KLUYVER AS SEEN BY HIS PUPILS 



Kluyver saw to it that this signified the start of a greatly intensified 

 education. 



The first duty of the new assistant was usually the preparation of 

 the demonstration material for the lecture courses. He could lean on 

 an old, hand-written manual, compiled and amended by successive 

 generations of assistants, for planning the execution of the experiments 

 which were required for a particular lecture and which had been out- 

 lined during the special weekly conferences with the professor. Never- 

 theless, the task made heavy demands on the time and capacities of 

 the young assistant. Every week new experiments were needed and 

 even though, aided by the information contained in the manual, he 

 managed to get them started with a minimum of delay, some of them 

 were not immediately successful. The limited time available, with the 

 deadline determined by the time of the lecture, did not always permit 

 of repetitions, so that at the critical moment the demonstration mate- 

 rial might expose more or less serious gaps, a permanent source of 

 worry for the assistant. It was Kluyver's custom to inspect the results 

 just before the lecture, accompanied by the anxious assistant; he nev- 

 er complained about the bad experiments but singled out for praise 

 those that had come out well; and he could make the assistant feel 

 that the whole success of the lecture actually depended on the latter's 

 contribution. One may, of course, question the efficacy of demonstra- 

 tions as far as the education of an audience is concerned, and Kluyver 

 himself certainly did not overestimate it. His main reason for perpet- 

 uating the practice was its immense value in terms of the education 

 of the assistant who had a unique opportunity to become familiar with 

 a wide variety of organisms and broaden his practical experience un- 

 der expert guidance. Another important reason was that these exper- 

 iments led to the accumulation of valuable information, covering a 

 wide range of subjects; occasionally they cast doubt on current views, 

 and then yielded problems for more detailed studies afterwards. 



In addition to the above task the assistant usually conducted experi- 

 ments on a subject of his own choosing, which had been agreed upon 

 during extensive deliberations in which both the assistant and the pro- 

 fessor voiced their ideas. It is not surprising that the great freedom 

 Kluyver allowed his students implied that often a great diversity of 

 problems was being simultaneously investigated in his laboratory. Al- 

 though this widened the horizon, it may have impeded the rapid de- 



55 



