A CONTRIBUTION. 
199 
passing through the ovine organismus again assumed its original 
properties—that is those of the contagium of v. hum ana vera. 
We are not without reports of negative results, which stand 
opposed to those we have just considered. Reiter received only 
negative results from his variola inoculations upon cattle. A 
commission in Lyons, composed of Chauveau, Wennois and Mey- 
net, 1865, basing themselves upon the results of their experiments, 
that the organismus of cattle is incapable of transforming the 
variola of man into vaccine, but that the same produces again 
only bovine variola, which presents itself as a simple pustulous 
eruption. A similar result was obtained by a Turin commission 
187l-’74, viz : Human variola is not to be transmitted to cattle. 
As by all such questions, negative results cannot do away with 
a large succession of positive experiments, and it is undoubtedly 
necessary that many circumstances must happily unite in order to 
produce positive results. As Bohn says, it is as essentially de¬ 
pendant upon the manner of inoculation as upon the animals 
selected. How else shall we explain the positive results obtained 
by Senfft with his calves? An analogy to the same is in a cer¬ 
tain way offered by the retro-vaccination of man. While many » 
observers assert that they have met with great assistance on the 
part of the human organism against retro-vaccination, other ex¬ 
perienced experimenters, as Reiter, Kranz and others, have almost 
always received positive results. 
We can happily strengthen our conclusions, and the above 
noticed positive results which go to prove the causal-nexus be¬ 
tween v. humana and v. vaccina, by carefully observed and re¬ 
corded proofs of the accidental (not experimental) transmission of 
the human form of variola to the bovine organismus. 
Ceely, the exact and trustworthy English observer relates in 
his book with almost painful exactness the following case: In the 
vale of Aylesbury the cows of a stable had opportunity to smell 
and lick the bedding of a person who had died of variola, which 
was spread out to air on the grass of a meadow. The cows grazed 
in this place and in the course of twelve or fourteen days, variola 
vaccina broke out by five of them, almost at the same time, and 
this was accidentally transmitted to them, the owner and milker 
