Avoirdupois weight is used for weighing all ordinary articles, such as live stock, grain, hay, vegetables, etc. The standard avoirdupois pound of the United States is determined from the Troy pound, and contains 7,000 grains Troy. In some states 2,240 pounds are considered one ton. Troy Weight

Troy weight is used in weighing gold, silver and jewels. Pearls and diamonds are weighed by the karat of 4 grains, 5 diamond grains being equal to 4 grains Troy. The Troy pound, containing 5,760 grains, is the standard unit of all weights in the United States.

Apothecaries' weight is used only in weighing of medicines.

Linear measure is used only in measuring distances or length in any direction. The yard is the standard unit of length.

Square measure is used in measuring anything which has both length and breadth; that is, surface measure of two dimensions only.

Note.-311⁄2 gallons, in some instances, are considered a barrel.

In figuring board measure, all boards are assumed to be 1 inch thick. To find the contents of lumber, multiply the length in feet by the width and thickness in inches and divide by 12.

First: 1 in. x 12 in. x 8 ft.: 1×12×8÷12=8 sq. ft.

Second: 1⁄2 in x 12 in. x 8 ft.: 2X12X8÷12=4 sq. ft.
Third: 6 in. x 8 in. x 16 ft.: 6X8X16÷12=64 sq. ft.

To convert English money into American money: Reduce the English money to pence. Divide the rate of exchange (normal 4.8665) by 240, the number of pence in one pound, the result will be the value of one penny in American exchange. Multiply the total number of pence to be converted by the value of one penny, the result will be the equivalent in dollars and cents.

Rate of exchange is $4.80. £6 18s 9d = 1,665d. $4.80÷240= .02, value of one penny. 1,665dX.02= $33.30.