A CONTRIBUTION. 
197 
- v same. Aside from the circumstance that sheep can be success¬ 
fully inoculated with vaccine, and that the ovine organismus pos¬ 
sesses the peculiarity, that it frequently generalises the vaccine, 
there is no nearer relationship between v. ovina and v. vaccina. 
The vaccinated disease of sheep is not identical with variola ovina: 
were it so, there must necessarily take place accidental transmis¬ 
sions of v. ovina to cattle of every sex and age, which is in fact 
not the case. 
The only remaining forms of variola, in which we may seek 
the genesis of the bovine variety, are variola humana vera and 
the artificial (variolated) protective variola of man; so that I feel 
myself justified in formulating the following axiom, to which we 
have arrived per exclusion. 
The origin of the so-called “ original ” or true bovine variola , 
variola vaccina—can 07ily lie in the human vaccina or variola. 
That variola humana vera inoculated upon cows is able to 
generate variola vaccina, is proven by the experiments of Gasner, 
Sunderland, Theile, Ceely, Badcock, and others, to which I must 
more intimately refer on account of their fundamental impor¬ 
tance. 
According to the data given by Bohn, (“ Handbuch der vaccin¬ 
ation,” Leipzig, ,1875), the first experiment of this kind was made 
by Gassner, in 1807, in Guenzburg, who inoculated several cows 
with variola from children, and received positive results, that is, 
by eleven cows, variola vaccina developed, and from the last lie 
vaccinated four children, and received very fine inoculatory 
pustulae. 
The greatest credit in this question belongs undoubtedly to 
Thiele in Karan, 1836, and the Englishman Ceely, 1838. They 
inoculated cows with the lymph from human variola upon the 
udder and vulva, and received thereby true variola vaccina, local¬ 
ized upon the place of inoculation. In no case did there develop a 
general exanthema by the inoculated cows. 
The so generated artificial variola vaccine, or better-vaccin 
ated variola, deports itself by further inoculation in exactly the 
same manner as the so-called original cow or vaccine lymph. The 
pustule has the greatest virulence from the sixth to tenth day, and ex- 
