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Gartsherrie 3 H
Frood

2 C
Carron

30
Lane End 2
Dundyvan

3C 4
Maesteg
Corbyn's Hall 2
Blaenavon

2
Pontypool

2
Wallbrook

3
Milton

3 H 4
Buffery 1H 3
Level

1H 5
Pant

2
Level

2 H
Eagle Foundry 2 H 4
Elsicar

2 C 4
Varteg

2 H 4
Coltham 1H 5
Carroll

20 4
Muirkirk 1H 4
Bierley

2
Coed-Talon 2 H
Coed-Talon 2 C 5
Monkland 2 H 3
Bowling 2 3
Ley's Works.. IH 3
Milton

1H

4
Plaskynaston 2 H

Sum = 221

7.017 13,894,000
7.031 14,112,666
7.094 | 16,246,966
7.028 15,787,666
7.087 | 16,531,000
7.038 13,971,500
7.007 13,845,866
6.920 13,790,000
7.080 13,136,500
6:979 | 15,394,766
7.051 15,852,500
6.998 13,730,500
7.080 | 15,452,500
6.979 15,280,900
7.031 15,241,000
7.038 14,211,000
6.928 | 12,586,500
7.007 | 15,012,000
7.128 15,510,066
7.069 17,036,000
6.953 13,294,400
7.185 | 16,156,133
6.969 14,322,500
6.955 | 14,304,000
6.916 | 12,259,500
7.014 | 14,130,000
6.957 11,539,333*
6.976 | 11,974,500
6.916* 13,341,633

·000031092043 07811 79.83 681 02117 7.210
00003061 2043 09133 91.21 681 .02037 6.936
00002659 2038 06701 68.28 679 .018056.130
00002737 2029.07091 | 71.97 676 01850 6.254
00002613 2025 07357 74.53 675 01764 5.952
•00003092 2020 .09440 95.34 673 .02082 7.002
•00003120 2020 :08154 85.38 673 02100 7.066
· 00003133 2012 0892889.82 671 .02102 6.813
·00003288 2011 09300 93.56 670 .02203 7.381
00002806 2011 :07236 72.80 670.01880 6.299
· 00002725 2002 .06862

68.69 667 .01818 6.062
·00003147 1933 .08223 81.94 664 02089 6.936
00002795 1975 07596 75:01 658 .01810 6.052
.00002827 1971 .06289 61.98 657 .01857 6.102
.00002834 1962 .06818 66.89 654 .01854 6.061
·00003040 1953 -07587 74.09 651 .01979 6.442
• 00003432 1953 -11087* 108.20 651 .02231 7.272
.00002878 1948 :07274 70.85 619 .01868 6.061
· 00002785 1939:07676 74.42 646 .01800 5.812
· 00002536 1917 1.06179 59.91 639 .01620 5.177
·00003250 1917 .07881 76.41 639 .02076 6.634
·00002674 1912.06141 58.71 637 . 01703 5.425
.00003016 1903 .09412 89.55 634 :01912 6.062
·00003020 1890 07378 69:72 630 .01903 5.993
•00003524 1890 .08840 83.54 630 .02220 6.993
·00003059 1850 :07768 71.85 617 .01886 5.820
•00003744* 1795 •07561

67.86 598 02239 6.694
· 00003608 1692 1.07673 64.91 561 .02035 5.738
.00003238 1638 06873 56.29 | 546 .01768 4.827

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Mean

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In which D, = the external, and do = the internal diameter,

in inches. = the external, and do = the internal depth or

vertical diameter in Elliptical sections. DB = the external, and db = the internal breadth or

horizontal diameter in Elliptical sections. L = the length of the beam in feet. W = the load in lbs., tons, &c., dependent on the

terms of Mr. Mr = Multiplier which varies with the Material, mode

of fixing, loading, &c.: the value for rectangular and cylindrical beams is given by

Tables 64, 65, 66, and the Ratios in (359),(362). (335.) The value of My may be found from direct experiment by rule (327). Its most useful value is when W = the ultimate or breaking weight in the centre of a rectangular beam supported at both ends :-in that case it is simply the breaking load of a beam 1 inch square and 1 foot long.

Table 64 gives in col. 7 the mean value of M, for the breaking weight of 54 kinds of British cast iron at 2063 lbs., or 18.4 cwts., or .92 ton, and of course W will come out in lbs., cwt., or tons according to the Multiplier used col. 10 gives M, for the safe dead load, which is taken at 3rd of the breaking weight. This Table is based on Fairbairn and Hodgkinson's experiments.

