THE LIVING SUBSTANCE. 



113 



mass, invisible except when in a contracted state, yet wide 

 enough for a double set of substance currents to flow upon 

 each other, and possibly with even a third supporting area 

 between them, such as obtains in many filose extensions of 

 protoplasm; wide enough it certainly proves itself to contain 

 the substance and much structure, and room enough for such 

 structural organizations and changes as are associated with 

 intermittent organized contraction. From the outer surface of 

 the cup were sent off at times delicate filose processes whose 

 mass being great compared with that of the film looked quite 

 large. These haVfe been taken by some observers to be ad- 

 herent bacteria. 



[103] In Gromia the contraction phenomena of threads and 

 webs are even more marvellous. Such facts, with others pre- 

 viously cited for filose activities, go far to convince one that to 

 limit protoplasm and protoplasmic phenomena and protoplasmic 

 physiological structure to those grosser masses we now discern 

 would be to stultify ourselves and to lose many chances for 

 valuable effort. If Biology is to be the guide of physiological, 

 medical, and hygienic science, which would seem to be her 

 highest function, it is such minutiae of life history and possi- 

 bilities of the living substance, which offer best fruit to that 

 willing patience, that single-hearted, loving receptiveness of 

 research for which human progress ever waits and upon which 

 it still must lean. 



One cannot but wonder with a child-like wonder, at the 

 infinite smallness possible to the living substance as such, and 

 even as organism, but to refuse credence because of this unimagi- 

 nableness would be as childish as for one who had never looked 

 through a microscope to disbelieve in the Protozoa altogether; 

 as childish as to refuse to believe in those hosts of mighty 

 stars which for the naked eye have no being. 



The nature of a physical foam such as postulated here, makes 

 possible for protoplasm a disposition of its elements in such 

 minute sub-divisions as water has in air; makes it possible for 

 the substance as such when seen from afar, — as with our poor 

 optical powers we still must see it, — to look as still and struc- 

 tureless as those cloud masses which seem to hang motionless 



