His daughter's exasperation now mildly amused Big Eric. He went on, then, explaining his purpose in seeking out Doc Savage in their trouble.

"Perhaps neither Ham nor Doc could help us against the Gray Spider, but Doc and Ham and the rest of their pals can help us, I'm sure!"

"You see, it's not Doc alone, though Doc is the mainspring and regulator of the group. There are five of them, besides Doc. They're all men who are experts in their respective lines, and all of them owe so much to Doc—even their lives—that they will do anything for him. Not only that, but his knowledge is so great that he is the one person to whom all must bow.

"And I know they'll help us, because that's their work; their lives are devoted to the task of smashing those who plot evil, of helping those who need help. They want excitement; they yearn for adventure; they live on thrills! They're real men—and it will take real men to get the Gray Spider!"

Father and daughter now fell silent. Discussing the power and mastery of the mighty Doc Savage had renewed the courage of both. They stared steadily beyond the nose of the speeding plane. In that direction lay the city of New York.

There in the metropolis, they hoped to find their salvation—Doc Savage.

THE assistant pilot was speaking again into the radio-telephone transmitter. "All going O.K.," he intoned calmly. "Looks like a perfect trip."

He was wrong.

There came a sudden, terrific explosion. It was within the washroom at the rear of the plane. The washroom door popped off its hinges. It flew the length of the cabin. A great tongue of scorching flame seemed to pursue it.

Sheets of the thin metal skin of the plane were ripped from the rear of the fuselage by the blast. Windows burst outward. Acrid smoke boiled in the cabin.

Miraculously, no one aboard the plane was killed, but the ship began to flounder crazily. The tail structure had been nearly torn off. Controls were severed. The craft was helpless as a bird with a broken back.

The pilot and his assistant seemed stunned with surprise. There had been no fuel tank in the rear of the plane. No part of the regular equipment could possibly have caused the explosion.

"Dad!" exclaimed Edna Danielsen. "That slick-haired man went into the washroom a few minutes ago! Remember?"

"Sure, I remember!" rumbled Big Eric. "The dirty rat! He lit the time fuse of a bomb and left it in there, if my guess is right!"

The plane careened more crazily. The mangled air liner was going to crash! The altimeter in the pilot's compartment read ten thousand feet. It was indeed fortunate the plane had been flying so high. There would be precious minutes in which to escape.

This air line was one which equipped their planes with a parachute for each passenger! The packs and the quick-attaching harness were in baskets above the seats. One 'chute to each passenger, but no spares!

The pilot and his assistant still seemed paralyzed with surprise.

Big Eric showed the stuff that had taken him from a lowly sawmill worker to the heights. He assumed charge.

"Put on your parachutes!" he boomed commandingly. "You will find them in the baskets over your seats! Then jump! One at a time! Quickly!"

A fat lady promptly screamed.

"Be calm!" urged Big Eric. "There's nothing to be scared of!"

But pandemonium seized the dazed passengers. Parachute jumping might hold no terrors for Big Eric and his blond, beautiful daughter, who stood so staunchly at his back. But to the others it smacked of the next thing to suicide. Another woman screeched. Men bellowed senseless words at each other in their fear.

Big Eric caught sight of the slick-haired man. The evil-faced fellow had been crouching from view behind a seat. But now the plane door opened.

The man leaped through into space. He had donned a parachute before the explosion!

This proved to Big Eric that the man had set the bomb. The fellow was one of the Gray Spider's minions!

BIG ERIC stood in the center of the plane cabin, and used his vast voice and powerful arms to quell the excitement. He knew how to handle panic-stricken crowds. He had learned that trick in many a sawmill disaster.

"Cut out the fool screeching and jump!" he roared. "Pull the ripcord ring of your parachute when you're clear of the plane!"

Big Eric's brain was racing. Why had the Gray Spider's man set the bomb—if the fellow was really one of the sinister gang? How could it be an attempt on the life of Big Eric and his daughter? The other passengers seemed in as much danger.

The torn plane was falling faster. Air was roaring through the rent portion of the fuselage. The earth was swelling upward like the green and bloated paunch of a vast monster.

In faltering succession, the passengers pitched through the plane door. The faces of some held white terror as they jumped. A few were grimly composed. Others sobbed belated prayers.

The pilot and his assistant had awakened to their sense of responsibility. They were left alone with Big Eric and his daughter.

"Jump!" the pilot shouted. "We shall go last!"

Big Eric understood. No doubt the pilot and his assistant felt bad because they had not been first to rise to the emergency and take charge of the passengers. They would feel better were they the last to quit the fast-falling plane.

Swiftly, Big Eric swung for the door. Other passengers were safe.

With a lunge, his daughter got in his path. Her horrified look brought the big lumberman up short.

"What's wrong?" he demanded.

"If this is an attempt on our life—our parachutes must have been tampered with!" gasped the girl.

A sharp rumble came out of Big Eric's chest. Wrenching his 'chute pack around, he tore open the brown canvas covering. He stared at the silk folds of the 'chute itself.

"Look!" he bellowed.

A powerful acid had been poured into the parachute pack. The stuff had destroyed the strength of the silk.

A quick examination was made of Edna's 'chute. They found the same condition.

Big Eric swallowed rapidly. The nimble thinking of his attractive daughter had saved both their lives. To have jumped with those mutilated 'chutes would have been certain death.

The pilot and his assistant came forward with an offer that redeemed their earlier failing.

"Our packs are O.K.! Two of us will jump with each 'chute!"

THE huge, mangled air liner had paused at about four thousand feet as though to chase its own broken tail about. But now it careened downward in a steeper plunge than ever.

The pilot hastily wedged pretty Edna Danielsen into his own 'chute harness. The two of them leaped bravely through the plane door.

There was no time for Big Eric to note whether the two had made the jump safely. Seizing the assistant pilot, Big Eric sprang clear of the plane. He was trusting his work-hardened muscles, now wrapped around the other man's body, to withstand the shock of the opening 'chute.

When they had tumbled well clear of the plane, the assistant pilot gave the ripcord a yank. With a swish like a large bird spreading its wings, the silken folds poured out. A shock followed that seemed to draw Big Eric's arms an inch apart at the joints. Then they floated in the air.

Big Eric glanced about. He emitted a bellow of rage.

The slick-haired man had landed and cast free of his 'chute harness. The fellow had dashed to a near-by highway. He was stopping a motorist, using a pistol for the purpose.

Big Eric dug his automatic out of his coat pocket, twisting one arm around for a firmer hold. It vomited a deafening pow, pow, pow!But the distance was too great. He saw the bullets spade up dust far wide of the target. He stopped shooting, not wanting to hit the innocent motorist.