back of the fort another
"cannon ball" came sailing into it, flying off and hitting Laddie's
brother.

"Ouch! Quit that!" cried Russ. "'Tisn't fair throwing sand! A lot of it
went down my neck."

"I didn't throw sand!" said Laddie.

"Yes, you did, too! That last cannon ball you threw had a lot of sand
wrapped up in it."

"No, I didn't," cried Laddie.

"Don't you think I know!" shouted Russ, scrambling up out of the hole
behind his fort. "Can't I feel it?"

Just then another paper "cannon ball" sailed into the fort from a sand
hill back of it and it fell at the feet of Russ and burst, letting out a
pile of sand.

"There!" cried Russ. "What'd I tell you?"

"But I didn't throw it!" said Laddie. "You looked right at me and I
didn't throw it."

"No, you didn't," admitted Russ. "It came from in back of me. I wonder
who's throwing sand cannon balls at us."

And then came another which hit Laddie, sending a shower of the gritty
grains down his back.

"Hi! Quit that!" cried Russ. He and Laddie looked all around, but they
could see no one. A mysterious enemy was shooting at them.

CHAPTER XXV

THE TREASURE

Once more there came sailing through the air a paper "cannon ball." It
fell on the ground between Laddie and Russ and burst open, a lot of dry,
soft sand spilling out.

"There!" cried Laddie. "See! I didn't throw 'em!"

"No, I don't guess you did," admitted Russ. "But who did?"

Just then a jolly laugh sounded, and out from behind a ridge of
sand--one of the dunes made by the wind--came George Carr.

"Did I scare you?" asked George.

"A--a little," admitted Russ, wiggling to get rid of the sand down his
back.

"We didn't know who it was," said Laddie. And he, too, squirmed about,
for there was sand inside his blouse.

"I thought you wouldn't," said George, laughing again. "I saw you
playing soldiers and I thought I'd make believe I was another enemy
coming up behind. You didn't make any fort in back of you," he said to
Russ, "and so I could easily fire at you."

"But we don't put sand in our paper bullets," complained Laddie.

"Don't you?" asked George. "Then I'm sorry I did. I hope I didn't hurt
you, or get any in your eyes."

"No," answered Russ, sort of shaking himself to let the sand sift down
through the legs of his knickerbockers. "But it tickles a lot."

"Well, I won't throw any more," promised George. "But lots of times we
play soldier down on the beach and we throw sand bulle