“Be sure to show us that. It’ll be interesting to find out first hand about smugglers.”

Though it was dark when they reached Brownsville, Jo Ann reminded the guard of his promise as he was about to get out of the car near the International Bridge.

“Sure, I’ll show you if you want to see,” he answered. “It’s black as pitch under the bridge now, and you’ll get a better idea of how the smuggling’s done.”

Jo Ann turned to Miss Prudence and rapidly explained that the guard was going to show them how some of the smuggling was carried on across the border.

Miss Prudence raised her eyebrows in disapproval. “I hardly think you girls need any information along such lines. Of course, it’s probably a little interesting—in a way—to see how smuggling could be carried on right under our custom officials’ noses, but——”

Jo Ann smiled to herself. Miss Prudence was as curious to know about smuggling methods as she was. “She’ll consent—after she objects a while.”

Jo Ann was right. Finally, after protesting a few more minutes, Miss Prudence gave her permission, and all five followed the guard below the bridge. Blinded by the sudden change from the lighted street, they stumbled along in the darkness, half terrified at their daring.

“The river’s very low now,” the guard explained. “Anyone can manage to crawl down the bank and get out a long way under the bridge and hide. Just before the smuggler, coming from the Mexican side, nears the appointed place, he whistles his signal to his confederate waiting under the bridge, then tosses his package over the railing to him.”

“There might be some of those smugglers here this very instant,” Miss Prudence whispered nervously. “Let’s go back.”

“They might think we’re spying on them and shoot us,” added Peggy.