municated by the diseased to a healthy animal, not to 

 all healthy animals, even of the same species. Herein 

 lies evidently our security against tuberculosis, as well as 

 against many other infectious diseases. The general 

 principle the survival of the fittest seems to have been 

 for generations at work in eradicating this disease from 

 the human family, by removing those members of it sus- 

 ceptible to tuberculosis ; the great majority of us now 

 living are as safe from tuberculosis as most dogs are from 

 anthrax. 



Another, perhaps the most profound, argument against 

 the infectiousness of tuberculosis should be considered 

 here, namely, that the fact must cause us to relapse into 

 barbarism. " Some of the most noble and tender traits of 

 humanity threaten to be undermined. The consumptive 

 who has been heretofore lavishly loved and cared for," 

 etc., " is to be isolated and shunned as a leper, if such 

 doctrines prevail " {Philadelphia Medical News, January 

 2yth, p. 94). Therefore tuberculosis is not infectious. 

 Incredible as it may appear, the author of these lines is 

 not a clergyman nor a poet, but a distinguished surgeon 

 who does not shun infectious pyaemia, septicaemia, and 

 erysipelas ; and who, we may assume, does not love his 

 child less lavishly, nor care for his patient less faithfully 

 because that child or patient may suffer from infectious 

 diphtheria or scarlatina. 



Were the susceptibility to tuberculosis as general as to 

 diphtheria, scarlatina, and measles, there might be grounds, 

 not for shunning the consumptive "as a leper," but for 

 the observance of proper precautions for the protection 

 of the healthy many, even at the inconvenience of the 

 diseased few. But since the experience of generations 

 has shown that only about one-seventh of us acquire 

 tuberculosis even with unrestrained intercourse with con- 

 sumptives, it may be questionable whether any other 

 protection than a knowledge of its infectiousness for some 

 individuals be necessary ; we do not invoke the law to 

 brand syphilitic individuals, though to this infection not 

 one-seventh but, probably, all of us are susceptible. But, 



