Proceedings of the British Association. 551 



simple and easy of application, was not preferred to any other in deter- 

 mining longitudes ?— Sir Thomas Brisbane replied, that to say nothing 

 of the heavier amount of labour required in such observations, he need 

 only, in order to shew the superiority of Mr. Dent's method, state 

 the fact, that in a late attempt to connect the Royal Observatories of 

 London and Paris, backed by all the instrumental accuracy and un- 

 rivalled skill of the observers at these two distinguished observatories, 

 300 observations on moon-culminating stars had given a mean deviating 

 no less than thirty seconds from the truth. — The President observed, 

 that although the method of moon-culminating stars had, in theory, 

 promised considerable accuracy in the determinations of longitudes, yet 

 from some unexplained difficulties it had, in practice, fallen far below 

 the estimate that had been formed of it. 



FRIDAY. 



'Report of the Committee for the Reduction of the Stars in the 

 Histoire Celeste.' 



June 16, 1842. 



I have the satisfaction of reporting that the whole of the stars in the 

 Histoire Celeste have been reduced, agreeably to the method proposed : 

 those only being omitted for which there are no tables of reduction, and 

 that there is now remaining, of the grant for this purpose, the sum of 

 91., which will not be required in the further prosecution of this portion 

 of the work. But the main object of this undertaking will be defeated, 

 if the catalogue be not printed for general use and information. The 

 number of stars reduced is upwards of 47,000 ; and 1 have caused an 

 estimate to be made of the expense of printing 500 copies in an octavo 

 form. And it appears that the cost of paper and printing will be about 

 415/., but that 1000 copies will cost 100/. more. There is, however, 

 another expense which must be taken into the account, which is 

 the copying of the catalogue, in a proper order for the press, and 

 the correction of the press during the printing, which I apprehend will 

 be 60/. or 70/. more. Taking the whole of those estimates together, it 

 would appear, that 500 copies would cost about 500/. and that 1000 

 copies would cost about 600/. Should the British Association decide on 

 the printing of the catalogue, I would draw up a statement of the 

 method pursued in making the reductions, together with such other 

 remarks as might be requisite. This probably would not add another 

 sheet to the work. 



Francis Baily. 



