Brackett and Young—Edison’s Dynamometer, ete. 475 
instead of both external and internal, as in Z. anatina. 
Art. LXV.— Notes of Haperiments upon Mr. Edison's Dyna- 
mometer, Dynamo-machine and Lamp; by Professors C. F. 
Brackett and C. A. Youne, of Princeton, N. J. 
and he was requested by Mr. Edison to make an independent 
po 
accuracy is claimed for our results—though we beiieve them 
to be substantially correct—that is to say, within one or two 
per cent. 
We first made a comparison of Mr. Edison’s dynamometer 
with the well known Prony, the latter being driven migties 
the former precisely as the dynamo-machine was, during the 
