The moon was slowly shifting as he leant back and settled himself
comfortably in the high leather chair; the room was getting darker and
there had fallen that intense almost palpable stillness which envelops
most great cities after midnight, and against which his thoughts stood
out like steel points upon a velvet curtain.

Clear and sharp as steel they shot indeed, this way and that through
his mind; but hold them he could not, analyse or arrange them he could
not, neither would his hand move towards the pen a few inches from the
finger-tips.

"God!" he suddenly thundered, striking the arm of the chair with his
fist. "The answer is just there on the tip of my tongue--before my
very eyes--within reach of my fingers, and yet I cannot grasp it--ah!
why! could it _possibly_ be----"

He rose as he spoke and crossed to a massive bookcase packed to
overflowing with books, switched on a light hanging near, opened the
glass door and ran his hand lovingly over the leather volumes.

Then he very gently laid his hand on his left shoulder and turned with
a smile lighting up his face, which abruptly went blank in astonishment.

"Upon my word," he said, "whatever made me think that Jan had come in
and had put his hand upon my shoulder. Old fool that I am to-night."

For a moment he stood looking into the shadowy corners, then turned
again to the case, ran his finger along a row of books until he came to
one with the title "India," pulled it out and opened it under the light.