orway. But my curiosity satisfied, I returned at once to the
street and went to New York as I had planned."

"Do you mind telling us where you went in New York?"

"Not at all. I went shopping. I wanted a certain very fine wire, for
an experiment I had on hand, and I found it in a little shop in Fourth
Avenue. If I remember rightly, the name over the door was Grippus. Its
oddity struck me."

There was nothing left to the Inspector but to dismiss him. He had
answered all questions willingly, and with a countenance inexpressive of
guile. He even indulged in a parting shot on his own account, as full of
frank acceptance of the situation as it was fearless in its attack.
As he halted in the doorway before turning his back upon the room, he
smiled for the third time as he quietly said:

"I have ceased visiting my friend's apartment in upper New York. If you
ever want me again, you will find me amongst my books. If my invention
halts and other interests stale, you have furnished me this day with a
problem which cannot fail to give continual occupation to my energies.
If I succeed in solving it first, I shall be happy to share my knowledge
with you. Till then, trust the laws of nature. No man when once on the
outside of a door can button it on the inside, nor could any one without
the gift of complete invisibility, make a leap of over fifteen feet from
the sill of a fourth story window on to an adjacent fire escape, without
attracting the attention of some of the many children playing down
below."

He was half-way out the door, but his name quickly spoken by the
Inspector drew him back.

"Anything more?" he asked.

The Inspector smiled.

"You are a man of considerable analytic power, as I take it, Mr.
Brotherson. You must have decided long ago how this woman died."

"Is that a question, Inspector?"

"You may take it as such."

"Then I will allow myself to say that there is but one common-sense view
to take of the matter. Miss Challoner's death was due to suicide; so
was that of the washerwoman. But there I stop. As for the means--the
motive--such mysteries may be within your province but they are totally
outside mine! God help us all! The world is full of misery. Again I wish
you good-day."

The air seemed to have lost its vitality and the sun its sparkle when he
was gone.

"Now, what do you think, Gryce?"

The old man rose and came out of his corner.

"This: that I'm up against the hardest proposition of my