Observation with me is second nature. You appeared to be
surprised when I told you, on our first meeting, that you had
come from Afghanistan."

"You were told, no doubt."

"Nothing of the sort. I _knew_ you came from Afghanistan.
From long habit the train of thoughts ran so swiftly through
my mind, that I arrived at the conclusion without being
conscious of intermediate steps. There were such steps,
however. The train of reasoning ran, `Here is a gentleman of
a medical type, but with the air of a military man. Clearly
an army doctor, then. He has just come from the tropics,
for his face is dark, and that is not the natural tint of his
skin, for his wrists are fair. He has undergone hardship and
sickness, as his haggard face says clearly. His left arm has
been injured. He holds it in a stiff and unnatural manner.
Where in the tropics could an English army doctor have seen
much hardship and got his arm wounded? Clearly in Afghanistan.'
The whole train of thought did not occupy a second. I then
remarked that you came from Afghanistan, and you were astonished."

"It is simple enough as you explain it," I said, smiling.
"You remind me of Edgar Allen Poe's Dupin. I had no idea
that such individuals did exist outside of stories."

Sherlock Holmes rose and lit his pipe. "No doubt you think
that you are complimenting me in comparing me to Dupin,"
he observed. "Now, in my opinion, Dupin was a very inferior
fellow. That trick of his of breaking in on his friends'