ADVANCE OF ASTRONOMY. 295 



that if these lines were much narrower than forty miles they would 

 be invisible. Each of them is marvelous in its uniformity through- 

 out its entire length. 



The existence of these straight lines on the planet contains per- 

 haps the first suggestion of the presence of some intelligent beings 

 on Mars. The mere occurrence of a number of perfectly straight, 

 uniform lines on such a globe would in itself be a sufficiently re- 

 markable circumstance. But there are other features exhibited 

 by these objects which also suggest the astonishing surmise that 

 they have been constructed by some intelligent beings for some 

 intelligent purposes. 



Sometimes two of these lines will start from a certain junction, 

 sometimes there will be a third or a fourth from the same junction ; 

 in one case there are as many as seven radiating from the same 

 point. Such an arrangement of these straight lines is certainly 

 unlike anything that we find in JSTature. We are led to seek for 

 some other explanation of the phenomenon, and here is the expla- 

 nation which Mr. Lowell offers: 



It has recently been found that there are no oceans of water 

 on the planet Mars. In earlier days it used no doubt to be be- 

 lieved that the dark marks easily seen in the telescope could rep- 

 resent nothing but oceans, but I think we must now give up the 

 notion that these are watery expanses. Indeed, there is not much 

 water on that globe anywhere in comparison with the abundance 

 of water on our earth. It is the scarcity of water which seems to 

 give a clew to some of the mysteries discovered on Mars by Schia- 

 parelli and Lowell. 



As our earth moves round the sun we have, of course, the 

 changing seasons of the year. In a somewhat similar manner 

 Mars revolves around the sun, and accordingly this planet has also 

 its due succession of seasons. There is a summer on Mars, and 

 there is a winter; during the winter on that globe the poles of 

 the planet are much colder than at other seasons, and the water 

 there accumulates in the form of ice or snow to make those ice-caps 

 that telescopic observers have so long noticed. In this respect 

 Mars, of course, is like our earth. The ice-cap at each pole of 

 our globe is so vast that even the hottest summer does not suffice 

 to melt the accumulation; much of the ice and snow there remains 

 to form the eternal snow which every arctic explorer so well knows. 

 It would seem, however, that the contrast between winter and sum- 

 mer on Mars must be much more deeply marked than the contrast 

 between winter and summer on our earth. During the summer of 

 Mars ice and snow vanish altogether from the poles of that planet. 



Mr. Lowell supposes that water is so scarce on Mars that the 



