37. Reduce 175lb. into grains. Ans. 1008000.

38. How many pounds are there in 201600 grains? Ans. 35.

APOTHECARIES' WEIGHT.

50. The Apothecaries compound their medicines by this weight, but never use it for buying or selling: the pound and ounce are exactly the same as the pound and ounce troy; but the smaller divisions in this weight have the advantage in point of convenience, where great accuracy is required *.

8 drams

12 ounces

gr. Э
20= 1 3

60= 3=13

1 ounce. 3. 480= 24= 8= 1 t

1 pound. t. 5760=288=96=12=1

39. In 10 113 73 29 19gr. how many grains?

OPERATION.

33 gr.

10 11 7 2 19
12

131 ounces.
8
1055 drams.
3

3167 scruples.
20

Ans. 63359 grains.

Explanation.

Beginning at the pounds, I multiply by 12, and take in the 11 for ounces; these I multiply by 8, and take in the 7 for drams; the drams I multiply by 3, and take in the 2 for scruples; which latter I multiply by 20, and take in the 19 for grains.

* Drugs of every description are bought and sold by Avoirdupois weight. Physicians, as well as their learned brethren the lawyers, conceal their secret from the vulgar under the disguise of abbreviated Latin; a practice derived from the Schoolmen: thus, in their prescriptions,

cochleare, a spoonful.

congius, a gallon.

pugil, as much as can be held between the thumb

and two fingers.

manipulus, a handful.

quantum sufficit, a sufficient quantity.

a scruple.

a dram.

an ounce.

a pound.

41. In 63359 grains, how many pounds? Ans. 10 113 73 29 19gr.

42. In 27 73 23 19 4gr. how many grains? Ans. 159024.

AVOIRDUPOIS WEIGHT.

51. Avoirdupois weight is used for almost all kinds of merchandise; it seems to have been adopted for the purpose of giving sufficient weight in selling commodities of a coarse and drossy nature, a pound in this weight being equal to 14oz. 11dwt. 16gr. troy nearly'.

1 Avoirdupois weight began to be used for butchers' meat only about the end of the 15th century, and became a legal weight for that purpose by the 24 Henry VIII. by degrees its use was extended to all kinds of coarse and heavy merchandise, so that now all kinds of grocery and chandlery wares, meat, bread, corn, tallow, pitch, tar, turpentine, iron, brass, copper, lead, tin, &c. &c. are weighed by Avoirdupois weight.

A pound Troy equals 13oz. 23dr. nearly Avoirdupois, and an ounce Troy is about loz. dr. Avoirdupois: also, an ounce Avoirdupois equals 18dwts. 5gr. Troy; 175 pounds Troy = 144 pounds Avoirdupois; 175 ounces Troy 192 ounces Avoirdupois; consequently the Troy pound is less, and the ounce greater, than the pound and ounce Avoirdupois.

=

The name Avoirdupois is derived from the French avoir, to have, and du poids, weight.

Some commodities for which this weight is used have denominations peculiar to themselves; as the following.

43. In 1t. 2cwt. 3qr. 4lb. how many pounds?

OPERATION.

t. cwt. gr. lb.

1 2 3 4
20

22 cwt.
4

91 qr.

28

732 182

Ans. 2552 lb.

Explanation.

I multiply the ton by 20, and take in the 2, which gives cwts. these I multiply by 4, and take in the 3, which gives quarters; these I multiply by 28, and take in the 4 for pounds.

64

96

many cwt.?

112 10cwt. Oqr. 26lb. 12oz. 7dr. Ans.

26 lb.

135 128

Explanation.

In the first operation, I divide drams by 16, and the quotient is 18348 ounces; these I di12 ounces. vide by 16, and the quotient is 1146 lbs.; these I divide by 28, and the quotient is 40 quarters; these I divide by 4, and the quotient is 10 cwt.; this, with O over in quarters, 26 in pounds, 12 in ounces, and 7 in drams, constitutes the an

7 drams.

Or thus. dr. 29357513

16473393

16

28

4 73393 1

1834810

4587 3

}

dr.

swer.

In the second operation, instead of the two sixteens, I divide twice, by 4 X 4, and instead of 28, by 7 x 4, which makes short division of it: the remainders are calculated by Art. 39. 12 oz. in Division.

45. In 32cwt. how many pounds? Ans. 3584. See Example 43.

46. In 10752 pounds, how many cwt.?

Divide by 28 and 4.

47. In 14cwt. how many drams?

Ans. 96.

Ans. 401408.

Multiply by 4, 28, 16, and 16.

48. In 200704 drams, how many ewt. Ans. 7.

Divide by 16, 16, 28, and 4.

49. In 2cwt. 3qr. 4lb. 5oz. 6dr. how many drams? Ans. 79958. 50. In 11t. 12cwt. 3qr. 14lb. how many ounces? Ans. 417312. 51. In 12760lb. how many tons? Ans. 5t. 13cwt. 3qr. 20lb. 52. In 4t. 3cwt. 2qr. 1lb. how many drams? Ans. 2394368.

52. LONG MEASURE.

In estimating the contents of magnitudes, different measures are employed; some are measured by their length only, some by their length and breadth conjointly, and some by their length, breadth, and thickness conjointly.

Long Measure" is that which measures any one of these dimensions, being applied to distance only.

m Long Measure, which is that from whence all the other measures are derived, owes its origin to the length of a grain of barley: three grains of sound ripe barley being taken out of the middle of the ear, well dried, and laid end to end in a row, were considered as an inch, which in this measure is called the measuring unit. As the length of the barley-corn cannot be fixed, so the inch according to this method will be uncertain; but to remedy this inconvenience, there are standard measures as well as weights kept in the Exchequer chamber, Guildhall, for the purpose of comparing the weights and measures used by dealers; this helps to secure the public from imposition and fraud, as the use of measures or weights less than the standard is prohibited by law. n The hand is used in measuring the height of horses.

• The foot is supposed to be taken from the length of the human foot.

The cubit is a measure used by the ancients, and often mentioned in their writings; it is supposed to have been originally taken from the length of that part of a man's arm between the point of the elbow and the extremity of the hand.

The yard is said to have been taken from the arm of King Henry I. in 1101.

The fathom is taken from the utmost extent of both arms, when stretched into a right line; it is applied to measuring mines, wells, pits, and depths, in general; also the length of ropes, &c.

• The length of the pole differs in different parts of England; in the neighbourhood of London it is 54 yards; in some counties it is 6, in Lancashire 7, and in Cheshire 8 yards.