90 View of the Progress of 



XXXI. Littrow's Determination of the Right Ascension of 

 a. Aquilm. 

 From the observations at Konigsberg, and by a method sug- 

 gested by Professor Bessel, makes it, after forming 35 equations 

 of condition, and finding the minimum of the sum of the squares 

 oC the errors, IQ" 41' 45",180, for the beginning of 1815; that 

 is ',023, Qr ",35 of space, more than Bessel's new catalogue. 



XXXII. Extract of a Letter from Professor Bessel. 

 Observes that, whatever may be the true latitude of Greenwich, 

 the reduction of Bradley's observations requires the employment 

 of 51° . 28' . 39 ",6. 



XXXIII. Extract of a Letter from the Chevalier Bdrg. 

 Containing oppositions of the new planets, and of some others. 



XXXIV. Extract of a Letter from the Chevalier Gauss. 

 Containing the elements of Dr. Olbers's comet. 



XXXV. Extract of a Letter from the Baron Von Zach. 



A very interesting account of the operations of Captain W. H. 

 Smyth, of H. M. S. Aid, in the survey of the Mediterranean, with 

 a determination of the situations of a variety of important points ; 

 and with some particulars of the travels of Hornemann, and of 

 Captain Smyth's expedition to the petrified city in the interior of 

 Africa. The latitudes vary a minute or two from the determi- 

 nations of Gautier, published in the Connaissancc des Terns for 

 1821. 



iii. May and June. 



XXXVI. Zach's further Remarks on the Discordance of the 

 Italian Observations. 



Tlie author attributes an uncertainty of 3 ,5 even to the lati- 

 tude of Greenwich, at least with respect to the observations 

 made with levels or plumb-lines. In Italy he had before de- 

 tected errors of more than 20" in the latitudes of some ob- 

 servatories ; finding for Padua 45° . 24' . 2", for Bologna 



