ON AN APHTHOUS AFFECTION AMONG CATTLE. 113 
milking them, and who happened to have any cracks, cuts, or 
excoriations on either the hands or arms. It ought to be borne in 
mind, that it was only in persons who had never been vaccinated 
that these vesicles or pustules were developed to such an extent 
as to become confluent. In individuals who had been vaccinated, 
the appearance was confined to little red spots, and a slight 
itching.” A case thus authenticated can leave no doubt as to the 
existence of cow-pox in the course of the apthous epizootic ob- 
served by M. Levigny, nor, at least, of some affection bearing a 
very great analogy to vaccine. 
We must, however, point out an omission in the valuable paper 
by M. Levigny, an omission the more important, since it might, 
perhaps, have at once explained the cause of the contagion in 
some cases, and the non-contagion in others. Thus, for example, 
is it rational to admit : 
1st, That aphthae, accompanied by variolous pustules on the 
teats of cows are possessed of contagious properties. 
2d, That the herds (the greater number, according to M. 
Levigny) that had only been attacked with the pure and simple 
aphthous epizootic had not communicated it to other animals. 
We appeal to the recollections of our talented brother veteri- 
narian, and beg him, in the name of the best interests of science, 
to state, in the Recueil , wTiether the facts of contagion which he 
observed and has recorded have not been derived from subjects 
exhibiting the variolous pustule 1 His candid answer will serve 
both veterinary medicine and the public hygiene. 
To return : Thus it is seen, that there are three distinct parties : 
those who consider aphthous affections to be contagious; those 
who do not absolutely deny the contagion, or admit that it might 
exist under certain circumstances ; and those who do not believe 
the disease to be contagious. 
Being extremely desirous of elucidating this question of sanitary 
police, we have made it the object of an attentive and conscientious 
examination. We have collected a number of cases that appear 
to us so positive, so conclusive, that they who peruse them will 
no longer hesitate, with us, to join the non-contagionists. The 
difference of opinion existing on the subject does not appear to us 
at all inexplicable ; nor is it remarkable that authors should 
have attributed contagious properties to aphthae appearing in con- 
cert with certain typhoid or charhonaceous affections, or that they 
should have been thrown into doubt when they saw them presented 
to their eyes under the form of phlyctaenae on the mouth or feet. 
The former phenomenon is likely to have presented itself more 
than once, at a period when the land was partly uncultivated, and 
