MECHANISM OF ABSORPTION. 57 



drained of the stagnant fluid in less than two minutes 

 after the stream was turned through the pipe. 



I may refer to the same page for a proof of the 

 statement that this imbibing power of the stream is 

 proportioned to its velocity. 



I will mention one other proof. While a cistern 

 is full the rate of discharge and consequent velocity 

 of the stream through the orifice at its bottom will, 

 of course, be greatest. Now, if the apparatus above 

 described be fitted into a pipe connected with this 

 orifice, it will be found that the stagnant fluid will 

 rapidly rise to a certain height in the glass tube ; 

 but as the depth of the column of water in the cis- 

 tern diminishes, the fluid in the tube will oscillate 

 and fall till the stream becomes so tardy as not to 

 exert any marked influence on the stagnant fluid. 



Having now proved the existence of this power, 

 and also that it is proportioned to the velocity of the 

 stream, the first step towards the application of this 

 principle to the explanation of the process of ab- 

 sorption in the living body, is to show that the same 

 force, whatever it may be, will act through one or 

 more membranes. 



Accordingly, the short end of the glass tube being 

 covered with membrane and its long end immersed 

 in a coloured fluid, I found that within five minutes 

 after the stream had commenced to flow, the whole 

 of the air present in the tube (which was twelve 

 inches long and its bore one-fourteenth of an inch 

 wide) had been absorbed and its place supplied by 

 the coloured fluid. A continued slow ascent of 

 the latter was still proceeding when I was compelled 



