All hands ran down to the shore and looked off upon the water, but not a thing could they see of old P. D.

CHAPTER XI.
THE LETTER ON THE TABLE.

“He’s around here somewhere,” said Dick. “There’s no mistaking that melodious voice, but where?”

Suddenly another strange sound broke upon the air; half scream, half roar, and then a tremendous splash was heard over in the direction of the next cove.

The boys and Doctor Dan, seizing their rifles, ran that way, but before they got to the bend of the rocks they were able to see what was going on.

It was such a combat as probably no man on earth ever witnessed before.

There was old P. D. and a monster precisely similar to the one the boys had seen on the other side of the lake hard at it, and a bellowing and roaring broke upon the air that was fairly deafening.

The Plesiosaurus would rear its ugly head far above the water and strike with lightning rapidity at its antagonist, which would dodge and then dart forward, squirting up two vast streams of water out of holes in each side of its huge snout, snapping its crocodile-like jaws and displaying its terrible teeth.

For about twenty seconds the boys were treated to this wonderful exhibition and then, with a fearful splash, monster No. 2 leaped half its length out of the water, caught old P. D. by the neck and dragged him down out of sight.

“By gracious!” cried Charley. “That’s great!”