1866.] 



Indications of Aiiimal Electricity, 



165 



of the fibres with the other kind. At any rate, the facts revealed by the 

 electroscope do not appear to be of doubtful significance, and the only 

 inference which I can deduce from them is that every part of the sur- 

 face of living nerve- tissue, natural or artificial, furnishes signs of the same 

 kind of electricity, and that the only electrical differences between one part 

 and another are nothing more than differences of degree. 



Fourth Series. — Experiments which furnish electroscojpic indications of 

 electricity in living muscular tissue. 



In this series of experiments the mode of proceeding was the same as 

 that adopted in the last series. 



Exjp. 1 7. — The piece of muscle examined in this experiment was cut out 

 of the sterno-niastoid of an ox a few moments after the animal had been 

 killed in the shambles, and every part of the surface was tested in turn, 

 and, except in some trifling difference in degree, the movements of the gold 

 leaves were in all cases indicative of the action of positive electricity = 6, 

 these movements being those of d. d. = 4 in the negative electroscope, and 

 those of i. d. = 8 in the positive electroscope. 



Exp. 18. — Here the sterno-mastoid of a sheep just killed in the ordinary 

 way in the shambles, furnished the material for experiment, and the result 

 was — no alteration in the divergence of the gold leaves in the negative 

 electroscope, and i. d. = 4 in the positive electroscope — a result showing 

 the action of positive electricity = 2 upon the electroscopes. 



Exp. 19. — In this instance the portion of muscle examined was taken 

 from the glutseus maximus of a donkey which had just been killed by 

 haemorrhage, and it was found that all parts of the surface indifferently 

 supplied indications of negative electricity = 1, the movements of the gold 

 leaves being those of i. d. = 1 in the positive electroscope, and i. d.= 3 

 in the negative electroscope. 



Exp. 20. — A piece of the left ventricle of the heart of a dog just dead 

 from haemorrhage was examined in this instance, and the only movements 

 of the gold leaves were those which are produced by the action of a body 

 electrically neutral, namely, i. d. = 2 in both electroscopes equally. 



Exp. 21. — Here the piece of muscle experimented upon was that used 

 in Exp. 17. Twelve hours had elapsed between the two experiments, and 

 rigor mortis had now fully set in, and the result showed that the positive 

 electricity which was present formerly was no longer present, the move- 

 ments of the gold leaves being simply those of i. d. = 2 in both electro- 

 scopes equally. 



With the exception of an experiment in which Professor Matteucci 

 incidentally states that he obtained signes de tension avec un condensa- 

 teur delicat " from one of his " muscular piles, " these experiments fur- 

 nish, so far as I know, the only electroscopic indications of the presence of 

 electricity in living muscular tissue — perhaps the very first really distinct 

 proofs of this fact. I have repeated these experiments several times on 



p 2 



