CONTENTS 



Original Papers 



Page 



Astrophysics. — ^The variation of the sun. C. G. Abbot, F. E. Fowle, and 

 L. B. Aldrich ;..... 309 



Physics. — ^The melting points of some refractory oxides. C. W. Kanolt... 315 

 New modified thermoelectric methods in calorimetry. Walter P.White 319 

 On the absorption of light in heterogeneous media. P. G. Nutting... 322 



Radiotelegraphy. — Difference in strength of day and night signals in radio- 

 telegraphy. L. W. Austin 326 



Metallography. — Preliminary note on the critical ranges, A3 and A2, of 

 pure iron. G. K. Burgess and J. J. Crowe 329 



Abstracts 



Meteorology. 333 



Climatology 334 



Chemistry 334 



Paleontology 336 



Zoology 336 



Bacteriology .". 337 



Proceedings 



The Washington Academy of Sciences : . 339 



The Chemical Society 340 



The Geological Society of Washington 343 



