288 THE PRESENT EVOLUTION OF MAN — PHYSICAL 



do often perish of tlieir first attack ; as, for instance, of 

 tubercular meninoitis, or of acute phthisis (galloping 

 cousuuiption) ; but the very general prevalence of more 

 resistant individuals, who as regards their powers of 

 defence against the bacilli correspond to a far later stage 

 in the phylogeny, justifies Laennec's dictum. 



" In a very large number of cases also, Laennec's 

 first proposition is true, and we may extend it by saying, 

 that not only do they not die of the first attack, but not 

 a few recover from it a,nd have no more seizures. Un- 

 fortunately this occurrence is not so common among the 

 patients of our consumptive hospitals as it is among the 

 rich or amongst those who can take the necessary pre- 

 cautions against further attacks." ^ 



"O" 



It is clear, then, that the men of our race are very 

 generally so resistant to tuberculosis, that even after 

 infection their phagocytes, under slightly improved 

 conditions, are able to wage successful war against the 

 microbes. It is clear also that no immunity can be 

 acquired against the disease, since those who ai'e 

 recovered, under fit conditions, take it a^fain and 

 again. Tlieir only safety lies in the absence of the 

 pathogenic micro-organisms. On this account I have 

 always thought it unwise, in the interests of the 

 patients, to gather them into special hospitals. How- 

 ever excellent the arrangements may be in such 

 establishments, they can hardly be made so perfect 

 as to exclude the possibility of those who have recovered, 

 in so far that their phagocytes have destroyed the micro- 

 organisms within them, receiving fresh infection from 

 inmates who are yet diseased. Doubtless such establish- 

 ments discharge many persons cured of their complaint, 

 but these fortunate cases, I apprehend, are usually those 



1 Dr. Arthur Ransom, Britisli. Medical Journal, July 23, 1892. 



