a New Mineral Species. , 329 



3.27, whereas in fact it is much lower, and comprehended with- 

 in the Umits assigned to the species by Professor Mohs, namely, 

 2.5... 2.6. The result of a late experiment, which I tried with 

 very pure crystals, is 2.592. The numbers 3.2741 are given 

 in the first edition of Hauy\s Traite, and by most subsequent 

 authors ; but they cannot refer to nepheline. 



The authors of the Prodromo obtained the following result 

 by chemical analysis of this species. 



96.89 



Hence they infer that Davyne consists of one atom of bisilicate 

 of lime, five atoms of silicate of alumina, and two of water, 

 giving the formula CS^ -f- 5 AS + 2 dq. It forms a jelly 

 with nitric acid, froths before the blowpipe, and altogether 

 shows the phenomena corresponding to its contents. 



The preceding statements, as far as they refer to the account 

 given by Messrs Monticelli and Covelli, were taken from the 

 , translation contained in Silliman's Journal for October 1826, 

 as I have not had the advantage of comparing the original. 



All the characters of Davyne, and the general aspect of the 

 substance itself, concur in assigning to it a place among the 

 numerous family of the zeolites, that is, in the genus kouphone- 

 spar of the system of Professor Mohs. As a systematic denomi- 

 nation, that of the Davyan koitpkone-Sjpar seems very appropri- 

 ate ; and it retains the allusion to the illustrious individual, 

 in whose honour the name of Davyne was proposed. 



There is a peculiar charm attached to every novelty, parti- 

 cularly if the new object, like a species in mineralogy, bears so 

 large a proportion to the whole contents of a natural kingdom. 

 Next to this is the interest of contributing towards the more 

 firm establishment of a fact but lately discovered, and from tliis 

 point of view I believe the preceding account will not be consi- 

 dered quite superfluous. 



VOL. VII. PART II. OCT. 1827. Y 



