Jack was on the alert, ready to follow, but there was no need. Mr. Argent came back with a grim smile on his bronzed face.

"I thought I heard a movement there, as if some one were listening," he said, "but it was a false alarm."

"Are they trailing you as closely as that?"

"Yes, and more so," was the answer. "There's a big fight on to get this mine away from me and my friends, but we're going to beat our enemies. They'd give anything to get the information that is to come to me through the mail, and that's why I'm always on the lookout, fearing some one may overhear what I say."

"But I thought you knew where the mine is," said Jack.

"So I do, and I'm one of the very few men who do know the exact location."

"Then why are you expecting information through the mail that will disclose the place where it is?"

"You don't exactly understand," was the reply. "You see, after the man who first located the mine came back with some rich samples of gold from it, he died, and the place where he had made the strike was lost for some time. Then the documents giving the location were found by those entitled to share the wealth, and I came in on the deal.

"Now, in order to have everything perfectly legal it was necessary, in this particular case, to send to the authorities to have our titles made good. To do that we had to describe exactly where the mine was located. We had to send this information to the government officials in San Francisco. But of course our secret is safe with them.

"The trouble is, however, that they are now sending back to us our original documents, which give the location of the mine, and with them come our proofs to the claim, our legal title so to speak. Of course all these papers contain the written description of the location of the mine. If these papers fall into the hands of the men who are working against us they may jump our claim, as they call it, for it is not yet legally secured to us.

"That is why I am so anxious not to have the expected letters lost. So if you get them, Jack, take good care of them."

"You can make sure I will!" exclaimed the pony rider.

"Oh, I'm not worrying about you, Jack. I mean I know I can trust you, just as I could have trusted your father were he on the express route. It's the other fellows I'm worrying about. They held you up once, Jack, and—"

"They won't get a second chance!" exclaimed the lad, with flashing eyes.
"I'll be on the watch."

"Well, they're pretty foxy and cunning," went on the miner. "It's treachery more than anything else you have to fear now; treachery and guile. They'll try them now they've found out their hold-up methods didn't work!"

"Well, they may try them again," said Jack, "but they won't catch me napping again."

"Oh, I guess you weren't napping, Jack."

"No, not exactly. It all happened so suddenly they didn't give me a chance.
Though I suppose that was their game. Well, I'll do my best."

"I know you will, Jack. Now, as I said, I don't know just when the documents will come. If I did I'd be there myself, and bring 'em through. I wouldn't ask you to take the risk."

"Oh, the risk is part of the game," Jack said.

"I know it is, but I don't believe in anybody—man or boy—taking too many. But, not knowing when they'll arrive, I'll have to trust the regular mail service. Only one thing, Jack. Don't bring them through at night. I mean by that, don't make a night trip just for my papers. Of course, if you have to make a night ride anyhow, and the documents arrive at Golden Crossing, bring them along with you. But don't make a special trip on their account, as there is no rush about them. I suppose you can depend on the people at the other end of the line—I mean in the Golden Crossing office?"

"Well, I should say I could!" declared Jack, energetically. "Jennie Blake is postmistress there and—"

"Oh, I forgot. She's a relative of yours, isn't she?"

"Yes," answered Jack, and he blushed under his coat of tan.

"Well then of course it's all right. I am not greatly worried about the transportation from San Francisco to Golden Crossing. It's from there to here the documents will be taken, if at all."

"They won't be taken at all!" declared Jack. Of course, he was boyishly enthusiastic. For that one can not blame him. He was deeply interested in his work. To him it meant everything. He wanted to bring the mail through safe, and on time every trip. And, so far, he had more than made good.

That one hold-up did not count against him, especially as he had so soon recovered the bulk of the stuff.

"Well, I guess that's all I have to say to you, Jack," concluded the miner. "As I remarked, I can't say just when the papers will arrive. And when they do—well, take the best care of them you can."

