f the men who
climbed the slope at the front and, ignoring the main entrance, passed on
to the second floor by a secret staircase in the wall, entrance to which
seemed easy for them to find.

At the hour named three acquaintances of the reader occupied the front
room on the second floor of the stone house. They were Col. Van Ellis, the
military man Frank Shaw had talked with in the old house near the Culebra
cut, Harvey Chester, the father of the boy Jimmie and Peter had
encountered in the jungle, and Gostel, the man who had approached the two
boys the night before on the lip of the great excavation.

In a rear apartment, a sort of lumber-room, devoted now to wornout and
broken furniture and odds and ends of house furnishing goods, was still
another acquaintance--Ned Nestor. The patrol leader had met the two lost
boys at Culebra, in the company of Harvey Chester and his son, Tony, and
had spent enough time with the party to learn that Pedro, the ex-servant
of the Shaw home, had been seen at the Chester camp, and that he had fled
at the approach of Jimmie and his chum.

The story of Gostel's watching the cut at night, probably assisted by
Pedro, and Harvey Chester standing guard, or seeming to do so, by day, had
interested Ned greatly. The presence on the Isthmus of Pedro gave an extra
kink to the problem. The attempt to capture the two boys, as previously
told by Gastong, on the previous night, and the unmistakable anxiety of
Chester to remain in their company, had led Ned to believe that at last he
was getting to some of the people "high up" in the conspiracy against the
canal. Surely a man of the education and evident wealth of Harvey Chester
was not loitering along the Culebra cut just for the excitement there was
in it. It was plain that he was there for a purpose, and the arrival of a
man Jimmie declared to be Gostel had convinced Ned that the heads of the
plot were not far away.

Gostel had greeted the boys heartily, expressing relief at the knowledge
that they had escaped in safety from the jungle, and Chester had urged
them all to accept of his continued hospitality. Nothing had been said of
Gostel's pursuit of the two boys, and Ned had reached the conclusion that
Gostel did not know that his movements had been observed.

Anxious to see what Gostel really was up to, Ned had instructed the boys
to remain at a hotel at Culebra or visit the Chester camp, just as they
saw fit, and had followed Gostel back to Gam