446 BIOLOGY AND ITS MAKERS 



nothing more than an enumeration of tendencies with a 

 running commentary is possible. One notes first a whole- 

 some influence in the establishment of higher standards, both 

 of research and of scientific publication. Investigations as a 

 whole have become more intensive and more critical. Much 

 of the work that would have passed muster for publication 

 two decades ago is now regarded by the editors of the best 

 biological periodicals as too general and too superficial. The 

 requisites for the recognition of creditable work being higher, 

 tends to elevate the whole level of biological science. 



Improvement in Tools and Methods. This has come 

 about partly through improvement in the tools and in the 

 methods of the investigators. It can hardly be said, however, 

 that thinking and discernment have been advanced at the 

 same rate as the mechanical helps to research. In becoming 

 more intensive, the investigation of biological problems has 

 lost something in comprehensiveness. That which some of 

 the earlier investigators lacked in technique was compensated 

 for in the breadth of their preliminary training and in their 

 splendid appreciation of the relations of the facts at their 

 disposal. 



The great improvement in the mechanical adjustments 

 and in the optical powers of microscopes has made it possible 

 to see more regarding the physical structure and the activities 

 of organisms than ever before. Microtomes of the best work- 

 manship have placed in the hands of histologists the means 

 of making serial sections of remarkable thinness and regular- 

 ity. 



The great development of micro-chemical technique also 

 has had the widest influence in promoting exact researches 

 in biology. Special staining methods, as those of Golgi 

 and Bethe, by means of which the wonderful fabric of the 

 nervous system has been revealed, are illustrations. 



The separation by maceration and smear preparation of en- 



