ESSAYS ON BACTERIOLOGY. 145 



careful physical examination slioiiM have been made. 

 Evidence of cerebral or renal tuberculosis sbaiild ex- 

 clude this method of diagnosis, and in all cases violent 

 reactions are unnecessary and should be avoided. 

 With these precautions the tuberculin injection prom- 

 ises to become a valuable aid in the definite recogni- 

 tion of the disease in those early or obscure cases in 

 which the other means of diagnosis are not available. 

 The immediate future will doubtless bring the solu- 

 tion of some questions as yet unsettled concerning 

 this method. If it shall be settled that the tuberculin 

 reaction, properly induced, is a specific one, and lim- 

 ited to tuberculosis, and that the supposed dangers 

 may, by its skillful use, be practically eliminated, we 

 shall indeed be in a position to reaffirm the statement 

 heretofore ventured: that the diagnostic problem of 

 tuberculosis has been solved, and another contribution 

 made by bacteriology to practical medicine. 



