Apparently the commander of the Glasgow, Captain Sawyer, had been informed that he was to be provided with an escort, for only the fluttering of a few signal flags from the Glasgow and from the motorboat Lion, which carried Lieutenant Commander Thompson, in charge of the mosquito fleet, betokened a greeting.

The Glasgow swept majestically past, not pausing in her stride.  From the decks hands were waved and handkerchiefs fluttered toward the little vessels below, the passengers aboard leaning over the rails and speculating idly upon their presence.

The two foremost motorboats were The Hawk and the Lion, commanded by Lieutenant Commander Thompson and Lord Hastings.  The others followed close behind.

Jack and Frank had watched all this maneuvering with great interest; and now that the flotilla, in perfect formation, was proceeding straight ahead, Frank turned to his commander with a question: 

“And about where do you expect to pick up the enemy, sir?” he asked.

“Hardly more than twenty miles out—­certainly not more than two hours,” was the reply.

The motorboats followed closely in the wake of the big steamship.  Although they were, of course, plainly visible from the steamer, and could possibly be seen from the sides, it was hoped that the enemies’ submarine would take a position directly in front of the Glasgow when she accosted her.  This would shield the motorboats from sight.

The Glasgow and its bodyguard were now out of sight of land.  The sun shone brightly and the day was perfectly calm.  There was scarcely a ripple upon the smooth surface of the sea.

Below, aboard the Glasgow, the passengers were at dinner.  They were laughing and joking among themselves.

Aboard the motorboats all was peacefully quiet.  The men not on duty were idling about and talking.

Suddenly Edwards, who stood forward on The Hawk, caught the peculiar fluttering of the signal flags aboard the Glasgow.

“Glasgow signalling, sir,” he reported to Lord Hastings.

Lord Hastings quickly drew the attention of Commander Thompson to the Glasgow’s signals, at the same time deciphering them for Frank and Jack.

The first signal read: 

“Small vessel dead ahead.”

Commander Thompson flashed back his response: 

“Submarine?”

“Can’t make out yet,” was the answer.

There was some further wig-wagging; and then the need for this means of communication suddenly ceased.

There came a sharp blast from the Glasgow’s horn and the big ship slowed down abruptly.  Then came the sound of a shot from dead ahead and there was a splash between the Glasgow and The Hawk.

“The enemy!” exclaimed Lord Hastings.

Aboard each of the small motorboats every man sprang to his post.  Soft commands carried back and forth across the water, while the signal flags of the Glasgow continued to flutter.