124 Proceedings of the British Association. 



appeared to Dr. Inglis to arise from one cause. Many cases, to prove 

 convertibility of the one disease in the other, were adduced. Dr. Inglis 

 having full faith in the efficacy of vaccination and of re-vaccination, after 

 first inserting the vaccine lymph, inserted into his arm in several places, 

 the virus from variolous patients in different stages of the disease, and 

 in one instance, from a patient who was dying from the disease, but in 

 none of them did he succeed in inducing an eruption : the inflammation 

 and pruritus was considerable for a day or two, but then gradually sub- 

 sided. That the vaccine virus, tberefore, decreases in its preventive in- 

 fluence is a supposition at least difficult of proof, for, from the begin- 

 ning, this prophylactic power was imperfect in different degrees, and 

 even an attack of small-pox itself, is no certain security against a second 

 or even a third attack. The next point in the paper was to show that 

 the two visitations of small-pox and vaccination could and did go on in 

 the system at one and the same time, distinct cases of which were brought 

 forward. Now, since two dissimilar contagious irritations cannot run 

 their course together without the one impeding the other for a time, Dr. 

 Inglis was led to suppose that vai'iola and variola-vaccinia bad the same 

 common origin, or rather that vaccinia sprung from variola. The paper 

 concluded by the following brief summary: — 1st, That small-pox is de- 

 cidedly on the increase, and that during each successive epidemic there 

 is an increase of variolous patients from amongst those who were vac- 

 cinated in infancy. 2nd, That the vaccine virus is as effectual now as 

 ever it was, but that re-vaccination is necessary after a period of years, 

 is yet unknown. 3rd, That the same cause which produces small-pox 

 duriug a variolous epidemic in the unvaccinated, may and does give rise 

 to chicken-pox in the vaccinated. And 4th, That there is every reason 

 to believe that cow-pox had its origin in variola. 



' On the new Vaccine Virus of 1838,' by Mr. J. B. Estlin. — The paper 

 stated that the author had procured some fresh vaccine lymph from the 

 cow in August, 1838, and that in consequence of much dissatisfaction 

 among medical men with the matter previously supplied by the National 

 Vaccine Establishment, numerous applications were made to him for the 

 new lymph, and that it soon became extensively employed. The object 

 of the present communication was to show, that the powers of the new 

 virus diminished in intensity as successive vaccinations increased its 

 distance from the cow. The author had watched it through forty-eight 

 subjects in succession, and for nearly twelvemonths. During the first 

 three or four months, rather severe local and constitutional effects follow- 

 ed. During the latter months, however, of the year of trial, the activity 

 of the matter had greatly diminished ; while the vesicle at the present 

 moment produced by it retains all the characteristics of perfect cow-pox, 

 as described by Jenner. The author also referred to some experiments 

 lately made by Mr. Ceely, of Aylesbury, in which cows were inoculated 

 with the matter of small-pox, the result of which was, the appearance of 

 the regular vaccine vesicle upon the inoculated part of the animal. From 



