XXXIX.]
CARBONISING.
323
I examined these specimens in 1863 and 1864, and they all appeared to be as strong and sound as when first prepared; they were therefore returned to their places. I again examined them in 1867, and then tested them for transverse strength. The results are given in the following tables :—
Number of the specimen. |
Deflections. | Total weight required to break each piece. |
Specific gravity. |
Weight required to break 1 square inch. | |||
With the apparatus weighing 390 lbs. |
At the crisis of breaking. | ||||||
Inches. | Inches. | lbs. | lbs. | Kept dry in the store-room. | |||
03 | 2.45 | 4.45 | 660 | 626 | 165.00 | ||
10 | 2.55 | 4.55 | 690 | 622 | 172.50 | ||
Total | 5.00 | 9.00 | 1350 | 1248 | 337.50 | ||
Average | 2.50 | 4.50 | 675 | 624 | 168.75 | ||
7 | 3.00 | 4.25 | 345 | 1036 | 86.25 | Kept in a box of manure. | |
8 | 3.50 | 5.00 | 490 | 1095 | 122.56 | ||
9 | 3.25 | 575 | 530 | 1080 | 132.50 | ||
Total | 9.75 | 15.000 | 1.365 | 3211 | 341.25 | ||
Average | 3.25 | 5.00 | 455 | 1070 | 113.75 | ||
11 | — | — | — | — | — | ||
12 | 2.75 | 4.50 | 480 | 946 | 120.00 |
Remarks.—No. 3 broke with scarph-like fracture, 5 inches in length; 10 broke in three pieces, each with scarph of 6 inches ; 7 broke with long splintery fracture ; 8 broke with splinters, 12 inches in length; 9 broke with splinters, 9 inches in length; 11, lost; 12 broke off short in three pieces.