For the man in the cage, in turn, put out his hand and touched the glass opposite Van Emmon.  Then he opened his mouth.

“I am very glad to see you,” said he in a soft, pulsating voice—­and in the best of English.

IV

A PUZZLED WORLD

For a moment blank amazement gripped the four.  Then amazement gave way to genuine apprehension.  Were they insane to imagine that this man of another world had spoken to them in their own language?  Each looked at the other, and was astounded to see that all had heard the same thing.

Presently the stranger spoke again; if anything, the kindly smile on his face became even broader.  “Suppose we postpone explaining how I am able to use your tongue.  It will be easier for you to understand after you have been with us a while.”  He spoke slowly and carefully, yet with a faint lisp, much as some infant prodigy might speak.

But there was no doubt that he had really done it.  The doctor managed to clear his throat.

“You are right,” said he, with vastly less assurance than the amazing stranger.  “We will try to understand things in the order you think best to present them.  You—­should know best.”

Kinney introduced himself by name and profession, also the other three.  The stranger nodded affably to each.  “You may call me Estra,” said he, pronouncing it “Ethtra.”  “There is no occupation on the Earth corresponding with mine, but in my spare moments I am an astronomer like yourself.”

The doctor silently marveled.  He had not told the stranger about his hobby.  Meanwhile the architect attempted to break the ice even finer.

“We take it for granted,” said she rather nervously, “that your people are somewhat further advanced than us on the earth.  However, we expect to be given credit for having visited your planet before you visited ours!” She said this with an engaging smile which won an instant response; the Venusian’s lips almost lost their curves in his generous effort.

“You will find that we greatly respect all that you have accomplished,” he declared earnestly.  “As for your apparatus”—­glancing at the cube—­ “you have the advantage on the earth of certain chemical elements which are entirely lacking here, otherwise we should have called upon you long ago.”

He slipped a panel of glass to one side.  “Step in quickly!” he exclaimed, gasping; and the four obeyed him without thought.  It was only when the panel was replaced that they noticed the floor of the cage; it was of clear glass, like the sides, and looked totally incapable of bearing their combined weight.

The Venusian smiled at Smith’s worried look.  “The material is amply strong enough,” said he.  “I am only concerned about your machine there.  Is it safe to be left alone?”

“So far as we know, yes,” answered Van Emmon, who did not feel quite as much confidence in the stranger as the rest.