This upset every idea they had had; it never occurred to any of them that the planet could revolve at such speed that it would appear stationary.  Smith went at once to the eastern window and watched closely, for fear some irregularity in that apparently perfect sphere might catch them unawares.  They did not learn till later that Venus’s day is a little less than twenty-five hours, and therefore, since they had approached her near the equator, the wind they had encountered was moving at nearly nine hundred miles per hour!

Bit by bit, though, the cube answered to the wind-pressure.  Soon they noted the sun rising slowly; and by the time it was two hours high the surface, which had been whizzing under them like some highly polished top, became entirely motionless:  The cube had “stopped.”

One minute later the car touched the level.  Smith very slowly reduced the repelling current so that the immense weight of the cube was but gradually shifted to the unknown surface beneath.  Ton after ton was added until—­

“Stop!” came from the doctor.  He had noted through the window a slight curvature in the material.

So the machinery was left in action.  “At any rate,” said Smith, “we know that the confounded stuff isn’t antimagnetic, whatever it is.”  Of course this was true—­even though the gelatinlike shell could not support the cube’s weight, yet it did not insulate the planet from the repelling current.

The thermometer registered three hundred and thirty-five degrees Fahrenheit.  “Two hundred and eighty degrees higher than it would be at home in the same latitude,” remarked the doctor.  “We’ll have to use the suits.”  He took it for granted that exploration should begin at once.

No one stayed behind.  The machines could be relied upon, as they knew from nearly two weeks of use, and certainly there was nothing in sight which could possibly interfere with the cube.  Nevertheless, the matter-of-fact engineer took care to remove part of the door-operating apparatus when he left the vestibule, and nobody commented upon it.  It seemed the sensible thing to do; that was all.

There was just about enough additional weight in their suits to balance the slightly reduced gravitation, so they moved about, four misshapen, metallic hulks, with as much freedom as though back home.  Always they kept within a few feet of each other so as to throw no strain on their interconnecting telephone wires.  The big, glass-faced helmets gave a remarkable sense of security.

They made a complete circuit of the cube, and at the end of it looked at each other in perplexity.  Never, save in the middle of an ocean, in the doldrums, did any man ever see such a totally barren spot.  Not a tree, much less a sign of human occupation; there was not even the slightest mound.  The planet was, in actual fact, as smooth and as bare as a billiard ball!

Moreover, the surface itself remained as mysterious as before.  Of course they did not touch it with bare hands—­all wore insulated mittens—­but the dazzling stuff was certainly as hard as steel and as highly polished.  It was neither transparent nor opaque, but translucent, “like pink mother-of-pearl,” as Billie suggested.