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animal. Moreover the latent period had considerably increased and 
amounted to about 0.015 second. A comparison of the curves with 
those of the electric phenomena of the eye can, in my opinion, not 
be made, as the string of the galvanometer in my experiments had 
a very slight tension, and the curves consequently would require 
much rectification, in order to indicate the oscillations of the current 
that occur in reality. 
For the latent period Ermruoven and Joruy (lc) found for the 
frog’s eye as the smallest value 0.01 second, moreover they report 
that for the stronger irritations the latent period is considerably 
shorter than for the feebler. 
Perhaps there is some connection between the very short latent 
period, found in my experiments, and the exceedingly strong irritation 
which the impulsive sound of the report is for the experimental animal. 
Received by the microphone the report seemed to give an amplitude 
of oscillation of the string when brought into circuit with the 
secondary chain, forty times greater than a very strong flute-tone 
(a*—a*). 
I could however when blowing this flute and likewise with the 
sound of a clock, observe an oscillation of the string, when it was 
connected with the nervus acusticus of the experimental animal. 
The oscillation was very slight 1—2 mm. and appeared to remain 
constant during the flute-tone. 
With the cavia it was utterly impossible for me to reach the 
nervus acusticus operatively. With the rabbit I could reach the 
nervus acusticus through the roof of the hindmost skuil-cavitv, 
by cutting away part of the cerebellum. By cauterization the violent 
hemorrhage had to be stopped. With a blunt hook the medulla was 
a little removed, and a platinum electrode was placed at a distance 
of  !/,-em. into the medulla oblongata. Now I could likewise 
register by photography an oscillation, though not so strong as at 
the stabbing experiments with the cavia, it was of about equal strength 
as the oscillation that the string shows, when the stabbing electrodes 
are applied to the rabbit. 
There is still a third method for observing electric phenomena of 
the nervus of a cavia or a rabbit. Of two unpolarisable electrodes, 
one was placed in the porus acusticus internus, the other on an 
indifferent spot of the hindmost skull-cavity. 
This was done under strong ether narcosis, the skull having been 
widely opened, and the whole mass of brain removed. In the dying 
animal very distinct electric currents were still observed in the nervus 
acusticus when the report struck the ear. As has already been remarked 
