Find the weight in pounds, per yard; two-thirds of which will give the safe load, in tons.
A round iron rod of average quality of iron, one inch in diameter, will be torn asunder by 16 tons; it will be perceptibly damaged by half this strain, or 8 tons; its safe load will be one-third, or 5·33 tons.
TIMBER.
To find the area, or superficial content of a plank.
Multiply the length by the mean breadth.[47]
Example.—Required the content of a board whose length is 11 feet 2 inches, and breadth 1 foot 10 inches
| ft. in. ft. in. | ft. in. | ||
| 11 2 × 1 10 | = | 20 5. | Content required. |
To find the solid content of squared, or four-sided timber.
Multiply the mean breadth by the mean thickness, and the product by the length, for the content, nearly.