 80 ? 50 94 - . = 2 ms. 25.47 To compute the Stress that may be borne by a Tooth. liULE. — Multiply the value of the material of the tooth to resist a transverse strain, as estimated for this character of stress, by the breadth and square of its depth, and divide the product by the extreme length of it in the decimal of a foot. To compute the Number of Teeth of a Wheel for a given Diameter a''d Pitch. RtTLE. — Divide the diameter by the pitch, and o posite to the quotient in the following table is given the number of teeth. 152 WnEEL GEARING. Pitch of Wheels. A Table "W'Herebt to Compute the Diameter op a Wheeij fob a GIVEN Pitch, or the Pitch for a gxaen Diameter. From 8 to 192 teeth. No. of Diame- No. of Diame- No. of Diame- No. of Diame- No. of Diame- Teeth ter. Teeth. 45 ter. Teetli. ter. Teeth. ter. Teeth . 156 ter. 8 2.61 14.33 82 26.11 119 37.88 49.66 9 2 93 46 14.65 83 26.43 120 38.2 157 49.98 < 3.24 47 14.97 84 26.74 121 38.52 158 50.3 3.55 48 15.29 85 27.06 122 38.84 159 50.61 12 3.86 49 15.61 86 27.38 123 39.16 160 50.93 13 4.18 50 15.93 87 27.7 124 39.47 161 51.25 U 4.49 51 16.24 88 28.02 125 39.79 162 51.57 15 4.81 52 16.56 89 28.33 126 40.11 163 51.89 16 5.12 53 16.88 90 28.05 127 40.43 164 52.21 17 5.44 54 17.2 91 28.97 128 40.75 165 52.52 18 5.76 55 17 52 92 29.29 129 41.07 166 52.84 19 6.07 56 17.8 93 29.01 130 41.38 167 53.16 20 6.39 57 18.15 94 29.93 131 41.7 168 53.48 21 6.71 58 18.47 95 30.24 132 42.02 169 53.8 22 7.03 59 18.79 90 30.56 133 42.34 170 54.12 23 7.31 60 19.11 97 30 88 134 42,66 171 54.43 24 7.66 61 19.42 98 31.2 135 42.98 172 54.75 25 7.98 62 19.74 99 31.52 136 43.29 173 55.07 26 K3 63 20.06 100 31.84 137 43.61 174 55.39 27 8 61 64 20.38 101 32.15 138 4.3.93 175 55.71 28 8.93 05 20.7 102 32.47 139 44.25 176 56.02 29 9.25 66 21.02 103 32.79 140 44.57 177 56.34 30 9.57 67 21.33 104 33.11 141 44.88 178 56.66 31 9.88 08 21.05 105 33.43 142 4.5.2 179 56.98 32 10.2 ! 69 21.97 106 33.74 143 45.52 180 57.23 33 10.52 70 22.29 107 34.00 144 45.84 181 57.62 34 10.84 71 22.61 108 34.38 145 46.16 182 57.93 35 11.16 72 22.92 1(9 34.7 146 46.48 183 58.25 36 11.47 73 23.24 110 35.02 147 46.79 184 58.57 37 11.79 74 23.56 111 35.34 148 47.11 185 .58.89 3H 12.11 75 23.88 112 35.65 149 47.43 186 59.21 39 12.43 76 24.2 113 35 97 150 47.75 187 59.53 ■10 12.71 77 24.52 114 36.29 151 48.07 1 188 59.84 •11 1.3.(16 78 24.83 115 36.61 1.52 48 39 189 00.16 ■12 13.38 79 25.15 110 36.93 1.53 48.7 190 60.48 43 l.i 7 HO 2 "..47 117 37.25 154 49.02 191 60.81 41 14.02 i 81 2.5.79 118 37.56 155 49.34 ! 192 61.13 WHEEL GEARING. 153 Teeth of Wlieels, EpiCTCLOIDAIi. In order tliat the teeth of the wheels and pinions should work evenly and without unnecessary rubbing friction, the face (from pitch line to top) of the outline should be determined by an epicycloidal curve, and the flank (from pitch line to base) by an hypocj'cloidal. When the generating circle is equal to half the diameter of the pitch circle, the hypocycloid described by it is a straight diamet- rical line, and, consequently, the outline of a flank is a right line and radial to the centre of the wheel. If a like generating circle is used to describe face of a tooth of other wheel or i^inion respectively, the wheel and pinion will operate evenly. Im'OLUTE. Teeth of two wheels will work trulj' together when surfaces of their face is an involute ; and that tv.o such wheels should work truly, the circles from which the involute lines for each wheel are generated must be concemr-ic with the wheels, with diameters in the same ratio as those of th& wheels. Curves of" Teeth.— In the pattern shop, the curves of epi- cycloidal or involute teeth are defined by rolling a template of the generating circle on a template corresponding to the pitch line. A scriber on the periphery of the template being used to define the ciarve. Least number of teeth that can be employed in j^inions having teeth of following classes are : involute, 25 ; epicycloidal, 12 ; staves or pins, 6. Construction of Gearing. Kthe dimensions of two wheels are determined, as well as the size of the teeth and spaces, the wheel is drawn as is .shown in figure. The starting-point for the division of the wheels is Where the two pitch -circles )••, ,-' / x—^ meet in A. It , . ^' is advisable to \^ determine the exact diameters of the wheels by calculation, if the difference between them is remarkable; for any division upon two circles of unequal size, t 154 WHEKL GEARING. by meaBS of a divider, is incorrect, because the latter measures the chord instead of the arc. From the point A we construct the epicycloid C, by rolling the circle A upon B, as its base line. That short piece of the epicycloid, from the pitch-line to the face of the tooth, is the curvature for that part of the tooth and the wheel B. This curvature obtained for one side of the tooth, serves for both sides of it, and also for all the teeth in the wheel. The lower part of the tooth, or that inside the pitch-line, is im- material to the working of the wheel; this may be a straight line, as shown by the dotted lines which are in the direction of the diameters, or may be a curved line, as is seen in the wheel A. This line must be so formed as not to touch the upper or curved part of the tooth. T he root of the tooth, or that part of it which is connected with the rim of the wheel, is the weakest part of the tooth, and may be strengthened by filling the angles at the corners. The curvature for the teeth in the wheel A is found in a similar manner to that for B. The pitch-circle A serves now as a base-line, and the circle B is rollctl upon it, to obtain the circle I). This line forms the curvature for the teeth of A, and serves for all tlie teeth in A— also for both sides of the teeth. In most practical cases the curvature of the teeth is described as a part of a circle, drawn from the centre of the next tooth, or fi"om a pt)int more or less above or bt'low that centre, or the radius greater or les-s in length than the pitch of the wheel. Such circles are never correct curves, and no rule can be estab- lished by which their size ami centre meets the form of the epi- cycloid. Bevel Wheels, lii If the linos C A and B C represent the prolonged axes, which are to revolve withdifferentorsim- ilar velocities, the position and sizes of the wheels for driving these axes are determined by the distance of the wheels from the point C. The di- WHEEL GEARING. 155 ameters of the wheels are as the angles a and (5, and inversely as the number of revolutions. These angles are therefore to be de- termined before the wheels can be drawn. By measuring the distances from C to the line E, or from C to F, the sizes of the wheels are determined. These lines, E F and D F, are the diam- eters for the pitch-lines ; from them the form of the tooth is de- scribed on the bevelled face of the wheel. If the form of the tooth is described on the largest circle of the wheel, all the lines from this face run to the point C, so that when the wheel revolves around its axis, all the lines, from the teeth concentrate in the point C, and form a perfect cone. Curvature, thickness, length, and spaces are here calculated as on face wheels; the thickness is measured in the middle of the width of the wheel. Worm-Screw. If a single screw, A, works in a tooth- ed wheel, each rev- olution of the screw vill turn the wheel one cog; if the screw is formed of more than one thread, a corresponding num- ber of teeth will be moved by each rev- olution. With the increase of the num- ber of threads, the side motion of the wheel and screw is accelerated; and when the threads and number of teeth are equal, an angle of 45° is required for teeth and thread, provided their diameters also are equal. This motion causes a great deal of friction, and it is only resorted to where no other means can be employed to produce the re- quired motion. In small machinery, the worm is frequently made use of to produce a uniform, uninterrvipted motion; the screw in such cases is made of hardened steel, and the teeth of the wheel are cut by the screw which is to work in the wheel. If the form of the teeth in the wheel is not curved, and its face is concave so as to fit the thread in all points, the screw will 156 WHEEL GEARING. touch the teeth but in one point, and cause them to he liable to breakage. Proportions of Teeth, of Wheels. Tooth.- In computing the diiiaensions of a tooth, it is to be considered as a beam lixed at one end. the weight suspended from the othei", or face of the beam ; and it is essential to consid- er the element of velocity, as its stress in operation, at high velo- city with irregular action, is increased thereby. The dimensions of a tooth shoiald be much greater than is necessary to resist the direct stress upon it, as but one tooth is proportioned to bear the whole stress upon the wheel, although two or more are actually in contact at all times; but this require- ment is in conse(^uence of the great wear to which a tooth is sub- jected, the shocks it is liable to from lost motion, when so worn as to reduce its depth and uniformity of bearing, and the risk of the breaking of a tooth from a defect. A tooth running at a low velocity may be materially reduced in its dimensions compared with one running at a high velocity and witli a like stress. The result of operations with toothed wheels, for a long period of time, has determined that a tooth with a pitch of 'S inches and a breadth 7.5 inches will transmit, at a velocity of G.OG feet per second, the power of 5'J. 1 G horses. To compute the Depth of a Cast Iron Tooth. 1. When the Stress is given. Rule. — Extract the square root of the stress, and multiply it by .02. Example. — The stress to be borne b'y a tooth is 4,886 lbs, ; what should be its depth ? v/488GX.02 = l.lins. 2. Whek the Hokse-Power is gi\'en. IlyTJ5. — Extract the square root of tin; quotient of the horso*- power dividi-d by the velocity in feet jier second, and multiply it by .4(iG. Example. — The horse-power to bo transmitted by a tooth is no, and llie velocity of it at its pitch-line is ('>.(\t', feet i>er second: what sli(jidd bo the depth of the tooth V \ /5?-.X.4GG:.. 1.398 ins. / G 111) To compute the Horse-Power of a Tooth. Rule. -Multiply tlie pr.'ssure at the jtitcli-line, by its velocity in feet per minute, and divide tho product by 33,000. WHEEL GEARING. 157 CALCULATING fsPEED. When Time is not taken into Account. Rule. — Divide the greater diameter, or number of teeth, by the lesser diameter or number of teeth, and the quotient is the num- ber of revolutions the lesser will make, for one of the greater. Example. — How many revolutions will a pinion of 20 teeth make, for 1 of a wheel with 125 ? 125-^ 20 = 6.25 or 6^ revolutions. To find the Number of Revolutions of the last, to one of the first, in a Train of Wheels and Pinions. Rule. — Divide the product of all the teeth in the driving by the product of all the teeth in the driven; and the quotient equals the ratio of velocity required. Example 1. — Reqiiired the ratio of velocity of the last, to 1 of the first, in the following train of wheels and pinions, viz. : pin- ions driving — the first of which contains 10 teeth, the second 15, and third 18. "Wheels driven, first, 15 teeth, second, 25, and third, 32. — — — — = .223 of a revolution the wheel will make to one of 15 X 25 X 32 the pinion. Example 2. — Awheel of 42 teeth giving motion to one of 12, on which shaft is a pulley of 21 inches diameter driving one of 6; required the number of revolutions of the last j)ulley to one of the first wheel. 42 X "^1 ^ ' := 12.25 or 12i- revolutions. 12 X 6 * Note. — "Where increase or decrease of velocity is required to be commiinicated by wheel-work, it has been demonstrated that the number of teeth on each pinion should not be less than 1 to 6 of its wheel, unless there be some other important reason for a higher ratio. When Time must be regarded. EuLE. — Multiply the diameter or number of teeth in the driver, by its velocity in any given time, and divide the product by the required velocity of the driven; the quotient equals the nuti;bor of teeth or diameter of the driven, to produce the velocity re- quired. Example 1. — If a wheel containing 84 teeth makes 20 revolu- tions per minute, how many must another contain, to work in contact, and make 60 revolutions in the same time? 84X20 4- 60 = 28 teeth. Example 2. —From a shaft making 45 revolutions per minute, and with a pinion 'J inches diameter at the pitch line, I wish to 15S WHEEL GEARING. transmit motion at 15 revolutions per minute; wliat, at the pitct/ line, must be the diameter of the wheel ? 45 X 9 -T- 15 = 27 inches. Examples. — Required the diameter of a pullej' to make 16 revolutions in the same time as one of 24 inches making 36. 24 X 36 -^ 16 = 51 inches. The Distance heiween Ike Centres ami Vdociiies of Two Wheels being given, to find their Proper Diameters. S-ULE. — Divide the greatest velocity by the least; the quotient is the ratio of diameter the wheels must bear to each other. Hence, divide the distance between the centres by the ratio -j- 1; the quotient equals the radius of the smaller wheel; and suId- tract the radius thus obtained from the distance between the centres; the remainder equals the radius of the other. Example. — The distance of two shafts from centre to centre is 50 inches, and the velocity of the one 25 revolutions per minute, the other is to make 80 in the same time; the proper diameters of the wheels at the pitch lines are required. 80-^25 = 3.2, ratio of velocity, and 50-;- 3.2 + 1 = 11.9 the radius oi" the smaller wheel; then 50 — 11.0 i= 38.1, radius of larger; their diameters are 11.9 X 2 = 23.8 and 38.1 X 2 = 76.2 inches. To obtain or diminish an accumulated velocity by means of wheels and pinions, or wheels, pinions, and pulleys, it is neces- sary that a proportional ratio of velocity should exist, and which is thus attained; multiply the given and reijuircd velocities to- gether; and the s<{uaro root of the product is the mean or pro- portionate velocity. Example. — Let the given velocity of a wheel containing 54 teeth equal 16 revolutions per minute, and the given diameter of an intermediate piiUey equal 25 inches, to obtain a velocity of 81 revolutions in a machine; required the number of teeth in the intermediate wheel and diameter of the last pulley. v/81 X 16 = 36 mean velocity; 54 X 16-i- 36 = 24 teeth, and 25 X 36-1-81 = 11.1 inches, diameter of pulley. Tablo of tho Weight of a Square Foot of Sheet Iron in Pounds Avoirdupois. No. 1 is ,'',., of an inch; No. 4, {; No. 11, J, Ac. No. oil win-gaugo, 1 2 3 4 5 6 7 8 9 10 11 Pounds avoir., 12.5 12 11 10 9 8 7.5 7 6 5.68 5 No. on wiro-gftugo, 12 13 It IT) 16 17 18 19 20 21 22 ToundH avoir., 4.62 4.31 1 3.',t5 3 2.5 2.18 1.93 1.62 1.5 1.3'? SCREW CUTTING. 159 SCREW CUTTING-. In a lathe iiroperly adapted, screws to any degree of pitch, or number of threads in a given length, may be cut by means of a leading screw of any given pitch, accompanied with change wheels and pinions; coarse pitches being effected generally by means of one wheel and one jnnion with a carrier, or intermediate wheel, which cause no variation or change of motion to take place. Hence the following ^^ KuiiE. — Divide the number of threads in a given length of the screw which is to be cut, by the number of threads in the same length of the leading screw attached to the lathe; and the quo- tient is the ratio that the wheel on the end of the screw must bear to that on the end of the lathe spindle. Example. — Let it be required to cut a screw with .5 threads in an inch, the leading screw being of X inch pitch, or containing 2 threads in an inch; what must be the ratio of wheels api^lied? 5-^2 = 2.5, the ratio they must bear to each other. Then suppose a pinion of 40 teeth be fixed upon for the spindle: 40 X 2.5 = 100 teeth for the wheel on the end of the screw. But screws of a greater degree of fineness than about 8 threads in an inch are more conveniently cut by an additional wheel and pinion, because of the proper degree of velocity being more efi"ec- tively attained; and these, on account of revolving upon a stud, are commonly designated the stud-wheels, or stud-wheel and pin- ion; but the mode of calculation and ratio of screw are the same as in the preceding rule. Hence, all that is further necessary is to fix upon any 3 wheels at pleasure, as those for the spindle and stud-wheels; then multiply the number of teeth in the spindle- wheel by the ratio of the screw, and by the number of teeth in that wheel or pinion which is in contact with the wheel on the end of the screw; divide the product by the stud-wheel in con- tact with the spindle-wheel; and the quotient is the number of teeth required in the wheel on the end of the leading screw. ExAMPiiE. — Suppose a screw is required to be cut containing 23 threads in an inch, and the leading screw, as before, havmg two threads in an inch, and that a wheel of 60 teeth is fixed upon for the end of the spindle, 2 ) for the pinion in contact with the screw-wheel, and lUO for that in contact with the wheel on the end of the spindle; required the number of teeth in the wheel for the end of the leading screw. 25 ^ 2 = 12. 5, and ^^ ^ ^^^^ ^ ^^^ = 150 teeth. Or suppose the sjiindle and screw-wheels to be those fixed upon, also any one of the stud-wheels, to find the niimber of teeth in the other. GO X 12.5 „^^ ., 60X12.5X20 ,^^ ^ ^, 150 X 100 ^ ^^ *'''^' "' i50~~ =^ ''^ ''''^- 160 WATER-WHEELS. WATER- WHEELS. The properties of water, as a motive power, are gravity and im- pulsive force, e.ach being renlereil peculiarly available for the production of uniform circular motion through the medium of the water-wheel. Water-wheels are necessarily and designedly of various modi- fications, so as to obtain the greatest amount of mechanical effect from a known quantity of water llowing at a certain A'clocity, or from a ^iven height, and generallj' ranked, by estimation of effect, into first, second, and third class wheels. 1st class includes overshot-wheels, pitchback-wheels, and tur- bines. 2d class consists of breast-wheels, or those which receive the water below the level of tlie axis. And 3d class is composed of undershot-wheels, tub-wheels, and llutter-wheels. The most modern and best-conducted experiments on each description, as known to the yjublic at i)resent, are those by Poncelot of America, and of Morin in Fnmce, the results of which are as follows: Ovcrsliot-wheels, &c. ; ratio of power to effect, varies from . 60 to .80 Lreast-wheels, " " " .45 to. 50 Undershot-wheels, etc. " " " .27 to. 30 The greatest effect is obtained by an overshot-M-hcel when the diameter of the wheel is so proportioned to the height of the fall, that the water shall flow upon the wlieel at a point about ^21 degrees distant from the top of the wheel. If the portion of the total descent passed through by the water be given, then the velocity of the circumference should bo one- half of that, due to this height. Therefore, multiply the portion of fall, in feet, by 04.38, and the S(jnare root of the pi'oduct equals the water's vdocitj', in feet, per second. Also, If the area of cross-section of tlie overflow be multiplied by tho velocity at the end of the fall, the product equals the quantity, in cubic feet, per second. Experiments on Overshot- Wheels. 1. Whi'ii the depth of water in the reservoir is invariable, the diameter of tlie wheel should never exceed the (entire height of the fidl, less so much as is requisite to generate a i)roper velocity on eiiti'ring the bnclcets. 2. WIkto the deiith of water in the reservoir varies consider- ably and unavoidably, an advantage may be obtained by ajiply- ing a larger wheel, dc^pendcnt uj)on tiie extent of fluctuation, ainl ratio in time, that tlie water is at its highest or lowest levels (biriii;,' a given ]irolonged ])eri.)ower to eftect, and the quotient equals the mechanical effect of the wheel, expressed in horse-power. ( 1st class wheels, 47,190 Co-efficients ^ 2d class " 69,300 ( 3d class " 115,500 Or multiply the product of the quantity of water expended, in cubic feet, per minute, and the velocity of the wheel, in feet, in the same time, by the following decimal equivalents; the pro- duct will be the number of horse-power that the wheel is equal to in useful effect. ( l.st class wheels, .00132"; Decimal equivalents } 2d class " .000902 ( 3d class " .000541 Example. — Suppose a stream of water flowing on an overshot- wheel at the rate of 95 cubic feet per minute, and the velocity of the wheel's periphery etpials 6 feet per second, or 360 feet per minute; required the efiect of the wheel in horse-power. 360 X 95X62.5 iT\Q~) ^^ horse-power. Or, 360X95 X -001325 = 45.29 " Note. — When the fiiU of water does not exceed 4 feet, an under- shot-wheel ought to bo applied; from 4 to 10 feet, a breast-wheel; and from 10 feet upward, an overshot or pitchback wheel. To ascertain the Power of a Stream. KuLE. — Multiply the weight of the water, in jiounds, dis- charged in one minute by the height of the fall in feet ; divide by 33,000, and the quotient is the answer. Example. — What power is a stream of water equal to of the 152 WATER-WHEELSi following dimensions, viz.: 1 foot deep by 22 inches broad, velocity 350 feet per minute, and fall GO feet; and v/hat should be the size of the wheel applied to it ? 12 X 22 X 350 X 12^ 1728 X 02^ X 60 feet ^ 33000 = 72.9. Ans. Hei"ht of fall GO feet, from which deduct, for admission of water "^md clearance below, 15 inches, which gives 58.U feet for the diameter of the wheel. Clearance above 3 ) ^5 j^^j^gg^ " below 12 J The power of a stream, applied to an overshot-wheel, produces effect as 10 to 6.6. Then, as 10 : 6.6 : : 72.9 : 48 horse-power equal that of an over- shot-wheel of GO feet applied to this stream. When the fall exceeds 10 feet the overshot-wheel should be ap- plied. , T 1 1 i. The higher the wheel is in proportion to the whole descent, the greater will bo the eifect. The cfifect is as the quantity of water and its perpendicular height multiplied together. The weight of the arch of loaded buckets, in pounds, is found by multipryiug 4-9 of their number, X the number of cubic feet in each, and that product by 40. To ascertain the Power of an Undersliot-Wheel when the Stream is confined to the Wheel. Rule. —Ascertain the weight of the water discharged against the floats of the wheel in one minute by the ])receding rules, and divide it by 100,000; th(! quotient is the number of horse-power. Note.— The 100,000 is obtained thus: Tlie power of a stream, applied to an undershot-wheel, produces effect as 10 to 3.3; then 3.3 : 10 : : 33,000 : 1(;0,000. When tlie opening is above the centre of the floats, multi])ly weight of the water by tlie height, as in the rule for an overshot ■wheel. Example. —What is the power of an undershot- wheel, applied to a stream 2 by 80 inches, from a head of 25 feet ? /25 X 6 5 X 60 — 19.')0 U-ct velocity of water ])er minute, and 2 X 80 = 16') inches X 1950 X 12 X 1728 -^ 21(i(;.(; cubic fec^t X 62.6 = *135412 lbs. of water discharged in one minute; then 135412 -^ 100000 — 1.35 horse-power. To find the Power of a Breast-Wheel. Role.— Find thjMiffcctof an undershot-whed, the liead of water of which i8 the diflferenco of level between the surface and where it • Erinnl 160 X 12 -r- 1728 X 62.5 X I'J^O = momentum of water I nd itH velocity. WATER-WHEELS. 163 strikes the wheel (breast), and add to it the effect of that of an overshot-wheel, the height of the head of which is equal to the difference between where the water strikes the wheel, and the tail water; the sum is the effective power. Example. — What would be the power of a breast-wheel applied to a stream 2 X 80 inches, 14 feet from the surface, the rest of the fall being 1 1 feet ? ,/ 14 X 6.5 X 60 =r 1458.6 feet velocity of water per minute. And 2X80X 1458X12 -f- 1728=: 1620 cubic feet X 62.5 = 101250 lbs. of water discharged in one minute. Then 101250 -^ 100000 = 1.012 horse-power as an undershot. v/llX65X60 = 1290 feet velocity of water per minute. And 2 X 80 X 1290 X 12 -I- 1728 = 1433 cubic feet X 62.5 = 89562 lbs. of water discharged in one minute, which X 1 1 height of fell -i- 50000 = 19.703 horse-power, which, added to the above, 1=20.715. Ans. Note.— When the fall exceeds 10 feet, it may be divided into two, and two breast-wheels applied to it. When the fall is between 4 and 10 feet, a breast-wheel should be applied. The power of a water-wheel ought to be taken off" opposite to the point where the water is producing its greatest action upon the wheel. Bemarks on Reaction Water- Wlisels. Keaction water-wheels are a very numerous family, of which the well-known hydraulic motor, called Barker's mill, is the pa- rent ; those used in various parts of the United States have usually vertical axes of rotation, and curved buckets, or vanes, against which the impulsive force of the water (spouting from within the wheel by adjutages, of which the curved vanes form the sides) acts indirectly, or rather reacts, thus producing (in reference to the affluent water) a backward rotary motion, similar, in character and effect, to the forward rotary motion produced by direct im- pulse in the case of undershot-wheels. In the American Philosophical Transactions for 1793, it is stated that the principles of reaction wheels had been fully in- vestigated analytically in examining the merits of Rumsey's im- provements on Barker's mill; and the conclusion come to, after a train of reasoning based upon scientific principles, was, that "ac- tion and reaction are equal;" that the undershot-wheel is pro- pelled by the action; and Barker's mill by the reaction of the same agent, or momentum; therefore their mechanical effects must be equal. This conclusion no doubt tended to retard any effort at im- provement of wheels on that principle for a considerable length of time; for it is only, comimratively sjDeaking, quite recently that reaction water-wheels, of the form at present in use, have occupied a prominent position before the public. 