Table 3. 



TABLES FOR CONVERTING U. S. WEIGHTS AND MEASURES. 



(2) METRIC TO CUSTOMARY. 



V>y the concurrent action of the principal governments of tlie world an International Bureau of Weights and 

 Measures has been established near P.iris. Under the direction of the International Committee, two ingots were cast 

 of pure platinum-iridium in the proportion of g parts of the former to i of the latter metal. From one of these a cer- 

 tain number of kilograrnmes were prepared, from the other a definite number of metre bars. These standards of 

 weight and length were intercompared, without preference, and certain ones were selected as International prototype 

 standards. The others were distributed by lot, in September, i8Sg, to the different governments, and are called 

 National prototype standards. Those apportioned to the United States were received in iSgo, and are kept in the 

 Office of Standard Weights and Measures in Washington, 1). C. 



The metric system was legalized in the United States in iS66. 



The International Standard Metre is derived from the Metre des Archives, and its length is defined by the dis- 

 tance between two lines at o° Centigrade, on a platinum-iridium bar deposited at the International Bureau of Weights 

 and Measures. 



The International .Standard Kilogramme is a mass of platinum-iridium deposited at the same place, and its 

 weight in vacuo is the same as that of the Kilogramme des Archives. 



The litre is equal to a cubic decimetre, and it is measured by the quantity of distilled water which, at its maximum 

 density, will counterpoise the standard kilogramme in a vacuum, the volume of such a quantity of water being, as 

 nearly as has been ascertained, equal to a cubic decimetre. 



Smithsonian Tables. 



ID 



