40 Physiognomy of the MootCs Surface. 



We may admit it as probable, that there are regions on that 

 hemisphere of the moon which is concealed from us, analogous to 

 those to which we have been adverting : for, first, apart of those 

 which we see, advance to the very edge ; and again, there are 

 two portions of this appearance, the one of which has been 

 named Kaestner by Schroeter, and to the other of which, larger 

 and lying to the north-west, we have given the name of Hum- 

 boldt, which only commence on the side of the moon which is 

 turned toward us, and whose further limits cannot be discovered, 

 even at the epoch of the libration, of all others the most favour- 

 able for its perception. 



The bright parts of the moon are almost always mountain- 

 ous, and these mountains surpass the most elevated of the earth, 

 if not in absolute elevation, at least in steepness. Sometimes, 

 though more rarely than on our planet, we perceive simple ranges 

 of isolated summits and small projections ; but far more fre- 

 quently we discover vast masses heaped together, widely ex- 

 tended, and cut by deep transverse valleys. Occasionally, too, 

 we observe rising up, pretty extensive portions of surface, form- 

 ing a plateau, whence proceed many mountains of different 

 shapes, and at the side of which there exists a very high 

 eminence, whose lofty escarpments descend perpendicularly 

 even to the plain. The Apennine, which is the most remark- 

 able mountain of this last description ( Randgehh'ge) has its 

 summit as high as 18,000 feet ; and it would appear from the 

 treatise of Plutarch, De Jade in Orhe Lunee, that it had been 

 observed by the ancients. Towards the conclusion of the first 

 quarter of the moon, it forms so marked a protuberance on the 

 dark part of the disk, that it might possibly be distinguished 

 by the naked eye. Besides these more common appearances, 

 there are also observed upon the moon's surface lower moun- 

 tain ranges, and hilly regions. Finally, there likewise exist, 

 and in greater number than on the earth, mountains which are 

 quite isolated, and which are endowed with every variety of form 

 and dimension. Some of these exhibit themselves as ranges 

 without any determinate connection ; and sometimes they form a 

 regular circular zone round an enclosed space, which space is 

 on all sides connected with the exterior by lateral valleys. 



These circles of the mountains (Bergkranze) lead us to very 



