PATHOGENIC BACTERIA. 361 



Pasteur-Chamberland bougie of unglazed porcelain. It there- 

 fore represents the products of tubercle bacilli. It was pro- 

 posed by Koch as a remedy for tuberculosis, but it has not 

 met with great success, and is little used as a therapeutic 

 agent. It has been found, however, of great value in the 

 diagnosis of tuberculosis, especially in cattle. When tuberculin 

 is injected into a tuberculous animal there results considerable 

 general disturbance, of which the mo'st noticeable evidence 

 is a sudden rise in temperature, while hyperemia is excited 

 around the tuberculous area. In a healthy subject the in- 

 jection produces no reaction; but there is, nevertheless, danger 

 attending its use. To avoid the objections to the injection of 

 tuberculin in human beings, Calmette* and Wolfe-Eisner 

 independently recommended the application of tuberculin to 

 the conjunctiva as a means of diagnosis. A marked hyper- 

 aemia of the conjunctiva follows this procedure in tuberculous 

 individuals, while this is very slight or entirely absent in 

 healthy persons. In tuberculous patients aside from some 

 discomfort and interference with vision there is no serious 

 consequence as a rule, though in some cases there is, however, 

 considerable oedema and even purulent exudation. As a 

 diagnostic measure in cattlef it has been found accurate in 

 the great majority of cases. Concerning tuberculosis in cows, 

 see page 151. Supposing that some curative principle exists 

 in the bodies of the tubercle bacilli themselves which could 

 not be procured from cultures deprived of their bacilli by 

 nitration through porcelain, Koch has recently proposed a new 

 form of tuberculin called "tuberculin R," which consists of an 

 extract made from dried and pulverized living tubercle bacilli. 

 The value of this new tuberculin as a remedy is at least doubt- 

 ful, and physicians are disposed to regard it as dangerous. 



*Calmette. Comptes rendus de 1' Academic des Sciences. June 17, 1907. 

 fFor details as to its use in cattle see V. A. Moore. Infectious Diseases of 

 Animals. 1906. p. 196. 



