No. 76. J 131 



I have also to add, that Dana {Mineralogy^ 2d ed., p. 383,) gives a 

 figure of a crystal of chondrodite, drawn from a specimen in the col- 

 lection of J. A. Clay, Esq., of Philadelphia, and obtained in Orange 

 county, New-York. 



PVROXENE. 

 (Mineralogy ot New- York, page 286.) 



A fine locality of this mineral has been found in the towii of Fine, 

 St. Lawrence county. The crystals, though not perfectly smooth, are 

 still well formed, and more than a yard in length I Emmons^ Jour, of 

 Agriculture, in., p. 156. 



Pyroxene, as is well known, presents a great variety of forms ; distinct 

 names have been applied to many of these varieties, and some have even 

 been described as distinct species. The researches of mineralogical 

 chemists have resulted in the reduction of many of these supposed dis- 

 tinct minerals to one species. Dana has, I think, carried this further 

 than any author ; for he not only places under pyroxene, diopside, pyr- 

 gom, fcahlite, coccolite, jeffersonite, and hedenbergite, in which I concur, 

 but he also ranges with it diallage and hypersthene ; concerning the 

 propriety of which I still have much doubt. If this wide scope is given 

 to the mineral in question, there seems to be no reason why its limits 

 should not be still further extended, and made to embace many other 

 species. 



Hudsonite, proposed in the Mineralogy of New- York as a new species, 

 (p. 405) is thought by Dana to belong to the pyroxene family, and to be 

 very near to hedenbergite. It is certainly more closely allied to the latter 

 mineral than to any other, although it is remarkable for the large per 

 centage of oxide of iron which it contains. The circumstance of its 

 being found in a gangue of quartz, from which it is easily separable, 

 induced mc to believe that this was not an accidental ingredient. I 

 regret that 1 have not yet obtained any specimens which admit the de- 

 termination of its crystalline form, as this would conclusively settle the 

 point in dispute. Its cleavages, as far as they can be determined, cer- 

 tainly resemble those of pyroxene. But chemical composition ought also 

 to have some weight in the determination of specific distinctions. No one, 

 however, who has a just appreciation of the true interests of science, 

 should hesitate to abandon an opinion which he has advanced, when it 

 is found to be inconsistent with facts subsequently made known. The 

 useless multiplication of species, and the introduction of arbitrary names 

 in natural history, is especially to be avoided. 



