12 MANUAL OF BACTERIOLOGY. 



washing the hands of the attendant at child-birth in solutions 

 of chlorine or chloride of lime in addition to cleansing them 

 with soap and water. 



During the same period similar ideas were advanced by Dr. 

 Oliver Wendell Holmes in the United States. His paper on 

 "The Contagiousness of Puerperal Fever" appeaed in 1843. 

 A lively controversy lasting several years was provoked, in 

 which Holmes defended his position with great vigor. His 

 admirable literary style served him effectively.* 



In the first half of the nineteenth century, with improved 

 microscopes, knowledge of minute living things grew rapidly, 

 chiefly with respect to infusoria and other relatively large 

 forms. In 1840 Henle described the part played by micro- 

 organisms in producing disease in terms surprisingly in accord 

 with views held at the present time. His deductions were 

 based almost entirely on knowledge of the general -nature, 

 spread and course of infections. So, too, Villemin anticipated 

 the discovery of the bacillus of tuberculosis, for he transmitted 

 the disease to animals, by inoculating them with material from 

 cases of tuberculosis in man. 



The key to exact knowledge of the microorganisms of disease 

 was finally discovered in the study of fermentation. No 

 better illustration could be found of the possible value to 

 mankind which may lie in any addition whatever to the com- 

 mon stock of knowledge. The study of bottles of bad-smelling 

 broth would have seemed, fifty years ago, a most unpromising 

 beginning for the discovery of the causes of cholera, plague 

 and the like, or for an antitoxin for diphtheria. 



Studies on Fermentation and Spontaneous Generation. Two 

 observers (Schwann, Cagniard-Latour, 1837) almost simul- 

 taneously advanced the idea that yeast-cells were living organ- 

 isms, and that the fermentation of solutions of sugar was due 

 to their growth. This amused a controversy which lasted more 



* See O. W. Holmes. Medical Essays. Houghton, Mifflin & Co., 1889. 



