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LXXXVII. An Account of a General Siirveij of the Heavens 

 undertaken at the Konigsberg Observatory. Bj/ Professor 

 Bessel *. 



The Histoire Celeste has enabled us to acquire a more com- 

 plete knowledge of the firmament than the world had ever 

 before received upon the subject. It has detailed the stars 

 from the north pole to the southern tropic, down to the 8th 

 magnitude inclusive, and even some of a still smaller magni- 

 tude, with great accuracy : whilst formerly those only of the 

 telescopic stars were known which had accidentally presented 

 themselves to the eye of the astronomer. The observations 

 contained in the Histoire Celeste are as accurate as it is rea- 

 sonable to expect : the places of the stars may be taken from 

 it with sufficient exactness to ascertain every astronomical fact, 

 by uniting it with the second great undertaking of our time, 

 the Catalogue of Piazzi. The Histoire Celeste lays the foun- 

 dation for a new epoch in the science of astronomy, which em- 

 braces the knowledge of the firmament by means of its mani- 

 fold connexion with other branches of knowledge, which hence- 

 forth demand the utmost attention from astronomers. 



However much the Histoire Celeste may have developed the 

 subject, it has bv no means precluded further inquiries. It is, 

 on the contrary," necessary that these rej^eated and desirable 

 observations should be extended to the smaller stars; by which 

 means we may become possessed of a perfect catalogue and 

 chart of all the stars down to the ninth magnitude inclusive. 



Repetition is necessary, in order not only to give more ac- 

 curacy to the determinations, but likewise to obtain a sketch 

 of the proper motions of the stars, and to correct those errors 

 of the pen and the press, Avhich too frequently occur. The 

 extension of the investigaticm to all stars of the 9th magni- 

 tude, is, on the contrary, an arbitrary inquiry, which can and 

 must be accomplished, "if we are desirous of rendering more 

 perfect the astronomy of the present age, or of leavmg to 

 posterity tlie means of acquiring a more complete knowledge 

 of the heavens. This perfection is the only desideratum ; but 

 it is not by meridian observations alone that this information 

 is to be obtained, since many stars (especially in those regions 

 which are cnnvded \s\i\\ stiu-s) are generally passed over unseen 

 or unnoticed. It is possible, however, to observe sufficient to 

 enable us to mark the remaining ones on the chart from their 

 relative positions estimated with the eye, without any material 

 uncertainty ; whereby these at least attain the desired accu- 



• Frpin M. Schumacher's AHroMmmche Nachr'wtiteu, No. 17. 



.J H y racy. 



