OF THE ELECTRICAL ORGAN OF TORPEDO MARMORATA. 
529 
The following experiment, made upon a strip 45 millims. long and 5 millnns. broad, 
illustrates this point. Organ-current, + '009 11. 
Six Groves in Primary Circuit. 
Secondary coil, 16 centims. ( + ) G. without shunt 
,, :, 15 ,, ,, ,, 55 
.. .. 14 .. ,, i, ,, 
J? 
•n 
(-) 
( + ) 
(-) 
15" readings. 
}> 15" readings. 
15" x’eadings. 
The effect is thus dependent upon the intensity of the current, which must vary 
with the dimensions of the preparation, so that an induction current which produces 
no effect upon a large thick block of tissue will produce an effect upon a long narrow 
strip cut from this block. Such a thin strip can be procured most readily from the 
organ of a small Torpedo, and it was with a preparation of this kind that the largest 
effects were observed. Thus a strip 15 millims. long, and only a little more than a 
millimetre wide, gave the following result:— 
Six Groves in Primary Coil. 
Deflections. 
Secondary coil, 8 cm. ( + ) G. j-r_. 
? J 
n 
+ CO 
+ 240 
+ 100 
+ 20 
I 
>• 15" readings. 
As in the case of the nerve-organ response, so here the effect is more pronounced 
when the strip is cut from a vigorous Torpedo, but it may still be obtained in a strip 
which has been left for 24 hours. The same strip as that used for tire preceding 
experiment gave the following results when examined at intervals of 15 and 
24 hours :—- 
Six Groves in Primary Coil Circuit. 
Slowly subsiding. 
Secondary coil, 8 cm.(+ ) G. x \, . + 600 
jj >> ..( —) ,, • + 250 
,, ,, 24 hours later, 8 cm. ( + ) . . . 0 
,, ,, ,, „ 5 cm. (-f ) G. all in + 545 
55 55 55 5 5 5 5 ( ) 1 5 160 
MDCCCLXXXVII.—B. 3 Y 
