None
Capacity of Feed-water Heaters.— The following extract from a letter by W. R. Billings, treasurer of the Tauntcta Locomotive Manufaetur- ng Co., builders of the Wainwright feed-water heater, to Engineering Record, February, 1898, is of interest in showing the relation of the heating surface of a heater to the work done by it: " Closed feed-water heaters are seldom provided with sufficient surface to raise the feed temperature to more than 200°. Tfc« »ate of heat trans- 1084 APPENDIX. mission may be measured by the number of British thermal units which pass through a square foot of tubular surface in one hour for each degree of difference in temperature between the water and the steam. The diffi- culties which attend experiments in this direction can only be appreciated by those who have attempted to make such experiments. Certain results have been reached, however, which point to what appears to be a reasonable . conclusion. One set of experiments made quite recently gave certain results which may be set forth in the table herewith. 5°F 67 B.T.U. 1 Transmitted in one Difference between final tempera- tures of water and fcteam 79 ...114 .. 129 ...139 hour by each sq. ft. of surface for each degree of average difference in temper- atures. " In other words, when the water was brought to within 5° of the temper- ature of the heating medium, heat was transmitted through the tubes at the rate of 67 B.T.U. per square foot for each degree of difference in temperature in one hour. When the amount of water flowing through the heater was so largely increased as to make it impossible to get the water any nearer than within 18° of the temperature of the steam, the heat was transmitted at the rate of 139 B.T.U. per sq. ft. of surface for each degree of difference in temperature in one hour. Note here that even with the rate of transmission as low as 67 B.T.U. the water was still 5° from the temperature of the steam. At what rate would the heat have been transmitted if the water could have been brought to within 2° of the temperature of the steam, or to 210° when the steam is at 212° ? "For commercial purposes feed-water heaters are given a H. P. rating which allows about one-third of a square foot of surface per H.P.— a boiler H.P. being 30 Ibs. of water per hour. If the figures given in the table above are accepted as substantially correct, a heater which is to raise 3000 Ibs. of water per hour from 60° to 207°, using exhaust steam at 212° as a heating medium, should have nearly 84 sq. ft. of heating surface— that is, a 100 H.P. feed- water heater which is to maintain a constant temperature of not less than 207°, with water flowing through it at the rate of 30CO Ibs. per hour, should have nearly a square foot of surface per H.P. That feed-water heaters do not carry this amount of heating surface is well known.'1 THK STEAM-ENGINE. Current Practice in Engine Proportions, 1897 (Compare pages 792 to 817.)— A paper with this title by Prof John H. Barr, in Trans. A. 8. M. E., xviii. 737, gives the results of an examination of the proportions of parts of a great number of single-cylinder engines made by different builders. The engines classed as low speed (L. S.) are Corliss or other long-stroke engines usually making not more than 100 or 125 revs, per min. Those classed as high speed (H. S.) have a stroke generally of 1 to \y% diameters and a speed of 200 to 300 revs, per min. The results are expressed in for- mulas of rational form with empirical coefficients, and are here abridged as follows : Thickness of Shell, L. S. only.— t = CD-+-B; D = diam. of piston in in.; B = 0.3 in. ; C varies from 0.04 to 0.06, mean = 0.05. Flanges and Cylinder-heads.— I to 1.5 times thickness of shell, mean 1.2. Cylinder-head Studs.— No studs less than % in. nor greater than \% in. diam. Least number, 8, for 10 in diam. Average number = 0.7D. Average diam. = D/40 -f J^in. Ports and Pipes. — a = area of port (or pipe) in sq. in. ; A = area of piston, sq. in.; V= mean piston-speed, ft. per miu.; a = AV/C, in which C '— mean velocity of steam through the port or pipe in ft. per min. Ports, H. S. (same ports for steam as for exhaust).— C= 45"0 to 6500, mean 5500. For ordinary piston-speed of 600 ft. per miu. a = KA ; K = .09 to .13, mean .11. Steam-ports, L. S.— C= 5000 to 9000, mean 6800; K= .08 to .10. mean .09. Exhaust-ports, L. S.— C = 4000 to 7000, mean 5500; K = .10 to .125. mean .11. Steam-pipes, H. S.— C = 5800 to 7000, mean 6500. If d = diam. of pipe and D = diam. of piston, d = .29D to .32D. mean .30D. Steam-pipes, L. S.— C = 5000 to 8000, mean 6000; d = .27 to .35D, mean .32P. Exhaust-pipes, H. S.— C = 2500 to 5500, mean 4400; d = .33 to .50D, mean .377). Exhaust-pipes, L. S.— C = 2800 to 4700, mean 3800; d = .35 to .45D, mean AOD. LOCOMOTIVES. 1085 Face of Pistons.— F= face; D = diameter. F = CD. H. S.: C = .30 to .60 mean .46. L. S.: C= .25 to .45, mean .32. Piston-rods. — d = diam. of rod; D = diam. of piston; L = stroke, in.; d = CVDL. H. S.: C=. 12 to .175, mean .145. L. S.: C= .10 to .13, mean .11. Connecting-rods.— H. S. (generally 6 cranks long, rectangular section): b = breadth; h = height of section; L1 = length of connecting-rod; D = diam. of piston; b = C V^L^ C= .043 to .07, mean .057; h = Kb ; K = 2.2 to 4, mean 2.7. L. S. (generally 5 cranks long, circular sections only): C = .082 to .105, mean .092. Cross-head Slides.— Maximum pressure in Ibs. per sq. in. of shoe, due to the vertical component of the force on the connectiug-rod. H. S.: 10.5 to 38, mean 27. L. S : 29 to 33, mean 40. Cross-head Pins.— I = length; d = diam.; projected area = a = dl — CA; A = area of piston; I = Kd. H. S.: C = .06 to .11, mean .08; K = 1 to 2, mean 1.25. L. S.: C— .054 to .10, mean 07; K = 1 to 1.5, mean 1.3. Crank-pin.