1G4 WATER-WHEELS. In 1830, Calvin Wing, of the United States, took otit a patent for a reaction water-wheel with curved vanes or buckets, the vanes of which lapped over, or rather on to each other, in the ratio of li inches for each inch of the width of the adjutage, or shortest horizontal distiuice between any two adjacent vanes. In this wheel the water has free entrance to a circular space within, and, sjiouting out by the oi>oniugs between the curved vanes, impels the wheel around in a backward direction, by its reaction against the vanes, in issuing with velocity from within the wheel. But this species of wheel, so far, seems not to realize the amount of effect as anticipated; for, according to rec(>nt experi- ments, it appe rs that, with 788 cubic feet of water, at the rate of one foot per miniite, ai>plied on an overshot-wheel, will grind and dress one bushel of wheat per hoiar; where&s to do the same by means of the reaction wheel required 1,600. Some of later date, as the turbine of France, by M. Fourney- ron, and the recently patented water-mill, by Whitelaw and Stir- rat, Scotland, seem much improved hydraulic motors; for, ac- cording to the experiments of IVI. Morin, and others of high au- thority, they rank, in effect to jjower, equal to first-class wheels. The chief objection to the common overshot-wheel, is its great size anl formidable cost, to whicli might be added, the loss of power consequent on the friction of the gearing requisite for bringing up the sjieed of the prime mover to the velocity indis- pensaljlc to most ordinary mechanical operations. These objec- tions do not apply to this species of water-power, as the machine occupies but a very small s]iace in comparison witli a water-wheel of the same power; its speed is high, ixnd tiie expense of its con- struction greatly inferior to that of any other effectual mechanism we are at jjresent acquainted with for deriving a rotary motion from a head of water. The arms of the machine by Whitelaw and Stirrat are bent in the form of ai Archimedes spiral, so as to obviate tlie communica- tion of a centrifugal force to the water, which, il*th( arms were straiglit, it would necessarily ac(iuire to the diminution of tho useful effect. Any number of arms may be used, but two is the common number. The machine revolves horizontally, and tlio afHucnci- of tho water at tlio orifices of tho arms is regulated by means of valves of a p(!culiar description, governed by tho cen- trifugal force of tho machine, or, iu other words, by its velocity. Turbines. In liigh-prossuro turbims the reservoir (of tho wheel) is in- closed at top, and the water is a=> ' j per minute. s/ Height ft. X area orifice, ins. X 2.2 = Do. do. It may be observed, that the above rules rejjresent the actual quantities that will be delivered through a hole cut in the plate; if a short pipe be attached, the quantity will be increased, the greatest delivery with a straight pij^e being attained with a length equal to 4 diameters, and being 1-^ more than the delivery through the plain hole; the quantity gradually decreasing as the length of pipe is increased, till, with a length equal to GU diam- eters, the discharge again equals the discharge through the plain orifice. If a taper jiipe be attached, the delivery will *be still greater, being U times the delivery through 'the plain orifice; and it is probable, that if a pipe with curved decreasing taper were to be tried, the delivery through it would be equal to the theoretical discharge, which is about 1.65 the actual discharge through a plain hole. To FIND the Quantity of Water that will run through any Orifice, the Top of which is level -with the SSurkace of Water, as over a Sluice or Dam /Height ft. from water-surface to bot- | Area of water- l^n-in V torn of orifice or top of dam \ ^ jiassage, sq.ft. j" ^ -iio = cubic ft. discharged per minute. Two-thirds area of water-passage, sq. ins. X No. corresponding to height, as per table = cubic feet discharged per minute. To FIND the time IN WHICH A VeSSEL WILL EMPTY ITSELF through a given ORIFICE. y/ Height ft. surfac e above orifice X area water-surface, sq ins. Area orifice, sq. in. X 3.7 ~" = Time required, seconds. The above rules are founded on Bank's experiments. 16.S SPECIFIC GRAVITIES. TABLE OP SPECIFIC GRAVITIES. Liquids. Di'vide the Specific Gravity by 16, and the quotieut is the weight oi a cubic foot Specific in lbs. Gravity. Acid, acetic 1.0(32 " nitric 1.217 " sulphuric 1.841 " muriatic 1.200 Alcohol, pure 7i)2 " of commerce 835 Oil, essential, turpentine. .870 " olive 915 " whale 925 " linseed 9;J2 Proof spirit 925 Vinegar 1.080 Water, distilled 1.000 Ether, sulphuric 715 Honey 1.450 Human blood 1.054 Milk 1.032 W ater, sea 1. 020 Dead Sea 1.240 Wine 992 " port 997 " champagne 997 Elastic Fluids. Divide the Sppcific Gravity by 16, and the quoticut is the weight of a cubic foot Specific in lbs. Gravity 1 cuV)ic ft. of atmospheric air weighs 527.04 troy grains. Its assumed gravity of 1 is the unit of elastic fluids .1.000 Ammoniacal gas 597 Azote 97() Carbonic acid 1.524 Carbureted hydrogen 555 Chlorine 2.470 Chloro-carbonic 3.389 Hydrogen 070 Oxygen 1.1('4 Sulphureted hydrogen. . . .1.777 Steam, 212° 490 Nitrogen 972 Vapor of alcohol 1.613 " turpentine spts .5.013 water 023 Sinoke of bituminous coal. .102 " wood 900 Metals. Divide tlie Rpociflc Gravity by 16, and tlie quotient JH the weight ol a cubic foot Rpedflc lu IbH. Gravity. Antimony 0.712 Arsenic 5. 703 histuuth 9.823 IJrass, common 7.820 Brf>nze, gun-metal H.V'iO Copper, ca.st 8.788 " wire drawn. . . 8.878 Gold, pure, cast 19.258 " hammend 19.301 •• 'n carats finf* 17.4S0 " 20 carats line 15.7ii9 Iron, coHt 7.207 Divide the Specific Gravity by 16. and th(! (piotieDt is tlie weight of a cubic foot Specific lu lbs. Gravity. Iron bars 7.788 L.'ad, east 11.352 Mercury, 32^ 13.598 00'' 13,580 riatinum, rolled '22.009 haiiimored 20.337 Silver, i>nre. cast 10.474 " iiamuiered 1((.511 Steel, soft 7.833 " teinp'd and hard'd 7.818 Tin, Cornish 7.291 Zinc, cast (!.801 HYDRAULICS. 160 HYDRAULICS. The science of hydrodynamics embraces hydrostatics and hy- draulics, the former of which treats of the properties and equi- librium of liquids in a state of rest, and the latter of liquids in motion, as conducting water in pipes, raising liquids by pumps, &c. 1. The peculiar distinguishing properties of liquids or fliiids in general are, capability of flowing, and constant tendency to press outward in every direction. 2. Fluids are of two kinds, aeriform and liquid, or elastic and non-elastic; that is, bodies of which are easily compressed into a smaller bulk, and bodies which are scarcely susceptible of com- pression. Atmospheric air, steam, or vapor of water, and all other gaseous bodies, are of the first kind; and water, alcohol, mercury, &c., are of the second. Compression of Liquids, in Millionth Parts per Atmosphere. Mercury, 2.65] Alcohol, 21.60 /..i • • • 1 -u n Water, 46. 63 °^ *^^^^ ^^^g^^'^^ ^"^^• Ether, 61.58 J 3. The weight of water or other fluid is as the quantity, but the pressure exerted is as the vertical height. 4 Fluids press equally in all directions; hence, any vessel containing a fluid sustains a pressure equal to as many times the weight of the column of greatest height of that fluid, as the area of the vessel is to the sectional ai-ea of the column. 5. The hydraulic press is of this principle. A jet of water is thrown into a cavity by means of a force pump; the action and non-compressible property of the liqi;id repels a jiiston or ram, the force of which equals the product of the effective power or pressure exerted on the fluid in the pump, multiplied by the number of times the area of the base of the ram exceeds the sec- tional area of the pump. ExAMPLK. — Reqiaired therei^ulsive force of a six-inch ram, when a power of 50 lbs. is ai^plied to the end of the lever, which is as 12 to 1, and the diameter of the pump or plunger 7-8 of an inch. Area of ram = 28. 2744 , ^ • • — 47 ' Area of pump = .6013 ' and 50 X 12 X 47 = 28,230 lbs., or 12 tons, nearly. 6. The lateral pressure of a fluid on the sides of any vessel in which it is contained is equal to the product of the length multi- plied by half the stpiare of the depth, and by the weight of the fluid in cubic unity of dimensions. 8 170 HYDRAULICS. Example. — A cistern 12 feet square find 8 feet deep is filled with water; required the whole amoiint of lateral pressure. (Weight of a cubic foot of water, 62.5 lbs. ) 12 X 4 = 48 feat, the whole length of sides, ,8^ -„ ,, 48X32X62.5 ... and _- = 32 ; then — — = 48 tons net. 2 2uOj 7 Fluids alwaj's tend to a natural level, or curve similar to the earth's convexity, every point of which is equally distant from the centre of the earth, the apparent level, or level taken bj' any instrument for that purpose, being only a tangent to the earth's circumference; hence, in levelling for canals, Ac, the difference causi'd by the earth's curvature must be deducted from apparent level to obtain the true level. When the distance is ' Feet, Yards, Chains To find the Difiference between True and Apparent Level. r.f 00000287 ] equal the the square | j difference in of that I nnnnn^r^sT I inches when distance ] -OOOOOioSJ |- refraction is multiplied by | | not taken [.00125 J into account. If the distance is considerable, and refraction must be attended to, diminish the distance in respect to calculation by 1-12. Ex^vMPLE. What is the difference between true and apparent level at a distance of 18 chains, when refraction is taken into account ? 18 -5^1.5, and 18 — 1.5 = 16.5" X. 00125 = .3133 inch. 1a 8. When a body is partly or wholly immersed in a fluid, the vertical pressur(' of the fluid lends to raise the body with a force equal to the W(Mght of tlic fluid displaccil; hence, the weight of any displaccul (juaiitity of a fluid by a buoyant body equals the wtaght of that body. 9. The centre of i)rcssure, and also the centre of percussion in a fluid, is two-thirds tlie dei)th from the surface. 10. Th(! r<'sistanc(! by whi(!h a moving body is oj)posed in jiass- ing through a liquid is as the K(|uare of its velocity: hence, if a body be projiclhtd at a certain vcdocity by a known i>ow('r, to doubli' that velocity will reciuire four times the power; to triple it, nine times the power, &c. Of Liquids in Motion. Tlie flowing of water through pipes, or in natural channels, is lialili; to b(! materially attcctc'd by friction. Water flows smoothly and with least retardation wlieii the course is i)erfectly smooth and straight. ICvery little inr-quality which is present(^d to the liquid tends to retard its motion, and so likewise docs every bend or angle in its path. HYDRAULICS. 171 1. When water issues out of a circular aperture in a thin plate on the bottom or side of a reservoir, the issuing stream tends to converge to a point at the distance of about half its diameter out- side the orifice, and this contraction of the stream reduces the area of its section from 1 to .66G, according to Bossut ; to .631, according to Venturi ; and to .64, according to Eytelwein. But, from more accurate experiments, it is found that the quantity discharged is not sufficient to fill this section with the velocity due or corresponding to the height, and that the orifice must be diminished to .619, or nearly f. 1. When water issues through a short tube, the vein of the stream is less contracted than in the former case, in the propor- tion of 16 to 13 ; and if it issues through an aperture which is the frustum of a cone, whose greater base is the aperture, the height of the frustum, half the diameter of the aperture, and the area of the small end to the area of the large end as 10 to 16, there will be no contraction of the vein. Henc«, when the greatest possible supply of water is required, this form of orifice ought to be employed. Table, Showing the Quantity of Wateb dischaeged per Minute bt Ex- PEEIMENTS WITH OeITICES DIFFERING IN FoRM AND POSITION. Constant Weight Number of of the fluid above Form. Position. Diameter of the Orifice. Cubic Inches the centre of the discharged Orifice. per minute. FT. IN. LINES. 11 8 10 Circular. Horizontal. 6 lines. 2.311 (( n 12 " 9.281 (( ft 24 " 37.203 Rectangular. li 12 by 3. 2.933 Square. It 12 side. 11.817 (( it 21 " 47.361 9 Circular. Vertical. 6 lines. 2.018 (( (( 12 " 8.135 4 n a 6 " 1.353 (< a 12 " 5.436 5 7 (C a 12 " .628 Deductions from the Preceding Experiments. 1. That the quantities of water discharged in equal times by the same orifice, from the same head of water, are nearly as the areas of the orifices. 2. That the quantities of water discharged in equal times by the same orifices, under different heads, are nearly as the square roots of the corresponding heights of the water in the reservoir, above the surface of the orifices. 1Y2 HYDRAULICS. 3. That the quantities of water discharged during the same time by difierent apertures, under different heights of water in the reservoir, are to one another in the compound ratio of the areas of the aportiires, and of the square roots of the heights in the reservoir. 4. That, on account of the friction, small orifices discharge proportionally less lluid than those which are larger and of simi- lar figure, under the same altitude of fluid m the reservoir. 5. That, in consequence of a slight augmentation which the contraction of the fluid vein undergoes, in jjroportion as the height of the fluid in the reservoir increases, the expenditure ought to be a little diminished. 6. That circular apertures are most advantageous, as they have less rubbing surface under the same area. 7. That the discharge of a fluid through a cylindrical horizon- tal tube, the diameier and length of which are equal to one another, is the same as through a simple orifice. 8. That if the cylindrical horizontal tube be of greater length than the extent of the diameter, the discharge of water is much increased, and may be increased with advantage to four times the diameter of the orifice. Weight of Water at its Common Temperature. 1 cubic inch = .03(J17 lbs. 12 " inches = .434 " 1 " foot =G2.5 " 1 " " = 7.81 gallons. 1.6 " feet = 1 lb. 32 << '« =1 ton. 1 cylindrical inch = .02^42 lbs. 12 " inches = .341 " 1 " foot =49.1 «' 1 " " = 6.130 gallona 2.036 " feet = 1 cwt. 40.73 " " =1 ton. 12.5 gallons ^^ 1 cwt. 250 " =1 ton. On the Discharge of Water by Horizontal Conduit, or Conducting Pipes. 1. The less the diameter of the pipe, the less, proportionally, is the discliarge of fluid. 2. The greater the hmgth of conduit pipe, the greater tha diminution of discharge. 3. Tlie dischargrs made in etjual times, by horizontal pipes of diflfenint b'ngtlis, but of the samc! diameter, and undi-r tlio same altitude of watdies moving round a cu'iitral point, have a tendency to fly off in a straight lino: this tendency is called the centrifugal force: it is opposed to the centripetal force, or that power which maintains the bo ly in its curvilinear path. The centrifugal force of a body, moving witli different veloci- ties, in the same circle, is proportional to tho sijuaro of tho velocity, or to tlie ?(inar(i of tlie number of revolutions perform- ed in a given tinu;. I lius, the centrifugal force of a body luaking 40 revolutions i)er minute, is 4 timers as groat as the cc^itrifugal force of the samo body when making 20 revolutions per minute. To find the Centrifugal Force of any Body. Boles. — 1. Divide tlie velocity in feet, per second, liy 4.01, and the s(iuaro of tho (juotient by tlio diametor of the circle; the (piotitait is tlio (vntrifugal force wluiii the weight of tho body is 1. Hence, tho (piotient multiplied by the weight of the body, is tho centrifugal force. Example. lle(juir(nl tho centrifugal force of the rim of a fly- whool, 20 foot in diameter, moving with the velocity 32 1-G feet in u second. 32 1-0 — 4.01=8.02; 8.02--|-2a = 3.210 times tho woiglit of tlio rim. 2 Multiply tho scjuaro of tho number of revolutions in a minute by tho diameter of the circle in feet, and divide tho PLY-WHEEL. 179 product by the constant number 5370; the quotient is the centrif- ugal force when the weight of the body is 1. Hence, as in the 1st rule, the quotient multiplied by the weight of the body, is the centrifugal force. Example. — Required the centrifugal force of a stone, weighing 2 lbs., revolving in a circle i feet in diameter, at the rate of 120 revolutions in a minute. 120' X -4 = 57600 : and ^I^=9.8L 5870 Hence, 9.81 X 2 = 19.G2 centrifugal force. Dr. Brewster has summed up the whole doctrine of centrifugal forces in tlie following propositions : 1. The centrifugal forces of two unequal bodies, moving with the same velocity, and at the same distance from the central body, are to one another as the respective quantities of matter in the two bodies. 2. The centrifugal forces of two eqiial bodies, which perform their revolutions round the central body in the same time, but at different distances from it, are to one another as their respec- tive distances from the central body. 3. The centrifugal forces of two bodies which perform their revolutions in the same time, and whose quantities of matter are inversely as their distances from the centre, are equal to one another. 4. The centrifugal forces of two equal bodies, moving at equal distances from the central body, but with diflferent velocities, are to one another as the squares of their velocities. 5. The centrifugal forces of two unequal bodies, moving at equal distances from the centre, with different velocities, are to one another in the compound ratio of their quantities of matter, and the squares of their velocities. 6. The centrifugal forces of two equal bodies, moving with equal velocities at different distances from the centre, are in- versely as their distances from the centre. 7. The centrifugal forces of two unequal bodies, moving with equal velocities at different distances from the centre, are to one another as their quantities of matter multiplied by their respec- tive distances from (he centre. 8. The centrifugal forces of two unequal bodies, moving with unequal velocities at different distances from the central body, are in the comi^ound ratio of their quantities of matter, the squares of their velocities, and their distances from the centre. THE FLY-WHEEL. It is an object of great importance in machines to have means of accumulating power when the moving force is in excess, and of expending it when the moving force operates more feebly or the resistance increases. This equalization of motion is obtained ISO FLY-WHEEL. by what is called the fly-wheel, which is generally made in the form of a heavy wheel. The flj'-wheel being made to revolve about its axis, keeps np its force by its own inertia, and distrib- utes it in all parts of its revolution. Fly-wheels are capable of accumulating power to a great extent, and, when thus accumu- lated, they assist in bringing the crank past its entres, but much of their efficacy depends on the position assigned them in the machinery. If the tly is used as a regulator of force, it should be placed near the prime mover; but if, on the other hand, it be used as a magazine of power, it should be near the working point. No general rules can be given for its exact position. To find the Weight of the Rim or Ring of a Ply- Wheel proper for a Steam-Engine. Rule. — Multiply the constant number 13G8 by the number of horse-power that the engine is ecpial to ; divide the product by the diameter of the wheel in feet, multiplied by the number of revolutions per minute, imd the quotient is the weight of the ring in 100 pounds nearly. Example. — Required the weight of the rim of a fly-wheel proper for an engine of 30 horse-i)o\ver, the wheel to be H feet in diameter, and making 40 revolutions per minute. 1:3GSX30 4104) .. , . T4x4ur=-5G(r==^^-^"^- Note. — The fly-wheel of an engine for a flour-mill ought to bo of such a diameter that the velocity of the periphery of the wheel may exceed the velocity of the periphery of the stones, to pre- vent, as much as possible, any tendency to back lash, as it is termed. The necessary weight and diameter of the wheel being found, suppose a breadth of a rim. Then, To find the Thickness necessary to make the Weight in Cast Iron. Rule. — Divide the required weight in pounds by the area of th(^ ring in inches multiplied by .'2G1, and the quotient is the thickness of the ring in inches. ExA>fPLE. — ^V^lat thickness must a ring of a fly-wheel be to equal f>4. 1 cwt., when the outer diann'ter is 14 feet and the inner diameter 12 feet? r.4.1 cwt. ^WlOlbs. Diam. 14 feet — 108 in. and 12 ft = 144 in., and the area of the ring := 5881 sq. in. „. r,410 fi-UO , ,„ . T^«"' r,881 xT2iir^l53.50 = ^-^^^^- "^'^y* Note.— If the ring is to bo of a cylindrical form, its diameter may ha easily found bv the following ajjproximate FLY-WHEEL, ETC. 181 Rule. — Multiply the required weight in jioumls by 1.62; di- /ide the product by the diameter of the wheel in inches and the sqiiare root of the quotient will be the diameter of the cross- section of the ring in inches, nearly. Thus, y/ 6410 X iH2 = 7.7 inches. Note. — The centre of percussion in a fly-wheel, or wheels in general, is | distant from the centre of suspension, nearly. The centrifugal force is that power or tendency wlaich all revolv- ing bodies have to burst or Ay asunder in a direct line. And the centre of percussion in a revolving body is that point where the whole force or motion is collected, or that point which would strike any obstacle with the greatest effect. MELTING POINT OF SOLIDS. Cast Iron melts Wr't " Gold Silver Steel Brass Copper Glass DEGREES. 3,477 " 3,981 " 2,587 " 1,250 " 2,501 " 1,897 " 2,550 ■•' 2,377 Platinum Lead Zinc Cadmium Saltpetre Tin Sulphur Potassium DEGREES. melts 3,077 " 600 " 741 " 602 " 600 " 420 " 225 '• 135 Table of Hollow Cylindrical Columns, for Large Mills, with Cores. Diameter \ iaineter Diameter Diameter Length of No. of Cu- Total of Uolumn of aCros — of tue Core of the Core the bic Inches Weight of at small Section in at riuall at the Column in in the Column in end. the miJ'le end. middle. Feet Column. Pounds. Inches. Inches. Inches. Inches. 7 11 2 n 12 8,944 2,236 8 12 2 4 12 10,4(10 2,600 9 14 3 n 14 13,849 3,462 10 16 4 10 16 33,744 8,438 It has been fully tested that cast iron columns of a large dimen- sion witli a core are much stronger than without it. This, no doubt, arises from the fact that the case affords a sensible spring in case of a sudden strain, and therefore less liable to fracture. i&3 STEAM AXD THE STEAM-ENGINE. STEAM AND THE STEAM-ENGINE. Nominal Power of S team-Engines. The usual estimate of the dynamical effect per minute of a horse, called by engineers a horse-power, is 33,000 lbs. at a velocity of 1 foot per minute ; or the effect of a load of 200 lbs. raised by a horse for 8 hours a day at the rate of 2^ miles per hour; or 150 lbs. at the rate of 220 feet per minute. To determine the Diameter of a Cylinder for an Engine ot a required Nominal Power. Divide 5,50.J by the velocity of the piston in feet per minute, and the quotient equals the number of square inches to a horse- power, which multiply by the reejuired number of horse-power, and the product is the cylinder's area, against which, in the Table of Areas, is the diameter required. Example. — Required the diameter of the cylinder for a 25- horse engine, with a velocity of 230 feet per minute. ""^ ^ 23.913 X 25 = 597.825 inches area; or 27^ inches diame- ter, nearly. oportiona te Velocities for the Pistons of Stati( ary Condensing Engines. Length of Stroke, Velocity iu Feet Number of Revolutions iu feet. per Miuute. pe r Minute. 8 256 16 7 245 17^ 6 240 20 5i 23G.', 211 5 230' 23 ^ 220.1 21J 26! 4 21-1" 3i 2(J3 29 3 l'.»2 32 21 177i 35J 2" 160 40 To estimate the Amount of EfTfectivo Power of an Engine by an Indicator. Multiply the area of the piston in s(jnare inches by the aver- age force of tho steam in lbs., and by the velocity of the piston in feet per minute ; divide the ])roduct by 33,000, and 7-10 of the quotient cijunl the effective power. STEAM AND THE STEAM-ENGINE. 183 ExAjrPLE. — Suppose an engine, -with a cylinder of 37 J inches diameter, a stroke of 7 feet, and making 17 revolutions per min- ute, or 238 velocity, and the average indicated pressure of the steam 16.73 lbs. per squai-e inch : required the effective power. 1104.4G87 inches X 16.73 lbs. X 233 feet 133.26 X 7 Axea = ' 3:i000 10 ^93.282 horse-power. To find the Greatest Quantity of Water required. for Steam. Multiply the area of the cylinder in feet by the piston's ve- locity in feet per minute, add 1-10 for cooling and waste, divide the sum by the volume of steam compared to the volume of water (as per Table of Pressiires), and the quoti.ent equals the quantity in cubic feet per minute. Note. — For single-acting engines only about half the quantity is required. Example — Eequired the quantity of water for steam to supply an engine, whose cylinder is 2 feet diameter, the jiiston's velocity 214 feet per minute, and the pressure of steam 18 Ib.s. per sqiiare inch, including the pressiire of the atmosphere. Area= 3.1116x214 = 672.3 + 67.23 = 739.53 ^ 1411 = .523 cubic feet per minute. To find the Quantity of Water required for Injection. From 1212 subtract the temperature of the condensed water ; divide the result by the temperature of the condensed water minus the temjierature of the cold water ; multiply the quotient by the quantity of steam in cubic feet in a given time, and the product equals the quantity of water in cubic inches. Example. — Reqiiired the quantity of water at 60'^, to condense 50 ) cubic feet of steam to water at 95^ Fahrenheit. "^^ Ei = 31.9 X 500 = 15950 cubic inches. or, 159:>0 X .00058 = 9.251 cubic feet. Proportions of Cylinder, Condenser, and Air-Pump. The length of the cylinder, and consequently the stroke of the piston, ought not to be less than twice the cylinder's diame- ter ; as then the least surface is exposed in proportion to the capacity : and the longer the stroke, the greater the effect, from the principle of expansive force. The capacities of the condenser and air-pump are each \ the capacity of the cylinder. 1S4 STEAM AND THE STEAM-ENGINE. Advantages derived, from the Expansive Properties of Steam. If stoain of a uniform elastic force be employed throughout the ■vs'liole ascent or descent of the piston of a steam-engine, the a:u >unt of effect is as the quantity expended. Biat suppose the steam to be shut off at any portion of the stroke, say, for in- stance, at one-half, it expands by degrees until the termination of tie stroke, and then exerts half its original force ; lience an accumulation of effect in proportion to the quantity of steam. To obtain or calculate the Amount of Effect. Divide the length of the stroke by the length of the space into which the dense steam is admitted, and find the hyperbolic logarithm of the quotient, to which add 1, and the sum is the ratio of the gain. Example. — Suppose an engine with a stroke of G feet, and the steam cut off when the piston has moved through 2 : required the ratio of iiniform elastic force. G^2 = 3; hyperbolic logarithm of 3 = 1.0986 + 1=2.0986, ratio of effect; that is, supposing the whole effect of the steam to be 3, the effect by the steam being cut off at J = 2.0986. Table of Hyperbolic Logarithms. Ko. Logarithm, No. 3.V .22314 .40546 n .559G1 4' .G9314 i\ .81093 4.1 .91G29 n l.OllGO 5 •1.098G1 5V 1.178C5 5i Logarithm. No. 5} 1.25276 1.32175 6 1.38G29 6} 1.44G91 4 1.50507 1.55814 7 1.G0943 7.} 1.G3822 7.V 1.70474 n Logarithm. No. i 8 1.74919 1.79175 8.\ 1.83258 9" 1.87180 9.! 1.90954 10" 1.94591 12 1.98100 14 2.01490 IG 2.047G9 18 Logar'm. 2.07944 2.14006 2.19722 2.25129 2.30258 2.48490 2.G3905 2.77258 2.89037 LOCOMOTIVE ENGINE!. Tabic showing the Circumforonces of different Driving Wheels. l^iam. of Wheel. J.<-n^tli of ( iriuiii. Diam. of Wheel. Lougth of Circum. ft. in. feet. ft. iu. foot. 4 12.5GG 6 G 20.419 4 G 13.927 7 21.990 5 r..7()7 7 G 23.5G1 5 G 17.278 8 25.132 G 1;h.849 I STEAM AND THE STEAM-ENGINE. 185 Table containing the Velocity of the Pistons, that of the Circumference of the Driving Wheels being taken as 1. ID 9 B o ** c -•■si in, 23 19 18 17 16 15 14 11 12 Diameters of Driving Wheels. 4ft. Oin. 0.2652 0.2519 0.2386 0.2254 0.2121 0.1989 0.1856 0.1724 0.1591 4ft. Gin. 0.2393 0.2273 0.2153 0.2034 0.1914 0.1795 0.1675 0.1555 0.1436 5ft. Oin. 0.2122 0.2016 0.1910 0.1803! 0.1697 0.1591 0.148") 0.1379 0.1273! 