NOTES ON MARS. 165 



these so-called canal.s were in any respect analogous to the rivers which 

 we know on our own glol)e. It can, however, hardly be doubted that 

 if we assume the dark regions to be oceans the canals do really repre- 

 sent some extension of the waters of these oceans into the continental 

 masses. Other facts which are known about the planet suggest that 

 what seem to be vast inundations of its continents must occasionallv 

 take place. Nor is it surprising that such vicissitudes should occur 

 on a globe circumstanced like Mars. Here, again, it is well to remem- 

 ber the small size of the planet, from which we ma}^ infer that it has 

 progressed through its physical evolution at a rate more rapid than 

 would 1)e possible with a larger globe, like the earth. The sea is con- 

 stantly wearing down the land, but, by upheavals arising from the 

 intensely heated condition of the interior of our globe, the land is still 

 able to maintain itself above the water. It can, however, hardly 

 be doubted that if our earth had so far cooled that the upheavals 

 had either ceased or were greatly reduced the water would greatly 

 encroach on the land. On a small globe like Mars the cooling of the 

 interior has so far advanced that in all probability the internal heat 

 is no longer an effective agent for indirectly resisting the advance of 

 the water, and consequently the observed submergence is quite to be 

 expected. 



That there may be tj^pes of life of some kind or other on Mars is, I 

 should think, very likel}". Two of the elements, carbon and h3'drogen, 

 which are most intimately associated with the phenomena of life here, 

 appear to be among the most widely distributed elements throughout 

 the universe, and their presence on Mars is in the highest degree prob- 

 able. But what form the progress of evolution may have taken on 

 such a globe as Mars it seems totally impossible to conjecture. It has 

 been sometimes thought that the ruddy color of the planet may be due 

 to vegetation of some peculiar hue, and there is certainl}^ no impossi- 

 bility in the conception that vast forests of some such trees as copper 

 beeches might impart to continental masses hues not unlike those which 

 come from Mars. Speculations have also been made as to the possi- 

 bility of there being intelligent inhabitants on this planet, and I do 

 not see how anyone can deny the possibilit}^, at all events, of such a 

 notion. I would suggest, however, that as our earth has only been 

 tenanted by intelligent beings for an extremely brief part of its entire 

 history— say, for example, for about one-thousandth part of the entire 

 number of years during which our globe has had an independent exist- 

 ence—so we may fairly conjecture that the occupancy of any other 

 world by intelligent beings might be only a ver}^ minute fraction in the 

 span of the planet's history. It would therefore be highly improb- 

 able, to say the least of it, that in two worlds so profoundly different 

 in many respects as are this earth and Mars the periods of occupancy 

 by intelligent beings should happen to be contemporaneous. I should 



