152
IRON.
boiler. The burnt air goes off through pp into a small chimney, through the openingb b, which is regulated by a valve.
In the following Table, each bar is reduced to exactly one inch square; and 0\ etransverse strength, which may be taken as a criterion of the value of each iron, i 3obtained from a mean between the experiments upon it, given in the Memoirs;— fl'Ston bars 4 ft. bin. between the supports, and next on those of half the length,‘* r2 ft. 3 in. between the supports. All the other results are deduced from the 4 ft. 6 i*-bars. In all cases the weights were laid on the middle of the bar.
Table of Results obtained from Experiments on the Strength and other Properties olCast Iron, from the principal Iron Works in the United Kingdom . ByMr. Ww>Eairbairn.
scale of strength.
Names of Irons.
Number of Experiments on each.
1
Specific gravity.
Modulus of elasticityin lbs. per squareinch, or stifl’ness.f
^3 SO i
!
Ill
!?!
Breaking weight in lbs.
of bars 2 ft. 3 in. re-
| duced to 4 ft. 6 in. be-
1 tween supports.
Mean breaking weight
in lbs. (S.l
Ultimate deflection of
4 ft. 6 in. bars, in
parts of an inch.
Power of the 4 ft/G in.
bar3 to resist imnact.
Color.
Quality-
; 1
Ponkey, No. 3. Cold Blast - • •
4
7-122
17211000
667
595
581
1-747
992 Whitish gray
Hard.
Devon, No. 3. Hot Blast* - -
2
7-251
22473651
537
—
537
1-0-.)
589 White - -
Oldberry, No. 3. Hot Blast
6
7-300
•22733401
543
517
53C
L-005
549 White • •
Hard.
Carrou, No. 3. Hot Blast* • - -
2
7-056
17873101
520
534
527
1-365
Hard.
Beaufort, No. 3. Hot Blast - - -
6
7-069
1080200C
505
529
517
1-599
807 Dullish gray
Butterley.
4
7-038
1537951X
489
515
502
1-815
Soft.
Bute, No. 1. Cold Blast - - -
4
7-066
15163001
495
487
491
\l-764
872 Bluish gray
Wind Mill End, No. 2. Cold Blast
4
7-071
16490001
48!}
495
489
1-581
Old Park, No. 2. Cold Blast • •
5
7-049
14607001
441
529
48f
1-621
718 Grny - - -
Soft.
Beaufort, No. 2. Hot Blast - •
4
7-108
1630101K
478
470
47-;
1-512
Hard.
Low Moor, No. 2. Cold Blast • -
4
7-055
14509501
483
472
1-852
Soft. ,
ButFery,No. 1. Cold lilast* • -
5
7-079
15381201
463
_
1-55
Rather bard-
Brimbo, No. 2. Cold Blast - - .
5
7-017
14911666
466
453
45?
1-743
815.Light gray -
Rather hard.
‘r 14
Apedale, No. 2. Hot Blast - -
3
7-017
14852001
457
455
456
1*730
Stiff.
1 15
Oldberry, No. 2. Cold Blast - -
4
7-059
1430750C
453
457
45f
1-811
822 Dark gray -
Rather soft-
Pentwyn, No. 2..
4
7-038
15J930OC
438
173
1-484
Maesteg, No. 2. ..
5
7-038
13959500
455
Rather sott.
Muirkirk, No. 1. Cold Blast* - -
4
7-113
IRKKlofin
464
Fluid.
19
Adelphi, No. 2. Cold Blast - -
5
7-080
13815500
441
457
449
1-759
7771 Light gray -
Soft.
Blama, No. 3. Cold Blast -
6
7-159
14281466
433
464
448
1-7-26
Hard.
Devon, No. 3. Cold Blast* - • -
4
7-285
0-2907700
448
_
448
•790
Hard.
Gartsherrie, No. 3. Hot Blast - -
6
7-017
13894000
427
467
447
998'Light gray -
Soft.
Frood, No. 2. Cold Blast • - .
