with
him."

At that moment the bolts of the big door were shoved back and a man
looked out. Whistler Morgan did not know the manager of the munition
works by sight; but the guard at once said:

"Here's a boy to see you, Mr. Santley."

"What is your name, young man?" asked the manager, eying the boy with
interest.

Whistler told him.

"Dr. Morgan's son, from Seacove? Come in," and Whistler was ushered
inside and the heavy door was again barricaded.

"We have to keep locked up here like a fortress at night," said Mr.
Santley. "Come in and let me hear what you have to say, young man. What
do you know about Mr. Blake?"

"Did you know he had been out at sea on an oil tender to-day?" blurted
out Whistler. "She was chased by a submarine chaser, but the tender
escaped in the fog. Afterward she came into Rivermouth Harbor without
her cargo."

"What's this? What's this?" demanded Mr. Santley. "Why, that has nothing
to do with the factory."

They were in his private office. He stood with his hand upon Whistler's
shoulder and asked the boy sternly:

"What have you to tell me about Mr. Blake, anyway? I don't want to hear
a lot of inconsequential gossip. I am worried about the man."

"Yes, sir. So am I," declared Whistler very earnestly. "I've been
worried about him ever since the other day when we fellows were over
here trying to get some of the boys to enlist in the Navy."

"Ah, were you one of that crowd?" asked Mr. Santley.

"Yes, sir; and coming over here we saw that man Blake----"

He went on to tell the manager of the munition factory about how his
suspicions were aroused and about the water wheel he had found at the
foot of the dam, ending with a detailed account of the affair of the oil
tender.

Mr. Santley's face expressed nothing but lively curiosity.

"And to-day you saw him on a boat that you think is a feeder for German
submarines?" muttered the manager. "It is whispered that they are off
this coast."

"We overheard this Blake and a man who I'm sure is captain of that oil
boat talking in a restaurant to-night. They mentioned two-fifty which
I believe is the number of the submarine off this coast. They spoke as
though more were expected. The Germans are going to make a big drive on
our shipping over here."

"You may be right, boy," agreed Mr. Santley. "That man Blake--well, he
doesn't seem to be in Elmvale now."

"He came back on this evening's train," declared Whistler.

"Are you sure? I hav