126 ANNUAL EEPOET SMITHSONIAN INSTITUTION, 1912. 



He offers to pay all expenses, except salary, of a representative of the 

 Institution, who will make natural-history collections, the mammals 

 to be deposited in the National Museum. Dr. Lyman is in corre- 

 spondence with the American embassy at St. Petersburg as to the 

 probable safety of such a journey, and will start at an early date if 

 indications are favorable. It is expected that Mr. Ned Hollister, a 

 Museum naturalist, will be designated to accompany Dr. Lyman. 



" Smithsonian Algerian expedition. — For several years, as has been 

 stated in the secretary's reports, the Astrophysical Observatory of the 

 Institution has been engaged in a study of the solar constant of 

 radiation. The work has been conducted under the immediate super- 

 vision of Mr. Charles G. Abbot, director of the Observatory, whose 

 studies at Washington, D. C, and Mount Wilson and Mount "Wliit- 

 ney, Cal., indicated that the sun was probably a variable star, its 

 radiations fluctuating from 2 per cent to 5 per cent during irregular 

 periods of from 5 to 10 days' duration. This lack of constancy was 

 so important that it seemed necessary to test it further by means of 

 simultaneous observations held at Mount Wilson and some other high- 

 altitude station remote from that point where an equally cloudless 

 atmosphere existed. 



" Mr. AUbot selected Algeria for these additional observations, and 

 in July last established a station at Bassour, where until November 

 he carried on the work with the assistance of Prof. Frank P. Brackett, 

 of Pomona College, California. Similar observations were made at 

 the same time by Mr. L. B. Aldrich at the station on Mount Wilson, 

 which is separated from Bassour by a distance equal to about one- 

 third of the earth's circumference. 



" Mr. Abbot, though hampered by some unexpectedly cloudy 

 weather, made successful observations on about thirty days, and while 

 much computing and comparing remains to be done before the final 

 results can be stated, a strong hope is entertained that they will go 

 a long ways toward definitely solving tlie question as to the varia- 

 bility of the sun. 



" The practical bearing of this work is impoilant. Weather fore- 

 casting is not as yet an exact science, being in fact, except in the 

 matter of pronounced storms and hot and cold waves, but little more 

 than refined guesswork. If radiation proves to be a strongly con- 

 trolling factor, forecasting would be much simplified. 



NATIONAL MUSEUM. 



''''Freer collection. — Preparations are now in progress looking to 

 the temporary exhibition, beginning in April, 1912, of a selection of 

 objects from the Charles L. Freer collection of American and oriental 

 art. One of the large halls in the new Museum building will be 

 used for the purpose, and during a period of about two months the 



