The drop varies from 0.02 to 0.1 cubic centi metre and is not a fixed unit, but is convenient for use in dispensing very small quantities of liquids. It is not subdivided and its size de pends upon the liquid and the method of ping. The ordinary form of drop pipette of the ophthalmologist delivers drops of about a half rated States The United States fluid dram ((i0 minims) is equal to one-eighth United States fluid ounce, its %ohmic differing from the volume of one avoirdupois drain of water, from the volume of one apothecaries' dram of water (by weight), and is about 4 per cent larger than the fluid dram in use in Great Britain. It is about 4 cubic centimetres, or an average teaspoonful, and is denoted by the symbol f3.
The United States fluid ounce (480 United States minims) is the 1-16 part of the wine pint and has a volume of about 1.8 cubic inches. It differs from the British unit of the same name as well as from the volume of the avoir dupois ounce of water and the troy or apothe caries' ounce of water. Other measures of less definite character are often found convenient, such as the teaspoonful, dessertspoonful. table spoonful, wineglassful and teacupful. They do not contain exactly the quantities usually given arbitrarily, but more exactly the common spoon fuls contain the following quantities: A table spoonful, 5 fluid drams or 20 cc.; a dessert spoonful, 2 fluid drams or 10 cc.; a teaspoonful, 60 minims or 5 cc.
Dry Measures.— The dry measures in gen eral use in the United States bear no direct relation to the liquid measures of this country or Great Britain. The following are the ordinary units of dry measures: One bushel = 4 pecks = 32 dry quarts =64 dry pints. The fundamental unit is the Winchester bushel, a unit abandoned by England in 1824. The Winchester bushel had a capacity of 2,178 cubic inches. In the United States the name Winchester has been attached to the London bushel with a volume of 2,150.42 cubic inches and is about 69 cubic inches or 3 per cent smaller than the Imperial bushel of Great Britain — a proportionate difference exist ing in the subdivisions of the bushel. Conflict ing State laws render difficult an adequate state ment of the status of the °bushel* in this coun try. Although the standard Winchester bushel contains 2,15042 cubic inches. Nebraska has established 2,150 cubic inches as the volume of a legal bushed for that State, and other States have made similar changes. Several States adopted the old ale or milk gallon as the capacity of the dry gallon. this being about S per cent larger than the corresponding unit derived from the Winchester bushel. Moreover, special bushels have been legally established in many States for particular products, such as the char coal bushel, which in Connecticut is 2,748 cubic inches, in Colorado 2.500 cubic inches, in Kansas
2 564 cubic inches, in Pennsylvania 2,571 cubic inches and in Minnesota 2,419.5 cubic inches (or basket). In Vermont "one bushel and three-quarters of a peck' are "deemed a bushel of charcoal, lime, or ashes.' In some places five pecks constitute a bushel of "screened lump coal.' A lime bushel in Minnesota is 2,688 cubic inches. In Pennsylvania, however, it is equal to the Winchester bushel, although the coke bushel is 2,648 cubic inches. In the adjoining State of Ohio the coke bushel is 2.6M cubic inches. In Idaho, the bushel of fruit is defined as 2.564 cubic inches and in Missouri as 2,680 cubic inches. Some States require, furthermore. *heaped measure,' others 'struck measure,' the heap sometimes being required to be gas high as the article will admit!' and elsewhere "as high as may be without special effort or de sign.* and in still other cases, as in Connecticut, the heaped bushel is definitely fixed as 2.564 cubic inches. The many objections to buying and selling agricultural products by volume. such as the difficulty of detecting error or fraud, the variation in the size of the heap, the ease of packing short quantity in a given volume, the effects of expansion, moisture, or shaking and the general uncertainty of estimates of quanuty based upon volume early led to the practice now quite general, of defining the bushels as definite weights for the different com modities. Unfortunately the matter was left to the several States with the result that the lack of uniformity in legislation and custom has introduced considerable confusion. Not only do the weights fail to equal the true volume of one Winchester bushel but even for the same com modity and in adjoining States the values are widely at variance. In at least two cases the size of the bushel varies with the time of the year. For a few commodities like wheat and hard coal, the standard weight is fairly general — but for such commodities as fruits and vege tables there is but little uniformity. The values of the various bushels of apples vary by about 10 per cent and for beans and charcoal about the same proportion, the legal weights of the bushel of gooseberries or beets by about 20 per cent and for cranberries 17 per cent, for sweet potatoes and buckwheat the variation is al:out 28 per cent in range. The °bushel' has in fact become merely a name for a miscellaneous group of units varying from State to State and differ ing for the various commodities, sometimes as in at least two cases, changing with the time of the year. The uncertainty is confusing to trade and precludes the compilation of accurate statis tics based upon so variable and ambiguous a term.