Jack stepped over to the supply wagon and soon returned bearing one of the tins in question, which Toby noticed now was a trifle more bulky than others that he remembered seeing containing prepared soups. "This is quite a clever idea," proceeded Jack. "You see, it consists of really two cans, one inside the other. The narrow space between is filled with unslacked lime. When you feel like having a meal, all you have to do is to punch a hole close to the edge on top, and pour in some cold water. This immediately makes the lime furiously hot, and in a short time you can open the main can and your soup is almost scalding. I tried one can at home, and it worked to a charm. My dad was quite tickled with it, and said they never had such splendid things when he was young and used to go off into the woods on camping or surveying trips." "Oh! I see we're not going to starve yet awhile, even if we can't have a nice pot of coffee while on the job," laughed the pleased Toby, handling the wonderfully self-heating can of vegetable soup almost reverently. So the afternoon passed. Jack had everything laid out, for, as he said, it might be well for them to get an early start on the following morning, since they had quite a tramp before them, and would want to take their time during the latter half of the journey, when there might be more or less danger of discovery. "Of course," Jack assured them, "I don't expect to keep this sort of thing up all the time we're here in camp. That would be making it too much a matter of business. Once I've settled on what this Mr. Maurice is doing, and managed to gather up all the evidence necessary, I shall put him out of my mind; and after that we'll just enjoy ourselves to the limit, as we deserve." "Hurrah!" cried Toby; "and if ever any fellows had a better chance to enjoy themselves I'd like to know it; with such a splendid tent for a shelter, a jolly camp stove that keeps you warm in chilly or wet weather; and ten days left that can all be filled with delight." "Don't forget that we've another cause for rejoicing in the possession of a most delightful stock of things to eat," interrupted Steve, sagely, "as well as a real biscuit and flapjack _chef_ who's willing to lay himself out to the limit for the good of his chums." The rest of the day proved all that could be desired. It warmed up considerably, too, although when the sun had set in a blaze of glory, and evening began to steal softly upon the scene, there was a little tang to the air that made the campfire, built outdoors, feel doubly acceptable to them.