the Discharge of a Leyden Jar. 167 
AB, fig. 8, which has been measured; and as we are ignorant 
of the true curve, it might be objected that the real curve might 
just as well’ be supposed to be like that given with dotted line. 
There is, however, experimental evidence to show that this is 
not the case ; for on this supposition, the blurring of the image 
would begin to be visbile far earlier, i. e., with lower velocities 
than has been observed. In point of fact, the image remains 
visibly as distinct as with a stationary mirror till a certain stage, 
a8 much time. 
Duration of the first act, with a Leyden jar having a coating of 
114-4 square inches. 
ers were employed in connecti 
coarsest of the three lamp-black’ plates; but when the mirror 
urns i 
= duration of this first act was 000000175 of a second, or sees 
nd the same striking 
our times as great as with the small jar a 
distance 
New York, June 29th, 1871. 
