jo" 
a7" 
60. 
. FELDSPAR ‘‘augen’ 
24 
6, Rose. 
c, Smoky. 
FELDSPAR. 
FELDSPAR and QuarRTz intergrowth forming ‘‘ Graphic 
granite.” 
in gneiss. 
. MUSCOVITE. 
. BIOTITE. 
Nos. 1 to 57 exhibited by the Mineralogical Depart- 
ment of Columbia University, through Prof. Thomas Eg- 
leston and Dr. Lea MclI. Luquer. 
. ORTHOCLASE, very large crystals, with specimens of asso- 
ciated minerals from veins of coarse pegmatite on the 
north shore of Long Island Sound. 
Collected (1895) and exhibited by Prof. J. F. Kemp, 
Columbia University. 
TourMALINE. Bethel, Conn. A very large crystal. Ex- 
hibited by Prof. E. S. Dana, Yale University. 
Frporow UnIvEerRSAL MicroscoPpE STAGE, combined with 
the KLEIN ‘‘ UNIVERSAL-DREHAPPARAT ;” made by R. 
Fuess in Berlin after the plans of Prof. E. von Fedorow, 
of Moscow, and Prof. C. Klein, of Berlin. 
This apparatus, if placed on the stage of a polarizing 
microscope, allows the object, whether a thin section of 
a rock or mineral or a small crystal, to be placed at al- 
most any angle to the axis of the microscope, for by 
means of the two axes of revolution, in addition to the 
usual horizontal revolution of the stage of the microscope 
about the axis of the instrument, we are able to revolve 
the object about three axes at right angles to each other, 
and hence bring almost any direction in it parallel to the 
axis of the microscope, subject of course to the necessary 
limitations to the extent of the motion which the condi- 
