THE AUTHOR'S THEORIES OUTLINED 49 



whole elaborate theory erected by Lowell falls away with 

 it. Such evidence will be adduced in plenty in a later 

 chapter. 



But if these lines undeniably exist, and if they are 

 not designed for irrigation, what in truth are they? 

 Shall we still cling to the notion that they cannot exist 

 naturally, and cast about for some other motive to 

 explain them? 



My conception is that these lines veritably exist, to- 

 gether with the dots at their intersections, but, in view of 

 the immense difficulties in the work of observation, I do 

 not accept these marks as anything like as regular and 

 uniform as the Lowellians would have us believe. As- 

 suming them to be due to natural causes, the question 

 at once confronts us as to whether such geometrical out- 

 lines as we here have to deal with cannot more easily 

 come into existence on an ocean surface than on a land 

 surface. Heretofore it has been precipitately assumed 

 that marks of any sort can be retained permanently only 

 on the continental areas, and this has been the chief 

 reason (inasmuch as the lines principally affect what 

 appear to be ocean surfaces) why Mars has so long been 

 believed to be a desert planet. 



Having carefully weighed all the foregoing matters 

 separately, as well in their mutual relations, I have ar- 

 rived at the following conclusions : 



1. That Mars is endowed as generously as the earth 

 with atmosphere and oceans in proportion to his mass. 



2. That on account of his greater distance from the 

 sun and his consequent lack of warmth, his oceans are 

 frozen to at least one-half their depth. 



3. That the remainder of his surface (correspond- 

 ing with our continental areas) because of its slight eleva-' 

 tion above the ocean level, is of a marshy nature, much 

 diversified with ponds, lakes, inlets and connecting 

 straits. 



4. That with the alternation of seasons, and of day 

 and night, rain and snow fall upon this ice crust and give 



