“Nissr Arrib ela Sema.”

“Come again, sir?”

“Eagle of the Sky, in Arabic.  I suppose we’ll have to cut that down to Nissr, for everyday use.  But at any rate, our craft is christened.  Well, now—­”

He settled himself in the pilot’s seat, reached forward and drew toward him a shining metal shaft.  Four stout spokes unfolded; and from these, quadrants of a rim that easily snapped together.  The Master laid one hand easily on the rim of the big steering-wheel, flung his cap upon a locker, pulled down the telephone headpiece and snapped it on.

He touched a button.  The light died in the pilot-house, leaving only the hooded glows of the dials, switches, and small levers.  Night seemed suddenly to close in about the vast machine.  Till now it had been forgotten, ignored.  But as darkness fingered at the panes, something of the vastness of sky and air made itself realized; something of the illimitable scope of this adventuring.

Bohannan slid the window shut and settled himself beside Captain Alden.  He glanced at his wrist-watch, and a thrill of nervous exultation stabbed him.

“Only two minutes and six seconds more!” he murmured, gnawing at his mustache and blinking with excitement.  Alden remained calm, impassive as the Master himself, who now, pressing another button, sent a beam of wonderful, white light lancing through the darkness.

Track, buildings, trees all leaped into vivid relief as he tested the searchlight control.  He shot the beam up, up, till it lost itself, vaguely, in mist and cloud; then flung it even across the river, where it picked out buildings with startling detail.

He turned it, finally, square down the launching-way, through the yawning gates where the track abruptly ended at the brow of the Palisades—­the empty chasm where, if all went right and no mistake had been made in build, engine-power, or control, the initial leap of Nissr Arrib ela Sema was to be made.

Came a moment’s wait.  Faintly the pulsing of the engines trembled the fabric of Nissr.  Finely balanced as they were, they still communicated some slight vibration to the ship.  The Master snicked the switch of the magnetic-anchor release; and now the last bond that held Nissr to her cradle was broken.  As soon as the air-skid currents should be set going, she would be ready for her flight.

This moment was not long in coming.  Another turn of a switch, and all at once, far below, a faint, continuous hissing made itself audible.  Compressed air, forced through thousands of holes at the bottom of the floats, was interposing a gaseous cushion between those floats and the track, just as it could do between them and the earth wherever Nissr should alight.

Suspended thus on a thin layer of air, perhaps no more than a sixteenth of an inch thick but infinitely less friction-producing than the finest ball-bearing wheels and quite incapable of being broken, the ship now waited only the application of the power in her vast propellers.