Marvels of the Universe 



149 



sphere not illuminated is extremely low, water- 

 vapour or carbonic acid gas is 3-et given off 

 from the depths of these craters, and condenses 

 in the form of hoar-frosts or snow on the 

 interior of the bounding walls. The first rays 

 of the rising sun dissolve these deposits : the 

 ice melts, the snow evaporates and becomes 

 in\isible, and the crater reappears in its normal 

 condition. This is precisely the impression 

 created bj- the present (1911) observations of 

 Caquet. 



During the three hundred and fifty-four hours 

 of sunshine which constitutes the lunar day, 

 the surface of the soil must reach a point of 

 temperature a good deal higher than that of our 

 most burning desert or of the equatorial regions ; 

 for the heat must reach very nearly to one 

 hundred degrees Centigrade and even more, 

 perhaps even to nearly two hundred degrees in 

 those parts which receive the solar rays perpen- 

 dicularl}- ; for they are never lessened by clouds 

 nor the presence of fog, nor even of air, since 

 the atmosphere which around the earth acts as 

 a filter to strain the rays coming from the sun, 

 and as a shield to hinder them from escaping 

 and being lost in space, is so rarefied upon the 

 moon that its effect is almost nil. 



This great white globe, turn by turn too 

 hot or frozen, whose great spots, dark and 

 grey, mark the beds of dried-up seas ; this world 

 without water and with little air ; this neigh- 

 bouring habitation appears by no means hos- 

 pitable. 



Nevertheless, I possess upon the moon, to- 

 wards the centre of the visible hemisphere, a 

 property of considerable dimensions, the Circle 

 of Flammarion, with a diameter of 33 miles ; 

 but I verj' much fear that it is rather a sterile 

 property. 



At the epoch when our world was yet only 

 a mighty chaos, and was preparing itself slowly 

 by the incessant travail of its elements for the 

 future sojourn of humanity, the moon, more 

 advanced in its planetary evolution, had probably 

 given shelter for millions of years to living forms 

 fitted by nature for the special conditions of 

 life on her world. But she has grown old more 

 quickly than our terrestrial habitation. 



But it is not necessarily to be supposed that 



I'liolo hi/] 



[i: ]',,,.<■ 



THE MOON ON THE WANE. 



/'An/o '.'i;] I'/'lir Uek Ubsermlarji. 



THE MOON IN THE LAST QUARTER. 



Aged twenty-three days, eifiht hours. 



