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?"