— HP = horse-power of engine; L= length of stroke; I = length of pin; I = C X HP/L + B\ d = diam. of pin; A = area of piston; dl = KA. H. S.: C - .13 to .46, mean .30; B = 2.5 in.; K = .17 to .44, mean .24. L. S.: C = .4 to .8, mean .6; B = 2 in.; K = .065 to .115, mean .09. Crank-shaft Main Journal,— d = cHP -+- N; d = diam.; I = length; N = revs, per min.; projected area = MA; A — area of piston. H.S.: C — 6.5 to 8.5, mean 7.3; K = 2 to 3, mean 2.2; M = .37 to .70, mean .46. L. S.: C = 6 to 8, mean 6.8; K = 1.7 to 2.1, mean 1.9; M - .46 to .64, mean .56. Piston-speed.— II. S.: 530 to 660, mean 600; L. S.: 500 to 850, mean 600. Weight of Reciprocating Parts (piston, piston-rod, cross-head, and one- half of connecting-rod).— W- CD* -f- LN*; D = diam. of piston ;L = length of stroke, in. ; N = revs per min. H. S. only: C = 1,200,000 to 2,300,000, mean 1,860,000. Belt-surface per I.H.P.— S = CHP+ B; S = product of width of belt in feet by velocity of belt in ft. per min. H. S.: C = 21 to 40 mean 28; B = 1800. L. S.: S = C X HP.; C = 30 to 42, mean = 35. Fly-wheel (H. S. onl.y).— Weight of rim in Ibs.: W = C X HP + D^N*-^ = diam. of wheel in in.; C = 65 X 1010 to 2 X ?012 mean = 12 X 10", or 1,200,000,000,000. Weight of Engine per I.H.P. in Ibs., including fly-wheel.— W - C X H.P. H. S.:'(7 = 100 to 135, mean 115. L. S.: C - 135 to 240, mean 175. Work of Steam-turbines. (See p. 791.)— A300-H.P. De Laval steam- turbine at the 12th Street station of the Edison Electric Illuminating Co. in New York City in April, 1896, showed on a test a steam-consumption of 19.275 Ibs. of steam per electrical H.P. per hour, equivalent to 17.348 Ibs. per brake H.P., assuming an efficiency of the dynamo of 90#. The steam- pressure was 145 Ibs. gauge and the vacuum 26 in. It drove two 100-K.W. dynamos. The turbine-disk was 29.5 in. diameter and its speed 9000 revs. per min. The dynamos were geared doijn to 750 revs. The total equip- ment, including turbine, gearing, and dynamos, occupied a space 13 ft. 3 in. long, 6 ft. 5 in. wide, and 4 ft. 3 in. high. The " Turbinia," a torpedo-boat 100 ft. long, 9 ft. beam, and 44}^ tons displacement, was driven at 31 knots per hour by a Parsons steam-turbine in 1897, developing a calculated I.H.P. of 1576 and a thrust H.P. of 916, the steam-pressure at the engine being 130 Ibs. and at the boilers 200 Ibs. The vacuum was 13J4 Ibs. The revolutions averaged 2100 per minute. The calculated steam-consumption was 15.86 Ibs. per I.H.P. per hour. On another trial the "Turbinia " developed a speed of 32^4 knots. Relative Cost of Different Sizes of Steam-engines. (From catalogue of the Buckeye Engine Co., Part III.) Horse-power .. Cost per H.P, $ 50 20 75 17fc 100 16 1-25 15 150 14J4 200 13J6 250 13 300 12M 350 12.6 400 12.6 500 12.8 600 13H 700 14 800 15 1086' APPENDIX. GEARING. Efficiency of Worm Gearing-. (See also page 898.)— Worm gear- ing as a means of transmitting power, has until recently, generally been looked upon with suspicion, its efficiency being considered necessarily low and its life short. Recent experience, however, indicates that when prop- erly proportioned it is both durable and reasonably efficient. Mr. F. A. Halsey discusses the subject in Am. Machinist, Jan. 13 and 20, 1898. He quotes two formulas for the efficiency of worm gearing due to Prof. John H. Barr : tan a (1 —/tan a) approx tana+/ tai in which E — efficiency ; a = angle of thread, being angle between thread and a line perpendicular to the axis of the worm ; / = coefficient of friction. Eq. (1) applies to the worm thread only, while (2) applies to the worm and step combined, on the assumption that the mean friction radius of the two is equal. Eq. (1) gives a* maximum for E when tan a = 4/1 -f/2 _ / . . . (3) and eq. (2) a maximum when tan a — 4/2 -f- 4/2 — 2 /. ... (4) Using a value .05 for / gives a value for a in (3) of 43° 34' and in (4) a value of 52° 49'. On plotting equations (1) and (2) the curves show the striking influence of the pitch-angle upon the efficiency, and since the lost work is expended in friction and wear, it is plain why worms of low angle should be short-lived and those of high angle long-lived. The following table is taken from Mr. Halsey's plotted curves : RELATION BETWEEN THREAD-ANGLE SPEED AND EFFICIENCY OF WORM GEARS. Velocity of Pitch-line, feet per minute. 5 10 20 30 40 45 Efficiency. 3 5 10 20 40 100 200 35 40 47 52 60 70 76 52 56 62 67 74 82 85 66 69 74 78 83 88 91 73 76 79 83 87 91 92 76 79 82 85 88 91 9-2 77 80 82 86 88 91 92 The experiments of Mr. Wilfred Lewis on worms show a very satisfac- tory correspondence with the theory. Mr. Halsey gives a collection of data comprising 16 worms doing heavy duty and having pitch-angles ranging between 4° 30' and 45°, which show that every worm having an angle above 12° 30' was successful in regard to durability, and every worm below 9° was unsuccessful, the overlapping region being occupied by worms some of which were successful and some unsuccessful. In several cases worms of one pitch-angle had been replaced by worms of a different angle, an increase in the angle leading in every case to better results and a decrease to poorer results. He concludes with the following table from experiments by Mr. James Christie, of the Pencoyd Iron Works, and gives data connecting the load upon the teeth with the pitch-line velocity of the worm : LIMITING SPEEDS AND PRESSURES OF WORM GEARING. Double- Double- Single-thread t iread thread Worm 1" Pitch, Worm 2" Worm 2±" 2| Pitch Diam. Pitch, 2£ Pitch, 4£ Pitch Diam. Pitch Diam. Revolutions per minute 128 06 201 150 272 905 425 390 128 96 201 150 272 905 201 9,35 272 31 P 425 498 Velocity at pitch-line in feet per minute.... .... Limiting pressure in pounds. .. 