836 General Notes. [October, 



It is found in two forms, the one massive, finely fibrous, grayish- 

 white and translucent ; the other as friable opaque tears slightly 

 colored by iron salts. It contains, as shown by Dr. Divers, 

 twenty-four molecules of water, and is thus of the normal type. 



A RELATION BETWEEN THE OPTICAL AND CHEMICAL PROPERTIES 



of Pyroxene and Amphibole. — F. J. Wiik has found a very in- 

 teresting relation between the optical and chemical properties of 

 the pyroxenes and amphiboles of Finland. The angle between the 

 axes of greatest and least elasticity has a direct relation to the 

 amount of ferrous oxide in pyroxene or the amount of alumina- 

 in amphibole, the angle becoming larger as the percentage of 

 these substances i 



Specimens from a large number of localities w< 

 with unvarying result. The following are example 



New Minerals.— Two new minera 



Is from Wermland, Sweden, 



are described by Igelstrom : 





M.ingaulmicite.— ms is a massive, 



uncleavable substance of a 



yellow or brownish-red color, which 





bedded in the manganese ore of th< 



2 Jakobsberg mines. It is 



associated with a number of mangan< 



jse minerals. It contains 



It a pure substance, and found to be of constant < 

 may be classed as a massive manganesian variety 

 Talktriplite.—'Ihis is also a massive substance c 



raly.is of 



the pure substance was made. It is si 



iplite con 



taining lime and magnesia, but furth 



ems to t 





ss. Itoc 



curs with lazulite, svanbergite and otht 



DlABANT 



ite-vermiculite. Professor B. K. Em 



diahuitit, 



c-venniadite from a dyke of diabase 



