ARTHUR SEARLE. 



511 



the meridian circle observations for the Zone Catalogue of 8337 Stars 

 between 9° 50' and 14° 10' of South Declination in 1855 for the Epoch 

 1900.0. The results fill Volumes 62, 65, 66, 67, and 70 of the Harvard 

 Annals. The Catalogue itself, contained in Volume 67, was published 

 in cooperation with the Astronomische Gesellschaft. The reduction 

 and publication of these observations with the superintendence of 

 other computers consumed most of his time and energy until he retired 

 in 1912. ^Yith his customary modesty, he regarded this not as a 

 personal undertaking but as a large piece of routine work. Neverthe- 

 less, the various investigations related to meridian circle observations, 

 which he undertook in the course of the work, show his skill and in- 

 genuity in meeting such problems. They are indicated in the Intro- 

 duction to the Catalogue just mentioned. Reference may be made 

 here to " Results of Accessory Series of Observations made with the 

 Meridian Circle," and " Comparison of Results obtained with differ- 

 ent Forms of Apparatus in Meridian Observations," in the Annals of 

 Harvard College Observatory, Volumes, 33, No. 11, and 41, No. 7. 

 In 1908 he published in the Harvard Annals, Volume 60, No. 1, 

 "Geometrical Methods in the Theory of Combining Observations." 

 In the Annals, Volume 29, No. 6 are his observations of ^ Persei, and 

 surrounding comparison stars. 



Besides various articles in periodicals, he published "Outlines of 

 Astronomy" in 1874, followed by a second edition in 1875. In 1910 

 his "Essays I-XXX" appeared, which, among other topics, discussed 

 " Space and Time," interesting in the light of the theory of relativity. 



Professor Searle became a Fellow of the Academy in 1877, at the 

 same time with Professor Charles R. Cross, who recently died. His 

 scientific papers presented to the Academy, and not already mentioned 

 are in the Proceedings, Volumes 19, 24, and 55. The last paper " Orbits 

 Resulting from Assumed Laws of Motion" was a result of an extensive 

 investigation begun in 1882, forming an important part of a treatise 

 which he had practically completed at the time of his death. Reading 

 this paper on the balanced effect of "inward" and "outward" forces 

 on a moving body, one is carried back to the initial physical experi- 

 ment, which he performed in his childhood with the help of his aunt's 

 spinning wheel. 



He was very much of a mathematician, and when any question of 

 the sort arose he was consulted. The results will be found in various 



