FORMULA.
D2 × .7854 × Stroke
1728 = C.
Example.

Cubic content of a cylinder 15 × 24 is

15 × 15 × 0.7854 × 24
1728 = 2.44 cubic feet.

372. Table 7. Capacity of cylinders in cubic feet of from ten to twenty-four inches in diameter, and from eighteen to thirty-six inches stroke.

Diam. of cyl’r. CAPACITY OF CYLINDERS IN CUBIC FEET, STROKE BEING Diam. of cyl’r.
18 20 22 24 26 28 30 32 34 36
10 082 091 100 109 118 127 136 145     10
11 093 104 115 126 137 148 159 170 181   11
12 118 131 144 157 170 183 196 209 222 235 12
13 133 149 165 181 197 213 229 245 261 277 13
14 160 178 196 214 232 250 268 286 304 322 14
15 184 204 224 244 264 284 304 324 344 364 15
16 208 232 255 278 301 324 347 370 393 416 16
17 235 263 289 315 341 367 393 419 445 471 17
18 263 294 323 352 381 410 439 468 497 526 18
19     361 394 427 460 493 526 559 592 19
20     400 437 474 511 548 585 622 659 20
21       481 521 561 601 641 681 721 21
22       528 572 616 660 704 748 792 22
23         625 674 723 772 821 876 23
24         681 733 785 837 889 941 24

373. Table 8. Giving the volume, pressure, temperature, and density of steam.

Steam pressure. Relative volume or cubic feet of steam, water being 1. Temperature. Total heat. Weight of a cubic foot. Steam pressure.
50 552 281 1200 1129 50
60 467 293 1203 1335 60
65 434 298 1205 1436 65
70 406 303 1206 1535 70
75 381 307 1208 1636 75
80 359 312 1209 1736 80
90 323 320 1212 1929 90
100 293 328 1214 2127 100
110 269 335 1216 2317 110
120 249 341 1218 2505 120
130 231 347 1220 2698 130
140 216 353 1221 2885 140
150 203 358 1223 3070 150
FORMULA.
S =√ac × 21.2.
Where S = surface.
a = grate area.
c = cubic feet of water per hour.
Example.

Grate area sixteen square feet, cubic feet of water per hour two hundred, surface is

√16 × 200 × 21.2 = 1199.92.

374. Table 9. Showing the necessary amount of grate area and heating surface for an hourly consumption of water.

Cubic ft. of water evap’d per hour. GRATE AREAS IN SQUARE FEET.
7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30
HEATING SURFACE CORRESPONDING TO ABOVE GRATE AREAS AND TO SIDE COLUMN.
100 561 599 636 670 703 734 764 793 821 848 874 900 924 948 972 995 1017 1039 1060 1081 1102 1122 1142 1161
110 588 628 667 702 737 770 802 831 861 888 916 943 969 994 1018 1042 1066 1089 1111 1133 1155 1176 1197 1217
120 614 657 697 734 770 805 837 869 900 927 957 985 1013 1039 1064 1089 1114 1138 1162 1184 1207 1229 1251 1272
130 639 683 725 764 801 837 871 904 936 965 996 1025 1053 1081 1107 1133 1159 1184 1208 1232 1255 1278 1300 1323
140 663 709 752 793 831 869 904 938 972 1003 1034 1064 1093 1122 1150 1177 1203 1229 1254 1279 1303 1327 1351 1374
150 686 734 779 821 860 900 935 971 1006 1038 1070 1101 1131 1161 1190 1218 1245 1272 1298 1323 1350 1373 1398 1422
160   758 805 848 889 927 966 1004 1039 1073 1106 1138 1169 1199 1229 1258 1286 1314 1341 1367 1393 1419 1444 1469
170   782 829 874 916 957 996 1034 1071 1106 1140 1173 1205 1236 1266 1296 1325 1354 1382 1409 1436 1462 1488 1514
180   805 853 900 943 985 1025 1064 1102 1138 1173 1207 1240 1272 1303 1334 1364 1393 1422 1450 1478 1505 1532 1558
190     877 924 969 1013 1053 1093 1132 1169 1205 1240 1274 1307 1339 1370 1401 1431 1461 1490 1518 1546 1573 1600
200     900 948 995 1039 1081 1122 1161 1199 1236 1272 1307 1341 1374 1406 1437 1468 1499 1529 1558 1586 1614 1642
210     928 974 1019 1064 1107 1149 1189 1229 1264 1298 1336 1374 1408 1441 1473 1505 1536 1566 1596 1625 1654 1683
220       1000 1042 1089 1133 1176 1217 1258 1291 1324 1365 1406 1441 1475 1508 1541 1572 1603 1634 1664 1693 1722
230       1019 1067 1114 1159 1203 1245 1286 1323 1359 1398 1437 1473 1508 1542 1575 1607 1639 1663 1701 1724 1761
240         1091 1138 1184 1229 1272 1314 1354 1393 1431 1468 1505 1541 1575 1609 1642 1675 1692 1738 1754 1799
250         1111 1162 1208 1254 1298 1341 1380 1422 1458 1499 1533 1572 1606 1642 1675 1709 1733 1774 1797 1836
260           1184 1232 1278 1323 1367 1406 1450 1484 1529 1560 1603 1636 1675 1708 1743 1774 1809 1840 1872
270           1207 1256 1303 1349 1401 1433 1478 1515 1557 1592 1634 1668 1692 1741 1776 1808 1843 1875 1908
280             1279 1327 1374 1435 1460 1505 1546 1586 1624 1664 1700 1738 1774 1809 1842 1877 1910 1943
290             1302 1351 1400 1452 1486 1532 1573 1614 1653 1693 1729 1754 1804 1841 1873 1910 1939 1977
300               1374 1425 1469 1512 1558 1600 1642 1682 1722 1758 1799 1834 1872 1904 1943 1968 2011
320                 1469 1516 1564 1610 1654 1696 1738 1778 1816 1859 1894 1932 1970 2008 2024 2078
340                   1564 1612 1658 1704 1748 1792 1833 1872 1915 1954 1993 2032 2069 2096 2141
360                     1658 1706 1754 1800 1844 1886 1928 1971 2012 2050 2090 2128 2166 2204
380                       1753 1802 1848 1894 1938 1982 2025 2066 2107 2148 2187 2226 2264
400                       1800 1848 1900 1944 1990 2034 2077 2120 2162 2204 2244 2284 2322
425                           1950 2014 2056 2077 2142 2187 2226 2268 2317 2353 2396
450                           2014 2056 2120 2150 2190 2200 2300 2332 2374 2417 2459
475                               2175 2210 2268 2310 2353 2416 2445 2480 2523
500                                   2332 2370 2412 2459 2523 2565 2608
FORMULA.
N = S
Ldπ or S
Ld3.1416.
Where S = whole surface,
Where L = length,
Where d = diameter, in feet,
Where π = 3.1416,
Where N = the number.
Example.

