APPENDIX 8 

 Report on the Astrophysical Observatory 



Sir : I have the honor to submit the following report on the opera- 

 tions of the Astrophysical Observatory for the fiscal year ended 

 June 30, 1952 : 



The work of the Astrophysical Observatory is divided between 

 two units: the division of astrophysical research, for the study of 

 solar radiation problems, and the division of radiation and organisms, 

 established "to undertake those investigations dealing with radiation 

 bearing directly or indirectly upon biological problems." In addi- 

 tion to their regular programs, both divisions are conducting coopera- 

 tive projects with other Government agencies. The division of astro- 

 physical research at its Chilean field station maintains certain seismo- 

 graphic records for the Coast and Geodetic Survey and also records 

 solar radiation received upon exposed fabrics, under contract with the 

 Office of the Quartermaster General. The division of radiation and 

 organisms has in progress special experiments for the Atomic Energy 

 Commission and for the Biological Department, Chemical Corps, 

 Camp Detrick, Md. 



During the year the metal and glasswork shops serving both divi- 

 sions of the Observatory were materially improved by the installation 

 of modern lighting equipment, re-arrangement of the machines, re- 

 painting, reflooring, and the addition of specially built cabinets for 

 storing raw materials. The instrument makers now operate with 

 less eye strain, more convenience, and greater safety. 



In August 1951 the Director of the Observatory attended meetings 

 of the Sub-Commission on Actinometry of the World Meteorological 

 Organization held at Brussels, Belgium. In the resolutions adopted 

 by the Sub-Commission, the Smithsonian silver-disk pyrheliometer, 

 designed and developed by Dr. C. G. Abbot, is recommended as an 

 instrument for the measurement of direct solar radiation. 



DIVISION OF ASTROPHYSICAL RESEARCH 



The question of establishing a field station in the Clark Mountain 

 (Calif.) region, mentioned in previous reports, is still undetermined. 



W. H. Hoover, chief of the division, spent July and part of August 

 at the Table Mountain (Calif.) field station, directing the work pro- 

 gram and testing several new devices. 



130 



