PROCEEDINGS 



OF 



THE ROYAL SOCIETY 



''A Research into the Elasticity of the Living Brain and 

 the Conditions governing the Recovery of the Brain after 

 Compression for short Periods."* By A. G. LEVY, M.B. 

 (London). Communicated by Professor V. HORSLEY, 

 F.R.S. Received February 21, Read March 15, 1894. 



(From the Laboratory of the Pathological Department of University College, 



London.) 



A. Object and Method of the Research,. 



1. Introduction. This piece of work was undertaken at the sugges- 

 tion of Professor V. Horsley, who devised the apparatus employed, 

 and to whom I am indebted for advice and suggestions. 



In view of the great frequency of compression of the brain as a 

 pathological condition, it seems very advisable to attempt to obtain 

 knowledge of some of the elementary factors conditioning the physical 

 changes in the brain substance due to mechanical pressure. 



The general plan adopted was (a) to compress the living brain (i.e., 

 the brain substance plus lymph and circulating blood) by a given 

 weight for a given time, to measure the amount of direct compression, 

 and, after removal of the pressure, to measure the elastic recoil ; 

 (b) to investigate the influence upon the recoil of varying conditions 

 of the vascular and respiratory systems. 



Finding in an early stage of the investigation that the elasticity of 

 the brain is very far from being perfect, I was further led to investi- 

 gate the conditions, vascular, &c., which favoured more complete 

 recovery of the brain surface to its normal level, especially after 

 periods of prolonged compression. 



The following, therefore, are records of an investigation of the 



* Towards the expenses of this research a grant was made by the British Medical 

 Association on the recommendation of the Scientific Grants Committee of the 

 Association. 



VOL. LVIII. B 



