THE 



POPULAR SCIENCE 



MONTHLY. 



SEPTEMBER, 1902. 



AREOGRAPHY. 



BY PERCIVAL LOWELL, 



Vidi ego, quod fuerat quondam solidissima tellus 

 Esse f return: vidi faetas ex acquore terras; 



Ovid, Metam, xv., 262. 

 " What onee was solid ground I've seen to be a strait: 

 Lands I've seen made from out the sea." 



TT AD Ovid not let Pythagoras say this intentionally of the Earth 

 -* — *- he might be credited with having meant it for Mars. So start- 

 lingly apposite is its application to the history of Martian discovery. 

 For the verse expresses to a presentment the course of man's acquaint- 

 ance with that planet. A surface supposed at first partly land and 

 sea; the land next seen to be seamed with straits; and lastly the sea 

 made out to be land. Such is the history of the subject, and words 

 could hardly have put the facts more neatly. 'Vidi ego, quod fuerat 

 quondam solidissima tellus esse f return' sounds like Schiaparelli's own 

 announcement of the discovery of the canals. Indeed I venture to 

 believe he would have made it had he chanced to remember the verse. 

 'Vidi faetas ex acquore terras' certainly sums up what has since been 

 found for the seas. 



Three stages mark the course of Martian map-making from its 

 beginning sixty-odd years ago to the present day. They constitute three 

 epochs in the subject, which may be recognized distinctly in the chain 

 of successive charts made of the surface of the planet from then till 

 now. Such a series, however, is not for most people obtainable. Only 

 to specialists is the evidence for or against any scientific belief present 

 at any time in its entirety. Not only has the new evidence not had 

 time to filter through the usual channels into general absorption, but 



VOL. LXI. — 25. 



