which was pinned a sheet of cartridge paper.

"Now," said he, seating himself at the table with the board before him,
"as to the method. You started from a known position and you arrived at
a place the position of which is at present unknown. We shall fix the
position of that spot by applying two factors, the distance that you
travelled and the direction in which you were moving. The direction is
given by the compass; and, as the horse seems to have kept up a
remarkably even pace, we can take time as representing distance. You
seem to have been travelling at about eight miles an hour, that is,
roughly, 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