THE IIAWLKY iSClllS'J'. 



1()7 



a = brifjht yellow, b>c>a. The colorless ))hen<)ervsts are small, siiioje 

 twins of alhite, extiugiiisliiii<>- at about 2° on either side the center. With a 

 lens they are seen to be frosted full of small grains of epidote, and scales, 

 apparently of muscovite. With polarized light these make a mosaic of such 

 brilliant color that only a trace of the polarization of the feldspar is visible. 

 In a section parallel to zcVcc (100) a negative ol)tuso bisectri.x was 

 observed. The large rhombs of ankerite with rust-marked cleavages ap])ear 

 everywhere. Magnetite is abinidant in small, rounded grains without alter- 

 ation ])roducts. The background is a mosaic of small, short hornl)len(le 

 blades and magnetite, epidote, and fel(lsi)ai- grains. It forms most beautiful 

 microscopic slidc-s. 



Black, fissile ampliiboHU' from Wt)rthington, west of (J. Sherman's. 

 Nearly all a network of large blades of hornblende, with finely marked 

 prismatic cleavage Hiis has medium pleochroism and the fornuda c — 

 blue-green, b = yellow-green, a = yellow: c>b>-a. Titanite and appar- 

 ently zircon appear. 



The anah'sis of this rock was made by Mr. T>. O. Eakins. 



Anali/sis of (tmphihoUtc from Worihiiu/toit. 



SiOi. . 

 TiO.2 . 



Al.O:, 



Fe.O:, 



Per cent, 

 48. .53 



2.03 



FeO 10.52 



MnO .17 



BaO trace 



9.83 

 9.71 



CaO . 

 MgO, 



H,0. 

 P.Ov 



1.7 



.07 



The Heath amphihoUte hed. — Across Heath from north to south, witliin 

 tlu; border of the Goshen schist, runs a band, standing n.earl\- vertical and 



