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the ounce avoirdupois. Avoirdupois weight is used for coarse and bulky goods of every description, and all the ordinary purposes of trade and commerce.

Measures. The standard unit of lineal ineasure, in this country is the yard, all other denominations being either multiples or aliquot parts of the yard. By 5 Geo. IV. c. 74, it is defined that “The straight line or distance between the centres of the two points in the gold studs in the brass rod, now in the custody of the clerk of the House of Commons," whereon the words and figures Standard yard, 1760, are engraved, shall be, and the same is hereby declared to be, the original and genuine standard of that measure of length or lineal extension called a yard; and that the same straight line or distance between the centres of the said two points, &c., the brass being at the temperature of 620 of Fahrenheit's thermometer, shall be, and is hereby denominated the Imperial Standard yard, and shall be, and is hereby declared to be, the unit or only standard measure of extension."

The same Act further declares that “ If at any time hereafter the said imperial standard yard shall be lost, or shall be in any manner destroyed, defaced, or otherwise injured, it shall be restored by making, under the directions of the Lords of the Treabury, a new standard yard, bearing the proportion to a pendulum vibrating seconds of mean time, in the latitude of London, in a vacuum, and at the level of the sea, of 36 inches to 39.1393 inches."

It is here assumed that the laws of nature operate at all times with strict uniformity and the distance between the axis of suspension and centre of oscillation of a pendu. lum vibrating seconds of mean time, under the conditions above stated, is declared to be 39.1393 imperial inches, or 3 imperial feet and 3:1393 inches. If this distance or unit of length had been accurately determined before any of the national measures were established and bronght into general use, it would have supplied a certain and convenient standard, and all distances would in that case have been expressed in mul. tiples or fractions of such unit. But since the national measures and their units werə fixed long prior to the determination of this distance, it became necessary to express the latter in the measures already known; and therefore instead of its being denoted by 1, or unity, which had previously been appropriated to the foot, it was represented in terms of the foot, viz., as 39.1393 inches. The unit of measure is not only important as affording a basis tor every species of measurement, but serves also as the element from which is deduced the unit of weight. The weight of 27.7015 cubic inches of distilled water, equal exactly to one pound avoirdupois, is taken as the standard, while this quantity of water is determined from the unit of length; that is, the determination of it reaches back to the length of a pendulum which will vibrate seconds in the latitude of London.

With reference to the method prescribed by law for the restoration of the standard yard measure, it should be stated, however, that considerable doubt is now entertained by men of science as to the system of standards derived from nature being susceptible of that extreme accuracy which was formerly attributed to it. The relation beiween the yard measure and the pendulum, as assigned in the Act, has be 'n proved to be incorrect, on account of the neglect of certain precautions in determining the length of the pendulum, which subsequent experiments have shown to be indispensable, and besides the true length of the seconds' pendulum is one of those physical constants which it is possible to determine only within certain limits of error, very narrow indeed, but still too wide for the purpose in question. In this, as in many other instances, the evil has arisen from legislating too much. All that is required is, that two very fine points be struck in a strong rod of platinum, or a block of cast iron, at any convenient distance apart, and to declare that the distance betw en those points at a given temperature of tre metal, shall be the standard of measure, and that so many parts of such standard shall constitute the yard or unit; all the rest may be saf-ly left to experimental philosophers, and mathematical instrument makers.t

The standard from which, considered as the unit, all measures of capacity, both for liquid and dry goods, are to be computed, is the imperial standard gallon, containing

* See Note to preceding page.

+ See Article Measure, in Brande's Dictionary of Science, Literature, and Art.

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101bg, weight avoirdupois of distilled water, at the temperature of 62 degrees of Fahrenheit's thermometer, the barometer being at 30 inches (5 Geo. IV. c. 74, 8. 6). It will be seen that the capacity of the gallon is determined immediately by weight, and remotely by the standard of length, as follows. The pound avoirdupois contains 7,000 grains, and it is declared by law, that a cubic inch of distilled water (temperature 62° Fahrenheit, barometer 30 inches), weighs 252-458 grains. Hence the contents of the imperial gallon must be 277:274 cubic inches; for as,

gre.
grs.

cub. in. cub, in.
252:458 70,000 (= 10lbs. avoir.)

1 277.274.

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By the 6 Geo. IV. c. 58, s. 6, it is declared that, "In all acts relating to the Excise, whenever and for whatever purpose any gallon is mentioned, it shall be deemed a gallon, imperial standard gallon measure ; and whenever any other measure by name is mentioned, it shall be deemed to be a measure formed of the usual number of gallons, each such gallon being imperial gallon standard measure; and all duties, allowances, drawbacks, payments, accounts, and reckonings of or relating thereto, under any law of Excise, shall be made and kept according to such imperial standard gallon measure only, or some multiple, part, or proportion thereof."

Standard weights and measures verified under the direction of the treasury, are to be deposited in the office of the Chamberlain of the Exch-quer at Westminster, ard verified copies thereof sent to such places as the Treasury shall direct, and other copies deposited in counties, cities, &c., under the direction of the magistrates. (5 Geo. IV. c. 74, 89. 11, 12.) All copies of such weights and measures, verified and stapped at the Exchequer, are to be deemed legal. (5 & 6 Wm. IV. c. 63, s. 4.)

