232 EXPERIMENTS relating to 
ftocking-wire, and after laying one end of it upon the half- 
crown piece which fupported the leg, we with the other end of 
the wire preffed the doubled tinfoil againft the half-crown piece 
which fupported the loins, and found, that in{tantly convulfions 
were produced in the mufcles of the thigh and leg. 
WHEN the tinfoil was paffled around both {ciatic nerves, 
both legs were convulfed, although the half crown piece was 
placed under one of the legs only. Thefe experiments were 
tried more than an hour after the fpinal marrow had been cut 
acrofs, with the fame fuccefs. 
In another frog, in which the fpinal marrow was not divided, 
we found the fame means produce the fame e'lects upon the 
legs, but did not obferve, that the mufcles above the tinfoil 
in the trunk or fore-legs were affected. 
WueEn the touches were quickly repeated, the motions feem- 
ed to become, by degrees, lefs vigorous, but did not ceafe af- 
ter repeating them often, even where the fpinal marrow had - 
been divided tranfverfely. 
On the toth of November, I profecuted the fubject farther 
by the following experiments : 
ExPERIMENT I. 
Arter cutting off the hind legs of a living frog, I laid bare 
the upper part of its fpinal marrow, and furrounded it with tin- 
foil; and in another frog, after laying bare the brain, | thruft 
into it a bit of tinfoil. 1 then placed one half crown piece be- 
tween the table and the body of the frog, oppofite to the tin- 
foil, and another half crown piece between the table and the 
lower part of the trunk of the animal, and, on applying the 
wire, as before, | found convulfions produced in the fore-legs 
and body. Gold had nearly the fame effet as filver ; but the 
3 convulfions 
