REPORT OF THE PRESIDENT, I912. 9 



addition to the zonal catalogues and with every other advance in stellar as 

 distinguished from planetary astronomy. It has long been known that the 

 so-called "fixed stars" are not fixed, but it is only recently that something 

 like order has begun to be discovered in the chaos of residual motions hith- 

 erto attributed to the stars. Happily for the earlier progress of astronomy, 

 by reason of the great distances asunder of these bodies, their apparent mo- 

 tions are in general small — so small, in fact, that they have been frequently 

 confounded with the small but inevitable errors of observation. Moreover, 

 these "proper motions" as measured by the astronomer are entangled not 

 only with the motions of his observatory in its journey on the earth around 

 the sun, but also with the motion of the entire solar system in space. 



It was in the study of these problems of stellar and solar motion that Boss 

 was engaged, independently and almost single-handed, when the Institution 

 came to his aid, first by minor grants made during the years 1904-1906 and 

 then by the establishment of the Department of Meridian Astrometry at the 

 beginning of the year 1906. He had set for himself the stupendous task of 

 producing a catalogue of the highest precision of all stars in both hemi- 

 spheres, from the brightest to the seventh magnitude inclusive, together with 

 fainter stars of suspected or known proper-motion — a total of about 26,000 

 stars. It was for this work that he established, under the auspices of the 

 Institution, a temporary observatory at San Luis, Argentina, in 1909. As a 

 contribution to this work also there was published by the Institution, early 

 in 1910, a "Preliminary General Catalogue of 6188 Stars for the Epoch 1900, 

 including those visible to the naked eye and other well-determined Stars." 

 This catalogue immediately took first place among such publications, and the 

 demand for it has been so great that the edition is already nearly exhausted. 

 The positional measurements at the observatory in Argentina were com- 

 pleted early in 191 1 and the staff of Professor Boss's department has since 

 been, and is still, engaged on the computations essential to the completion of 

 the comprehensive catalogue just referred to. Fortunately this work is in a 

 favorably forward state, and the plans for its execution are so well laid that 

 it may be completed in due time in accordance with the exacting ideals of its 

 author. 



It is a happy circumstance that before his death Professor Boss visualized 

 in large degree the rich harvest of results that must come to sidereal as- 

 tronomy with the completion of his grand catalogue. From some prelimi- 

 nary papers which he published on the motion of the sun, on the common 

 motion of the stars in the Taurus group, and especially on the systematic 

 motions of the stars and their relations to stellar types, it is evident that he 

 saw plainly how the older branch of positional astronomy, fundamental for 

 geography, geodesy, navigation, and the reckoning of the lapse of time, may 

 come to supplement and to extend the newer branch called astrophysics, 

 which seeks to learn more of the origins, the interrelations, and the destinies 

 of the heavenly bodies. Thus, while he did not live to see the extraordinary 

 task he set for himself completed, he realized a kind of good fortune which 



