The Lunar Arctic Region. 51 



of the impossibility of identifying the spots called by Schroter 

 Lexell and J". J". Cassini. This is not very wonderful, as the 

 old Hanoverian has clearly placed them in the next quadrant, 

 on the other side of the First Meridian ! We shall revert to 

 this matter in its proper place, remarking only at present that 

 the harmonizing and rectification of the existing drawings of 

 the N. circumpolar region would be a task of considerable 

 difficulty. 



Very near the Pole lies Scoresby (our No. 7), a ring of con- 

 siderable depth and reflective power, and one of the best guide- 

 points in this ill-marked district. It has in the interior a crater 

 and two hills, which are very difficult to be perceived; its 

 form changes much of course with the libration, varying from 

 0*36 of the length to 0*09, when its contour as a crater can 

 no longer be recognized. 



The North Pole of the Moon lies in a mountainous district, 

 but on a far less magnificent scale than the one diametrically 

 opposite. The difference between the character of the lunar 

 Arctic and Antarctic regions is plainly seen by the shape of the 

 horns before the first or after the last quarter, the N. being far 

 less broken and irregular. There is no indication whatever of 

 snow. A separate map of this vicinity, very beautifully and 

 minutely executed, with a corresponding description, is given 

 in the Beitrdge * of Beer and Madler, from observations 

 taken under a conjunction of circumstances so peculiarly favour- 

 able as to be worthy of remark, for the encouragement of those 

 who may have been disheartened by frequent disappointments. 

 1834, Sept. 17, the moon was on the meridian at 12h. 2m., 

 with a S. latitude of 4° 59', and was full 9m. afterwards. This 

 remarkable coincidence was further favoured by such clearness 

 and stillness of atmosphere as sometimes cannot be met with 

 for a year together in the climate of Europe. An uneclipsed 

 moon of course cannot be " full," in the proper sense of the 

 word ; being always deficient on the side nearest the point of 

 opposition to the sun ; and consequently, instead of a circular 

 limb, the N. polar region exhibited shadows enough among its 

 ridges and hollows to bring out their true relief, and enable a 

 drawing to be made. The next night, and three nights at the 

 ensuing Full Moon, proved again so favourable that little had 

 to be added on future occasions. They have indicated the 

 exact site of the Pole in a level between two mountainous 

 ridges, and at the foot of a summit of 9400 feet. These heights 

 deprive it for ever of the direct light of day, but must bestow 



* The complete title of this valuable though fragmentary contribution to 

 modern astronomy is, Beitrage zur physischen Kenntniss der himmlischen Korper 

 im Sonnensysteme. It contains many original observations on the moon and 

 planets. There is a French edition also, entitled Fragrhens sur les Corps Celestes. 



