FUNDAMENTAL UN1T« OF MEASURE. 145 



their conipaTison, can be secured by iiecepting" the iuteruatioiial proto- 

 types as the fuiidaniental standards of k^iigtli and mass. It was doubt- 

 less the intention of Congress tliat this slionhl be done when the inter- 

 national metric convention was entered into in 1875; otherwise there 

 would be nothing gained from the annual contributions to its support 

 wliich the Government has constantly made. Such action will also 

 have the great advantage of putting us in direct relation in our weights 

 and measures with all civilized nations, most of whi<!h have adopted 

 the metric system for exclusive use. The practical effect upon our cus- 

 tomary weights and measures is, of course, nothing. The most care- 

 ful study of the relation of the yard and tlie meter has failed, thus far, 

 to show that tlie relation as defined by Congress in the act of 186(5 is in 

 error. The pound as there dehned, in its relation to the kilogram, dif- 

 fers from the imperial pound of Great JJritaiu by not jnore than 1 part 

 in 1()(>,0(H), an error, if it be so called, which utterly vanishes in com- 

 parison with the allowances in all ordinary transactions. Only the 

 most refined scientific research will demand acloser api)roximation, and 

 in scientific work the kilogram itself is now universally used, both in 

 this country and in England.* 



"In view of these facts, and the absence of any material normal 

 standards of customary Aveights and measures, the ottice of weights 

 and measures, with the approval of the Secretary of the Treasury, will 

 in the future regard the international prototype meter and kilog:ram 

 as fundamental standards, and the customary units, the yard and the 

 pound, wall be derived therefrom in accordance with the act of July 28, 

 18G0. Indeed, this course has been practically forced upon this office 

 for several years, but it is considered desirable to make this formal 

 announcement for the information of all interested in the science of 

 metrology or in measurements of precision. 



"T. V. Mendenhall, 

 '' tSnperintcHdent of l^iandanl Wehjht.'i and Measures, 



"Api)roved: 



"J. G. Carlisle, 



^'- tSecretari/ o/'llie Treasuni. 



"April 5, 181)3." 



As a result of this action, our fundameutal units of length and mass 

 are now the new international prototype meter and kilogram ineserved 

 by the International Bureau of Weights and Measures, near Paris, and 

 our metrology is in touch with that of the civilized world. This is the 

 second great step toward complete emancii)ation from the "brain- 

 wearying, intellect-destroying" system Avith which we have so longbeeu 

 burdened, and let us hope that the time is not far distant when the 

 desire of the author of the Declaration of Independence will be realized 



* Reference to the act of 1866 results in the establisliment of tlie following equa- 

 tions : 



:;i()()0 

 1 yard = oi.o-- metei . 



1 pound iivoirdiiiiois = ., o^./. kilo. 



A more precise value of the English pound avoirdupois iSf,.,,,,,.7,lvilo., differing 



from tlie above by about 1 part in 100,000, but the r(iuatioii established by law is 

 sutticiently accurate for all ordinary coiivcrsious. 



As already stated, in work of high i)rccisiou the kilogram is now all but univer- 

 sally used and no conversion is required. 

 SM 93 10 