1700 1300 1100 700 1100 1100 1100 1100 TOO 400 APPROXIMATE HYDRAULIC FORMULA. 1087 APPROXIMATE HYDRAULIC FORMULJG. (The Lombard Governor Co., Boston, Mass.) Head (H) in feet. Pressure (P) in Ibs. per sq. in. Diameter (D) in feet. Area (A) in sq. ft. Quantity (Q) in cubic ft. per second. Time (T) in seconds. Spouting velocity = 8.02 +'H. Time (T,) to acquire spouting velocity in a vertical pipe, or (Ta) in a pipe on an angle (0) from horizontal: Tl = 8.0-2 l/T/ -f- 32.17, Tj = 8.02 yS •*- 32.17 sin 0. Head (H) or pressure (P) which will vent any quantity (0 through a round orifice of any diameter (D) or area (A): H = Q* + 14.1D4, H = £2 -*- 23.754': P _ QS _j_ 34.1D*, P = £2 -*- 55.3.42. Quantity (Q) discharged through a round orifice of any diameter (D) or area (A) under any pressure (P) or under any head (H): $ = VH x 23.75 x A*, Q = \/Hx 14.71 x D*. Diameter (D) or area (A) of a round orifice to vent any quantity (Q) under any head (H) or under any pressure (P): D= 4/g -*- 3.84 l/fl, Z>= 4/$ -1-5.8 VP; ^ = Q -f- 4.89 VS, 4 = Q -f- 7.35 |/P. Time (T) of emptying a vessel of any area (A) through an orifice of any area (a) anywhere in its side: T - .4164 VH + a. Time (T) of lowering a water level from (£f) to (7t) in a tank through an orifice of any area(n) in its side. Area of tank is (^4). T = 0.4 Kinetic energy (K) or foot-pounds in water in a round pipe of any diameter (D) when moving at velocity (F): K = .76 x D2 x L x V. Time-average-pressure (A. P.) in a pipe of any length (L) with water mov- ing at any velocity ( V) • A.P. = 0.1384LF-*- T. Note.— This must not be confused with water-hammer pressure, which is always many times greater than A.P. and for which no simple formula may Area (a) of an orifice to empty a tank of any area (^4) in any time (70 from any head (H): a« T -i- 0.4094 \/H. Area (a) of an orifice to lower water in a tank of area (A) from bead (H) to (7i) in time CT): a= r-*-0.409x4x( 1088 APPENDIX. SPECIFICATIONS FOR TIN AND TERNE PI.ATTE. (Penna. R. R. Co., 1902.) Each sheet must (1) be cut as nearly exact to size ordered as possible, (3) must be rectangular and flat and free from flaws, (3) must double- seam successfully under all circumstances, (4) must show a smooth edge with no sign of fracture when bent through an angle of 180° and flattened down with a wooden mallet, (5) must be so nearly like every other sheet in the shipment, in thickness, uniformity, and amount of coating, that no diffi- culty will arise in the shops due to varying thickness of sheets, and (6) must correspond for the different grades to the figures in the following table : Kind of Coating. Tin Plate. Pure Tin. No. 1 Terne Plate. \i Tin, % Lead. No. 2 Terne Plate. ^4 Tin, % Lead. Amt. of coating per sq. ft. ... Grade 1C . ... weight per sq. ft. 0.0185 Ib. 0.49 0.0364 Ib. 0.51 0.018'? Ib. 0.49 IX '• " " 0.62 0.64 0.62 " IXX .. " " " 0.71 6.73 0.71 " IXXX.. " " " 0.81 0.83 0.81 1 " IXXXX " " " 0.91 0.93 0.91 LIST OP AUTHORITIES QUOTED IN THIS BOOK. When a name is quoted but once or a few times only, the page or pages are given. The names of leading writers of text-books, who are quoted fre- quently, have the word "various'11 affixed in place of the page-number. The list is somewhat incomplete both as to names and page numbers. Abel, F. A., 642 Abendroth & Root Mfg. Co., 197, 198 American Screw Co., 209 Achard, Arthur, 886, 919 Addy, George, 957 Addyston Pipe and Steel Co., 187, 188 Alden, G. I., 979 Alexander, J. S., 629 Allen, Kenneth, 295 Allen, Leicester, 582 Andrews, Thomas, 384 Ansonia Brass and Copper Co., 327 Arnold, Horace L., 959 Ashcroft Mfg. Co., 752, 775 Atkinson, J. J., 532 Babcock, G. H., 524, 933 Babcock & Wilcox Co., 538, 636 Baermann, P. H., 188 Bagshaw, Walter, 952 Bailey, W. H., 943 Baker, Sir Benjamin, 239, 247, 402 Balch, S. W., 898 Baldwin, Wm. J., 541 Ball, Frank H., 751 Barlow, W. H., 384 Barlow, Prof., 288 Barnaby, S. W., 1013 Barnes, D. L., 631, 861, 863 Barrus, Geo. H., 636 Bauer, Chas. A., 207 Bauschinger, Prof., 239 Bazin, M., 563, 587 Beardslee, L. A.. 238, 377 Beaumont, W. W., 979 Becuel, L. A., 644 Begtrup, J., 348 Bennett, P. D., 354 Bernard, M. & E., 830 Birkinbine, John, 605 Bjorling, P., 676 Blaine, R. G., 616, 1039 Blauvelt, W. H., 639, 649 Blechyaden, A., 1015 Bodmer, G. R., 753 Bolland, Simpson, 946 Booth, Wm. H., 926 Box, Thomas, 475 Briggs, Robert, 194, 478, 540, 672 British Board of Trade, 264, 266, 700 Brown, A. G., 723, 724 Brown, E. H.f 888 Brown & Sharpe Mfg. Co., 219, 890 Browne, Ross E., 597 Brush, Chas. B., 560 Buckle, W^5U Buel, Richard H., 606, 834 Buffalo Forge Co., 519, 529 Builders' Iron Foundry, 874 Burr. Wm. A., 565 Burr, Wm. H., 247, 259, 290, 881 Calvert, F. Crace, 886 Calvert & Johnson, 469 Campbell, H. H., 398. 459, 650 Campredon, Louis, 403 Carnegie Steel Co., 177, 272, 277, 391 Carpenter, R. C., 454, 615, 718, etc. Chad wick Lead Works, 201, 615 Chamberlain, P. M., 474 Chance, H. M., 631 Chandler, Chas. F.. 552 Chapman Valve Mig. Co., 198 Chauvenet, S. H., 370 Chase, Chas. P., 812 Chevandier, Eugene, 640 Christie, James, 394 Church, Irving P., 415 Church, Wm. Lee, 784, 1050 Clapp, Geo. H., 397, 403, 651 Clark, Daniel Kinnear, various Clarke, Ed vf in, 740 Claudel,455 Clay, F. W., 291 Clerk, Dugald, 847 Cloud, John W., 351 Codman, J. E., 193 ' Coffey,B. H.,810 Coffin, Freeman C., 293 Coggswell, W. B., 554 Cole, Romaine C,, 329 Coleman, J. J., 470 Cooper, John HM 876, 900 Cooper, Theodore, 262, 263, 859 Cotterill and Slade, 432, 974 Cowles, Eugene H., 329, 831 Cox, A. J., 290 Cox, E. T., 629 Cox, William, 575 Coxe, Eckley B., 632 Craddock, Thomas, 478 Cramp, E. S., 405 Crimp, Santo, 564 