772 RECENT PUBLICATIONS 
WricHtT, FRED. EuGENE. A Telemeter with Micrometer Screw Adjustment. 
And a Device to Aid in the Explanation of Interference Phenomena. 
[The American Journal of Science, Vol. XXVI, December, 1908.] 
——. On Three Contact Minerals from Velardefia, Durango, Mexico 
(Gehlenite, Spurrite, and Hellebrandite). [The American Journal of 
Science, Vol. XXVI, December, 1908.] 
