“Then we can go down at once.”  With these words the man in satin turned to a small black box in one wall of the elevator and touched a button. [Footnote:  For details of this and other matters of an electrical and mechanical nature, the technical reader is referred to Mr. Smith’s reports to the A. S. M. E.]

Instantly the car began to descend, at first slowly and then with swiftly increasing velocity.  By the time the explorers had accustomed their eyes to the sudden semi-darkness, the cage was dropping at such a speed that the air fairly sang past its sides.

Far overhead was a square, black shadow in the waxlike crust which they had left; it was the shadow of the cube.  All about them was a dimly lit network of braces, arches and semitransparent columns; to all appearances the system seemed to support the crust.  Billie whirled upon the Venusian: 

“I’ve got it now!  The whole globe is covered with glass!”

Estra smiled his approval.  “For thousands upon thousands of centuries, my friend.  The thing was done when our ancestors first suspected that our planet was doomed to come so near the sun.  It was the only way we could protect ourselves from the heat.”

“Great!” exploded the doctor, admiration overcoming regret that he had not thought of it himself.  But Smith had other thoughts: 

“How long did it take to finish the job?  And what did it cost?”

“Two centuries; and about twice the cost of your last war.  I need only suggest to you that we colored the material so as to reflect most of the heat.  That is why the material looks blue from below, although pink from above.”

“Say”—­from Billie—­“how long are we to keep on dropping like this?”

“We will arrive in a moment or two,” answered the smiling one.  “The roof is raised several miles above the sea-level in order to cover all the mountains.”

By this time the four were able to make out things pretty well.  They saw that the dimness was only relative; the Venusian world was actually as well lighted as any part of the earth on a cloudy day.  And they saw that they were descending in a locality of astonishing beauty.

The stranger halted the car so that they could inspect the scene as though from an airplane.  In no way did the landscape resemble that of the earth.  To begin with, pillars of huge dimensions were placed every quarter-mile or so; it was these that supported the intricate archwork above.  They were made of the same translucent stuff as the crust, but had a light topaz tint.  The Venusian said: 

“You will not need to be told that the science of metallurgy has advanced quite far with us.  All our metals can be made transparent, if we like; those pillars are colored variously in different regions so as to be clearly distinguishable and prevent collisions of flying apparatus.”

But Van Emmon and Billie were both more interested in what lay between the columns.  They scarcely noticed that there were no people in sight at the time.  The ground was covered with an indescribable wealth of color; and it was only by a close examination that the buildings could be distinguished as such.