ing into that ring it would be pretty sad to have
anything happen to it while we were gone."

"That's so," said the Banker, looking relieved. "I never thought of
that."

"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 foun