s," said he, "that you are the
most companionable fellow in the world. You have the heaven-sent gift of
silence."

"If silence is the test of companionability," I answered, with a grin,
"I think I can pay you a similar compliment in even more emphatic
terms."

He laughed cheerfully and rejoined--

"You are pleased to be sarcastic, I observe; but I maintain my position.
The capacity to preserve an opportune silence is the rarest and most
precious of social accomplishments. Now, most men would have plied me
with questions and babbled comments on my proceedings at Scotland Yard,
whereas you have allowed me to sort out, without interruption, a mass of
evidence while it is still fresh and impressive, to docket each item and
stow it away in the pigeonholes of my brain. By the way, I have made a
ridiculous oversight."

"What is that?" I asked.

"The 'Thumbograph.' I never ascertained whether the police have it or
whether it is still in the possession of Mrs. Hornby."

"Does it matter?" I inquired.

"Not much; only I must see it. And perhaps it will furnish an excellent
pretext for you to call on Miss Gibson. As I am busy at the hospital
this afternoon and Polton has his hands full, it would be a good plan
for you to drop in at Endsley Gardens--that is the address, I think--and
if you can see Miss Gibson, try to get a confidential chat with her, and
extend your knowledge of the manners and customs of the three Messieurs
Hornby. Put on your best bedside manner and keep your weather eye
lifting. Find out everything you can as to the characters and habits of
those three gentlemen, regardless of all scruples of delicacy.
Everything is of importance to us, even to the names of their tailors."

"And with regard to the 'Thumbograph'?"

"Find out who has it, and, if it is still in Mrs. Hornby's possession,
get her to lend it to us or--what might, perhaps, be better--get her
permission to take a photograph of it."

"It shall be done according to your word," said I. "I will furbish up my
exterior, and this very afternoon make my first appearance in the
character of Paul Pry."

About an hour later I found myself upon the doorstep of Mr. Hornby's
house in Endsley Gardens listening to the jangling of the bell that I
had just set in motion.

"Miss Gibson, sir?" repeated the parlourmaid in response to my question.
"She _was_ going out, but I am not sure whether she has gone yet. If you
will step in, I will go and see."

I fo