Page:Russian Realities and Problems - ed. James Duff (1917).djvu/194

 Observatory at Pulkovo in 1839, by Struve and his pupils. In course of time Bredihin, a former student of the University of Moscow, became director of this institution: he was well known for spectroscopic and other investigations on the comets and shooting stars; and the recent Director, Backlund, very highly appreciated in scientific circles, was himself aided by one of the assistants of Bredihin, the astrophysicist Byelopolsky.

These various branches of knowledge received some new applications in the study of geodesy, which particularly concerned Russia. The materials collected by Delisle and Kirilov, an amateur of Russian cartography, proved to be of some use even for the Atlas of 1745 ; the determinations and measurements made by Vishnijevsky, Struve and others before the foundation of the Observatory of Pulkovo, and the subsequent triangulations of the military topographical department, made by Stebnitsky, Tillo and others, contributed largely to the improvement of Russian maps: the best of these were executed by Stryelbitsky and his assistants.

Mathematical treatment could not, however, overcome all the difficulties which such an investigation presented in respect to complicated natural phenomena, particularly in the early days of Russian science. In