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SCIENCE. 



[N. S. Vol. III. No. 58. 



in great numbers in the blood of infected 

 animals, he demonstrated by experiment 

 that this bacillus rapidly loses its virulence 

 when cultivated in artificial media at a tem- 

 perature of 42° to 43° C; also that animals 

 inoculated with this ' attenuated ' virus 

 suffer a mild attack of the disease, and that 

 after their recovery they are immune 

 against future attacks, even when inocu- 

 lated with the most virulent material. This 

 discovery has been applied practically, on 

 an extensive scale, in France, Austria, 

 Switzerland and other European countries. 

 The result of anthrax inoculations made by 

 Pasteur's method in France during the past 

 twelve years was summarized by Chamber- 

 land in 1894. He reports the total number 

 of animals inoculated during this period as 

 1,788,677 sheep and 200,962 cattle ; and 

 estimates the total saving as the result of 

 the inoculations as 5,000,000 francs for 

 sheep and 2,000,000 francs for cattle. 



Another infectious disease in which Pas- 

 teur's method has been employed with suc- 

 cess is rouget, or hog erysipelas. Chamber- 

 laud states that, as a result of the protective 

 inoculations practiced with Pasteur's ' vac- 

 cines,' the mortality from this disease in 

 France has been reduced from about 20% 

 to 1.45%. Hutyra reports that during a 

 single year (1889) 48,637 pigs were inocu- 

 lated with Pasteur's vaccines in Hungary 

 with a loss of 0.29%, while the losses upon 

 the same farms in previous years averaged 

 from 10 to 30%. 



But we must pass to that portion of Pas- 

 teur's scientific work which has most en- 

 gaged the attention of the public. Pasteur 

 first announced his success in reproducing 

 hydrophobia in susceptible animals by in- 

 oculations of material obtained from the 

 central nervous system, in a communica- 

 tion made to the Academy of Sciences on 

 May 30, 1880. Continuing his investiga- 

 tions, he reported, in 1884, his success in 

 conferring immunity against hydrophobia 



in 19 dogs inoculated, in the presence of a 

 commission appointed for the purpose, as a 

 test experiment. These animals had been 

 rendered refractory by his method. The 19 

 protected animals and 19 control animals, 

 obtained from the public pound without 

 any selection, were tested at the same time. 

 The test was made upon some of the ani- 

 mals of both series by inoculation with 

 virulent material upon the surface of the 

 brain, and upon others by allowing them to 

 be bitten by rabid dogs, and upon still 

 others by intravenous inoculations. Not 

 one of the protected animals developed 

 hydrophobia; on the other hand, three of 

 the control animals out of six bitten by a 

 mad dog developed the disease, five out of 

 seven which received intravenous inocula- 

 tions died of rabies, and five which were 

 trephined and inoculated on the surface of 

 the brain died of the same disease. 



With reference to his first inoculations in 

 man, Pasteur says : 



"Making use of this method, I had 

 already made fifty dogs of various races 

 and ages immune to rabies, and had not 

 met with a single failure, when, on the 6th 

 of July, quite unexpectedly, three persons, 

 residents of Alsace, presented themselves at 

 my laboratory." 



These persons were Theodore Vone, who 

 had been bitten on the arm on July 4th; 

 Joseph Meister, aged nine, bitten on the 

 same day by the same rabid dog; and the 

 mother of Meister, who had not been bit- 

 ten. The child had been thrown down by 

 the dog and bitten upon the hand, the legs 

 and the thighs, in all in fourteen different 

 places. Pasteur commenced the treatment 

 at once, and had the satisfaction of report- 

 ing to the Academy of Sciences in March 

 of the following year (1886) that the boy 

 remained in perfect health. Since this time 

 Pasteur Institutes for the treatment of 

 hydrophobia have been established in all 

 parts of the civilized world, and the statis- 



