244 EXPE?JMENTAL INVESTIGATION OF THE ACTION OF MEDICINES. 



apparent change in tlie animal's body to account for it. The 

 most active of these substances are chlorine, bromine, corrosive 

 sublimate, iodine, permanganate of potash, and creasote. After 

 these comes quinine, less powerful than they, but far more so 

 than other organic alkaloids. Even strychnia, so fatal to liigher 

 animals, lias barely one-fourth the power over these lower 

 organisms which is possessed by quinine, a substance which is 

 dangerous to mammals only in such large doses that we are 

 accustomed to look upon it as a remedy, but hardly at all as a 

 poison. 



Action on Vihrioncs and Bacteria. — If a piece of boiled meat 

 or white of Q<^g be allow^ed to lie in water for a few days, or a 

 little of Pasteur's solution be exposed in a glass, trie fluid 

 becomes milky, and vibriones and bacteria are formed in large 

 numbers. Pasteur's solution is made by dissolving 10 grams of 

 sugar, 5 decigrams of tartrate of ammonia, and 1 decigram of 

 yeast-ash, in 100 c.c. of water ; or a little white of egg may be 

 added to the hay infusion, when the Infusoria soon disappear, 

 and" it remains full of bacteria and vibriones. A drop may 

 now be taken, diluted with another drop of water, and the 

 action of drugs on vibriones examined in the same way as on 

 Infusoria. 



In this way it is found that the same substances which kill 

 Infusoria also prove destructive to vibriones and bacteria : and 

 if they kill these organisms when outside the animal body, they 

 should do so likewise when they are inside, and thus cure 

 diseases that may be caused by their presence. Now, bacteria 

 have been said to be the cause of malignant pustule, and they 

 are at all events frequently present in large numbers in the 

 blood of animals affected by it, and their destruction can hardly 

 fail to be advantageous. A¥e are, therefore, not at all surprised 

 to learn that Bouley and the French Commission found* that, 

 while all animals which they inoculated with this disease died 

 when left to themselves, four recovered out of five to which 

 they had given carbolic acid, and that other cases treated in the 

 same way by others gave a like favourable result. The striking 

 correspondence between the effect actually produced on the 



* Com_pt. rend., vol. Ixviii, p. 82. 



