"On the day when the sketch disappeared, it happened in this way. When Tom, or rather, Peter, came into the room that evening with the tray containing your supper, he saw to his astonishment, lying carelessly on the table, the very sketch that he understood it was so important to guard. Immediately he saw the necessity of removing it to safety, as he knew that you were not in the secret about it, so he put his tray down on top of it, in apparent ignorance, and when you commanded him to remove the tray, he did so, cleverly concealing and holding the sketch underneath. When he went out of the room he still had it concealed under the tray, but once outside and the door closed, he dropped it to the ground while trying to transfer it to his pocket. It was this unfortunate accident that he feels sure led to its theft. In all probability, Madame Vanderpoel was watching from her nearly closed door and saw the sketch as it fell, and guessed it must be connected in some way with the secret we had been guarding. She immediately found some means to report it to her ally and companion-spy, Franz, and then the trouble began."
"But did Peter—I mean Mr. Brainerd—suspect Madame?" Patricia interrupted eagerly.
"He did not exactly suspect her, for she had done and said nothing of a suspicious nature. She certainly passed herself off very well for just what she wished to seem. She is an exceedingly clever woman. His only uneasiness about her arose from the rather peculiar actions of your little friend, Virginie de Vos. Still, as I say, Brainerd could not seem to connect her with any doubtful matters. Franz he did think was watching him, but even he did nothing to arouse direct suspicion. And, by the way, the 'Hofmeyer' that Chester heard referred to is none other than this precious 'Madame Vanderpoel.' It is, in fact, her real name, for she married, after her first husband died, a German named Hofmeyer. Little Virginie told me this to-night in a short interview I had with her. So there you have the famous two.
"Well, to continue. Peter intended to keep the sketch by him and return it to me at the earliest opportunity. But you know I got back very late that night, and so he thought best to retain it till morning, fearing it would arouse suspicion if he made an attempt to see me at so late an hour. He took the chance of my being a little upset at not finding it. He even thought it possible I might not discover its disappearance that night. Then, during the night, the sketch was stolen from his room; he does not even yet know how, but undoubtedly Franz was the culprit.
"Next morning at breakfast, if you remember, Peter jogged my shoulder with the tray, and I reprimanded him rather sharply. It was a preconcerted signal between us that he had something important to tell me. Later we met, and he told me what had happened and that Franz had disappeared from his accustomed post. We straightway went on a keen hunt after Franz, struck his trail at the railroad station, followed him to New York, pursued him from place to place all day, and finally had him arrested and searched, only to be disappointed in finding he had nothing of the sort on him. He must have got over to Hanford and left it there, or passed the sketch to Madame before she went, or something of the kind. At any rate, we had to let him go the next morning, as we had no evidence on which to hold him. After that, I came back here to find you and Chester had been the best detectives after all!
"The boy actually had the gumption to set the police on the trail of that Hanford crowd when he got back here. They went right out to raid the place. But alas! every one of the birds had flown. Not a trace of them anywhere. Very likely the maid gave the warning after Virginie got away, and they knew that the authorities would be hot-foot after them in a very short time. One consolation is that Madame will be known and spotted wherever she appears, so her usefulness as a German spy is over, in this country at any rate.
"I think that I have made a great mistake in keeping you in the dark about all these things, from the first. I might better have let you into the secret of the importance of the sketch and the fact that our waiter was only a secret-service man in disguise. But I wanted to spare you all worry about the matter, and I thought it would be perhaps safer for you if you knew nothing about my affairs. I see now that I should have done differently. But, at any rate, it has all turned out so well that we won't regret anything."
"But what a trump Chester has been! Did you ever see any one quite so clever?" cried Patricia, enthusiastically. "He is really the one who saved the whole situation."
"Yes, he is really a wonderful chap!" the captain agreed. "He beat Mr. Brainerd at his own job, and has done more for me than I can ever hope to repay. But he shall certainly have his reward, as far as I'm able to accomplish it. He wants to be a detective, but he is cut out for even better things if he only has the education and opportunities. I am going to arrange to have him put in a good school, and later he shall follow any line of work he seems best fitted for. He will certainly make his mark in the world some day."
"Well," murmured Patricia, with a little sigh of content, "Chester and Virginie have certainly lost nothing and gained much by the disappearance of the Crimson Patch, so I feel as if the adventure had been well worth while in every way, even though it did cause us an awful lot of worry!"