REVIEW. 91 



Cohn succeeded in producing splenic fever with any other species 

 of Bacillus. 



That Bacillus antJiracis can produce splenic fever when 

 injected into the circulating nutrition of the body is now abun- 

 dantly clear. In addition to this, Koch tried whether the diges- 

 tive or respiratory organs could be made the means of poisoning 

 by this form. Mice and rabbits both ate either form of this 

 species with impunity. As to the results of the inspiration of 

 them, no satisfactory experiments were made. 



The results of Branell^ on the influence of the filtering action 

 of the placenta were confirmed. To see how soon the poison 

 took effect, nine mice were simultaneously injected with it, and 

 examined after two, four, six, eight, ten, twelve, fourteen, and 

 sixteen hours respectively. No Bacilli were found in the first 

 six ; the spleen alone of the seventh was affected ; in the eighth 

 this organ was enlarged, and the Bacilli more numerous. The 

 ninth mouse died after seventeen hours of the disease, which was 

 accompanied by its characteristic symptoms. 



Two dogs, one partridge, and one sparrow, were injected with 

 the poison, but no splenic fever ensued in these experiments; 

 frogs also are not poisoned by the injection of fibres or spores of 

 Bacilli. Koch describes, however, the changes which took 

 place, when a piece of spleen which contained them was placed 

 under the skin ; but I do not think that I should be justified in 

 detailing the facts here. 



4. To fully know the setiology of splenic fever, we must know 

 much more than we do now. Can it be that ruminating animals 

 cannot eat the spores with impunity as rodents can ? Why is it 

 that these larger animals take days to die while mice die in 

 thirty hours ? What are the various influences exerted by 

 different degrees of temperature, depth of sepulture, humidity 

 of soil, in the formation of the spores ? Yet it is a subject 

 for congratulation that Koch has so distinctly shown that the 

 fibres, as compared with the spores, are comparatively harmless ; 

 let them remain dry for years, in decomposing fluids for months, 

 be repeatedly dried and as often wetted, still .do the spores retain 

 their baneful influence on living animal fluids. A wound, how- 

 ever slight, is sufficiently large to allow them to enter. Use 

 cotton wool to soothe a burn, and perhaps you are applying 

 yourself the seeds of the disease that will kill you ; bathe in a 

 stream in which they are resting, and a scratch will offer them a 

 way into your system. So much is clear; quite as clear, unfor- 

 tunately, is the enormous extent of their ravages ; in one small 

 Prussian district £9000 was lost by the death of sheep from this 

 disease; in three years the district of Novgorod lost 56,000 

 1 Cf. ' Quart. Jour. Mic. Sci.,' July, 1876, p. 274. 



