PROCEEDINGS OF THE ACADEMY AND AFFILIATED 



SOCIETIES 



WASHINGTON ACADEMY OF SCIENCES 



139TH MEETING 



The 139th meeting of the Academy was held in the Assembly Hall 

 of the Cosmos Club at 8.15 p.m., on Thursday, January 29, 1920; 

 President Alsberg presided. Dr. C. G. Abbot, Director of the 

 Astrophysical Observe atory, Smithsonian Institution, delivered an illus- 

 trated lecture on The use of solar radiation measurements in weather 

 forecasting in Argentina. The substance of the lecture is published in 

 this number of the Journal. 



Discussion. Professor C. F. Marvin, Chief of the Weather Bureau, 

 presented the following discussion : 



We must all admire and commend in the highest terms the persistent 

 and conscientious effort which Mr. Clayton has expended in carrying 

 forward for several years the tedious studies he has executed to ex- 

 hibit a correlation between daily and short-period fluctuations in ob- 

 served values of intensities of solar radiation and terrestrial tempera- 

 ture and other phenomena of weather. I wish especially to commend 

 in the highest terms the splendid work done by the Astrophysical 

 Observatory of the Smithsonian Institution under the able director- 

 ship of Dr. Abbot in perfecting methods and apparatus for the exact 

 measurement of solar radiation intensities, and in securing almost 

 daily values thereof. I do not know of any one element of observation 

 possessing greater fundamental importance to theoretical meteorology 

 than that of the intensity of solar radiation. Dr. Abbot's investiga- 

 tions command our unqualified appreciation and his work deserves to 

 be encouraged and extended as far as possible, purely on the basis of 

 the great value of the work itself. 



With reference to Air. Clayton's findings, I feel compelled to say I 

 cannot at present join with Dr. Abbot in his seeming enthusiastic 

 acceptance of the former's views. Mr. Clayton's latest paper has been 

 in my hands only a few days and has received but a very hasty exam- 

 ination. The hesitation I feel in accepting its conclusions is based on 

 certain general principles and convictions and may be overcome by a 

 critical and detailed study which such a paper must receive before its 

 merits or faults are fully disclosed. 



It is obviously impossible, in the few minutes available to me this 

 evening, to attempt to discuss any details of this highly complex and 

 intricate problem — I must confine myself to a very few fundamental 

 considerations and convictions. 



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