Diseases of the Nervous System. 249 
taking place previous to the manifestation of the first symp. 
toms, is a matter of pure hypothesis. The venom of the 
cobra, hydrocyanic acid, strychnine, and other poisons, pro- 
duce effects more or less prompt and decided, according 
to the amount introduced into the body of any animal, 
and we can exactly prognosticate not only the result, but 
the time about which it should occur. The virus of con- 
tagious diseases, and more particularly hydrophobia, differs 
from these, inasmach as a minute quantity is as potent in 
inducing its particular malady, in a certain time, as a large 
quantity ; and in the special disease now under considera- 
t'on it may lie in a Jatent condition for a long period with- 
out affording the slightest indication of its presence.”* 
Duration — The duration of rabies is rarely long—from 
one to ten days may be taken as the two extremes. A 
few cases have been noted over the latter period ; but they 
are very exceptional instances, and attended with some 
degree of doubt. Those in my own experience have been 
from four to five days; most of them have died on the 
fifth. 
Fleming observes : “The progress of rabies in the dog 
is always very rapid, and the termination, it may well be 
said, invariably fatal.” 
Its duration in no case appears to have exceeded ten 
days ; and in the majority of instances death takes place 
about the fourth, fifth, or sixth day after the appearance 
of the first morbid symptoms. Of course, it also occurs 
much earlier. Out of several tables we will only refer to 
those of Professors Saint-Cyr and Peuch, of the Lyons 
School, as they afford a fair idea of the duration of the 
disease in a number of cases. In 1864, fifty-four rabid 
dogs were reported. Death took place at the following 
periods : 
* Fleming’s “ Rabies and Hydrophobia,” pp. 165, 166. 
