Though Reade remained up until broad daylight no further sign of the unknown enemies was seen.  Through the night, had it not been for the patrols walking up and down the line of wall with lanterns, it would have been hard to realize that the big breakwater was haunted by any such desperately practical group of “ghosts.”

“I guess we’ve heard the last of the rascals,” suggested Harry Hazelton one night at supper.  Messrs. Bascomb and Prenter had returned to Mobile, so that the young engineers and their superintendent were the only men at table.

“My guess is about the same,” drawled Mr. Renshaw.

“Yes?” queried Reade.  “Guess again!”

“Oh, I believe they’ve quit,” argued Mr. Renshaw.  “For one thing, the scoundrels probably have discovered that detectives from Mobile are down here trying to run ’em to earth.  That has scared the rascals away.”

“What are the detectives doing, anyway?” asked Harry.

“Blessed if I know,” Tom yawned.  “I believe there are three of them here or over in Blixton, but I wouldn’t know one of them, if I fell over him.  The detectives came, secured their orders from Mr. Prenter, and went to work—–­or pretended to go to work.  I’m glad that I’m not responsible for the detectives.”

Nicolas entered, an envelope in his hand.

“Par-rdon, Senor Reade,” begged the Mexican.  “I would not interrupt, but on the porch I found thees letter.  It is address to you.”

Tom took the envelope and scanned it, saying: 

“The address is printed—–­probably because the writer didn’t want to run the risk of having his writing identified.  Probably the letter, also, is printed.  Pardon me, gentlemen, while I open this communication . . .  Yes; the letter is printed, and unsigned—–­a further sign of cowardice on the part of the writer.  And now let me see what it says.”

Tom spent a few moments in going through the communication.  A white line formed around his mouth as he read.  Then he passed the letter to Harry, who read it aloud, as follows: 

"You have had a week of peace.  Is peace better than war?  You may have all the peace you wish, and go on working and prospering if you will let others do the same.  Stop interfering with the right of your men to amuse themselves and all will be well.  Try any of your former tricks in the camp, and then you will have good cause to ‘Beware!’"

“Is that a declaration of war?” asked Harry, looking up.

“I think so,” nodded Tom.

“Then how are you going to meet it?”

“There’s only one way,” Tom returned.  “A declaration of war must be met with a fight.  Unless I’m very greatly in error the gamblers and bootleggers will try to start up matters again to-night in camp.”

“And you’ll throw them down harder than before?” queried Mr. Renshaw, gazing keenly at the young chief.

“If it be possible,” Tom declared.  “Nicolas, be kind enough to go over and ask the foremen to report here at 8:20 promptly.  At 8:30 we will enter camp and see what is going on.”