28 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 76 



especially plans for construction of buildings, cages, enclosures, care 

 of wild animals, etc., and cooperates constantly with zoological socie- 

 ties and similar public and private organizations in various activities. 



The Astrophysical Observatory 



The present work of the Astrophysical Observatory is of special 

 interest to meteorologists, for since the temperature and other weather 

 conditions of the earth depend upon the sun, the variations of the 

 sun may probably produce predictable changes in weather conditions. 



For several years past, the monthly records of solar radiation have 

 been furnished to the United States Weather Bureau for publication 

 in its Monthly Weather Review. Since December, 1919, telegraphic 

 reports of the daily observations at the Chile observing station have 

 been sent to the Weather Service of Argentina, and have been em- 

 ployed there for forecasting purposes. The Argentine Government, 

 at present, publishes weekly a forecast, one week in advance, based 

 upon the Chilean observations of the Smithsonian Institution. 



Frequent requests for information in regard to matters of solar 

 radiation, physics, and astronomy are answered by the Astrophysical 

 Observatory. (See also under Hodgkins Fund, p. 8.) 



International Exchanges 



Perhaps the most far-reaching of the forms of cooperation in 

 which the Smithsonian has taken a leading part is that universally 

 known under the title of the Smithsonian International Exchange 

 Service. 



This system was established early in the history of the Institution, 

 at first purely as a channel for the interchange of scientific publica- 

 tions and specimens, and therefore as a direct means for " the diffu- 

 sion of knowledge," a means which has proved to be a great benefit 

 to the scientific institutions of the world, and incidentally to Congress, 

 in building up the unequaled collection of works of reference de- 

 posited in its library. 



In order to convey an idea of the present magnitude and charac- 

 ter of the exchange transactions, it may be stated that during the 

 year 1889, 17,218 packages were mailed to correspondents in the 

 United States, and 693 boxes, containing 58,035 packages, were 

 shipped to agents abroad for distribution to correspondents in nearly 

 every civilized nation of the earth. The total number of packages 

 received was 75,966, of which 34,996, or nearly one-half, were gov- 

 ernmental exchanges. In 1922, the number of packages handled had 