5
7-031
13112666
460
434
447
1-825
841
Open.
Lane End, No. 2..
3
7-0-28
15787666
444
_
Soft.
Carron, No. 3. Cold Blast* - - -
5
7-094
16-246966
444
443
443
Soft. .
26
Dundivati, No. 3. Cold Blast - -
4
7-087
16534000
466
430
4-13
1-469
674
Rather bOU-
Maesteg (Marked Red) - - - -
5
7-038
13971500
440
444
442
Corbyns Hall, No. 2. ....
6
7-007
L3S45866
430
464
442
Soft.
29
Pontypool, No. 2..
5
7-080
13136500
439
441
440
Rather soft-
Wallbrook, No. 3. .
5
6-979
15394766
432
449
440
625
llatlier hard-
31
Milton, No. 3. Hot Blast - - .
4
7-051
.5852500
427
449
438
585
Rather hard-
Bufiery, No. 1. Hot Blast* - -
3
6-998
13730500
436
_
4-36
Soft.
33
Level, No. 1. Hot Blast ....
5'
7-080
15452500
461
403
432
1-516
699
Soft. .
5
6-975
.5280900
408
466
431
1-251
511
Rather ba* 5 '
35
Level, No. 2. Hot Blast ....
6
7*031
.5241000
419
439
429
570
Soft.
36
5
7-041
4953333
413
416
429
1-339
551
Soft.
Eagle Foundry, No. 2. Hot Blast
4
7-038
4211000
408
446
427
1-512
618
Soft.
Elsicar, No. 2. Cold Blast - • -
4
6-928
.2586500
446
408
427
Soft.
39
Varteg, No. 2. Hot Blast - • •
4
7-007
5012000
422
430
426
1-450
6-21
Hard. A
40
Coltham, No. 1. Hot Blast • -
5
7-128
5510066
464
385
424
1-532
716
Rather soft-
41
Carroll, No. 2 Cold Blast - - -
4
7-069
7036000
430
408
419
1-211
530
Hard.
42
Muirkirk, No. 1. Hot Blast* - -
4
6-953
3294400
417
419
418
1-570
656
Soft.
Bierley, No. 2..
5
7-185
6156133
404
432
418
1-222
494
Soft.
Coed-Talon, No. 2. Hot Bla3t* -
4
6-969
4322500
409
424
416
1-882
771
45
Coed-Talon, No. 2. Cold Blast*
6
6-955
4304000
408
418
413
1-470
600
[lather s°> 1 -
46
Monkland, No. 2. Hot Blast - -
3
6-916
2259500
402
404
403
1-762
709
Soft.
47
Ley’s Works, No. 1. Hot Blast - 1
3
3-957
1539333
392
_
392
1-890
742
Milton, No. 1. Hot Blast - - - |
4
3-976 11974500
353
385
369
1*525
638
Gray ...
Softj
49 1
Plaflkynostou, No. 2. Hot Blast - I
5
6-916 U3341633
378
337
357
1-366
517
Light gray 1
Rule .—To find from the above table the breaking weight in rectangular bars, *> e f^ erally, calling b and d the breadth and depth in inches, and l the distance between
supports in feet, and putting 4-5 for 4 ft. 6 in., we have- ** _ p r eaki n ?
weight in lbs., the value of S being taken from the table above.
J\Io° r
for example :—What weight would be necessary to break a bar of Rowiron, 2 inches broad, 3 inches deep, and 6 feet between the supports ? Accordingthe rule given above, we have 6=2 inches, d— 3 inches, 1=6 feet, 5=472 fro 111
table. Then = 4r5XgX 3g)<472 = 6372 lbs., the breaking weight.
^6 " pjr
* The irons with asterisks aro taken from the experiments on hot and cold blast iron, ma< H5 e nthHodgkinson and myself for the British Association for the Advancement of Science.—SeeReport, vol. vi. ' ft gin
t The modulus of elasticity was usually taken from the deflection caused by 112 lbs. on the 41 •oars.