Crocker, F. B., 1070 Cummins, Wm. Russell, W* Daelen, R. M., 617 Dagger, John H. J., 829 Daniel, Wm., 492 D'Arcy, 563 Davenport, R. W., 690 1089 1090 LIST OF AUTHORITIES. Deco3ur, P., 000 DeMeritens, A., 386 Denton, James E., 730, 761, 781, 932 Dinsmore, R. E., 963 Dix, Walter S., 208, Dodge Manufacturing Co., 344 Donald, J. T., 235 Donkin, B., Jr., 491, 783 Dudley, Chas. BM 336, 383 Dudley, P. HM 401, 622 Dudley, W. D., 167 Dulong, M.,458, 476 Dunbar, J. H., 796 Durand, Prof., 56 Dwelshauvers-Dery, 663 E-gleston, Thomas, 235, 641 Emery, Chas. E., 603, 613, 820 Engelhardt, F. E., 463 Ellis and Howland, 577 English, Thos., 753 Ericsson, John, 286 Eytelwein, 564 Fairbairn, Sir Wm., 240, 264, 308, 354 Fairley, W., 531, 533 Palkenau, A.,509 Fanning,J.T.,564, 579 Favre and Silbermann, 621 Felton, C. E., 646 Fernow, B. E., 640 Field, C. J., 30, 937 Fitts, James H., 844 Flather, J. J., 961, 964 Flynn, P. JM 463, 559 Foley, Nelson, 700 Forbes, Prof., 1033 Forney, M. N., 855 Forsyth, Wm., 630 Foster, R. J., 651 Francis, J. B., 586, 739, 867 Frazer, Persifor, 624 Freeman, J. R., 581, 584 Frith, A. J., 874 Fulton, John, 637 Ganguillet & Kutter, 565 Gantt, H. L., 406 Garrison, F. L., 326, 831, 400 Garvin Machine Co., 956 Gause, F. T., 500 Gay, Paulin, 966 Gill, J. P., 657 Gilmore, E. ?., 241 G'aisher, 483 Glasgow, A. G., 654 Goodman, John, 934 Gordon, F. W., 689, 740 Gordon, 247 Goss, W. F. M., 863 Graff, Frederick, 385 Graham, W., 950 Grant, George B., 898 Grant, J. J., 960 Grashof, Dr., 284 Gray, J. McFarlane, 661 Gray, J. M., 958 Greene, D. It, 667 Greig and Eyth, 868 Grosseteste, W., 715 Gruner, L., 623 Hadfleld, R. A.,391,409 Halpin, Druitt, 789, 854 Halsey, Fred'k A., 490, 817 Harkness, Wm., 900 Harrison, W. H., 939 Hartig, J., 961 Hartman, John M., 364 Hartnell, Wilson, 348, 818, 838 Hasson, W. F. C., 1047 Hawksley, T., 485, 513, 564 Hazen, H. Allen, 494 Henderson, G. R., 347, 851 Henthorn, J. T., 965 Hering, Carl, 1045 Herschel, Clemens, 583 Hewitt, G. C., 630 Hewitt, Wm., 917 Hildenbrand, Wm., 913 Hill, John W., 17 Hiscox, G. D., 968 Hoadley, John C., 451, 688 Hobart, J. J., 962 Hodgkinson, 246 Holley. Alexander L., 377 Honey, F. R., 47, 52 Hoopes & Townsend, 210 Houston, Edwin J., 1061 Houston & Kennelly, 1058 Howard, James E., 242, 382, 385 Howden, James, 714 Howe, Henry M., 402, 407, 451, 51 fl Howe, Malverd A., 170, 312 Howland, A. 1091 Kirk, A. C., 706 Kirk, Dr., 1004 Kirkaldy, David, 296 Kopp, H. G. C., 472 Kuichling, E., 578 Kutter, 559 Landreth, O. H.,712 Langley, J. W., 409, 410, 412 Lanza, Gaetano, 310, 369, 864, 977 La Rue, Benj. F., 248 Leavitt, E. D., 788 LeChatelier, M.,452 Le Conte, J., 565 Ledoux. M., 981 Leonard, H. Ward, 1027 Leonard, S. H., 686 Lewis, Fred. H., 186, 189, 379 Lewis, I. N., 498 Lewis, Wilfred, 352, 362, 378, 890 Linde, G., 989 Lindenthal, Gustav, 385 Lloyd's Register, 264, 266, 700 Loss, H. V., 306 Love, E. G., 656 Lovett, T. D., 256 Lyne, Lewis F., 718 McBride, James, 974 MacCord, C. W., 898 Macdonald, W. R., 956 Macgovern, E. E., 545 Mackay, W. M., 542, 544 Mahler, M., 633 Main, Chas. T., 590, 780, 790 Mannesmann, L., 332 Manning, Chas. H., 675, 823 Marks, Win. D., 793, 811 Master Car Builders' Assoc., 878 Mattes, W. F., 399 Matthiessen, 1029 Mayer, Alfred M., 468 Mehrtens, G. G., 895, 405 Meier, E. D., 688 Meissner, C. A., 370 Melville. Geo. W., 674 Mendenhall, T.C.,23 Merriman, Mansfield, 241, 260, 282 Metcalf, William, »40, 412 Meyer, J. G. A., 795, 856 Meystre, F. J., 472 Miller, Metcalf & Parkin, 412 Miller, T. Spencer, 344, 927 Mitchell, A. E., 855, 856 Molesworth, Sir G. L., 562, 658 Molyneux and Wood, 736 Moore, Gideon E., 653 Morin, 435, 930, 933 Morison, Geo. S., 381, 393 Morrell, T. T., 407 Morris, Tasker & Co., 196, 196 Mumford, E. R., 1005 Murgue, Daniel, 521 Wagle, A. P., 292, 606, 878 Napier, 474, 669 Nason Mfg. Co., 478, 542 National Pipe Bending Co., 198 Nau, J. B., 367, 409 Newberry, J. S., 624 Newcomb, Simon, 432 New Jersey Steel & Iron Co., 253, 810 Newton, Sir Isaac, 475 Nichol, B. C., 473 Nichols, 285 Norris, R. Van A., 521 Norwalk Iron Works Co., 488, 504 Nystrom, John W., 265 Ordway, Prof., 470 Paret, T. Dunkin, 967 Parker, W., 354 Parsons, H. de B., 361 Passburg, Emil, 466 Pattinson, John, 629 Peclet, M., 471, 478, 731 Pelton Water Wheel Co., 191, 574, 583 Pence, W. D., 294 Pencoyd Iron Works, 179, 232, 868 Pennell, Arthur, 555 Pennsylvania R. R. Co., 307, 375, 899 Philadelphia Engineering Works. 526 Philbrick, P. H., 446 Phillips, W. B., 629 Phoenix Bridge Co., 263 Phoenix Iron Co., 181, 257 Pierce, C. S., 424 Pierce, H. Roelker, C. R., 265 Roney, W. R., 711 Roots, P. H. & F. M.,526 Rose, Joshua, 414, 869, 970 Rothwell, R. P., 637 Rowland, Prof., 456 Royce, Fred. P., 1043 Rudiger, E. A., 671 Russell, S. Bent, 567 Rust and Coolidge, 290 Sabin, A. H., 387 Sadler, S. P.. 639 Saint Yenant, 282 Salom, P. G., 406, 1056 Sandberg, C. P., 384 Saundera, J. L., 544 Saunders, W. L., 505 Scheffler, I. A., 681 Schroter, Prof., 788 Schutte, L.,&Co., 527 Seaton, various Sellers, Coleman, 890, 953. 