2. Divide this by 144, and multiply the quotient by the length of the boiler in feet.
To find the volume of the waterspace in cubic feet.
1. Find the area of the boiler head in square inches.
2. Multiply the square of the outside diameter of one tube by .7854, and multiply this by the number of tubes, and add to the product, the area of the segment above the waterline.
3. Subtract 2 from 1, and divide the remainder by 144.
4. Multiply the quotient by the length of the boiler in feet.
To find the number of braces, necessary for the flat surface above the tubes.
1. Find the area of the segment of the boiler head, which is to be braced, in square inches.
2. Multiply the area, thus found, by the steam pressure in pounds per square inch.
3. Multiply the cross sectional area of one brace by the number of pounds, which it is allowed to carry, per square inch of section.