"Tough it is, but maybe not forever. My fighting blood is up, and I'm going to camp on the trail of that hound, Bixton, until I get something definite to hang on him," vowed Bob. "I want you two to keep an eye on him whenever you can. Watch where he goes, what he does, and the men he talks with. Be careful not to let him catch you at it, though. That'll be your part of the scheme." Bob rose and rolled up the newspaper he had been reading. "What are _you_ going to do. What's your part going to be?" Jimmy wanted to know. "Same as yours, only more so," grinned Bob. "I'm going to gather information about that kitchen detail, Bixton, Eldridge and anyone else who needs looking up. I'm going to be an investigator." Bob's earnest proposal that the three of them take to sleuthing on their own hook fired the enthusiasm of both Roger and Jimmy. Here was a real mystery to solve, more baffling than any they had ever followed in fiction. On their ability to ferret it out rested not only Schnitzel's life, but the saving of his good name from eternal dishonor. The next two days, however, were painfully devoid of results. Close and constant watch on Bixton developed nothing that could be used against him. Ignace had now returned to the fold a paler and slightly thinner edition of himself. According to himself he had been "'ver' seek, but no so seek som' other." He was greatly cast down over Schnitzel's plight, and sturdily expressed his belief in the other's innocence. He was equally eager to do whatever Bob advised, and solemnly promised, "Watch all time." On the afternoon of the third day after Schnitzel's arrest, Jimmy, Roger and Ignace received a summons to headquarters. At a loss to recollect any misdemeanor on their part, they went, wondering mightily why the K. O. should wish to see them. Once in the presence of their commanding officer they met with a shock. Before them, spread out on the major's desk, lay several letters, minus their envelopes, which reposed beside them. Each man was in turn requested to glance over the letter to which was affixed his signature, and state whether he had written it and at what time. It is needless to say that all told the same story. The letters on the major's desk were the letters that had so mysteriously vanished during the Khaki Boys' first week in camp. Having duly explained this to the K. O.'s satisfaction, they were treated to a second bewildering surprise. These very letters, it seemed, had been found in Schnitzel's suitcase. Major Stearns had opened them, as a point of duty, and had claimed the right to withhold them in order to make an inquiry. Shown to Schnitzel, he had stubbornly denied ever having seen them before. "You state, Blaise, that these letters were stolen from a shelf over your cot on the same night that they were written?" "Yes, sir." "Have you any reason for believing that it was Schnitzel who stole them?"