Pirssonand Washington — Geology of New Hampshire. 455 



Alkalic feldspar 20*0 



Plagioclase feldspar 27*2 



Hornblende .... 35'3 



Biotite 0-9 



Iron ore . 14*8 



Apatite 1 '1 



Total . 99-9 



In obtaining this a part of the rock was selected free from 

 inclusions to give the normal composition. On account of their 

 characters the feldspars conld not be accurately discriminated 

 and the two were measured together and their relative amounts 

 then estimated, the result being checked by the alkalies shown 

 in the analysis. Thus while their total amount relative to the 

 other minerals is nearly correct, their proportions to each 

 other are only approximate. The small grains of iron ore in 

 the feldspars could not be measured and a small amount was 

 deducted for them and added to the measured ore areas. The 

 apatite also could not be measured but is obtained from the 





I. 



II. 



III. 



IV. 



Si0 2 



. 52-95 



50-97 



52-85 



883 



Al t> 



.. 14-96 

 2-44 



1556 

 4-43 



13-25 

 2-36 



147 



Fe 2 3 



015 



FeO 



7'03 

 3-86 



7-62 



4-28 



8-71 

 6-84 



•097 



MgO 



•097 



CaO 



6-76 



7*05 



8-47 



•121 



Na 2 



4-95 



5-04 



4-72 



080 



K 2 <J 



1-64 

 0-55 ) 



1-26 



1-53 

 0-93 



•017 



H 2 110°+ ... 





H 2 OllO°- ... 



0-09 j 



1-58 







... 



co 2 



o-oo 











... 



Ti0 2 



3-90 



1-98 



0-35 



•049 



PO 



0'76 



0-43 



0-40 



•005 



s 2 J_ 



0-05 



0*16 







Zr0 2 



0-02 













MnO_. 



trace 



0*38 







BaO 



o-oo 









... 



Total.. 100*16 100-74 



100-41 



I. Hornblende-akerose (spessartite). Belknap Mts., N. H. 

 Washington analyst. 



II. Augite-andose (augite kersantite). Cordillera de Doiia 

 Ana, Coquimbo, Chile. (F. v. Wolff, Zeitschr. d. deut. Geol. Ges., 

 li, 1899, 529) ; Soenderop analyst. 



III. Hyperstbene-kilauose (basalt). Cerro San Miguel, Puebla, 

 Mexico. (Felix and Lenk, Beitr. Geol. Mex., ii, 1899, p. 215). 

 Hoppe analyst. 



IV. Molecular ratios of No. I. 



