98 FROM NEBULA TO NEBULA 



show activity of a certain kind immediately following 

 the incipient thawing of the snow-cap, and that this ac- 

 tive movement travels equatorward at the rate of 51 

 miles a day for a distance of 3300 miles. As to the na- 

 ture of this change we can judge only from appearance, 

 which, he avers, consists in a gradual darkening and 

 broadening of the canal lines, and is construed by him to 

 be due to stimulated vegetation. 



6. The ancient "sea bottoms" Mr. Lowell infers to 

 be regions of vegetation, on account of their color. Yet 

 they too, he declares, exhibit "canals," not only enter- 

 ing from the nearest pole of supply, but rising again into 

 the arid regions nearer the equator. This feat of canal- 

 izing the basin of an ocean and thence raising the water 

 to the farther shore Mr. Lowell cites as an evidence of 

 Martian engineering prowess. 



7. Philosophically speaking, the evolution of life 

 from matter is the order of nature. Mars, whether or 

 not older than our planet, presumably cooled earlier, 

 both because smaller in size and more remote from the 

 sun. Hence, he argues, it has already run the gamut of 

 evolution, and by the principle of survival of the fittest 

 the present Martians must be the highest products of 

 their race. Historically, they have witnessed the birth 

 of a world, and seen it pass through its seven ages into 

 that of the sere and yellow leaf. Even the seas have 

 dried up, partly by absorption into the interior and 

 partly by the escape of the molecules into the outer air. 

 The race is at bay, being driven slowly, but none the 

 less inevitably, to extermination by the road of thirst, 

 for the snow caps must be thinning year by year, and 

 eventually must altogether vanish. 



Thus far Prof. Lowell's argument, which I have 

 aimed to give as fairly and fully as the present circum- 



