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TABLE 1.-Of the TENSILE STRENGTH OF MATERIALS--continued.

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Bismuth
Brass, yellow, cast

copper 2, zinc 1
Gun-metal, copper 9, tin 1
Muntz-metal, copper 6, zinc 4
Copper, cast, pure
Copper bolts, 23, 2, 1, and inch diameter

cast
hammered

wire
Copper 12, tin 1, cast

1,

wire
milled sheet

drawn pipe
Silver, cast

11, 1, 10,

9, 1,
Lead, cast

wire
Platinum, wire
Tin, cast

wire
Zinc, cast

sheet
wire

lbs.

tons
3,692 1.65 Muschenbroek.
17,968 8:01 Rennie.
28,940 12.9

Anderson,
31,280 14.0
49,280 22:0
31,830 14.2
35,930 16:0
20,638 9.21 Rennie.
33,792 15:1
63,230 28.2
29,000 12.95 Anderson.
30,700 13.70
33,000 14.73
38,000 17.00

1,814 0.81 Rennie.
2,757 1.23 Morveau, &c.
3,328 1:48 Tredgold,
2,510 | 1:10 Jardine.
40,902 18.26 Muschenbroek.
38,256 17.08 Sickingen.
54,730 24:43 Morveau, &c.
5,566 2.48 Rennie, &c.
6,765 | 3:02 Morveau, &c.
2,689 1.2 Muschenbroek.
16,600 | 7:41 Tredgold.
22,550 10.07 Morveau.

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6,650
7,129

52,987
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6,400

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TABLE 1-continued.TENSILE STRENGTH OF TIMBER.
Max.
Mean. Authority.
Kind of Wood. Max.

Authority.
Ibs.
Ibs.

Ibs.

lbs.
14,186 6:3 Muschenbroek. Holly

16,000 7.1 Bevan.
19,500 8.7 Bevan.

Lance-wood 24,696 23,400 24,048 10.7
17,850 15,784 17,077 7.6 6. Barlow. Larch

8,900 4.0
19,600 16,700 18,150 8:1 2. Bevan.

10,220 4.6 Rondelet.
12,000 5.4 Muschenbroek. Lignum-vita

11,800 5.3 Bevan. 11,62611,388 11,467 5.1 3. Barlow. Mahogany

8,224 7,950 8,041 36 3. Barlow. 17,709 7.9 Muschenbroek.

21,800 16,500 19,150 8.5 Bevan. 22,200 9.8 Bevan. Maple

17,400 7.8 15,000 6.7

Oak, English 12,008 8,889 10,389 4.6 6. "Barlow. 20,348 19,595 19,890 8.9 3. "Barlow.

19,800 15,000 17,400 7.8 2. Bevan. 15,500 6.9 Bevan.

17,300 7:7 Muschenbroek, 20,000 90 Muschenbroek.

13,950 6:2 Rondolet. 11,400 5:1 Bevan.

Pear-tree

11,537 8,834 9,822 4.4 3. Barlow. 4,973 2.2 Muschenbroek. Pine, St. Petersburg

13,300 5.9 Bevan. 12,100 5:4 Bevan.

7,818 3.5

Muschenbroek. 10,500 4.7

Norway

14,300 12,400 13,350 6.0 Bevan, 13,300 6:0 Muschenbroek. Plane-tree

11,700 5.2 14,000 6.3 Bevan. Plum-tree

11,800 5.3

Muschenbroek. 18,100 17,600 17,850 8.0

Poplar

6,641 4,596 5,618 2.5 14,000 12,300 12,900 5.8

7,200 3.2

Bevan.
7,000 3:1
Sycamore

13,000 5.8
15,000 6.7

Teak

15,405 14,662 15,090 6:7 3. Barlow. 10,000 4.5 Muschenbroek. old

8,200 3.7 Bevan. 13,490 6.0 Walnut..

7,800 3.5 14,400 6.4 Bevan.

8,130 3.7 Muschenbroek. 13,448 11,000 12,203 5.5 12. Barlow. Willow

12,500 5:6 10,700 9,200 9,950 4.4 Bevan.

