\i6 Statement of a Plan for fATJo. 



that may be perfect to a certain limit ; and the more desirable 

 the further this limit be removed. If we determine that limit 

 by the smallest stars yet visible through one of Fraunhofer's 

 comet-seekers of 34 lines aperture and a magnifying power of 

 K) times, (and which can be observed without difficulty by 

 Reichenbach and ErtePs meridian circles, provided with Fraun- 

 hofer's telescopes of four inches aperture, in an illuminated 

 field,) we shall seldom or never find a deficiency in the astrono- 

 mical apphcation of the charts, and shall obtain a result, the 

 surpassmg of which would not only be extremely difficult, but 

 would be prejudicial for obtaining a general view, owing to the 

 excessive number of stars which it would be necessary to intro- 

 duce. But this detail being once attained, the charts will show 

 us at once any thing new, on comparing any part of them with 

 the heavens, provided the magnitude of the star be not less than 

 the limit assumed. Besides the interest naturally attached to a 

 more correct view of the heavens generally, and the facility 

 thereby obtained for many astronomical observations, such 

 charts would also offer the surest means of enlarging our know- 

 ledge of the solar system, by the discovery of new planets. 

 Nay, such a result will be highly probable, whilst without such 

 special celestial charts they can only be found by some lucky 

 chance. 



Indeed, there have been repeated attempts towards construct- 

 ing charts of this description : and although they have not been 

 crowned with success, it will be sufficient to enumerate the 

 causes that have impeded their execution, in order to show that 

 they are not now insuperable. The perfection of the celestial 

 charts to a certain limit can only be attained by first laying down 

 on a net work,* or scale, those stars that have been determined 

 by meridional observations, in order that all the rest, intended 

 to be introduced, may be added from estimation by the eye, per* 

 haps assisted too by some instrument. By meridional observa^ 

 tions alone, even if repeated more than once, we cannot acquire 

 the certainty of having all the stars within the assumed limit. 

 Even the Histoire Celeste contains much fewer stars than are 

 necessary as a basis for perfect charts ; wherefore it was neces- 

 sary to make de novo, a more numerous series of meridional ob- 

 servations. Such a one has now been made at the observatory 

 of Konigsberg, extending over a circular zone of the heavens 

 from —15° to + 15° dechnation, and containing about 32,000 

 stars ; which, according to an experiment made in a part of the 



♦ [Thisnc/ work is delineated on the copper-plate engraving which accompanied the 

 original communication, and which was sent as a pattern. It consists of 100 small 

 squares, formed of faint lines, half an inch (£ng.) asunder ; each square comprehending 

 a degree. It is formed on the plan, and on the same scale, as Harding^s Atlas; ana 

 therefore it is unnecessary to give a specimen of it here. The plate itself is given in 

 Schumacher's Astron. Nach. No. 88 ; aad it may be seen by application to the Secre- 

 tary of the Astronomical SJociety^— -Sec. ] 



