LIFE IN MARS. I2/ 



the stability of objects having equal dimensions would 

 be correspondingly reduced. On the other hand, the 

 winds which blow in Mars are probably, as Professor 

 Phillips has pointed out, exceedingly violent ; so that 

 to quote a striking paper which appeared last year in 

 the Spectator (in a review of my 'Other Worlds'), 

 6 if currents of air in Mars are of more than usual 

 violence, while the solidifying force of friction which 

 resists them is much smaller than here, it may be a 

 reasonable inference that " natural selection " has 

 already weeded out the loftier growing trees, which would 

 stand less chance in encounters with hurricanes than 

 our own.' The absence of prairies is not so easily ex- 

 plained, however; and the idea is in fact suggested 

 that some of those regions which have hitherto been 

 included among the Martial seas, are in reality regions 

 richly covered with verdure. Nor are we wholly 

 without evidence in favour of this view ; for there 

 is a certain very wide tract in Mars respecting 

 which the late Mr. Dawes remarked to me that he 

 found himself greatly perplexed. ' At times, 1 he said, 

 6 1 seem to see clear traces of seas there ; but at other 

 times I find no such traces.' These regions have accord- 

 ingly been regarded as extensive tracts of marsh land. 

 But the idea seems at least worth considering that they 

 may be forest regions or extensive prairies. 



There must needs be rivers in Mars, since the clouds, 

 which often cover whole continents, must pour down 

 enormous quantities of rain, and this rain-fall must find 

 a course for itself along the Martial valleys to the sea. 



