At the cry of spies all was confusion, and the revolutionists, with loud imprecations, sprang forward to seize the accused.

But quick as were the Mexicans, the Broncho Rider Boys were quicker! Evading the outstretched hands which would hold them, the boys dashed for the door, striking right and left at all who came within reach.

“Look out for the knives and use your fists,” cried Donald, as he planted a well directed blow on the point of Don Carlos’ chin, which laid that enthusiastic revolutionist low.

Billie and Adrian followed suit, and the two nearest them went down under their attack.

Another bound and they had reached the door.

“Shoot them,” cried Don Rafael. “They are friends of Gen. Sanchez!”

He drew his revolver and would have fired, had not the man nearest him knocked his revolver from his hand.

“You’ll hit our own men,” he said. “Who are you anyway?”

“I’ll show you who I am,” replied Don Rafael, beside himself with rage. “Take that!” and he aimed a blow at the man, which not only knocked the man down, but caused Don Rafael to nurse his fist with pain.

And now the boys are in the street and the whole band is after them, shouting and firing their revolvers indiscriminately.

Ordinarily such an affair would have created great excitement, but with firing in progress all about the city, it only attracted a few old men and boys, who joined in the pursuit.

“Get off the plaza,” cried Adrian. “Get into the dark!”

“Can’t we get our horses?” gasped Billie.

“No!” replied Donald as they ran. “Never mind the horses! Look for some place where we can hide.”

They darted down the first street which seemed to offer a refuge, with the whole band in hot pursuit.

“They’re gaining on us,” said Billie. “Let’s turn another corner!”

This they did and still another, but were unable to shake off their pursuers, who seemed to increase in numbers.

“In here!” at last cried Donald, as he noticed the door of a house standing partly open. “In here and shut the door!”

Suiting the action to the word, he darted in. The others followed, slamming the door behind them.

It was not a moment too soon, for the next instant the crowd came around the corner and passed down the street, thinking the boys still ahead.

It was pitch dark in the room into which they had stumbled, but Donald produced his electric light and they took a hasty survey of their surroundings.

“Here’s a candle,” he said. “We’d better light it and save our electricity.”

This they did, and as the dim light gave them a better view of the entire place they were all struck with its familiar appearance.

“It seems to me as though I had been in here before some time,” said Billie.

“Me too,” declared Adrian, and he looked about more carefully.

“I’ve got it!” exclaimed Billie. “It’s Villa’s house!”

“By George, you’re right,” said Adrian. “I wonder where he is?”

“It don’t look as though anyone had been here since we were,” said Billie.

“Maybe there hasn’t,” replied Donald. “This surely is a queer mess we have fallen into.”

The noise of a great commotion in the street and the sound of pounding on doors came to them through the grated window.

“The mob is returning!” said Adrian.

“What do you suppose the pounding is?” queried Billie.

“I should say they were breaking into the houses along the street,” said Donald.

“That is just what they are doing,” asserted Adrian. “Looking for us, no doubt.”

“We’d better barricade the door,” exclaimed Donald, and he grabbed the bed and pushed it against the door, while Billie pushed up the table.

“Not much to barricade with,” remarked Adrian and he piled up the chairs.

The work had hardly been completed when there was a knocking on the door.

The boys made no response.

“Open!” cried a voice, “in the name of the law, open the door!”

Still the boys made no reply; but they made ready to use their weapons if necessity demanded.

Then came blows upon the door, evidently from an ax, and in a moment the lock was shattered.

“It’s time to give them warning,” said Donald. “Fire through the first opening they make.”

The very next blow made the opening desired and three shots rang out. They were followed by screams from the street and the hammering ceased.

“They’ve found out that there is some one here, anyway,” said Billie. “I wonder what they’ll do next?”

A volley from without was his answer, but the shots were all high and no damage was done. The boys did not wait for a second volley, but jumped around to each side of the door, out of range.

Evidently believing that the shots had taken effect, the besiegers renewed their attack; but at the first blow the boys reached around and delivered their fire.

There was no answering shout to tell that the shots had taken effect, but the hammering ceased and a second later there was another volley.

“They are simply wasting their ammunition,” said Donald. “As long as we stay away from in front of the door they cannot possibly hit us.”

“They might batter the house down though,” said Adrian. “I wonder if there isn’t some way of escaping by the rear.”

“Suppose you go and look,” said Donald.

“I’ll go,” exclaimed Billie. “My experience in the smugglers’ cave has made me expert.” He dropped down on the floor and made his way on all fours to the back of the room.

There seemed to be but one entrance to the room and that was from the street. The entrance into the patio, which might have been expected, being lacking.

“I wonder why that is,” thought Billie. “All the Mexican houses I have ever seen opened into a patio.”

The patio is the little court around which Mexican houses are almost invariably built.

“Give me your electric light,” he at length said to Donald. “I am sure there must be an opening somewhere.”

Donald did as requested and Billie on all fours went carefully round the room, looking for a possible door.

“Here’s the place,” he finally exclaimed, “but the door has been walled up.” Then a moment later: “Hello, what’s this? A trap door.”

Quickly he brushed away the sand with which the floor had been covered, as is the Mexican custom, and the outlines of a door were plainly visible; but there seemed no way of raising it. Several times he passed his hand over the door, if perchance he could find a knob or a secret bolt, but in vain!

“I’ll have to pry it open with my hunting knife,” he finally exclaimed and began digging away with all his might.

“Are you sure it’s a door?” asked Donald, crawling over to where Billie was at work.

“Sure! Can’t you see?”

“It surely is,” said Donald. “Here, let me hold the light, while you get a good purchase with the knife.”

Billie handed over the electric light and gave the knife a vicious dig into the crack between the door and the surrounding floor. At the same time the besiegers struck the street door a terrific blow with the end of a steel rail which had been brought up from the railroad camp.

Just exactly what happened, Billie was at first unable to realize. All he knew was that the trap door, upon which he was leaning with one hand, had given way beneath him, and he was falling head first down a flight of stairs.

Picking himself up as soon as he struck bottom, which was not more than six feet, he started to ascend the stairs, but at the second step his head came into contact with the floor.

The trap door had flown back into its place.