ttYDROPHOBlA. 3I7 



These latter correspond to some of the cocci described by 

 Gibier. 



From Babes' description of the larger organism growing in the deeper 

 parts of the gelatine, and also in vacuo, it is evident that the organism is 

 anaerobic ; other organisms (micrococci) grow on the surface in the form of 

 grey, yellowish, dry streaks, when they are in the form of large cocci arranged 

 in chains, or as curved spindle-shaped bacilli. In all these forms the 

 micrococci or rounded points within the bacilli are stained pinkish with 

 Loffler's methylene blue ; whilst the intermediate substance and the bodies 

 of the curved bacilli take on a blue tinge. Similarly, spindte-shaped curved 

 organisms have been found in the cerebral substance of rabbits and guinea- 

 pigs suffering from rabies ; whilst curved thick motile bacilli have been 

 found in the blood of rabbits during the stage of fever that precedes the 

 regular nervous symptoms of rabies ; the inoculation of such blood, how- 

 ever, seldom produces rabies ; in fact, blood from almost any rabid animal 

 produces few or none of the symptoms of ordinary rabies. Ptomaines 

 have been described as present in the nerve centres taken from rabid 

 animals, and it is claimed that with the separated poisons, symptoms 

 analagous to those of true hydrophobia have been produced, but the experi- 

 ments, although probably accurate, are as yet too few in number to allow 

 of their being very seriously discussed. 



It is, however, doubtful whether the real causal agent has yet been 

 observed. It appears to be quite as probable that one of the lower animal 

 protozoa, coccidia, psorosperms or the like, may be the real cause of the 

 disease as that a bacterium" stands in this relation to hydrophobia. In 

 the same way it has been suggested that the acute exanthemata from 

 which organisms have not as yet been in most cases successfully cultivated 

 may have a similai causa causans. 



It was very early determined that hydrophobia or rabies 

 never arises spontaneously ; the actual date at which the 

 implantation of the disease took place could easily be traced, 

 as it was found that in the human subject the outbreak of 

 the disease always bore a definite relation to some such 

 injury as the bite of a rabid dog, wolf, or cat, or it might be, 

 to the licking of an abraded surface by an apparently 

 healthy animal, especially a dog which afterwards was known 

 to develop symptoms of hydrophobia. 



This disease is not confined to man and the animals men- 

 tioned. It has been observed that rabbits, deer, guinea-pigs, 

 and even horses may be similarly affected. Although the 

 disease had been described most carefully from its clinical 

 point of view, and although the saliva of a rabid animal was 

 siipposed to contain a specific infective material which was 

 probably the cause of rabies, Hydrophobia or Rage, it was 

 not until 1880 that Pasteur set himself to study the virus of 

 this terrible disease. His first experiments were made with 



