Doc took the hand.

Big Eric had believed he owned a big, hard, powerful fist. But his hand was as a soft baby's in the case-hardened grip of Doc Savage.

Big Eric drew a long breath of awe. This bronze man possessed a strength that was unbelievable, even though one had seen the incredible sinews in his arms and hands.

"Where are Monk, Renny, Long Tom, and Johnny?" Doc asked Ham.

Doc Savage had named the other four members of his group of five friends and aids.

"They were to arrive in about an hour," replied Ham.

Doc Savage now moved to the window. He drew something from his pocket—something the others could not see. The bronze hand made rapid motions on the glass of the window.

Big Eric and Edna had no idea what Doc Savage was doing, but Ham knew.

Doc was writing a message on the window with a transparent substance. His communication would remain absolutely invisible until rays from an ultraviolet machine were turned on it. Then it would appear—brilliant, glowing with an uncanny light.

The secret message was:

Go to New Orleans at once and get in touch with me through the lumber company of Danielsen & Haas.

Doc did not sign it. There was no need. No other hand could have inscribed a script as minutely perfect and recognizable as his.

"Monk," Renny, "Long Tom," and Johnny, his four friends, would turn the ultra-violet light on the window and get the message.

"Come on!" Doc picked up the drugged prisoner as lightly as though he were an infant. "We're heading back for New Orleans."

DOC SAVAGE stood on the running board of the taxicab which carried them away from the towering white skyscraper. His presence outside the machine had a magical effect, causing policemen to open traffic for them.

The taxi ended its journey at an airport on the outskirts of New York City. The airport flunkies showed the great bronze man much attention. Mechanics scurried about.

A hangar door caved open.

"Golly!" ejaculated Big Eric, staring at the plane which was being rolled into view.

The craft was an airman's dream. It was an all-metal job, low-wing, streamlined to the height of aлronautical engineering. In the air, the landing gear could be retracted, making the ship little more than a flying wing. The three great radial motors were equipped with the latest design speed cowling.

"This is Doc's new ship," Ham told Big Eric and Edna. "He had another very like this, but it was destroyed in a terrible experience we went through in the South Seas. The present craft was delivered while Doc was away. This is the first time he has seen it."

The slick-haired prisoner approached mechanically at Doc's command. Doc told him to get in the plane, but the man did not have thinking ability enough to realize he must climb the small ladder which folded out of sight when the plane was flying. Doc lifted him in the craft as though he were a stupid puppy.

"Wouldn't it be quicker to take Monk, Renny, Long Tom, and Johnny along with us?" inquired Ham.

"It would," Doc replied. "But it is part of my plan that they should not be seen in our company in New Orleans."

Big Eric, overhearing this, was surprised. So the big bronze man already had a plan of operations! He was certainly losing no time.

Each minute in Doc Savage's presence was increasing Big Eric's respect for the prowess of the mighty bronze man.

Doc took his position at the plane controls. The motors started in quick succession.

Big Eric, noting the airport personnel standing around with open mouths, wondered what so interested them. Then he understood.

The plane motors were silenced! The sibilant swish of the propellers was the only sound. As Doc opened the throttle, this note became a terrific whine, like the noise of a great gale.

With a short run, the plane took the air. The landing wheels folded up. The ship sped like an arrow into the west.

Craning his neck, Big Eric got a glance at the air-speed indicator. His eyes popped. They were doing nearly two hundred and fifty miles an hour. Yet the motors were not straining.

"It don't take Doc long to go places," Ham grinned.

But even Ham would have been surprised to know Doc Savage had just finished a grueling flight of thousands of miles from his "Fortress of Solitude" far within the arctic. For the bronze giant showed no signs of fatigue.

Attractive Edna Danielsen had been strangely quiet the last half hour, but her eyes had followed Doc's every movement. She seemed to get a thrill out of merely watching the bronze man.

The big speed plane rushed through the night. Inside the sound-proofed cabin, only a steady, low moan told of their terrific momentum.

The prisoner lolled back in a seat. He slept. His mouth was wide open, revealing the gruesome insignia of the Cult of the Moccasin tattooed inside.

HARDLY five hours later, the plane sped across lower Mississippi. New Orleans was not far ahead. Not a cloud scummed the sky. The moon slanted bright beams against the plane.

Using the plane's radio telephone, Doc had kept in touch with various airport stations, obtaining weather information.

The remarkably bright moonlight enabled Doc to discover another plane flying some miles ahead. The craft was probably making a hundred and fifty miles an hour. But Doc's speed plane overhauled it as though it was standing still.

He altered his course slightly. The other plane also swung over.

"What do you make of that?" Ham growled. "Do you suppose the Gray Spider has sent that plane after us?"

"We'll soon see," Doc replied. "I have taken no particular pains to keep our coming secret. The Gray Spider might have heard me getting weather reports over the radio. He could use a directional radio loop and locate us."

Doc's ship held its course. The other craft drew closer. It was a high-wing monoplane, with a tube of a fuselage. As commercial jobs went, it was fast.

Suddenly the ship zoomed upward, as though to let Doc pass below.

"I guess it's just some plane making a night flight—"

Ham never completed his statement.

With an abrupt dive, the other plane flashed in front of Doc's craft. At the same instant it released a tremendous gush of vile greenish vapor. The stuff spread rapidly.

"Poison gas!" bellowed the quick-thinking Ham.

Doc's speed plane could not swerve aside in time to avoid hitting the gas cloud. It had been released almost against the trio of flashing propellers.

Comely Edna Danielsen went white, and spread her hands over her face. Big Eric, a quick thinker himself, sucked in air to fill his lungs before the poisonous fumes came. The prisoner sat still, as unconcerned as a machine—for he couldn't think enough to realize there was danger.

The plane popped into the gas cloud. It came out. One minute passed. Two. The gas cloud was left nearly five miles behind.

Nothing had happened.

Doc banked the plane swiftly. He flung it for the craft which had tried to gas them.

"Hey!" puffed Big Eric, unable to hold his breath longer. "Ain't that gas gonna—"

"The plane cabin is airtight," Doc Savage pointed out. "Haven't you noticed you have experienced no difficulty in breathing during the flight, although we flew above twenty thousand feet much of the time? That was because the cabin is air-conditioned—furnished with oxygen stored in a special supply tank."

The gas plane was striving frantically for altitude, after the manner of combat craft. But it was like a clumsy buzzard fleeing from a speedy hawk. Doc's great racer came alongside. He saw the other pilot was wearing radio earphones.