ASPECTS OF ADSORPTION PHENOMENA 



179 



002. 



also that if we attempt to wash out the dye by means of 10 per cent, 

 alcohol it will require, theoretically, an infinite number of changes 

 of the solvent to effect complete removal of 'the dye. I found, in 

 fact, that if the piece of paper which was stained deep-red in the 

 O'OO2 per cent, solution was allowed to soak in 10 per cent, alcohol, 

 a trace of dye only was removed each time a fresh supply of alcohol 

 was added ; the alcohol became very faintly pink, the colour only to 

 be detected in a deep layer, while the paper did not perceptibly lose in 

 depth of colour after several extractions. 



II. WASHING-OUT OF ELECTROLYTES 



It will be seen, on a little consideration, that the great difficulty 

 of removing the last small part of the ash-constituents of proteins 

 may be readily explained on the hypothesis that the case is one of 

 adsorption. The hyperbolic form of the characteristic curve' shows 



