“This is a good time of night to call,” said the man with a peculiar emphasis. To Merritt it sounded as if the words just spoken were a sort of countersign. At any rate nothing more was said. The old negro admitted the stranger to the hut and closed the door.

“Now what sort of work is on foot,” muttered Merritt to himself. “What mischief are those rascals up to? It’s all most mysterious. This fellow whom we’ve seen with Jared first borrows electric batteries and then tries to send a cipher message. I can’t make it out.”

He stood a moment irresolute as to what course to pursue. Should he go back and tell Mr. Raynor what he had discovered? But the next minute he decided not to. After all he had no proof; he would try to peep into the hut and see what was going on. Cautiously he reconnoitered, completely circling the hut. But not a gleam of light was visible.

Bit by bit he crept closer, using the utmost caution. At length he got close to the rear wall and here, to his huge delight, he found a crack through which he could peer at what was going on within. What he saw made his heart leap. Round a table were seated Estrada, Alverado, the strange man and Jared Applegate. Jared’s face was white and frightened but the others wore a sort of deadly composure. In the background stood the old darky who had opened the door. On the table was a smoky kerosene lamp.

But on the table also were some objects that puzzled Merritt. There was a brass lever, not unlike a telegraph key, and by it an array of batteries with wires leading from them. The strange man was seated near the brass key, with which he was toying carelessly, and yet with a certain caution.

“Be careful,” Alverado was warning him, “don’t be premature, my dear Castro; in your eagerness you have already broken two batteries.”

“Yes, but the accommodating station agent replaced them. Ha! ha! if he had known what they were for! But he wouldn’t handle cipher, confound him!”

“That was the order of these hated Yankees. But after to-night we shall triumph over them. One touch of that key in the right direction and——”

Estrada, who was speaking, spread his hands expressively. The others’ eyes blazed; only Jared cowered and looked badly frightened.

“Why can’t you put it off till I get out of the country?” he begged.