STANDARDS OF WEIGHT.

313. It has been found that a given volume or quantity of distilled rain water at a given temperature always weighs the same. Hence, a cubic inch of distilled rain water has been adopted as the standard of weight.

314. The U. S. standard unit of weight is the Troy pound of the Mint, which is the same as the Imperial standard pound of Great Britain, and is determined as follows: A cubic inch of distilled water in a vacuum, weighed by brass weights, also in a vacuum, at a temperature of 62° Fahrenheit's thermometer, is equal to 252.458 grains, of which the standard Troy pound contains 5760.

5760 =
7000

=

-

315. The U. S. Avoirdupois pound is determined from the standard Troy pound, and contains 7000 Troy grains. Hence, the Troy pound is $768 144 of an avoirdupois pound. But the Troy ounce contains 5750 480 grains, and the avoirdupois ounce 7000 437.5 grains; and an ounce Troy is 480 437.5 = 42.5 grains greater than an ounce avoirdupois. The pound, ounce, and grain, Apothecaries' weight, are the same as the like denominations in Troy weight, the only difference in the two tables being in the divisions of the ounce.

=

STANDARD SETS OF WEIGHTS AND MEASURES.

317. A uniform set of weights and measures for all the States was approved by Congress, June 14, 1836, and furnished to the

States in 1842. The set furnished consisted of

A yard.

A set of Troy weights.

A set of Avoirdupois weights.

A wine gallon, and its subdivisions.

A half bushel, and its subdivisions.

318. State Sealers of Weights and Measures furnish standard sets of weights and measures to counties and towns.

A County Standard consists of

1. A large balance, comprising a brass beam and scale dishes, with stand and lever.

2. A small balance, with a drawer stand for small weights.

3. A set of large brass weights, namely, 50, 20, 10, and 5 lb. 4. A set of small brass weights, avoirdupois, namely, 4, 2, and 1 lb., 8, 4, 2, 1, 1, and oz.

5. A brass yard measure, graduated to feet and inches, and the first foot graduated to eighths of an inch, and also decimally; with a graduation to cloth measure on the opposite side; in a case. 6. A set of liquid measures, made of copper, namely, 1 gal., gal., 1 qt., 1 pt., pt., 1 gi.; in a case.

7. A set of dry measures, of copper, namely, bu., 1 pk., § pk. (or 1 gal.), 2 qt. (or gal.), 1 qt.; in a case.

ENGLISH MEASURES AND WEIGHTS.

GOVERNMENT STANDARDS.

319. The English act establishing standard measures and weights, called "The Act of Uniformity," took effect Jan. 1, 1826, and the standards then adopted, form what is called the Imperial System.

320. The Invariable Standard Unit of this system is the same as that of the United States, and is described in the Act of Uniformity as follows: "Take a pendulum which will vibrate seconds in London, on a level of the sea, in a vacuum; divide all that part thereof which lies between the axis of suspension and the center of oscillation, into 391393 equal parts; then will 10000 of those parts be an imperial inch, 12 whereof make a foot, and 36 whereof make a yard."

STANDARD OF EXTENSION.

321. The English Standard Unit of Measures of Extension, whether linear, superficial, or solid, is identical with that of the United States, (309).

STANDARDS OF CAPACITY.

322. The Imperial Standard Gallon, for liquids and all dry substances, is a measure that will contain 10 pounds avoirdupois weight of distilled water, weighed in air, at 62° Fahrenheit, the barometer at 30 inches. It contains 277.274 cubic inches.

323. The Imperial Standard Bushel is equal to 8 gallons or 80 pounds of distilled water, weighed in the manner above described. It contains 2218.192 cubic inches.

STANDARDS OF WEIGHT.

324. The Imperial Standard Pound is the pound Troy, which is identical with that of the United States Standard Troy pound of the Mint, (314.)

325. The Imperial Avoirdupois Pound contains 7000 Troy grains, and the Troy pound 5760. It also is identical with the United States avoirdupois pound.

TABLES.

326. The denominations in the standard tables of measures of extension, capacity, and weights, are the same in Great Britain and the United States. But some denominations in several of the tables are in use in various parts of Great Britain that are not known in the United States.

These denominations are retained in use by common consent, and are recognized by the English common law. They are as follows:

327. MEASURES OF EXTENSION.

18 inches

45 inches or

5 quarters of the standard yard}

make 1 cubit.

66 1 ell.

NOTE.-The cubit was originally the length of a man's forearm and hand; or the distance from the elbow to the end of the middle finger.

Pipes of wine are of different capacities, as follows:

110 wine gallons make 1 pipe of Madeira.

Barcelona,
Vidonia, or

Teneriffe.

Sherry.

8 bushels of 70 pounds each make 1 quarter of wheat.

36

heaped measure,

66

1 chaldron of coal.

NOTE.-The quarter of wheat is 560 pounds, or of a ton of 2240 pounds.

NOTE.-The English quarter is 28 pounds, the hundred weight is 112 pounds, and the ton is 20 hundred weight, or 2240 pounds.

FRENCH MEASURES AND WEIGHTS.

GOVERNMENT STANDARDS.

331. The tables of standard measures and weights adopted by the French Government are all formed upon a decimal scale, and constitute what is called the French Metrical System.

332. Invariable Standard Unit. The French metrical system has, for its unit of all measures, whether of length, area, solidity, capacity, or weight, a uniform invariable standard, adopted from nature and called the métre. It was determined and established as follows: a very accurate survey of that portion of the terrestrial meridian, or north and south circle, between Dunkirk and Barcelona, France, was made, under the direction of Government, and from this measurement the exact length of a quadrant of the entire meridian, or the distance from the equator to the north pole, was computed. The ten millionth part of this arc was denominated a métre, and from this all the standard units of measure and weight are derived and determined.

STANDARDS OF EXTENSION.

333. The French Standard Linear Unit is the métre. 334. The French Standard Unit of Area is the Are, which is a unit 10 métres square, and contains 100 square métres.

335. The French Standard Unit of Solidity and Capacity is the Litre, which is the cube of the tenth part of the métre.

STANDARD OF WEIGHT.

336 The French Standard Unit of Weight is the Gramme, which is determined as follows: the weight in a vacuum of a cubic decimetre or litre of distilled water, at its maximum density, was called a kilogramme, and the thousandth part of this was called a Gramme, and was declared to be the unit of weight.

NOMENCLATURE OF THE TAELES.

337. It has already been remarked, (331), that the tables are all formed upon a decimal sca e. The names of the multiples and divisors of the Government standard units in the tables are formed, by combining the names of the standard units with prefixes; the names of the multiples being formed by employing the prefixes deca, (ten), hecto, (hundred), kilo, (thousand), and myria, (ten thousand), taken from the Greek numerals; and the names of the divisors by employing the prefixes deci, (tenth), centi, (hundredth),