138 SCIENCE PROGRESS 



augurated the methods of malaria reduction which were subsequently carried 

 out properly by the Americans at Havana and Panama, and by Malcolm 

 Watson in the Federated Malay States — perhaps the greatest advance in 

 tropical sanitation ever made. 



Manson was a parasitologist and a doctor, not a sanitarian. I do not 

 think that he ever attempted to apply his filaria-mosquito work for the 

 practical reduction of filariasis. When I commenced mosquito reduction 

 in Sierra Leone in 1901 he, like many other doctors and biologists, was 

 astonished and even alarmed, and, contrary to statements which have been 

 made, did not in any wa^'- originate or assist that advance. When I was 

 begging for practical measures in Sierra Leone in 1900 he spent money on 

 keeping two or three gentlemen in a mosquito-proof house in the Campagna 

 for a few months in order to provide an additional proof of the mosquito- 

 theory of malaria — which had been already proved ! ^ How far he was re- 

 sponsible for the failure of the Colonial Of&ce and other British Government 

 departments as regards malaria-prevention (see Science Progress No. 56, 

 p. 664, April 1920), I cannot say ; but neither Sir William MacGregor nor I 

 could get a hearing there on that matter. I think, however, that Manson's 

 duties concerned only medical cases. 



He suffered much from claqueurs, who in puf&ng him and incidentally 

 themselves and their institution caused considerable offence among those 

 who knew the facts ; and there was a disagreeable affair at the Royal Society 

 in consequence, in 1905. I see that the same gentlemen are still repeating 

 the same absurdities in the numerous obituaries which have appeared — 

 not one of which, even in the medical or scientific press, has been quite 

 accurate. It is shameful that obituary notices should be exploited in this 

 manner, and I am glad to see that Sir Ray Lankester called attention to 

 the point in Nature for April 29, 1922. It is not true, as stated in the Lancet, 

 April 15, 1922, that Manson " was the first to trace the connection between 

 the mosquito and the malaria parasite " : and Colonel W. G. King has already 

 pointed out [Nature, May 20, 1922) that " the work of Ross proved Manson's 

 theories in essential details incorrect and misleading." An exact statement 

 of the facts will be found in my Prevention of Malaria. 



Most of Manson's guesses, such as those regarding sleeping sickness and 

 yellow fever, were not as fortunate as his induction regarding malaria. Genuine 

 science rightly refuses to allot much or any credit to arm-chair speculations 

 by those who do not undertake the labour and expense of testing them, but 

 afterwards try to claim discoveries on the strength of them. Manson himself 

 did not make this mistake, but modern " medical science " is full of poseurs 

 who do — see, for instance, the absurd letter by L. W. Sambon in Nature, 

 May 27, 1922. 



But in spite of his friends Manson was a great man. A grave and im- 

 pressive teacher, he exerted profound influence over young men, and his 

 literary style was so excellent that his published papers and books are not 

 only full of facts and ideas, but are as interesting as any histories can be. 

 These are common virtues ; but his parasitological studies lifted him above 

 the sphere of the doctor and the teacher into that of the discoverer. In 

 my opinion he was never adequately treated by his countrymen. Long 

 before he retired he ought to have been placed by them in a position of 

 independence in which he could have devoted the remainder of his life to 

 the investigations which he loved. 



Ronald Ross. 



1 He consulted me on this matter beforehand. I told him that it would 

 provide no proof at all. He admitted this, but said that it would be a good 

 advertisement of the theory. It is now impudently vaunted even in the 

 medical press as the final proof of the theory ! No one can accept this who 

 knows anything about either malaria or the nature of scientific proof. 



