EEPORT OF THE SBGBETARY. 7 



Aldrich together worked on the problem of searchlights for Army 

 use, and, after numerous experiments, they were able to improve the 

 existing searchlights, both by diminution of size and increase in light- 

 ing power. The new form of searchlight was constructed and used in 

 France several months before the close of hostilities. 



At the time of the signing of the arjiiistice several valuable devices 

 were being perfected by Dr. Abbot and the observatory staff, among 

 them a recoilless gun devised by Dr. E,. H. Goddard, of Clark College, 

 which was a development of work being done by him for the Insti- 

 tution on a multiple-charge rocket intended to reach great heights for 

 meteorological observations; an instrument for determining .geo- 

 graphical positions from an airplane or a ship at sea without refer- 

 ence to landmarks, whether celestial or terrestrial ; and a 7-otatiiig 

 projectile constructed on the turbine principle to be fired from a 

 smoothbore gun, which would have been specially valuable for use in 

 trench mortars. 



On December 16, 1918, Dr. C. G. Abbot, Director of the Astrophysi- 

 cal Observatory, was appointed assistant secretary of the Institution 

 to fill the vacancy caused by the death of Dr. F. W. True some years 

 ago. In addition to his administrative duties in connection with the 

 Institution. Dr, Abbot will be in charge of the Smithsonian Library, 

 the International Exchange Service, and the Astrophysical Obser- 

 vatory. 



The work of the T»J^ational Research Council, of which your secre- 

 tary was first vice chairman, was continued under the war organi- 

 zation during the first part of the year. After the signing of 

 the armistice every effort was concentrated on the organization of 

 the council upon a peace basis, and this was accomplished very suc- 

 cessfully before the close of the year under a definite plan in accord- 

 ance with an Executive order from the President of the United 

 States requesting the National Academy of Sciences to perpetuate 

 the National Research Council. 



The secretary of the Institution was also chairman of the executive 

 committee of the national advisory committee for aeronautics, which 

 performed work of great value to the Government on airplane pro- 

 duction and improvements. 



An important peace-time event was the organizing just before the 

 close of the year of an extensive exploring expedition to the heart 

 of Africa. The material collected will come to the Institution to 

 be used for purposes of comparison in working up the results of 

 various expeditions to the Dark Continent by Col. Roosevelt, Paul 

 Rainey, and others. 



Bequests. — An important bequest was made to the Institution dur- 

 ing the year by Mrs. Virginia Purdy Bacon, of New York, which 

 will do much toward extending our knowledge of the fauna of the 



