THE MOON LANDSCAPE 13 



Looking again, after some hours interval, into the great cratered 

 amphitheatre, we see that the rays of the morning sun have crept 

 down the distant side of the rampart, opposite to that on which we 

 stand, and Hghted up its vast landsHpped terraces into a series of 

 seeming hill-circles with all the iiide and rugged features of a 

 terrestrial mountain view, and none of the beauties save those of 

 desolate grandeur. The plateau of the crater is half in shadow 

 10,000 feet below, with its grand group of cones, now fully in sight, 

 rising from its centre. Although these last are 20 miles away and 

 the base of the opposite rampart fully double that distance, we 

 have no means of judging their remoteness, for in the absence of 

 an atmosphere there can be no aerial perspective, and distant 

 objects appear as brilliant and distinct as those which are close to 

 the observer. Not the brightness only but the various colours 

 also of the distant objects are preserved in their full intensity; for 

 colour we may fairly assume there must be. Mineral chlorates 

 and sublimates will give vivid tints to certain parts of the land- 

 scape surface, and there must be all the more sombre colours 

 which are common to mineral matters that have been subjected 

 to fiery influence. All these tints will shine and glow with their 

 greater or less intrinsic lustres, since they have not been deterio- 

 rated by atmospheric agencies, and far and near they will appear 

 clear alike, since there is no aerial medium to veil them or tarnish 

 their pristine brightness. 



In the lunar landscape, in the line of sight, there are no means of 

 estimating distances; only from an eminence, where the interven- 

 ing ground can be seen, is it possible to realize magnitude in a lunar 

 cosmorama and comprehend the dimensions of the objects it 

 includes. 



And with no air there can be no diffusion of light. As a conse- 

 quence, no illumination reaches those parts of the scene which do 

 not receive the direct solar rays, save the feeble amount reflected 

 from contiguous illuminated objects, and a small quantity shed by 

 the crescent earth. The shadows have an awful blackness. As 

 we stand upon our chosen point of observation, we see on the 

 lighted side of the rampart almost dazzling brightness, while 

 beneath us, on the side away from the sun, there is a region many 

 miles in area impenetrable to the sight, for there is no object 

 within it receiving sufficient light to render it discernible; and all 

 around us, far and near, there is the violent contrast between 



