1890.] NEW-YORK MICROSCOPICAL SOCIETY. 39 



though infinitely extended and interwoven through the whole 

 organism. Upon this warp the ancient figure of a vital spirit 

 may easily be rewrought ; once more the way is prepared for a 

 re-entrance of the spiritualistic conception of life. The breath 

 of speculation has thus blown upon the surface of truth, and we 

 have seen wave after wave roll by, each in its turn filling the 

 field of vision and obscuring the level horizon beyond. But one 

 wave cannot be more permanent than another, and the last we 

 have looked upon is not in fact the last. 



While the protoplasm theory has been assuming the form just 

 mentioned, the cell doctrine also has been taking on an entirely 

 new aspect. The door has suddenly been opened to a whole 

 world of hitherto unknown non-nucleated organisms whose study 

 is now engrossing the attention and monopolizing the energies 

 of investigators everywhere. Bacteriology is the key to present 

 biology. Strangely enough, too, we are once more eagerly 

 searching for a solution of the problem of life through a close 

 scrutiny of the phenomena of death ; for these new organisms, 

 which are found to swarm in unimaginable plenitude, seem to 

 be the counterbalance on the forces of vitality. " Mildew, 

 mould, bacteria, * * * * monads, two thousand of which 

 would go to make up a millimeter, all these microscopic 

 organisms are charged with the great work of re-establishing 

 the equilibrium of life by giving back to it all that it has 

 formed." " 



To Louis Pasteur belongs the credit for a large part of the 

 labor of investigating the offices and actions of these micro- 

 organisms, or microbes, in the processes of disorganization and 

 dissoUrtion. To him belongs the whole of the credit for reduc- 

 ing these processes to a' single genus or type. He first explained 

 to us the modus operandi of the formerly mysterious operations 

 of death, decay and putrefaction, with their accompanying and 

 complementary phenomena of resuscitation, nutrition, and repro- 

 duction. As M. Radot says, in summing up Professor Pasteur's 

 conclusions on this subject, " All that has lived must die, and 

 all that is dead 'must be disintegrated, dissolved or gasified ; the 

 elements which are the substratum of life must enter into new 

 cycles of life. If things were otherwise the matter of organized 

 beings would encumber the surface of the earth, and the law of 



" " Louis Pasteur, His Life and Labors." By his Son-in-law (M. Radot). 



