MEMOIR OF ENCKE. 201 



find Bcssel constvcainecl, as it were, to hcg of " the liiglily respected professor" 

 tbat lie would not allow tlieir correspondence to languish. " You cannot do mo 

 the injustice to suppose that any one in the world is dearer to me and more highly 

 confided in than yourself. Wherefore, then, a formality which, on ni}- part, haa 

 been long- ago discarded ?" 



That views and conceptions should sometimes have diffcrfed Avas, of course, 

 inevitable. I'he difterences, however, Avere calndy discussed in the correspond- 

 ence, but they failed not progressively to become more and more pronounced and 

 frequent. The last friendly letter Ijcssel closed with the words, " I cannot 

 imagine that different relations should find an entrance between us." Not the 

 less, however, did such relations find entrance, and that immediately. The 

 occasion was given far less by any single controverted points which had arisen 

 in the course of astronomical journalism than by the contrast of personal position. 

 Bessel, easily excited in oral as in written intercourse, as Atarmly maintained the 

 opinions which he conceived to be right as he emphatically repelled those opposed 

 to them, and so sometimes forgot that he who had begun earliest had not only 

 erected himself into a master, but expressly assumed a higher and more influential 

 position than was his due. Thus in one of the last letters Bessel styles himself 

 '' the experienced friend," and, as such, thought himself authorized to counsel and 

 warn, whereupon Encke explained " that he could only take the course which: 

 alone was consonant to his nature." 



Since 1837 only a few formal and professional letters had been exchanged.) 

 When Encke, however, in 1845, sought to obtain Bessel's views with regard to^ 

 a new edition of the treatise of Olbers on the calculation of the orbits of comets,; 

 he made, as in earlier years, various communications respecting his own labors,' 

 and added the assurance of his deepest concern for Bessel's afflictions. The 

 answer, besides the desired opinion, conveyed a thanliLful acknowledgment. At 

 the close of the same year Encke communicated the first result of the stellar 

 charts in the discovery of a new planet. A mutual approach was thus again in 

 progress, when some months later the death of Bessel occurred. 



The words which, from this place, Encke 20 years ago dedicated to the memory 

 of Bessel, contain the fullest recognition of his great services in behalf of 

 astronomy, but make no mention of the friendly relations which had existed 

 between them. On that subject nothing could be ventured without, at the same 

 time, recalling their later and well-known estrangement. However much that 

 estrangement is to be regretted, it now no longer forbids us to recur to a friend- 

 ship whicli not only endured with singular devotion fjr 30 years, but was of 

 great importance for the advancement of science. 



It only remains to recount the occupations of Encke's life during the last ten 

 years. The extensive calculations for the Year-book, if, to a certain extent, 

 devolved on the assistants, continually required his co-operation, and the more 

 as the numerous newly discovered planets were to be taken into consideration. 

 The academical functions connected with the editing of the stellar charts, the 

 discourses before the university, the participation in the observations at the 

 observatory, and in the accurate testing of the new and older instruments there 

 deposited, together with his activity in the commission of studies for the military 

 academy, anil in the deputation respecting the calendar, to say nothing of the 

 manilbhl inevitable demands which await the director of an observatory in a 

 larg(! cit}', all these api>ear so engrossing that we have only room for wonder 

 tliat Encke should still have found time for the communication of so large a 

 num1)er of scienlilic papers to the transactions of the academy, the astronomi- 

 cal Year-book, and various mathematical and astronomical journals. Many 

 of these relate to the execution <jf calculations, such as the method of least 

 S(piares, inter[)olation, the mechanical (piadrature and the like. The}' are chiefly 

 of astronomical import, and bear relation to the ])arallax of the sun and moon, 

 the dimensions of the terrestrial glolje, the constants of the Berlin observator\-, 

 the masses of the planets, the deterniinatiou of the orbits of planets and those 



