376 DORPAT AND POULKOVA. 



utilitaiian, and lie found in this opening field of usefulness tlie proper opportu- 

 nity for i'ully reimbursing' the government for the great expenses attendant upon 

 the maintenance of the observatory. But the diversion of the small astronomi- 

 cal force of the obsen^atory from scientific investigations to practical applications, 

 from study to. teaching, in the course of time threatened to seriously interfere 

 with the attainment of the first and important aim of the institution. So long as 

 the extended labors of the Central Observator}' were borne by five persons, (the 

 director and four adjunct astronomers,) so long must the general progress of the 

 observatory work be painfully slow, and the urgent need for making provision 

 for further assistance, especially in the matter of reductions, became daily more 

 pressing. 



It was in 18-36 that the observatory was called upon to lament the death of its 

 founder and friend, Nicholas I, whose name it has since borne, but the imperial 

 successor, the present Alexander II, failed not to provide bountifully for the 

 proper maintenance of an institution so useful to the state and so honorable as a 

 testimonial to the wise munificence of his father. Within a 3^ear the annual 

 income of the observatory was doubled, and the friendly dispositions of the 

 department of war, of the navy, and of public instruction, were abundantly mani- 

 fested by their respective ministers. Not only were the hitherto meagTO salaries 

 of the four astronomers now properly increased, but by the addition of two 

 adjunct astronomers and two permanent computers, as well as by the ability to 

 engage temporary assistance, the effective working force of the observatory was 

 nearly doubled, and the immediate danger that abstract science would be entirely 

 supplanted by its practical applications was averted. 



The change in tlie relations of the Central Observatory to the various depart- 

 ments of the civil government which was brought about diu'iug the succeeding 

 five years was the inevitable consequence of its active usefulness during the first 

 eighteen years of its history. We will briefly consider the work done at Poul- 

 kova during this period, though we can scarcely do more than enumerate the 

 titles of the most important of the one hundred and fifteen memoirs published by 

 its astronomers previous to 1858. 



The long series of Dorpat meridian observations extending from 1822 to 1843, 

 already publislied in successive volumes and in separate treatises, required, in 

 Struve's opiifion, a final revision as regards their reductions, and a publication as 

 one work, inasmuch as they had been conducted upon one plan and formc^ con- 

 secutive portions of a symmetrical whole. The original Dorpat records of ooser- 

 vation are still preserved at Poulkova in accordance with the laws regarding 

 that observatory, and from them were compiled the resulting catalogue • Stel- 

 larum lixarum positiones mediie; auctore F. G. W. Struve, Petro})oli, 18.52. 

 The following works must be considered as preliminary to this invaluable cata- 

 logue : The Deduction of the Constant of Precession, (St. Petersburg, 1842,) by 

 Otto Struve ; the Deduction of the Constants of Nutation and Aberrati<tn, by 

 Schidlufiski, (Dorpat, 1841,) by Lundahl, (Helsingfors, 1842,) and by Peters, 

 (St. Petersburg, 1842.) In conjunction with the last named memoii' is to be 

 placed the determination by Struve (St. Petersburg, 1843,) of the constant of aber- 

 ration from his own observations made in 1839-1842 with the Poulkova Eepsold 

 Prime Vertical Transit. This last w'as the first important publication of ol)serva- 

 tions made at Poulkova, and was shortly followed (1844) by Peters's Observa- 

 tions with the Ertel Vertical Circle upon the Pole Starj in both of which 

 works the scientific world found the proof of the superiority and accuracy of 

 these new instruments. The first publication of observations Avith the Merid- 

 ian Transit is found in Lindhagen's memoir (St. Petersburg, 1849) upon the con- 

 stant of aberration deduced from observations made on the Pole Star. 



These works of universal interest and im})ortance, inasmuch as they have 

 established the authority of the so-called " Poulkova Constants," now in general 

 use among astronomers, were accompanied by others of similar value : such were 



