20. 



ON PROFESSOR CHALLIS'S NEW THEOREMS RELATING TO THE MOON'S 



ORBIT. 



[From the Philosophical Magazine, Vol. vui. (1854).] 



IN the June Number of your valuable Journal, Professor Challis calls 

 attention to some circumstances connected with his withdrawal of a paper, 

 relating to the Moon's motion, which he had communicated to the Cam- 

 bridge Philosophical Society, and of the principal results of which he had 

 given an account in your Number for April (p. 278). 



Professor Challis mentions that one of the reporters, whose unfavourable 

 judgement led to this withdrawal, had of his own accord communicated to 

 him some of the reasons on which this judgement was based. Professor 

 Challis, however, thinks these reasons to be very unsatisfactory, and con- 

 sequently invites the reporter to discuss with him the questions on which 

 they are at issue, in the pages of the Philosophical Magazine. 



As I am the reporter thus referred to, I beg that you will allow me 

 to state some reasons which appear to me sufficient to prove, beyond a 

 doubt, that the principal conclusions of Professor Challis's paper are erroneous, 

 in order that he may have the opportunity, which he desires, of replying 

 publicly to my objections*. At the same time, I must decline to enter 



* It may be proper to mention that the opinion of the other reporter on the paper 

 perfectly agreed with my own. 



A. 17 



