224 PROFESSOR DANIELL ON THE ELECTROLYSIS OF SECONDARY COMPOUNDS. 
bining together, as in the local action, are respectively evolved at the zincode and 
platinode. The following diagrams may perhaps assist in explaining my notion of 
the origin and connection of the current. 
OP OP OP 1 (N + 6 O) H (N + 6 O) H (N + 6 O) PI 
B 
Let OP and (N + 6 0) H represent the two electrolytes on the opposite sides of 
the diaphragm A B before action ; after action has commenced they may be repre- 
sented thus : 
A 
O p7) PO p'TTn +6 0) H (N + 6 O) H+T+ 6 O) H 
B 
May I not ask, in conclusion, whether such a current does not again defy any ex- 
planation upon the contact theory? 
Believe me, dear Faraday, 
Very faithfully yours, 
Kings College, 
29 th April , 1840. 
J. F. Daniell. 
