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or of a nearly similar weight under another (6.) name, seem stronger proofs that this is legal weight, than the mere silence of the written laws is of the contrary.

Be this as it may, it is in such general use with us, that, on the principle of popular convenience, its higher denominations, at least, must be preserved. It is by the avoirdupois pound and ounce that our citizens have been used to buy and sell. But the smaller subdivisions of drachms and quarters are not in use with them. On the other hand, they have been used to weigh their money and medicine with the pennyweights and grains troy weight, and are not in the habit of using the pounds and ounces of that series. It would be for their convenience, then, to suppress the pound and ounce troy, and the drachm and quarter avoirdupois; and to form into one series the avoirdupois pound and ounce, and the troy pennyweight and grain. The avoirdupois ounce contains 18 pennyweights 5 grains troy weight. Divide it, then, into 18 pennyweights, and the pennyweight, as heretofore, into 24 grains, and the new pennyweight will contain between a third and a quarter of a grain more than the present troy pennyweight; or, more accurately, it will be to that as 875 to 864-a difference not to be noticed, either in money or medicine, below the denomination of an ounce.

But it will be necessary to refer these weights to a determinate. mass of some substance, the specific gravity of which is invariable. Rain water is such a substance, and may be referred to everywhere, and through all time. It has been found by accurate experiments that a cubic foot of rain water weighs 1000 ounces avoirdupois, standard weights of the exchequer. It is true that among these standard weights the committee report small variations; but this experiment must decide in favor of those particular weights, between which, and an integral mass of water, so remarkable a coincidence has been found. To render this standard more exact, the water should be weighed always in the same temperature of air; as heat, by increasing its volume, lessens its specific gravity. The cellar of uniform temperature is

best for this also.

Let it, then, be established that an ounce is of the weight of a cube of rain water, of one-tenth of a foot; or, rather, that it is the thousandth part of the weight of a cubic foot of rain water, weighed in the standard temperature; that the series of weights of the United States shall consist of pounds, ounces, pennyweights, and grains; whereof

24 grains shall be one pennyweight;

18 pennyweights one ounce;

16 ounces one pound.

COINS.

Congress, in 1786, established the money unit at 375.64 troy grains of pure silver. It is proposed to enlarge this by about the third of a grain in weight, or a mill in value; that is to say, to establish it at 376 (or, more exactly, 375.989343) instead of 375.64 grains; because it will be shown that this, as the unit of coin, will link in system with the units of length, surface, capacity, and weight, whenever it shall be thought proper to extend the decimal ratio through all these branches. It is to preserve the possibility of doing this, that this very minute alteration is proposed.

We have this proportion, then, 875 to 864, as 375.989343 grains troy to 371.2626277; the expression of the unit in the new grains.'

Let it be declared, therefore, that the money unit, or dollar of the United States, shall contain 371.262 American grains of pure silver.

If nothing more, then, is proposed, than to render uniform and stable the system we already possess, this may be effected on the plan herein detailed; the sum of which is: 1st. That the present measures of length be retained, and fixed by an invariable standard. 2d. That the measures of surface remain as they are, and be invariable also as the measures of length to which they are to refer. 3d. That the unit of capacity, now so equivocal, be set'tled at a medium and convenient term, and defined by the same invariable measures of length. 4th. That the more known terms in the two kinds of weights be retained, and reduced to

one series, and that they be referred to a definite mass of some substance, the specific gravity of which never changes. And 5th. That the quantity of pure silver in the money unit be expressed in parts of the weights so defined.

In the whole of this no change is proposed, except an insensible one in the troy grain and pennyweight, and the very minute one in the money unit.

II. But if it be thought that, either now, or at any future time, the citizens of the United States may be induced to undertake a thorough reformation of their whole system of measures, weights and coins, reducing every branch to the same decimal ratio already established in their coins, and thus bringing the calculation of the principal affairs of life within the arithmetic of every man who can multiply and divide plain numbers, greater changes will be necessary.

The unit of measure is still that which must give law through the whole system; and from whatever unit we set out, the coincidences between the old and new ratios will be rare. All that can be done, will be to choose such a unit as will produce the most of these. In this respect the second rod has been found, on trial, to be far preferable to the second pendulum.

MEASURES OF LENGTH.

Let the second rod, then, as before described, be the standard of measure; and let it be divided into five equal parts, each of which shall be called a foot; for, perhaps, it may be better generally to retain the name of the nearest present measure, where there is one tolerably near. It will be about one quarter of an inch shorter than the present foot.

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Superficial measures have been estimated, and so may continue to be, in squares of the measures of length, except in the

and acres. is 100 feet.

case of lands, which have been estimated by squares, called roods Let the rood be equal to a square, every side of which This will be 6.483 English feet less than the English (7.) rood every way, and 1311 square feet less in its whole contents; that is to say, about one-eighth; in which proportion, also, 4 roods will be less than the present acre.

MEASURES OF CAPACITY.

Let the unit of capacity be the cubic foot, to be called a bushel. It will contain 1620.05506862 cubic inches, English; be about one-fourth less than that before proposed to be adopted as a medium; one-tenth less than the bushel made from 8 of the Guildhall gallons; and one-fourteenth less than the bushel made from 8 Irish gallons of 217.6 cubic inches.

Let the bushel be divided into 10 pottles;

Each pottle into 10 demi-pints;

Each demi-pint into 10 metres, which will be of a cubic inch each.

Let 10 bushels be a quarter, and

10 quarters a last, or double ton.

The measures for use being four-sided, and the sides and bottoms rectangular, the bushel will be a foot cube.

The pottle 5 inches square and four inches deep;

The demi-pint 2 inches square, and 24 inches deep;
The metre, an inch cube.

WEIGHTS.

Let the weight of a cubic inch of rain water, or the thousandth part of a cubic foot, be called an ounce; and let the ounce be divided into 10 double scruples:

The double scruple into 10 carats;

The carat into 10 minims or demi-grains;

The minim into 10 mites.

Let 10 ounces make a pound;

10 pounds a stone;

16 stones a kental;

10 kentals a hogshead.

COINS.

1

Let the money unit, or dollar, contain eleventh-twelfths of an ounce of pure silver. This will be 376 troy grains, (or more exactly, 375.989343 troy grains,) which will be about a third of a grain, (or more exactly, .349343 of a grain, more than the present unit. This, with the twelfth of alloy already established, will make the dollar or unit, of the weight of an ounce, or of a cubic inch of rain water, exactly. The series of mills, cents, dimes, dollars, and eagles, to remain as already established (8.)

The second rod, or the second pendulum, expressed in the measures of other countries, will give the proportion between their measures and those of the United States.

Measures, weights and coins, thus referred to standards unchangeable in their nature, (as is the length of a rod vibrating seconds, and the weight of a definite mass of rain water,) will themselves be unchangeable. These standards, too, are such as to be accessible to all persons, in all times and places. The measures and weights derived from them fall in so nearly with some of those now in use, as to facilitate their introduction; and being arranged in decimal ratio, they are within the calculation of every one who possesses the first elements of arithmetic, and of easy comparison, both for foreigners and citizens, with the measures, weights, and coins of other countries.

A gradual introduction would lessen the inconveniences which might attend too sudden a substitution, even of an easier for a more difficult system. After a given term, for instance, it might begin in the custom-houses, where the merchants would become familiarized to it. After a further term, it might be introduced into all legal proceedings, and merchants and traders in foreign commodities might be required to use it in their dealings with one another. After a still further term, all other descriptions of people might receive it into common use. Too long a postponement, on the other hand, would increase the difficulties of its reception with the increase of our population.

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