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ANNALS NEW YORK ACADEMY OF SCIENCES 



This is but one of a long series of determined mixtures of crystalline 

 antigorite with the minerals above stated and with others in the widest 

 variation. They appear to me to afford no ground for the hypothesis of 

 definite isomorphous mixtures of two minerals, antigorite and amesite, 

 from one extreme of a regular series to the other, as claimed by Tschermak, 

 but to indicate the irregular mixtures of several minerals in commonly 

 associated development. 



" Deweylite." 



An unusual variety of the mineral from the United States, whose high 

 content of silica has never been explained. G. = 2,096. Analysis by 

 Thomson. 



" Bowenite." 



From Cumberland, Rhode Island. The reported formula: 2(MgO. 

 CaO)2. SiOj + SHjO (Dana). Analysis by Bowen. 



