CONTENTS
1 The Mysterious Strangers
2 Atomic Spy
3 Danger Signal
4 A Perilous Experiment
5 The Whispered Clue
6 Bronich Vanishes
7 A Bold Offer
8 A Threat of Revenge
9 Pursuit on the Lake
10 A Crucial Test
11 Sabotage!
12 A Flight to Alaska
13 Dog Trouble
14 A Call from Washington
15 Southward Ho!
16 Lost in the Blizzard
17 Blind Rescue
18 Sneak Raid
19 Disaster Strikes
20 A Whale Charges
21 A Hairbreadth Escape
22 Prisoner of War
23 Showdown Battle
24 A Volcanic Eruption
25 Molten Triumph
ILLUSTRATIONS
The tear-gas guns brought them out of the fortress It was too late-the damage was done!
“We’ve hit an aqueduct!” Tom shouted
Tom fought desperately, but resistance was futile They made a complete circuit of the grounds
The trap door opened freely in response to Tom’s push As they reached the scene, the helicopter hit the ground with a jarring impact Tom sprang over the gunwales into Landis’ craft The jolt caused the sled to turn over, throwing Bud against a tree trunk It was not long before a shower of sparks burst into view Bud shouted again and again, “You’ve done it, Tom! You’ve done it!”
CHAPTER 1
THE MYSTERIOUS STRANGERS
“Man, look at this earth blaster go to town!” yelled Bud Barclay from the cab of a big tractor trailer.
“Speed her up a bit!” urged Tom Swift as he jogged alongside it.
The blond, rangy young scientist and his husky, dark-haired pal were testing Tom’s latest invention-an atomic-powered earth-digging machine, mounted on a platform above the truck’s cab. Tom hoped to use his invention for road and bridge construction work and for drilling tunnels.