CRUISES OF THE "MICHAEL SARS " 



105 



In addition to the silk nets Gran now commenced using 

 his big steam centrifuge (Fig. 91) for centrifuging the water 



Fig. gi. — The Large Centrifu 



samples from difterent depths. Several successful experiments useofthe 



had already been made centrifuge. 

 with it, but it was at this 

 station that he started to 

 employ it systematically, 

 and he continued to avail 

 liimself of its help until 

 the end of the cruise. By 

 means of it he was able 

 to collect in a little drop 

 below the microscope all 

 the most minute organ- 

 isms, and in spite of the 

 movements of the little 

 ship and the vibration 

 from the propeller, he 

 was able with his micro- 

 scope to study the many 

 hitherto unknown forms 

 in their living state, to 

 draw them, and to count the number of the different species 

 (Fig. 92). A full description of these investigations will be 



Fig. 92. 



-Gran counting the smallest 

 Microscopic Plants. 



