"Now I think we can go down," said Redgrave, when everything had been put in position as far as possible. "I wonder whether we shall find the atmosphere of Mars suitable for terrestrial lungs. It will be rather awkward if it isn't."

A very slight exertion of repulsive force was sufficient to detach the Astronef from the body of Phobos. She dropped rapidly towards the surface of the planet, and within three hours they saw the sunlight, for the first time since they had left the earth, shining through an unmistakable atmosphere, an atmosphere of a pale, rosy hue, instead of the azure of the earthly skies. An angular observation showed that they were within fifty miles of the surface of the undiscovered world.

"Well, we shall find air here of some sort, there's no doubt. We'll drop a bit further and then Andrew shall start the propellers. They'll very soon give us an idea of the density. Do you notice the change in the temperature? That's the diffused rays instead of the direct ones. Twenty miles! I think that will do. I'll stop her now and we'll prospect for a landing place."

He went down to apply the repulsive force directly to the surface of Mars, so as to check the descent, and then he put on his breathing-dress, went into the exit-chamber, closed one door behind him, opened the other and allowed it to fill with Martian air; then he shut it again, opened his visor and took a cautious breath.

It may, perhaps, have been the idea that he, the first of all the sons of Earth, was breathing the air of another world, or it might have been some property peculiar to the Martian atmosphere, but he immediately experienced a sensation such as usually follows the drinking of a glass of champagne. He took another breath, and another, then he opened the inner door and went back to the lower deck, saying to himself: "Well, the air's all right if it is a bit champagney; rich in oxygen, I suppose, with perhaps a trace of nitrous-oxide in it. Still, it's certainly breathable, and that's the principal thing."

"It's all right, dear," he said as he reached the upper deck where Zaidie was walking about round the sides of the glass dome gazing with all her eyes at the strange scene of mingled cloud and sea and land which spread for an immense distance on all sides of them. "I have breathed the air of Mars, and even at this height it is distinctly wholesome, though of course it's rather thin, and I had it mixed with some of our own atmosphere. Still I think it will agree all right with us lower down."

"Well, then," said Zaidie, "suppose we get below those clouds and see what there really is to be seen."

"As there's a fairly big problem to be solved shortly I'll see to the descent myself," he replied, going towards the stairway.

In a couple of minutes she saw the cloud-belt below them rising rapidly. When Redgrave returned the Astronef was plunging into a sea of rosy mist.

"The clouds of Mars!" she exclaimed. "Fancy a world with pink clouds! I wonder what there is on the other side."