Manchester Memoirs, Vol. xliii. (1899), No. \%. 13 



to me to justify the publication of my own speculation. On 

 this point I may perhaps usefully quote the remarks of an 

 esteemed correspondent, who is also a distinguished specialist. 

 " Your view of the etiology of cancer," he writes, " is in some 

 respects parallel to that of Cohnheim, though it differs in this, 

 that whereas he regarded the cancer cells as cells which had 

 retained the undifferentiated embryonic characters, you (as I read 

 it) regard them as having re-acquired those characters by the 

 action of detrimental agencies acting upon them from within or 

 without. This, as you say, does not exclude the possible action 

 of parasites as the cause of the degeneration ; your bias is, 

 however, obviously towards the side of a physical causation, more 

 especially deficiency of oxygenization." 



With reference to my remarks on disturbed or interrupted 

 irrigation, my attention has also been called to the evidence of 

 an abundant supply of blood to the affected parts, which is 

 indicated, for instance, by the number of arteries requiring 

 ligature after an operation. On this point I wish to say that the 

 pathological descriptions of this phenomenon which I have read 

 suggest congestion rather than healthy circulation ; in external 

 nature we have sluggish water courses which tend to the forma- 

 tion of a miasmatic area. An excessive blood-supply, moreover, 

 seems mechanically and chemically inconsistent with complete 

 oxygenization. 



Finally my appreciative and friendly critic points out that 

 cancer appears in (apparently) very robust persons ; that there is 

 a form of cancer which occurs almost exclusively on the area of 

 the body most richly supplied with blood, the face ; and that it 

 has been noticed that almost the only victims to this form in 

 Hamburg are sailors, who of all people may be supposed to be 

 most abundantly supplied with free oxygen. I wish it to be 

 understood that I refer to oxygen in the paper rather as an 

 illustrative speculation than as a suggestion on which depends 

 absolutely the general argument of the paper, that of a biological 

 change due to alteration of environment — say nutrition or nerve 

 stimulus. But in regard to a disease which is admittedly involved 

 in mystery, it is useful to have a definite working hypothesis. 

 If the oxygenization idea is adopted as such an hypothesis, then 

 the case of the Hamburg sailors will present itself as an exception 