In all cases in which excise duties are chargeable by actual weight, traders are required to keep just scales and weights for the use of officers, and penalties are imposed upon traders keeping unjust scales or weights, or using any contrivance which may impede the officer in taking a true account. (10 Geo. Ill. č. 44, ss. 1, 2; 26 Geo. III. c. 77, s. 8; &c., &c.)

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N.B._"Grs.” stands for grains weight; "dwts." for pennyweights; "oz." for ounces; “lbs." for pounds; “drs." for drachms; "qrs." for quarters; and “cwts." for hundredweights.

Although by the 5 & 6 Wm. IV. c. 63, s. 11, it is declared that “14 lbs. avoirdupois shall be 1 stone, and 8 such stones, 1 hundred weight," yet a great diversity of values is given to the stone weight in the various parts of the United Kingdom at the present time.

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The pole and the furlong are now very rarely used, distances from place to place being reckoned in miles and gards.

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Table No. 5.- MEASURE OF CAPACITY, FOR ALE, BEER, &0.

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Table No. 6.-MEASURE OF CAPACITY, FOB WINE, SPIRITS, &c.

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Puncheong

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It should be noted that the barrel, hogshead, &c., differ in content, according as they are used for beer or wine.

Table No. 7.-MEASURE OF CAPACITY, FOR CORN AND DRY GOODS.

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Table No. 8.-DIMENSIONS OF THE IMPERIAL MEASURES OF CAPACITY IN INCHES

AND DECIMALS, AND ALSO IN INCHES AND THE NEAREST FRACTIONS.

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Inches. Inches. Inches.
8.0000 18.7892 19.5000
8 1818 191
6.3496 14.9130 15.4771

141. 155
5.0396 | 11.8364 12.2842
515 113 122
4.0000 9:3946 97500
4

9 3.1748 7:4565 7.7385 316

Peck .......

Inches.
6.0000
6
4.7622
41
3.7797
33
3.0000

.2820

*2239
1
•1776
To
1410

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Half-gallon..

2.3811
29
1.8998
13

770
2-5198 5.9182 6.1421
23 51% 6}

•1119

Quart

MONEY. In the United Kingdom, money-accounts are kept in pounds, shillings, pence, and farthings. The symbols or marks used for these are £, for pounds ; s, for shillings ; and d, for pence; y, and sometimes the letter f, is used for farthings, or quarters of a pound. The pound used to be represented by a Bank.note, value 208.; it is now replaced by a coin, called a sovereign; there was formerly another gold coin, called a guinea, the sub-divisions of which were the half-guinea, and the seven-shillingpiece. The value of the guinea was 21s. Though this latter coin has gone out of circulation, it is still customary to call 21.. a guinea.

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Gold and silver coins always contain a certain proportion of alloy, which is fixed by law. In order to express the fineness of gold, the pound Troy is supposed to be divided into 24 parts, called carats, and the carat into 4 grains, called carat grains. Thus, the carat is equal to 240 grains Troy, and the carat grain to 60 grains Troy. Standard gold—that from which coins are made-is said to be “22 carats fine," which means that out of one pound Troy of such gold, 22 carats are pure metal and 2 carats alloy.

The fineness of English standard gold is denoted, therefore, by the fraction 11.

The fineness of silver is expressed in oz. and dwts. British standard silver, or that of which coins are made, is 11 oz. 2 dwts. fine ; that is, a pound Troy of such silver contains 11 oz. 2 dwts. of pure metal, and 18 dwts. of alloy; consequently, the fineness of silver may be represented by the fraction . Sometimes, the fineness of gold and silver is stated in terms of the excess or defect of pure metal in the specimen over or under the standard. This excess or defect is known as the betterness or worseness. Thus, if gold be reputed as “1 carat, 3 grains better," it is understood to contain so much more pure gold in a pound Troy than standard gold contains, or in other words, to be 23 carats, 3 grains fine. Silver reported as “6 dwts. worse," contains only 216 dwts. of the pure metal in a pound Troy.

In exchanges and the valuation of money, the alloy is considered of no value.

A pound Troy of standard gold is coined into 44; guineas, or 40lbs. into 1869 sovereigns. From this it follows that the weight of a sovereign 123.27447 grains, in which the weight of pure gold is 113.00159 grains. Hence also the Mint price of standard gold is £3 178. 10d. per ounce troy. No charge is made in the English Mint for coining gold bullion.

Gold and silver are not alloyed in coinage from motives of economy, but for convenience of workmanship, and for the purpose of rendering the coin harder and more durable.

Gold coins are allowed by law to pass under the full weight, an allowance of a little more than half a grain being made for the diminution of weight caused by use. Thus a sovereign passes for its full value, provided it reaches the weight of 5 dwts. 2 grs.

Articles of plate in gold are allowed to be of standard y-that is, 22 carats fine; but in watch cases this degree of fineness is not permitted, the standard for them being 18 carats fine, so that one-fourth of the material is alloy. The "Hall

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