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IX. Remarks concerning the Natural-Historical Determination 

 of Diallage. By W. HAIDINGER, Esq. 



(Read November 3. 1823.; 



JL HE following paper contains the results of a series of inquiries, 

 which lead to the conclusion, that the mineral called Smaragdite 

 by SAUSSURE, does not form a species of its own ; but that this 

 name has been given to a compound of certain varieties of two 

 distinct species, Augite and Hornblende, the natural-historical 

 species ofparatomous and hemiprismatic Augite-spar. 



Owing in part to the slight degree of resemblance prevailing 

 among its varieties, the authors who have described them differ 

 so essentially in opinion, that I am obliged to go into va- 

 rious details, both respecting the external appearance of the mi- 

 neral itself, and of the opinions of mineralogists, in order to 

 afford a correct view of the natural-historical species, to which 

 these varieties belong, since this is the basis upon which every 

 system, and, indeed, all accurate information in natural history, 

 is founded, and the fixed point to which the one and the other 

 must be referred. 



The more particular objects of these examinations are the 

 grass-green, and such other green and greenish-grey varieties as 

 are found to be in immediate connexion with them in the same 

 identical specimens. A connexion between the real Smaragdite 

 and the foliated Anthophyllite of WERNER, or the Schiller-spar 

 of the Hartz, does not exist, and has been gratuitously assumed 

 by the Abbe HAUY, and by other mineralogists. 



There is scarcely any thing which tends more evidently to 

 prove the homogeneity of individual bodies, than the transi- 

 tions between them, if correctly ascertained ; but we must not 



