1832.] Proceedings of Societies. 159 



during the action of the drill ; so that the aid of an assistant to the operator is not 

 required- Dr. Casanova stated to the Society, that he has now a case of Urinary 

 Calculus, under treatment by Civiale's process, and he exhibited some portion of 

 the stone which had been reduced to a powder by the first operation, on this sub- 

 ject. A chemical examination made by the President, proved this to be composed 

 principally of carbonate of lime, with some phosphate of lime, and scarcely any 

 lithic acid : a very slight trace of iron was apparent, probably from attrition of 

 some particle of the Lithontriteur. Dr. Casanova also presented to the Society, 

 the fragments of a stone on which he had successfully operated at the Mauritius ; 

 and he offered his apparatus, made after Civiale's model, for the use of any of the 

 professional men at the Presidency, who might require it either for operation, or 

 to have a similar apparatus made here. 



7. A letter from Mr. Royle, on his departure from Calcutta, presenting for 

 the Library six medical works, viz. 



Dionis's Surgery. 



Le Dran's Surgery. 



Lommiusde Febribus. 



Sennertus, Epitome Institut. Medicianse, cum libro de Febribus. 



Albertus Magnus de Morbis Mulier. 



Michaeli's Scotus, Opusculum de Secretis Naturae. 

 The following papers were then read and discussed by the Meeting : 



The case of disease of the heart formerly presented by the Medical Board. 



Dr. Casanova's case of Elephantiasis. 



Mr. Mercer on Small-pox after vaccination. 

 This paper commences with a few remarks on the occasional occurrence 

 of small-pox oftener than once in the same person; the author then observes, 

 that although the greatest benefits have been derived from vaccination, (the 

 efficacy of which generally as a preventive of variola he fully acknowledges,) still 

 it must be allowed, that sometimes a modified small-pox occurs after vaccina- 

 tion ; and in few very rare instances, the severer forms of confluent small-pox hap- 

 pen. Seven cases of variolous and varioloid disease have recently fallen under 

 the author's observation, the particulars of which he now placed before the So- 

 ciety ; from consideration of these cases, he concludes, that the varioloid disease, 

 after vaccination, occurs in a great variety of forms, and with considerable diver- 

 sity in its eruptive symptoms, as well as in the degree of intensity of the attendant 

 pyrexia. He is also inclined to believe, that some individuals who have been for 

 a time protected against variola by vaccination, may become afterwards liable to 

 suffer from the former disease ; although the present cases would not support 

 a conclusion that there was any particular period at which the prophylactic pro- 

 perty of vaccination ceased ; as the patients he has lately treated, while suffer- 

 ing from varioloid diseases, were aged respectively, 29, 28, 22, 20, 19, 13, and 

 seven years ; they were vaccinated in infancy, and there is no evidence that any 

 of them had in the interval been exposed to variolous contagion. 

 Mr. Hutchinson on the Proximate Cause of Cholera. 



Mr. Hutchinson attempts to explain the mode in which the phenomena of 

 that disease are produced. The idea of its depending on inflammation in the in- 

 testinal canal, (even were it shewn that an affection of that nature is invariably 

 present, in the early stage of the disease, which it is not,) he considers totally 

 inadequate to account for the phenomena. Mr. H. conceives Cholera to depend 

 on a certain state of disorder of the functions of respiration, whereby the change s 



