146 FUNDAMENTAL UNITS OF MEASURE. 



by "bringing the calculation of the principal affairs of life within the 

 arithmetic of every man who can multiply and divide,'" 



None will be more benefited personally by this action, and none can 

 aid more effectually to hasten it, than the distinguished body to which 

 this paper is respectfully submitted. If any argument in its favor were 

 needed, it \vould be suflftcient to cite the example of one department of 

 the great subject of engineering, namely, electrical engineering, which 

 is doubtless represented in some degree in this Congress. But, yester- 

 day a thing unknown, its beautifully simple units of measure and their 

 interrelations are as wings which have enabled it to outstrip those 

 that persist in carrying the dead weight of an unscientific and hope- 

 lessly bad system of metrology. 



UNITS OF ELECTRICAL MEASURE.* 



Within but little more than a decade practical applications of elec- 

 tricity have developed with a rajjidity unparallelled in the history of 

 modern industries. Many millions of dollars of capital are now in- 

 vested in the manufacture of machinery and various devices for the 

 prodnction and consumption of electricity. As it has now become 

 a commodity of trade, its nieasurement is a (juestion of the highest 

 importance, both to the jiroducer and consumer. Both the nomencla- 

 ture of electro-technics and the methods and instruments of measure 

 are excej^tionally precise and satisfactory, bnt there has been lacking, 

 up to the present time, the veiy important and essential element of 

 fixed and invariable units of measnre authoritatively adopted. Such 

 units have long been in use among scientific men, but the necessity for 

 the establishment and legalization of practical units for commercial 

 purposes became evident in the beginning of the recent enormous 

 development of the applications of electricity. 



To meet this universally recognized want, conferences and congresses 

 of the leading electricians of the world have been held at occasional 

 intervals, the first being the Paris Congress of 18S1. These assem- 

 blages have been international in their character, for it was wisely 

 determined in tlie beginning that the new units of measure should be 

 international and, indeed, universal in their api)lication. It was con- 

 venient to make them so, and it was important to thns facilitate in- 

 ternational interchange of machinery, instruments, etc. The United 

 States was represented by official delegates in the Congress of 1881, 

 and also in snbse<juent Congresses in 1881. 



The difficulty of the material representation of some of the units 

 of measure was so great at the time of holding these Congresses that 

 no satisfactory agreement as to all of them could be arrived at. Some 

 recommendations were made, but they at no time received the unani- 

 mous support of thoseinterested and were admitted by all to be tentative 

 in their character. During the past few years the advance of knowl- 



* Bulletin No. 30, U. S. Coast and Geodetic Survey. 



