PHYSICS. 407 



regards their absorption and fluorescence, make this investigation 

 especially interesting. 



Mr. H. E. Howe has completed the preliminary work in an investiga- 

 tion of the absorption in the ultra violet of solutions of a number of 

 organic compounds of unusual purity. It is hoped that the method 

 used will give more accurate quantitative results than have hitherto 

 been obtained. 



Professor R. C. Gibbs has been planning and testing apparatus for 

 the study of the absorption spectra of pure organic compounds in 

 various solvents. It is intended to extend the measurements through- 

 out as wide a range of the spectrum as possible, including both the 

 infra-red and ultra-violet regions. This investigation is being under- 

 taken in collaboration with Professor W. R. Orndorff. 



Nipher, Francis E., Washington University, St. Louis, Missouri. Determina- 

 tion of magnetic effects of an explosion of dynamite. 



The work done in the summer of 1914 at Hessel, Michigan, estab- 

 lished to my full satisfaction the magnetic disturbance due to "out- 

 bursts" of flame from burning powder (blasting powder) and from 

 dynamite explosions. This is a local disturbance in the earth's mag- 

 netic field. The effect of the fog-horn of a steamer about half a mile 

 distant was also observed on clear days, not on cloudy days. Verbal 

 accounts of this work have been given to the Academy of Science of 

 St. Louis. The secretary has written brief abstracts of my informal 

 reports to Science. I also detected what appeared to be a magnetic 

 field around a column of exploding dynamite. The direction of de- 

 flection was reversed when the direction of explosion was reversed. I 

 do not regard this result as conclusively established. This would be a. 

 special case of Rowland's convection current. 



