CONTENTS 



Original Papers 



Page 



Geophysics. — Volcanic dust as a factor in the production of climatic 

 changes. W. J. Humphreys 365 



Physics. — Melting points of the refractory elements, I. Elements of atomic 

 weight from 48 to 59. G. K. Burgess and R. G. Waltenberg 371 



Proceedings 

 The Botanical Society of Washington 379 



