ENCKE THE ASTRONOMER. 03 



higher branches of mathematical calculation. He took 

 the difficult work of determining the orbital motions 

 of newly-discovered comets under his special charge, 

 and Dr. Bruhns tells us that every comet which was 

 detected during Encke's stay at Seeberge was subjected 

 to rigid scrutiny by the indefatigable mathematician. 

 Before long a discovery of the utmost importance 

 rewarded his persevering labors. Pons had detected 

 on November 26, 1818, a comet of no very brilliant 

 aspect, which was watched first at Marseilles, and then 

 at Mannheim, until December 29th. Encke next took up 



matical relations, and the same sequence of events, I here and there 

 used language closely resembling his. I fear this led for a while to some 

 misconception ; but I was fortunately able to show in Mr. De la Rue's 

 address to the Astronomical Society, on the same subject, passages yet 

 more strikingly resembling some in Mr. Wilson's paper (written sub- 

 sequently and quite independently). The fact would seem to be that, if 

 two persons describe the same events, and deal with the same mathe- 

 matical relations, it is almost certain that in more than one passage they 

 will use somewhat similar expressions. 



I was actually indebted to Mr. Wilson's paper for one illustration, 

 however that derived from the movements of a supposed artificial 

 moon ; and I think that, had his paper appeared in a magazine printed 

 for general circulation, I should have referred to it. As it was, this 

 seemed useless so far as the readers of the Quarterly Journal of Science 

 were concerned. The circumstances of the case were, indeed, far 

 from calling for a reference ; while I had in a sense made the illustra- 

 tion my own by detecting an important miscalculation in the original 

 (the amount of advance being either doubled or halved I forget which). 

 Had I referred to Mr. Wilson's paper, I must needs have mentioned 

 this mistake ; and it would have appeared as though I had no other 

 purpose in making the reference. 



I mention these matters to explain what I fear my esteemed fellow- 

 collegian was disposed at the time to regard as either a wrong or a 

 slight. Nothing was further from my intention than either. 



