. She overheard him once muttering something to himself about
"the unknown quantity," and that made her think that he had been working
too hard.

She decided he must see the doctor. The Professor refused peremptorily.
He declared he would be quite well again in the morning. The
housekeeper, an old servant, agreed, but sent for the doctor all the
same; and when he had come the Professor felt he could not refuse to see
him without appearing peculiar. And he did not wish to appear peculiar.
So he saw the doctor, but declared there was nothing much the matter, he
merely felt a little unwell and out of sorts and tired.

"You have hurt your hand?" the doctor asked, noticing how it was
bandaged.

"I cut it slightly--a trifle," the Professor answered.

"Yes," the doctor answered, "I see there is blood on it."

"What?" the Professor stammered.

"There is blood upon your hand," the doctor repeated.

The Professor looked. In fact, a deep, wide stain showed crimson upon
the bandages in which he had swathed his hand. Yet he knew that the
moment before the linen had been fair and white and clean.

"It is nothing," he said quickly, hiding his hand beneath the bed
clothes.

The doctor, a little puzzled, took his leave, but had not gone ten
yards when the housekeeper flew screaming after him. It seemed she had
heard a fall, and when she had gone into the Professor's bedroom she had
found him lying there dead upon the hearthrug. There was a razor in his
hand, and there was a ghastly gash across his throat.

The doctor went back at a run, but there was nothing he or any man could
do. One thing he noticed, with curiosity, was that the bandage had been
torn away from the dead man's hand and that oddly enough there seemed to
be on the hand no sign of any cut or wound. There was a large solitary
drop of blood on the palm, at the root of the thumb; but, of course,
that was no great wonder, for the wound the dead man had dealt himself
had bled freely.

Apparently death had not been quite instantaneous, for with a last
effort the Professor seemed to have traced an _X_ upon the floor in his
own blood with his forefinger. The doctor mentioned this at the
inquest--the coroner had decided at once that in this case an inquest
was certainly necessary--and he suggested that it showed the Professor
had worked too hard and was suffering from overwork which had disturbed
his mental balance.

The coroner took the same view, and in his short