On Rabies. 



85 



XI. Conclusions. 

 By these experiments it is shown : — 



(1.) That the virus of rabies in the lower animals, and of hydro- 

 phobia in man, resides principally in the cerebro- spinal substance and 

 in the peripheral nerves, as well as in the salivary glands, in accord- 

 ance with the fundamental statement of M. Pasteur. 



(2.) That inoculation of this substance upon the brain of an animal, 

 by trephining, produces infective rabies in rabbits almost infallibly, 

 and with a much shorter and less variable incubation period than 

 after subcutaneous inoculation. 



(3.) That in an infected animal, the tissues do not become virulent 

 till towards the close of the incubation period. 



(4.) That rabies, however produced, in both dogs and rabbits, is 

 essentially a paralytic affection, the same disease in both animals, and 

 that there is no constant distinction between the so-termed dumb and 

 furious rabies in the dog. 



(5.) That the activity of the virus of street rabies generally is 

 increased, and becomes remarkably constant, by passing through a 

 series of rabbits. 



(6.) That the activity of the virus is shown by the duration of the 

 incubation period, to which it is inversely proportionate, and that this 

 circumstance may afford a means of determining the source of infec- 

 tion in case of death from rabies or hydrophobia. 



(7.) That of numerous drugs of different classes tried on the rabbit, 

 none have any constant effect upon the result of infection. 



(8.) That by subcutaneous inoculations with modified virus, as 

 practised by M. Pasteur, it is not practicable to confer immunity, even 

 against subsequent infection, upon rabbits ; and that with these 

 animals the intensive or rapid method of inoculation is very liable 

 itself to produce infection ; that the constitutional refractoriness 

 of the dog to infection with rabies by any method of inoculation, 

 renders it extremely difficult to judge of the results of remedial or 

 prophylactic measures with this animal, from a limited number of 

 experiments; and that it is by the statistics of the treatment that 

 the results in man must be judged, 



Finally, I must state that my experiments were not undertaken 

 with primary reference to M. Pasteur's statements, but that the 

 fundamental importauce of these so greatly modified and subverted 

 previous views upon this disease, that it necessitated my investigat- 

 ing them, with the result of confirming the conclusions of their author 

 in many essential points ; and that it is to his notable discovery of the 

 chief seat of the virus, with the constant and rapid effects, in the 