14,000 6.3 Bevan. 18,000 8.0 Yew, Spanish

8,000 3.6 20,700 9.2 Hatfield.

STRAIN PERPENDICULAR TO THE GRAIN. 1,700 970 1,335 596 Tredgold.

Memel

8401 540 690 .310 Bevan. 2,3161.031 Fir, Scotch

562 250 1,782 796

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Larch
Oak, English
Poplar

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101,710
119,360
138,440
158,920
180,820

45.40 53.28 61.80 70.94 80.72

83,520 98,020 113,680 130,500 148,480

32.93 38.64 44.82

73,760 86,560 100,390 115,240 131, 120

43.76

11 11 2

50.75 58.26 66.28

51.54

58.53

91.12

25 21 23 21 29

204, 120
228,840
254,980
282,530
311,480

102:1
113.8

167,620
187,920
209,380
232,000
255,780

74.83 83.89 93.47 103.5 114.2

148,030 165,950 184,900 204,880 225,880

66.08 74.08 82.54 91.46 100.8

126:1

139.0

110.7

23 24 3

341,850
373, 630
406,830

152.6
166.8

280,720
306,820
334,080

125.3
136.9

247,900
270,950
295,040

120.9
131.7

181.6

149.6

(1)

(2)

(3)

(4)

(5)

(6)

NOTE.—The diameters of the screwed bars

of Round Bars of IRON, STEEL, and COPPER.

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0.78
1.76

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3:14

4.91
7.06

64,380 28-74 27,530 12:28 9,616 4:30 21,550 9.62

84,090 37:54 35,950 16:05 12,560 5.61 28,100 12.55 1 106,440 47:51 45,500 20:31 15,900 7.11 35,630 15.91 17 131,380 58.65 56,200 25.08 19,620 8.77 44,000 19.64 11 158,970 70.97 68,000 30.35 23,750 10.6253,220 23.76 13 189, 190 81:46 80,900 36.10 28,260 12.64 63,230 28-23 1} 222,050 99.13 94,970 42.39 33,180 14.81 74,350 33.19 19 257,600 115.0 110,100 49.12 38,460 17.24 86,180 38.47 13 295,680 132.0 126,450 56:55 44,170 19.72 98,980 44.19 13 336,450 150 2 143,810 64.20 50,240 22:46 112,380 50.17 2 379,680 169.5 163,000 72.76 56,740 25.33 127,090 56.74 21 425,600 190-0 182,010 81.24 63,580 28:43 142,520 63.63 27 474,430 211.8 202,770 90·52 70,880 31.64 158,820

70.90 23 525,500 234.6 224,780 100 3 78,540 35.10 176,000 78.57 21 579,490 258.7 247,730 110.6 86,590 38.66 193,970 86.60 25 635,940 283.9 272,010 121.4 94,980 42:47 212,880 95.04 29 695,070 310 3 297,200 132.6 103,870 46.33 232,160 103.6 2} 757,120 338.0 323,580 144:4 113,010 50-54 252,920 112:9 3 (7)

(10) (11) (12) (13) (14)

(8)

(9)

are measured at the top of the thread.

gradually rose to a maximum with the 12th, beyond which to the 18th they were progressively reduced. The crushing strain was reduced to its first minimum with the 4th melting, and attained its maximum with the 14th. Taking the iron of the 1st melting as a standard, the maximum increase in strength due to re-melting was 32 per cent. with the tensile ; 41 per cent. with the transverse, and 135 per cent. with the crushing strain. It should be observed that Mr. Fairbairn's experiments did not include the tensile strain : col. 4 in Table 3 has been calculated (499) from the transverse and crushing strains in cols. 2 and 3 ; the results in col. 4 are very regular among themselves, despite the irregularities in col. 3.

TABLE 3.-Of the EFFECT of RE-MELTING on the STRENGTH of

Cast Iron.

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(7.) It would appear from all this, that the method of obtaining increased strength by re-melting cast iron is very

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