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94 conform as near as might be to the actual look of the planet. To photograph minute planetary markings directly is, for reasons too long to state here, impossible. The views give between them the whole surface of the planet shown us at what corresponds to our first of August. Thus, neither the polar cap nor the polar sea appear in the pictures, for both had then disappeared. Nor do the southern parts of the so called straits show, for a similar reason. But from a knowledge of the features here presented the reader will find interpolation of any others referred to easy.

Previous to the present chart, the most detailed map of the planet was Schiaparelli's, made in 1888. On comparison with his, it will be seen that the present one substantially confirms all his detail, and adds to it about as much more. I have adopted his nomenclature, and in the naming of the newly found features have selected names conformable to his scheme, which commends itself both on practical and on poetic grounds.

We will begin our journey at the origin of Martian longitudes and travel west, taking the points of the compass as they would appear were we standing upon the planet. As all astronomical pictures are, for optical reasons, upside down, south lies at the top of the pictures, west to the right, north at the bottom,