ORGANIC REGULATION 105 



such instances, their presence and formation is organic- 

 ally determined by something beyond; and of this 

 something we can form no physical or chemical pic- 

 ture. We also realise more clearly that in following 

 the physical and chemical picture of the oxygen from 

 the outset we have only done so by ignoring the organic 

 control which, though present, seems less intimate. 

 We have ignored, or put aside for the time, the regu- 

 lated maintenance of breathing, the maintenance of 

 the delicate normal structure of the lungs and of other 

 parts connected with breathing, the regulation of the 

 circulation and of the composition of the blood, and 

 the maintenance of endless other things in which 

 organic regulation manifests itself. But when we 

 reach the living tissues we can ignore the organic regu- 

 lation no longer : for we can see nothing clearly except 

 an evident manifestation of the most intimate organic 

 regulation. The physical and chemical picture is 

 entirely obliterated by the picture of organism. 



We may reflect that although we cannot at present 

 trace the combinations into which oxygen enters in the 

 living tissues, yet the oxygen atoms are there in some 

 form. We can demonstrate their presence by ele- 

 mentary analysis, and we can separate chemical com- 

 pounds, such as proteins, which contain oxygen. It 

 can therefore be only a matter of further investigation 

 to discover how the oxygen and other atoms combine 

 in the living tissues and how these compounds react 

 with one another to bring about the phenomena of life. 

 This reflection brings us very close to a fundamental 

 question. Physics and chemistry have brought us not 



