equable southern England, and a disappearance of the vast snowfields of its polar regions as rapid and complete as what occurs with us! If the moon, even at its equator, has not its temperature raised above the freezing-point of water, how can the more distant Mars, with its oblique noon-day sun falling upon the snow-caps, receive heat enough, first to raise their temperature to 32°F., and then to melt with marked rapidity the vast frozen plains of its polar regions?
Mr. Lowell is however so regardless of the ordinary teachings of meteorological science that he actually accounts for the supposed mild climate of the polar regions of Mars by the absence of water on its surface and in its atmosphere. He concludes his fifth chapter with the following words: "Could our earth but get rid of its oceans, we too might have temperate regions stretching to the poles." Here he runs counter to two of the best-established laws of terrestrial climatology—the wonderful equalising effects of warm ocean-currents which are the chief agents in diminishing polar cold; the equally striking effects of warm moist winds derived from these oceans, and the great storehouse of heat we possess in our vapour-laden atmosphere, its vapour being primarily derived from these same oceans! But, in Mr. Lowell's opinion, all our meteorologists are quite mistaken. Our oceans are our great drawbacks. Only get rid of them and we should enjoy the exquisite climate of Mars—with its absence