158 Prof. A. de la Rive’s Memoir of 
of analysis for the ordinary chemical decompositions in which 
electricity does not assist. Lastly, he gives the name of elec- 
trolytes to those compound bodies which are capable of being 
decomposed by the electric current. 
After this preliminary and general study of the subject, Fa- 
raday enumerates the results which he obtained by submitting 
to electrochemical decomposition a very great number of com- 
pounds, some of them simple acids or simple bases, others sa- 
line combinations. He dwells particularly on the secondary 
ts often manifested in these decompositions, especially in 
the case of aqueous solutions, in which decomposition of the 
water and of the substance dissolved takes place at the same 
time. But the essential point of his researches is the law at 
which he arrived as to the definite nature of electrochemical 
we give the name of voltameter to the very simple apparatus 
which holds acidulated water destined to be decomposed by the 
current, and by means of which the volume of gases set free 
by this current in a given time may be exactly measured. 
The second principle, that the same quantity of electricity 
quantities of tin, lead, chlorine, hydrogen and —— which 
are chemically equivalent. Then, rising from the effect to the 
cause, he comes to the conclusion that there is a perfect equali 
ity 
poses a hody and that which 
is generated by the which produces the direct 
