76 



SCIENCE GOSSIP. 



in visibility and tint as the seasons pass, sometimes 

 becoming so narrow as to exceed the limit for 

 distinct vision, at other times widening and even 

 becoming double. Such yearly and seasonal 

 transformations render it nearly certain that they 

 are not water-channels (at least not in their entire 

 breadth), but broad zones of vegetation, probably 

 stimulated to active growth and luxuriance by 

 means of a net-work of irrigation-canals too 

 narrow to be individually discernible by our 

 telescopes at a distance of forty million miles or 

 upwards. 



The so-called "lakes" are the circular spots 

 (likewise blue-green in colour) which always occur 

 at the junctions of the " canals " ; they have also 

 been misnamed, for Mr. Lowell has conclusively 

 shown that they have a much better claim to be 

 termed " oases." The greater number are similar 

 in size, about 120 to 150 miles in diameter, with 

 one very notable exception, the " Eye of Mars " or 

 " Lake of the sun." This is a conspicuous elliptical 

 area in the midst of a large desert, but connected 

 by short " canals " (about 250 miles long) with the 

 greenish region of permanent vegetation to the 

 south, west and east. 



Now Mars must, on the whole, be remarkably 

 deficient in water ; indeed, the whole supply seems 

 to be derived from the annual melting of the 

 polar ice-caps. As the summer proceeds, the ice- 

 cap is seen to diminish in size and to be sur- 

 rounded by a dark blue zone, which must clearly 

 be water, not merely because of its colour, but 

 from the fact that it polarizes light. More- 

 over, it must be fresh water, since it is derived 

 from the melting of the ice which is formed by 

 the successive precipitation of heavy rime during 

 winter. This belt of water, some 300 miles broad, 

 closely follows on the shrinking ice-cap, and finally 

 gives way in its turn to yellow land. The natural 

 inference is that the water must be drawn off from 

 the pole towards the equator. This inference is 

 borne out by the fact that soon after the ice-cap 

 begins to melt the " canals " and oases come 

 annually into visibility, each in the place occupied 

 in previous summers, and grow more and more 

 conspicuous. The distinctness of detail sweeps 

 gradually over the surface of Mars from pole to 

 equator, during the summer ; the oases appear 

 very shortly after the "canals" become visible, 

 and increase in depth of tint. This curious wave 

 of growth is probably to be explained by the 

 fact that the fresh water derived from the annual 

 melting of the ice-cap is carried by irrigation- 

 canals into the equatorial deserts ; that, owing to the 

 water thus conveyed, vegetation is able to grow- 

 along each canal so as to form a zone fifteen to 

 thirty miles broad, and that each oasis, being at 

 the intersection of two or more "canals," is more 

 richly supplied with water and hence can extend 



further into the desert. It should be noticed, 



moreover, that the size of an oasis seems to be in 



direct proportion to the number of " canals " 



passing through it. 



The longer the surface- features of Mars are 



studied, the more irresistible is the conclusion that 



these " canals " and oases are the outcome of an 



intelligent design, contrived for the purpose of 



cultivation in order to meet the difficulties caused 



by an increasing dearth of water. We can well 



imagine that the date when the polar ice-cap first 



begins to melt is an anniversary of far more 



anxious importance in Mars than the rise of the 



Nile in Egypt or the arrival of the monsoon in 



India. We have of course, no reason to suppose 



that the inhabitants of Mars resemble us, or 



anything else on this world of ours. In the first 



place, they must be creatures capable of existing 



in a highly rarefied atmosphere, and the possibilities 



of life under physical conditions so different to 



ours are almost beyond the reach of imagination. 



There is no need, however, to predicate anything 



excessive in the size of the beings who have executed 



such stupendous irrigation-works, for, owing to 



gravity being less, a human being if placed on Mars 



would be capable of doing about three times as 



much work with the same effort which he would 



exert on our globe. The triangulation of the 



whole surface by irrigation-canals, traversing alike 



the deserts and the areas of permanent vegetation, 



pre-supposes, however, not only a knowledge of 



mathematics, engineering and agriculture, but 



clearly indicates that the Martian population has 



reached a high ideal of communism and political 



unity from which we are still far removed. The 



very flatness of the surface may have largely 



brought about this happy result in rendering 



communication easier by the cutting of canals 



for over 3,000 miles in a direct ine. Moreover, 



the absence of any physical barriers, such as 



rivers and mountain-ranges, will have prevented: 



that development of distinct nations and races-, 



differing in language, customs and aspirations,. 



which is so characteristic of our continents. 



49, Blomfield Road, Maida Hill. London, W. 

 July, 1897. 



The Black Ahtocopyist. — We ave hrecently 

 seen some beautiful pictures and other work, 

 produced by this simple machine, and its ally, the 

 photo-autocopyist. In the hands of an amateur, 

 pictures of natural-history objects or other 

 drawings or photographs may be reproduced in 

 numbers, for circulation among correspondents. 

 To secretaries of scientific societies the machine is. 

 invaluable for sending out notices and reports, 

 maps for excursions, etc., because of the simplicity 

 and rapidity with which they can be produced- 

 Some of the specimens which have been submitted 

 to us are most artistic, and equal to first-class 

 collotype pictures. The price and further 

 particulars may be obtained from the Autocopyist 

 Company, 72, London Wall, E.C. 