975 Sellers, Wm., 204 Sharpless, S. P., 311, 639 Shelton, F. H., 653 Shock, W. H., 307 Simpson, 56 Sinclair, Angus, 863 Sloane, T. O'Connor, 1027 Smeaton, Wm., 493 Smith, Chas. A., 537, 874 Smith, C. Shaler, 256, 865 Smith, Hamilton, Jr., 556 Smith, Jesse M., 1050 Smith, J. Bucknall, 225, 303 Smith, Oberlin, 865, 973 Smith, R. H., 962 Smith, Scott A., 874 Snell, Henry L, 514 Stahl, Albert W., 599 Stanwood, J. B,, 802, 809, 813, 818 Stead, J. E., 409 Stearns, Albert, 465 Stein and Schwarz, 410 Stephens, B. F., 292 Stillman, Thos. BM 944 Stockalper, E., 490 Stromeyer,C. E., 395 Struthers, Joseph, 451 Sturtevant, B. F., Co., 487, 578 Stut, J. C. H., 844 Styffe, Knut, 383 Suplee, H. H., 769, 772 Suter, Geo. A., 524 Sweet, John E., 826 Tabor, Harris, 751 Tatham & Bros., 201 Taylor, Fred. W., 880 Taylor, W. J., 646 Theiss, Emil, 818 Thomas, J. W., 369 Thompson, Silvanus P., 1064, 1066 Thomson, Elihu, 1052 Thomson, Sir Wm., 461, 1039 Thurston, R. H., various Tilghman, B. F., 966 Tompkins,C.R.,388 Torrance, H. C., 401 Torrey, Joseph, 582, 820 Tower, Beauchamp, 931, 934 Towne, Henry R., 876, 907, 911 Townsend, David, 973 Trautwine, J. C., 59, 118, 311, 482 Trautwine, J. C., Jr., 255 Trenton Iron Co., 216, 223, 230, 915 Tribe, James, 765 Trotz, E , 453 Trowbridge, John, 467 Trowbridge, W. P., 478, 513, 733 Tuit, J. E., 616 Tweddell, R. H., 619 Tyler, A. H., 940 Uchatius, Gen'l, 321 Unwin, W. Cawthorne, various Urquhart, Thos., 645 U.S. Testing Board, 308 Vacuum Oil Co., 943 Vair, G. O., 950 Violette, M , 640, 642 Vladomiroff, L., 316 Wade, Major, 321, 374 Wailes, J. W., 404 Walker Mfg. Co., 905 Wallis, Philip, 858 Warren Foundry & Mach. Co., 18P Weaver, W. D., 1043 Webber, Samuel, 591, 963 Webber, W. O., 608 Webster, W. Wood, H. A., 9 Wood, M. P., 386, 389 Woodbury, C. J. H., 537, 931 Wootten, J. E., 855 Wright, C. R. Alder, 331 Wright, A.W.,289 Yarrow, A. F., 710 Yarrow & Co., 307 Yates, J. A., 287 Zahner, Robert, 498 Zeuner,827 INDEX. abb-alt Abbreviations, 1 Abscissas, 69 Abrasion of manganese steel, 407 Abrasive processes, 965-967 Absolute temperature, 461 zero, 461 Absorption of gases, 480 of water by brick, 312 refrige rating-machines, 984 Accelerated motion, 427 Acceleration, definition of, 423 force of, 427 work of, 430 Accumulators, electric, 1045-1048 Adiabatic compression of air, 499 curve, 742 expansion of air, 501 expansion in compressed air- engines, 501a expansion of steam, 742 Adiabatically compressed air, mean effective pressures, table, 50 Ib Admiralty metal, composition of, 325 Admittance of alternating cur- rents, 1063 Aiken intensifier, 619 Air, 481-527 and vapor mixture, weight of, ,484. binds in pipes, 579 carbonic acid allowable in, 529 '•> compressed, 498-511 (see Com- pressed air) compressors, effect of intake temperatures, 506 compressors, high altitude, table of, 503 compressors, tables, 503-505 cooling of, 531 density and pressure, 481, 482 flow of, in pipes, 485, 489 flow of, in ventilating ducts, 530 flow of through orifices, 484, 518 friction of, in underground pas- sages, 531 head of, due to temperature dif- ferences, 533 heating of, by compression, 498 horse-power required to com- press, 501 loss of pressure of in pipes, 487 ; tables, 488-490 manometer, 481 properties of, 481 pump for condenser, 841 Air, specific heat of, 458, 484 lift pump, 614 pyrometer, 453 thermometer, 454 velocity of, in pipes, by anemom- eter, 491 volumes, densities, and pressures (table), 481 volume transmitted in pipes, 864 weight of, 165, 481; table, 484 Alcohol, compressibility of, 164 Alden absorption dynamometer, 979 Algebra, 33-36 Algebraic symbols, 1 Alligation, 10 Alloys, 319-338 aluminum, 328 aluminum, tests of, 330 aluminum-antimony, 331 aluminum -copper, 329 aluminum -copper-tin, 330 aluminum -silicon-iron, 330 aluminum -tin, 330 aluminum -tungsten, 330 aluminum -zinc, 330 antimony, 336 bearing metal, 333 bismuth, 332 caution as to strength of, 329 composition of, in brass foundries, 325 composition by mixture and by analysis, 323 copper-manganese, 331 copper-tin, 319, 320 N copper-tin-lead, 326 copper-tin-zinc, 322, 325 copper-zinc, 321 copper-zine-iron, 326 fusible, 333 Japanese, 326 liquation of metals in, 323 nickel, 332 variation in strength of, 323 white metal, 3,36 "Alloy" steels, 407-410 Alternating currents, 1061-1078 admittance, 1063 average, maximum, and effective, values, 1061 m calculation of circuits, 1072 capacity, 1062 capacity of conductors, 1067 converters, 1071 delta connection, 1069 1093 1094 alt-bai INDEX. Alternating currents, frequency, 1061 generators for, 1070 impedance, 1063 impedance polygons, 1064-1066 inductance, 1062 induction motor, 1072, 1077 measurement of power in poly- phase circuits, 1069 Ohm's law applied to, 1064 power factor, 1062 reactance, 1063 single and polyphase, 1068 skin effect, 1063 synchronous motors, 1071, 1076 transformers, 1070 Y connection, 1069 Altitude by barometer, 483 Aluminum, 167, 317 alloys, 319, 328 (see Alloys) alloys, tests of, 330 brass, 329 bronze, 328 bronze wire, 225 electrical conductivity of 1028 solder. 319 steel, 409 strength of. 318 wire, 225 American base-box system, 182 Ammonia-absorption refrigerating- machine, 984, 987 ; test of, 997 Ammonia-compression refrigerat ing- machines, 983, 986; test of, 999 Ammonia gas. properties of, 992 Ammonia liquid, density of, 992 specific heat of, 992 Ampere, 1024 Analyses, asbestos, 235 of boiler scale, 552 of boiler water, 553, 554 of cast iron, 371-374 of coals, 624-632 of coal, sampling for, 632 crucible steel, 411 fire-clay, 234 gas, 651 gases of combustion, 622 magnesite, 235 Analytical geometry. 69-71 Anchor forgings, strength of, 297 Anemometer, 491 Angle, economical, of framed struc- tures. 447 of repose of building material. 929 Angles, Carnegie bulb, properties of, table, 278 Carnegie steel, properties of, table. 