392 THE LIFE OF PASTEUR 



patience, soon applied to it with success the method of attenua- 

 tion by the oxygen in air. " What did we want with a new 

 disease ? ' ' said a good many people , and yet it was making a 

 step forward to clear up this preliminary confusion. Pasteur, 

 in the course of a long and minute study of the saliva of mad 

 dogs in which it was so generally admitted that the virulent 

 principle of rabies had its seat, that precautions against saliva 

 were the only ones taken at post-mortem examinations dis- 

 covered many other mistakes. If a healthy dog's saliva contains 

 many microbes, licked up by the dog in various kinds of dirt, what 

 must be the condition of the mouth of a rabid dog, springing upon 

 everything he meets, to tear it and bite it? The rabic virus is 

 therefore associated with many other micro-organisms, ready to 

 play their part and puzzle experimentalists; abscesses, morbid 

 complications of all sorts, may intervene before the develop- 

 ment of the rabic virus. Hydrophobia might evidently be 

 developed by the inoculation of saliva, but it could not be con- 

 fidently asserted that it would. Pasteur had made endless 

 efforts to inoculate rabies to rabbits solely through the saliva 

 ,of a mad dog ; as soon as a case of hydrophobia occurred in 

 Bourrel's kennels, a telegram informed the laboratory, and a 

 few rabbits were immediately taken round in a cab. 



One day, Pasteur having wished to collect a little saliva from 

 the jaws of a rabid dog, so as to obtain it directly, two of Bourrel's 

 assistants undertook to drag a mad bulldog, foaming at the 

 mouth, from its cage ; they seized it by means of a lasso, and 

 stretched it on a table. These two men, thus associated with 

 Pasteur in the same danger, with the same calm heroism, held 

 the struggling, ferocious animal down with their powerful 

 hands, whilst the scientist drew, by means of a glass tube held 

 between his lips, a few drops of the deadly saliva. 



But the same uncertainty followed the inoculation of the 

 saliva ; the incubation was so slow that weeks and months 

 often elapsed whilst the result of an experiment was being 

 anxiously awaited. Evidently the saliva was not a sure agent 

 for experiments, and if more knowledge was to be obtained, 

 some other means had to be found of obtaining it. * 



Magendie and Kenault had both tried experimenting with 

 rabic blood, but with no results, and Paul Bert had been 

 equally unsuccessful. Pasteur tried in his turn, but also in 

 vain. "We must try other experiments," he said, with bis 

 usual indefatigable perseverance. 



