1302. ] 
aStion of artificial ele€tricity from the 
neighbourhood of an eleétrical machine, 
as above related, feems to fupport this 
opinion. On the tranfition of a fpark 
from the conduétor of the machine inte an- 
other conductor that is near it, the equi- 
librium. of electricity in the f{urrounding 
air is fuddenly difturbed ; and if this con- 
ductor is attached toa nerve or mufcle, 
an irritation and contraction of the mufele 
is excited as long as there remains omit 
any vitality. Under the fame cireum- 
ftances, no contractions are produced by 
the {park of the Leyden phial, becaufe 
the equilibrium -of eleétricity in the fur- 
rounding air is not difturbed by ir. 
Extra from a Letter of Profeffor 
LICHTENBERG, to Mr. Gren, in ‘his 
Fournal der Phyfik. Vol. VI. p.. 414.—It 
contains an account of Volta’s experiment 
with the tongue; the fenfation remaining 
on the tongue is compared to a feald of 
this organ. bi) 
_ Beytrage zur nakern Kenntnifs der 
Thierifchen Ele@ricitai—i.e.’ Contribu- 
tions to a nearer Knowlédge of Animal 
Electricity, by ES" J. ScHMUCK, 1792, 
p- 77, 8vo. Mannheim, for Schwan and 
Gotz. We find in this publication nothing 
that aniwers the title of it; and the only 
merit which we can allow to it, confifts in 
its having made this fubje&t more known 
inGermany, and by that means occafioned 
more accurate inquiries about it. To the 
fame end has contributed 7. F. Acker- 
mann’s Vorlaufige Bekanntmachung—i. e. 
Preliminary Account of Important Phe- 
nomena, from the late(t Phyfiological Ex- 
periments on the Nerves, in No. 68 of the 
Salzburg Medical and Chirurgical Ga- 
‘zette of the year 1792. 
Cary Caspar Creve Beytrage zu 
Galvani’s Verfuchen uber die Krafte der 
Thierijchen Electricitdt auf die Bewegung 
~der Mujfkeln—i. e. Contributions to Gal- 
vani’s Experiments on the Effeéts of Ani- 
mal Electricity upon’ Mufcular Motion, 
1793): pe 104, 8vo. Frankfort, and 
Leipzig, for Stahet’s widow. The au- 
thor draws the following corollaries from 
the experiments, partly made by Mr. 
Sommering, which are related in this pub- 
lication. It appears that, ift, the ftimu- 
lus difcovered by Mr. Galvani is not an 
animal nervous electricity. 2d, For pro- 
ducing this ftimulus, we need only coat 
the nerve with tin-foil, and touch thenerve 
and the tin-foil with a filver coin; and the 
nerve may be irritated at the place where 
it iffues trom the brain or fpinal-marrow, 
or where it is inferted into the mufcle, 
from which gonvulfions will equally fol- 
Hiftorical Statement of Galvanifin. 
133 
low. 3d, The convulfions continue as * 
long as the animals remain warm, and 
they become weaker in proportion as the 
natural heat decreafes, at the ceflation of 
which the convulfions likewife begin te 
ceafé. 4th, By means of this ftimulus . 
we may dilcover, whether or not nerves 
penetrate into a mufcle and other parts 3 
an idea, on which the opinion of Mr. 
Behrends is grounded, tliat the heart is 
properly not provided with nerves. 4th, 
The beft metals for making the experi- 
ment are tin-foil and filver; brafs, gold, 
iron, lead, &c. are‘not fo good; water, 
glafs, and other bodies are not fit for the 
experiment. 6th, The Galvanic fiimulus 
extends itfelf in the nerves and mutcles 
only beneath the coating, and never atts 
either fideways or upwards, 1. e. above 
the coating. 7th, The experiment caz 
be oftener and longer repeated with cotd- 
blooded animals, than with warm-blood- 
ed, becaufe the former do not lofe ther _ 
natural heat fo foon as the latter, or be~ 
caufe their mufcles can beara greater lofs 
of heat without being’ deprived of their 
property of moving. 8th, This ttimulus 
acts not only more viclently than any other, 
but alfo in a more lafiing manner, and fs 
neither -deftroyed by negative or pofi- 
tive electrical ftrokes. gth, On coating 
the nerve with gold-leaf, no convulfiens 
enfue; nor likewifeé’ when we place the 
tin-foil at fome dif&ance from the nerve, 
and ‘touch it and the nerve with filver at 
the fame time. roth, No convulfions are 
produced if, after having tied the nerve 
and’ ‘coated it above the ligature, we place 
on filver the coating and that part of the 
nerve which is above the ligature; but 
on touching the nerve ‘and coating below 
the ligature, the mufcles will be immed{- 
ately convulfed. When a coated nerve 
is cut off fore lines beiow the coating, 
and when the part that is cut off is placed 
on another nérve, which ts beneath’ this, 
on touching the coating with filver, com- 
motions will follow. On placing a coated 
nerve upon filver, without moving it, no 
contractions will appear; but as foon as 
the coating and nerye are moved on the 
filver, the contraGtions immediately enfue. 
Both kinds of eleétricity, that which is 
obtained from glafs, and that produced 
by putting fealing-wax into a negative 
ftate, muft be very confiderable in de- 
gree, before they are able to caufe any 
contractions on being applied to the 
nerves, The Galvanic experiment may. 
be repeated with ‘the fame frogs during 
eight, twenty-eight, thirty, and thirty-fix 
hours. The mufcles are put in motion by 
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