PKOF. G. SIMS WOODHEAD^ M.A., 31. D., 



substance, antitoxin, in sufficient quantities to neutralize the 

 large doses of toxin injected in the later stages of treatment. 

 But more than this (and this is proved by the amount of anti- 

 toxin that is found circulating in the blood), not only is the 

 antitoxin formed in sufficient quantities to meet the immediate 

 demands of the organism, — i.e., to neutralize the toxin present 

 — but the process of antitoxin formation goes on long after 

 the need for its protection or neutralizing influence has ceased. 



Chemical analogies of all kinds have been put forward to 

 explain certain of the processes above described, but where 

 apart from living matter do we find this profound modification 

 of function taking place within a very short period, and con- 

 tinuing long after the exciting cause has been removed ?* 

 Here we have something that differs in almost every essential 

 feature from the most complicated chemical reactions of which 

 we have any knowledge ; and although one can imagine that 

 the chemist in his enthusiasm may be tempted in contempla- 

 tion of his greatest triumphs to say " This is a process 

 but little removed from those involved in the generation of 

 life," I know of nothing in the chemical or physico-chemical 

 realm that corresponds in nature to the marvellous process of 

 modified reaction to the special stimulation mentioned above. 

 Similar specific reactions with the production of antitoxins all 

 point to the presence of what we must still look upon as a 

 purely biological phenomenon — adaptation — a phenomenon far 

 more clearly illustrated in these specific processes than in con- 

 nection with any physiological process as ordinarily studied. 



Driesch, in liis Gifford Lectures (" The Science and Philosophy 

 of the Organism," delivered in Aberdeen in 1907), puts the 

 mattervery clearly and concisely, on page 209. Whilst admitting 

 that the considerations already mentioned afford no actual proof 

 of the autonomy of hfe, he holds that we " have gained many 

 indicia for the statement that the organism is not of the type of 

 a machine, in which every single regulation is to be regarded as 

 properly prepared and outlined." " It is precisely," he says, " in 

 the field of immunity that such a machine-like preparation of the 

 adaptive effects seems almost impossible to be imagined. How 

 indeed could there be a machine the chemical constituents of 

 which were such as to correspond adaptively to every requke- 

 ment ? to say nothing of the fact that the production of more 



* " Report on the Bacteriological Diagnosis and Antitoxic Treatment of 

 Cases admitted to the Hospitals of the Metropolitan Asylums Boai^d 

 during the years 1895-96,'" by G. Sims Woodhead. 



