1825. J Proceedings of Philosophical Societies. 385 



focus, which focus is above four inches in diameter, as I judge 

 by the eye, the whole surface is seen to be covered with ridges 

 of different degrees of brilhancy ; indeed I have never seen it so 

 conspicuously as in this manner. 



I remain, Gentlemen, yours very sincerely, 



.1. B. Emmett. 



P. S. In my last paper on the Mathematical Principles of 

 Chemistry, I have made calculations on the supposition that 

 gravity in the ultimate particles of matter is proportional to the 

 density and volume jointly, in making the selection of matter, I 

 omitted a problem which ought to have been at the commence- 

 ment, viz. that in this case, cohesion, and all corpuscular forces, 

 may be produced ; this follows as a corollary from the ordi- 

 nary problem in every treatise on Fluxions, " To tind the attrac- 

 tion of a corpuscle to a right line," or from Prop. 90, of Newton's 

 Princip. vol. i. ; by substituting an evanescent or elementary 

 prism : then the force becomes infinite in contact, and indeh- 

 nitely great, at indefinitely small distances. The corollary 

 admits of two cases; first, where the force acts in the direction 

 of the prism ; secondly, where perpendicularly to it. — J. B. E. 



Article IX. 



Proceedi>igs of Philosophical Societies. 



«OVAL SOCIETY. 



April 14. — M. Gay-Lussac was admitted a Foreign Member, 

 and Henry Harvey, Esq. a Fellow of the Society. 



The reading was commenced of a paper, entitled, " A Mono- 

 graph on Egyptian Mummies, with Observations on the Art of 

 EmDalrning among the ancient Egyptians ; by A. B. Granville, 

 .MD.FRS. 



April 2). — The reading of Dr. Granville's paper was conti- 

 nued. 



I.INNKAN .SOCIETY. 



March 1. — The readings of Dr. Hamilton's Commentary on 

 the thud part of the Hortus Malabaricus, and Messrs. Shep- 

 liard's and Whitear's Catalogue of Norfolk and Suffolk Birds, 

 were continued ; and on 



March l.>, the reading of the atter conmiunication was further 

 continued. 



ASTRONOMICAI, SOCIETY. 



April H.—X paper was read, "On the Results of Computa- 

 tions on Astronomical Observations made at Paramatta, in New 

 'Sew Series, vol. ix. 2 r 



