120 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1947 



of the site to the custody of the Forest Service. The equipment was 

 sent to Miami, Fla., and stored pending the completion of a building 

 suitable for temporary solar observations at this sea -level location. 



In further development of their studies of the causes of tent dete- 

 rioration, the Quartermaster Department decided to extend the Camp 

 Lee work to include measurements and exposures at a wet, sea-level 

 station and also at a dry, high-altitude station. Fortunately, in Miami, 

 Fla., the General Motors Corp. maintains a test field for the exposure 

 and testing of various materials. At the suggestion of Dr. S. J. 

 Kennedy, of the Military Planning Division, Office of the Quarter- 

 master General, a cooperative program was arranged between the 

 General Motors Corp., the Quartermaster Department, and the Smith- 

 sonian Institution. General Motors generously undertook to build a 

 special observing shelter at their test field, to house our spectrobolo- 

 metric equipment formerly in operation at Tyrone, N. Mex. This 

 building, a most satisfactory, well-insulated structure of cement brick, 

 was completed in April 1947. On May 1 F. A. Greeley, recently 

 director at our Montezuma, Chile, station, took charge of the installa- 

 tion of our equipment. Spectrobolometric observations are planned 

 for a period of 1 year. 



During the war years our field stations were unavoidably under- 

 manned. It is therefore a satisfaction to state that each of the stations 

 now has two competent observers, as in prewar days. 



During the fiscal year, a generous gift to further the work of the 

 Division was received from John A. Roebling. The staff of the 

 Observatory is sincerely grateful to Mr. Roebling, and to Dr. Abbot 

 through whose kindly interest the gift was received. 



(2) DIVISION or RADIATION AND ORGANISMS 



(Report prepared by Earl S. Johnston, Chief of the Division) 



General. — Members of the Division were consulted as usual by out- 

 side individuals and organizations regarding problems arising in the 

 field of radiation, its measurement and its effect on living matter. 

 Individual members also participated actively in the affairs of national 

 and local scientific organizations. 



Research. — During the year the research of the Division of Radiation 

 and Organisms was concentrated under two projects: (1) Photosyn- 

 thesis, and (2) plant growth and development as influenced by light. 



(1) Photosynthesis. — The purpose of this project is to determine 

 the role of light, especially the wave-length effects, on the fixation of 

 carbon by green plants. Included in this project are studies (a) to 

 determine a more complete photosynthesis-action spectrum by use of 

 the special spectrographic method for the determination of carbon 



