ded Jack; and when told, he looked grave.

"There may be something in this," he said slowly. "Suppose we go up to
the fifth floor and try to find out a little more."

"We might get caught," said Fred.

"I don't see how," went on the oldest Rover boy. "Martell doesn't
occupy the whole floor. He has the front offices only. There are
several other firms in the rear. We might be calling on them, you
know," and he winked.

The boys talked the matter over for a minute or so, and then, as an
elevator came down, they entered and got out at the fifth floor. The
little corridor here was empty, for which they were thankful.

"Of course there may not be a thing in this," announced Jack. "It may
be some ordinary business deal which is perfectly legitimate."

"Not by the way those two German-looking fellows talked," said Andy.
"I didn't like their looks at all. Unless I miss my guess, they are a
slick pair."

The two strangers had looked to be about forty years of age. Each was
tall and rather stout, with a clean-shaven, florid face and close-cut,
sandy hair. Their eyes had had a shifty snake-like look, and this it
was, as much as anything, which set Andy against them.

The doors to the Martell offices were two in number, one marked
"Private" and the other, "Entrance." The boys waited for a few
seconds, and then walked softly over to the latter door. They heard a
murmur of voices, but could not make out what was being said.

"Perhaps they are in the office marked 'Private,'" whispered Jack, and
tiptoed his way in that direction, followed by his cousins.

In front of the door to this office they could hear slightly better.
The murmur of voices was at times quite distinct, and they caught the
words: "Supplies," "Canned goods," "Immediate delivery," "Motor
trucks," "Machinery," "Cash payment," "Night work," and a number of
others. Then the murmur of voices grew a little more animated, and
finally they heard Nelson Martell exclaim: "I think we ought to have a
thousand dollars at least in advance!"

"Better make it two thousand," came from Slogwell Brown.

There was an exclamation from the strange men, and then the voices
sounded lower so that the Rovers could not hear what was being said.
Suddenly, however, one of the strangers cried out:

"Oh, I forgot! I have an important engagement in less than half an
hour. I must go at once."

"I guess it's time we got out of here!" exclaimed Jack, and started to
retreat, as did the