601 



February 12, 1846. 

 GEORGE RENNIE, Esq., Treasurer and V.P., in the Chair, 



" A Practical Extension of the application of the La^' of Mor- 

 tality announced by B. Gompertz, Esq., in the Philosophical Trans= 

 actions for 1823." By A. M. Drach, Esq. Communicated by B. 

 Gompertz, Esq., F.R.S. 



In endeavouring to verify the theoretical law of mortality, an- 

 nounced by Mr. Gompertz, by means of constants derived from the 

 results of the English census of 1841, Avhich are contained in the 

 sixth Annual Report of the Registrar-General, and which furnish an 

 extended basis for computation, the author found the accordance 

 between the two to be so remarkably close as to justify the assump- 

 tion that Mr. Gorapertz's formula expresses the true law of the de- 

 crement of human life. The paper is occupied with the analytical 

 details of this investigation. 



" On Spontaneous Nitrification." By C. F. Schcenbein, Professor 

 of Chemistry in the University of Bale. Communicated by Michael 

 Faraday, Esq., D.C.L., F.R.S., &c. 



From various facts adduced by the author, he is led to the con= 

 elusion, that during the slow combustion of phosphorus in moist 

 atmospheric au', while ozone is produced, there is also formed a 

 quantity of nitric acid ; and that in all cases where both these com- 

 pound bodies are simultaneously generated, however different may 

 be the concomitant circumstances of the experiment, there is strong 

 reason to suspect that the formation of the one is in some way con- 

 nected with that of the other. 



" On the Process of Etching, or Engraving, by means of Voltaic 

 Electricity." By James H. Pring, M.D. Communicated bv P. M. 

 Roget, M.D., Sec. R.S. 



The author, referring to an account which he gave of his method 

 of etching on hardened steel plates, or other polished metallic sur- 

 faces, by means of electricity, in the Philosophical Magazine for 

 November 1843, offers some additional observations relating to the 

 theory of the process, and states some further practical remarks in 

 its application to engraving. A specimen of a steel plate, and of a 

 razor, on which ornamental designs were engraved by this method, 

 were laid before the Society, in illustration. 



February 19, 1846. 



The MARQUIS OF NORTHAMPTON, President, in the Chair. 



James Matheson, Esq., \yilliam West, Esq., and John Wilson, 

 M.D., were elected Fellows of the Society. 



" On the Mechanism of Respiration." By Francis Sibson. Com- 

 municated by Thomas Bell, Esq., F.R.S. 



This paper is almost entirely occupied with anatomical details, 

 collected from an extensive series of dissections of the muscles and 



