94 FROM NEBULA TO NEBULA 



It is not my desire to single out any particular au- 

 thor for discussion, but Prof. Lowell has so closely iden- 

 tified his name with that of Mars as to render impossi- 

 ble the consideration of that planet without reckoning 

 with him. We must either be for him, or against him. 

 Either we must yield ourselves converts to his theory, or 

 we must perforce explain away by natural causes the 

 deep mystery underlying the so-called "canals" of Mars. 

 This I shall here attempt to do, not by disputing the 

 genuineness of his observations, but by interpreting 

 them in a more natural way. 



In order to prepare the reader to comprehend what 

 follows, I shall attempt a brief summary of Prof. Low- 

 ell's facts and of his method of interpreting them, quot- 

 ing in some cases his own language. 



1. "Mars' surface is singularly devoid of irregu- 

 larity. The more minutely it is viewed the more its 

 levelness grows apparent. Calculation shows that 

 heights even of very moderate elevation should be vis- 

 ible if such existed and none show." 



2. Being approximately one and a half times far- 

 ther from the sun than is the earth, Mars receives, area 

 for area, four-ninths as much heat. 



3. Mars' surface gravity is but thirty-eight per 

 cent of the earth's. The atmospheric pressure too is 

 much less. 



4. "The northern snow cap diminishes from 78 

 to 6, the southern dwindles from 96 to nothing." 



5. "Excluding the polar caps the surface consists 

 of large robin's-egg-blue patches indiscriminately placed 

 upon a general background of rose ochre, the relative 

 areas being 3/8ths to 5/8ths. The tints frequently vary 

 in shade and grade off insensibly into each other thus 

 making regions of intermediate color but the precise 

 borders of which are not decipherable by the eye." The 



