2[12'. Proceedi/igs of Philosophical Societies, [April, 



Article XVL 



Proceedings of Philosoplucal Societies. 



ROYAL SOCIETY. 



March 8. — On the Length of the Second's Pendulum in dif^ 

 ferent Latitudes, by (.^apt. feabine. 



March 15. — Observations on Napthalin, by Dr. Kidd. 



March 21. — On the Papyri of Herculaneum, by Sir H. Davy. 

 . At the same meeting two other papers were read, viz. On the 

 Aberration of compound Lenses, by Mr. Herschel ; and On the 

 Skeleton of the Dugong, by Sir E. Home. 



An account of the contents of the above papers will be given? 

 in the next number. 



GEOLOGICAL SOCIETY. 



Jan. 14. — The Catalogue Raisonnee of the Collection of Swis» 

 Kocks, sent by M. Lardi, was read. 



The great valley comprehended between Mount Jura and the 

 Alps, and which forms the lowest part of Switzerland, is com- 

 posed partly of an alluvium, and partly of a sandstone and pud- 

 dingstone, in Switzerland, called Nagelflue, which signifies, 

 literally nail-head-rock. The alluvium consists of insulated 

 masses of primitive rocks, rolled pebbles, and debris, from the 

 surrounding mountains ; in this are also beds of clay. 



The nagelflue may be divided into two parts ; the molasse- 

 and the nagelflue, properly so called. The first is a sandstone 

 used for building in that country ; it is disposed in horizontal 

 beds alternating with beds of marie, which sometimes contain 

 marine shells and veins cf fibrous gypsum : the lower part has 

 beds of fetid bituminous limestone with freshwater shells, and 

 thin layers of coal. 



The nagelflue consists of a conglomerate of rounded pebbles- 

 of limestone united by a cement of the same nature; it forms a 

 mass of 30 or 40 feet in thickness, and contains also beds of 

 marie, and, occasionally, of coal. This appears to rest upon the 

 calcareous rocks of the Alps. 



The greatest part of Mount Jura consists of calcareous rock, 

 which is usually compact, and of a yellowish colour ; some of the 

 beds are oohte. It incloses numerous marine shells. The beds 

 of Jura dip on both sides of the chain. There is found here also 

 a formation of clay ironstone, which extends nearly all the length 

 of the Jura, and which supplies many foundries. 



The Alpine limestone is considered as a transition formation ; 

 it is of a compact texture, of a greyish colour, and frequently 

 contains nodules of flint. It rests on another limestone which 

 alternates with slate. 

 . The saliferous district of Bex has been well tiescribed by M. 



