tered the path with a resolute and
martial air. Miss Lambart was not impressed by it. She thought that
in his tight-fitting clothes of military cut and his apparently
tighter-fitting patent leather boots he looked uncommonly out of place
under the green wood trees. She remembered how lightly the Twins and
the princess went; and she had the poorest expectation of his getting
near any of them. Also, as they had come up the aisle of the woods she
had been assailed by a late but serious doubt, whether a
weight-carrying motor-car was quite the right kind of vehicle in which
to approach the lair of the Twins with hostile intent. Its powerful,
loud-throbbing engine had seemed to her to advertise their advent with
all the competence of a trumpet.

Her doubt was well-grounded. The quick ears of Erebus were the first
to catch its throbbing note, and that while it was still two hundred
yards from the entrance of the path to the knoll. Ever since the
departure of Miss Lambart and Sir Maurice the Twins had been making
ready against invasion, conveying their provisions and belongings to
the secret caves.

The secret caves had not been secret before the coming of the Twins to
the knoll. They were high up on the outer face of it, airy and well
lighted by two inaccessible holes under an overhanging ledge. But the
entrance to them was by a narrow shaft which rose sharply from a cave
in the heart of the knoll. On this shaft the Twins had spent their
best pains for two and a half wet days the year before; and they had
reduced some seven or eight feet of it to a passage fifteen inches high
and eighteen inches broad. The opening into this passage could,
naturally, be closed very easily; and then, in the dim light, it was
hard indeed to distinguish it from the wall of the cave. It had been a
somewhat difficult task to get their blankets and provisions through so
narrow a passage; but it had been finished soon after breakfast.

They were on the alert for invaders; and as soon as they were quite
sure that the keen ears of Erebus had made no mistake and that a car
was coming up the board aisle, the princess and the Terror squirmed
their way up to the secret caves; and Erebus closed the passage behind
them, and with small chunks filled in the interstices between the
larger pieces of stone so that it looked more than ever a part of the
wall of the cave. Then she betook herself to a point of vantage among
the bushes on the face of t