5ft.6in. 0.1929 0.1832 0.1736 0.1640 0.1543 0.1447 0.1350' 0.1254 0.1157 6ft. Oin. 0.1768 0.1679 0.1591 0.1503 0.1415 0.1326 0.1237 0.1149 0.1061 6ft. 6in. 0.1632 0.1550 0.1468 0.1387 0.1305 0-1224 0.1141 0.1061 0.0979 7ft. Oin 0.1516 0.1440 0.1364 0.1288 0.1213 0.1137 0.1061 0.09S^5 0.0909 7ft. 6in. 0.1414 0.1343 0.1272 0.1202 0.1131 0.1060 0.0990 0.0919 0.0848 8ft. Oin. 0.1326 0.1259 0.1194 0.1127 0.1061 0.0994 0.0928 0.0862 0.0796 Application of this Table for finding the Tractive Power of Locomotive Engines. Multiply the sum of the areas of the two pistons by the effec- tive pressure of the steam in i^ounds, and further, that product by the co-eflicient in the table (belonging to its driving wheels and stroke of the pistons), and this new product will be the traction of the engine in pounds. Example. — A locomotive engine to have 5 feet 6 inch driving wheels, cylinders of 13 inches diameterby 18 inches stroke, and the effective pressure of the steam to be 40 lbs. on the square inch : what is its traction ? (2 X 132.66)40 X 0-1736 1842.39 lbs. of traction. If it be required to know the number of tons the engine is able to draw on a level, divide its traction by the friction in pounds. If the engine is to go up inclines, then add to that friction the gravity in pounds due to a ton on that incline, and use this sum as a divisor for the traction, the quotient will be the number of tons the engine is capable to rise up that incline with. In both cases is the weight of the engine and its tender in the quotient included. Explanations. — By effective pressure is understood the pressure of the steam above the pressure of the atmosphere, less the num- ber of pounds necessary to keep the engine by itself just in motion. Frid'ion, the power necessary to move a mass along, which is generally taken to be on railroads equal to 10 lbs. for every ton. Gravity, the power to overcome the tendency of a mass or load to descend an incline, being always equal to the quotient of the 186 STEAM AND THE STEAM-ENGINE. product of the load and height of the incline, divided by the length of the incline. Therefore the above engine would draw 1842.39 — r^^ — = Ibi tons on a level; and on an inclined plane, say as 1 in 300. Friction = 10 lbs. «"'*y = lJ<|l»=7.,CGlta. 17.466 lbs. ,, 1842.39 ,«^ ^ , Consequently ^^^ =105.5 tons up an incline of 1 in SOO. If the weight of the engine with its tender bo taken at 18 tons it will draw a net gross load of 166 tons on a level, and 87.5 tons up an incline of 1 in 300. To calculate for the Travel of the Valves, ThroTir of Eccentrics, &c. Example. — Suppose, in a locomotive engine, the valves require a travel of 3^ inches; the top lever, or lever immediately connect- ed with the valve spindle, being 9.\ inches, and the bottom lever 8 inches: what must be the throw of eccentrics ? ^•'[^^^ = 3.243 inches, or 31, nearly. Note. — The travel of a valve equals the width of the two steam openings, plus the lap of the valve over each oi)cning; and the whole length of its movement or face ujx)!! the cylinder equals twice the travel of the valve, jjIus the distance between the two steam openings. To ascertain the Amount of Weight or Pressure on the Safety-Valve of a Locomotive Engine. Divide the length of the lever by ilio distance from its centre of motion to centre of valve, and multiply the iudi(!at(Ml pressure on the sjjring lialance by the quotient, to whieli add the action or pressure of the levf^r and spring balanci'; divide the sum by tlie area of the valve, and the quotient equals the pressure on each inch of tin; boiler. E.VAMPI.K. — Sujiposo an engine with valve levers of 22j inches in lengtli, and the distance from the ]iin to centre of valve 2J iiielies; th(^ action of the lover aiul si>riiig balance 5 lbs. ; the in- dicated ])ressuni 50 lbs., imd tlie area of the valve 7 inches: re- quired tlie pressure on each sipiare incdi. 22.5-1-2.5 = 9 ; aud^^-^JJ-^ = 65 lbs. per square inch. STEAM AND THE STEAM-ENGINE. 187 To determine the Pressxire of Steam equal to the re- sistance of a given load, by a Locomotive Engine. It is ascertained, by exiieriment, that 6 lbs. per ton of tho engine's weight is expended in overcoming the friction of its l^arts when unloaded; 9 lbs. per ton of gross load for horizontal traction and additional friction caused by the load; and 14.7 lbs. per square inch, the pressure of the atmosphere. Hence, to 9 times the gross load of the train in tons, add the friction of the engine ; multiply the sum by the diameter of the driving wheels in inches; divide tho jiroduct by the cylinder's capacity in inches, and the quotient, plus 14.7, equals the pressure of the steam in lbs. per square inch on the piston. .Ex.\MPiiE. — Required the pressure per square inch on the pis- ton's area, to overcome a loa-t of 120 tons gross on a level line, the engine being 13 tons, driving wheels 5^ feet, cylinders 13 inches diameter, and length 18. 120 — 13 = 107 X 9 =^ 1080; and 13 X 6 = 78, the force of traction; 13- X 18 = 3042. rj^^^ 1080 + 78 X 66 . 3042 : 25.12 + 14.7 = 39.82 lbs. per sq. inch. Table of the Areas of Cylinders from 9 to 15 Inches Diameter. Diam. of Cylinder- Area of Cylinder. Diam. of Cylinder. AreaofC^'linder. Inches. Siiuare Inches. Inches. Square Inches. 9 G3.5S 12^ 122.65 10 78.5 13 132,. 66 101 86.56 13^ 143.02 11 95.01 14 153.96 lU 103.84 ^^ 165.04 12 113.07 15 176.62 Note. eters. -The areas of cylinders are as the squares of their diam- Various modifications have lately been added to the list of im- provements in locomotive engines, and among the most efficient is that of using steam more or less expansively, as required. The arrangement is such, that the quantity of steam, of uniform density, is immediately changed to suit either the load or incli- nations of the line. Another essential improvement is that of insuring a unifornj equilibrium of the engine, in case of fracture in the front axle; siich an occiirrence being the only real cause of fear in running a six-wheeled engine. Ib8 STEAM AND THE STEAM-ENGINE. Table of Dimensions of the Principal Parts of Loco- motive Engines. POBTIONS OF THE ENGINES. Oylinders and sienm passages. Diameters of cylinders Distance from cen. to cen. of do. Length of stroke " steam and eduction ports Width of steam ports " eduction ports Breadth of bridges betw. ports Cylindrical paH of the boiler and tubes. Diameter of the boiler Length " " " " tubes Diameter " " Thickness of tubes bywire gauge Number of the tubes Inside and outside fire boxes. Length of inside fire box Breadth " " Height above the fire bars Area of fire grate Length of outside fire box Breadth " " Thickness of plates Ex. thick, where tubes inserted. .Sy/to/.-e box, cJiimney, ami blast pipe. Length of smoke box, inside. . . Breadth " " Thickness of plates Diameter of chimney Height to top of do.' from rails. Diameter of blast pipe WliPiis, .vprini/s. d'c. Diameter of driving wheels .... " hading *' ... " fniiliiig " Breadth of tires Thickness, average Diameter, of axlo bearings Length " " ... " driving-whc(!l springs. Breadth of " " . GAUGE OF RjOLWAY. 4 Ft. 8 >i In- 6 Feet. 7 Feet. ft. ins, ft. ins. ft ins. 1 1 1 2 1 3 2 5 2 5 3 1 6 1 6 1 8 11 11 lU 1.1 n u o| 2i 2| o§ o| 3 4 3 7 4 8 8 6 8 6 8 5 8 11 9 2 2 2 No 14 No 14 No 14 121 131 137 3 3 4 3 8^ 3 7 3 5 3 11 3 10 3 10 3 11 10 9 11 4 14 8 3 6 3 10 4 3 4 1 4 4 6 o! 03 ^ 01 o| 2 1 2 1 2 2 4 2 4 21 5 ^ 1 1, 1 2 1 4 13 4 13 G 14 10 31 3.1 3| 5 r, (\ 7 4 4 4 3 f. 4 4 ry\ r>), 5, 1] ]! 1; 3i 3- 4 f!3 (',■ 7 2 9 2 9 2 G a;. 3i 3i BTEAM AND THE STEAM-ENGINE. 189 POBTIONS OF THE ENGINES. iVheds, springs, cf'c Number of plutes Length of leading wheel-spring's ±>readth of " Kumber of plates ( Trailing-wheel springs. Breadth of do. Number of plates i Diameter of safet.y valves " piston rods " valve spindles . . . " crank pins " pump rams Extreme breadth of outside frame " length GAUGE or KAILWAT. 4 Ft. 8'^ In. 5 Feet, ft. 1 at I and 12 at 5 5-16 2 5 3^ i at I and 14 at 2 1 at f and 6 at 5-16 3.1 31 6 18 2 H 2' 5 ^ ft. 7 Feet. 14 at 55-161 2 5 ^ 1 at fand 14 a t 5-16 2 2 3^ 1 at land 6 at 5-16 1 Sh 21-161 U 5-1 2 6 8^ 18 ^ ft. iug. 2 at I and 10 at 5-16 2 3 3i 2 at I and 10 at 5-16 2 3 3} 2 at I and 8 at 5-1 6 4 8 20 2} n 21 91 4 Table showing tho Approximate of Useful Effect of an Ordinai'y Locomotive Engine at different Velo- cities. Load in Tons. Miles per hour. Miles pT hour. Load in Tons. 25 30.90 10 250 50 25.15 12^ 184 75 22.54 15 138 100 18.18 17^ 106 125 15.98 20 83 150 14.29 221 65 175 13.28 25 50 200 11.20 27^ 38 225 10.77 30 28 The increased resistance to traction on ascending inclined planes is as the increased gravity of the load, caused by the in- clination of the plane ; or as the length of the plane to the per- pendicular height. Hence, divide 2,240 (or the niiraber of lbs. in a ton) by the inclination of the plane to 1 or unity, to the quo- tient of which add 9, and the sum equals the total resistance, in lbs., per ton upon the plane. 190 STEAM AND THE STEAM-ENGINE. Example. — Required the resistance to traction, per ton, on an inclined railway rising 1 in 300. ^ = 7.47 + 9 = 16.47 lbs. per ton. Usefnl effect of a single-acting i^nrnping engine, with a con- sumption of 1 bushel of coals: Diameter of cylinder, 5 feet, 3 inches. Length of stroke, 7 " 9 Stroke of pump, G '« 9 Number of strokes per minute, 6.1. Effective pressure, per square inch, of piston, 13.4 lbs. "Water lifted 1 foot high, per minute, 38,063,288 lbs. Table Showing the Number of Revolutions of the Dbtvino Wheels, OR Strokes of the Piston, pkr Minute, while the Engine is PERFOBMINQ A KNOWN NUMBER OF MiLES PER HoUR. Dlam. of Wheel 4 ft. Diam. of Wheel I Wheel 4 ft. ( lD.I Sft. Diain. of DUm. of Diam. of Wlieel Wheel ft. G In. 6 It. No. of revol. or Btrukea per mln. No. of rcvol. or BCrokea permin. 280. 315. 330. 3H5. 420. 455. 490, 52.x 5or». 595. G30. G65 700. 31 63 94 126 157, 189. 21|221. 24 252, 27284 30315, 33 347, 36 379, 39 416 42 442 45 473. 48 505 51 536. 54 568. 57 600. 60 031. .59 28. ,17 56. ,76 84 ,36112. 95140. 54 168. 13 196. 72 224. 30 252. 90 280 49 308. 08 336. 67 364 19 392 85 420. r>0 4 18. 89 477. 60 504. 19 532. 7B 560. 031 25. 06; 50. 09, 76. 12 101. 20 127. 18 152. 21 177. 24 203. 27 229. 30 254. 3.1 28). 36 305. 39 331. 42 356. 50 372 48 407. 01 432. 51 458. 57 483. 63 509. I 47 23 95 46 42 70 70 93, 37 116 85 140, 29 163, 76,U6, 23 210 75 233 17 256, 64 280, 11 303, 58 326, 05 350, 60 373, 99 396. 55 420. 93 443, 50 466. DiAm. of DlAm. of Wheel I Wh-,el 6 ft. 6 !n.| 7 ft. No. of I No. of revol. or revol. or strokes I strokes permin. I per niin. 34 21.55 68 43.10 64.65 86.20 70107.75 04 129.30 38 150.85 72|l72.40 06 19.3.95 .40215.50 74 237.05 08 258.60 42 280 15 76 301.70 10 323.21 44 311 80 78 366. 35 12.387.90 46 409.45; 80 431.00 20 40 60 80 100 120 140 160 180 200 220 240 260 280 300 320 340 360 380 400 DIam. of. Dl;tm.uf Wheel I Wheel 7 ft, 6 in. 6 ft. No. of revol. or strokes permin. No. of revol. or strokes p«rmlD. 17 35, 52 75. 87, 18.67 37.34 56.01 74.68 93 35 112.02105 130.69 122 149.36140. 168.03157 186.70175, 205.37192. 224.04 210 242.71227. 261.38 245 280.05 262 298. 72 280, 317.39 297. 336.06 315 ).U.73 332. 373.40 350, ES.S. 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 Note. -To find the velocity the piston is travelling at in feet per minute, multiply tlie number of rfvolntions of its driving whccK in the tablo, l)y twice the longtli of its stroke in foet. STEAM AND THE STEAM-ENGINE. 191 Example. — "What is the speed of the piston of an engine with 6 feet driving wheels and 15-inch stroke, when going at the rate of 50 miles an hour? By means of the table : 233.4 revolutions X ("^^^ =583.5 feet per minute. The number of revolutions of driving wheels are inversely as their diameters, and in direct proportion to the number of miles performed. Example. —How many revolutions have the driving wheels of an engine to make when it is going at 95 miles an hour, their diameter being 9 feet 6 inches ? According to the table, a 4-foot wheel would have to make 665.57 revolutions, therefore 9.5:4 :: 665.57:4x665.57 „„,, - — — - — = 280 revolutions, y. The driving wheels of an engine make 35.03 revolutions when going at the rate of 5 niiles an hour, how many will they make when going at 9 miles ? —^ — =63.05 revolutions. To compute the Pressiire of Steam. When the Height of the Column of Mercury it will Support is given. RtTLE. — Divide the height of the column of mercury in inches by 2.0376, and the quotient will give the pressure per square inch in pounds. Example. — The height of a column of mercury is 203. 76 inches ; what pressure per square inch will it contain ? 203.76-^2.0376 = 100 lbs. To compute the Temperature of Steam. RrLE.^Multipl}' the Gth root of its force in inches of mercury by 177, and subtract 100 from the product, the remainder will give the temperature in degrees. Example. — When the elastic force of steam is equal to a pressure of 49 inches of mercury, what is its '^emperature ? Note. — To extract the 6th root of a number, ascertain the cube root of its square root. y of 49 = 7, and 3 ^/ of 7 = 1.9129. Hence 1.9129 X 177 — 100 = 238=. 58. 192 STEAM AND THE STEAM-ENGINE. To eomputa tho Pressure of Steam in Inches cf Mercury. WJien the Temperature is given. RtTLE. — Add 100 to the temperatiire, divide the sum by 177, and the 6th power of the quotient will give the pressure in iaches of mercury. Example. — The temperature of steam is 312°; what is its pressure ? 100 + 312 ^ 2.3277, and 2.3277« = 159 ins. 177 Note. — To involve the Gth power of a number, square its cube. To compute the Specific Gravity of Steam com- pared with Air. Rule.— Divide the constant number 830.11 (1700 X. 4883) by the volume of tlie steam at the temperature of pressure at which the gravity is required. Example. — The pressure of steam is GO lbs., and the volume of it is 470; what is its specific gravity ? 830.11 + 470 = 1.766. Note. — The specific gravity of steam compared with water = .00058823. SLIDE VALVES. /Ill Diineiisions in Inches. To compute how much Lap must be given on the Steam Side of a Slide Valve, to cut off the Steam at any given Part of the Stroke of the Piston. Kiirj:. Fm)Iu tin; Icii^^th of strolui of ]iist<>n sulitnict the h>ngth of the stroke that is to he; iiiailc! l)cf'ori! tlii> stt'iun is imt oft'; di- vide the r(^in;iiiidiT by till' Ktrol<(^ of thi- ])iston, and extract the square root of the quotiiiil. Multiply this root bylialf the tlirow of the valve, from the ]irodnct subtract half the lead, and the re- mainder will give the laji re(piired. ExAMPi.K. Having stroke of piston 60 ins., stroke of valve 16 ins., laj) iipou exhaust side }, in. - X-'.Vl of \i\\\v. stroke, lup uj)on steam siile 3,J ins., lead 2 ins., steam to be cut off at 5-6 the Htroke; what is the lap? 60— -of 60 = 10. '.'* .166. ^/.166r=.408. .408x^^-^3.264, 6 60 2 2 and 3.264 — - = 2.264 ins. or the laj) half the h«id. u STEAM AND THE STBaM-KNGINE. 193 To compute the Lap required on the Steam Side of a Valve, to cut the Steam off at various Portions of the Stroke of the Piston. Value wUhout Lead. Distance of tlie pistou from the end of its strolie when the steam is cut oil', in pans of the length of its strolie. 1 -S_ i 7 1 5, 1 1 1_ 1 3 13 3 85 4 5i IT 8 T3 !J5 ofTheXoke! -354 .3'23 .286 .27 .25 .228 .204 .177 144 .102 Illustkation. — Take the elements of the preceding case. Under 1-6 is .204, and .204 X 10 = 3.2G4 ins. lap. When the Valve is to have Lead. — Subtract half the proposed lead from the lap ascertained by tne table, and the remainder will be the proper lap to give to the valve. If, therefore, as in the last case, the valve was to have 2 ins. lead, then 3.264 — 2 -j- 2 = 2.264 ins. To compute at what Part of the Stroke of the Pis- ton any given Lap on the Steam Side will cut off the Steam. KuLE.— To the lap on the steam side add the lead ; divide the sum by half the length of throw of the valve. From a table of natural smes find the arc, the sine of which is equal to the quotient; to this arc add 90°, and from their sum subtract the arc, the cosine of which is equal to the lap on the steam side, divided by half the throw of the valve. Find the cosine of the remaining arc, add 1 to It, and multiply the sum by half the stroke of the pis- ton, and the product wuU give the length of that part of the stroke that will be made by the piston before the steam is cut oflf. Example. - -Take the elements of the preceding case. ;„ To =-5312.5; sin. .53125 = 32° 5'; 32° 5 -f 90° = 122° 5'; It) —^ £i 2. 25 -I- 8 = .28125 = cos. of 73° 40'; then 122° 5' — 73° 40' = 48° 25; cos. + 1 = 1.66371, which X — = 50 ins., or 5-6 stroke. To compute the Distance of a Piston from the End of its Stroke, when the Lead produces its Effect. BuLE.— Divide the lead by the width of the steam port, both in inches, and term the quotient sine; multiply its correspond- ing versed sine by half the stroke, and the product will give the distance of the piston from the end of its stroke, when steam is admitted for the return stroke and exhaustion ceases. 9 191 STEAM AND THE STfiAM-ENGINE. Example. The stroke of a piston is 48 ins., wultli of port 2\ ins., and the lead i in.; what will be the distance of the piston from the end of its stroke when exhaustion commences? .5-^2.5:=.2 = sino, and versed sine of .2 = .U202. Then .0202 X ~ = .4848 ins. 2 To compute the Lead, when the Distance of a Piston from the End of its Stroke is given. Rule. — Divide the distance in inches by half the stroke ia inches, and term the quotient versed sine; multijjly the cor-- responding sine by the width of the steam port, and the product will give the lead. Example. — Take the elements of the preceding case. .4848— -24 = .0202 = versed sine, and sine of versed sine .0202 = .2. Then .2 X 2.5 = .5 inches. To compute tho Distance of a Piston from the End of its Stroke, when Steam is admitted for its return Stroke. Rule. — Divide the width of the steam port, and also that width less the lead, by half the stroke of the slide, and term the quo- tient versed sines first and second. Ascertain tlieir correspond- ing arcs, and multiply tlie versed sine of the difference between the first and second by half the stroke, and the product will give the distance required. Portion of the Stroke of a Piston at which the Ex- hausting Port is closed and opened. Lap on the Kclumsl Side of (he ['aloe in Parts of Us Throw. Portion of Stroke at which the Steam is cut ofif. Lap. i 7 •i I X ■I 1 t'l 1 8 1 1 u h A f .178 .101 .143 .126 .109 .093 .074 .053 1 1 li .13 .lis .1 .0X5 .071 .058 .013 .027 • ^•» .113 .11(1 .085 .0(5!) .053 .043 .033 .024 .002 .082 .067 .055 .041 .033 .022 .Oil B h .033 .020 .019 .012 .008 .004 .001 .001 ^^r .00 .052 .04 ,03 .022 .015 .008 .002 ■»% .073 .000 .051 .012 .033 .023 .013 .004 .002 .082 .067 .055 .044 .033 .022 .011 STEAM AND THE STEAM-EXGINE. 195 The units in the columns of the table marked A express the distance of the piston, in parts of its stroke, from the end of the stroke when the exhaust port in advance of it is closed ; and those in the columns of the table marked B express the distance of the piston, in parts of its stroke, from the end of its stroke when the exhaust port behind it is opened. Illustkation.— A slide valve is to cut off at 1-6 from the end of the stroke of the piston, the lap on the exhaust side is 1-32 of the stroke of the valve (1(3 ins. „ and the stroke of the piston is 60 inches. At what point of the stroke of the piston will the exhaust port in advance of it be closed, and the one behind it opened ? Under 1-6 in table A, opposite to 1-32, is .053, which X 60, the length of the stroke, = 3.18 ins. ; and under 1-6 in table B, oppo- site to 1-32, is .033, which X 60 = 1.98 inches. If the lap on the exhaust side of this valve was increased, the effect would be to cause the port in advance of the valve to be closed sooner, and the port behind it oj^ened later. And if the lap on the exhaust side was removed entirely, the j^ort in advance of the piston would be shut and the one behind it open at the same time. The lap on the steam side should always be greater than that on the exhaust side, and the difference greater the higher the velocity of the piston. In fast-running engines, alike to locomotives, it is necessary to open the exhaust valve before the end of the stroke of the piston, in order to give more time for the escape of the steam. To ascertain the Breadth of the Ports. Half the throw of the valve should be at least equal to the lap on the steam side, added to the breadth of the port. If this breadth does not give the required area of j^ort, the throw of the valve must be increased until the required area is attained. To compute the Stroke of a Slide Valve. KuLE. — To twice the lap add twice the width of a steam port in inches, and the sum will give the stroke required. Expansion by lap, with a slide valve operated by an eccentric alone, cannot be extended beyond ^ of the stroke of a piston without interfering with the efficient operation of the valve; with a link motion, however, this distortion of the valve is somewhat compensated. When the lap is increased, the throw of the eccen- tric should also be increased. "\^^len low expansion is required, a cut-off valve should be re- sorted to in addition to the mam valve. 196 STEAM AND THl-] STEAM-ENGINE. POWER OF STEAM. Mr. Tredgokl gives the following table, which will show how the power of the steam as it issues from the boiler is distributed. In a Non-Condensing Engine. Let the jiressure on the boiler be 10.000 Force required to produce motion of the steam in the cylinder will be 0.069 Loss by cooling in the cylinder and pipes 0.160 Loss by frictiiin of the piston and waste 2.000 Force required to expel the steam into the atmosphere. 0.069 Force expended in opening the valves, and friction of the various parts 0.622 Loss by the steam being cut off before the end of the stroke 1.000 Amount of deductions 3.920 Effective pressure 6.080 In a Condensing Engine. Let the pressure on the boiler be ^10.000 Force required to produce motion of the steam in the cylinder 0.070 Loss by cooling in the cylinder and pipes 0.160 Loss by friction of the jtiston and waste 1.250 Force required to expel steam through the passages. .0.070 Force rec^uired to open and close the valves, raise the injection water, and overcome the friction of the axes 0.630 Loss by the steam being cut oflf before the end of the stroke 1.000 Power required to work the air pump 0. 500 Anion lit of deductions 3.680 Effective pressure 6.320 If we now suppose a cylinder whose diametpr is 24 inches, the area of this (;yliuder, and cousciiiiciitly the area of the piston, in square inches will be 24'JX.7854 = 452.39. Let us also make the supjiosition that steam is admitted into the cylinder of such power as exerts an effective pressure cm the ])ist()n of 12 lbs. to the s(piaro inch; therefore 4')2.3"J X 12 = rA2H.(',H lbs., tlnj wholi! I'ortie with wliicdi the piston is pressed. If we now sui)i)ostuitioii. 1 scpiare foot of grate* surface, at a combus- tion of i;5 lbs. coal i)er hour, will evaporate 2 cubic feet of salt water j)er hour. A sepians foot of heating surface, at the above combustion of fuel, will evai>orate from 4.33 to 5.33 lbs. of salt water per Imur; and at a (loiiibustinn of 40 lbs. coul ]ier liour (as u])on the West- ern rivers of the U. S. ), from 10 L^ = .255 in. StaiJ Bolts. Iron stay bolts, \ ins. in diameter, screwed into a copixr plate g thick, drew at a strain of 18,2f'.() ll>s. A liki- stay bolt, sc.n^wed and riv<'ted into an iron plate, drew at a strain of 28, TOO lbs. A like stay bolt of copper, screwed and riveted into a cojjpor plate, drew at a strain of 10,205 lbs. Hence, stay boitn when scrowod and riveted are J stronger than when screwed aU)Ue. MEASURES AND WEIGHTS. 205 METRIC SYSTEM OP MEASURE J WEIGHTS. ACCOEDING TO AcT OF 1866. AND Equivalents of Old and New IT. S. Measures. Length. Surface. Inch Foot Yard 1 Chain Furlong Mile Metres. .02540005 .3048006 .9144018 20.1168396 201.168396 1609.347168 Volume. 1 Fluid Dram 1 Fluid Ounce 1 Fluid Pound 1 Gill 1 Wine Pint 1 Dry Quart 1 Wine Quart 1 Wine Gallon Litres.* : .f036967 : .0295739 : .35488656 : .1182955 : .4731821 1.1012344 : .9463642 : 3. 7854579 Square Metres. 1 Inch = .000645161 1 Foot = .092903184 1 Yard = .836128656 1 Eod = 25.292891844 1 Rood = 1011.71507376 1 Acre ^ 4046.86269501 Weight. Grammes. 1 Grain = .0648004 1 Scruple == 1.296008 1 Pennyweight = 1.5552096 1 Dram = 3.888024 1 Ounce (Troy) =31.104192 1 Ounce t =28.350175 1 Pound =453.6028 1 Ton =1016070.272 Note. — A square metre is 1549.99G9 square inches, but by Act of Congress it is declared to be 1550 square inches; hence the litre (cubic decimetre) =61.023377953 cubic inches. In the Act of Congress, a litre is declared to be 61.022 cubic inches, which is erroneous, as here shown, by the .001 -)- of an inch. Measures of Length. Denominations and Values. Equivalents in use. Mj'riametre. Kilometre. . . Hectometre Decametre. . Metre Decimetre . . 10,000 metres. 1.000 100 10 1 -j^ofa 6.2137 miles. .62137 " or 3280 ft. & 10 ins. 328 ft. and 1 inch. 393.7 inches. 39.37 " 3.937 " Centimetre. . Millimetre. . 100 1 <( >( TOGO .3937 " .0394 " * G1.023 cubic inches. t AvoirdupoiB. 206 MEASURES AND WEIGHTS. Measures of Surface, Denomiuatious and Values. Equivalents in use. Hectare Are Centare 10,000 sq. metres. 100 " 1 (( (( 2.471 acres. 119.6 square yards. 1550 square inches. Measures of Volume. Denominations and Values. Equivalents iu u e. Names. No. of Litres. 1,000 100 10 1 iV . 1- 1 00 Tooo Cubic Measure. Dry Measure. Liq. or Wine Measure. Kilolitre J orStere j Hectolitre Decalitre . . Litre Decilitre . . Centilitre . . Millilitre. . . 1 cubic metre 10 . 10 " decimetres 1 " 10 " centimetres 1 " 1.308 cub. yds. 2bh., 3.35 pks. 9.08 quarts. .908 " =5.1022 cub. ins. .6102 " " .061 " " 264. 17 gals 26.417 " 2.6417 " 1.0567 qts. .845 gill. .338 fld. oz .27 "drm Weights. Denominations and Values. Equiv. in use. , Names. Number of Grammes. Weight of Volume of Watt>r at its Maximum Density. AvoirdupolB Weight. Millii^r or Tonneau Quintal 1.000.000 lOO.OO ) 10.000 1,000 100 10 1 I 10 .So logoff 1 cubic metro. 1 hectolitre. 10 litres. 1 1 decilitre. 10 cubic centimetres. 1 1.1 Iff 10 cubic millimetros. 1 (i (1 2204.6 Ib.s. 220.46 '• Myriagramme .... Kilogram, or Kilo. Hectogramme. Dc'cagramme Gramme 22.046 " 2.2046 " 3.5274 oz. .3527 " 15.432 gra. Decigramme Centigramme Mllligramnjc 1.5432 •' .1543 " .0154 " For measuring Rurfaces, the scjuaro Docami'tre is used under the tiriii of Arr; the Hi'ctar«s or 100 Arcs, is ciiual to about 2 acres. The Unit of Capacity is the cubic. Decimetre or Ijilre, and tho HcrieH of nieiiHurcH is formed in the same way as iu tho case of the tabic of lengths. ALLOYS AND COMPOSITIONS. 207 The cubic Metre is the unit of measure for solid bodies, and is wrmed Stere. The Unit of Weight is the Gramme, which is the weight of one cubic centimetre of pure water weighed in a vacuum of 4"^ Centi- grade, or 39 \ 2 Fahrenheit, which is about its temperature of maximum density. In practice, the terra cubic Centimetre, abbreviated C. C, is used instead of Millilitre, and cubic Metre instead of Kilolitre. ALLOYS AND COMPOSITIONS. Compositiou for Welding Cast Steel. Borax, 10 parts; sal-ammoniac, 1 part. Grind or pound them IroTighly together; fuse them in a metal pot over a clear tire, con- tinuing the heat until all spume has disappeared from the sur- face. When the liquid is clear, pour the composition out to cool and concrete, and grind to a fine j^owder; then it is ready for use. To use this composition, the steel to be welded should be raised to a bright yellow heat; then dip it in the welding powder, and again raise it to a like heat as before; it is then ready to be submitted to the hammer. Fusibla Compounds Compounds. Zinc. 33.3 Tin. 25 19 12 Lead. 25 33.:^ 31 25 Bism'h. Cadm. Rose's, fusing at 200' 50 33.4 50 50 Fusing at less than 200° Newton's, fusing at less than 212" Fusing at 150° to 160° 13 Soldering Fluid for Use with soft Solder. To 2 llui 1 oz. of nuiriatic acid add small jiieces of zinc until bubbles cease to rise. Add half a teaspoonful of sal-ammoniac and 2 fluid oz. of water. By the application of this to iron or steel, they may be soldered without their surfaces being previously tinned. Babbitt's Anti-Attrition Metal. Melt 4 lbs. copper ; add, by degrees, 12 lbs. best Banca tin, 8 lbs. regulus of antimony, and 12 lbs. more of tin. After 4 or 5 lbs. tin have been ad lerl, reduce the heat to a dull red, then add tiie remainder of the metal as above. This composition is termed hardening; for lining, take 1 lb. of this hardening, melt with it 2 lbs. Banca tin, which produces the lining metal for use. Hence, the proportions for lining metal ar'j i lbs. of copper, 8 of regulus of antimony, and 9 J of tin. 208 TEMPERING. TEMPERING. Tlio article after being completed is liurdenecl by bein;^ heated gradually to a bright red, and then phinged into cold water; it ia then tempered by being warmed gradually and equably, either over a fire, or on a piece of heated metal till of the color corre- sponding to the purpose for which it is required, as per table below, when it is again plunged into water. Corresponding Temperature. A very pale straw 430' Lancets | Straw" 450' llazors \ Darker straw 470° Penknives | All kinds of wood tools. Yellow 490° Scissors { Screw taps. Brown yellow 500'' ) Hatchets, Chipping Chisels, Slightly tinged purple. 