undertaken at the Konigsherg Observatory. 43^ 



fied wltli this result, considering the rapidity with which the 

 observations niu.>t have been made; and I beUeve that this de- 

 gree of exactness is sufficient for most piu-poses. The same 

 instrument, when read by the verniers, and used at perfect lei- 

 sure, gives the probable error of the declination in the neigh- 

 bourhood of the equator =0",76. That it is only about one- 

 third greater according to the observation of the zones, is 

 proved in part by the goodness of my apparatus, but still more 

 conclusively by the extraordinary care of my iriend Argelan- 

 der, "joithout w/iich the apparatus would have availed as little 

 as other good instruments in bad hands. The publication of 

 the observations v»i!l be j'early superintended. The first 

 S9 observations of zones made in the year 1821 are already in 

 the press. The form which I observed in them is not pre- 

 cisely the original one, which would have occupied too much 

 room ; but it would not be difficult to restore the numbers in 

 the form in which they were actually observed, which might 

 in some cases be useful. I give in the first column the mag- 

 nitude of the star; hi the second, the number of wires observed; 

 in the third, the time of observation reduced to the middle wire; 

 in the 4th and 5th, the result given by the subsidiary arc and by 

 the microscope ; and finally, in the Gth, the apparent declina- 

 tion: that is, affected with refraction. These latter are ob- 

 tained when the numbers of the 4th and 5th columns (re- 

 duced to degrees, mmutes and seconds) are added to the ap- 

 parent declination of the zero point of the microscoj)e, which 

 is found by the above-mentioned readings and the place of the 

 equator on the instrument. This, however, is determined by 

 double observations of the {jole-star; and the corrections which 

 are required on account of the small errors of division in the 

 circle, the bending of the telescope, and the weight of the sub- 

 sidiary arc and oi' the hammer, are by these means ajiplied. 

 Lastly, the correction of the time, allowing for the deviation of 

 the instrument from the meridian, is made in each zone for the 

 mean declination. In order to render the use of the rough 

 original observations as easy as possible, I hope, at the same 

 time with the observations, to publish tables of reduction si- 

 milar to those which I have projjosed for the Hlstoire Celeste. 

 I have already calculated these tables for the 39 zones observed 

 in 1821, and have also nearly reduced die 194 stars (the list 

 of which is annexed to this paper) to the year 1825. 



This notice may for the present suflice. During the ten 

 months' progress of this laborious undertaking I have ascer- 

 tained tiie difficulties which a successive survey of the whole 

 heavens, in the clinuite of Konigsbcrg, will have to encounter. 

 The number of years whicli will pas'j away before its comple- 



Vol. 60. No, 29G. Dec. \U2'L J I tion, 



