EEPORT OF THE SECRETARY 5 



With the completion of these projects, the Zoo will have four large 

 modern exhibition buildings, and tlie new construction constitutes the 

 greatest improvement in the history of the Park. Assigimient of 

 P. W. A. labor also enabled the Park to carry out a considerable 

 number of lesser improvements, including work on roads, grounds, 

 and buildings. Accessions of animals numbered 786. Losses by 

 death and otherwise totalled 765, leaving the collection at the close 

 of the year at 2,191 animals, representing 675 different species. Vis- 

 itors numbered 2,235,850, including groups from 579 schools and 

 organizations from 20 States and the District of Columbia. 



Astrophysical Observatory. — ]\Ieasurements of the solar constant of 

 radiation have been continued on every possible day at the three 

 Smithsonian stations at Table Mountain, Calif., Montezuma, Chile, 

 and Mount St. Katherine, Egypt. The irregularity of the results at 

 Table Mountain led to the development of a criterion for distinguish- 

 ing unfavorable sky conditions, which will provide a new increase in 

 the accuracy of measurement of the solar variability. Two papers 

 published by Dr. Abbot appear to prove that the short-interval 

 changes of solar radiation are of major influence on the weather for 

 the ensuing 2 weeks or more. To test the use of this relationship in 

 weather forecasting, seven additional observmg stations are required. 

 An amendment to the Urgent Deficiency Act providing the necessary 

 funds was passed by the Senate, but was rejected in conference with 

 the House. Preliminary studies were begun of the possibility of 

 automatic determination of solar variability from sounding balloons. 



Division of Radiation and Organisms. — The Division's investiga- 

 tions comprised the following : Continuation of work on the depend- 

 ence of carbon dioxide assimilation in wheat upon the wave length 

 of radiation ; experiments on the effects of ultraviolet rays on algae ; 

 experiments on the effects of light of different wave lengths on 

 growth of tomatoes; development of an extremely sensitive and 

 quick-acting spectroscopic method for measuring carbon dioxide con- 

 centration; study of the dependence of photosynthesis in wheat on 

 time factors; and the development of a higlily sensitive thermo- 

 couple of great ruggedness. 



THE ESTABLISHMENT 



The Smithsonian Institution was created by act of Congress in 

 1846, according to the terms of the will of James Smithson, of Eng- 

 land, who in 1826 bequeathed his property to the United States of 

 America "to found at Washington, under the name of the Smith- 

 sonian Institution, an establishment for the increase and diffusion of 

 knowledge among men," In receiving the property and accepting 

 the trust. Congress determined that the Federal Government was 

 without authority to administer the trust directly, and, therefore, 



