474 PETROLOGICAL ABSTRACTS AND REVIEWS 
WHeErRRY, Epcar T. “The Microspectroscope in Mineralogy.” 
Smithsonian Miss. Col., LXV (1915), No. 5. Pp. 16. 
Descriptions of the spectra observed in the examination of about 
200 minerals with the microspectroscope. 
Witxman, W. W. “Kaleviska bottenbildningar vid Mélénjarvi.” 
Bull. com. géol. Finlande, No. 43, 1915. Pp. 36, figs. 11. 
A geological description of the basal formations near Lake Mdélén- 
jarvi, in east Finland. Granite, conglomerate, quartzites, various’ 
schists and phyllites, and basic dikes are described. 
Wricut, FRED. EuGENE. ‘An Electrical Goniometer Furnace 
for the Measurement of Crystal Angles and of Refractive 
Indices at High Temperatures.” Jour. Wash. Acad. Sci., 
III (1913), 396-401. 
Describes a furnace for measuring the interfacial angles and refrac- 
tive indices of crystals at temperatures up to 1225°. 
WRIGHT, FRED. EUGENE. ‘‘Graphical Methods in Microscopical 
Petrography,”’ Amer. Jour. Sci., XXXVI (1913), 509-39, pls. 
8, figs. 9. ; 
The writer gives eight charts for the solution of the following equa- 
tions: sinz=# sin r, sin? 7=n? sin?r, cot A= B.cot C, sin A=sin B. sin C,. 
ca Ege 
ee 2, 2 2 a2 
Z - sin Grasin Gai tan2 Vie tan Va= neneg : 
= Te ior I 
oe \enP 
WriGuHT, FRED. EUGENE. ‘‘The Change in the Crystal Angles of 
Quartz with Rise in Temperature,” Jour. Wash. Acad. Sct., 
III (1913), 485-94, figs. 2. 
The polar angle p of the unit rhombohedron was found to decrease 
at an increasing rate until the temperature of 575° was reached. Here, 
with the inversion of a-quartz to B-quartz there is an abrupt decrease 
of 2’ in the angle, and the value remains constant thereafter to 1250°. 
