ess at once, together with his
age, birthplace, when vaccinated, and the residence of his maternal
grandmother. But you're not, so I'll let you off."

McCarthy turned the key idly about in his hand and tried it on a lock in
his desk. "Stopped up," he remarked, withdrawing it, and peeping into
the barrel; "not dirt, either--stopped up with paper! What's that for?"

He took a pin to clear the barrel, and the paper came away quite
readily. It was a tight little roll, which the surgeon pulled out into a
small strip rather less than three inches long and about half-an-inch
broad.

"Hullo!" he exclaimed. "Look here! Here's a job for Martin Hewitt, after
all! Figures! What does that mean? And what an amazing place to put
them in! A key barrel! By Jove, Brett, this looks like one of your
favourite adventures. Somebody sends a key in an envelope, and a row of
incomprehensible figures rolled up inside the key. Look at it!"

I took the key and the paper. The key was of a good sort; small,
inscribed "Tripp's Patent" on the bow, and it evidently belonged to a
superior lever lock. The paper which had come from the barrel was very
thin and tough--a kind I have seen used in typewriters. It had been very
carefully and closely rolled, and then pushed into the key so that its
natural tendency to open out held it tightly within. Written upon it
with a fine pen appeared a series of very minute figures, thus:--

9, 8, 14, 4, 20, 18, 5, 9; 15, 19, 20,
0, 3, 9, 8, 5; 3, 23, 0, 0, 5, 13, 14,
19; 19, 20, 0, 0, 0, 0, 6, 1; 5, 20, 0,
0, 0, 0, 3, 22; 1, 15, 0, 0, 0, 0, 18,
5; 1, 8, 20, 11, 18, 9, 5, 20; 12, 5,
23, 14, 14, 1, 1, 20.

"Well," inquired McCarthy, "what do you make of it?"

"Not much as yet," I admitted. "But it's pretty certain it must be a
cryptogram or code-writing of some sort; and if that's the case, I
_think_ I might back myself to read it--with a little time." For I well
remembered the case of the "Flitterbat Lancers," and the lesson in
cypher-reading which Hewitt then gave me.

"Come," my friend replied, much interested, "let's see how you do it.
Meantime we'll get on with our lunch."

I took a pencil and a spare sheet of paper, and I studied those figures
all through lunch and for some little time after. It soon became plain
that the problem was much more difficult than it looked, and I said so.
"At the first glance," I said, "i