DORP AT AND POULKOVA. 377 



tlie Revision of tlie nortlieni heavens for all stars to the eighth magnitude, by Otto 

 Strave, in 1841-42, and the resulting catalogue of 514 new multiple stars, (St. 

 Petersburg, 1843;) the publication of Weisse's Reduction of BesseVs Zones, 

 (St. Petersbin-g, 1846 ;) of Dollen's Reduction of the Kouigsberg Declinations, 

 (St. Petersburg, 1849;) of Otto Strnve's Revised Catalogue of Double Stars 

 discovered at Poulkova, (St. Petersburg, 1850 ;) of Fedorenko's Reduction of 

 Lalande's Circumpolar Stars, (St. I'etersburg, 1854.) 



And to these wo must ad<l certain studies which are of great interest and 

 value from their bearing upon subjects of investigation that still elude our secure 

 grasp: Struve's Etudes d'Astronomie Stellaire, (St. Petersburg, 1848;) Peters's 

 Recherches sur la Parallaxe des etoiles fixes, (St. Petersburg, 1848 ;) Otto 

 Struve's Investigations into the ParalLaxes of 1830, Groombridge, (1850;) of 

 a LjTse, (1852;) of a Lyrse and 61 a Cygni, (1854;) Dollen's Criticism, St.) 

 Petersburg, 1853;) of Wichman's Parallax of 1830, Groombridge. 



Nor had the attention of the observatory been drawn from the bodies of the 

 solar system. In 1843 was published the elaborate memoir on the orbit of the 

 comet of lS39-'40 by Peters and Otto Struve ; in 1849 and 1850 the Observa- 

 tions of the Satellite of Neptune and Deduction of Neptune's Mass, by Otto and 

 August Struve; in 1852 Otto Struve's Observations of the Rings of Satixrn, and 

 in 1854 his Observations of Biela's Comet ; finally, in 1853, by Struve and 

 LiapounoflP, the Reduction of the Dorpat Observations of the Sun, Moon and 

 Planets. 



In practical astronomy the publication (1845) of the Description of the Cen- 

 tral Observatory had formed a memorable epoch, and the annual Russian edition 

 of the English Nautical Almanac brought that indispensable work to the conve- 

 nient use of the Russian officers. 



In geodesy the expedition of 1838-41, suggested and planned by Strui-e for 

 the determination of the difference of level between the Black and Caspian Seas, 

 (St. Petersl)urg, 1849,) had added much to the geography of that little known 

 portion of what was then the Russian frontier, and gave occasion to Struve to 

 make a very valuable contribution to our knowledge of terrestrial refraction; 

 the longitude expeditions to Altona and Greenwich in 1843-44, and the annual 

 geogi-aphic expeditions into the interior of Russia, and especially the steadily 

 progressing measurement of a grand meridional arc of 25 degrees of latitude, 

 were (jontinual reminders of the vastness and national importance of the works 

 undei'^akeu by the Central Observatory, and by those who were the co-workers 

 of its amiable director. 



Nor was the rapid progress of astronomy in Russia unnoticed by the astrono- 

 niers of foreign countries. Already in 1840 had the kindly Schumacher cele- 

 brated the 2.5th year of their friendship by a personal visit to Struve, and had 

 borne testiuiony to the advance that ha<l been realized by the establishment of so 

 imperial an institution; and in 1842 the King of Prussia, on beholding the 

 splendor of I^oulkova, had the condescension to promise that Bessel and 

 Argelander should certainly have opportunities given them to visit this " Eldo- 

 rado." It was, however, not until 1853 that the latter was able to leave 

 Bonn and gratify his long-repressed desire, and the life-long friend of Struve 

 could but say that the half had not been told him. Even from America came 

 tiibutes to the fame of Poulkova; first, when in 1848 it Avas visited by our emi- 

 nent countryman, whose impressions as i)uhlished in the North American Review 

 (1849) created among us a wide-spread interest in Struve and his Central Obser- 

 vator}^ ; and again when visited in 1851 by the late director of the Harvard Col- 

 lege Observatory, to whom, when still at a distance from St. Petersburg, Struve 

 sent a message of welcome. 



It was in 1857, when the high rank of Poulkova in matters pertaining to 

 astronomy and geodesy had thus been so forcibly demonstrated at hoiue, and so 

 widely acknowledged abroad, that the necessity became imperative for a change 



