At this time (1894) it began to be doubted whether there were any seas at all on Mars. Professor Pickering thought they were far more limited in size than had been supposed, and even might not exist as true seas. Professor Barnard, with the Lick thirty-six inch telescope, discerned an astonishing wealth of detail on the surface of Mars, so intricate, minute, and abundant, that it baffled all attempts to delineate it; and these peculiarities were seen upon the supposed seas as well as on the land-surfaces. In fact, under the best conditions these 'seas' lost all trace of uniformity, their appearance being that of a mountainous country, broken by ridges, rifts, and canyons, seen from a great elevation. As we shall see later on these doubts soon became certainties, and it is now almost universally admitted that Mars possesses no permanent bodies of water. CHAPTER II. MR. PERCIVAL LOWELL'S DISCOVERIES AND THEORIES. _The Observatory in Arizona._ In 1894, after a careful search for the best atmospheric conditions, Mr. Lowell established his observatory near the town of Flagstaff in Arizona, in a very dry and uniform climate, and at an elevation of 7300 feet above the sea. He then possessed a fine equatorial telescope of 18 inches aperture and 26 feet focal length, besides two smaller ones, all of the best quality. To these he added in 1896 a telescope with 24 inch object glass, the last work of the celebrated firm of Alvan Clark & Sons, with which he has made his later discoveries. He thus became perhaps more favourably situated than any astronomer in the northern hemisphere, and during the last twelve years has made a specialty of the study of Mars, besides doing much valuable astronomical work on other planets. _Mr, Lowell's recent Books upon Mars._ In 1905 Mr. Lowell published an illustrated volume giving a full account of his observations of Mars from 1894 to 1903, chiefly for the use of astronomers; and he has now given us a popular volume summarising the whole of his work on the planet, and published both in America and England by the Macmillan Company. This very interesting volume is fully illustrated with twenty plates, four of them coloured, and more than forty figures in the text, showing the great variety of details from which the larger general maps have been constructed. _Non-natural Features of Mars._