OFFICE OF STANDARD WEIGHTS AND MEASURES. AND MEASURES-CUSTOMARY TO METRIC. scale belonging to this office, whose length at 59.62° Fahr. conforms to the British yard. of the Mint. It is of brass of unknown density, and therefore not suitable for a by direct comparison. The British Avoirdupois pound was also derived from the Avoirdupois in use in the United States is equal to the British pound Avoirdupois. WASHINGTON, D. C., January, 1890. By Permission of T. C. MEN TABLE FOR CONVERTING U. S. WEIGHTS By the concurrent action of the principal governments of the world an Inter the direction of the International Committee, two ingots were cast of pure plati From one of these a certain number of kilogrammes were prepared, from the other tercompared, without preference, and certain ones were selected as International ments, and are called National prototype standards. Those apportioned to the The metric system was legalized in the United States in 1866. The International Standard Metre is derived from the Metre des Archives, platinum-iridium bar deposited at the International Bureau of Weights and Meas The International Standard Kilogramme is a mass of platinum-iridium de gramme des Archives. The liter is equal to a cubic decimetre of water, and it is measured by the quan ard kilogramme in a vacuum, the volume of such a quantity of water being, as OFFICE OF STANDARD WEIGHTS AND MEASURES. AND MEASURES-METRIC TO CUSTOMARY. national Bureau of Weights and Measures has been established near Paris. Under num-iridium in the proportion of nine parts of the former to one of the latter metal. a definite number of metre bars. These standards of weight and length were inprototype standards. The others were distributed by lot to the different governUnited States are in the keeping of this office. and its length is defined by the distance between two lines at o° Centigrade, on a ures. posited at the same place, and its weight in vacuo is the same as that of the Kilo tity of distilled water which, at its maximum density, will counterpoise the standnearly as has been ascertained, equal to a cubic decimetre. |