520' V Saws Purple 530° ) All kinds of percussive tools. Dark purple 550° ) o„_;„„„ Blue ... 57(^o f feprmgs. Dark blue 600° Soft for saws. To Temper by the Thermometer. Put the articles to be tempered into a vessel containing a suffi- cient quantity to cover them of oil or tallow; sand; or a mixture of 8 parts bismuth, 5 of lead, and 3 of tin, the whole to be brought up to, and kept up at the heat corresponding to the hardness required, by means of a suitable thermometer, till heated ciinally throughout; the articles are then withdrawn and plunged into cold watir. If no thermometer is available, it may be ob- served that oil or tallow begins to smoke at 430 ' or straw color, and that it takes fire on a light being presented, and goes out when the light is withdrawn, at 570° or blue. Case Hardening. Put the articles requiring to be hardened, after being finished but not j)olished, into an iron box in layers with animal carbon, that is, horns, hoofs, skins, or leath(;r, partly burned so as to be capable of being reduced to jjowder, taking can; tliat every part of the iron is completely surrounded; make tlie box tight with a lute of sand and clay "in equal parts, put the whole into the fire, and keep it at a light red lieat for half an hour to two liours, aceordiiig to the di])th of hardiiieil surface retpiin^d, then empty tlie contents of the; box into water, care being taken tliat any articles liable to buckle bo put in separately and carefully, end in first. Cast iron nny be case hardened as follows : Hring to a red heat, and roll it in a mixture of powdered prns- siate of potiisli. H'dtix'trr', and sul-ammoniac in equal i)arts, tlien l>buigc it into 11 balli containing 2 o/,. pru.ssiatu of potash, an I i oz. Halanimoniao p-ir gallmi of water. WEIGHT OF CASTINGS. 209 To find the Weight of any Casting. Width in J- in. X thickness in I in., or, vice versa, -f- 10 X length, ft. = wt. lbs. , cast iron. For instance : To find the weight of a casting 3} in. X H in. X 2 ft. 6 in. long. 13 X 9-i- 10 = 11.7 X 2.5 = 29.25 Ib.s. This rule is very useful, and can easilj' be remembered in the following form : Width in ] in. X thickness in J in. ; or, vice versa, cut off 1 figure for decimal, the resiilt is lbs. per foot of length. For wrought iron add 1-20 to the result ; for lead add ^ ; for brass add 1-7 ; for copper add 1-5. To FIND THE Weight from the Aeeas. Area, sq. ins. X length, ft. X 3 1-7 = wt. lbs. cast iron. Multiplier for cast iron 3. IfiG, or 3 1-7 " " wrought iron 3.312, "3^ " " leiid 4.854 " " brass 3.644 " " copper :i87 or, area sq. ins. X 10 = lbs. per yard for wrought iron. To FIND the W"eIGHT IN CwTS. Area, sq. ins X length, ft. -^31.9 = wt. cwts. cast iron. For wrought iron -^ 33.6. To compute the Weight or Cast ^Ietal by the Weight of THE Pattern, avhen the Pattern is of White Pine. Rttle. — Multiply the weight of the pattern in lbs. by the fol- lowing multiplier, and the product will give the weight of the casting. Iron, 14 ; brass, 15 ; lead, 22 ; tin, 14 , zinc, 13.5. Table of Alloys. AUojb hi^^■ing a density ffrentor than the Meiin of their Conaliluents. Gold and zinc. Gold and tin. Gold and bismuth. Gokland antimony Go'd and cobalt. Silver and zinc. Silver and lead. Silver and tin. Silver and bismuth Silver & antimony. Copper and zinc. Copper and tin. Cojiper &paUadium Copper & bismuth. Lead and antimony Platinum & molyb- denum, (ninth. Palladium and bis- Alloys having a density legs than the Mean ot their Constituents. Gold and silver. 'Told and iron. Gold and lead. Gold and copper. Gold and iridium. Gold and nickel. Silver and copper. Silver and lead. Iron and bismuth. Iron and antimony Iron and lead Tin and lead. Tin and palladium. Tin and antimony. Nickel and arsenic. Zinc and antimony 210 PRACTICAL MECHANICAL RECEIPTS. Alloys of Copper and Zinc, and Copper and Tin. Composition by Weight per cent 'S > 8667 Color. s"Hs — X X » Characteristic Tropertiea, &c. Copper rile red. 24.6 Malleable. 100.00 Zinc 6895 Bluish gray. 15.2 Brittle. 8-i.0-2- -lfi.98 8415 Yellowish red. 13.7 Bath metal. 7!).65- -iO.35 8448 (( i( 14.7 Dutch brass. 74.58- -25.42 8397 Palo yellow. 13 1 Rolled sheet brass. 6rt.l8- -33.82 8299 Full yellow. 12.5 British brass. 4'J.i7- -50.53 8230 11 " 1.9 White button metal Tin 7291 White. 2.7 84.29-1 f-15.71 8561 Ilcddish yellow 16.1 Gun-metal. 81.10- -18.9i) S459 I'ellowish red. 17.7 Gun-metal and bronze. 78.1)7- -21.03 8728 i( (( 13.6 Hard, mill brasses. 34.92- -65.08 8065 White. 1.4 Small bells. 15.17- -Hi.ys 7417 Very white. 3.1 Speculum metal. Files, tough. 1L82- -88.13 7472 (i (t 3.1 Note. — No simple binary alloy of copper and zinc, or of copper and tin, works iis pleasantly in turning, planing, or filing, as if combined with a small proportion of a third fusible metal; gen- erally lead is added to copper and zinc, and zinc to copper and tin. Alloys for Bronze. Professor Hoffman, of the Prussian artillery, lias made experi- ments with the view of obtaining a good statuary bronze, and recommends the alloys ranging between the two following ad- mixtures : 1st. To produce! the reddest l)ronze. 88.75 copper zinc (7 atoms copper, 1 atom zinc). 11.25 copper tin (3 atoms copper, 1 atom tin). 100.00 2d. To produce a cheap bronze, with a bright yellow color, al- most golden. 93.5 copper zinc (2 atoms copper, 1 atom zinc). 6.5 copper tin (3 atoms copper, 1 atom tin). 100.00 GllU'- Powdered chalk ailded to common glue strengthens it A g''ie which will resist the action of water is made by boiling 1 pound of glue in 2 (j>iarts of skimmed milk PRACTICAL MECHANICAL RECEIPTS. 211 To Joint LiCftd Pipes. —Widen out the end of one pipe with a taper wood drift, and scrape it clean inside ; scrape tho end of the other pipe outside a little tapered, and insert it in tho former; then solder it with common lead solder as before de- scribed; or if required to be strong, rub a little tallow over, and cover the joint with a ball of melted lead, holding a cloth (2 or 3 plies of greased bed-tick) on the under side; and smoothing over with it and the plumber's iron. To 2>oUsh Brass. — When the brass is made smooth by- turning or filing with a very fine file, it may be rubbed with a smooth fine grained stone, or with charcoal and water. When it is made quite smooth and free froui scratches, it may be polished with rotten stone and oil, alcohol, or spirits of turpentine. To clean Bi'ftss. — If there is any oily substance on the brass, boil it in a solution of potash or strong lye. Mix equal quantities of nitric and sulphuric acids in a stone or earthen vessel, let it stand a few hours, stirring it occasionally with a stick, then dip the brass in the solution, but take it out imme- diately and rinse it in soft water, and wipe it in sawdust till it is dry. To fill Soles ht Castings. — Lead, 9 i^arts; antimony, 2; and bismuth, 1: to be melted and poured in. Babbitt ilffef'fZ— Copper, 4 lbs.; regulus of antimony, 8 lbs. ; Banca tin, 88 lbs. To soften Iron or Steel.~\noint it all over with tallow; heat it in a charcoal fire; then let it cool. To restore Burnt Steel.— Bovax, 3 oz. ; sal-ammoniac, 8 oz. ; prussiate of potash, 3 oz. ; blue clay, 2 oz. ; resin, LV lbs.; water, 1 gill; alcohol, 1 gill. Put all on a fire, and simmer until it dries to a powder; then heat the steel and dip it into this pow- der and hammer it. Babbitt JMetal. — Block tin, 8 lbs. ; antimony, 2 lbs. ; copper, 1 J lbs. If the metal is too hard add a little lead. Composition to toughen Steel. — Resin, 2Jlbs. ; tallow, 2| lbs.; i^itch, IJ lbs. Melt together, and apjjly the steel while hot. Substitute for Borax. — Copperas, 2 oz. ; common salt, 5 oz. ; saltpetre, 1 oz. ; black oxide of manganese, 1 oz. ; prussiate of potash, li oz. Pulverize and mix with 3}, lbs. of welding sand: use same as borax. Tempering Liquids. — Salt, 4 oz. ; saltpetre, ^ oz. ; pul- verized alum, 1 oz. ; soft water, 1 gallon. Heat to a cherry red, but do not draw the temper. JLnother. — Saltpetre and alum, each 2 oz. ; sal-ammoniac, ^ oz. ; salt, li lbs.; soft water, two gallons. Heat to a cherry red and plunge in. 212 PRACTICAL MECHANICAL RECEIPTS. Case- Hardening for Iron. — Heat the iron to a bright cherry red, then roll it in a composition composed of equal parts of sal-ammoniac, saltpetre, and prussiato of jjotash; cover the iron thoroughly with this composition, and plunge it while hot into a bath composed of 2.\ oz. prussiate of potash, i^ oz. sal- ammoniac, and 1 gallon of Avater. To restore Surnf Steel. — Borax, 3 lbs.; sal-ammoniac, 1 lb. ; prussiate potash, ^ lb. ; resin, i lb. ; alcohol, 1 gill; soft water, 1 pint. Put into an iron pan ami hold over a slow fire until it comes to a slow boil and until the liquid matter evajiorates; be careful to stir it well from the bottom and let it boil slow. This receipt is very valuable, no matter how bad the steel is burned, it will restore and make it as durable as ever. To hlne Gun Sarrels.—AYiply nitric acid and let it eat into the iron a little ; then the latter will be covered with a thin film of oxide. Clean the barrel, oil, and burnish. Lininff So.ves with Babbitt Metal. — Heat the box hot enough to melt the metal; then smoke the shaft where the metal is to be poured in; this insures its coming out of the box readily after it is cold. After smoking the shaft put it into the box and l>ut putty around the ends, taking care not to press too hard, or the putty will be forced into the box; then heat your metal and pour in, letting it stand until cold; then drive out the shaft and it is complete. To estimate the Percentatje of Iron in Ores.—Fre- parc a crucible of refractory clay by pressing into it successive layers of moistened powdered charcoal until full and solid; clear out a cavity by removing the central portion. Take 200 grains of the powdered ore, and mix it with the same weight of dry slacked lime, and 50 grains charcoal ; if necessary a little carbonate of soda may be used with very refra(^tf)ry ores ; introduce this mix- ture into the crucible and lute it up. Expose the crucible to a moderate heat until the contents of the crucible are dry, then apply and maintain for half an hour the full heat of a blast fur- ■ nace. Then remove the crucible, tap it steadily on the edge of the fiiniaee, so as to bring the metallic portion of its contents together at the bottom ; and, when cool, break the crucible open. The iron will be found in a ch^an button at the bottom of tho slag. Clean tlie iron with a scratch brush, and weigh it. Its weight, divided by 2, will give the percentage of richness of tho ore untb'r cxuininatinn. Todititin pounds of brown sugar protected his boiler for two mouths ; another, that G pounds of corn .starch sirup had a similar effect. Another used moliiss&s with success, introducing a gallon at a time. Fattif Siiltxfuuces us Preventives. Ono writer used whale oil to jin vent incrustations, '2 or 3 gallims at a time. Others smear tlio inside of the boiler with various mixtures of a fatty character. Stearine, mixed with wood ashes, charcoal, and tar, hivs been recommendi.d; or tallow, with soap and charcoal diluted with oil or tar. or tillow and grajjliite. This plan cf)ul I not well be apjilii'l to a locomotive l)oiler witli its numerous tabus, even though il should prove effective in cylinder boilers. PRACTICAL MECHANICAL RECEIPTS. 215 To protect Iron from Rust. — A mastic or covering for this purpose, proposed by M. Zeni, is as follows: IVIix 80 parts pounded brick, passed through a silk sieve, with 2U parts lith- arge; the vrhole is then rubbed up by the muUer with linseed oil, so as to form a thick paint, which may be diluted with spirits of turpentine. Before it is applied the iron should be well cleaned. From an experience of two years upon locks exposed to the air, and wateresl daily with salt water, after being covered with two coats of this mastic, the good effects of it have been thoroughlj" proved. To jirevent the Decatj of Iron Rail inf/s.— 'Every one must have noticed the destructis-e combination of lead and iron, from railings being fixed in stone with the former metal. The reason for this is, that the oxygen of the atmosphere keeps up a galvanic action bet\v\-LU tiie two metals. This waste may be pre- vented by substituting zinc for lead, in which case the galvanic influence would be inverted; the whole of its action would fall on the zinc ; the one remaining uninjured, the other nearly so. Paint formed of the oxide of zinc, for the same reason preserves iron exposed to the atmosphere infinitely better than the ordinary jDaint composed of the oxide of lead. To clean Steel and Jroii.— Make 1 ounce soft soap and 2 ounces emery into a paste ; rub it on tlie article with wash- leather and it will have a brilliant polish. Kerosene oil will also clean steel. To convert Iron into Steel.— This is usually done by the process of cementation, producing what is termed blistered steel. At the bottom of a trough about 2 feet square and 14 feet long, usually formed of fire-clay, is placed a layer, rdjout 2 inches thick, of a cement composed of 10 parts charcoal and I part ashes and common salt ; upon this is laid a tier of thin iron bars about J inch apart ; between and over them, a layer of cement is spread, then a second row of bars, and so on, alternate- ly, until the trough is nearly full; lastly a layer of cement cover- ed with moist sand and a close cover of fire-tiles, so as to exclude the air. The trough is exposed to the heat of a coal fire, until a full red heat, about 2')00° Fahr., is obtained and kept up steadily for about 7 days. A hole is left in the end of the trough, to allow of a bar being drawn out for examination. When a bar, on being withdrawn an 1 broken, has ac(^nired a crystalline texture, the metal is allowed to cool down gradually, some days being allowed for this, and the charge, when cool, withdrawn from the trough. The bars will be found covered with large blisters, hence the name of the process, and increased about -^i^ in weight. The steel is now sufficiently good for files and coarser tools, but for finer instruments several varieties of finer steel are required. Steel made from Iron ,Srrrf;>.s\— Take iron scraps in small pieces, put 40 pounds in a crucible, with 8 ounces charcoal, and 4 ounces black oxide of manganese ; expose the whole 1 j hours to a high heat and run into moulds. 216 PRACTICAL MECHANICAL RKCEIPTS. To malic Sheaf S^ec?.— This is produced by cutting up bars of blistered steel, into lengths of 30 inches, and binding them in bundles of 8 or 9 by a ring of steel, a rod being fixed for a handle. These are brought to a welding heat, and welded together under a tilt hammer. The binding ring is then removed; and, after reheating, tin mass is forged solid, and ex- tended into a bar. In cases where this operation is repeated, the steel is called double-shear steel. To make Cast Sf re?.— Cast steel is the best variety for all fine cultiug tools. This is a mixture of scraps of different varieties of blistered steel, collected together in a good refractory clay crucible; upon this a cover is luted, and it is exposed to an intense heat in a blast furnace for 3 or 1 hours. The contents are then run into moulds. After being subjected to the blows of a tilt-hammer, the cast steel is ready for use. To keejt Polislied Iron Work brhfltt— Common resin melted with a little gallipoli oil and spirits of turpentine has been found to answer very well for preserving polislied iron work bright. The proportions should be such as to form a coating whudi will adhere firmly, not chip off, and yet admit of being easily detached by cautious scra]>ing. To take Proof -Impressions of Seals and Stamps. —For this purpose the very best sealing-wax is m.lted as usual by a flame, and carefully worked on the surface to which it is applied, until perfectly even; the stamp is then firmly and evenly pressed into it. The fiame of a spirit lamp is preferable, having no tendency to blacken the wax. A beautiful dead appearance is given to the impression by dusting the stamp before using it with a finely-powdered pigment of the same color as the wax ; thus, for vermilion sealing-wax, powdered vermilion, &c. To hliie Steel. -T\\o mode emidoyed in blueing steel is merely to subject it to heat. The dark blue is produced at a temperature of GOO', the full blu(! at r>0(r, and the blue at 550°. The steel must be finely polished on its surface, and then ex- posed to a uniform degree of heat. Accordingly, there arc throe ways of coloring: first, liy a flame producing no soot, as spirit of wine; secondly, by a hot plate of iron; and thirdly, by wood ashes. As a very regular degree of heat is necessary, wood ashes for fine work bear the preference. The work must be covered over with them, and canfutlv watched; when the color is siilfi- ciently heiglitened, the workis perfect. This color is occasion- ally tiiken off with a very dilute muriatic acid. To reiiiore Scale fnun Steel. --'^(•■.xhi may bo removed from steel articles by i)ickliug in water with a little stilphnria acid in it, and when the scale is loosened, brushing with sand and a stiff brush. To temper Spiral Sprhnjs. Ibat to a cherry red in n charcoiil firr, un.l liard.n in oil. To temper, blaze oflF the oil three times, the samo as for Hat springs. PRACTICAL MECHANICAL RECEIPTS. 217 Cautions on the use of Lead for Cisterns, tCc. — Ordinary water, wLicli abounds in mineral salts, may be safely kept in leaden cisterns ; but distilled and rain water, and water that contains scarcely any saline matter, speedily corrode, and dissolve a portion of lead, when kept in vessels of that metal. When, however, leaden cisterns have iron or zinc fastenings or braces, a galvanic action is stt up, the preservative power of saline matter ceases, and the water si^eedily becomes contami- nated Avith lead. Water containing free carbonic acid also acts on lead ; and this is the i-eason why the water of some sjirings, kept in leaden cisterns, or raised by leaden pumps, possesses unwholasome properties. Free carbonic acid is evolved during the fermentation or decay of vegetable matter, and hence the propriety of preventing the leaves of trees falling into water- cisterns formed of lead. To test the Richness of Lead Oi'es.— Lead ores, or galena, may be tested in different ways. The wet way is as fol- lows: Digest 100 grains of the ore in sufficient nitric acid diluted with a little water, apply heat to expel any excess of acid, and largelj' dilute the remainder with distilled water. Next add dilute hydrochloric acid, by drops, as long as it occasions a pre- cipitate, and filter the whole, after being moderately heated, upon a small paper filter. Treat the filtered liquid with a stream of suli^hureted hydrogen ; collect the black precipitate, wash it, and digest it in strong nitric acid; when entirely dissolved, pre- cii:)itate the lead with sulphuric acid dropped in it, evaporate the precipitate to dryness, the excess of sulphuric acid being ex- pelled by a rather strong heat applied toward the end. The dry mass should be M^ashed, dried, and exposed to slight ignition in a porcelain crucible. The resulting dry sulphate is equal to .G8 per cent, of its weight in lead. To anneal Steel. — For a small quantity. Heat the steel to a cherry red in a charcoal fire, then bury it in sawdiist, in an iron box, covering the sawdust with ashes. Let it stay until cold. For a larger quantity, and when it is required to be very soft, pack the steel with cast iron (lathe or planer) chips in an iron box, as follows: Having at least i or | inch in depth of chips in the bot- tom of the box, put in a laj'er of steel, then more chips to fill sjiaces between the steel, and also the ^ or J inch space between the sides of box and steel, then more steel ; and lastly, at least 1 inch in depth of chips, well I'ammed down on top of the steel. Heat to and keep at a red heat for from 2 to i hours. Do not disturb the box until cold. To straighten Hardened Steel.— To straighten a piece of steel already hardened and tempered, heat it lightly, not enough to draw the temj^er, and you may straighten it on an anvil with a hammer, if really not dead cold. It is best, how- ever, to straighten it between the centres of a lathe, if a turned article, or on a block of wood with a mallet. Warm, it jdelds readily to the blows of the mallet, but cold, it would break like glass. 10 21S PRACTICAL MECHANICAL RECEIPTS. To prevent the Corrosion of Copper and otlter 3rt:une(l, divided by 10, gives t!ie percentage of metallic lead in the sample of ore. To temper PielkS.—MUv working the steel carefully, pre- pare a bath of lea 1 heated to the boiling point, whicli will be indicated by a slight agitation of the surfiu^e. In it jjlaco the end of the pick to the dcjjth of \\ inches, until lieate. 1 he lead bath iicts merely as protection against the heat, which is almost always too great to temper welL PRACTICAL MECHANICAL RECEIPTS. 219 To hliie sin^ll Steel Articles. — Make a box of sheet iron, fill it with sand, and subject it to a great heat. The articles to be blued must be finished and well polished. Immerse; the arti- cles m the sand, keeping watch of them until they are of the right color, when they should be taken out and immersed in oil. To restore burnt Cast Steel.— Take IJ lbs. borax, k lb. sal-ammoniac, 4 lb. prussiate of potash, 1 oz. resin. Pound the above fine, add a gill each of water and a'cohol. Put in an iron kettle, and boil until it becomes a paste. Do not boil too long, or it will become hard on cooling. To temper I>riUs. — Heat the best steel to a cherry red, and hammer until nearly cold, forming the end into the requisite flattened shape, then heat it again to a cherry red, and plunge it into a lump of resin or into quicksilver. A solution of cyanide of potassium in rain-water is sometimes used for the tempering plunge-bath, but it is not as good as quicksilver or resin. To temper Gravers. — These may be tempered in the same way as drills ; or the red-hot instrument may be pressed into a piece of lead, in which a hole about \ an inch deep has been cut to receive the graver ; the lead melting around and inclosing it will give it an excellent temper. To temper Old Files. — Grind out the cuttings on one side, until a bright surface is obtained; then damp the surface with a little oil, and lay the file on a piece of red-hot iron, bright side upward. In about a minute the bright surface will begin to turn yellow, and when the yellow has deej)ened to about the color of straw, plunge in cold water. To maJxe Polished Steel Stratv Color or Slue.— The surface of polished steel acquires a pale straw color at 460° Fahr., and a uniform deep blue at 580"^ Fahr. liath for harden ittf/ PieJxS. — Take 2 gallons rain-water, I ounce corrosive sublimate, 1 of sal-ammoniac, 1 of saltpetre, II pints rock salt. The picks shouhl be heated to a cherry red, an 1 cooled in the bath. The salt gives hardness, and the other ingredients toughness to the steel ; and they will not break, if they are left without drawing the temper. Composition for temperinff Cast- Steel Mill Pieks. To .S gallons of water, add 3 ounces each nitric acid, spirits of hartshorn, sulphate of zinc, sal-ammoniac, and alum; 6 ounces salt, with a double handful of hoof-parings; the steel to be heat- ed a dark cherry red. It must be kept corked tight to prevent evaporation. Tempering Steel — Mr. N. P. Ames, late of Chicopee, Mass., after expending mvich time and money in experiments, found that the most successful means of tempering swords and cirtlasses that would stand the United States Government test, was by heating in a charcoal fire, hardening in pure spring water, and drawing the temper in charcoal flame. 220 PRACTICAL MECHANICAL RECEIPTS. Engraving 3Hxttire for Writing on Sfc«r —Sulphate of copper, 1 ounce; sal-ammoniac, ^ ounce; pulverize separately, adding a little vermilion to color" it, and mix with \\ ounces vinegar. Eub the steel with soft soap and write with a clean hard pen, without a slit, dipped in the mixture. To nwhe Edge-Tools from Cast Steel and Iron.— This method consists in fixing a clean piece of wrought iron, brought to a welding heat, in the centre of a mould, and then pouring in melted steel, so as entirely to envelop the iron; and then forging the mass into the shape required. Cement for fixing Metal to Leather.— ^Yash the metal in hot gelatine, steep the leather in hot gall-nut infusion, and unite while hot. Cenhent for Gai^ Iietort.s.—\ new cement, especially adapted to Vae retorts of gas-works, is very warmly recommend- ed in a German gas-light journal. It consists of fincly-i^owdered barytes and a soluble watei'-glass ; or the barytes and a solution of borax. The joints are to be coated several times with this cement, by means of a brush. The addition of two-thirds of a part of clay improves the cement, and the retorts will then stand a red heat very well. Instead of the water-glass, a solution of borax may bo used, or even finely powdered white glass. Cement for Cloth, Leather, or Belting.— Tnke ale, 1 pint ; best Ilussia isinglass, 2 oui^ccs ; jnit them into a common glue kettle and boil uutil the isinglass is dissolved ; then add 4 ounces best glue, and dissolve it witli the other; then slowly add IJ ounces boiled linseed oil, stirring all the time while adding and until well mixed. When cold it will resemble india-rubber. To use this, dissolve what is needed in a suitable quantity of ale to the consistence of thick glue. It is applicable for leather, for harness, bands for machinery, cloth belts for cracker machines for bakers, Ac, Ac. If for leather, shave off as if for sewing, apply the cement with a brush while hot, laying a weight to keep each joint firmly for G to 10 liours, or over night. Cement for Lit/ther Jielting.—Tiike of common glue an I American isinglass, ecpial parts ; place them in a glue-pot anrussiat(: app-itrs to be deeomi)osed and dissipated, plunge tho articl(! into cold water. Wlien the j)rocess of case-hardiiiing has been well (conducted, the surface of tlio metal j)roves sullieiently liard to resist a tile;. Tlie last two ])lans are a great imprir nne(|Uiil expansion by heat. In a recent issue of tlie journal of " A2)pli('d Chemistry," a new alloy is given, for which the inventor claims an expansion by heat so nearly similar to that of iron as to allow of a vmiou be- tween them, which, for all jiractical purposes, is permanent. This consists of a mixture of 79 parts copper, 15 parts zinc, and 6 jiarts tin. To harden Urass.