into the ring, he gave into my
keeping, unknown to you, this envelope." The Doctor held it up.

"He made me swear I would keep its existence secret from every living
being, until the date marked upon it, at which time, in the event of his
not having returned, it was to be opened. Look at it." The Doctor laid
the envelope on the table.

"It is inscribed, as you see, 'To be opened by Dr. Frank Adams at
8 P. M. on September 4th, 1923.' For five years, gentlemen, I kept that
envelope, knowing nothing of its contents and waiting for the moment
when I might, with honor, open it. The struggle has been a hard one.
Many times I have almost been able to persuade myself, in justice to our
friend's safety--his very life, probably--that it would be best to
disregard his instructions. But I did not; I waited until the date set
and then, a little more than a month ago, alone in my office, I opened
the envelope."

The Doctor leaned forward in his chair and shuffled the papers he held
in his hand. His three friends sat tense, waiting.

"The envelope contained these papers. Among them is a letter in which I
am directed to explain everything to you as soon as I succeed in doing
certain other things. Those things I have now accomplished. So I have
sent for you. I'll read you the letter first."

No one spoke when the Doctor paused. The Banker drew a long breath. Then
he bit the end off a fresh cigar and lit it with a shaking hand. The
Doctor shifted his chair closer to the table under the light.

"The letter is dated September 14th, 1918. It begins: 'This will be read
at 8 P. M. on September 4th, 1923, by Dr. Frank Adams with no one else
present. If the envelope has been opened by him previous to that date I
request him to read no further. If it has fallen into other hands than
his I can only hope that the reader will immediately destroy it
unread.'" The Doctor paused an instant, then went on.

"Gentlemen, we are approaching the most important events of our lives.
An extraordinary duty--a tremendous responsibility, rests with us, of
all the millions of people on this earth. I ask that you listen most
carefully."

His admonition was quite unnecessary, for no one could have been more
intent than the three men silently facing him.

The Doctor continued reading: "'From Dr. Frank Adams, I exact the
following oath, before he reads further. You, Dr. Adams, will divulge to
no one, for a period of thirty days, the formulas set down in the