"One of us should stay at least," said the Doctor. "We cannot take any outsider into our confidence. One of us must watch the others go, and then take the ring back to its place in the Museum. We will be gone too long a time for one person to watch it here." The Very Young Man suddenly went to one of the doors and locked it. "We don't want any one coming in," he explained as he crossed the room and locked the others. "And another thing," he went on, coming back to the table. "When I saw the ring at the Biological Society the other day, I happened to think, suppose Rogers was to come out on the underneath side? It was lying flat, you know, just as it is now." He pointed to where the ring lay on the handkerchief before them. "I meant to speak to you about it," he added. "I thought of that," said the Doctor. "When I had that case built to bring the ring here, you notice I raised it above the bottom a little, holding it suspended in that wire frame." "We'd better fix up something like that at the Museum, too," said the Very Young Man, and went back to his walk. The Big Business Man had been busily jotting down figures on the back of an envelope. "I can be in shape to go in three weeks," he said suddenly. "Bully for you," said the Very Young Man. "Then it's all settled." The Big Business Man went back to his notes. "I knew what your answer would be," said the Doctor. "My patients can go to the devil. This is too big a thing." The Very Young Man picked up one of the tin boxes. "Tell us how you made the powders," he suggested. The Doctor took the two boxes and opened them. Inside each were a number of tiny glass vials. Those in one box were of blue glass; those in the other were red. "These vials," said the Doctor, "contain tiny pellets of the completed drug. That for diminishing size I have put in the red vials; those of blue are the other drug. "I had rather a difficult time making them--that is, compared to what I anticipated. Most of the chemicals I bought without difficulty. But when I came to compound those two myself"--the Doctor smiled--"I used to think I was a fair chemist in my student days. But now--well, at least I got the results, but only because I have been working almost night and day for the past month. And I found myself with a remarkably complete experimental laboratory when I finished," he added. "That was yesterday; I spent nearly all last night destroying the apparatus, as soon as I found that the drugs had been properly made." "They do work?" said the Very Young Man anxiously. "They work," answered the Doctor. "I tried them both very carefully." "On yourself?" said the Big Business Man. "No, I didn't think that necessary. I used several insects." "Let's try them now," suggested the Very Young Man eagerly. "Not the big one," said the Banker. "Once was enough for that." "All right," the Doctor laughed. "We'll try the other if you like."