184 BACTERIA. 



theory was at once accepted as being from every point of 

 view more far-reaching and more satisfactory than the older 

 one which explained all the symptoms by referring them to 

 loss of water through the excessive intestinal discharges ; a 

 symptom or effect was, in fact, looked upon as the cause of 

 other symptoms. The earlier observations on ptomaines and 

 sepsines, and Pasteur's and Hansen's later observations on 

 ferments, naturally led to a search being made with the 

 object of finding out any specific products of the cholera 

 organism. Koch himself records the fact that he succeeded 

 in preparing cultures of the comma bacillus which were so 

 intensely poisonous, that when injected into animals, either 

 subcutaneously or into a peritoneal cavity, there were set up 

 in a few minutes all the symptoms which occurred- in 

 animals suffering from cholera a day or two after infection 

 u paralytic weakness of the hinder extremities, coldness of 

 the head and legs, and prolonged respiration, a condition 

 which usually leads after some hours to death." Buchner, 

 who demonstrated, as he believed, the formation of butyric 

 acid during the growth of pure cultivations, was unable to 

 corroborate by any experiments of his own this view of 

 Koch's, but Pouchet and Villiers were both able to extract 

 from the dejecta or from the organs of cholera patients cer- 

 tain products which they deemed to be characteristic. 



The former, with the aid of chloroform, extracted from cholera dejecta an 

 extremely toxic oily liquid which, as it becomes oxydized in the presence of 

 air and light, takes on, first a rose, and then a brown colour. It readily 

 combines with hydrochloric acid to form a chloride, but again breaks down, 

 in vacua, or when the temperature is raised, or on the addition of an alkali. 

 It gives the reactions characteristic of the alkaloids, and gives the blue re- 

 duction coloration with ferro-cyanide of iron and perchloride of iron. 

 Villiers succeeded in separating from the organs of a single cholera patient 

 a couple of centigrammes of a peculiar alkaloid. On treating this with 

 hydrochloric acid, there separated out a number of acicular crystals : these 

 crystals have since been described by various observers, and it is stated that 

 in this form the basic substance, whatever it may be, exerts comparatively 

 little poisonous action, but that as soon as it is again set free from the acid 

 combination, by the addition of an alkali, such as soda or potash, it exerts 

 not only an extremely caustic local action, but also when injected into a 

 guinea pig produces muscular tremblings and very great irregularity of the 

 heart's action, the animal dying at the end of about four days. It is im- 

 possible, however, to be quite certain that these reactions were obtained with 

 Villiers' pure acicular crystals, and not with one or other of the sepsines or 

 toxines, as there is some little doubt as to the exact nature of the poison 

 obtained in several of the series of experiments. Brieger, going beyond 



