mazed that this man Whitburn allowed a thing like this to
assume the proportions it did. I must say that I seem to have gotten
the story about this business in a very garbled form indeed." He
laughed shortly. "I came here convinced that you were mentally
unbalanced. I hope you won't take that the wrong way, Professor," he
hastened to add. "In my profession, anything can be expected. A good
psychiatrist can never afford to forget how sharp and fine is the
knife-edge."

"The knife-edge!" The words startled him. He had been thinking, at
that moment, of the knife-edge, slicing moment after moment
relentlessly away from the future, into the past, at each slice coming
closer and closer to the moment when the missiles of the Eastern Axis
would fall. "I didn't know they still resorted to surgery, in mental
cases," he added, trying to cover his break.

"Oh, no; all that sort of thing is as irrevocably discarded as the
whips and shackles of Bedlam. I meant another kind of knife-edge; the
thin, almost invisible, line which separates sanity from non-sanity.
From madness, to use a deplorable lay expression." Hauserman lit
another cigarette. "Most minds are a lot closer to it than their
owners suspect, too. In fact, Professor, I was so convinced that yours
had passed over it that I brought with me a commitment form, made out
all but my signature, for you." He took it from his pocket and laid it
on the desk. "The modern equivalent of the _lettre-de-cachet_, I
suppose the author of a book on the French Revolution would call it. I
was all ready to certify you as mentally unsound, and commit you to
Northern State Mental Hospital."

Chalmers sat erect in his chair. He knew where that was; on the other
side of the mountains, in the one part of the state completely
untouched by the H-bombs of the Thirty Days' War. Why, the town
outside which the hospital stood had been a military headquarters
during the period immediately after the bombings, and the center from
which all the rescue work in the state had been directed.

"And you thought you could commit me to Northern State!" he demanded,
laughing scornfully, and this time he didn't try to make the laugh
sound natural and unaffected. "You--confine _me_, anywhere? Confine a
poor old history professor's body, yes, but that isn't me. I'm
universal; I exist in all space-time. When this old body I'm wearing
now was writing that book on the French Revolution, I was in Paris,
watching it happe