354 M. Bessel on a new Method qfjinding 



it would amply repay the labour. I must apologize to your 

 readers for the mistakes which will be found in the investi- 

 gation. I already see several which it is impossible now to 

 correct. I have been forced to draw it up during moments of 

 leisure snatched now and then from the toils ot a laborious 

 employment, and of a host of other less congenial though more 

 necessarv pursuits. Let this stand for my excuse. Detached 

 and fragmentical as it is, I hope that my leading purpose is in 

 some degree accomplished. The general inquiry, however, 

 into the decomposition of B^ is much more interesting and 



more practically useful ; and as soon as I can command suffi- 

 cient time to commit to paper the substance of what exists in 

 my imagination respecting it, I will lay it before you with my 

 best ability. 

 April 15; 1823. 2. 



LVI. On the Determination of the Latitude of a Place Inj 

 Means of theJransit Instniment placed perpcndiadarly to the 

 Meridian. By Professor Bessel. Co7nmunicated in a Letter 

 to Professor ScuuMACiiF.R, dated Konigsberg, Feb. 2, 1824.* 



"l^^HEN, in the year 1819, 1 saw you at Lauenbui'g, and re- 

 * ' marked to you that it might be advantageous to determine 

 the differences of the altitude of the pole (for the purpose of mea- 

 suring geographical degrees) by means of a transit instrument, 

 moving nearly perpendicular to the meridian, I had in view 

 the difficulties often experienced in observing zenith distances. 

 This difficulty is certainly removed by Ramsden's zenith sector, 

 used in the English admeasurement of degrees for observing 

 the differences of latitude, as well as by yourself and M. Gauss 

 in your great undertaking of the same kind. It is also I'e- 

 moved by the employment of Reichenbach's meridian circle 

 for the purpose of measuring the zenith distances of stars pass- 

 ing near the zenith ; for it is with such stars that the instru- 

 ment gives the correct results, without the investigation of 

 other zenith distances. I do not wish to refuse the fullest 

 confidence to such means for obtaining the differences of lati- 

 tude : therefore any other proposal might at present appear 

 superfluous. 



But if we are desirous to obtain a certain degree of accu- 

 racy with much less trouble, or try the results already ob- 

 tained by a different method, I have no doubt but that it might 

 be effected by the method which I am about to propose. My 

 intention is to avoid entirely the divisions of the circle, and 



* From Scluimacher's Astronomische Nachrichten, No. 49. 



to 



