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88 angles to the first rift and debouching into it. Bright points continued to be seen at various points to the westward round the cap. They are marked by crosses on the chart. Throughout these days, the cap was wont to appear shaded upon the terminator side, as one might expect of a snow or ice slope. During June, also, the contour of the cap was apparently elliptical. But on June 25 Professor W. H. Pickering noted, for the first time, that it no longer looked so. The melting had resulted in making its asymmetry perceptible.

On July 1 our Martian polar expedition disclosed what used to be the supreme quest of earthly expeditions,—that dream of arctic explorers, an open polar sea. On that day Professor Pickering perceived, in the midst of the cap, in longitude 260° and latitude 80°, a sheet of water about 250 miles long by 150 broad. It was in fact the spreading of the first rift about midway across the cap, and lay not far from the geographical pole of the planet, though not, it is to be noticed, near the pole of cold for it lay on the further side of the geographical pole from it. There is a touch of the irony of fate in this detection of an open polar sea on Mars before explorers have succeeded in doing so on the Earth.

In addition to these rifts and other irregularities of melting, small detached bits of the