218 SCIENCE PROGRESS 



In all cases the width, which is itself imperceptible, is estimated 

 by the intensity. That there is a range of 30,000 per cent, 

 in the intensity proves that the larger canals are nowhere 

 near the limit of vision — a conclusion amply verified by the 

 fact that many of the larger ones are clearly visible on photo- 

 graphs of the planet. All these canali are equally geometrical 

 in their appearance and it is inconceivable to those who see 

 them that they are anything but the work of intellect. They 

 are just what our study of the planet's conditions have led 

 us to expect. 



The existence of vegetation on Mars depends upon them 

 and conversely it is evident that the vegetation, for whose 

 production they were made, is a necessity to their makers. 

 It would be natural to suppose that on a planet capable only 

 of seasonal change due to water from either pole, each pole 

 would nourish its own hemisphere. That this is not so, is 

 another proof of artificial causes. For the vegetation caused 

 by Southern water spreads far into the opposite hemisphere — 

 defying all the laws of dynamics and symmetry. 



Of the ochreous regions of the planet nothing has been said. 

 There is little to say, in fact, as they are as changeless as the 

 Sahara. In these regions only the parts near the poles show 

 any change and this is of a doubtful nature. The conclusion 

 seems inevitable that they are deserts. Their extent is most 

 telling — for they indicate that the planet has advanced far in 

 its course towards death and are evidence of that scarcity of 

 water which is the sign of advancing age in planets. 



On the earth the same process of desiccation is going on. 

 There are two belts of desert. The most marked is the 

 northern one. Wherever there is land this desertism shows. 

 The Sahara, Arabia, Persia, Northern India and the Chinese 

 desert in the Old World and the deserts of Mexico and the 

 western part of the United States form links in this chain. 

 Historical and geological evidence points to the fact that the 

 belt is ever widening. 



On Mars things have gone much further. Indeed water 

 can only reach the more genial parts of the planet by means 

 of the gigantic canal system which we are led to conclude 

 has been made there in self-defence by intelligence. 



On earth the cry of humanity is for bread and the great 

 areas under wheat are perhaps the only changes which man 



