During the last few years the public mind has been unusually exercised over Mars, largely by reason of a misapprehension of the terms employed in the discussion about his physical features. The talk of 'canals' has suggested human, or at all events intelligent, agency, and the expectation arose that it might not be quite impossible to establish communication between our world and its nearest neighbour on the further side. The idea is, of course, only an old one furbished up again, for early in last century it was suggested that a huge triangle or ellipse should be erected on the Siberian steppes to show the Lunarians or the Martians that we were intelligent creatures who knew geometry. In these circumstances curiosity was whetted by the announcement, first made in 1890, and since frequently repeated, of the appearance of bright projections on the terminator of Mars. These were construed, by people with vivid imaginations, as signals from the Martians to us; while a popular novelist suggested a more sinister interpretation, and harrowed our feelings with weird descriptions of the invasion of our world by Martian beings of uncouth appearance and superhuman intelligence, who were shot to our globe by an immense gun whose flashes occasioned the bright projections seen. The projections were, however, prosaically referred by Campbell to snow-covered mountains, while Lowell believed that one very large one observed at Flagstaff in May, 1903, was due to sunlight striking on a great cloud, not of water-vapour, but of dust. As a matter of fact, Mars is somewhat disappointing to those who approach the study of his surface with the hope of finding traces of anything which might favour the idea of human habitation. He presents an apparently enticing general resemblance to the earth, with his polar caps and his bright and dark markings; and his curious network of canals may suggest intelligent agency. But the resemblances are not nearly so striking when examined in detail. The polar caps are the only features that seem to hold their own beside their terrestrial analogues, and even their resemblance is not unquestioned; the dark areas, so long thought to be seas, are now proved to be certainly not seas, whatever else they may be; and the canal system presents nothing but the name of similarity to anything that we know upon earth. It is quite probable that were Mars to come as near to us as our own moon, the fancied resemblances would disappear almost entirely, and we should find that the red planet is only another instance of the infinite variety which seems to prevail among celestial bodies. That being so, it need scarcely be remarked that any talk about Martian inhabitants is, to say the least of it, premature. There may be such creatures, and they may be anything you like to imagine. There is no restraint upon the fancy, for no one knows anything about them, and no one is in the least likely to know anything.