288 On the DevelopjnentqfEledricityby Muscular Contraction. 



The entire results of the experiments were — 



Extracted by water 27*24< 



Extracted by muriatic acid 37" 70 



In the ash of the residuary carbonaceous mass 35"06 



The whole constituents were — 10000 



Chloride of sodium . 0-19 



Potash 35-16 



Soda 0-4.2 



Lime 4-47 



Magnesia .... 4-05 



Peroxide of iron . . 0-61 



Sulphuric acid . . . 0-08 



Phosphoric acid . . 54-74 



99-72 



These results agree very well with those obtained by Mit- 

 scherlich. 



Yeast is therefore a meroxidic substance, and possesses most 

 analogy with flesh in regard to its inorganic constituents. 



XXXVI. Notice respecting Du Bois Reymond's Discovery of 

 the Development of Electricity by Muscular Contraction. 

 By Prof. Buff of Giessen"^. 



THE remarkable observation made by Du Bois Reymond, 

 that an electric current can be excited by muscular con- 

 traction, has been called in question by Messrs. Despretz and 

 Becquerel, who did not succeed in obtaining favourable results 

 on repeating the experiment f. Under these circumstances it 

 may prove of interest to describe a few experiments which I 

 have made with a better result. 



The galvanometer employed was constructed by Kleiner of 

 Berlin ; it had 3000 convolutions of a copper wire one-fifth of a 

 millimetre in thickness. The extremities of this wire were 

 connected, according to Du Bois Reymond's directions, with 

 strips of platina cut out of the same sheet of metal. Each 

 strip dipped permanently into a vessel containing a saturated 

 solution of common salt. Notwithstanding this precaution it 

 was found impossible to obtain an absolute and permanent 

 uniformity of the two strips. However, on immersing the 

 fingers in the salt water, in general only a faint current, which 



* From Liebig's Annalen der Chimie for June 1849. 



•f A notice of M. Du Bois Reymond's experiments appeared in the Phi- 

 losophical Magazine for July 1849, p. 543; Messrs, Becquerel and Des- 

 pretz's observations on the same subject will be found at pp. 53, 55 of the 

 present volume.— Ed. P/iil. Mag. 



