56 ENDOSMOSE LECT. III. 



the endosmometer in which the external surface of the skin 

 is turned towards the solution of sugar, the elevation is 30 

 millimetres, while in the other instrument it is only 20 

 millimetres. With an albuminous solution and gum water, 

 the differences observed from the commencement of the 

 experiment are the same as those which usually take place ; 

 and, although we ultimately find the albuminous solution 

 rises 8 millimetres, and the solution of gum rises 20 milli- 

 metres, when the external surface of the skin is turned 

 towards the liquid ; we observe, on the contrary, that when 

 the position of the skin is reversed, the albuminous solution 

 rises only 4 millimetres, and the solution of gum 17 milli- 

 metres. 



The fresh condition seems more necessary for the skin of 

 the eel, than for that of the frog and torpedo, when we wish 

 to mark the difference in the elevation of the liquids con- 

 tained in the endosmometers. If the skin of the eel has 

 been removed from the animal for one or two days, no dif- 

 ference is observed between the two positions of the mem- 

 brane; and the solutions of sugar, albumen, and gum 

 respectively rise, in the same space of time, to an equal 

 extent in both instruments. 



Endosmose between Alcohol and Water. By employing 

 water and alcohol, Dutrochet obtained the current in the 

 direction from the former to the latter. This consequently 

 formed an exception to all the other cases, in which he found 

 that the direction of the current was from the least to the 

 most dense liquid. 



-The influence of the position of the skin, employed as 

 the membrane interposed between these two liquids, has 

 been rendered evident by our experiments ; but the position 

 favourable to the current, which is constantly from the water 

 towards the alcohol, is not the same for the three kinds of 

 skins alluded to. Thus, when we use the skin of the frog, 



