"Mr. Slipher, who accompanied Professor Todd's expedition to Alianza in Chili, at the opposition of 1907, together with the observers at Flagstaff, discovered no less than 85 new canals, including some doubles, nearly all being in the more southern portions of the southern hemisphere. "In addition to the discovery of so many fine lines, we also owe to the acumen of Professor Lowell a reasonable explanation of what they really are. Schiaparelli termed them 'canali,' an Italian term for 'channels,' but, popularly, this soon became corrupted into the term 'canals,' and this has turned out to be a much more appropriate word than such corruptions usually are. [Illustration: _From a Globe made by M. Wicks_ Plate IX MARS. MAP II The Solis Lacus is seen as an oval patch near the top, and many long canals, some double, are shown. A very large proportion of the area on this map is desert land.] CHAPTER XI THE GREAT MARTIAN CONTROVERSY (_continued_) "As the result of very long continued and systematic observation of the lines on Mars, together with carefully plotting them down on a globe, it was found that every line was continuous, uniform in width, and went straight from one definite point to another, not one breaking off in open space. Moreover, on being tested, nearly all were found to be arcs of great circles, and therefore the shortest possible lines which could connect any two points on a sphere. This fact strongly supports the idea that they are not natural but artificial formations. For a long time the lines were only seen on the red, or lighter, parts of the planet, but in 1892 an expedition was sent from Harvard Observatory to Arequipa, in Peru, for the purpose of observing the planet under very favourable conditions, and this resulted in important discoveries. Professor W.H. Pickering, who accompanied the expedition, was fortunate enough to observe that the canal lines extended over the dark or blue-green portions of the disc; and later observations have proved that this is the case all over the planet, and the lines are visible from pole to pole. "These observations also led Professor Pickering to the important conclusion that all the dark areas were covered with vegetation, and that the bright or red areas were deserts, the colour of the latter being exactly that of our deserts when viewed from a great distance. Herschel's idea had been that the red areas were land covered with vegetation of a red colour, and that the dark areas were seas.