28 BACTERIOLOGY 



announced the constant presence in the blood of animals 

 dead of anthrax of rod-shaped bodies, and in 1863 Davaine 

 showed the blood of such animals to be infective for normal 

 animals. This distinct step in advance so attracted the 

 attention of Pasteur that he soon became closely identified 

 not only with studies of this particular disease but with 

 other diseases of domestic animals and fowls. Pasteur was 

 already known in the fields of physical and natural sciences 

 through his basic work on the organic isomers and his dis- 

 coveries in the field of fermentation. His conception of 

 fermentation as a function of living cells was so opposed to 

 the views generally held at the time, and especially those 

 held by von Liebig perhaps the most distinguished chem- 

 ist of his day that endless discussion, amounting at times 

 almost to polemic, took place. Pasteur's opinions finally 

 triumphed. His manifold investigations at this time were 

 so novel, so progressive; his interests so versatile and so in 

 accord with the new thought that was beginning to develop, 

 that he was soon regarded as the most suggestive and impres- 

 sive contributor of his time. His subsequent studies upon 

 vaccination with living attenuated viruses were of such 

 fundamental nature both scientifically and practically as 

 to justify the opinion that the science of immunology began 

 with his observations and investigations. The circumstances 

 surrounding his public demonstration that sheep can be 

 protected from anthrax infection by the process of vaccina- 

 tion with a living, attenuated virus constitutes one of the 

 most dramatic incidents in the history of applied science. 



The catholicity of Pasteur's interests in all matters con- 

 cerning the world of living, microscopic things, the benefits 

 that accrued from the application of his keen analytic men- 

 tality to the solution of problems of domestic, agricultural 



