218 



ENDOSMOSE, 





FIG. 153 (i real size). 



but in a very short time the pressure of the liquid upon 

 the bladder causes the latter to bulge out, the capacity of 

 the bottle is thereby increased, and 

 the liquid in the glass-tube recedes 

 again into the bottle. Very soon tl 

 extension of the bladder by pressur< 

 and the consequent descent of tl 

 liquid in the tube, reach a limit 

 the liquid is now seen to rise slowb 

 in the tube, because the water in 

 outer vessel passes more rapidb 

 through the bladder to the solutic 

 of sugar, than the latter passes froi 

 the inner vessel to the water. In 

 the course of a few hours the liquid 

 rises several centimetres, and if a narrower tube be used, 

 the liquid will clearly rise still higher. 



Water and white of egg manifest strong endos- 

 niose. The pellicle which lines the shell and sur- 

 rounds the liquid contents of the egg, may be used 

 with advantage for exhibiting the phenomenon. About 

 40 CC of crude concentrated hydrochloric acid are mixed 

 with about 200 CC of water in a capacious vessel, capable 

 of containing about a litre. When a hen's egg (one 

 with a thin shell being selected) is placed in the liquid, 

 the shell is dissolved with strong effervescence ; after 

 about half an hour, the liquid having been frequently 

 but very cautiously stirred with a splinter of wood, 

 the whole of the hard shell is removed. The whole 

 of the liquid and froth are now carefully poured off; 

 the egg, which has become pellucid and quite soft, is 

 repeatedly washed with clean water, and the vessel also 