— Bxaas is tempered or hardened by roll- ing or hammering; conseq\iently, if any object is to be made of tempered brass, the hardening must be done before working it into the rc<]uired shape. To soften lirass. — Heat it to a cherry red, and plunge it into water. To eorer lirass with heautiful Lustre Colors.— Dissolve 1 ounce cream of tartar in I quart of boiling water; then add .', ounce protochloride of tin dissolved in 4 ounces cold water. Next" heat the whole to boiling, and dec.int the clear solution from a trilling precipitate, and pour, under continual stirring, into u solution of 3 ounces hyposulphate of so.la in \ pint water, then heat again to boiling ami filter from the separated sulphur. This s ilution i)rol(> n.', pounds cojiper; when fused add ^ pound /ine; these m<'tais will combine, forming an alloy of a reddish color, but pos.sessing more lustre than copper, Bnd also great«:r durability. PRACTICAL MECHANICAL RECEIPTS. 227 IJlilte Tombac. — "Wlien copper is combined with arsenic, by melting them together in a close crucible, and covering the surliice with common salt to prevent oxidation, a white brittle alloy is formed. French Hell-J^Tetal. — The metal used in France for hand- bells, clock-bells, etc , is made of £5 to 60 parts copper, 3 J to 40 parts tin, and 10 to 15 parts zinc. Alloy of Niclxel and Copper. — A mixture of 1 part nickel and 2 parts cojiper produces a grayish-white metal, tenacious, ductile, and moderately fusible. To put a Black Finish on Brass Instruments. — Make a strong solution of nitrate of silver in one dish, and of nitrate of copper in another. Mix the two together, and plunge the brass in it. Now heat the brass evenly till the required de- gree of dead blackness is obtained. This is the method of pro- ducing the beaiitiful dead black so much admired in optical instruments, and which was so long kept a secret by the French. Speculum Metal for Telescopes.— Meli 7 pounds of cop- per, and when fused add 3 pounds zinc an 1 4 j^ounds tin. These metals will combine to form a beautifv;l alloy of great lustre, and of a light 5'ellow color, fitted to be made into specula for tele- scopes. Mr. Mudge used only copper and grain tin, in the pro- portion of 2 pounds of the former to 14^- ounces of the latter. Phosphor Bronzes. — A great advance has lately been made in the consti-ucti(in of bronTies, by the addition of a small per- centage of phosphorus, although the precise function of this substance has not been hitherto well understood. According to Levi and Kunzel, however, one cause of the inferiority in bronze consists in the constant presence of traces of tin in the state of an oxide, wliich acts mechanically by separating the molecules of the alloy, thus interposing a substance which in itself has no tenacity. The addition of phosjahorus reduces this oxide, and renders the alloy much more perfect, imMroving its color, its tenacity, and all its physical properties. The grain of its frac- ture resembles more that of steel, its elasticity is miich augment- ed, and its resistance to pressure sometimes more than doubled. Its durability is greater, and when melted it is of greater fluid- ity, and fills the mould in its finest details. To clean Bronze. — It was observed in Berlin that those parts of a bronze statue which were much handled by the public retained a good surface, and this led to the conclusion that ftxt had something to do with it. An experiment was therefore tried for some years with four bronzes. One, says our authority- Chambers' Journal — was coated every day with oil, and wiped "with a cloth ; another Avas washed every day with water ; the third was similarly washed, but was oiled twice a year; and the foiirth was left untoiached. The first looked beautifully; the third, which had been oiled twice a year, was passable; the sec- ond looked dead; and the fourth was dull and black. 228 PRACTICAL MECHANICAL RECEIPTS. Gongs tind Cf/mhals. — The secret metlunl employed by the Chinese for working the hard brittle bronze used ibr making gongs and cymbals, seems to be solved by the fact that the bronze of which these instruments are made, consisting of copper alloyed with about 2U per cent, of tin, und almost as brittle as glass at orlinary temperatures, becomes as malleable as soft iron, if worked at a tluU red heat. This discovery was recently made in Paris by MM. Julien and Champion, the result of ex- periments at the Paris Mint. F'onfoincinoi'Cdii's Uronzes. — This is a kind of bronze known as IVnitainemoroau's bronze, in which zinc predominates. It is said to answer well for chill moulding, that is, for pouring in metal moulds, by which method it is rendennl very homoge- neous The crystalline nature of the zinc is entirely changed by thar(s <-a(lmium, 4 tin, 8 lend, and ];"» bismuth. It has a brilliant metalli(r lustre, and does not farnisli readily. yiu/ld AJloif ofSoflhnn and I'otosshnn. — If 4 ])arts Hodiuin are mixed with 2.\ i>i>tassiuiii, llie alloy will have exactly tlie api)earanee ami consistency of mercury, remaining liquid at tlio ordinary temperuturo of the air. PRACTICAL MECHANICAL RECEIPTS. 'I'Z9 Fusihle Alloys. — Bismuth, 8 parts; lead, 5 parts; tin, 3 parts; melt together. Melts below iil2° Fahr. Or: Bismuth, 2 parts; lead, 5 parts; tin, 3 parts. Melts in boiling water. Or: Lead, 3 parts; tin, 2 parts; bismuth, 5 parts; mix. Melts at 197" Fahr. The above are used to make toy-spoons, to surprise chil- dren by their melting in hot tea or coffee; and to form pencils for writing on asses' skin, or paper prepared by rubbing burnt hartshorn into it. The last may be employed as an anatomical injection, by adding (after removing it from the fire) 1 part quick- silver (warm). Liquid at 172^ solid at 140'^ Fahr. Engestvooni Tufania.— Melt together 4 parts copper, 8 parts regulus of antimony, and 1 part bismuth. When added to . 100 parts of tin, this compound will be ready for use. TJte most Fusible Alloij.— There is an alloy of bismuth, tin, and lead, which, from its very low melting point, is called fusible metal. Dr. Von Hauer has found, however, that the addi- tion of cadmium to the alloys of the above-mentioned metals re- duces their melting point still lower. An alloy of 4 volumes cadmium, with 5 volumes each tin, lead, and bismuth, is quite liquid at 150"^ Fahr. In parts by weight, the above would be 22i parts cadmium, 517.V lead, 295 tin, and 1050 bismuth. An alloy of 3 volumes of cadmium, with 1 each of tin, lead, and bismuth, fuses at 153.}° Fahr., and an alloy of 1 equivalent of cadmium with 2 equivalents each of these three other metals, at 155J°, which is also the fusing point of an alloy of 1 part each of all the four metals. Dr. Von Ilauer made these alloys by fusing their ingre- dients in a covered porcelain crucible at the lowest practicable temperature. They all become pasty at lower temperatures than those given above; the temperatures quoted are those at which the alloys are perfectly fluid. It should be added that, unfor- tunately, all these alloys very rapidly oxidize when placed in water. Brass Solder for hrazing Iron or Steel.— ThiD. plates of brass are to be melted between the pieces that are to be joined. If the work be very fine — as when two leaves of a broken saw are to be brazed together-cover it with pulvei'ized borax, dissolved in water, that it may incorporate with some brass powder which is added to it; the piece must be then exposed to the fire with- out touching the coals, and heated till the brass is seen to run. To tin Iron for Soldering, <€r.— Drop zinc shavings into muriatic (hydrochloric) acid, until it will dissolve no more; then add \ its bulk of soft water. Iron, however rusty, will be cleansed by this solution, and receive from it a sixfficient coating of zinc for solder to adhere to. To solder ffrat/ Cast Iron. — First dip the castings in alco- hol, after which, sprinkle muriate of ammonia (sal-ammoniac) over the surface to be soldered. Then hold the casting over a charcoal fire till the sal-ammoniac begins to smoke, then dip it into melted tin (not snider). This prepares the metal for solder- ing, which can then be done in the ordinary way. 230 PRACTICAL MECHANICAL RECEIPTS. To solder Ferrules for Tool II(i miles.— Hiike the fer- rule, l;ip round the jointing' a small piece of brass wire, then just wet the ferrule, scatter ground borax on the joining, put it on the end of a wire, and hold it in the fire till the brass fuses. It ■will fill up the joining, and form a perfect solder. It may after- ward be turned in the lathe. Solder for Iron. —Fuse together G7 parts copper and 33 parts zinc. Or: GO parts copper and i) parts zinc. Hard Solder for Copper or Brass.— I&ke 13 parts co^jper and 1 part zinc. Or: 7 copper, 3 zinc, and 2 tin. Solder for Brass iti Gene rrop.>i.— Melt the solder and pour it in a steady stream of about J inch in diameter, from a height of 2 or 3 inches, into cold water; taking care that the solder, at the time of pouring, is no hotter than is just necessary for fluidity. Alum in il m Solder — Mouray employs five different solders, being different proportions of zinc, copper, and aluminum. The copper is melted first, the aluminum is then added in 3 or 4 por- tions ; when the whole is melted, it is stirred with an iron rod. The crucible is then withdrawn from the fire, the zinc gradually stir- red into the mass, and tlie whole poured into ingot-shai)ed moulds, previously wii)ed out with benzine. The parts given in the following proportions are by weight. 1. — 80 parts zinc, 8 parts copper, 12 jiarts aluminum. 2.-85 " " 6 " 3.-88 " " 5 " " 4. _90 " " 4 " " 5.-94 " " 2 " " To solder Ala jni num. —The. selection of either of the above solders depen turpentine l)last lamj) is empli)yed. The more and oftener the solder is sjiread over tho surface, tho better it is. Aluminum Sohhr.-M soft solder is fused with one-half, one-ti>uitli, or (nie-eighth of its W(aglit of ziiu; amalgam (to bo made by dissolving zinc in juereury), a more or less hard and easily fusilde solder is obtained, wliich 7iiay lie used to solder nluniinum to itself or to other metals. Wcldinij (JinniKt^Hion.—VvLHQ borax M'ith 1-16 its weight of Bal-aniinoniac; cool, ])ulverizo, and mix with an e(|ual w<>iglit of (piiekliiue, wlien it is to l)o Kprinkler and 1 part corrosive sublimate. This preserves it from decay, and renders wood tou"h and more difficult to split. ° Tojtreserre and harden f food.— 'Wood steeped in a so- lution of copjieras becomes harder and more indestructible. German lleceipt fgH and ])lanks split at fh(^ ends bcejiusr tlic (■xi)osi(l surface dries fiLstcr than tlie insirle. Saturate muriatic, acid witli Jim,., and a])ply like whitewasli to the ends. The (^Idoride of cah-ium form- ewing the wood to dry and shrink more uniformly. PRACTICAL MECHANICAL RECEIPTS. 235 To petrify Wooden Objects.— Take equal quantities of gem-salt, rock-alum, white vinegar, chalk, and pebbles, powdered. Mix all these ingredients; ebullition will ensue. After it has ceased, throw some wooden objects into this liquid, and let them soak for 4 or 5 days, at the end of which time they will be trans- formed into petrifactions. To preserve Wood under Water.— V^'oo A impregnated with creosote oil has been found to resist effectually the ravages of the teredo worm; this worm being the cause of decay by honey- combing the entire substance of the wood. In G ermany chloride of zinc is used for this purpose, the timber being placed in boil- ers, partly exhausted of air, and the vapor of chlorine thus driven into it. These remedies are recommended by a commit- tee of practical experts, appointed by the Academy of Sciences in Holland, to ascertain the best means for preserving timber under water. Preservation of TFoorf.— Armand Muller has instituted some interesting experiments on this siibject, and arrives at the conclusion that the phosphate of baryta, formed by the mutual decomposition of phosphate of soda and chloride of barium, in the pores of the wood, is one of the best preservative agents avail- able to chemists. Soak the wood 5 days in a 7 per cent, solution of phosphate of soda, and, after drying, suspend in a 13 per cent, solution of chloride of barium for 7 days. It is believed that /wood thus prepared will withstand the action of moisture better than with any other preparation. The chief obstacle to the use *of such chemicals is in their cost. To coat Copper Plates with Brass.— 'E.^vose the plates, heated sufdciently, to the fumes of zinc. Zinc boils and is vaporized by heating it to a white heat. To coat the Inside of Copper Vessels with Brass. —Dissolve 1 part zinc amalgam in 2 parts muriatic acid ; add 1 part argol (crude tartar), and add sufficient water to fill the ves- sel ; then boil it in the vessel. « Graeger's Process for covering Iron atul Steel tvitli Copper without a Battery.— Ihe objects are first well cleaned, and then painted over with a sohition of proto- chloride of tin, and immediately afterward with an ammoniacal solution of sulphate of copper. The layer of copper thus pro- duced adheres so firmly to the iron or steel, that the different objects can be rubbed and polished with fine chalk without in- juring the deposit. The tin solution is prepared with 1 part crystallized chloride of tin, 2 parts water, and 2 parts hydro- chloric acid. The copper solution, with 1 part sulphate of cop- l^er, IG parts water, adding ammonia sufficient to redissolve the precipitate first thrown down by it. Zinc and galvanized iron can be treated, according to Bocttger, directly by the copper soliation, without using the tin salt. The above process may be found useful by gilders, and for various ornamental purposes. 238 PRACTICAL MECHANICAL RECEIPTS. To deposit Copper upon Cast Iron.— The pieces of cast iron are first placed in a bath male of 50 parts hytlro- cliloric acid, Ri)ecific gravit}' 1.105, and 1 part nitric acid ; next, in a second batli, composed of 10 parts nitric acid, 10 parts of chloride of copper, dissolved in 80 parts of the same hydro- chloric acid as just alhided to. The objects are rnbbed with a woolen rag and a soft brush, next washed with water, and again immersed iiiitil the desired thickness of copper is dcjiosited. When it is desired to give the a^jpearance of bronze, the copper surface is rubbed with a mixture of 4 parts sal-ammoniac and 1 part each oxalic and acetic acids dissolved in 30 parts water. IFeil's I*rocess for coating Iron icifh Copper. — This process yields a coating of copper of great brightness and strong cohesion. The object, whether of cast or wrought iron, is freed from rust by immersion for from 5 to 10 minutes in water containing 2 per cent, of muriatic acid, and subsequent scrubbing for \ hour with a wire brusli and sand, then washin'^ in water until all traces of acid are removed. It is then covered with zinc wire in spiral turns of about 6 inches from each other, which also s.Tves as a means of suspension. The bath consists of a solution of 8 parts caustic soda in 1 parts water, of which 11 quarts are mixed with 50 ounces Eoclielle salts and 1 J.\ ounces sulphate of copper, making a liquid of a density eipial to 19° Baiime. It retains its activity as long as the copper is kept re- placed, and deposition from it i)roceeds with great regularity. 'Ihe material of the vessel is best when made of wood, lined with gutta-percha, and covered with a wooden lid. When the coating is of sulHcieut thickness, the object is removed from the bath, first washed with water sliglitly acidifird with sulpliuric acid, and then witli i)ure water until the disappearance of all traces of acid ; after this it passes into a drying-room heated to 132° Fahr. The bronzing, when required, is obtained by a bath of sulphide of sodium, or by means of the same bath as above, somewhat modified, tliat is, by increasing the proi)orti(m of cop- l)er to a threefold, in which case the bath no longer deposits coi)j)er, but, to all appearances, bronze. l?y reducing the points of contact between the iron and wire, though retaining tlio spiral turns at uniform distances, the deposit gradually assumes a number of colors in the following series, viz.: orange, silver- white, pale yellow, golden yellow, carmine, green, brown, and dark bronze. As soon as the desired color is attaine 1, the object is washe 1 in warm water, and again dried at 132 '. Between each subsequent change of color is an interval of about 5 minutes. The reaction is more decided when the alkaline reaction of fho bath is stronger. For indoor work or ornaments the time of im- mersion may vary from 3 to 72 hours ; for outdoor objects a mueii longer time would Ije necessary. To tin a Cojtpcr I'cssel. — Boil the copper vessel with a solution of stannat<; of polassa mixed with tin borings, or Ixiil witli tin tilings .iml caustic alkali or cream of tartar. In a few minules a layer of pure tin v.ill bo firmly attached. PRACTICAL MECHANICAL RECEIPTS. 237 To tin Iron Pots and other Domestic Articles. — The articles are cleaned with sand, and. if necessary, with acid, and put then in a bath, prepared with 1 ounce cream of tartar, i ounce tin salt (protochloride of tin), 10 quarts water. This bath must be kept at a temperature of 190'^ Fahr , in a stone- ware or wooden tank. Bits of metallic zinc are put into and between the different pieces. When the coat of tin is considered thick enough, the articles are taken out of the fluid, washed with water, and dried. To till hy the Moist Way. — Make a solution of 1 part protochloride of tin in 10 parts water, to which add a solution of 2 parts of caustic soda in 20 j^arts water ; the mixture bo- comes turbid, but this does not affect the tinning operation, which is effected by heating the objects to be tinned in this fluid, care being taken, at the same time, to place in the liquid a piece of perforated block tin plate, and to stir up the fluid during the tinning with a rod of zinc. To tin Iron without the Aid of Heat— 'lo 105 quarts water are added 6| pounds rye meal ; this mixture is boiled for 30 minutes, and next filtered through cloth ; to the clear but thickish liquid are added 2 !3 pounds pyrophosphate of soda, 37J pounds protochloride of tin in crystals (so-called tin salt), 147^ poiinds neutral i^rotochloride of tin, 3.V to 4 ounces sul- phuric acid ; this li(|uid is placed in well-made wooden troiighs, and serves more especially for the tinning of iron and steel wire (previously polished) for the use of carding machines. When, instead of the two salts of tin just named, cyanide of silver and cyanide of potassium are taken, the iron is perfectly silvered. To cleanse Iron for Tinninr/. — The metal must be cleansed by immersion in an acid solution ; for new metal, this solution should be sulphuric acid and water, but for old metal, muriatic acid and water ; next scour with sand, and cleanse well with water. To tin Iron. — First cleanse as above, then heat the article just hot enough to melt the tin, rub the surface over with a piece of sal-ammoniac, and sprinkle some of the sal-ammoniac m powder over it ; then apply the tin and wipe it over evenly with a piece of tow. Cold Tinning. — Eub pure tinfoil and quicksilver together until the amalgam becomes soft and fusible, clean the surface to be tinned with spirits of salt (hydrochloric acid), and, while moist, rub the amalgam on, and then evaporate the quicksilver by heat. To tin Cast Copper or .Brass.— Make a saturated solu- tion of oxide of tin (tin putty), in potash lye; add to the solution some tin filings or shavings; make it as hot as possible ; then introduce the brass or copper and it will bo tinned in a few seconds. 238 PRACTICAL MECHANICAL RECEIPTS. Sfolhd'y. tnctUod of thiiihuj Copper, Brass, and Iron hi the Coltf, and irifhonf Apparatus. The ob- ject to be coated with tin must be entirely free tVoni oxide or rust. It must be carefully cleaned, and cave b(^ taken that no prease spots are left ; it makes no ditferenee whethi>r the object be cleaned mechanically or chemically. Two ])roparations are requisite for the purpose of tinning Zinc powder — the best is that prepared artificially by melting zinc and ])ouring it into an iron mortar. It can be (iasily pulverized immediately after solidi- fication ; it should be about as fine as writing sand. A solution of protochloride of tin, containing 5 to 10 per ci'nt., to which as much pulverized cream of tartar must be added as will go on the jioint of a knife. The object to be tinned is moistened with the tin solution, after winch it is rubbed hard with the zinc powder. The tinning appears at once. The tin salt is decomposed by the zinc, metal- lic tin being deposited. When the object tinned is polished brass or copper, it appears as beautiful as if silvcireil, and retains its lustre for a long time. This mrthod may be used in a labora- tory to preserve iron, steel, and copper api)aratus from rust ; and would become of great importance if the tinning could be made as thick as in the dry way, but this has not as yet been accom- plished. To tin Copper Tiiltes. — W. WoUweber i-ccommends for Ktill-worras cojjper tubes tinned inside in tlie following manner : To a solution of Rochdle salts a solution of salts of tin is added; a prociijitate of stannous tartrate is Ibrmed, whicli is washed and then dissolv(!d in caustic lye. The co])per tube, which has first been rinsed with sulphuric acid and then washed, is then filled with the alkaline solution, warmed a little, and touched with a tin rod, which causes the deposition of a coat of metallic tin. T > tin a tr!>rn. Copper Kettle. —A thick coating may be obtained by preparing a tinning solution of zinc dissolved in muriatic acid, making the solution as thick or heavily charged witli zinc as possil)le, adding a litth; sal-ammoniac. Ch'an the inside f)f the Jci'ttle, place it in a charcoal fir(! until a ])iece of blncdc tin placed inside; melts, then rub the melted tin, with some of the tinning solution, (juickly on tlui cyment of a slight degree of friction with a resinous or v.axy varnish, to bring out the wavy appearance characteristic of moire, which is also singularly enhanced by dropping a few iron nails into the bath. French lii'int liot water ; then add 2 ounces nitrate of copper, dissolved in i pint water; mix well, ami apjdy it rcjieatedly to the article, ]ilac.'d in a damp situation, by jucans of a brush moistened therewith. This produces a very antiart sulphate of iron, and 1 jtart siiljiliate of (;()])|)(r, in 2 ' ])arls watt-r ; afterward with a solution of 1 jtarts verdigris in 11 of distilled vinegar; leave for an hour to dry, and then polish with a soft brush and crocus. PRACTICAL MECHANICAL RECEIPTS. 241 To bronze Iron Castings.— Iron castings may be bronz- ed by thorough cleaning and subsequent immersion in a solu- tion of sulphate of cojiper, when they acquire a coat of the latter metal. They must be then washed in water. Surface Bronzing.— This term is applied to the proces? of impiuiing to the surfaces of figures of wood, plaster of Paris, &c., a metallic appearauce. This is done by first giving them a coat of oil or size varnish, and when this is nearly dry, apjilying with a dabber of cottoa or a camel-hair pencil, any of the metallic bronze powders ; or the powder may be placed in a little bag of musliu, and dusted over the surface, and afterward finished off with a wad of linen. The surface must be afterward varnished. Beautiful lied Bronze Powder.— ^li^ together sul- phate of copper, 100 ^larts ; carbonate of soda, GO parts ; apply heat until they unite into a mass, then cool, powder, and a'l'd copper filings, 15 parts; well mix, and keep them at a white heat for 20 minutes, then cool, powder, wash thoroughly with water, and di-y. Gold-Colored Bronze J*o«YZ^r.— Verdigris, Bounces; tutty powder, 4 ounces; borax and nitre, each 2 ounces; bichlo- ride of mercury, \ ounce ; make them into a paste with oil, and fuse them together. Used in japanning as a gold color. Or: grind Dutch foil or i^ure gold leaf to an impalpable powder. Bright Yelloiv Dye for TFoort.— To every gallon of water necessary to cover the veneers, add 1 pound French berries ; boil the veneers till the color has penetrated through; add some brightening liquid (see next receipt) to the infusion of the French berries, and let the veneers remain for 2 or 3 hours, and the color will be very bright. Liquid forlfriffhteninff and setting Colors.— To e^erj pint of strong aquafortis, add 1 ounce grain tin, and a piece of sal-ammoniac the size of a walnut; set it by to dissolve, shake the bottle round with the cork out, from time to time: in the course of 2 or 3 days it will be fit for use. This will be found an admirable liquid to add to any color, as it not only brightens it, but renders it less likely to fade from exposure to the air. Fine Blue Bye for Wood.— Into a clean glass bottle put 1 pound oil of vitriol, and 4 ounces best indigo pounded in a mortar (take care to set the bottle in a basin or earthen glazed pan, as it will effervesce*, put the veneers into a copper or stone trough ; fill it rather more than -J with water, and add as much of the vitriol and indigo (stirring it about) as will make a fine blue, which you may know by trying it with a jjiece of white paper or wood ; let the veneers remain till the dye has struck through. The color will be much improved if the solution of indigo in vitriol be kept a few weeks before using it. The color will also strike better if the veneers be boiled in plain water till completely soaked through, and left for a few hours to dry par- tially, previous to immersing them in the dye. 11 242 PRACTICAL MECHANICAL nnCKIPTS. Uriffht Green Dye for Wood.— Proceed as in either of the previous receiijts to procUace a yellmv; Lut instead of adding aquafortis or the brightening liquid, add as much vitriolated in- digo as will produce the desired color. Jiriffht lied Dye for Wood. — To 2 pounds genuine Brazil dust add 4 gallons water; put in as many veneers as the liquor •will cover ; boil them for 3 hours, then add 2 ounces alum and 2 ounces aquafortis, and keep it lukewarm until it has struck through. lied Dye for Wood. — To every pound of logwood chips add 'A gallons of water; put in the veneers, and boil as in the last; then add a sufficient quantity of the brightening liquid, tiU the color is of a satisfactory tint; heep the whole as warm as you can bear your finger in it, till the color has sufficiently penetrated. The logwood chips should be picked from all foreign substances with which it generally abounds, as bark, dirt, A:c. ; and it is always best when fresh cut, which may be known by its appear- ing of a bright red color; for if stale, it will look brown, and not yield so much coloring matter. Jtose-eolored Dye for If'ood. — Monier produces a fine pink or rose-color on wood of cellulose, especially that of the ivory nut, by immersing it first in a solution of iodide of potas- sium, 1} ounces jier pint of water, in which it remains for sevi-ral hours, when it is placed in a bath of corrosive sublimate, 135 grains to the pint. When properly dyed it is washed and var- nished over. We should think that less poisonous materials might be found to answer the same purpose. Drif/ht Purjde Dye for Wood. — Boil 2 pounds logwood, either in chips or powder, in 4 gallons water, with the veneers; after boiling till the color is well struck in, add by degrees vit- riolated indigo till the purple is of the shade reijuircd, whitdi may be known by trying it with a piece of jiaper; let it then boil for 1 hour, and keeji the licjuid in a milk-warm state till the color has penetrated the veneer. This method, when properly managed. Mill produce a brilliant purple. Yellow Jlnisa, for Turning. — (Common article.") — Copper, 20 lbs. ; zinc, 10 lbs. ; lead, from 1 to 5 ozs. Put in the iLoud last before pouring off. Jfrf? J?i7/s.s, FOBTuRNiNa. — Copper, 24 Ibs. ; zinc, 5 lbs. ; lead, 8 o/.s. But in the lead last before i)ouring off. Jted Jiross, for Tuknino. — Copper, 1(!0 lbs.; zinc, 50 Ib.s. ; lead, 10 lbs. ; antimony, '14 oz.s. Atntther ISrfi.Hs, for Turning. — Copper, 32 lbs. zinc, 10 lbs; lead, 1 lb. Jiesf. lieil Jii'ti.ss, i-ou Kink Castings. — Copjier, 24 lbs.; zinc, 5 lbs. ; bismuth, 1 oz. Put in the bismutti last before pour- ing off. PKACTICAL MECHANICAL RECEIPTS. 