5o8 HYDROPHOBIA. 



the natural period of incubation was shortened. Further, 

 the identity of the furious and paralytic forms was proved, 

 as sometimes the one, sometimes the other, was produced, 

 whatever form had been present in the original case. 

 Inoculation into the anterior chamber of the eye is nearly 

 as efficacious as subdural infection. Infection with the 

 blood of rabic animals does not reproduce the disease. 

 There is evidence, however, that the poison also exists in 

 such glands as the pancreas and mamma. Subcutaneous 

 infection with part of the nervous system of an animal dead 

 of rabies usually gives rise to the disease. 



In consequence of the introduction of such reliable 

 inoculation methods, further information has been acquired 

 regarding the spread and distribution of the virus in the 

 body. Gaining entrance by the infected wound, it early 

 manifests its affinity for the nervous tissues. It reaches 

 the central nervous system chiefly by spreading up the 

 peripheral nerves. This can be shown by inoculating an 

 animal subcutaneously in one of its limbs, with virulent 

 material. If now the animal be killed before symptoms 

 have manifested themselves, rabies can be produced by 

 subdural inoculation from the nerves of the limb which was 

 infected. Further, rabies can often be produced from such 

 a case by subdural infection with the part of the spinal cord 

 into which these nerves pass, while the other parts of the 

 1 animal's nervous system do not give rise to the disease. 

 This explains how the initial symptoms of the disease 

 (pains along nerves, paralyses, etc.) so often" appear in the 

 infected part of the body, and it probably also explains the 

 fact that bites in such richly nervous parts as the face and 

 head are much more likely to be followed by hydrophobia 

 than bites in other parts of the body. Again, injection 

 into a peripheral nerve, such as the sciatic, is almost as 

 certain a method of infection as injection into the subdural 

 space, and gives rise to the same type of symptoms as 

 injection into the corresponding limb. Intravenous injec- 

 tion of the virus, on the other hand, differs from the other 

 modes of infection in that it more frequently gives rise to 



