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 142,000,000 miles. Even from our own world we can discern through a good telescope the changing colors of the planet, due to the recurring seasons, each one of which is almost twice the length of ours.

There is relatively much less water on Mars than is found on our Earth, and gravity on its surface is only thirty-eight per cent of terrestrial gravity. Imagine, then, how light everything must be. This may account somewhat for the physical proportions of its inhabitants, for they are over twice our size, and in appearance resemble us but little. They have four arms, two extra ones extending from a point just above the knees. The two lower arms act as servants to the two higher. Thus are the four used at one time in harmony.

Mars is an older world than ours, and although it receives only one-half as much heat from the sun yet it is almost of the same temperature, owing to a peculiar condition of the atmosphere which we would call "heat retentivity."

Some scientists and philosophers will at once say that such atmospheric conditions are