1815.] Royal Inst'ilule. 45* 



Ou the east side of the range of rocks aljove described may be 

 seen a conglomerate (being one of the forms of the old red sand- 

 stone) resting immediately on the slate, and itself serving as the 

 basis for the great lime-stone deposit which crops out in Cross Fell 

 and forms a parallel range to the slate and green-stone. On the 

 western side, however, of this latter range, a very different series 

 of rocks displays itself. First occur strata of lime-stone, either by 

 themselves or with their seams of coal interposed, elevated at a hi<Th 

 angle approaching to vertical, and much broken. Then comes iiTa 

 sand-stone in nearly horizontal beds, extremely diiferent from the 

 conglomerate already mentioned, and, in the opinion of the author 

 of this paper, forming a part of the great deposit which ove spreads 

 the vale of Carlisle, a large part of Cheshire, and the vale of York, 

 and in which are found the great quarries of gypsum and the beds of 

 rock salt, a deposition more recent than tiie magnesian lime-stone 

 which^ is incumbent on the upper strata of (he principal English 

 coal-fields. 



ROYAL INSTITUTE OF FRANCK. 



Account of the Labours of the Class of Mathematical and Physical 

 Sciences of the Royal Institute of France during the Year 1814. 



I. Physical Department. By M. le Chevalier Cuvier, Perpetual 



Secretary. 



Chemistrv. 



One of the most curious substances lately discovered is iodine, a 

 substance long concealed in kelp, which by heat is converted into 

 a beautiful violet vapour, and which, acting on other bodies in a 

 manner analogous to chlorine, has given new force to the notions 

 originating from the nature of sulphuretcd hydrogen and from that 

 of chlorine — notions tending to introduce into the theory of 

 chemistry that important modification that oxygen is not the only 

 principle capable of producing acidity. 



In fact, Herthollet had shown about 30 years ago that snlpliureted 

 hydrogen, though it contains no oxygen, possesses all the properties 

 of acids; and the German chemists had dwelt very mucli upon this 

 fact in their disputes with the French chemists. J\'jiM. Thcnard nnd 

 (Jay-Lussac made experiments in 1H09 showing (hat it isim()osHble 

 to extract oxygen from what was called oxyinuriatic acid ; and that, 

 if it contaiii:, <'xyj,'inj ^ve must supj)ose, that in all cases when it is 

 converted into common muriatic acid, water is formed, which 

 unites, and cannot be separated from the acid profliiced, or at least 

 that the elements of the water enter into the aeid as constituent 

 parts ; while on (he other hand, liy regardii]g oxymnriatic acid as a 

 simple substance which forms muriatic aeid by eoinbining with 

 hydrogen, (lusc supposidons are rendered unnecessary. Hut tliou'h 

 our two chemists stated these two Iiypothescs, they adhered to the 



