And let all measures of capacity of dry subjects be stricken
with a straight strike.
WEIGHTS.
There are two series of weights in use among us; the one called
avoirdupois, the other troy.
_In the Avoirdupois series:_
The pound is divided into 16 ounces;
The ounce into 16 drachms;
The drachm into 4 quarters.
_In the Troy series:_
The pound is divided into 12 ounces;
The ounce (according to the subdivision of the apothecaries)
into 8 drachms;
The drachm into 3 scruples;
The scruple into 20 grains.
According to the subdivision for gold and silver, the ounce is
divided into twenty pennyweights, and the pennyweight into
twenty-four grains.
So that the pound troy contains 5760 grains, of which 7000 are
requisite to make the pound avoirdupois; of course the weight of the
pound troy is to that of the pound avoirdupois as 5760 to 7000, or as
144 to 175.
It is remarkable that this is exactly the proportion of the
ancient liquid gallon of Guildhall of 224 cubic inches, to the corn
gallon of 272; for 224 are to 272 as 144 to 175. (4.)
It is further remarkable still, that this is also the exact
proportion between the specific weight of any measure of wheat, and
of the same measure of water: for the statute bushel is of 64 pounds
of wheat.
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