532 
MR. F. GOTCH ON THE ELECTROMOTIVE PROPERTIES 
present, and his results are thus explained (41). If he did so, then his results were 
not observed at Arcachon with winter Torpedoes; but perhaps a future investigation 
will disclose them. 
Thus a strip of Torpedo, 60 mm. long, gave the following results, when the rheotome 
was arranged so as to break the galvanometer circuit for good at *05" after the passage 
of the induction shock, the after-effect being thus excluded from observation :— 
The two readings were always taken in the same direction, the galvanometer wires 
being reversed so as to admit this in the case of both ( + ) and ( —) shocks. 
Five Groves in Primary Coil. 
Deflections. 
Secondary coil, 10 centims.( + ) C. 440 
)i u .... ( ) ,, 435 
0 centim.( + ) G-. _j_ 185 
,, ,, . . . . ( ) ,, 185 
In another preparation experiments were carried out upon the whole organ and a 
cut strip. 
Two Groves in Primary Circuit. 
Secondary coil, 5 centims., G. 
Whole organ. 
55 . 
„ 0 centim., G. y^y 
55 55 55 
Cut strip, 0 centim., '0055 R. . . 
Deflections. 
(-) 420 
( + ) 410 
(-) 408 
! ( + ) 415 
(-) 412 
( + ) 622 
(-) 626 
( + ) 492 
(-) 483 
An important fact must be taken into consideration in this connection, since 
it is not inconsistent with so-called “irreciprocal” conduction, namely that the 
( + ) induction current is more efficacious than the (—) one in producing the 
after-effect. How far this distinction is related to the difference of behaviour 
of the nerve itself to ascending and descending exciting currents can only be decided 
by experiments specially contrived to bear upon the subject. It is, however, more 
satisfactory to approach the whole subject of irreciprocity from the point of view 
of irreciprocal excitation than from that of irreciprocal conduction. Such experiments 
will have to deal with the production of states of anelectrotonus and catelectrotonus 
in the organ. They were not attempted in the present research. 
There can, however, be little doubt that the organ is thrown, by the passage of an 
induction shock through its substance, into a state of prolonged excitation which 
slowly passes off, and, if this is so, then the rapid development of a large nerve- 
organ response must, if sufficiently intense, be itself capable of throwing the tissue 
