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Gartsherrie 3 II
Frood

2 C
Carron
Lane End
Dundyvan 30
Maesteg.
Corbyn's Hall 2
Blaenavon

2
Pontypool 2
Wallbrook 3
Milton

3 H
Buffery

1H
Level

1H
Pant

2
Level .. 2 Η
Eagle Foundry 2 H
Elsicar

2 C
Varteg

2 H
Coltham

1H
Carroll

2 C
Muirkirk 1 H
Bierley

2
Coed-Talon 2 H
Coed-Talon 2 C
Monkland 2 H
Bowling .. 2
Ley's Works.. 1 H
Milton

1H
Plaskynaston 2 H

4
3
5
5
6

7.017 13,894,000
7031 14,112,666
7.091 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

00003109 2043 107811 79.83 681 02117 7.210
00003061 2013 09133 91.21 081 .02037 6.936
00002659 2038:06701 68.28 679 01805 6:130
00002737 2029 .07091

71.97 676 1.01850 6.251
·00002613 2025 07357 74.53 675 01764 5.952
.00003092 2020 . 09110

95.34 | 673 .02082 7.002
.00003120 2020 .08151

85.38 673 02100 7.066
• 00003133 2012 08928

89.82 671 .02102 6.813
.00003288 2011 :09300 93.56 670 - 02203 7.381
00002806 2011 1:07236 72.80 670 .01880 6.299
.00002725 2002 .06862 68.69 667 .01818 6.062
.00003117 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
00002831 1962 .06818 66.89 654 01854 6.061
·00003010 1953 1.07587 74:09 651 .01979 6.442
•00003132 1953 11087* 108.20 651 .02231 7.272
.00002878 1918 :07274 | 70.85 619 .01868 6.061

00002785 1939 .07676 74.42 6-16 .01800 5.812
.00002536 1917 1:06179 59.91 639 .01620 5.177
.00003250 1917 .07881 76.41 639 .02076 6.634
.00002071 1912.06141 58.71 637 .01703 5.425
.00003016 1903 :09412 89.55 631 .01912 6.062
·00003020 1890 07378 69:72 630 -01903 5.993
.00003524 1890 1.08810 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 • 07673 61.91 561 02035 5.738
·00003238 1638 06873 56:29 516 .01768 4.827

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15, 242,320

(5)

.00002886

(6)

2063 07850 (7)

(2 )

80.63 688 01971

(9) (10) (11)

6.774 (12)

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(1)

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99

9

T

=

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

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

vertical diameter in Elliptical sections. DB = the external, and d3 = 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 Mt. M = 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 My 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 Mfor the safe dead load, which is taken at žrd of the breaking weight. This Table is based on Fairbairn and Hodgkinson's experiments.

Table 65 gives the value of Mr 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 My from col. 6 of Table 66 at .2272 ton; then the rule (324) becomes 122 x 6 x .2272 15 13:1 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

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.

lbs.

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lbs.

tons. Acacia

747 .3334 P. W. Barlow. green

622 .2776 1 Ebbels. Alder ...

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 Denison, 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

255 •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. Elm, English

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

510 • 2410 1 Ebbels.

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Table 65.—TRANSVERSE STRENGTH of TIMBER, &c.continued.

Kind of Wood.

Max.

Min.

Mean.

Authority and Number of

Experiments.

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99

12

dry

Wet
Dantzic
Mar Forest
Scotch

Spruce
Larch..

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lbs. lbs.

lls. tons.

480 .2110 1 Ebbels.
518 308 404 1803 25 Beaufoy.
4:25 275 359 • 1602 6 Barlow.
550
280

382 · 1705 27 Peake and Barrallier.
437

1951 37 480

350 390 • 1741 4
525 327

407 • 1817 9 Barlow.
392 • 1750 1 Ebbels.

465 • 2076 1
414 225 330

• 1473 13 Barlow.
425 332 375 •1671 4 Peake and Barrallier.
632 322

50+ • 2250 3 Tredgold.
671 •3000 Nelson.
425 1897 1 Tredgold.
637 •2814

1
58+ • 2607 Nelson.
501
.2237

Moore.
635 .2810 Young.

565 .2.22 Devison. 568 368 475 • 2120 Barlow. 568 364 418 • 1866 19 Beaufoy. 904 423

663

•2959 6 P. W. Barlow.
639
• 2852

Moore.
543 • 2124 Nelson.
519 •2317 Deuison.
710 .3170 1 Ebbels.
964 .4303 1 Tredgold.
660 • 2916

1 517 .2412

1 Ebbels. 570 434

496 .2214 8 Buttou. 507 155 490 .2187 3 Barlow. 428 224 334 •1491 25 Beaufoy.

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

506 • 2530 Nelson,
566 - 2530

Moore.
603 • 2700 Denison.
490437 461

2058 3 Barlow. 519 -2317 Moore. 569 .2510 Nelson. 555 • 2480 Denison. 621 .2770

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99

Nelson,

live

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

kind of Wood.

Max.

Min.

Mean.

Authority and Number of

Experiments.

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tons, • 4455 4 P. W. Barlow.

3715 Barlow. .3696 Nelson. •3755 Moore. .3861 Denison. • 2480 Moore. • 2513 • 2000 3 Barlow. • 2900 Nelson. - 2680 Young. . 1920 Moore. . 1875 Denison. .2428 3 Barlow. • 2428 24 Beaufoy. •313+ 7 Peake and Barrallier. • 2710 Denison. .2108 6 Peake and Barrallier. . 1770 Moore. . 1640

Barlow. • 1900 Denison. · 1213

7 Peake and Barrallier. .2165 Nelson. • 1600

Young. •1728 Denison. • 2120 Moore. • 2004 • 2509 . 1603 Barlow. - 2040 Moore. • 2710 1 Ebbels, • 1467 1 .2510 1 • 2000 Moore.

1540 Denison. •2388 1 Ebbels. .3660 3 Barlow. • 2947 2 Peake and Barrallier. .2826 Nelson. *2924 Denison. . 1629 Tredgold. • 2174 Ebbels.

272 485 358 387 475

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99

449 562 359 457

Memel
Riga..

Archangel Plane-tree .. Poplar, Lombardy

Abele Spruce

American Sycamore Teak

607 328 570 419

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99

315 535 821 660

99

892
677

717
612

Willow
Waluut (green)

633 655 365 487

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