NEWS FROM THE MOON. 22/ 



northern extremity of the lunar valley which runs past 

 the eastern edge of Eheita. Describing the first, 

 Frankland says, there are c two ridges forming the 

 arcs of eccentric circles. Beyond the second ridge a 

 talus slopes down gradually northward to the general 

 level of the lunar surface, the whole presenting an 

 appearance reminding the observer of the concentric 

 moraines of the Ehone glacier. These ridges are 

 visible for the whole period during which that 

 portion of the moon's surface is illuminated; but it 

 is only about the third day after the first quarter, 

 and at the corresponding phase of the waning moon, 

 when the sun's rays, falling nearly horizontally, throw 

 the details of this part of the moon's surface into 

 strong relief, and the appearances suggest this expla- 

 nation of them.' It will be manifest that the evi- 

 dence for glaciers on the moon is not altogether 

 irresistible. On the whole face of that hemisphere, 

 seven millions of square miles in extent, which the 

 moon turns earthwards, there are but two spots where 

 appearances are recognised which suggest the idea of 

 glacial moraines. This is not convincing, especially 

 when we remember that under the best telescopic 

 scrutiny yet applied to the moon we see her surface 

 only as we should see a mountain region on the earth 

 from a distance of more than one hundred miles, and 

 through a dense and perturbed atmosphere. For all 

 the atmospheric effects are multiplied precisely in 

 proportion to the power of the telescope employed, so 

 that even when we use so high a power as 2,400, which 



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