But beyond that I could not go, and, perforce, was compelled to lie awake and think and think.

And that way, for an active-brained man, lay madness.
I sought devices to enable me mechanically to abide my waking hours.

I squared and cubed long series of numbers, and by concentration and will carried on most astonishing geometric progressions.

I even dallied with the squaring of the circle.

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