4 ANNUAL REPORT SMITHSONIAN INSTITUTION, 19 3 5 



at the Century of Progress Exposition. Extensive reports were pub- 

 lished on the archeology of Nebraska and of the Bay Islands of 

 Spanish Honduras. 



International Exchanges. — In the official exchange with other 

 countries of governmental and scientific documents, the exchange 

 service handled during the year a total of 654,131 packages, weigh- 

 ing 560,381 pounds. There are now 111 full and partial sets of 

 governmental documents and 102 copies of the daily issue of the 

 Congressional Record sent to foreign depositories. 



National Zoological Park. — Accessions to the collection during the 

 year numbered 627, and removals through various causes totaled 

 695, leaving the collections at the close of the year at 2,170 animals, 

 representing 665 different species of mammals, birds, reptiles, and 

 other forms. The number of visitors was 2,046,149, including groups 

 from 394 schools in 20 States and the District of Columbia. An allot- 

 ment of $680,000 was made on January 26, 1935, by the Public Works 

 Administration for the construction of a small mammal house, a 

 pachyderm house, an addition to the bird house, and mechanical 

 shops, buildings that have been urgently needed for many years. 

 Work was immediately started on the plans and specifications in the 

 office of the Supervising Architect, with Edwin H. Clarke as con- 

 sulting architect. Much work was also done on the buildings and 

 grounds with labor and materials supplied by the Emergency Works 

 Administration. The greatest need of the Zoo is for more liberal 

 appropriations for the purchase of specimens. 



Astrophysical Observatory. — Regular observations of the solar 

 constant of radiation have been continued daily at the three solar 

 observing stations at Table Mountain, Calif.; Montezuma, Chile; 

 and Mount St. Katherine, Egypt. The observations from Mount 

 St. Katherine have been reduced at the central station at Washing- 

 ton under the direction of the assistant director, L. B. Aldrich, 

 assisted by a special staff of computers made available under a grant 

 from John A. Roebling. The results indicate that this station, 

 established in 1934, will prove to be one of high excellence. Analysis 

 of solar variation since 1920 has revealed 12 periodicities, all aliquot 

 parts of 23 years. These periodicities are also found in temperature 

 and precipitation records for six terrestrial stations for the past cen- 

 tury, and the 23-year cycle is found in the levels of lakes and streams, 

 the widths of tree-rings, the catches of ocean fish, varves of Pleisto- 

 cene and Eocene geologic age, and other phenomena depending on 

 weather. Forecasts of temperature and precipitation for 1934, 1935, 

 and 1936 for over 30 stations in the United States have been made, 

 and satisfactory agreement between forecasts and the events have 

 been found for two-thirds of the stations during 1934. 