Diameter two inches, surface 1466, length fourteen feet, we have,

N = 1466
14 × 0.167 × 3.1416 = 200.

375. Table 10. Giving the number and dimensions of tubes to obtain any given amount of surface.

L’gth. Diam. 1½ Diam. 1¾ Diam. 1⅞ Diam. 2 Diam. 2⅛ Diam. 2¼ Diam. 2⅜ Diam. 2½ L’gth.
8 314 336 397 419 445 471 504 523 8
8½ 334 389 422 445 473 500 535 556 8½
9 352 411 447 471 507 530 566 588 9
9½ 372 435 471 497 523 559 597 621 9½
10 392 457 496 524 556 589 628 655 10
10½ 411 480 521 549 584 618 659 687 10½
11 431 503 545 576 612 647 690 720 11
11½ 451 526 570 602 640 677 721 753 11½
12 471 549 595 628 667 705 752 786 12
12½ 490 572 620 654 695 735 783 818 12½
13 510 595 645 681 723 764 814 851 13
13½ 530 617 669 707 750 793 845 884 13½
14 549 640 695 733 778 823 876 916 14
14½ 569 663 719 759 806 852 907 949 14½
15 589 686 744 785 834 882 938 982 15
15½ 608 708 769 811 861 911 969 1015 15½
16 628 731 794 837 889 941 1000 1048 16
16½ 648 754 819 863 917 971 1031 1081 16½
17 668 777 843 889 945 1000 1062 1114 17
FORMULA.
13.5√a – 28,

where a is the percentage of admission.

Example.

What is the mean pressure, with an initial pressure of one hundred pounds, and sixty per cent. admission.

13.5√60 – 28 = (13.5 × 7.7) – 28 = 76
100 of 100, or 76 lbs.

376. Table 11. Showing the mean cylinder steam pressure for any percentage of admission, the initial pressure being from 50 to 150 lbs. per inch.

Initial pressure in pounds. MEAN CYLINDER PRESSURE, ADMISSION BEING IN HUNDREDTHS OF THE STROKE.
10 15 20 25 30 35 40 45 50 55 60 65 70 75
50 7 12 16 20 23 26 28 31 33 36 38 40 42 44
60 9 14 19 24 28 31 34 37 40 43 46 49 51 53
70 10 17 22 28 33 36 40 43 47 50 54 57 59 62
80 12 19 26 32 38 42 41 49 54 58 62 65 68 71
90 13 22 29 36 42 47 51 54 60 65 69 73 76 80
100 15 24 32 40 47 52 57 62 67 72 77 81 85 89
110 16 26 35 44 52 57 63 68 74 79 85 89 93 98
120 18 29 38 48 56 62 68 74 80 86 91 97 102 107
130 19 31 42 52 61 68 74 81 87 94 99 105 110 116
145 21 34 45 56 65 73 80 87 94 101 107 113 119 125
160 22 36 48 60 70 78 85 93 100 108 114 121 127 134