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December 14, 1854. 



The LORD WROTTESLEY, President, in the Chair. 

 Robert Mallet, Esq., was admitted into the Society. 

 The following communications were read : 



I. "The Physical Theory of Muscular Contraction." By 

 CHARLES BLAND RADCLIFFE, M.D., Licentiate of the 

 Royal College of Physicians, Assistant-Physician to the 

 Westminster Hospital, and Lecturer on Materia Medica. 

 Communicated by CHARLES BROOKE, Esq., F.R.S. Re- 

 ceived November 18, 1854. 



The theory set forth in this paper is, that muscle is prevented from 

 contracting by the several vital and physical agencies which act as 

 stimuli upon muscle, volition, nervous influence, blood, electricity, 

 light, heat, and the rest, and that contraction happens on the cessa- 

 tion of stimulation, by virtue of the operation of that universal prin- 

 ciple of attraction which belongs to muscle in common with all 

 matter, and, so happening, that it is a physical phenomenon of the 

 same nature as that contraction which takes place in a bar of metal 

 on the abstraction of heat. 



This theory is supported by various arguments, some of which 

 are now stated for the first time. It is argued : 



(a.) That nervous influence cannot cause muscular contraction, 

 (1) because the degree of innervation, as measured by the supply of 

 nerves, is inversely related to the tendency to contraction ; (2) be- 

 cause contraction does not take place so long as the nerve gives 

 evidences of electricity (Du Bois Reymond); (3) because, in some 

 instances at least, contraction does not happen so long as the nerve 

 gives evidences of "irritability" for contraction is not caused by 



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