

Curiosities of Science. 71 



slight degree of Heat (see Things not generally Known, p. 7) ; 

 and Professor Piazzi Smyth, from a point of the Peak of Tene- 

 riffe 8840 feet above the sea-level, has found distinctly per- 

 ceptible the heat radiated from the moon, which has been so 

 often sought for in vain in a lower region. 



SCENERY OF THE MOON. 



By means of the telescope, mountain-peaks are distinguished 

 in the ash-gray light of the larger spots and isolated brightly- 

 shining points of the moon, even when the disc is already 

 more than half illuminated. Lambert and Schroter have shown 

 that the extremely variable intensity of the ash-gray light of 

 the moon depends upon the greater or less degree of reflection 

 of the sunlight which falls upon the earth, according as it is 

 reflected from continuous continental masses, full of sandy de- 

 serts, grassy steppes, tropical forests, and barren rocky ground, 

 or from large ocean surfaces. Lambert made the remarkable 

 observation (14th of February 1774) of a change of the ash- 

 coloured moonlight into an olive-green colour bordering upon 

 yellow. " The moon, which then stood vertically over the 

 Atlantic Ocean, received upon its right side the green terres- 

 trial light which is reflected towards her when the sky is clear 

 by the forest districts of South America. " 



Plutarch says distinctly, in his remarkable work On the Face 

 in the Moon, that we may suppose the spots to be partly deep 

 chasms and valleys, partly mountain -peaks, which cast long 

 shadows, like Mount Athos, whose shadow reaches Lemnos. 

 The spots cover about two-fifths of the whole disc. In a clear 

 atmosphere, and under favourable circumstances in the position 

 of the moon, some of the spots are visible to the naked eye ; 

 as the edge of the Apennines, the dark elevated plain Grimal- 

 dus, the enclosed Mare Crisium, and Tycho, crowded round with 

 numerous mountain ridges and craters. 



Professor Alexander remarks, that a map of the eastern 

 hemisphere, taken with the Bay of Bengal in the centre, would 

 bear a striking resemblance to the face of the moon presented 

 to us. The dark portions of the moon he considers to be con- 

 tinental elevations, as shown by measuring the average height 

 of mountains above the dark and the light portions of the 

 moon. 



The surface of the moon can be as distinctly seen by a good 

 telescope magnifying 1000 times, as it would be if not more 

 than 250 miles distant. 



LIFE IN THE MOON. 



A circle of one second in diameter, as seen from the earth, 

 on the surface of the moon contains about a square mile. 



