ly, a seventh of a mile in one minute. So if, on our chart, we take
one inch as representing one minute, we shall be working with a scale of
about seven inches to the mile."

"That doesn't sound very exact as to distance," I objected.

"It isn't. But that doesn't matter much. We have certain landmarks, such
as these railway arches that you have noted, by which the actual
distance can be settled after the route is plotted. You had better read
out the entries, and, opposite each, write a number for reference, so
that we need not confuse the chart by writing details on it. I shall
start near the middle of the board, as neither you nor I seem to have
the slightest notion what your general direction was."

I laid the open notebook before me and read out the first entry:

"'Eight fifty-eight. West by South. Start from home. Horse thirteen
hands.'"

"You turned round at once, I understand," said Thorndyke, "so we draw no
line in that direction. The next is--?"

"'Eight fifty-eight minutes, thirty seconds, East by North'; and the
next is 'Eight fifty-nine, North-east.'"

"Then you travelled east by north about a fifteenth of a mile and we
shall put down half an inch on the chart. Then you turned north-east.
How long did you go on?"

"Exactly a minute. The next entry is 'Nine. West north-west.'"

"Then you travelled about the seventh of a mile in a north-easterly
direction and we draw a line an inch long at an angle of forty-five
degrees to the right of the north and south line. From the end of that
we carry a line at an angle of fifty-six and a quarter degrees to the
left of the north and south line, and so on. The method is perfectly
simple, you see."

"Perfectly; I quite understand it now."

I went back to my chair and continued to read out the entries from the
notebook while Thorndyke laid off the lines of direction with the
protractor, taking out the distances with the dividers from a scale of
equal parts on the back of the instrument. As the work proceeded, I
noticed, from time to time, a smile of quiet amusement spread over my
colleague's keen, attentive face, and at each new reference to a railway
bridge he chuckled softly.

"What, again!" he laughed, as I recorded the passage of the fifth or
sixth bridge. "It's like a game of croquet. Go on. What is the next?"

I went on reading out the notes until I came to the final one:

"'Nine twenty-four. South-east. In covered way. Stop. Wooden gates
closed.'"