The lieutenant said nothing, but stroked his whiskers which he wore in exact imitation of his chief.

"Lucky for the general," he whispered, and Donald nodded his head that he understood.

The two Mexicans exchanged a few words under their breath which Donald could not hear and then the officer took from his breast pocket a large wallet, from which he counted out ten bank notes.

They were yellow backs and Donald was not at all surprised when the officer said:

"Here are ten one-thousand-dollar bills in American money. We believe you are telling us the truth, as your words are corroborated by the men who brought him here. But if you are playing us false, we shall know how to reach you."

The American shrugged his shoulders as he took the bills, rolled them up nonchalantly and placed them in his trousers pocket.

"You can find me at the Hidalgo Hotel whenever you want me," he said, "and now I must be going."

He arose from his seat, and as he did so, Donald caught sight of his face. It was the mountebank, Strong, but in his stylish clothing Don had failed to recognize him.

"Great Scott!" he muttered to himself, "the plot thickens!"

"What's that?" queried the lieutenant, who caught the muttered exclamation.

"Nothing much," replied Donald as the three men walked toward a door in the farther end of the room and he was enabled to speak without being heard, "only that is the man I'm looking for. Let's get out of the window and see if we can't head him off."

He closed the door and turned the key which he had quietly taken from the other side.

The windows were open and they looked out. They were on the side of the house overlooking a good-sized lawn.

"That's the reason they are not barred," explained Donald. "Had they been front windows, we might as well have been in jail. You go first and I'll cover the retreat."

Lieut. Grimes sprang into the window and lowered himself to the ground, just as a hand turned the k.n.o.b.

"Good-bye!" muttered Donald. "Sorry I can't wait to receive you,"

and he followed the lieutenant.

On the ground they could hear the men trying to open the door and as they sped across the lawn toward a high brick wall, the door gave way with a crash and they could hear surprised voices.

"They have discovered our wreckage!" cried Donald. "Over the wall you go!"

"You first this time," said the lieutenant.

"No, you first. I can boost you up, but I couldn't pull you. You can pull me."

The argument was good and the lieutenant acted upon it.

A minute later he was on top of the wall.

"Great Caesar!" he exclaimed. "There's nothing under me but water."

"Never mind that," was the response. "Haul me up."

The lieutenant leaned down and gave the lad a hand.

"Here we are," he said a minute later. "We can't jump in, for there is no knowing where we are."

"Sure," from Donald. "Let's run along the wall."

This they did for about a hundred yards and then the wall ended abruptly against what appeared to be an abutment.

"We must act quickly," declared Donald. "They think you are Funston and won't hurt you. Keep up the deception. I'm going to swim for it. I'll have help here just as quick as I can. So long," and, throwing off his coat, he jumped into the water some twenty feet below.

CHAPTER XXVII.

THE ADMIRAL TO THE RESCUE.

When Donald struck the water he allowed himself to go clear to the bottom, as he wanted to find out just about how deep it was.

It was, as he had expected, about the depth of the water in the harbor and he made up his mind that he could not be far from some of the wharves that const.i.tute the water front.

When he came to the surface, he struck out away from the wall, and by the light of the moon was soon able to see the vessels in the offing. He could also see that he was well north of the princ.i.p.al docks.

"I guess I'll land at the first place that offers," he thought, "and find my way to headquarters from there."

He struck out l.u.s.tily, but had not been swimming more than a couple of minutes, when he heard the sharp exhaust of a gasoline launch.

Realizing that it must be an American craft, he shouted at the top of his voice.

At first there was no response, but as the boat came nearer and he shouted even more loudly, a friendly hail came over the waters.

"Where are you?" came the voice as the boat came to a stop.

"Here, to your port side," he replied.

The launch was started again slowly and Donald was soon able to make himself visible.

"Who are you?" was the first question pumped at him by the officer in command.

"Special messenger for Gen. Funston," was the response.

"Where is your uniform?"

"I'm not a soldier. I am a civilian."

"A likely story," snapped the officer, who chanced to be an ensign.

"I can't help how likely it is," snapped Donald in return. "It's true, and I want to be put ash.o.r.e as quickly as possible. I have an important message and the safety of one of his staff is involved. There is also a plot on foot to capture the general himself."

"Nonsense! And besides, I can't put you ash.o.r.e. I am carrying a message to Admiral Fletcher."