OUTSTANDING BIOLOGICAL ADVANCES 15 



tion should establish that it is universal in all or- 

 ganisms before the general conclusion could be 

 reached. 



Let us now estimate the consequences of the dis- 

 covery of protoplasm. Here for analysis we have 

 disclosed the living substance of all animals and 

 plants. In this physical substratum all vital ac- 

 tivities exhibit their manifestations. Now for the 

 first time was recognized the basis of physiological 

 activities. If the naturalist is ever to bring vital 

 activities under close analysis, he must do so by 

 becoming acquainted with the properties and the 

 behavior of protoplasm. Even in its simplest form 

 it exhibits the germ of all properties that appear 

 better developed in higher organisms. 



The recognition of the nature of protoplasm, to- 

 gether with the adoption of the cell-theory, led to the 

 foundation of modern biology, and the progress of 

 biology, since 1861, has been largely a matter of 

 becoming better acquainted with protoplasm. By 

 means of these discoveries vital phenomena were seen 

 in a new light and progress was started. 



It is to be remembered throughout this book that a 

 great scientific discovery is never the product of one 

 man, nor of two men. Although in bringing forward 



