the Angel 10s.; the Mark=13s. 4d.; the Pistole 16s. 10d.; the Moidore=27s.

OES. The present standard gold coin of Great Britain, consists of 22 parts pure gold, and 2 parts of copper.*

The weight of a Sovereign or £, is 5 pwts., 312 grains.

The standard silver coin consists of 37 parts of pure silver, and 3 parts of copper. The weight of a shilling is 3pwts. 15 grs.

In copper coin, 24 pence weigh 1 pound avoirdupois.

TROY WEIGHT.

249. Troy Weight is used in weighing gold, silver, jewels, liquors, &c., and is generally adopted in philosophical experiments.

OBS. 1. The abbreviation oz., is derived from the Spanish onza, which signifies an ounce.

2. The standard of Weights and Measures is different in different countries, and in different States of the Union. In 1834, the Government of the United States adopted a uniform standard, for the use of the several Custom-houses and other purposes.

250. The standard Unit of Weight adopted by the Government, is the Troy Pound of the United States Mint. It is equal to 22.794422 cubic inches of distilled water, at its maximum density, the barometer standing at 30 inches, and is identical with the Imperial Troy pound of Great Britain, established by Act of Parliament, in 1826.

OBS. The weights and measures in present use, were derived from very imperfect and variable standards. A grain of wheat, taken from the middle of the ear or head, and being thoroughly dried, was the original element of all weights used in England; it was thence called a grain. At first, a weight

QUEST. 249. In what is Troy Weight used? Repeat the Table? Obs. Do all the States have the same standard of weights and measures? 250. What is the standard unit of weight adopted by the Government of the United States? Note. When was Troy Weight introduced into Europe? From what was its name derived?

* Hind's Arithmetic; also, Hutton's Mathematics.

†The maximum density of water, according to Mr. Hassler, is at the temperature of -39-83 deg. Fahrenheit.

The Troy pound of the U. S. Mint, is an exact copy, by Captain Kater, of the British Imperial Troy pound. Report of the Secretary of the Treasury, March 3, 1831.

equal to 32 grains, was called a pennyweight, from its being the weight of the silver penny then in circulation. At a later period the pennyweight was divided into 24 equal parts instead of 32, which are still called grains, being the smallest weight now in common use.

Note.-Troy Weight was formerly used in weighing articles of every kind. It was introduced into Europe from Cairo in Egypt, about the time of the Crusades, in the 12th century. Some suppose its name was derived from Troyes, a city in France, which first adopted it; others think it was derived from Troy-novant, the former name of London.*

AVOIRDUPOIS WEIGHT.

251. Avoirdupois Weight is used in weighing groceries and all coarse articles; as, sugar, tea, coffee, butter, cheese, flour, hay, &c., and all metals except gold and silver.

Note. In weighing wool in England, 7 pounds make 1 clove; 2 cloves, 1 stone; 2 stone, 1 tod; 6 tods, 1 wey; 2 weys, 1 sack; 12 sacks, 1 last; 240 pounds, 1 pack.

OBS. 1. Formerly it was the custom to allow 112 pounds for a hundred weight, and 28 pounds for a quarter; but this practice has become nearly or quite obsolete. In buying and selling all articles of commerce estimated by weight, the laws of most of the States as well as general usage, call 100 pounds a hundred weight, and 25 pounds a quarter.

2. Gross weight is the weight of goods with the boxes, casks, or bags which contain them.

Net weight is the weight of the goods only.

252. The Avoirdupois Pound of the United States, is equal to 27.701554 cubic inches of distilled water, at the maximum density, and at 30 inches barometer. It is determined from the Troy Pound, by the legal proportions of 5760 grains, which con

QUEST.-251. In what is Avoirdupois Weight used? Repeat the Table? Obs. How many bounds were formerly allowed for a hundred weight? For a quarter? What is gross weight? Net weight? 252. How is the Avoirdupois pound of the United States determined?

*Hind's Arithmetic, Art. 224. Also, North American Review, Vol. XLV.

Reports of Secretary of Treasury, March 3, 1832: June 30, 1832. Also, Congressional Documents of 1833.

stitute the Troy pound, to 7000 grains Troy, which constitute the Avoirdupois pound. That is,

equal to 27-7274 cubic Fahrenheit, when the

OBS. 1. The British Imperial Pound Avoirdupois is inches of distilled water, at the temperature of 620 barometer stands at 30°. It is determined from the Imperial Troy pound, which contains 5760 grains, while the former contains 7000 grains.

