1 6 THE POPULAR SCIENCE MONTHLY 



to bacteriology the technique necessary for its rapid development. 

 Koch was called to the Imperial Board of Health in Berlin in 1880, 

 and started the first laboratory founded for the study of bacteriology 

 and public health problems. In this laboratory, methods of studying 

 and photographing bacteria were developed, methods of disinfection 

 based on the knowledge of spore resistance were elaborated, and the 

 study of the bacteriology of individual diseases inaugurated. As a result 

 of the latter activity, he announced, in 1882, the discovery of the 

 bacillus of tuberculosis, and it is not too much to say that his announce- 

 ment astounded and profoundly stirred the entire civilized world. In 

 the same year Loffler and Shiitz announced the discovery of the bacillus 

 of glanders, and Pasteur published an account of the bacteriology of 

 swine erysipelas; this was the beginning of an active period with dis- 

 covery crowding on discovery. In 1883 came Koch's announcement of 

 the comma bacillus as the cause of cholera; in 1884 Loffler's description 

 of the bacillus of diphtheria and Nicolaier's discovery of the bacillus of 

 tetanus. So the march of discovery continued until the roll of dis- 

 eases of known etiology in a short time included typhoid fever, pneu- 

 monia, meningitis, influenza, bubonic plague and the various surgical 

 suppurations. 



The rapid discoveries of disease-producing microorganisms estab- 

 lished definitely Pasteur's doctrine of specificity as applied to etiology 

 and led at once to an interest in public health measures which increased 

 ds the years passed, until now it has become one of the most vital inter- 

 ests of our social system. Even in the early eighties, with a knowledge of 

 the etiology and mode of transmission of a few diseases and of Lister's 

 results in antiseptic surgery, it was possible to postulate general pro- 

 phylactic measures safeguarding the individual and the community, and 

 as knowledge of etiology and transmission increased, so did prophylaxis. 

 Hygeia was again enthroned and it was recognized that " an ounce of 

 prevention is worth a pound of cure." 



But prophylaxis was not entirely satisfying. If a specific etiology, 

 why not a specific therapy for bacterial diseases ? Men remembered inoc- 

 ulation for smallpox introduced into England by Lady Mary Wortley 

 Montagu early in the eighteenth century. This procedure, the inocu- 

 lation of healthy individuals with material from the pustules of those 

 ill with a mild form of smallpox had materially reduced the fatality of 

 the disease. The procedure, it is true, had been made illegal in Eng- 

 land in 1840, because of the greater success and less danger of Jenner's 

 wonderful discovery (1798) of vaccination with the fluid of the pustule 

 of cowpox. Inoculation, however, despite the fact that it sometimes 

 caused severe and fatal cases of smallpox and perpetuated foci for the 

 dissemination of the disease, had demonstrated that the mild inocula- 

 tion disease visually protected against the more severe forms. That 



