its surface, for high air currents on the light torrid side probably flow rapidly to the dark, cold side, with the cold air near the surface of the dark, cold side flowing with equal rapidity to the torrid side. This state of affairs may tend to equalize the intensity of the two extremes of climate. Being almost 30 million miles closer to the sun than the earth, Venus may have a higher temperature than the earth, although the heat may be somewhat modified by the clouds which are always in the sky.
Sometimes a faint, grayish light has been observed on the dark side of the planet when it is nearest the earth. This was at one time thought to be a reflection from a cold and frozen hemisphere, but a more likely suggestion hints that it may be an electrical manifestation in the planet's atmosphere, similar to our Aurora.
Venus completes its orbit in 7½ months, its year being rather shorter than ours.
The question of the existence of life not only on Venus, but on the other planets, is always a subject of general interest. Professor Barnard of the Yerkes Observatory had the following convictions on the subject:
"There are possibilities of life on some of our brother worlds, though that is not in any way a necessity, possibly on Mars and probably on Venus, with Mercury very doubtful but more probably lifeless. The moon we will not consider, for we believe that it is dead long ago—even if it ever had any form of life upon it. It may even be that some world of our solar system has ceased to bear life and it has been suggested that possibly Mars is such a world. This is in no wise unreasonable. It is entirely probable that some of them are not in a life-bearing condition, just as a tree in your orchard may not have obtained maturity yet. Their heyday is yet to come, perhaps this will be when the earth and all its present life are cold and dead—dead of old age! for a world must die just as a man must die."
Jupiter, Saturn, Uranus and Neptune are considered, he says, to be worlds of the future, their low density and other considerations leaving little doubt of their unripeness for life. Perhaps millions
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