of England in 1797, the effect of increased note issues was only gradually felt, for the bank followed in the main a conservative policy. This was true also of the suspension by the Bank of France in 1870. On the other hand, during the suspension of specie payments in the United States in 1813, the banks issued notes recklessly and the depreciation was considerable. When the banks of the United States, on December 30, 1861, again suspended specie payments and the Government followed their example, the large issues of legal-tender notes caused a like result.
The resumption of specie payments is usually a slow and tedious process. The first step toward resumption is the gradual restriction of the paper issues; in the case of Government notes redemption is accomplished by the aid of taxation, while in the case of bank notes resumption occurs through pressure of the Government by taxation of excessive issues or by other means. The second step is to procure a fund of metallic money sufficient to meet probable demands for redemption. To effect this end the Government credit is usually called into requisition. The resumption of specie payments restores the convertibility of credit money, but does not destroy the money itself. It provides for the redemption in metallic money of such sums as may be presented, but not the compulsory redemption of the whole.
The financial history of the United States in the years succeeding the Civil War illustrates the process of resumption. The close of that war found the monetary circulation of the United States exclusively paper. Government issues, State bank notes, and national bank notes. Specie payments had been suspended since 1861, and a return to them seemed the first duty of financial policy. The fear of a contraction of the currency, however, made the first steps in this direction hesitating and uncertain. The gradual redemption of the United States notes, which in January, 1864, had stood at $449,000,000, undertaken under the law of April 12, 1866, had been arrested in February, 1868, when the amount stood at $356,000,000. In the financial troubles of 1873, the Secretary of the Treasury, upon somewhat dubious authority, had increased the volume, but by act of June 20, 1874, Congress stopped this increase when the issue had reached $382,000,000. The task of resumption was earnestly taken in hand early in 1875, when an act was passed providing for resumption on January 1, 1879. In its several provisions and as a whole the act was in the following years the object of repeated attack, but all efforts to repeal it failed. This law removed the limitation which had heretofore rested upon the aggregate issue of national bank notes. It provided, moreover, that as new notes were issued, United States notes to the extent of 80 per cent. of the new bank issues should be retired and canceled. Under this provision the volume of the legal-tender notes diminished by May 31, 1878, when this provision was repealed, to $345,000,000. The resumption act further authorized the Secretary of the Treasury, by the accumulation of surplus revenues and by the sale of bonds, to collect a supply of gold wherewith to resume. The amount to be collected and the amount to be maintained after resumption became a fact were left to his discretion. By the sale of bonds at favorable opportunities the Secretary had on hand on the day of resumption $140,000,000 in gold. The growing strength of the Treasury produced a diminishing premium on gold, and the first of January, 1879, passed off without the dreaded shock. Only a small amount of paper money was actually presented for payment. See Money.
SPECIES. See Classification of Animals; Evolution.
SPECIFICATION. In the law of patents, a technical description of the invention mentioned in an application for a patent, and when used without the word ‘claim’ it includes the claims or arguments of the inventor as to the novelty, usefulness, etc., of his invention. See Patent, and the authorities there referred to.
SPECIFIC GRAVITY (ML. specificus, specific, particular, from Lat. species, kind). The ratio between the weights of equal volumes of any substance and of some other, chosen as a standard. For solids and liquids the standard substance is water, for gases, air, or sometimes hydrogen. Since the volume of a given weight of a substance changes with temperature, it is necessary for exact determinations that the standard selected should be at a certain fixed temperature. Thus specific gravity is not the ratio of an equal volume of a given substance to water at any temperature, but only at the standard temperature which is selected, as described below. Likewise for a specific gravity determination to be of value the temperature of the substance at the time of making the measurement should be given. For gases not only the temperature, but the pressure must be mentioned. For many purposes the term density has replaced specific gravity, but the two are not synonymous. The density of a substance (at a given pressure and temperature) is the mass of that substance in a unit volume, provided it is homogeneous; otherwise it is the mass of a volume so small as to be homogeneous, divided by the volume. Thus density is an absolute term, expressing the quantity of a certain kind of matter in a given space, while specific gravity is merely relative, being in fact the ratio of the density of the substance to the density of the standard. The specific gravity of a gas or vapor is usually referred to air at the same pressure and temperature as that of the gas, but also frequently to hydrogen under like conditions. In terms of the latter it is equal to half the molecular weight of the gas. See Molecules—Molecular Weights.
The specific gravity of solids and liquids is variously referred to water at 4° C., 15° C., or 62° F., and sometimes still other temperatures. Specific gravities on these scales are respectively as 1.000045, 1.000913, 1.001180—the density of water at these temperatures being inversely as these numbers. The difference is obviously not of importance except for purposes of extreme accuracy. Density in the metric system is measured in grams per cubic centimeter (kilograms per liter). If a liter of water at 4° C. weighed exactly a kilogram, as was intended, the density of water at this temperature would be one and metric density and specific gravity referred to water at 4° C. would be identical. The density of water at this temperature is actually .999955, so that specific gravity referred to water at 4° is equal to density × 1.000045. Specific gravity referred to air at 0° C. and 76 centimeters pres-