2. Since the Troy pound of the United States is identical with the Troy pound of England, the Avoirdupois pound of the former must be equal to that of the latter; for both bear the same ratio to the Troy pound. But the English avoirdupois pound is said to contain 27.7274 cu. in. of distilled water, while that of the United States, according to Mr. Hassler, contains 27.701554 cu. in. This slight difference may be accounted for by the fact that the former was measured at the temperature of 62°, while the latter was measured at its maximum density, which is 39.83 degrees.

3. The standard of weight adopted by the State of New York, in 1827, is the avoirdupois pound, whose magnitude is such that a eubic foot of distilled water, at the maximum density, in a vacuum, will weigh 624 pounds, or 1000

ounces.

Note.-The term avoirdupois, is thought by some to be derived from the French avoir du poids, a phrase signifying to have weight. Others think it is from avoirs, the ancient name of goods or chattels, and poids signifying weight in the Norman dialect.*

APOTHECARIES' WEIGHT.

253. Apothecaries' Weight is used by apothecaries and physicians in mixing medicines.

OBS. 1. The pound and ounce in this weight are the same, as the Troy pound and ounce; the other denominations are different.

2. Drugs and medicines are bought and sold by avoirdupois weight.

QUEST.-253. In what is Apothecaries' Weight used? Recite the Table? Obs. To what are the apothecaries' ounce and pound equal? How are drugs and medicines bought and sold?

* President John Quincy Adams on Weights and Measures; also, Hind's Arithmetic.

LONG MEASURE.

254. Long Measure is used in measuring distances where length only is considered, without regard to breadth or depth. It is frequently called linear or lineal measure.

360 degrees make a great circle, or the circumference of the earth.

Note.--4 inches make 1 hand; 9 inches, 1 span; 18 inches, 1 cubit; 6 feet, 1 fathom.

In measuring roads and land, surveyors use a chain which is 4 rods long, and which is divided into 100 links. Hence, 25 links make 1 rod, and 7-22 inches make 1 link. This chain is commonly called Gunter's Chain, from the name of its inventor.

OBS. 1. The inch is commonly divided either into eighths or tenths; sometimes, however, it is divided into twelfths, which are called lines. Formerly the inch was divided into 3 barleycorns; but the barleycorn is not employed as a measure at the present day. The term barleycorn, is derived from a grain of barley, which was the original element of Linear Measure.

2. The terms rod, pole, and perch, from the French perche signifying a rod, are each expressive of the instrument, which was originally used as a measure of this length.

255. The standard Unit of Length adopted by the United States, is the Yard of 3 feet, or 36 inches, and is identical with the British Imperial Yard. It is made of brass, at the temperature of 62° Fahrenheit, from the scale of eighty-two inches prepared by Troughton, a celebrated English artist, for the survey of the Coast of the United States.

OBS. 1. The Imperial standard yard of Great Britain is determined from the pendulum which vibrates seconds in a vacuum, at the level of the sea, in

QUEST.-254. In what is Long Measure used? What is Long Measure sometimes called? Recite the Table? Obs. How are inches usually divided? What is the origin of the measure called barleycorn? Is this measure now used? 255. What is the standard unit of Length adopted by the United States?

Greenwich or London. This pendulum is divided into 391393 equal parts, and 360000 of these parts are declared, by act of Parliament, to be the standard yard, at the temperature of 62°; consequently, since the yard is divided into 36 inches, follows that the length of a pendulum vibrating seconds, under these circumstances, is 39.1393 inches.

The English yard is said to have been originally determined by the length of the arm of Henry I. King of England.

2. The standard of linear measure adopted by the State of New York, is the pendulum which vibrates seconds, in a vacuum, at Columbia College, in the city of New York, which is in the latitude of 40° 42′, 43′′. The yard is declared to be 1998 of this pendulum; hence, the length of the pendulum is 39.101688 inches, at the temperature of 32°. Should the standard yard ever be lost, it could be recovered by resorting to the preceding experiment.

CLOTH MEASURE.

256. Cloth Measure is used in measuring cloth, lace, and all kinds of goods, which are bought and sold by the yard.

OBS. Cloth measure is a species of long measure. Cloths, laces, &c., are bought and sold by the linear yard, without regard to their width.

SQUARE MEASURE.

257. Square Measure is used in measuring surfaces, or things whose length and breadth are considered without regard to height or depth; as, land, flooring, plastering, &c.

144 square inches (sq. in.) make 1 square foot,

9 square feet

marked sq. ft.

30 square yards, or

2724 square feet

Obs. Of what is

QUEST.--256. In what is cloth measure used? Repeat the Table.

cloth measure a species? What is the kind of yard by which cloths, laces, &c., are bought and sold? 257. In what is Square Measure used? Recite the Table.