Itojal Society ef London. — Aerojlatlon. lof 



C. Rlpault, librarian, prefented a memoir, entitled lU- 



Jearches reJpeBing the Oajis. 



ROYAL SOCIETY OF LONDON. 



Since our lall report papers on the following fubjefts have 

 been read at the meetings of this learned body : — 



On a new Principle in Tanning, by George Biggin, Efq. 

 From the experiments adduced in this paper it appears, that 

 elm bark is the leaft powerful of any, and that oak bark 

 in winter is not fo powerful as in fpring in the proportion 

 of 30 to 128. 



On Lime employed for manure by Smythfon Tennant, Efq. 

 This paper contains much ufeful praaical information re- 

 fpeaing the effefts produced by different kinds of lime-ftones. 

 One kind, found near Doncafter, proves highly detrimental 

 to the land on which it is laid, however fparingly, fo as to 

 deftroy almoft entirely all vegetation: this mifchievous pro- 

 perty is found to be owing to the prefence of a portion of 

 magnefia. Near Ferry-bridge, on the other hand, a lime- 

 ftone is found which proves highly fertilizing applied in any 

 quantitv. This paper is accompanied with a table of diffe- 

 rent pernicious lime-ftones found in various parts of the 

 kingdom. 



The reading of a paper on the Decompofition of Borax by 

 Profeffor Crell, and an interelting one on Shells and Bones, 

 by Charles Hatchet, Efq. terminated the feffion, which was 

 clofed on the 13 th inftant. 



AEROSTATION. 



Several of the foreign journals have announced an inven- 

 tion of Profeffor Danzel for direaing an air balloon through 

 the atmofphere. The following is a fliort account of the 

 method. M. Danzel has conftrufted two cylinders or axles, 

 to the ends of which are fixed, in the form of a crofs, four 

 fails or oars, moveable at the point of their infertion into the 

 cylinder, in fuch a manner that, when made to move round 

 by mrans of a handle, the eight oars, like the cogs of a watcr- 

 5 "^^" 



