354 Dr, W. Marcet on the Nutrition of 



unless the presence of these channels be admitted. That such 

 a nutritive material really exists must be acknowledged, as 

 (Quain's ^Elements of Anatomy/ vol. ii.) "the capillaries des- 

 tined for the proper tissue of the muscle form among the fibres 

 a fine network with narrow oblong meshes, which are stretched 

 out in the direction of the fibres .... none of the capillary 

 vessels enter the sarcolemma or proper sheath of the fibre.^' 

 There must consequently be a material intermediate between 

 blood and tissue, reaching every particle of the tissue to be 

 nourished j and with this object in view, there must exist proper 

 means for the thorough distribution of this material. I have 

 shown {Bibl. Universelle, Feb. 1865), by a very simple obser- 

 vation of a physical nature, and without the use of a microscope, 

 that a system of channels ramifies through muscular tissue, 

 containing the material destined to the nutrition of flesh. 



On considering the physical condition of flesh, it occurred to 

 me that there would be no difficulty in determining whether 

 muscular tissue is strictly a colloid mass like a jelly or not, by 

 merely immersing a piece of muscle or raw meat in water. 

 Should it be a solid colloid body, no albumen could be expected 

 to difi'use out of the meat into the water; on the other hand, if 

 it was a porous mass, and should these pores or minute channels 

 contain albumen, some of the substance would necessarily pass 

 out of the meat into the water by a process of porous distribution, 

 as would take place if a sponge containing white of egg were 

 immersed or hung up in water. 



It is an observation nearly of daily occurrence that raw meat 

 steeped in cold water yields albumen. 200 grammes of ox-flesh 

 wereminced and extracted with 125 cub. centims. of distilled water, 

 the phosphoric acid and albumen being subsequently determined 

 in the extract. On the other hand, a piece of raw beef weighing 

 200 grammes was immersed for 26 hours in 125 cub. centims. 

 of distilled water, when the phosphoric acid and albumen were 

 also determined in the fluids : the result of the analysis showed 

 that the amount of albumen which had passed out of the meat 

 in the water was less than half of that which had been obtained 

 by extraction ; while there was separated by diffusion more than 

 half the proportion of phosphoric acid contained in the extract. 

 The numerical results were as follows : — 



In 100 cub. centims. fluid 

 In 100 cub. in whicli the flesh had 

 centims. extract. been immersed. 



Phosphoric Acid . . 0-233 0-169 



Albumen . . . 2-925 1-067 



This experiment shows that flesh is permeated in every direction 

 throughout its mass with a multitude of minute channels charged 