27 9a Pencoyd steel, weights and sizes, .179 trigonometrical properties of, 66 plotting without protractor, 52 problems in, 37, 38 Angular velocity, 425 Animal power 433-435 Annealing, effect on conductivity, 1029 effect on steel, 392, 412 influence of on magnetic capac- ity of steel, 396 non-oxidizing process of, 389 of steel, 394, 413 of steel forgings, 396 of structural steel, 394 Annuities, 15-17 Annular gearing, 898 Anthracite, classification of, 624 composition of, 624 sizes of, 632 space occupied by, 625 Anthracite-gas, 647 Anti-friction curve, 50, 939 metals, 932 Antimony, properties of, 167 in alloys, 331, 336 Apothecaries' measure and weight, 18, 19 Arc, circular, 57 circular, Huyghen's approxima- tion of length of, 58; table, 114 circular, relations of. 58 Arc-lights, electric, 1041 Arches, corrugated 181 flooring, 281 tie-rods for, 281 Area of circles 1-1000, table, 103- 107 of circles A-lOO, table advanc- ing by i. 108-112 of geometrical solids, 61-63 of geometrical plane figures, 54-60 of irregular figures, 55, 56 of sphere, 61 of sphere, table, 118 Arithmetic, 2-32 Arithmetical progression, 11 Armature-circuit, e.m.f. of, 1056 Armature torque of, 1056 Asbestos, 235 Asphalt um coating for iron, 387 Asses, work of, 435 Asymptotes of hyperbola, 71 Atmosphere, equivalent pressures of, 27 pressure of , 481 . 482 moisture in 483 Atomic weights (table) 163 Authorities, list of, 1089 Avogadro's law of gases, 479 Avoirdupois weight, 19 Axles, railroad, effect of cold 384 steel, specifications for, 397 steel, strength of, 299 Automatic cut-off engines 753 Babbitt metal. 336, 337 Babcock & Wilcox boilers, testa with various coals, 636 Bagasse as fuel, 643 Balances, to weigh on incorrect, 19, Ball-bearings 940 Balls, hollow copper, 289 IHDEX. baii-boi 1095 Bands and belts, theory of , 876 for carrying grain, 912d Bars, eye, tests of, 304 iron, flat, commercial sizes of, table, 170 iron, various shapes, commer- cial sizes of, 171 Lowmoor iron, strength of, 297 steel, effect of nicking, 402 twisted iron, tensile strength of, 241 twisted , Cilmore's experiments on , 242 various, weights of, 169 wrought iron, compression tests of, 304 wrought iron, weight of, table, 171 Barometer, leveling with, 482 to find altitude by, 483 Barometric readings for various altitudes, 482 Barrels, to find volume of, 64 number of, in tanks, 126 Basic Bessemer steel, strength of, 390 Batteries, storage, 1045-1048 Baume's hydrometer, 165 Bazin's experiments on weirs, 587 formulae, flow of water, 563 Beams, deck, properties of Carne- gie, table, 278 formulae for flexure of, 267 formulae for transverse strength of, 268 special, coefficients for loads on, 270 steel, formulae for safe loads on, 269 variously loaded, 271 yellow pine, safe loads on, 1023, 1079 Beardslee's tests on elevation of elastic limit, 238 Bearings, allowable pressure on, 935-937 ball, 940 cast-iron, 933 for steam turbines, 941 high speed, 941 oil pressure in, 937 overheating of, 938 pivot, 939 roller, 940 steam-engine, 811-813 Bearing-metal alloys, 333 Bearing-metals, anti-friction, 932 composition of, 326 Bearing pressure on rivets, 355 Bed-plates of steam-engines, 817 Bell -metal, composition of, 325 Belt conveyors, 912d dressings. Boiler heads, 706 heads, strength of, 284, 286 heads, wrought-iron, 285 heating-surface for steam heat- ing, 538 scale, analyses of, 552 tubes, area of, table, 197 tubes, dimensions of, table, 196 tubes, expanded, holding power of, 307 Boilers, horse-power, 677 for steam heating, 538 incrustation of, 550 locornotive, 855 marine, 1015 plate, strength of, at high tem- peratures, 383 steam, 677-731 (see Steam-boiler) Boiling, resistance to, 463 Boiling-point of water, 550 Boiling-points of substances, 455 Bolts and nuts, 209, 211 .-•effect of initial strain in, 292 holding power of in white pine, 290, 291 square-head, table of weights of, 210 strength of, table, 292 taper, 972 track, weight of, 210 variation in size of iron for, 206 Bomb calorimeter, 634 Braces, diagonal, with tie, stresses in, 442 Brackets, cast-iron, strength of, 252 Brake, Prony, 978 Brass, composition of rolled, 203 alloys, 325 plates and bars, weight of, table, 202, 203 tube, seamless, table, 198-200 wire, weight of, table, 202 Brazing of aluminum bronze, 328 metal, composition of. 325 solder, composition of, 325 Brick, absorption of water by, 312 for floors. 281 kiln, temperatures in, 452 specific gravity of, 165 strength of, 302, 312 weight of, 165, 312 Bricks, fire, number required for various circles, table, 234 fire, sizes and shapes of, 233 Bricks magnesia, 235 Brickwork, measure of, 169 weight of, 169 Bridge iron, durability of, 385 links, steel, strength of, 298 members, strains in, 262-264 Memphis, proportions of mate- rial. 381 Memphis, tests of steel in. 393 trusses, 442 Brine, boiling of, 463 properties of, 464, 994 Briquettes, coal, 632 British thermal unit (B.T.U.), 455, 660 Britannia metal, composition of, 336 Bronze, aluminum, strength of 328 ancient, composition of, 323 deoxidized, composition of, 327 Gurley's, composition of, 325 manganese. 331 phosphor, 327 strength of, 300, 319, 321 Tobin, 325, 326 Buck-shot, sizes and weights of 204 Buildings, construction of, 1019- 1023 fire-proof. 1020 heating and ventilation of. 534 transmission of heat through walls of, 478 walls of, 1019 Building-laws, New York City, 1019-1021 on columns, New York, 252. 1019 on columns, Boston, 252 on columns, Chicago 252, 255 on structural materials, Chicago, . 3?1 Building-materials, angle of repose of, 929 coefficients of friction of, 929 sizes and weights. 169, 184 Bulb angles, properties of Carne- gie steel, table, 278 Bulkheads, plating and framing for, table, 287 Buoyancy, 550 Burr truss, stresses in, 443 Bushel of coal, 638 of coke, 638 Bush-metal, composition of, 325 Butt-joints, riveted, 358 Cables, chain, wrought-iron, 308, 340 flexible steel wire, 223 sizes, weight, and strength, 230 338 lead-incased power, sizes and weights, 222 suspension -bridge. 230 Cable-ways, suspension. 915 Cadmium, properties of, 167 Calculus, 72-79 Calcium chloride in refrigerating- machines. 