Table 65 gives the value of M, for Timber, and Table 66 a reduced and condensed general summary. Table 67 gives the Transverse strength in connection with the Stiffness for the Safe working load as well as for the breaking weight: the ratio which these should bear to one another, or the “Factor of Safety,” varies with the nature of the material and the character of the Strain, &c. See (880), &c.

(336.) The application of the rules and Tables may be illustrated by examples. Thus to find the breaking weight for a beam of English Oak, 12 inches deep, 6 inches wide, and 15 feet long ;-we may take M, from col. 6 of Table 66 at .2272 ton; then the rule (324) becomes 122 x 6 x 2272 = 15 tons breaking weight in the centre. Again: to find the depth of a beam of Riga Fir 10 feet long, 3 inches wide, to carry the

= 13:1

TABLE 65.-Of the TRANSVERSE STRENGTH of TIMBER, or the Value

of MT, being the central Breaking Weight of a Beam 1 inch square, 1 foot long between end bearings.

Kind of Wood.

Max.

Min.

Mean.

Authority and Number of

Experiments.

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Alder ..

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99

lbs. lbs. lbs. tons. Acacia

747 •3334 P. W. Barlow. green

622 2776 1 Ebbels.

530 •2366 1 Ash, common

682 665 675 •3014 6 Barlow.
597 490 542 • 2420 3 Peake and Barrallier.

815 3638 2 P. W. Barlow.
635 2830 1 Ebbels.

785 •3504 1 Tredgold. » young

810 •3616 1 American

517 2308 Nelson,

680 .3054 Depison. Swamp

388 • 1732 Black

287 •1281 Beech, common

538 494 519 2317 3 Barlow.

677 .3022 1 Ebbels. American, White

460 • 2054 Denison. Red

573 - 2560 Nelson.

586 *2610 Denison. Birch, common

815 727 771 • 3442 2 P. W. Barlow.

518 2312 1 Ebbels.
American,Black 896 572 727 • 3250 4 P. W. Barlow.

616 • 2750 Nelson,
603 - 2700 Barlow.

842 •3760 Denison.
Yellow

445 • 2000 Cedar, Lebanon

498 .2223

412 1840 1 Tredgold. Bermuda

465 • 2760 Nelson. Guadaloupe

681 • 3040 · American, White

•1140 Denison. Chestnut, green

450 • 2009 1 Ebbels. Spanish,dry 592 382 487 • 2176 2 Tredgold. Deal, Christiania 657 587 622 •2780 2 P. W. Barlow.

686 • 3060 1 Tredgold.

521 .2326 Barlow. Memel

692 • 3090 P. W. Barlow.

545 • 2433 1 Tredgold. Eỉm, English

348 334 338 1500 3 Barlow,
481 412 417 • 2000 2 P. W. Barlow.

540 • 2410 1 Ebbels.

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TABLE 65.—TRANSVERSE STRENGTH of TIMBEE, &c.—continued.

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lbs. lbs.

Ihs. tons.

480 2140 1 Ebbels. 518 308 404 -1803 25 Beaufoy. 425 275 359 . 1602 6 Barlow. 550 280 382 1705 27 Peake and Barrallier.

437 1951 37
480 350 390

17414
525 327 407 • 1817 9 Barlow.

392 .1750 1 Ebbels.
465

• 20761
414 225 330

• 1473 13 Barlow.
425 332 375 1674 4 Peake and Barrallier.
632 322 504 .2250 3 Tredgold.

671 .3000 Nelson.
425 .1897

1 Tredgold.
637 - 2844 1
584 • 2607 Nelson.
501

.2237 Moore.
635 - 2840 Young.
565

- 2522 Denison.
568 368 475 - 2120 6 Barlow.
568

364 418 1866 19 Beaufoy.
904 423 663 • 2959 6 P. W. Barlow.

639 .2852 Moore.
543 .2424 Nelson.
519

-2317 Denison.
710

-3170 1 Ebbels. 964 • 4303 1 Tredguld. 660

• 29461

547 .2442 1 Ebbels. 570 434 496 .2214 8 Buffon. 507 455 490 .2187 3 Barlow. 428 224 334 · 1491 25 Beaufoy.

526 2322 Moore.
620 570 589 •2629 3 Barlow.

566 2530 Nelson,
566 2530 Moore.

603 -2700 Denison.
490 437 461

• 2058 3 Barlow.
519 .2317 Moore.
569 - 2540 Nelson.
555
.2480

Denison.
621 .2770 Nelson,

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TABLE 65.-TRANSVERSE STRENGTH of TIMBER, &c.—continued.

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