194 MEMOIR OF ENCKE. 



was studying theology, to serve under tlie Pmssian standai'd. He seems to have 

 affixed to his offer of service a testimonial wherein Gauss certifies that Encke 

 had '' at first attended and afterwards borne an active part in his manifold astro- 

 nomical occupations and labors, and had manifested throughout distinguished 

 talent, great diligence, and uncommon knowledge." The brothers were required 

 to undergo an examination, which, in the case of our astronomer, at least, Avas 

 never repeated. He received, June 10, 181-5, the commission of second lieu- 

 tenant of artillery, and was first ordered to Thorn, and later to Graudenz. 



Encke would, proVjably, like his brother, have still further pm'sned a military 

 career had not Von Lindenau, the director of the Seeberg observatory, at the 

 recommendation of Gauss and Gerling, ofiered him in the beginning of 1816 the 

 place of adjunct' therein. This induced him to ask a discharge from the army, 

 Avhich was accorded on the 8th of March. Hereupon he went once more to 

 Gottingen, and remained there till July 5, 1816, when his nomination to the 

 observatory was confirmed. The appointment was by no means dazzling. The 

 salary was but $15 a month, and the place of service consisted of a garret so 

 lowly that he touched the ceiling when he raised his hand above his head. Not 

 the less did there go forth from hence such labors as soon turned the general 

 attention on the young astronomer. With so much zeal did Encke apply him- 

 self to his duties that only oiice a week did he leave the observatory and go to 

 Gotha. 



He first occupied himself with the newly discovered small planets, especially 

 Vesta, whose orbit he traced with superior accurac}', and of whose apparent motion 

 he puljlished the ephemerides. Another labor, if one of subordinate importance, 

 was not without consequence by placing him in friendly correspondence with 

 Bessel. The Fimdamenta Astronomice had been printed at Gotha, and Lindenau, 

 on whom the correction of the press devolved, transferred this task to his assistant. 

 Encke, however, did not confine himself to a comparison of the manuscript with 

 the impression, but repeated the calculations. Hence Bessel says, in the preface 

 to his work, '' Mr. Encke, who occupies the second place in the Seeberg 

 observatory, but who would be an ornament to the first, has given himself with 

 unsurpassed skill to the revision of the imprint, even to the detection and cor- 

 rection of the eiTors of the manuscript. I must acknowledge this with the more 

 thankfulness, inasmuch as his time is worthily occupied with his own astronomical 

 researches, and between us no other bond exists than that which embraces all 

 who devote themselves with zeal to the same science." 



The first of the more important labors of Encke relates to the comet of 1812.* 



This had been observed for two months at all the greater observatories. Encke 

 had, at his first residence in Gottingen, and therefore immediately on the appear- 

 ance of the comet, begun tlie calculation which, in the well-considered and careful 

 employment of numerous observations and the exact execution of extended com- 

 putations, takes rank with the most admirable investigations of this nature. It 

 was crowned Avith a special result, since an elliptical orbit corresponded with 

 the revolution of nearly 71 years. 



How important this discoA'ery Avas considered at that time is seen fi'om a letter 

 of Bessel's : '^ You have adduced the strongest proof for the shortness of the 

 revolution of this comet, and placed the result in the clearest light. We have 

 now, since we begin more narrowly to observe and to calculate the comets, quite 

 other views to maintain. Haliey's comet seemed only to be an exception. As 

 regards that of Olbers, I scarcely trusted my own calculation, as this gave but a 

 middling revolution. Yours is now the third. Our successors, through an exact 

 investigation of the planet-masses, Avill be enabled to recognize the true move- 

 ment of the heavenly bodies Avith a perfection of which we have scarcely an idea." 



* In the second volume of the Zeitschrift filr Astronomic und verwandte Wissenschaften, 

 p. 337 et seq. 



