APPENDIX 8 

 REPORT ON THE ASTROPHYSICAL OBSERVATORY 



Sir : I have the honor to submit the following report on the activities 

 of the Astrophysical Observatory for the fiscal year ended June 30, 

 1940: 



These operations are conducted on funds received in part from the 

 appropriation by Congress, amounting for the fiscal year 1940 to 

 $32,070, and in part from private sources. The latter included parts 

 of the income from the Hodgkins and the Arthur funds, and grants 

 for specified objects from John A. Roebling. These private sources 

 contributed altogether $19,000 during the fiscal year. 



At Washington, the work is carried on in two old frame buildings 

 south of the Smithsonian Building. There are three mountain stations 

 located in New Mexico, California, and Chile. At these stations, 

 chosen for low winds, high altitude, and extreme cloudlessness, without 

 much regard for living conditions, the principal apparatus is housed 

 within a horizontal tunnel to secure fairly constant temperature condi- 

 tions. Small dwellings, computing rooms, and garages complete the 

 establishments, which are designed to accommodate only a field direc- 

 tor, one assistant, and their families. During the fiscal year a rein- 

 forced cement block dwelling has been under erection at the station 

 at Montezuma, Chile, but is not yet fully completed, so that the incom- 

 modious frame dwelling there is still occupied. 



WORK AT WASHINGTON 



Messrs. Aldrich and Hoover, with a force of regular and special 

 computers, some of whom were furnished by W. P. A., continued to 

 work on the complete revision of all results on the solar constant of 

 radiation from all stations and from 1923 to the present time. Many 

 small inconsistencies revealed themselves between results of a single 

 station in different years, and between the results of the different sta- 

 tions in the same year. Each of these inconsistencies was a problem 

 in itself, requiring extensive study, and in some cases extensive remeas- 

 urements of photographic records. Consequently, progress was slow 

 in preparing final tables of daily, decadal, and monthly mean values 

 of the solar constant, based on the evidence of all observations. It had 

 been hoped that these results would be ready to assemble and publish 

 early in the calendar year 1940. But at the end of June there still 

 remained several very troublesome questions to be resolved, so that 

 several months more of study seemed indicated. 



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