243 Bronze Metal. — Copper, 7 lbs. ; zinc, 3 lbs. ; tin, 2 lbs. Or: Copper, 1 lb.; zinc, 12 lbs.; tin, 8 lbs. JSell 3Tefal, for laege Bells. — Copper, 100 lbs.; tin, from 20 to 25 lbs. Hell 3£efctl, fob shall Bells. — Copper, 3 lbs; tin, 1 lb. Cock 3Ietal. — Copper, 20 lbs.; lead, 8 lbs.; litharge, 1 oz, ; antimony, 3 ozs. Hardening for Britannia. — (To be mixed separately from the other ingredients. ) — Copper, 2 lbs. ; tin, 1 lb. Britannia Metal, 1st Quality. — Tin, 150 lbs. ; copper, 3 lbs. ; antimony, 10 lbs. 2d Quality. — Tin, 140 lbs. ; copper, 3 lbs. ; antimony, 9 lbs. Fob Casting. — Tin, 210 lbs. ; copper, 4 lbs. ; antimony, 12 lbs. Foe SpiK>rtXG. — Tin, 100 lbs. ; Britannia hardening, 4 lbs. ; antimony, 4 lbs. Fob Registers. — Tin, 100 lbs.; hardening, 8 lbs.; antimony, 8 lbs. Foe Spouts. — Tin, 140 lbs.; copper, 3 lbs.; antimony, 6 lbs. Fob Spoons. — Tin, 100 lbs. ; hardening, 5 lbs. ; antimony, 10 lbs. Fob Handles. — Tin, 140 lbs. ; copper, 2 lbs. ; antimony, 5 lbs. Foe Lamps, Pillabs, and Spouts. — Tin, 300 lbs. ; copper, 4 lbs. ; antimony, 15 lbs. Casting. — Tin, 100 lbs.; hardening, 5 lbs.; antimony, 5 lbs. lAning MetaJ, fob Boxes of Railboad Cabs. — Mix tin, 24 lbs. ; copper, 4 lbs. ; antimonv, 8 lbs. (for a hardening) ; then add tin, 72 lbs. Fine Silver-colored Metal. — Tin, 100 lbs. ; antimony, 8 lbs. ; copper, 4 lbs. ; bismuth, 1 lb. German Silver, 1st Qualitt fob Casting. — Copper, 50 lbs, ; zinc, 25 lbs. ; nickel, 25 lbs. 2d Quality fob Casting. — Copper, 50 lbs.; zinc, 20 lbs.; nickel (best pulverized;, 10 lbs. Foe Rolling.— Copper, 60 lbs.; zinc, 20 lbs. ; nickel, 25 lbs. Fob Bells and othee Castings. —Copper, 60 lbs.; zinc, 20 lbs. ; nickel, 20 lbs. ; lead, 3 lbs. ; iron (that of tin-plate being best), 2 lbs. Imitation of Silver. — Tin, 3 ozs.; copper, 4 lbs. Hard White ^fetal.— Sheet brass, 32 ozs.; lead, 2 ozs.; tin, 2 ozs. ; zinc, 1 oz. Tombac.— Copper, 16 lbs.: tin, 1 lb.; zinc, 1 lb. Jted Tombac.— Co-pper, 10 Ib.s. ; zinc, 1 lb. 244 PRACTICAL MECHANICAL RECEIPTS. PincJibecJc. — Copper, 5 lbs. ; zinc, 1 lb. Metal for taking Inijft'^ssions.—Ije&d, 3 lbs.; tin, 2 lbs.; bismuth, 5 lbs. SpanisliTiitania. — Iron or steel, 8 ozs. ; antimony, IGozs. ; nitre, 3 ozs. Melt and harden 8 ozs. tin with 1 oz. of the above compound. Another Tutania. — Antimony, 4 ozs.; arsenic, 1 oz., tin, 2 lbs. Gun-3Ietal. — Bristol brass, 112 lbs. ; zinc, 14 lbs. ; tin, 7 lbs. liivet Metal. — Copper, 32 ozs. ; tin, 2 ozs. ; zinc, 1 oz. Rivet Metal, fob Hose. — Copper, 64 lb.s.; tin, 1 lb. Fasihle Allan (which melts in boiling water). — Bismuth, 8 ozs. ; tin, 3 ozs. ; lead, 5 ozs. Fusible Alloy, foe silveking Glass. — Tin, 6 ozs.; lead, 10 ozs. ; bismuth, 21 ozs. ; mercury, a small quantity. Solder, for Gold. — Gold, 6 pwts. ; Silver, 1 pwt. ; copper, 2 pwts. Solder, for Silver. — (For the use of jewellers.) — Fine silver, 19 pwts. ; copper, 1 pwt. ; sheet brass, 10 pwts. White Solder, for Silver. — Silver, 1 oz. ; tin, 1 oz. White Solder, for R.used Britanni.v Ware.— Tin, 100 lbs.; copper, 3 ozs. ; to iiiukc it free, add lead, 3 ozs. Jiest Soft Solder, for Cast BritanniaWake — Tin, 8 lbs.; lead, 5 lbs. YelloiV Solder, for Br^vss or Copper. — Copper, 1 lb. ; zinc, 1 lb. Soft Cement, for Steam-Boilers, Ste.am-Pipes, Ac— Red or white lead, iu oil, 4 parts; iron borings, 2 to 3 parts. J ford Cement. — Iron borings and salt water, and a small quantity of sal-ammoniac with fresh water. Stat iia rij ]iron::e. — Dareet has discovered that this is com- po.s('d of copper, 01. 1; zinc, 5."); load, 1.7; tin, 1.4. Bronze for Cannon of large CVrftftrc— Copper, 90; tin, 7. Bronze for Cannon of small Calibre.— Goiiprr, 03: tin, 7. Bronze for Medals. — Copper, 100; tin, 8. Altoff for <'i/mbals.~Coi)i>cr, 80; tin, 20; Metal for tin' Mirrors of Jie/leefing Teleseopes.^ Copper, K.iJ; tin, DO, PRACTICAL MECHANICAL RECEIPTS. 245 White uLrge}Uan — Copper, 8; nickel, 3; zinc, 35. This beautiful composition is in imitation of silver. Chinese Silver. — M. Mairer discovered the following pro- portions : Silver, 2.5; copper, 65.24; zinc, 19.52; nickel, 13; cobalt of iron, 0.12. Tatciuig. — Copper, 8; nickel, 3; zinc, 5. Printing Churacters. — Lead, 4; antimony, 1. For stereo- type plates — Lead, 9 ; antimony, 2 ; bismuth, 2. Orange Dye for Wood. — Let the veneers be dyed by either of the methods given for a fine deep yellow, and while they are still wet and saturated with the dye, transfer them to the bright red dye, till the color penetrates equally throughout. Silver-Grag Dge for Wood. — Expose any quantity of old iron, or, what is better, the borings of gun-barrels, &c., in any convenient vessel, and from time to time sprinlde them with muriatic acid, diluted in 1 times its quantity of water, till they are very thickly covered with rust; then to every 6 pounds add 1 gallon of water in which has been dissolved 2 ounces salt of tartar (carbonate of potassa); lay the veneers in the copper, and cover them with this liquid ; let it boil 2 or 3 hours till well soaked, then to every gallon of liquor add \ pound of green copi^eras, and keep the whole at a moderate temperature till the dye has sufiiciently penetrated. To dye Veneers. —Some manufacturers of Germany, who had been supplied from Paris with veneers, colored throughout their mass, were necessitated by the late war to produce them themselves. Mr. Puscher states that experiments in this direc- tion gave in -the beginning colors fixed only on the outside, while the inside was untouched, until the veneers were soaked for 24 hours in a solution of caustic soda containing 10 per cent. of soda, and boiled therein for \ hour; after washing them with sufficient water to remove the alkali, they may be dyed through- out their mass. This treatment with soda eflfects a general dis- integration of the wood, whereby it becomes, in the moist state, elastic and leather-like, and ready to absorb the color; it must then, after dj'eing, be dried between sheets of paper and subject- ed to pressure to retain its shape. To dye Fcweer.s ^?«cfc.— Veneers treated as in last receipt and left for 24 hours in a hot decoction of logwood (1 part log- wood to 3 water), removing them after the lapse of that time, and, after drying them superficially, putting them into a hot sohition of copperas (1 part copperas to 30 water), will, after 24 hours, become beautifully and completely dyed black. To stain Wood like Ebony. — Take a solution of sulphate of iron (green cojiperas), and wash the wood over with it 2 or 3 times; let it dry, and apply 2 or 3 coats of a strong hot decoction of logwood; wipe the wood, when dry, with a sponge and water, and polish with linseed oil. 246 PRACTICAL MECHANICAL RECEIPTS. To dye Veneers Yellow. — A solution of 1 part picric acid in GO water, with the addition of so much ammonia as to become jjerceptible to the smell, dyes veneers yellow, which color is not in the least affected by subsequent varnishing. To dye Yeneern Hose- Color. — Coralline dissolved in hot water, to which a little caustic soda and one-fifth of its volume of soluble glass has been added, proiuces rose-colors of different shades, dependent on the amount of coralline taken. To dye Veneers Silver-Gray.— The only color which veneers will take up, without previous treatment of soda, is silver-gray, produced by soaking them for a day in a solution of 1 part copperas to 100 parts water. Black Stain for Immediate Use.— 'Boil J pound chip logwood in '.i quarts water, add 1 ounce pearlash, and apply it hot to the work with a brush. Then takei poiand logwood, boil it as before in 2 quarts water, and add I ounce verdigris and J ounce green copperas ; strain it off, put in \ i)ound rusty steel filings; with this, go over the work a second time. To.'itain Wood li (/Jit Mahogany <7o/or.— Brush over the surlixco with dihitt;d nitrous acid, and when dry ai)ply the following, with a soft ])rush : dragon's blood, 4 ounces ; com- mon soda, 1 ounce ; spirits of wine, 3 pints. Let it stand in a warm place, shake it frequently, and then strain. Repeat the application until the proper color is obtained. To stain Dark Mahotjauy Color.— Boil l pound mad- der and 2 ounces logwood in 1 gallon water ; then brush the wood well over with the hot licpiid. When dry, go over the whole with a solution of 2 drams pearlash in 1 quart of water. Jieeehirood Mah oga ny. —Dissolve 2 ounces dragon's blood and 1 oiance aloes in 1 (piart rectified spirit of wine, and apply it to the surface of the wood i)reviously well polished. Or: Wjxsli over the surface of the wood with atjuafortis, and when thorough- ly dry give it a coat of the above varnish. Or: Boil 1 jiound log- wood chips in 2 (]uarts water, and add 2 haudfuls of walnut \^Q^'\\ boil again, then strain, and add 1 pint good vinegar: apjily a.s above. A rti/ieial 3Iahoyany.— The following method of giving any species of wood of a elosi^ grain tlie apjx'aranco of mahogany in texture, density, and polish, is said to be practised in Franco with success. The surface is ]>laned smooth, and the wood is tlien rubbed witli a solution of nitrous acid; 1 ounce dragon's l)lood is dissolved in nearly a ])int of spirits of wine; this, and ^ ounce carbonate of soila, are tlien to Ixs inixe(l together and fil- ttTiid, and the li(iuid in tliis thin state is to be laid on with a soft brush. This jmxjess is to bo repeated, uiid in a short inttirval afterward the wool 1 jiossesses the external aii]iearance of mahogany. When llio ]tf)lisli diminishes in brilliancy, it may bo restored by the use of a little cold-drawn linseed oil. PRACTICAL MECHANICAL RECEIPTS. 247 To stain Mahogantf Color.— Vnre Socotrine aloes, 1 ounce; dragon's bloo^l, Jounce; rectified spirit, 1 pint; dissolve, and apply 2 or 3 coats to tbe surface of the wood; finish off with ■wax or oil tinged with alkanet. Or : Wash over the wood with strong aquafortis, and when dry, apply a coat of the above var- nish; polish as last. Or: Logwood, 2 ounces; madder 8 ounces; fustic, 1 ounce; water, 1 gallon; boil 2 hours, and apply it several times to the wood boiling hot; when dry, slightly brush it over with a solution of pearlash, 1 ounce, in water, 1 quart; dry and polish as before. Or: Logwood, 1 part; water, 8 parts. Make a decoction and apply it to the wood; when dry, give it 2 or 3 coats of the following varnish: dragon's blood, 1 part; spirits of wine, 20 parts. Mix. Fine Black Stain.— BoW 1 pound logwood in 4 quarts water, add a double handful of walnut-peel or shells; boil it up again, take out the chips, add 1 pint best vinegar, and it will be fit for use ; apply it boiling hot. This will be improved by ap- l^lying a hot solution of green copperas dissolved in water (an ounce to a qi;art), over the first stain. To unit ate Hosewood. — Boil 4 pound logwood in 3 pints ■water till it is of a very dark red; add" \ ounce salt of tartar 'car- bonate of potassa). While boiling hot, stain the wood with 2 or 3 coats, taking care that it is nearly dry between each ; then, with a stiff flat brush, siich as is used by the painters for grain- ing, form streaks with the black stain above named (see last re- ceipt), which, if carefully executed, will be very nearly the aj)- pearance of dark rosewood; or, the black streaks may be put in with a camel's hair pencil, dijiped in a solution of copperas and verdigris in a decoction of logwood. A handy brush for the pur- pose may be made out of a flat bri;sh, such as is used for varnish- ing; cut the sharp points off, and make the edges irregular, by cutting out a few hairs here and there, and you will have a tool ■which will accurately imitate the grain. To polish Varnish is certainly a tedious process, and con- sidered by many as a matter of difficulty. Put 2 ounces pow- dered tripoli into an earthen pot or basin, with water sufficient to cover it ; then with a piece of fine flannel four times doubled, laid over a piece of cork rubber, proceed to polish the varnish, always wetting it well with the tripoli and water. It will be known when the process is complete by willing a part of the work with a sponge, and observing whether there is a fair and even gloss. Clean off with a bit of mutton-suet and fine flour. Be careful not to rub the work too hard, or longer than is neces- sary to make the face jjerfectly smooth and even. The French 3Iethoink' When all the cohir is extracted, strain it off, and to every pint add J gill spirits of turp.'iitine. This will bo a very superior composition for soft luul light mahogany. PEACTICAL MECHANICAL EECEIPTS. 249 Mixture fov cleanhif/ Furniture. — Cold-drawn linseed oil, 1 quart ; spirits of wine and vinegar, J pint each ; butter (terchloride) of antimonj-, 2 ounces; sj^irits of turjsentine, \ pint. This mixture requires to be well shaken before it is used. A lit- tle of it is then to be poui-ed upon a rubber, which must be well applied to the surface of the furniture ; several applications will be necessary for new furniture, or for such as had previously been French polished or rubbed with bees' wax. Furniture Polish. — Dissolve 4 ounces best shellac in 2 pints 95 per cent, alcohol ; add to this 2 pints linseed oil, and I pint spirits of turi^entine ; when mixed, add -t ounces sulphuric ether, and 4 ounces ammonia water ; mix thoroughly. Shake ■when used, and apply with a sponge lightly. This is an excel- lent article, especially where the varnish has become old and tarnished. Furniture Polish — Bees' wax, i pound; alkanet root, i ounce ; melt together in a pipkin untfl the former is well col- ored. Ihen add linseed oil and spirits of turpentine, of each J gill ; strain through a jiiece of coarse muslin. Furniture Puste. — Turpentine, 1 pint ; alkanet root, \ ounce ; digest until sufficiently colored, then add bees' wax, scraped small, 4 ounces ; put the vessel into hot water and stir until dissolved. If wanted pale, the alkanet may be omitted. Pest Frenrh Polish. — Shellac, 3 parts ; gum mastic, 1 part ; gum sandarach, 1 part ; spirits of wine, 40 parts ; the mastic and sandarach must first be dissolved in the spirits of wine, and then the shellac ; the process may be performed by putting them into a bottle loosely corked, and placing it in a vessel of water heated to a little below 173^ Fahr., or the boiling point of spirits of wine, until the solution be effected ; the clear solution may be poureil off into another bottle for use. Various receipts for the French polish have been published, in which ingredients are inserted that are insoluble in spirits of wine, and therefore useless; and others contain ingredients that are soluble in water, so as to render the mixture more easily injured. ' To WU.K Furniture. — In waxing, it is of great importance to make the coating as thin as possible, in order that the veins of the wood may be distinctly seen. The following prejiaration is the best for performing this operation : Put 2 ounces white and yellow wax over a moderate fire, in a very clean vessel, and, j when it is quite melted, add 4 ounces best spirits of turpentine. Stir the whole until it is entirely cool, and you will have a po- made fit for waxing furniture, which must be rubbed over it according to the usual method. The oil soon penetrates the pores of the wood, brings out the color of it, causes the wax to adhere better, and jDroduces a lustre equal to that of varnish, without being subject to any of its inconveniences. The polish may be renewed at any time by rubbing it with a piece of fine cork. IX* 250 PRACTICAL MECHANICAL RECEIPTS. To French JPolish. — The varnish being prepared (shellac), the article to be polished being finished off as smoothly as possi- ble with glass pajjer, and the rubber being made as directed below, proceed to the oijeration as follows ; The varnish, in a narrow-necked bottle, is to be applied to the middle of the flat face of the rubber, by laying the rubber on the mouth of tlie bottle and shaking up the varnish once, as by this means the rubber will imbibe the projier quantity to varnish a considerable extent of surface. The rubber is then to be inclosed in a soft linen cloth, doubled, the rest of the cloth being gathered up at the back of the rubber to form a handle. Moisten the face of the linen with a little raw linseed oil, applied with the finger to the middle of it. Place the work opposite the light, pass the rubber quickly and lightly over its surface uniform!}' in small circular strokes, until the varnish becomes dry, or nearly so ; again charge the rubber as before with varnish (omitting the oil), and repeat the rubbing, until three coats are laid on, when a little oil may be applied to the rubber, and two coats more given to it. Proceed in this way until the varnish has acquired some thickness ; then wet the inside of the linen cloth, before applying the varnish, with alcohol, or wood najjlitha, and rub quickly, lightly, and uniformlj-, the whole surface. Lastly, wet the linen cloth with a little oil and alcohol without varnish, and rub as before till dr}'. Each coat is to be rubbed until the rag appears dry ; and too much varnish must not be put on the rag at a time. Be also very particular in letting the rags be very clean and soft, as the polish depends, in a great measure, on the care taken in keeping it clean and free from dust during the operation. If the work be porous, or the grain coarse, it will be necessary to give it a coat of clear si/,e previous to commencing with the polish ; and, when dry, gently go over it with vi>ry fine glass paper. The size will fill up the i)ores, and prevent the waste of the ])olish, by being absorbed into the wood, and bo also a saving of considerable time in the ojieration. To vial^c a Freiirh Polish Itubhrr. — Eoll up a strip of tliick woolen cloth which lias been torn off, so as to form a Boft elixstic edge. It should form a coil, from 1 to 3 inches in diameter, according to the size of the- work. This rubber is to bo securely bound with tliread, to prevent it from uncoiling •when it is used. J'olishinf/ Paste. — Take 3 ounces white wax, \ ounce Ciw- tilesoaji, I gill turpentine. Shavo the wax and soap very fine, and ]>ut Iht- wax to the turpentine ; let it stand 21 hours ; then boil the soap in I gill water, and add to the wax and turpentine. Tliis has been highly recomnn'nded. Sftiiddrtirh French J'olish—^hoUaG, 2 pounds; mastio and sandar.ieh (botli in jiowder*, of eiudi 1 ounce ; copal varni.sh, 12 f)uii(;i's ; alcohol, 1 gallon. All the above are made in the cold by fr< quf^ntly stirring or sliaking the ingredients together in a well-cloKcd bottle or other vessel. I'Yeuch polish is used without filtering. PRACTICAL MEOHANICAL RECEIPTS. 251 French Polish. — To 1 pint spirits of Avino a IJ J- ounce gum shellac, the same quantity gum lac, and ^ ounce gum sandarach; put these ingredients into a stone bottle near a tire, frequently shaking it ; when the various gums are dissolved it is fit for use. Fretwli Polish. — Take 2 ounces wood naphtha, \ ounce best shellac, 1 dram gum benzoin; crush the gums, mix them with the naphtha in a bottle; shake them frequently till dissolved; it is then ready for use. This is the clear polish. Take a little cot- ton wool, apply a little of the polish to it, cover it tightly with a linen rag, to which apply a drop of linseed oil, to jirevent it from sticking to the wood; use your rubber gently, polishing from a centre in a circular manner; finish with a droj) of spirits of wine on a clean rubber, which will extract the oik To sta in or color French Polish.— ^Vood may be stained or grained any color or design, by mixing it with the polish, or dipping the rubber in the color t finely powdered \ at the time you apply the polish. To produce a rod, dij) the cotton into dragon's blood (finely i^owdered), immediately apj^lying the polish; then cover with the linen, and polish. For yellow, use the best chrome yellow. For blue, ultramarine blue, or indigo. For black, ivory or lamp-black, Ac. Graining is produced by touching or streaking the wood with the color, as above, in ir- regular lines or marks, and in such shapes as the fancy may sug- gest, then finishing it with a coat of clear polish. Water-Proof Polish.— Take 1 pint spirits of wine, 2 oz. gum -benzoin, \ ounce gum sandarach, and \ ounce gum anime; these must be put into a stoppered bottle, and placed either In a sand-bath or in hot water till dissolved; then strain the mix- ture, and, after adding about \ gill best clear poppy oil, shake it well up, and put it by for iise. BrigJif Polish. — 1 pint spirits of wine, 2 ounces gum-ben- zoin, and 5 ounce gum-sandarach, put in a glass bottle corked, and placed in a sand-bath or hot water until you find all the gum dissolved, will make a beautiful clear polish for Tunbridgeware goods, tea-caddies, &c. It must be shaken from time to time, and, when all dissolved, strained though a fine muslin sieve, and bottled for use. Prepared Spirits for Finishing Poli.sh— This prepa- ration is useful for finishing after any of the foregoing recei^Dts, as it adds to the lustre and durability, as well as removing every defect, of the other polishes; and it gives the surface a most bril- liant appearance. Take J pint best rectified spirits of wine, 2 drams shellac, and 2 drams gum-benzoin. Put these ingredients in a bottle, and keep it in a warm place till the gum is all dis- solved, shaking it frequently; when cold, add 2 tea-spoonfuls of the best clear white l opjiy oil; shake them well together, and it is fit for use. This preparation is used in the same manner as the foregoing polishes; but, in order to remove all dull places, the pressure in rubbing may be increased. 252 PllACTICAL MECIIAXICAL RECEIPTS. Ilrnv to {jh'C lilacJc Waluut a Darh Dead Smooth Siir/'(tce. — Take asphaltiim, pulverize it, place it in a jar or bottle, pour over it about twice its bulk of turpentine or benzole, jmt it in a warm place, and shake it from time to time. V hen dissolved, strain it and Jpply it to tlie wood with a cloth or stiff brush. If it should make too dark a stain, thin it with turpen- tine or benzole. This will dry in a few hours. If it is des-ired to bring out the grain still more, apply a mixture of boiled oil and turpentine; this is better than od alone. Put no oil with the asphaltnm mixture, as it will dry very slowly. "When the oil is dry the wood can be polished with the following: Shellac var- nish, of the usual consistency, 2 parts; boiled oil, 1 part. Shake it well before using. Ajiply it to the wood by putting a few drops on a cloth and rubbing briskly on the wood for a few moments. This polish works well on old varnished fuiniti;re. Polish for Tamers' TFor/c— Dissolve sandarach in spirits of wine in the proportion of 1 oz. sandarach to .', junt of spirits; next shave bees' wax, 1 oz., and dissolve it in a sufficient quan- tity of spirits of turpentine to made it into a paste ; add the lormer mixture by degrees to it; then with a woolen cloth apj ly it to the work while it is in motion in the lathe, and with a soft linen rag polish it. It will apjiear as if highly varnished. To nrepare the FiUin(/-uj} Color for eva'iueUhig IFooa. — ihe filling-up color, which forms the body of the enamel, is of the greatest importance to the ultimate success of the work. Of this material there are several kinds manulactured — black, brown, and yellow, for coach j ainters, jaj annus, and others; but for use in interior decoration it is })reitralle to use the white lead filling, as, by adding the necessary staining colors (which do not affect the properties of the enamel), a solid body of color is formed, of the same tint, or nearly so, as that with wliich the woric is rc(iuired to be finished, thus doing away with the objections that may be urged against the black or dark-col- ored tilling. It is evident that if work which has to be linihlud white, or with very light tints of color, be filled np with dark- colored filling, the number of coats of paint required to obscure or kill the dark color will be so manj' that there will be danger of tlie work becoming rough and uneven in parts. The -white lead should be ground stiff in turpentine, and abo\it one-f(jurth l)art of the ordinary white Lad, ground in oil added to it. in order to jirevent the enamel cracking, which it has a tendency to do, cxccjit there be some little oil mixed with it. A sufficient cjuantity of polishing copal or best carriage varnish she)ul(l neiw bo aebled to bind it so that it will rub down easily, which fact e'an- not be properly ascertained exccjit by actual trial, inasmuch as the drying ])roperties of varnislu^s vary, and other causes influ- ence tlu! matteT Iffliere be too much varnish in the stuff the work will be exijoedingly dillicult to cut down, and if too little, it is apt to break up in rubbing, so that it is always the safest )>lan to try the enamel ce)lor before commencing anything im- pf)rtant. PRACTICAL MECHANICAL RECEIPTS. 253 Strong JPoUsJi. — To bo used in tlie carved parts of cabinet- ■work with a brush, as in standards, pillars, claws, &c. Dissolve 2 ounces seed lac and 2 ounces white resin in 1 jjint spirits of wine. This varnish or polish must be laid on warm, and if the work can be warmed also, it will be so much the better; at any rate, moisture and dampness must be avoided. To prepare tlie Pumice-Stone for enamelling Wood. — The pumice-stone to be used should be of different degrees of fineness, and should be carefully selected, so as to be sure that it is free from any gritty substance. It is sold ready ground, but in situations where it cannot be readily got, it may be prepared from the lump, by grinding or crushing with a stone and muUer, and then passed through fine sieves or muslin; by using these of different degrees of texture the ground pumice may be produced of different degrees of fineness. Unless great care be exercised in this matter, it will be found that particles of grit will be mixed with it, vrhich make deep scratches on the work, thus causing endless trouble and annoyance, besides spoiling the work. The gr>?atest care is also required in keeping the felt clean and free from grit. Many workmen are careless in this matter, and, when working, set down the felt on the step- ladder or floor, thus allowing particles of sand or grit to get upon it. To cut down or jyrepare the Surface for poUshing. — In cutting down, it is best to use a piece of soft liimp pumice stone to take off the rough parts. The work should then be wet with a sponge; the felt must first be soaked in water, then dipped into the powdered pumice, and the work rubbed with it, keeping it moderately wet, and rubbing with a circular motion, not straight up and down and across, and with a light touch, using only just as much pressure as will cause the pumice to bite, which vdW be very clearly felt while the hand is in motion. Care and patience are reqiiired to do this properly, for if the pressure be too great it forces the pumice into the body of the filling color, and scratches it instead of cutting or grinding it fairly down. No huiTy will avail in doing this work, it must have its time; hurry often defeats the end in view, and often causes much unneces- sary labor. A scratch, caused by want of care and too much haste, will often thro\v the work back for days, and involve the cost and labor of refilling. In pi-actice the purpose is best an- swered by using the pumice-stone, the coarser kind first, then the medium, and finishing with the finest last. It will be found advantageous to let a day elapse between the nibbing, for when the surface is cut do%\-n the filling will in all cases be softer un- derneath, and if it be allowed to stand for a daj', the newly ex- posed surface gets harder, and of course rubs down better. The pumice-stone shoiild be wel washed off the work occasionally, in order to see what progress is being made, and if it require more rubbing or not. If, after the first nibbing, the surface be found not suflicicntly filled up, it may have one or more addi- tional coats of filling before much labor has been suent ujion it. 2o\: TRACTICAL MECHANICAL RECEIPTS. To laif the Color on I^natnelled Wood.