JACOBUS HENRICUS VAN'T HOFF. xi 



A few words in conclusion in reference to \"an't Hoff the man. 

 The writer was fortunate enough to have worked in the laboratory 

 of Van't Hoff in Amsterdam in the spring of 1894. His method of 

 work was somewhat as follows : When interested in a problem he 

 would gather together all the data bearing upon it, assign what he 

 considered the proper value to each determination and then as the 

 result of such comparisons draw his conclusions. 



There has been a wide diversity of opinion as to whether \^an't 

 Hofif was, or was not, a great experimenter. While this is a matter 

 of very little consequence, because there are many to experiment for 

 every A'an't Hoff to generalize, this difference in opinion arose I 

 think as follows : A'an't Hoff published very few experimental results 

 until he took up the problem of the conditions under which the salt 

 beds were deposited. This naturally led to the conclusion that he 

 had done very little experimental work, while such was not the case. 

 He published very little experimental work not because he did very 

 little, but because of his attitude towards such w^ork. He did not 

 publish results simply for their own sake. If they confirmed or 

 disproved some theory or generalization in which he was interested, 

 they were published, otherwise not. He looked upon experimental 

 results as valuable not in themselves, but just as they bore upon 

 some generalization. During my student days in his laboratory 

 Van't Hoff" was working very intently and for long hours, but not 

 a result that he obtained during that period was ever published. 

 Personally, I regard Van't Hoff' as a very skillful experimenter, but 

 he looked upon experimental results in a dift'erent way from most 

 men. 



During the time at least that I was with \*an't Hoff' in Amster- 

 dam, he impressed me as living under an intense strain. His every 

 motion suggested one keyed to a high pitch. He had wonderful 

 power of concentration, which reminded one of Rowland. In Berlin 

 he seemed to have " let down " as we usually say. He \yas living 

 on a much lower key, probably due in part to the disease which 

 much too early ended his career. 



When I saw him for the last time last summer a year in Berlin, 

 it was obvious that he was losing in the fight against the disease. 



