126 RESPONSE IN THE LIVING AND NON-LIVING 
platinum—side by side, it will be seen how essentially 
similar they are in every respect.' 
This reversion to normal is seen to have appeared in 
a pronounced manner after rapidly continuous stimula- 
tion, in process of which the modified molecular condi- 
tion must in some way have reverted to the normal. 
Being desirous to trace this change gradually taking 
place, I took a platinum wire cell giving modified 
Ye 
responses, and obtained a series of records of effects of 

Fic. 78.—THE GRADUAL TRANSITION FROM ABNORMAL TO NORMAL RESPONSE 
IN PLATINUM 
The transition will be seen to have commenced at the thirdand ended at the seventh, 
counting from the left. 
individual stimuli continued for a long time. In this 
series, the points of transition from modified response to 
normal will be clearly seen (fig. 78). 
| In order to explain the phenomena of electric response, some physio- 
logists assume that the negative response is due to a process of dissimilation, 
or breakdown, and the positive to a process of assimilation, or building up, 
of the tissue. The modified or positive response in nerve is thus held to be 
due to assimilation ; after continuous stimulation, this process is supposed 
to be transformed into one of dissimilation, with the attendant negative 
response. 
How arbitrary and unnecessary such assumptions are will become evi- 
dent, when the abnormal and norma] responses, and their transformation 
from one to the other, are found repeated in all details in metals, where 
there can be no question of the processes of assimilation or dissimilation. 
