"I'll not keep you in suspense, my friends," began Mr. Sanders, without so much as clearing his throat, "but I'll just introduce myself to those who don't happen to know me. I'm Edwin Sanders of Eastern College, professor of science there." There was a murmur through the room at that announcement. "Professor!" was the surprised word it conveyed. "And I came here to experiment," the gentleman continued in a pleasantly matter of fact voice. "I found this little house had a direct air shaft, it runs from this room at that old fireplace down to the cellar, and out through an old-fashioned flue-door, you know the kind." "That's a relic on this place," spoke up Mr. Elmer Townsend. "It was built in here by a Dutch man from Holland--" "Yes, and it's a good one," agreed Mr. Sanders. "Well, you see, my friends," he continued, "I had to experiment on an extremely delicate little instrument," he was all professor now, "so, when I found the exact conditions that I required here, I made an offer to the owner, Mr. Townsend." There was much shifting around and significant scraping of chairs at this point, but the speaker was in no way disturbed. "I thought it only fair to tell him how important my experiment was, and what it would mean if it worked out as I expected. Well, it did," he stated emphatically, "but not without the usual trouble that must be endured if we want to succeed in big things." Miss Townsend was whispering, or she thought she was, and her brother was trying to restrain her. "I could not tell the nature of this work because there was a new secret principle involved in it," Mr. Sanders said, having overheard, likely, what Miss Townsend was trying to tell her neighbor. "That was why Mr. Townsend and I had to keep our secret so close." Ted and Buster were visibly squirming in their chairs, they were so interested, but old Nero snoozed contentedly, not even suspecting apparently, the presence of another dog, Tiny, that was safely hidden in Miss Townsend's cushion. And as if Mr. Sanders remembered Tiny, he next said: "Even the little dog was so interested as we worked he would insist upon barking a tune for us. Sometimes we were afraid he might tell," he finished, quizzically. "That was it," Ted privately told Buster. "Nancy said that puny, little dog barked all the time he was in here." "After I got my point worked out in this air shaft," went on Mr. Sanders, who had actually taken a sip of water from the glass at his hand, "I was obliged to try it out in a very much more condensed atmosphere. And just there is where I was forced to excite such wild suspicions." He was almost laughing at the recollection. "It was funny; I'm willing to admit that myself, for like the King of France in the story, I marched up the hill, but unlike him, I did not march down again. And I'm surprised that no one seems to have guessed where I was hidden." There was a pause. Nancy's face was betraying her suspicions but she uttered no word.