president's address. 219 



experiments we have come any nearer to the making of actual 

 protoplasm. 



The imitation of streamings and amoeboid changes and rapid 

 movements of position are all physically explicable, and no 

 matter hoAv apparently complex the thickened portions of the 

 united froth bubbles may apj)ear, they are, by sufficient magni- 

 fication, resolvable into minuter bubbles. But he must have 

 lenses such as I have never yet been able to touch, or must 

 have a secret in the use of them which I do not know, who can 

 resolve the strange, the at present undefinable, reticulation, 

 radiate, or plexus-like structure of protoplasm into bubbles. 



I have examiued all the movements of these artificial foams 

 with care and patience, and after years of observation on pro- 

 toplasmic movement, I find that they differ much and in many 

 ways from the movements seen in living matter. The co- 

 existence of streams in opposite directions is not uncommon in 

 living cells ; every observer, indeed, will have noted an occa- 

 sional sudden reversal of cellular streams, and not unusually 

 the cessation of the stream and its subsequent recommence- 

 ment. But more than this, the stimulating action of oxygen 

 or electric energy is at once manifest on the living matter, but 

 they are practically inert on foams. 



That approximate physical explanations of certain initial 

 movements of living matter, as in white corpuscles, pus- 

 corpuscles, amoebee, and so forth may have been discovered by 

 ingenuity and effort, by no means proves that the same results 

 are brought about in the same way in living protoplasm, nor 

 do they prove that we are, as yet, any nearer the discovery of 

 the ultimate structure of protoplasm itself. 



We are grateful for the light given and the amount of truth 

 disclosed, but a streaming froth and streaming living proto- 

 plasm are immeasurably far apart. 



When the higher complex chemical nature of protoplasm is 

 considered, side by side with the totally different conditions 

 under which a compound, capable also of being made in the 

 laboratory, is made by living matter, we have surely a strong 

 reason for considering that vital chemistry is at least unique, 

 and that it will not inevitably follow that because delicately 

 made and carefully observed foams simulate the internal and 

 external movements of protoplasm in its simplest form, that, 

 therefore, the phenomena of life are the less difficult to explain. 



