Width in ¼ ins. X Thickness in 1/8 ins., or vice versa, ÷ 10 X Length, ft. = Weight, lbs. cast iron.

For instance; to find the weight of a casting 3¼ ins. X 1 1/8 ins X 2 ft. 6 ins. long.

13X9 ÷ 10 = 11.7 X 2.5 = 29.25 lbs.

This rule is very useful, and can easily be remembered in the following form.

Width in ¼ ins. X Thickness in 1/8 ins. or vice versa, cut off l figure for decimal, the result is lbs. per foot of length.

For wrought iron add l-20th to the result; for lead add 1-2; lor brass add l-7th; for copper add l-5th.

To find the Weight from the Areas.

Area, sq. ins. X Length, ft. X 3 1-7 = Weight, lbs. cast iron.

Multiplier for Cast iron 3.156 or 3 1-7.

" Wrought iron 3.312 or 3 1-3.

" Lead 4.854

" Brass 3 644

" Copper 3.87

Or, Area, sq. ins. X 10 = lbs. per yard for wrought iron.

To find the Weight in cwts. Area, sq. ins. X Length, ft. ÷ 31.9 = Weight, cwts. cast iron. For wrought iron, divide by 33.6.