GRAIN. In the common weights and measures of this country, a grain is the smallest weight now in use. It is of about the weight of a seed of wheat corn, and must therefore be considered rather as a theoretical aliquot part of a larger weight than as itself a proper standard of weight. By a statute of 1266, it was enacted that 32 grains of wheat, taken out of the middle of the ear, and well dried, should weigh a pennyweight, of which 20 should make an ounce, of which 12 should make a pound. Consequently the pound (troy) of this period consisted of 7680 grains, whereas that afterwards in use had only 5700. The reason was, that it became usual to divide the same pennyweight into 24 instead of 32 grains. The grain lost much of its importance by the introduction of the averdupois pound, of which it is not a constituent aliquot part. The ancient averdupois pound is variously stated at from 7009 grains to less than 7000, at which latter number it is now fixed bylaw.
The weight of one grain is obtained, for practical purposes, without difficulty, by weighing a thin plate of metal of uniform thickness, and cutting out by measurement such a proportion of the whole plate as should give one grain. But a much better plan is to
draw a given weight of ductile metal into very thin wire, and to cut from the wire that length which is the same proportion of the whole length as a grain is of the whole weight. In this way pieces of wire are obtained for chemi cal purposes which weigh only the thousandth part of a grain ; and even less weights might be obtained, if it were necessary.
Another popular use of the word grain is as a synonyme of corn; for a few statistical details concerning which we may refer to CORN TRADN.—Adding here, however, a later item, concerning the Corn Trade of 1850. In that year the grain or corn imported into Great Britain amounted to 7,069,435 quarters ; while the various kinds of flour and meal im ported were 3,873,908 cwts. Nearly half of the grain imported was wheat; and nearly all the meal was wheat-meal or flour.