CONTENTS 
Pagt 
Petroi^ogy. — On ChondruivES and Chondritic Structure in Meteorites 
By George P. Merrill 449 
Physics. — The Verticai. Interferometer By A. A. Michelson 473 
Physics. — On the Appwcation of Interference Methods to Astronomicai, 
Measurements By A. A. Michelson 474 
Physics. — Modification of the Revoi<ving Mirror Method for Measuring 
THE VE1.0CITY OF Light By A, A. Michelson 476 
Physics. — On the K Series of X-Rays 
By William Duane and Wilhelm Stenstrom . . 477 
Astronomy. — Studies of Magnitude in Star Ci^usters, XII. Summary of a 
Photometric Investigation of the Gi.obui.ar System Messier 3 
By Harold Shapley and Helen N. Davis . . 486 
ANTHROPOI.OGY. — ^The INF1.UENCE OF Environment upon Development 
By Franz Boas 489 
Physics. — The Possibii^ities of the Rocket in Weather Forecasting 
By Robert H. Goddard 493 
Physics. — Note on a Pneumatic Method of Measuring Variations of the 
ACCE1.ERAT10N OF Gravity By Carl Barus 495 
Physics. — ^Note on Torsionai. Measurement of Variations of the Accelera- 
tion OF Gravity by Interference Methods By Carl Barus 498 
Botany. — The Genus Botrychium and It's Relationships. .By D. H. Campbell 502 
