As Radford was but four miles distant from the post the trip was not to be a long one.

“This is the sort of job that has me by the ears,” glowed Eph Somers, enthusiastically.  “I won’t be selfish enough to say I hope to be the fellow to catch Millard.  But, if he does stray my way, I hope I won’t be idiot enough to let him slip through my fingers.”

“I don’t care if Lieutenant Ridder is the one who nabs him,” remarked Hal, coolly.  “All that I’m particular about is to see this foreign agent nabbed before he succeeds in getting any information out of the country.”

The car that bore the boys was soon driving through the streets of Radford.  Jack held in his hand a list of the better grade and middle-class hotels that Colonel Totten had given him.

“Which hotel are we going to first?” asked Hal.

“I don’t know,” uttered Jack, suddenly, sharply.  “I know what I’m going to do, however.”

Leaning slightly forward the young submarine captain prodded the chauffeur lightly, twice, in the back—­a signal that had been agreed upon at need.

In response, the chauffeur ran the car slowly in at the curb.

Captain Jack, opening the tonneau door, was quickly out on the sidewalk, without any need having risen for wholly stopping the car, which then shot forward again.

“Now, what on earth was that for?” demanded Eph Somers, as the car sped on.

“Don’t look back,” replied Hal.

“Why not?”

“Well, a certain party would see you looking at him.”

“Who?”

“Why, Jack had the good luck to see Millard going along on the sidewalk.  We’ve just passed the fellow!”

“Are we going to nab him?” demanded Somers, breathlessly.

“You’ll have to leave that decision to good old Jack,” chuckled Hal
Hastings.  “He’s out there, dogging Millard from the rear.  It’s Jack
Benson’s affair just at this moment.”

It was mighty hard for Eph to refrain from looking back.  But he restrained his curiosity.

CHAPTER VI

FLANK MOVEMENT AND REAR ATTACK

When Jack Benson first touched the sidewalk, and the automobile glided on, leaving him in the wake of Millard, it was the young submarine captain’s intention to follow his instructions to the letter.

Millard, having no especial reason of his own for feeling in danger, was walking along at a moderate gait, occasionally glancing into shop windows or gazing at the people whom he passed.

He did not look behind, so it was easy for Jack, less than half a block to the rear, and keeping close to the buildings, to follow without being detected.

“Hullo,” muttered the submarine boy.  “There’s a policeman on the crossing at the next corner.  In another moment our long-legged one will be safely in custody.”

Feeling in his inner coat pocket for the written authorization, Benson’s fingers touched the envelope.