506 
MR. F. GOTCH OR THE ELECTROMOTIVE PROPERTIES 
This change was subsequently found to be due to the high temperature of the room 
(20° C.) affecting that of the preparation. The experiment showed that it was possible 
to obtain with the instrument very sharp differences, with small differences in time, 
amounting to only two"- 
It was now necessary to see if the same would hold good of a cut piece of organ 
with nerve attached, a nerve-organ preparation. A large fish, 48 cm. X 30 cm., 
was selected, and the brain destroyed. The largest electrical nerve (the 2nd) was then 
prepared from its exit from the skull to its entry between the gill clefts. A great 
sector of organ, comprising the distribution of this nerve, was then made by two 
clean cuts with a razor through, the skin and the organ in the direction of the 
columns, the cuts reaching from the median to the outer border of the organ. The 
mass of separated organ measured 40 millims. in thickness at its median edge; this, 
therefore, represents the length of the columns at this point. It was fixed on a 
vertical board, and led off by cushions of saline kaolin similarly placed on its dorsal 
and ventral surfaces. The fish had been caught the night before the experiment, and 
the temperature of the organ was still very low, only 5° C. 
The block of tissue gave the usual “organ-current/’ = + '0052 R., which 
subsided slowly during the experiment. The nerve was excited 6 centims. from its 
point of entry into the organ by the break of two Groves in the primary coil. 
No response to the passage of the induction shock was observed until the secondary 
coil w 7 as pushed up to 8 cm., v hen a response of + 105 G. occurred. On pushing 
the coil to 5 cm., the response increased to -f- 350 G. y 0 -. 
Closure . 
-015"-*02 ,/ 
■ 02 "- 0225 " 
•0225"--027o" 
•0275"--0335" 
Deflection .... 
0 
0 
+ 70 G. m 
+ 150 G. t V 
+ 260 G. T V 
Closure . 
•0335"-0385" 
•0385”--0435" 
•0435"--05" 
Deflection .... 
+ 220 G. -w 
+ 15 G. yV 
+ 3 G. T V 
The temperature of the room subsequently affected the time relations of the 
response, as one hour afterwards the response was found to begin earlier. 
Galvanometer closure . 
•0T'-015" 
•015"--0165” 
•0165"--018" 
Deflection. 
0 
+ 15 
+ 150 