—ThQ color, boiug properly ruixeil, shoulil be laid ou the wtJrk in the ordi- nary manner, using it rather freely. It may be as well to state here that no tilling should be put upon new work without the same havin^^ had 2 or 3 coats of ordinary oil } aint, nor on old work without its having one coat. This gives a foundation for the filling. Successive coats of the filling should now be laid on the work until there is a sufficient thickness to cut down to a level surface. One day should intervene between each coat, in order to allow it to harden in some degree. When a sufficient number of coats are put on (which number will, of course, de- pend upon the state of the work to be filled up), it should stand for 2 or 3 weeks, until it is Ihoroiighly hard; it will then be ready for cutting down, which is to bo done with a felt rubber, ground pumice-stone, and water. To prepare the liuhherfor eiuunellhif/ IFood.—The felt used should be sucli as the sculptoi'S use for polishing mar- ble, which varies in thickness from J to ^ an inch, and about 3 inches square. This should be fastened with resinous gum to square pieces of wood of the same size, but 1 inch thick, to as to give a good hold for tho hand in using. These pieces of wood covered with felt, may be made of any size or shape to fit moulded surfaces or other inequalities. Tinman's Solder. — Lead, 1 part; tin, 1 part. Pewterer's Solder.— Tin, 2 parts; lead, 1 part. Common Pewter. — Tin, 4 parts; lead, 1 i)art. Jiesf Peivter. — ^Tin, 100 parts; antimony, 17 parts. A Metal that expands in rooZ/iu/. -Lead, 9 parts; an- timony, 2 parts; bismutli, 1 part. This metal is very useful iu filling small defects in iron castings, Ac. Silrrr Coin of the United States —Vnre silver, 9 parts; alloy, 1 piut; the alloy of silver is line copper. Cold Coin of the United States.—Vnn^ gold. parts; alloy, 1 ])ait; tho alloy of gold is ^ silver and J copi)er (not to exceed \ silver). Silver Coin of (ireat Jiritain.—I'xire Hi\\er, 11.1 parts; copper, 0.9 part. Gold Coin of flreat Britain.— Vnro gold, 11 parts; cop- per, 1 ])art. I'revious to ISJO silver formed part of tlio alloy of gold coin; hence tho dill'i rent color of English gold money. Cast Tron Cement.— CAoAn borings or turnings of cast iron, Ki jiarts; sal-ammoniac, 2 i)arls; lliMir of sulj)hur, 1 part; mix them well together in a mnrlar and keep them dry. When ro- qiiirtul for use, talce of the mixture, 1 ])art ; clean borings, 20 parts; mix tiiorougldy, and add a Kuffieient (juantily of water. A little grindstone-dust added improves tho cement. PRACTICAL MECHANICAL RECEIPTS. 255 Queen's 3Iefal. — Tin, 9 laarls; autimony, 1 part; bismuth, 1 part; lead, 1 i:)art. Mode Platbiuui. — Brass, 8 parts; zinc, 5 parts. Booth's Patent Grease, for Railway Axles. — Water, 1 gal. ; clean tallow, 3 lbs. ; palm oil, G lbs. ; common soda, J lb. Or: Tallow, 8 lbs. ; palm oil, 10 lbs. The mixture to be heated to about 210° F., and well stirred till it cools down to about 70°, when it is ready for use. Cement, for Steam-Pipe Joints, &c., vmn r.ACED Flanges. — White lead, mixed, 2 parts; red lead, dry, 1 part; grind or other- wise mix them to a consistence of thin Jjutty, ajiply interposed layers with one or two thicknesses of canvas or gauze wire, as the necessity of the case may be. Olive Bronze Dip, for Brass. — Nitric acid, 3 ozs. ; muri- atic acid, 2 ozs.; add titanium or palladium; when the metal is dissolved, add 2 gals pure soft water to each pint of the solution. Brown Bronze Paint, for Copper Vessels. — Tincture of steel, 4 ozs. ; siiirits of nitre, 4 ozs; essence of dendi, 4 ozs.; blue vitriol, 1 oz. ; water, ^ pint. Mix in a bottle. Apply it with a fine brush, the vessel being full of boiling water. Varnish after the application of the 1 ronze. Bronze, for all Kinds of Metal. — Muriate of ammonia (sal- ammoniac , '1 drs. ; oxalic acid, 1 dr.; vinegar, 1 pint. Dissolve the oxalic acid first. Let the work be clean. Put on the bronze with a brush, repeating the operation as many times as may be necessary. Bronze Paint, for Iron or Brass. — Chrome green, 2 lbs.; ivo y black, 1 oz. ; chrome yellow, 1 oz. ; good japan, 1 gill; grind all together and mix with linseed oil. To bronze Crim-Barrels. — Dilute nitric acid with water and rub the gun-barrels with it; lay them by for a fow days, then rub them with oil, and polish them with bees-wax. For tinning Brass. — Water, 2 i^ailfuls; cream of tartar, ^ lb. ; salt, \ pint. Shaved or Grained Tin — Boil the work in the mixture, keeping it in motion during the time of boiling. Silverinf/ hy Heat. — Dissolve 1 oz. of silver in nitric acid ; add a small q.iiuitity of salt; then wash it and add sal-ammoniac or 6 oz. of salt and white vitriol; also \ oz. of corrosive subli- mate; rub them together till they form a paste, rub the i^iece which is to b 3 silvere 1 with the paste, heat it till the silver runs, after which dip it in a weak vitriol jjickle to clean it. 31ixtHre for Silverinfj. — Dissolve 2 ozs. of silver with 3 grains of corrosive sublimate; add tartaric acid, -ilbs. ; salt, 8 qts. SolveTtt for Gold — Mix equal quantities of nitric and mu- riatic acids. 256 PRACTICAL MtlCHANICAL RECEIPTS. To separate Silver from C'oy>y;f'i'.— Mix sulphuric acid, 1 part; nitric acid, 1 part; water, 1 part; boil the metal in the mixture till it is dissolved, and throw in a little salt to cause the silver to subside. 1't'irnisli, FOB SMOOTH Moulding Patterns. — Alcohol, 1 pil ; shellac, 1 lb. ; lamp or ivory black, siifficient to color it. FinrlildcJc Frti'J* Is/*, fok Coaches. -?>Ht, in an iron ]>ot, amber, 32 ozs. ; resin, 6 ozs. ; aspluiltuni. o;«; drying linseed oil, 1 pt ; when partlj' cooled, add til of turpentine, wormed, Ipt. Chinese White Copper. — Copper, 40.4 parts; nickel, 31. G parts; zinc, 2.5.4 parts, and iron, 2.6 parts. 3I(itth('iin Gold. — Copper, 3 parts; zinc, 1 part, and a small quantity of tin. Alloij of the Stmulard Measnre.repare or apply kalsomine; few painters can do so successfullj- Paris white is often made use of for it, but it is not the genuine article. (See next receipt. ) The kaisomining mixture may be colored to almost any required tint, by mixing appropriate col- oring matter with it. To Jxalsoiniup- Jfalls. — In case the wall of a room, say 16 by 2) feet square, is to be kalsomined with two coats, it will re- quire \ pound light-colored glue and 5 or C pounds Paris white. (See last receipt.) Soak the glue overnight in a tin vessel con- taining about a quart of warm water. If the kalsomine is to be applied the next day, add a pint more of clean water to the glue, and set the tin vessel containing the glue into a kettle of boiling water over the fire, and continue to stir the gliie until it is well dissolved and quite thin. If the glue-pail be placed in a kettle of boiling water, the glue will not be scorched. Then, after put- ting the Paris white into a large water-pail, jiour on hot water, and stir it until the liquid appears like thick milk. Now mingle the glue liquid with the whiting, stir it thoroughly, and apply it to the wall with a whitewash-briish, or with a large paint-brush. It is of little consequence what kind of an instrument is employed in laying on the kalsomine, provided the litpiid is spread smooth- ly. Expensive brushes, made expressly for kalsomining, maj' be obtained at brush factories and at some drug and hardware stores. But a good whitewash-brush, having long and thick hair, will do very well. In case the liquid is so thick that it will not flow from the brush so as to make smooth work, add a little more hot water. When aj^plying the kalsomine, stir it fre- quently. Dip the brush often, and only so deep in the liquid as to take as much as the hair will retain without letting large drops fall to the floor. If too much glue be added, the kalso- mine cannot be laid on smoothly, and will be liable to crack. The aim should be to apply a thin layer of sizing tliat cannot be brushed off" with a liroom or dry cloth. A thin coat will not crack. A Fine IFJtitcwash for Walls. — Soak |- pound of glue ovei'night in tepid water. The next day put it into a tin vessel with a qiiart of water, set the vessel in a kettle of water over a fire, heep it there till it boils, and then stir till the glue is dis- solved. Next put from 6 to 8 pounds Paris white into another vessel, add hot water, and stir until it has the appearance of milk of lime. Add the sizing, stir well, and apply in the ordinary way. while still warm. Except on very dark and smoky walls and ceilings, a single coat is sufficient. It is nearly equal in bril- liancy to zinc-white (a far more expensive article), and is very highly recommended by those who hiwe used it Paris white is sulphate of baryta, and may be found at any drug or paint store. 260 PRACTICAL MECHANICAL KECEIPTS, 1o color jyhiieiVflsJi. — Coloring matter may be put in and made of any shade. iSpanisli brown stirred in will make red pink, more or less deep according to the quantity. A delicate tinge of this is very pretty for inside walls. Finely pulverized com- mon clay, -well mixed with Spanish brown, luakes a reddish stone color. Yellow ochre stirre 1 in makes a yellow wash, but chrome goes further and makes a color generally esteemed prettier. In all these cases the darkness of the shades of course is determined by the quantity of coloring used. It is difficult to make rules, because tastes are different; it would be best to try experiments on a shingle and let it dry. Green must not be mixed with lime. The lime destroys the color, and the color has an effect on the whitewash, which makes it crack and peel. "When walls have been badly smoked, and you wish to have them a clean white, it is well to squeeze indigo plentifully through a bag into the water you use, before it Ls stirred in the whole mixture. WUitt'ii'dsh fov Outside irorJ^.—Tuke of good quick- lime i a bushel, slack in the usual manner, and add one pound common salt, I pound sulphate of zinc (white vitriol \ and 1 gal- lon sweet milk. The salt ami the white vitriol should be dis- solved before they are added, when the whole shoiild be thor- oughly mixed with sufficient water to give the proper consist- ency. The sooner the mixture is then applied the better. To niljc Whitewash.— PovLT boiling water on unslacked lime, and stir it occasionally while it is slacking, as it will make the paste smoother. To 1 peck of lime add a quart of salt and J ounce of indigo dissolved in water, or the same (quantity of Prus- sian blue finely powdered; aid water to make it the proper thickness to put on a wall. One pound soap will give gloss. To keep jyhiteivash.—Kecp the lime covered with water and in a tub which has a cover, to prevent dust or dirt from fall- ing in. If the water evaporates the lime is useless, but if kept covered it will be good as long as any remains. To whiten Smoked Walls, -k method of cleaning and whitlied in i:i()dcs that will suggest themselves to any intolliyont artist, to high-cla.ss decoration PllACTICAL MECHANICAL RECEIPTS. 263 Dtirnhir Coinptpnitioii fov Ornaments. — This is fre- qaiiULJy use 1, instead ot plaster of Pims, tor the ornamentaJ parts oi builaings, as it is more durable, and becomes in time as bard as stone itself. It is of great use in the execution of the decorative parts of architecture, and also in the finishings of pictui'e-frames, being a cheaper method than carving, by nearly bJ per cent. It is made as folJows : 2 pounds best whiting, 1 pound glue, and J pound Unseed oil are heated together, t^e comijosiiion being continually stirred until the ditierent sub- stances are thoroughly incorporated. Let the compound cool, and then lay it on a stone covered with powdered whiting, and heat it well until it becomes of a tough and firm consistence. It may then be put by for use, covered with wet cloths to keep it fresh. When wanted for use it must be cut into pieces adapted to the size of the mould, into which it is forced bj' a screw press. The ornament, or cornice, is fixed to the frame or wall with glue, or with white lead. Coavfte Stuff for Plasterinf/.—Cnavae stuff, or lime and hair, as it is sometimes called, is prepared in the same way as common n.ortar, with the addition of hair procured from the tanner, which must be well mixed with the mortar by means of a three-pronged rake, until the hair is equally distributed throughout the comp.osition. The mortar should be first form- ed, and when the lime and sand have been thoroughly mixed, the hair should be added bj^ degrees, and the whole so thorough- ly united that the hair shall appear to be equally distributed throughout. Concrete. — A compact mass, composed of pebbles, lime, and sand, employed in the foundations of buildings. The best pro- portions are 60 parts of coarse pebbles, 25 of rough sand, and 15 of lime: others recommend bO jsarts pebbles, 40 parts river sand, and only 10 parts lime. The pebbles should not exceed about |- pound each in weight. Abbe Moigno, in his valuable scientific journal, "Les Mondes," relates his personal experience with a concrete formed of fine wrought and cast iron filings and Port- land cement. The Abbe states that a cement made thus is hard enough to resist any attempts to fracture it. As he states that the iron filings are to replace the sand usually put into the mix- ture, we presume that the relative quantities are to be similar. Concrete Floors and Walha. — Compost for barn and kitchen floors : After the ground on which the floor is intended to be made is levelled, let it be covered to the thieknesj of 3 or 4 inches with stones, broken small, and well rammed down ; upon which let there be rtin, about \h inches above the stones, 1 part by measure calcined ferruginous marl, and 2 parts coarse sand and fine gi-avel, mixed to a thin consistence with water. Before this coating has become thoroughly set, lay upon it a coat of cal- cined marl, mixed with an equal part of fine sand, 1 to liV inches thick, levelled to an even surface. The addition of blood will render this compost harder. 26-1 PRACTICAL MECHANICAL RECEIPTS. Rotnan Cement. — Calcine 3 parts of any ordinary clay, and mix it witia 2 parts lime ; grind it to powder, and calciuo again. This makes a beautiful cement, improjierly called lloman, since the preparation was entirely iinknown to the Romans. Gd^ige Stuff. — This is chiefly used for mouldings and cor- nices which are run or formed with a wooden mould. It consists of about 1-5 plaster of Paris, mixed gradually with 4-5 line stuflf. When the work is reqxiired to set very expeditiously, the propor- tion of plaster of Paris is increased. It is often necessary that the plaster to be used should have the property of setting imme- diately it is laid on, and in all such cases gauge stuff is used, and consequently it is extensively employed for cementing ornaments to walls or ceilings, as well as for casting the ornaments them- selves. To Lacquer Bt-a.-^n-lforJc—lt the work is old, clean it first, according to the directions hereafter given ; but if new, it will merely re(iuire to be freed from dust, and rubbed with a piece of wash-leather, to make it as bright as possible. Putthe work on a hot iron plate (or upon the top of tlie stove), till it is moderately heated, but not too hot, or it will Idistcr the lacquer: then, according to the color desired, take of the f;)l!owing prepar rations, and, making it warm, lay hold of the work with a piiir of pincers or pliers, and with a soft brush apply the lacquer, being careful not to rub it on, but stroke the brush gently one way, and ] lace the work on the hot plate again till the vanii;h is hard ; but do not let it remain too long. Experience will best tell you when it shoiild be removed. Some, indeed, do not place it on the stove or plate a second time. If it should not be (jnito covered, you may repeat it carefully; and, if pains be taken v/ith the lacquer, it w'ill look etjual to metal gilt. To clean old Bra.ss-lf'otJc for Lacqiieriut/.—Malie a strong lye of wood ashes, which may be strengthened by soa])- lees ; put in the brass-work, and the lac(pier will soon come off; then have ready a mixture of aquafortis and water, sufficiently strong to take off the dirt ; wasli it aft(U-ward in clean water, and laccpicr it with such of the following compositions as may be most suitable to the work. (ilold Larqner.—Tnt into a clean four-gallon tin, 1 pound ground turmeric, 1.', ounces jjowdered gamhoge, \]} (umces iiow- dered gum sandarach, 3 i)onnd sliarh- ot is then removed from the fire, and after standing 10 minutes opened for evaporation, all tlie articles will bo found covered with tlie above described coating. Tiiis lac(|uer is not only a i)rotection against oxidation of metals, but will stand also a considerable heat, only disaiipearing at l)eginning redness, and therefore its useful ap- t)li(;aiion for ovens and T\irnactts. The coating ])roduced is thin, ustrous, and cannot easily be scratched. Fine iron-ware arti- cles, such as sieves, are in this manner coated with remarkable evenness, which cannot be accom])lished in anv other way. Articles made of tin, or soldered, cannot bo subjected to this process, as they would fuse. Snndler articles, like hooks and eves, r(^c(!iv(! this coating l)y heating tliein togetlier with small pieces of bituminous coal in a cylindrical sheet iron drum like t'.uit used for roasting coUee, until they present the desired lus- trous black ap])earance. PRACTICAL MECHAXICAL RECEIPTS. 267 Lacquer for Philosophical Instriiinents. — Gamboge, 1^ ounces ; gum sandaracli, 4 ounces ; gum elemi, 4 ounces ; best dragon's blood, 2 ounces ; terra merita, IJ ounces ; oriental saflfron, 4 grains ; seed-lac, 2 ounces ; pounded glass, 6 ounces ; pure alcohol, 40 ounces. The dragon's blood, gum elemi, seed- lac, and gamboge, are all pounded and mixed with the glass. Over them is jioured the tincture obtained by infusing the saifron and terra merita in the alcohol for 24 hours. This tincture, before being poured over the dragon's blood, etc., should be strained through a piece of clean linen cloth, and strongly squeezed. If the dragon's blood gives too high a color, the quan- tity may be lessened according to circumstances. The same is the case with the other coloring matters. In choosing the terra merita, select that which is sound and comiiact. This lacquer has a very good effect when applied to many cast or moulded articles used in ornamenting furniture, the irregularity of sur- face of which would render it difficult, if not impossible, to pol- ish in the ordinary manner. To frost AUnniniltn. — The metal is plunged into a solu- tion of caustic potash. The surface, becoming frosted, does not tarnish on exposure to the air. JPlatiim HI— also called platina— is the heaviest substance but one known, having a sijecific gravity of fully 21, which may be raised to about 21.5 by hammering. It is whiter than iron, harder than silver, infusible in the hottest furnace, and melts only before the compound blow-j^ipe at a heat of about 3080° Fahr. On this account it is valuable for making capsules, &c., intended to resist strong heat. Platinum undergoes no change by ex- posure to air and moisture, or the strongest heat of a smith's forge, and is not attacked by any of the pure acids, but is dis- solved by chlorine and nitro-muriatic acid (aqua regia), though with more difficulty than gold. Spongy and powdered platinum possess the remai'kable property of causing the union of oxygen and hydrogen gases. It is chiefly imported from South America, but is also found in the Ural SIountaLns of Eussia, in Cej'lon, and a few other places. Platinum, when alloyed with silver, is soluble in nitric acid ; the pure metal is dissolved by aqua regia, and is more or less attacked by caustic alkali, nitre, phosi^horus, &c., with heat. Platinum is preciijitated from its solutions by deoxidizing substances under the form of a black powder, whicli has the power of absorbing oxygen, and again imparting it to combustible substances, and thus cav^sing their oxidation. In this way alcohol and pyroxilic spirit may\)e converted into acetic and formic acids, etc. To estiituite the JPiirit!/ of Antimony. — Treat pulver- ized antimony witli nitric acid ; this oxidizes the antimony, and leaves it in an insoluble state, whilst it dissolves the other metals. Collect the oxide on a filter, wash, dry, ignite, and weigh it. This weight, multiplied by .843 gives the weight of pure metal in the sample examined. If this has been previously weighed, tha percentage cf puio metal is easily arrived at. 268 PRACTICAL MECHANICAL RECEIPTS. To jyiirifi/ JPlatiniini. — The native alloy (crude platinum) is acted upon, as far as possible, with nitro-muriatic acid, con, taining an excess of muriatic acid, and slightly dihited witli water. The solution is precipitated by the addition of sal-am> moniac, which throws down nearly the whole of the platinum in the state of an ammonio-chloride, which is washed with q little cold water , dried, and heated to redness ; the product ig spongy metallic platinum. This is made into a thin uniform paste with water, pressed in a brass mould, to squeeze oiat the water and render the mass sufficiently solid to bear handling. It is then dried, carefully heated to whiteness, and hammered or jiressed in the heated state ; after this treatment it may be rolled into plates or worked into any desired shape. Phithidteil Asbestos. — Dip asbestos in a solution of chloride of platinum, and heat it to redness. It causes the in- flammation of hydrogen in the same manner as spongy platinum. Platinum-Black. Platina Jlolir. — This is platinum in a finely divided state, and is obtained thus: Add to a solu- tion of bichloride of platinum, an excess of carbonate of soda, and a qiiantity of sugar. Boil until the precipitate which forms becomes, after a little while, perfectly black, and the sui)erna- tant liquid colorli;ss ; filter the powder, 'wash, anddrj'itbya gentle heat. Another method is by melting platina ore with twice its weight of zinc, powdering, digesting first in dihate sul- phuric acid, and next in dilute nitric acid, to remove the zinc, assisting the action of the menstruum by heat; it is then digest- ed ill potash lye, and lastly in pure water, after which it is care- fully dried. Platinum-black possesses the projierty of condens- ing gases, more especially oxygen, into its i^ores, and afterward yielding it to varioxis oxidizable substances. If some of it be mixed with alcohol into a paste, and spread on a watch glass, pure acetic acid is given off, and affords a ready means of diffus- ing the odor of vinegar in an apartment. Testa for Antinnmif. — An acid solution of antimony gives, in combinatinn witli sulj)hureted hydrogen, an orange-red pre- ci2)italc, sparingly soluble in ammonia, but readily solu])le in pure potassa and alkaline sulpliurcts. Ilydrosulpliuret of am- monia throws down from the aci 1 solution an orangr-red pre- cipitate, readily soluble in excess of the i)recipitant, if the latter contain sulphur in excess; and the licpior containing the rc-dis- Bolv(;d i)recipitato gives a yellow or orange-yellow i)recipitate on the addition of an acid. Ammonia, and ])otassa, and their car- bonat(!S (except in solutions of tartar emetic) give a bulky white precipitate; tliat from ammonia bfing insoluble in excess of the precipitant ; that from ])otassa readily so; while those from the carbonate are only soluble on tlio application of heat. T'o ohfain Connmrrial ^i ntinionif. Yniw together KM) jiarts siili)liunt of antimony, -ID jiarts metallic inui, and 10 ]>art8 flry crude Kulpliatd of soda. Tiiis jiroducs from (iO to Ci parts of antimony, besides the scorim or ash, which is also valuable. PRACTICAL MECHANICAL RECEIPTS. 269 Spoiigij Platinnni — Dissolve sejiarately crude bichloride of platinum, and hydrochlorate of ammonia in proof spirit; add the one solution to the other as long as a precipitate falls; this is collected, and, while still moist, formed into little balls or pieces, ■which are then dried, and gradually heated to redness. Sponfjy Platinum. — Dissolve platinum, by the aid of heat, in a mixture of 3 parts nitric and 5 parts muriatic acid, avoiding great excess of acid. To this solution add a strong solution of muriate of ammonia; collect the resiilting i:)recipitate on a filter, and, when nearly dry, form it into a mass of the shape desired for the siDonge. Heat this to whiteness on charcoal, with a blow- pipe or otherwise, and the platinum remains in the spongy state. Its characteristic properties may be restored, when lost, by simply heating it to redness. To purify BifuniifJi. — Dissolve crude bismuth in nitric acid, and concentrate the solution by evaporation. Then pour the clear solution into a large bulk of distilled water, and a white powder (sub-nitrate of bismuth) will be precipitated. Col- lect the precipitate and digest it for a time in a little caustic potash, to dissolve away any arsenious acid that may be present; next wash and dry the sub-nitrate; heat it with about one-tenth its weight of charcoal in an earthen crucible, and the pure bis- muth will be found at the bottom of the crucible. To separate maiiiuth front, Lead. — Dissolve the mixed metal in nitric acid; add caustic potash in excess, and the oxides of bismuth and lead will be preciiDitated, but the lead oxide will be at once re-dissolved by the alkali. The oxide of bismuth can then be separated by filtration, washed, and ignited. To obtain 3IetaUic Antimony. — Mix together 16 parts Bulphviret of antimony and 6 parts cream of tartar, both in pow- der; put the mixture, in small quantities at a time, into a vessel heated to redness ; when reaction ceases, fuse the mass, and, after 1-5 minutes, pour it out and separate the metal from the slag. The product is nearly pure. Or : Equal parts of protoxide of antimony and bitartrate of potassa (cream of tartar) ; mix and fuse as above, and poiir the metal into small conical mov;lds. Or: 8 parts sulphuret of antimony, 6 parts cream of tartar, and 3 parts nitre. Treated as above. 