Still Trent held his command in waiting, for no orders had come to move it forward.

“The barracks are over there,” said Dave, pointing.  “So far as I have been able to judge, none of the bullets come from that direction.”

Still the desultory firing continued.  The occasional shots that rang out showed, however, that the Americans were not firing in force.

“There they go!” called Lieutenant Trent, drawing attention to the nearest barracks.  From the parade ground in front, small detachments of Mexicans could be seen running toward different parts of the town.

“Are you going to fire on them?” asked Darrin.

“Not unless the Mexicans fire on us, or I receive orders to fire,” the lieutenant answered.  “I don’t want to do anything to disarrange the admiral’s plans for the day, and at present I know no more than you do of what is expected of us.”

Suddenly the air became alive with the hiss of bullets.

“I see the rascals,” cried Dave pointing upward.  “They’re on the top of that building ahead.”

Trent saw the sharpshooters, too.  Perhaps twenty Mexican infantrymen occupied the roof of a building a few hundred yards ahead.  Some were lying flat, showing only their heads at the edge of the roof.  Others were kneeling, but all were firing industriously.

“Forward, a few steps at a time,” ordered the lieutenant.  “Don’t waste any shots, men, but pot any sharpshooter you can get on that roof, or any men who show themselves on other roofs as we advance.”

“This work is a lot better than getting into boats and trying to take Castle San Juan,” muttered Dalzell, as he drew his sword.  All three of the officers now had their blades in their hands, for the swords would be useful if they were obliged to fight at close quarters.

Crack! crack! crack! rang out the rifles of Trent’s detachment.  But every shot told.  Whenever any one of the three officers saw a man firing too rapidly that seaman was cautioned against wasting cartridges.

One of Trent’s men was already wounded in the left hand, though he still persisted in firing.

At the first street crossing Trent shouted: 

“Half of you men go down the street on that side, the rest of you over here.  Ensign Dalzell, take command over there.  Ensign Darrin, you will command here.”

The street was swiftly emptied of blue-jackets.  Hidden from the fire of the sharpshooters ahead, the sailors were out of immediate danger.  But both Dan and Dave stationed a couple of good shots at either corner, in the shelter of the buildings and took pot shots at the snipers ahead.

“Darrin, pick out two of your best men, and send them to lie down in the middle of the street, facing that roof-top,” Trent ordered, then shouted the order across the open street to Dalzell.

Thus, with four jackies lying flat in the middle of the street, and offering no very good targets to the roof snipers, and with two men behind each protecting corner, the Mexicans on the roof were subjected to the sharpshooting fire of the eight best shots in Trent’s command.