What, however, was beyond denial was, that if the polar ice and snow were not so purely and distinctly white as they appear at a distance upon Earth, they were yet to a great extent devoid of the yellow tinge that preponderated everywhere else.

The most that could be said was, that whereas on Earth the snow is of that white which we consider absolute, and call, as such, snow-white, but which really has in it a very slight preponderance of blue, upon Mars the polar caps are rather cream-white, or of that white, so common in our flowers, which has in it an equally slight tinge of yellow.

On the shore, or about twenty miles from the shore of the principal sea to the southward of the equator, and but a few degrees from the equator itself, I perceived at last a point which appeared peculiarly suitable for my descent.

A very long range of mountains, apparently having an average height of about 14,000 feet, with some peaks of probably twice or three times that altitude, stretched for several hundred miles along the coast, leaving, however, between it and the actual shore-line an alluvial plain of some twenty to fifty miles across.

At the extremity of this range, and quite detached from it, stood an isolated mountain of peculiar form, which, as I examined it through the telescope, appeared to present a surface sufficiently broken and sloped to permit of descent; while, at the same time, its height and the character of its summit satisfied me that no one was likely to inhabit it, and that though I might descend-it in a few hours, to ascend it on foot from the plain would be a day's journey.