Among the more important units of volume are the cubic inch, the cubic foot. the cubic yard. and the cubic mile. The cubic inch is prac tically the smallest unit of volume based directly on linear units. It is very largely used The cubic foot (1,728 cubic inches) is used in engineering to express volumes of gas, water, or other solids. In some States, such as Wash ington and Colorado, the cubic foot is estab lished by statute as the legal unit for measur ing the volume of water. A special system of urns is used in the measurement of wood: 144 cubic inches or one foot square of one inch hoard is expressed as one board foot. A timber foot, however, is 1,728 cubic inches or one cubic foot A cord foot is a pile of wood I by 4 by 4 feet. A cord of wood is 8 cord feet. In the lum ber business boards are usually bought and sold by the 1,000 hoard feet to simplify computa tion, In New Hampshire, a measure for him ber was adopted in 1866 based upon an °imagi nary cubic foot' equal to about 1.4 cubic feet. This unit is also used in parts of Maine and Vermont. Round timber is measured as fol s 'A stick of timber 16 inches in diameter and 12 inches in length shall constitute one cubic foot. and the same ratio shall apply to any other size and quantity. Each cubic foot shall constitute 10 feet of 1,000 board feet.' In the practical use of this rule it is customary to consider 115 cubic feet equivalent to 1 000 board feet. instead of 100 cubic feet, according to the of the statute. In this case the diame ter is taken at the middle of the log inside the bark. If the diameter is measured at the small end of the log, 106 cubic feet are allowed for 1.000 board feet. The New Hampshire rule is called the Blodgett Rule. The Doyle is the standard of log measurement in Arkansas for logs cut and sold or hauled. A large variety of log rules is in use throughout the country. These are locally accepted as standards, but they differ among themselves in so confusing a man ner as to make it impossible to give an ac curate and complete statement concerning them. The cubic yard is used largely in engineering and in computing grading, cuts and fills, a cubic yard being equal to about one load.
The perch, in addition to being a unit of length and a unit of area, is also widely used as a unit of volume of brickwork and masonry. The perch of brickwork, however. is a widely varying unit, ranging from 161; cubic feet to 25 cubic feet In Colorado it is 161/4 cubic feet, in Philadelphia 22 cubic feet, 25 cubic feet in North and South Dakota, 24S: cubic feet in other places. The latter perch is equal to a section of brickwork I by 1 th feet by 161/4 feet or one perch in length.
A cord of masonry is usually reckoned at 100 cubic feet, although in some cases it is 96 cubic feet.
The cubic mile is used in expressing very large volumes, such as the silt carried by rivers.
Liquid The fundamental unit of liquid measures in the United States is the wine gallon of 2.11 cubic inches — a unit abandoned by England in 187.4. but now generally adopted by the various States of the Union. The Brit ish Imperial gallon measures 277274 cubic inches, and is the volume of 10 pounds of water at or F. The liquid measures of the United
States unfortunately bear no relation to those of England. Much confusion is occasioned by the use of the ambiguous term gallon, as there are in the United States the wine gallon (231 cubic inches), the ale, beer or milk gallon (282 cubic inches). and the dry gallon, besides the 'ool gallon.' the unit for internal revenue taxation The 'proof gallon' is a wine gal lon of spirits containing one-half its volume of nearly pure alcohol at 60' F. and is the basis for computing the United States internal revenue tax. For example, a gallon of spirits containing 40 per cent alcohol would be 80 per cent proof and the number of proof gal lons is computed by multiplying the per cent of proof by the number of wine gallons. Wiscon sin and Connecticut still retain the dry gallon of 282 cubic inches as a legal standarcl. New Hampshire and Minnesota definitely retain the ale, beer or milk gallon of 282 cubic inches. and Maine definitely mentions the same unit among its list of State standards. A Minnesota statute provides that the 'Beer arid milk mea sures shall contain the following capacities: The gallon shall contain 282 cubic inches. The half gallon shall contain 141 cubic inches, and the quart one-half as much, and the Dim onc half as much as the quart. The milk gallon thus established is 51 cubic inches larger than the standard gallon used more generally throughout the country. There are thus three different quarts, the dry quart derived from the NVinchester bushel, the liquid quart derived from the wine gallon, and the liquid quart de rived from the beer or milk gallon. The differ ences, of course, extend proportionately to all the multiples and subdivision.: of these units. The ordinary liquid measures are usually 1 gallon = 4 quarts= 8 pints = 32 gills. In ad dition to the capacity measurement by volume, the legal weight of a gallon of certain commodi ties have been fixed by statute in some States, and in several cases by Congress for certain pur poses. Thus 12 pounds of strained honey is a legal gallon in Nebraska, 61/4 pounds of kero sene (Kansas), and 71, pounds of kerosene in Ohio, 11 pounds of sorghum molasses (In diana). 11 pounds of maple syrup (New York), 8 pounds of castor oil (Kansas) are all legal gallons of the products named. These legal weights differ among themselves, and do not accord with the true volume of one gallon of 2.31 cubic inches.
The subdivisions of the gallon, the quart, pint and gill arc largely used in trade. In ad dition to the general liquid measures enumerated above. apothecaries base a special system of capacity measures based on the volume of the United States liquid pint of 28.875 cubic inches. One pint = 16 United States fluid ounces = 128 United States fluid drams = 7,680 United States The minim is the smallest of the United States units of volume and is about 0.00376 cubic inches. A minim of pure water weighs about 0.95 grains and corresponds to the 'drop.' which it approximates in size. The United States minim is about 4 per cent larger than the British Imperial minim. It is denoted by the symbol R.