"I wonder how it would do to try another ruse, and hide them, say in a loosely tied package, that looked as if it didn't contain anything more valuable than a pair of old shoes?"

"That might answer. But as you tried that game once, and it didn't work, it would hardly deceive the outlaws a second time. But use your own judgment, Jack. I leave it all to you. Only bring me the papers, and don't let the other fellows get them."

"I won't!"

"Shake!" exclaimed the miner, and their hands met in a firm clasp.

Jack rode the trail that day, reaching Golden Crossing with the packages and letters.

"Well, Jennie," he remarked, "the game is on."

"What game?" she asked. "I hope you don't mean any more bogus inspectors are coming here."

"No. I mean that any time now that package of mine documents may reach here. When it does, put it in the safe if I'm not here."

"And what are you going to do with it?"

"Carry it to Rainbow Ridge, of course."

"Oh, Jack! Suppose something happens?" half whispered Jennie.

"Well, I hope it doesn't. And I'm going to do my best to see that something doesn't happen. But if it does, well, I'll have to put up with it, I suppose," Jack said, with a shrug of his shoulders.

"I almost hope the old package doesn't come," murmured Jennie, with a pout of her pretty lips.

"Oh, that wouldn't do," said Jack. "It's very valuable and important. And that's what the pony express is for—to transport speedily valuable and important packages and letters. I'll make out all right, I guess."

"I—I hope so," she faltered.

For several days after that Jack watched the mails anxiously for a sight of the package of documents relating to the mine. But it did not come, and as he made each trip he planned what to do at certain points of the road, where he might possibly be held up again.

"Though it's a question, just as Mr. Argent says, whether they would try the same tactics twice," Jack reasoned. "They may try some other game. I'll have to be on the watch for both."

Mr. Argent himself was getting anxious now. Each time Jack came into Rainbow Ridge from his trip, the miner asked if the letters had come. Each time Jack answered in the negative.

"Well, they'll be along any day now," Mr. Argent would say. "Be on the lookout."

Jack was idling about the Golden Crossing post office about a week after he had received the caution to be on his guard. He was waiting for the stage to come in with the western mail, with which he expected to make the ride back to Rainbow Ridge.

A dusty messenger rode up on a tired and lather-covered horse, and called to Postmistress Jennie:

"Is the pony express rider here?"

"Yes," answered Jack, coming forward. "What's wanted?"

"Stage has had a bust-up a little way out," the messenger said. "I come in to get help, and to say that the driver wants to see you."

"Wants to see me?"

"Yes, he's got a bundle of mail that's marked 'Rush,' and he wants to know if you can ride out there, get it and take it on to Rainbow Ridge."

"Well, I suppose I can," Jack said, "though it isn't regular."

"No, he told me to tell you he knowed that. And he said he'd have sent the mail in by me, only there's some valuable stuff in it, and he wants a regular man to take it. So will you go out?"

"I think I'd better, yes. How far out is the stage?"

"About five miles. Half way between Bosford and Tuckerton," was the answer.

"All right, I'll ride out and get the mail," decided Jack, and in due time he arrived at the place where the stage had been delayed because of a broken wheel. The mail was transferred to Jack, and he started back with it.

"I wonder if the important letters can be in this bag," mused Jack, as he urged Sunger onward. There was no way of telling.

The stage, as the messenger had said, had broken down half way between Bosford and Tuckerton. These were two small settlements, the last one being about three miles from Golden Crossing.

As Jack was passing through the eastern outskirts of Tuckerton he noticed that Sunger was limping slightly.

"Hello! What's this? Got a stone under your shoe?" he exclaimed, as he got off. He made an examination and found that such was the case. Sunger had gone lame, though not so badly but that, with the removal of the stone, the animal could be ridden.

"I'll fix you up," Jack said, as he guided the pony to a shady spot on the trail, and proceeded to get out a simple kit he carried with him for emergencies.