LIST OF ILLUSTRATIONS

"The Professor was reading the scrap, and silently handed it to George"

"'We have probably found a pirate's lair, and here is the booty'"

"The Professor walked toward him and held out his hand"

"With a single stroke the body of the snake was severed above the last
coil"

LIST OF FIGURES

1. The Broken Yoke

2. Top View of Boat

3. Side View of Boat

4. Cross Section of Boat

5. Force of Momentum

6. Red Angel

7. The Color Spectrum

8. Reflection Angle

9. The Hidden Message

10. The First Gun

11. The Bullet

12. The Sea-going Boat

13. The Cave

14. The Slab Found in the Cave

15. Old Coins Found in Cave

16. Cane Crusher

17. A Magnet

18. Magnetic Induction

19. The Two Magnets

20. Making a Permanent Magnet

21. Illustrating Wind Pressure, 1

22. Illustrating Wind Pressure, 2

23. Mariner's Compass

24. Chart of the Voyage

25. The Charting Board

26. Guava

27. Coffee

28. Cream Separator

29. The Lion and Cubs

30. The Puma

31. The Acajou

THE MYSTERIES OF THE CAVERNS

CHAPTER I

MYSTERIOUS DISAPPEARANCE OF THE TEAM

The boys looked at the Professor in amazement. They were too much
excited and concerned at the new situation to be able to interpret what
the sudden disappearance of their team meant.

The Professor turned to the boys: "Are you sure the yaks were tied
before we left them?"

"I was particularly careful," answered Harry, "to tie both of them."

"I am pretty sure that both were securely fastened, and they were in
that condition when I came back the last time," was George's reply.

To understand the peculiar situation above referred to, it will be
necessary to go back and briefly relate some of the remarkable events
which had taken place in the lives of the three people concerned in this
history.

George Mayfield and Harry Crandall, together with a Professor, were
mates on a ship training school, which sailed from New York one year
before. A terrific explosion at sea cast them adrift in mid-Pacific
Ocean, and after five days of suffering they were cast ashore on an
apparently uncharted island, without any food, and entirely devoid of
any tools, implements or weapons.

Exercising the knowledge of the Professor, and the ingenuity of the
boys, they gradually dug from mother earth and from the rocks and trees
the articles necessary to sustain