LIFE IN OTHER WORLDS 



equal to several of ours, and when night comes there 

 the temperature sinks to a level colder far than that 

 of the earth's Arctic regions ; so cold, in fact, that even 

 gases would be turned to liquid and then frozen solid. 

 It is by no means certain that the gases we have men- 

 tioned would support vegetable life, but assuming that 

 they would, we should then expect the vegetation to 

 spring up with extraordinary rapidity because it would 

 be so little hampered by its own weight when the 

 vertical rays of the Sun were beating down on the Moon. 

 When that was the case the temperature there would 

 be from 500 (F.) to 600 (F.) higher than during the 

 night. 



Perhaps we may here explain some of the reasons why 

 vegetation would be little hampered by its own weight 

 on the Moon. It is similar to the reasons why light 

 gases escape from the Moon. The mass of the Moon 

 that is to say, the amount of matter it contains is gVth 

 that of the earth. Therefore since the weight of a 

 body means the measure of the force by which gravity 

 attracts it (to the earth or to the Moon), bodies on 

 the Moon's surface are much lighter than they are here. 

 The ratio is almost exactly one-sixth ; consequently a 

 man weighing 180 Ibs. on the earth if transplanted to 

 the Moon would find that he only weighed 30 Ibs. there, 

 arid could carry two men at once on his back for twenty 

 miles much more easily than he could walk that distance 

 without a load here. He could throw a stone six times 

 as far as on the earth, and jump six times as high. 

 Indeed, jumping over a moderate-sized house would be 



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