'Or: 2 i^arts sulphuret of antimony and 1 part iron filings; cal- cine at a strong heat in a covered crucible. Black Uronzes. —A very dark colored bronze may be ob- tained by using a little sulphureted alkali (sulphuret of ammo- nia is best). The face of the medal is washed over with the solu- tion, which should be dilute, and the medal dried at a gentle heat, and afterward polished with a hard hair brush. Sulphu- reted hydrogen gas is sometimes employed to give this black bronze, but the efifect of it is not so good, and the gas is very deleterioiis when breathed. In these bronzes the surlace of the copper is converted into a sulphuret. 270 PRACTICAL MECHANICAL RECEIPTS. NageVs Method of Elect t'o plating irith Nickel. — A process devised by Mr. Nagel, of Hamburg, for coating iron, steel, and other oxidizable metals with an electro-deposit of nickel or cobalt, consists in taking 4 parts, by weight, of pure sulphate of the protoxide of nickel by crystallization, and 2 parts, by weight, of pure ammonia, so as to form a doiible salt, which is then dissolved in 60 parts of distilled water, and 12 parts of ammoniacal solution of the sjiecific gravity of .909 added. The electro-deposit is effected by an ordinary galvanic current, using a platiniim positive pole, the solution being heated to about lOO'^ Fahr. The strength of the galvanic current is regii- lated according to the number of objects to be coated. Antique Brotize Coloring. — To impart a brass or an- tique bronze color, either of the three following means may be adopted : A solution of copper, with some acetic acid. Or : The means before described for copi^er color, with a large proportion of liquid ammonia. Or : Water acidulated with nitric acid, by which beautiful bluish shades may be produced. It must be observed, however, this last process can only be properly em- ployed on the alloys which contain a jiortion of copper. To pi'ep((re a JJrass Solution. — For each gallon of water used to make the solution, take 1 part carbonate of ammo- nia, 1 pound cyanide of potassium, 2 ounces cyanide of cojiper, and 1 ounce cyanide of zinc. This constitutes the solution for the decomi)osing cell. It may bo prepared, also from the above proportions of carbonate of ammonia and cyanide of potassium, by immersing in it a large sheet of brass of the desired quality, and making it the anode or positive electrode of a i)Owerful galvanic battery or magneto-electric machine ; and making a small piece of metal the cathode or negative electrode, from which hydrogen must be freely evolved. This ojicration is con- tinued till the solution has taken up a sufficient quantity of the brass to produce a regulino deposit. To electroplate ■ivith JBrass. — For wrought or fancy work, about 15u" Fahr. will give excellent results. The galvanic battery, or magneto-electric jnachine, must be capabhi of evolv- ing hydrogen Irccily from the cathode or negative electrode, or article attached thereto. It is preferred to have a largo anode or l)ositivo electrode, as this favors the evolution of hydrogen. The article or articles treated as before described will immediate- ly become coated with brass. By continuing the process, any desired thickness may be oljtaincd. Should the coi)j)('r have a tendency to come down in a greater proportion than is desired, which may ])e known by the deposit assuming too red an ap- pearanct^ it is corrected bv the addition of carljonate of ammo- nia, or by ft rciduction of temp(!rature when tin; solution is heitful. Should tlie zinc have a tendency to come down in too great a proportion, wliich may be seen l)y the dejxjsit being too ])ale in its a|)|)eiiniiHM!, this is competed by the addition of cya- nide of liotassium or by aa iucreaso of tomiJcrature. PRACTICAL MECHANICAL RECEIPTS. 271 To protect Steel from rusting. — It has been found by experiment that an electro-deposited coating of nickel protects the surface of polished steel completely from rust. Swords, knives, and other articles of steel liable to exposure, may be coated with nickel without materially altering the color of the metal. To electro [date with Qervian Silver. — The alloy, German silver, is deposited by means of a solution consisting of carbonate of ammonia and cyanide of potassium (in the propor- tions given above for the brass), and cyanides or other com- pounds of nickel, cojiper, and zinc, in the requisite proportions to constitute German silver. If is, however, preferred to make the solution by means of the galvanic battery or magneto-electric machine, as above described for brass. Should the copper of the German silver come down in too great a proportion, this is cor- rected by adding carbonate of ammonia, which brings down the zinc more freely ; and should it be necessary to bring down the copper in greater quantity, cyanide of potassium is added — such treatment being similar to that of the brass before described. Brown Bronzes for Medals, aste on the face of the medal, which must then be put into an oven, or laid on an iron jDlate over a slow fire ; when the paste is perfectly reduced to jjowder, brush it off and lay on another coating' ; at the same time quicken the fire, tak- ing care that the additional heat is uniform ; as soon as the sec- ond a^jplication of paste is thoroughly dried, briish it off. The medal being now effectually secured from grease, which often occasions failures in bronzing, coat it a third time, but add to the strength of the fire, and sustain the heat for a considerable time ; a little experience will soon enable the operator to decide when the medal may be withdrawn ; the third coating being removed, the surface will present a beautiful brown bronze. If the bronze is deemed too light the process can be repeated. To bronze Porcelain, Stoneware, and Composition Picture- Frames. — A bronzing process, applicable to porce- lain, stoneware, and composition picture and looking-glass frames, is performed as follows : The articles are first done over with a thin solution of water-glass by the aid of a soft brush. Bronze powder is then dusted on, and any excess not adherent is knocked off by a few gentle taps. The article is next heated, to dry the silicate, and the bronze becomes firmlj' attached. Probably, in the case of porcelain, biscuit, or stoneware, some chemical union of the silicate will take place, but in other cases the water-glass will only tend to make the bronze powder adhere to the surface. After the heating, the bronze may be jjolished or burnished with agate tools. Browning for Gu)i-I>arrCiS.—^lix 1 ounce each aqua- fortis and sweet spirits of nitre ; 4 ounces jjowdered blue vitriol ; 2 ounces tincture of iron, and water, 1 i pints ; agitate until dis- solved. Or : Blue vitriol and sweet sjiirits of nitre, of each 1 ounce ; water, 1 pint ; dissolve as last. Or : Mix equal i)arts of butter of antimony and sweet oil, and apply the mixture to the iron previously warmed. To brown Gun-SarreJs.— The gun-barrel to be browned must be first polished and then rubbed with whiting to remove all oily matter. Its two ends should be stopped with wooden rods, which serve as handles, and the touch-hole filled with wax. Then rub on above solution with a linen rag or sponge till the whole surface is equally moistened. Let it remain till the next day, then rub it off with a stiff brush. The liquid may be again applied until a proper color is produced. When this is the case, wash in pearlash water, and afterward in clean water, and then polish, either with the burnisher or with bees-wax ; or apply a coat of shellac varnish. Bclffian BiirnisJiitif/ Powder. — A burnishing powder in use in Belgium is composed of i pound fine chalk, 3 ounces pipe clay, 2 otinces white lead, J ounce magnesia (carbonate), and the same quantity of jeweller's rouge, 12* 274 PRACTICAL MECHANICAL RECEIPTS. Drab Bronze for Brciss. — Brass obtains a very beautiful drab bronze by being worked in moulders' damp sand for a short' time and brushed up. To protect Silver-Ware from tarnishing.— The loss of silver which results from the impregnation of our atmosphere with sulphur comi)ounds, especially where gas is burned, is very great. Silversmiths may thank one of their confraternity — ]Mr. Strolberger, of Munich — for a happy thought. He seems to have tried various jilans to save his silver, if possible. He covered his goods with a clear white varnish, but foiind that it soon turned yellow in the window, and sjioiled the look of his wares. Then he tried water-glass (solution of silicate of potash), but this did not answer. He tried some other solutions, to no purpose ; but at last he hit upon the expedient of coating his goods over with a thin coating of collodion, which he found to answer per- fectly. No more loss of silver, and no longer incessant labor in keeping it clean. The plan lie adopts is this : He first warms the articles to be coated, and then paints them over carefully with a thinnish collodion diluted with alcohol, using a wide soft brush for the i)urpose. Generally, he says, it is not advisable to do them over more than once. Silver poods, ho tells us, protected in this way, have been exposed in his window more than a year, and are as bright as ever, while others unprotected have become perfectly black in a few months. To prevent Coins and small Ornaments from tarnisUiiKJ. — All ornaments, whether gold or silver, can ^be kept fro u tarnishing if they are carefully covered from the air in box-wood sawdust, which will also dry them after being washed. The tarnish on silver-ware is most often duo to sulphur. A gen- tleman who wears a silver watcih finds that it is tarnished from the sulphur fumes of the rubber ring which holds together his ferry tickets. Sulphur fumes enough get into the air to account for all ordinary cases of tarnishing. To clean /S'eir^/*. -Immerse for half an hour the silver arti- cle into a solution made of 1 gallon water, 1 jiound hyposiilphite of soda, 8 ounec!S niuriiite of aiiiinonia, 4 ounces li(piid ammonia, and 1 ounces cyanide of ])otassium ; but, as the latter substance is poisonous, it can be dispcmsed with if necessary. The article, being taken out of the solution, is washed, and rubbed with a wash-leath(!r. To rlean Silrer-l*lper.— Copper maybe sepa- rated from zinc by sulphuretei hydrogen, which will throw down a sulphuret of copper, which may be dissolved in nitric acid, and treated as in last receipt. To separate Silver from Cojjper.—Bigest, in a state of fiUngs or powder, in a solution of chloride of zinc, which dis- solves the copper and leaves the silver unchanged. To separate Copper from its Alloys.— Coyy-pev may be separated in absolute purity from antimony, arsenic, bismuth, lead, iron, &c., as it exists in bell-metal, brass, bronze, and other commercial alloys, by fusin.;, for about half an hour, in a cru- cible, 10 parts of the metal with 1 part each of copper scales (black oxide) and bottle glass. The pure copper is found at the bottom of the crucible, whilst the other metals or impurities are either volatilized or dissolved in the flux. Reduction of Copper in Fine Powder.— M. Schiff gives the following process for obtaining copper in a state of fine division : A saturated solution of sulphate of copper, together with some crystals of the salt, are introduced into a bottle or flask, and agitated with some granulated zinc. The zinc dis- places the copper from its solution, fresh sulphate dissolving as the action goes on, until the whole is exhausted. Heat is disen- gaged during the operation. The vrccipitated copper must be washed and dried as rapidly as possible, to prevent oxidation. Feather- Sliot Copper.— Melted copper, poured in a small stream into cold water. It forms small pieces, with a feathered edge, hence the name. It is used to make solution of copper. 276 PfiACTICAL MECHANICAL RECEIPTS. Copper ill Fine Powder.— X solution of sulphate of copijer is heated to the boiling-point, and precipitated with sub- limated zinc. The precipitated copper is then separated from the adherent zinc b}' diluted sulphuric acid, and dried by expo- sure to a moderate temperature. BlaeU Enamels.— I. Pure claj-, 3 parts; protoxide of iron, 1 part; mix and fuse. A line black. n. Calcined iron (protoxide), 12 parts; oxide of cobalt, 1 part; mix, and add an equal weight of white flux. III. Peroxide of manganese, 3 parts; zaffre, 1 part; mix and add it as required to white flux. Zaffre is crude oxide of cobalt. Blue Enamels.— I. Either of the white fluxes colored with oxide of cobalt. IL Sand, red-lead, and nitre, of each 10 jiarts; flint glass or ground flints, 2) parts; oxide of cobalt, 1 part, more or less, the quantity depending on the depth of color required. Brown Enumels. — I. Red-lead and calcined iron, of each 1 part; antimony, litharge, and sand, of each, 2 parts; mix and add it in any required proportion to a flux, according to the color desired. A little oxide of cobalt or zaffre is frequently add- ed, and alters the shade of brown. II. Manganese, 5 parts; red-lead, 16 parts; flint powder, 8 parts; mix. III. Manganese, 9 parts; red-lead, 34 parts; flint powder, IG parts. Green Etuiniels. — I. Flux, 2 pounds; black oxide of cop- per, 1 ounce; red oxide of iron, \ dram; mix. IL As above, but use the red oxide of coi)per. Less decisive. IIL Copper dust and litharge, of each 2 ounces; nitre, 1 oz. ; Band, 4 oz. ; flux, as much as required. IV. Add oxide of chrome to a sufficient quantity of flux to pro- duce the desired shade; when well managed the color is superb, and will stand a very great heat; but in careless hands, it fre- quently turns on the dead-leaf tinge. V. Transparent flux, 5 ounces; black oxide of copper, 2 scru- ples; oxide of chrome, 2 grains. Kesembles the emerald. YI. Mix blue and yellow enamel in the required proportions. Orange Enamels. — I. Pied-lead, 12 parts; red sulphate of iron and oxide of antimony, of each 1 part; flint powder, 3 parts; calcine, powder, and melt with flux, .00 parts. II. lied-lead, 12 parts; oxide of antimony, 4 parts; flint pow- der, 3 parts; red sulphate of iron, 1 part; calcine, then add flux, 5 parts to every 2 parts of this mixture. Jlehol. Flujc for solderir.ff Steel.— This answers perfectly when the fracture is an old one. To a saturated solution of zinc in 1 pint muriatic acid, add -i ounces pulverized sal-ammoniac ; boil it for ID minutes; put it, when cold, in a well-corked bottle. The boiling must be done in a copper vessel. Flu.r for fiolderinff Pewter.— Ve-vrtev requires a flux of oil, and may, in addition to the soldering-iron process, be solder- ed by a current of heated air. 2T8 PRACTICAL MSCIIANICAL RECEIPTS. Soft Soldcring.—The solder is an alloy of 2 parts tin to I part lead, fusible at ;J-40° Fahr. ; or, for cheapness, the proportion is sometimes 3 to 2, fusil. le at SI:*-!'. This substance is applied T/ith a hot copper tool called a soldering-iron, or by blow-pipe flame. H^^^'at, however, causes the edges of the metal to oxidize; therefore the edges are cov^ered with a substance having a strong attraction for oxygen, and disposing the metal to unite to the solder at a low temperature. Such substances are called fluxes, and are chiefly borax, resin, sal-ammoniac, muriate of zinc, Venice turpentine, tallow, or oil. Flax pn' soUlei'inff Srass. — For brass or other similar alloy, resin, sal-ammoniac, and muriate of zinc are the projjer fluxes. Should the work be heavy and thick, the soldering re- quires to be done over a charcoal Are in orp(irtioii is not e(pial jjarts. The alloy is heated over a char- coal fire, and brnkfMi to granulations in an iron mortar. .\ dilfer- ent proportifin is used for soldering (topper and inui, viz: 3 zino to 1 coppiT. The (vuumiircial name is " spelter solder." Solder for Oohl. Take 12 parts pure gold, 2 parta pure silver, und 2 parts copper. PRACTICAL MECHANICAL RECEIPTS. 279 Flux for Spelter Solder. — The fliix employed for spelter solder is borax, which can either be used separatelj', or mixed, by- rubbing to a cream, or mixed with the solder in a very little water. To UKlhe Solder. — The mixture of the metals is performed by melting them together in the same manner as for alloys, ■with the aid of a flux. The metals employed should be pure, especially silver, as silver coin makes the solder too hard. Solder for Silver. — Take 5 parts pure silver- not silver coin— 6 parts brass, and 2 parts zinc. Or. 2 parts silver, 1 part common pins. This is an easy flowing solder. Use a gas jet to solder with. Sard Solder. — Take 2 parts copper and 1 part zinc. Or, equal parts of copper and zinc. Solder for Silver. — Take 19 parts fine silver, 1 part copper, and 10 parts brass. Silver Solder. — Melt together .31 parts, by weight, silver coin, and 5 parts copper ; after cooling a little, drop into the mixture 4 parts zinc, then heat again. Fine Silver Solder.-— 'Sldt in a clean crucible, 19 parts pure silver, 10 parts brass, and i i^art coi:)per; add a small piece of borax as a flux. Solder for Cojiper-Same as hard soldering. Solder for Ttii.— Take 4 parts pewter, 1 part tin, and 1 part bismuth. Use powdered rfsin when soldering. To give Bra.'^s an Oranffc Tint.—kn orange tint, in- clining to gold, is produced by first polishing the I rass and then plunging it for a few seconds into a neutral solution of crystal- lized acetate of copper, care being taken that the solution is'com- pletely destitute of all free acid, and possesses a warm tempera- ture To rnhtr Jirass Tlolef. — A beautiful violet is obtained by immersing the polished brass for a single instant in a solution of chloride of antimony, and rubbing it with a stick covered with cotton. The temieruture of the brass at the time the operation is in progress hivs a great influence upon the beauty and delicacy of the tint; in tliis instance it should be heated to a degree so as just to be tolerable to the touch. To give Jirass a Moire Appeara nee. ~A moire appear- ance, vastly superior to that usually seen, is produced by boiling the object in a solution of sulphate of copper. According to the proportions observed between the zinc and the copper in the composition of the brass, so will the tints obtained vary. Ui many instunces it requires the employment of a slight degree of friction, with a resinous or waxy varnish, to bring out the wavy appearance characteristic of moire, which is also singiilarly en- }|i- need by dropping a few iron nails into the bath. IISTIDEIX:. AridDipjyinf/, for brass, 256. Tinning, for brass, 257. Air-pu!np, 183. Alloys for bronze, 210. For copper and zinc, 210. Fusible, 229, 244 Nickel and copper, 227. Platinum and copper, 220. Table of. 209. Aluminnni solder, 230. To frosl, 2G7. Amalgam of gold, 231. Annealing, 217. Antimony, to estimate purity of, 2(i7. Tests for, 268. Metallic, 269. Antimonoid, 233. Autiijue bronze coloring, 270. .\re,is of circles, 5 Argentam, white, 245. Bihhift Mf'tfil, 211. Anti-attrition, 207. Lining bf)xes with, 212. B.dls, copper, brass, cast iron, etc., 97. Barrel, dimensions of a, 36 Jiath metal, 2'J6. Beams, strength of 103, 104, 105, 113 Belgian burnishing powdrr,2^3. Belting, 42. Cal(!iilating horse-power of, 46 Cement for, 220. New, 43. Power of. 42. llules for finding length of 46. Tightcnnrs. 45. To measure a coil of 46. To tost (juality of, 44. Vorticul double leather, 44. Bell-metal, 227, 213. l^ismuth, 269. Bismuth, to separate, fro:u 1 a 1, 269. Black coating for metals, 266. Black enamels, 276. JJlanched copper, 250. Blue enamels, 276. Boilers, 197. Bursting pressure, 203. Consumption of fuel, 202. Draught 197. Fire and flue surface, 20X Flues, 198. Guarding against "incrusta- tion, 214, 234. lloatiug surface, 199, 201 Steam room, 201. Stay bolts 204. Tubes, weight of, 90 Booth's grease for 11. R axles, 255. Borax, substitute for. 211. Brass, for buttons, 225. Cleaning 211. Dark, for castings, 225. Deep yellow malleable, 225. For gilding, 225. For turning, 226. For wire 226. Lacfjuer for, 265. Liglit yellow, 225, 242. Olive bronze, dp for, 255. Poli.shing, 211, 218. lied, 225, 242. Solution to |)re])ar(^ 270. Solder for brazing, 229. Tinning 255. 'i'liat will exjiand, 226. To color, violet, 279. To give, a moirti iii)pearance, 279. To give, an oriingo tint, 279. INDEX. 281 Brass, to harden and soften, 22G. Weiglit of, 94, 9G. Work, to lacquer, 264. To prepare, for dipping, 257. Breast-wheels, 162. Bricks, table of, 28. Ked wash for, 261. Bricklayers' work, 27. Bridges, 108. Bright polish, 251. Britannia metal, 24*^, 256. Hardening for, 243. Bronze, 255. Antique, 240. Alloys for, 210. Black, 269, 272. Brown, for medals, 271. Chinese, 271. Dip for brass, 255. Fine green, 238. Fontainemoreau's, 228 For brass, 239. For cannon, 244. For copi^er, 240. For gun-barrels. 255. For iron castings, 241. For medals, 244. French, 240. Green, for busts, 239. Liquids for tin, 240. Metal, 243. Moire. 210. Paint for copper vessels, 25"). Phosphor, 227. Powder, red, 241. Statuary, 244. Surface, 241. To clean, 227. Bronzing with bleaching pow- der, 240. Brass black, 271. Porcelain, stone-ware, etc. , 273. Surface, 241. With crocus, 273. Wood, 272. Browning for gun-barrels, 273. Brown tint for iron or steel, 213. Burden's spikes and horseshoes, 95. Carpenters' and fToiners' Work, 30. Partitions, staircases, etc., 31. Joists, girders, and flooring, 30. Calculating speed, 157. Cannon, bronze 244. Capacity of cans, 25. Case-hardening, 2i)8, 212, 213, 222, 223. Moxon's method, 223. Polished iron, 222. Small articles, 223. With charcoal, 223. Casks, gauging of, 36. Capacities of, 37. Ullage of, 38. Castings, to bronze, 241. To fill holes in, 211. To find the weight of, 209. Shrinkage of, 146. Cast iron, to bronze, 213. Cement, 254. To .scour, 214. To deposit copper on, 236. To compute the weight of, 93. Weight of flat, 97. Weight of sq. and round, 98. Pipes, weight of, 91. Cast steel, 215. Cement cloth to polished metal, 221. Cast iron, 254. Gutta-percha, 221, 232. Gas retorts, 220. Coating acid troughs, 222. Gutta-percha and leather, 222. Cracks in wood, 221. Roman, 264. Leather belting, 220. Masons', 261. Metal to leather, 220. Portland, 262. Metal letters and glass, 233. Steam-pipe joints, 255. Soft and hard, 244. Water-proof mastic, 261. Centre of gyration, 177. Centrifugal force, 178. Chains, weight and strength i, 101. Charcoal, 41. 282 INDEX. Cliinese silver, 24j. White copper, 256. Circles, diameters, circumfer- ences, and areas of, 5. Coarse stuti" for plastering, 2G3. Cock metal, 213. Cohesive power of metals, 113. Coin of United States, 251. Great Britain, 251. Coins, to protect, from tarnish- ing, 271. Cold tinning, 237. Columns, 117, 118, 181. Common pewter, 251. • Compression of li(piids, 109. Commercial antimony, 2G8. Composition for welding steel, 207, 231. For ornaments, 2G3. Concretes, 12C, 2G3. Concrete floors and walks, 2G3. Cone, contents in gallons of, 9. Cones, 10. Copper, weight of, 96. Blanched, 250. Dimensions of 95. To compute tlie weight of, 93. To separate from alloys, 275. To clean, 218 Reduction to powder, 275. To prevent corrosion of, 218. Feather-shot, 275. Alloys for, 210. riatcs. to coat with brass, 235. Separating silver from, 25(i. Vessels, to coat inside, 235. Vessels, to tin, 23(1. Cu]>ola furnace, 18. Cutting screws, 159. Cylinder, 11. Area of, 187. Diameter of, 182. Det'Aituil Kquivali'iifs of a gallon, 11. D. To protect steel from, 271. Screw Ciitfim/, 159. Scale in boilers, 214, 234. Seals and stamps, 216. Separating silver from copper, 256. Tin from copper, 274. Lead from copper, 275. Sheet iron, weight of, 158. Weight of, galvanized, 100. Ship spikes, 1)4. Shrinkage of castings, 146. Silverware, to protect, from tar- nishing, 274. Silver, German, 243. Coin of U. S., 54. " " Great Britain, 254. Colored metal, 243. Cleaning, 274. Imitation, 213. ' Silvering by heat, 255. Slates, table of domestic, 31. Imported, 33. Slaters' work, 32. Solder, tinman's, 254. Gray cast iron, 22'J. To make, 27'J. Soft, 278. For silver, 279. " gold, 278. " copper. 279. •' tin, 271). Hard. 256, 278, 279. Soldering fluid. 2'i7 277. For soft sf)ldor 277. For iron, cojuxir, and brass, 230. Flux fnr, 277. For aluminum, 230. Noutrul, 277. Solid columns, 115. Solvent for gold. 255. Spanish tutania, 244. Specific gravity, 16 <. Speculum metal, 227, 25ft. Spcmgv platinum, 269. Stain, "black, 246, 247. French i^olish, 251. Mahogany, 246, 247. Standard French polish, 250. Statuary bronze, 244. Steel, annealing, 217. Blueing, 216, 219. Composition for welding, 207. Cast to make, 216. Hardening, 223. Remove scale from, 216. Restoring burnt, 211, 212, 219. Softening, 211. Toughening. 211. Made from iron scraps, 215. Shear, to make, 216. Tempering, 219. " springs. 216. Straightening hardened. 217. To protect from rust, 225, 271. Weight of, 96. Writing on, 220. Steam and steam-engine, 182. Areas of cylinders, 187. Computing lap of valves, 193, lead " 194. " stroke " 195. Circumference of driving wheels, 184. Cylinder, condenser, and air- pump, 183. Diameters of cylinders, 182. Dimensions of a, locomotive, 188. Hyperbolic logarithms, 184. Nniiiiiial power of, 182. Bower of steaiu, 196. I'ressure of steam, 191. Revolution of drivers, 190. Slide valves, 192. Steaui pipe joints, cement for, 255. Travel of valves, 18f>. Throw of eccentrics, 186. Velocity of ])istons, 1H5. Water for injections, 183. IXDEX. 287 Strength of materials, 101. Bar of iron, 108. Beams, lOG, 103, 113. 11^. Bridges, floors, and roofs, lOJ. Cast and malleable iron, 113. Cast iron beams, 105. " " girders, 135. Concretes, cements, etc., 126. Cohesive power of bars, 113. Copper, 12i. Detrusive strength, 139. Dimensions of bars, 131. Floors, beams, girders, itc, 133. Girders, beams, &c., 129. Hollow columns, 117. Lateral pressure, 102. Materials of construction, 102. Models, 110. Resistance of torsion, 108. " bodies, 105. Kectangiilar beams, 104 Eound columns, 118. Shafts and gudgeons, 140. Solid columns, 115. Transverse, 124, 129. Tensile, 119, 121, 123. Torsional, 107, 137. Stucco, Higgins', 261. For inside walls, 262. Square rolled iron, weight of, 90. Square vessel, contents of, 9. Substitute for borax, 211. Tempering, 208, 219. By thermometer, 208. Drills, 219. Gravers, 219. liles, 219. Tempering liquids, 211. Spiral springs, 216. Steel. 219. Tensile strength, 55, 119, 121, 123. Throw of eccentrics, 186. Timber, 141. Felling, 142. Impregnation of, 144. Seasoning and preserving, 142. Timber, weight and strength of, 145. Tin, to sepai'ate from copjjer, 274. Tinman's solder, 254. Tinning, 25. Brass, 2j5. Copper tubes, 238. vessels, 230. " brass, and iron, 238. Cold, 237. Iron for soldering, 229. " pots, 237. " without heat, 237. Kustitien's metal for, 25. Moist way, 237. Tin plate, sizes and weight of, 12. Crystallized, 24. Lacquer for, 265, 266. Manufacture of, 22, 23. Quality of, 24. To find the weight of any cast- ing, 209. To joint lead jiiiies, 211. Tombac, red, 226, 243. White, 227. Torsional strength, 107. Transverse strength, 127, 129. Travel of valves, 186. Treasury Dept. whitewash 2j8. Triangles, 15. Turbines, 164. Turner's work, polish for, 252. Tutania, 229, 244, Tutenag, 228. 245. Type metal, 215. UlJar/e of Casks, 37. Undershot wheels, 162. Use of petroleum in turning metals, 228. Valves, Slide, 186, 192, 193, 194, 195. Valuable intoi-est rules, 41. Varnish, 207, 256. Varnish for patterns, 256. Velocity of water, 176. Veneers, to dve, 245. Black, 245. ' Rose color, 246. fi88 INDEX. Veneers, to silver gray, 246. Yellow, 24(). Vessel, contents in gallons of any, 9. Vinegar bronze for brass, 257. Walls, to irliiteu'ush, 2G0. To kalsomine, 259. Walnut, to give a dark surface, 252. "Water, 1C6. Weight of, 11. Power of, 161. Velocity of, 176. Water- proof polish, 251. Water-wheels, 160. Breast, 162. Overshot, 160. Power of, 161. Power of a stream, 161. Eemarks on, 163. . Turbines, 16-t. Undershot, 162. Weight of boiler tubes, 99. Brass, 96. Brass an