mproving his stroke with such energy,
and was in the tank so much, that before the end of his freshman year,
he was by long odds the best swimmer in the college. With his devotion
to fish and his prowess in the water, it was a common saying that
"Dare's growing fins!" and the college paper took to calling him "Fins,"
a nickname which stuck to him ever after.

As he had intimated to his father long before, Colin was especially
anxious to go to Woods Hole, the great marine station of the Bureau of
Fisheries, situated on the southwestern corner of Cape Cod, and the most
famous marine biological laboratory in the New World. The work of the
Fisheries appealed to him a great deal more when it bore a relation to
the sea, rather than to rivers and inland waters, and his application
for a position on the summer force at Woods Hole had been sent to
headquarters shortly after the New Year. Accordingly, just as soon as
the term was over, he hurried to Washington.

Disappointment awaited him. His heart had been set on that especial
feature of the work, but when he asked Dr. Crafts about it, the Deputy
Commissioner shook his head.

"I have thought the matter over," he said, "and if you are equally
anxious next year to go to Woods Hole you shall go. But this season I'm
going to send you to the Mississippi to do some work on mussels."

"Very well, sir," Colin answered, his expression betraying his regrets,
but his will determining that he would make no seeming complaint. "I
wish I'd known this winter, and I would have given more attention to the
mollusks."

The Deputy Commissioner, who had friends in Brown University, had heard
indirectly once or twice about Colin, and smiled to himself. He was
pleased by the lad's self-control, and continued:

"The mussel question is of a great deal more interest than you think.
I'm not sure, of course, but there are signs of a pearl-fever, and if
there is one, you'll certainly see something doing. The Mississippi and
Ohio were like a Klondike in 1903!"

"What is a 'pearl-fever,' Dr. Crafts?" asked the boy.

"A silly infatuation that seems to strike the farmers of the river
valleys every few years on hearing that a valuable pearl has been found
in a mussel. The get-rich-quick hope is very general, and it seems so
much easier to dredge mussels and open them until a fortune is found in
one than it does to farm for a living. In 1903, thousands upon thousands
of farms were deserted or sold for ne