THE MOON 357 



are at their maximum possible height, for, however much 

 they may be snowed upon, they cannot grow taller, for 

 the simple reason that their base becomes liquefied 

 and runs out pari passu. Now, snow is snow wherever 

 it may be, and if piled on the island of Cuba would, other 

 things equal, act as it does on the moon. Other things are 

 not equal, however, particularly in this matter of the 

 surface gravity, as just suggested ; consequently our Cu- 

 ban range could, automatically, never exceed a mile in 

 altitude. 



WHITE RAYS, BILLS, etc. Imagine, if you please, an 

 immense marsh 500 miles or so in diameter irregularly 

 cut up into all sorts of small patches of land separated 

 from each other by narrow strips of water of varying 

 depths, with here and there a larger expanse of land bear- 

 ing small ponds or lakes; and picture to your mind's eye 

 how such a scene would be transformed by such a process 

 of glaciation as I have described. In such a case, soon 

 after nightfall, every natural ledge of land, and every 

 ledge that by the sun's evaporation had become uncov- 

 ered, would again become decked with fresh snow, the 

 depth varying, of course, according to the controlling 

 circumstances. Indeed, twenty-four hours after the sun 

 had disappeared below the horizon, and perhaps earlier, 

 every square inch of the lunar landscape, every nook and 

 cranny, including even the beds of all the streams, lakes 

 and maria, would be covered with the mantle of white, 

 and this state of things would continue unmodified all 

 through the long night until close upon dawn. With 

 dawn, however, would begin the great thaw, and the solar 

 artist would occupy himself the ensuing day in etching 

 out the land shapes by, at first, melting the snow where 

 thinnest, which is to say, on the ancient water beds, and 

 subsequently accentuating his artistic effects from hour 

 to hour. In fine, the white rays are neither more nor less 

 than the persistent deeper deposits of snow piled on the 

 broader and originally more elevated and receptive 

 patches of the marsh land. 



