038 



III. Finally my attention was given to the nerve of the subcutaneous 

 mnscle. Nahrich ^) testifies that by irritation of this norve, in addition to 

 contraction of the cutaneous muscle, also pain-symptoms are brought 

 forth, whilst after the sectioning of this nerve, the sensibility of the 

 skin had diminished. I have not been able to verify this latter fact. It 

 is not to be doubted moreover that e.q. an isolated root-area, if either 

 the isolated root or the peripherical branches have been cut through, 

 becomes entirely and completely insensible, whilst the nerve of the 

 cutaneous muscle remains iiilact. It is iherefore probable that this 

 nerve does not contribute to the sensibility of the skin. Nevertheless 

 I can confirm the statement of Nahrtch, that after its having been 

 cut through, irritation of the central end proves painful. It may be 

 that Ihe muscular sensibility plays a part in producing these symp- 

 toms of pain. 



Chemistry. — ''The AJlotropy of Cadmium." lY. By Prof. Ernst 

 Cohen and W. D. Helderman. 



(Communicated in the meeting of September 26, 1914), 



The electromotive tjehavimir of Cadmitim. II. 



1. Up to the present we ha\e only directed attention to the 

 electromotive behaviour of «- and y-cadmium; the iS-modification has 

 not been mentioned hitherto. It w ill be treated in the foUow^ing lines. 



2. It may be remembered that a number of cells constructed 

 according to the scheme: 



Gd 



electrolylically 

 deposited 



Solution of 

 cadmium sulphate 



Gd-amalgam 



12.5 percent 



hy weight. 



had an E.M.F. of 0.050 Volt at 25°.0, whilst the E.AI.F. of others 

 was only 0.047 Volt at the same temperature. (The cells were 

 reproducible within 0..5 millivolt). 



3. Now we were struck by the fact that when constructing a 

 large number of these cells we often got cells wdjich had an E.M.F. 

 of 0.048 Volt at 25°.0. 



The E.M.F. of cells which originally had an E.M.F. of 0.050 Volt 

 at 25°.0, spontaneously decreased till the value 0,048 Volt was reached. 

 After this their E.M.F. remained constant. 



4. The conclusion was plain that the cells giving 0.048 Volt might 



1) L. c. p. 95—96. 



