130 
It is also very difficult to get a clear insight into 
colloïd-chemistry. Besides the fact that many phenomena 
of it have not yet been examined systematically, there is 
another great difficulty, namely the difference of opinion 
between the colloïd-chemici in very important problems. 
It is sufficient to read something of the chemistry of 
proteins to be convinced of this. As far as the conclusions 
are concerned, Î believe not to have gone too far, however. 
It will give rise to some astonishment, perhaps, that in 
this dissertation, is not said a word of the investigations 
of R. S. Lillie (1904 etc.) The cause of this lies in the 
fact, that I thought it impossible to compare Lillie’s 
data directly with mine. 