994 Caloric engines, 851 Calorie, definition of, 455 Calorimeter for coal, Mahler bomb, 634 steam, 7 28-7 31 steam, coil, 729 steam, separating, 730 steam, throttling 729 Calorimewic tests of coal, 636 INDEX. cam-chi 1097 Cam, 438 Canals, irrigation, 564 speed of vessels on, 1008 Candle-power of electric lights, 1042 of gas lights, 654 Canvas, strength of, 302 Cap-screws, table of standard, 208 Capacity, electrical, 1062 electrical, of conductors, 1067 Car-heating by steam , 538 Car-journals, friction of, 937 Cars, steel plate for, 401 Car-wheels, cast iron for, 375 Carbon, burning out of steel, 402 effect of, on strength of steel, 389 gas, 646 Carbonic acid allowable in air, 529 Carnegie steel sections, properties of, 272T280 steel sections, weights and sizes, 177, 178 t Carriages, resistance of, on roads, 435 Carriers, bucket, 912a Casks, volume of, 64 Cast copper, strength of, 300, 319 Cast iron, 365-376 analyses of, 371-374 bad, 375 bearings, 933 Bessemerized, 375 chemistry of, 370-374 columns, eccentric loading of, 254 columns, strength of, 250-253 columns, tests of, 250, 251 columns, weight of, table, 185 compressive strength of, 245 corrosion of, 386 durability of, 385 influence of phosphorus, sulphur, etc., 365-368, 370 malleable, 375 mixture of, with steel, 375 pipe, 185-190 (see Pipe, cast- iron) pipe-fittings, sizes and weights, 187 relation of chemical composition to fracture, 370 shrinkage of, 368 specific gravity of, 374 specifications for, 374 strength of, 296, 370-374 strength in relation to silicon and cross-section, 369 tests of, 369 variation of density and tenac- ity, 374 Castings, iron, analyses of, 373 iron, strength of, 297 malleable, rules for use of, 376 shrinkage of , 951 steel, 405 steel, specifications for, 397, 406 steel, strength of, 299 weight of, from pattern, 952 Catenary, to plot, 51, 52 Cement as a preservative coating, 387 Cement for leather belts, 887 mortar, strength of, 313 Portland, strength of, 302 specific gravity of, 166 weight of, 166, 170 Center of gravity, 418 of gravity of regular figures, 419 ] of gyration, 420 of oscillation, 421 of percussion, 422 Centigrade thermometer scale, 448 -Fahrenheit conversion table, 449 Centrifugal discharge elevators, 912a fans (see Fans, centrifugal) force, 423 force hi fly-wheels, 820 pumps, 607-609 (see Pumps, centrifugal) tension of belts, 876 C.G.S. Chimneys, steel, 740 steel, foundations for, 741 tall brick, 737 velocity of air in, 733 weak, 739 Chord of circle, 58 Chords of trusses, strains in, 445 Chrome steel, 409 Circle, 57-59 area of, 57 area of, 1-1000, table, 103-107 area of, ^-100, advancing by £, table, 108-112 equations of, 70 length of arc of, 57 length of arc of, Huyghen's ap- proximation, 58 length of chord of, 58 problems, 39, 40 properties of, 57 relations of arc, chord, etc., of, 58 relations of, to equal, inscribed, and circumscribed square, 59 sectors and segments of, 59 Circuits, electric, e.m.f. in, 1030 electric, polyphase, 1068 (see Alternating currents) electric, power of, 1031 Circuit, magnetic, 1051 Circular arcs, lengths of, 57 arcs, lengths of, tables, 114, 115 functions, calculus, 78 inch, 18 measure, 20 mil, 18 mil wire gauge, 30 mil wire gauge, table, 29 pitch, 888 ring, 59 segments, table of areas of, 116 Circumferences of circles, 1-1000, table, 103-107 of circles, ^-100, table, advanc- ing by i, 108-112 of circles, 1 inch to 33 feet, table, 113 Cisterns, capacities of, 121, 126 Classification of iron and steel, 364 Clay, cubic feet per ton, 170 fire, analysis of Mt. Savage, 233 Clearance in steam-engines, 751,792 Coal, analyses of, 624-632 anthracite, sizes of, 632 bituminous, classification of, 623 calorimeteric tests of, 636 classification of, 623-624 conveyors, 912a cost of, for steam power, 789 DuLong's formula for heating, value of, 633 evaporative power of, 636 foreign, analysis of , 631 furnaces for different, 635 heating value of, 633, 634 handling machinery, 912-912d hoisting by rope, 343 products of distillation of, 639, 651 relative value of, 633-637 Coal, sampling of, for analysis, 632 semi-bituminous, composition of, 625, 626 space occupied by anthracite, 625 storage bins, 912a vs. col-con 1099 Columns, wrought -iron, built, 257 wrought -iron, Merriman's table of, 260 wrought -iron, tests of, 305 wrought -iron, ultimate strength of, table, 255 Combination, 10 Combined stresses, 282, 283 Combustion, analyses of gases of, 622 heat of, 456, 621 of fuels, 621 of gases, rise of temperature in, 623 rate of, due to chimneys, 732 theory of, 620 Composition of forces, 415 Compound engines, 761-768 (see Steam-engines, compound) interest, 14 locomotives, 862, 863 numbers, 5 proportion, 6 shapes, steel, 248 units of weights and measures, 27 Compressed-air, 488, 498-511 adiabatic and isothermal com- pression, 499 adiabatic expansion and com- pression, tables, 502 compound compression, 5016 cranes, 912 diagrams, 5016 drills driven by, 506 engines, adiabatic expansion in, 501a engines, efficiency, 506 for motors, effect of heating, 507 flow of, in pipes, 489 formula?, 501 heating of, 498 hoisting engines, 5056 horse-power required to compress air, 500 losses due to heating, 500 loss of energy in, 498 machines, air required to run, 505a mean effective pressures of adiabatically compressed air, table, 5016 mean effective pressures, com- pound compression, table, 5016 mean effective pressures, tables, 502, 503 mine pumps, 511 motors, 507 Popp system, 507 practical applications of, 5056 pumping with, 505a reheating of, 506 shop operation by, 509 tramways, 510. 