584 POPULAR SCIENCE' MONTHLY. 



of ninety-one; Malpighi, always in feeble health, but directing his 

 efforts with rare capacity, reaching the age of sixty-seven; while the 

 great intensity of Swammerdam stopped his scientific career at thirty- 

 six and bnrned ont his life at the age of forty-three. 



They were all original and accurate observers, but there is varia- 

 tion in the kind and quality of their intellectual product. The two 

 university-trained men showed capacity for coherent observations; they 

 were both better able to direct their efforts towards some definite end; 

 Leeuwenhoek, with the advantages of vigorous health and long work- 

 ing period, lacked the systematic training of the schools, and all his 

 life worked in discursive fashion; he left no coherent piece of work of 

 any extent like Malpighi's 'Anatome Plantarum' or Swammerdam's 

 'Anatomy and Metamorphosis of Insects.' 



Swammerdam was the most critical observer of the three, if we 

 may judge by his work in the same field as Malpighi's on the silk- 

 worm. His descriptions are models of accuracy and completeness, and 

 his anatomical work shows a higher grade of finish and completeness 

 than Malpighi's. Malpighi, it seems to me, did more in the sum total 

 than either of the others to advance the sciences of anatomy and 

 physiology and through them the interests of mankind. Leeuwenhoek 

 had larger opportunity; he devoted himself to microscopic observation's, 

 but he wandered over the whole field. While his observations lose all 

 monographic character, nevertheless they were important in opening- 

 new fields and advancing the sciences of anatomy, physiology, botany 

 and zoology. 



The combined force of their labors marks an epoch in the estab- 

 lishment of the scientific method and in the ushering in of a new grade 

 of intellectual life. 