511 transmission , 488 transmission, efficiencies of, 508 volumes, mean pressures per stroke, etc., table, 499 work of adiabatic compression, 601 Compressed steel, 410 Compression, adiabatic, formulae for, 501 adiabatic, tables, 502 and flexure combined, 282 and shear combined , 282 and torsion combined, 283 in steam-engines, 751 members in structures, unit strains in, 380 Compressive strength, 244-246 strengths of woods, 311 strength of iron bars, 304 tests, specimens for, 245 Compressors, air, 503-505 air, effect of intake temperature, 506 Condensers, 839-846 air-pump for, 841 circulating pump for, 843 continuous use of cooling water in, 844 cooling towers for, 844 cooling water required, 841 ejector, 840 evaporative surface, 844 increase of power due to, 846 jet, 839 surface, 840 tubes and tube plates of, 840. 841 tubes, heat transmission in, 472 Conduction of heat, 468 of heat, external, 469 of heat, internal, 468 Conductivity, electric, of steel, 403 electrical, of metals, 1028 Conductors, electrical, heating of, 1031 electrical, in series or parallel, resistance of, 1030 Conduit, water, efficiency of, 589 Cone, measures of, 61 pulleys, 874 Conic sections, 71 Connecting-rods, steam -engine, 799, 800 tapered, 801 Conoid, parabolic, 63 Conservation of energy, 432 Construction of buildings, 1019- 1023 Convection, loss of heat due to, 476 of heat, 469 of heat, Dulong's law of, table of factors for, 477 Conversion table, Centigrade-Fah- renheit, 449 tables, metric, 23-26 Converter, Bessemer, temperature determinations in, 452 Converters, electric, 1071 Conveying of coal in mines, 913, 914 Conveyors, belt, 912d cable-hoist, 915 coal, 912a horse -power required for, 912c screw, 1100 coo-cyl INDEX. Cooling of air for ventilation, 531 towers for condensers, 844 Co-ordinate axes, 69 Copper, 167 ball pyrometer, 451 cast, strength of, 300, 319 drawn, strength of, 300 balls, hollow, 289 manganese alloys, 331 nickel alloy, 332 plates, strength of, 300 plates, weight pf, table, 202 round bolt, weight of, table, 203 strength of, at high temperatures, 309 tin alloys, 320 tin alloys, properties and compo- sition of, 319 tin-aluminum alloys, 330 tin-zinc alloys, properties and composition, 322, 323 tubing, weight of, table, 200 weight required in different sys- tems of transmission, 1075 wire, table of dimensions, weight, and resistance of 202, 218- .220, 1034 wire, cost of, for long-distance transmission, 1036, 1040 zinc alloys, strength of, 323 zinc alloys, table of composition f and properties, 321 zinc-iron alloys, 326 Cordage, technical terms relating to, 341 weight of, table, 906 Cork, properties of, 316 Corn, weight of, 170 Corrosion of iron, 386 of steam-boilers, 386, 552, 716- 721 Corrosive agents in atmosphere 386 Corrugated arches, 181 furnaces, 266, 702, 709 iron, sizes and weights, 181 plates, properties of Carnegie steel, table, 274 Cosecant of an angle, 65; table, 159- 162 Cosine of an angle, 65; table, 159- 162 Cost of coal for steam-power, 789 of steam-power, 790 Cotangent of an angle, 65; table, 159-162 Cotton ropes, strength of, 301 Couloumb, 1024 Counterbalancing of hoisting-en- gines, 909 of locomotives, 864 of steam-engines, 788 Counterpoise ~ system of hoisting, 910 Couples, 418 Coverings for steam-pipe, tests of, 470, 471 Coversine of angles, table, 159- 162 Cox's formula for loss of head 575 Crane chains, 232 Cranes, 911 classification of, 911 compressed air, 912 electric, 912 jib, 912 stresses in, 440 travelling, 912 guyed, stresses in, 441 simple, stresses in, 440 Cranks, steam-engine, 805 Crank angles, steam-engine, table, 830 pins, steam-engine, 801-804 pins, steel, specifications for, 401 shafts, steam-engine, 813-815 shaft, steam-engine, torsion and flexure of, 814 Cross-head guides, 798 pin, 804 Crucible steel, 410-414 (see Steel, crucible) Crushing strength of masonry mate- rials, 312 Cubature, 75 Cubes of numbers, table, 86-101 of decimals, table, 101 Cube root, 8 roots, table of. cyl-ela 1101 Cylindrical ring, 62 Cylindrical tanks, capacities of, table, 121 Dalton's law of gaseous pressures, 480 Dam, stability of, 417 D'Arcy's formula, flow of water, 563 formula, table from, of flow of water in pipes, 569-572 Decimals, 3 squares and cubes of, 101 Decimal equivalents of fractions, 3 equivalents of feet and inches, 112 gauge, 32 Deck -beams, weights and sizes, 177 properties of Carnegie steel, 278 Delta connection for alternating currents, 1069 metal, 225, 326 Denoniinate numbers, 5 Deoxidized bronze, 327 Derrick, stresses in, 441 Diagonals, formulae for strains in, 444 Diametral pitch, 888 Differential gearing, 898 calculus, 72-79 of algebraic function, 72 of exponential function, 77 partial, 73 coefficient, 73 ; sign of , 76 second, third, etc., 75 pulley, 439 screw, 439; efficiency of, 974 windlass, 439 Differentiation, formulae for, 73 Discount, 13 Disk fans (see Fans, disk) Displacement of ships, 1001, 1008 Distillation of coal, 639 Distiller for marine work, 847 Domes on steam-boilers, 711 Draught power of chimneys, 732 theory of chimneys, 731 Drawing-press, blanks for, 973 Dredge, centrifugal pump as a, 609 Dressings, belt, 887 Drift bolts, resistance of, in timber, 290 Drill gauge, table, 29 press, horse-power required by, 963 Drills, rock, air required for, 505a rock, requirements of air-driven, 506 twist, speed of, 957 tap, 970, 971 ; sizes of, 208 Prilling holes, speed of, 956 machines, electric, 956 Drop in electric circuits, 1029-1031 press, pressures attainable by, 973 Drums for hoisting-ropes, 917 Dry measure, 18 Drying and evaporation, 462-467 in a vacuum, 466 Ducts, cold-air, for steam -heating, 539 Ductility of metals, table, 169 Dulong's formula for heating value of coal, 633 law of convection, table of factors for, 477 law of radiation, table of factors for, 476 Durability of iron, 385, 386 Durand's rule for areas, 56 Dust explosions, 642 fuel, 642 Duty, measure of, 27 of pumping-engine, 610 trials of pumping-engines, 609- 612 Dynamo-electric machines, 1055- 1060 machines, classification of, 1055 machines, design of, 1058- 1060 machines, e.m.f. 