p back, and follow Piet Maartens and his friends
up," said Jack; and, stepping from the trench, he nodded to the young
officer and ran across to Guy.

A few minutes later the Boer spies appeared marching stealthily up the
hill, and as soon as they had passed by, Jack and Guy fell in behind
them. They kept steadily on, halting for a few seconds now and again to
listen and glance cautiously round them. Soon they were at the top of
the heights, when they turned to the left, and after proceeding some two
hundred yards came to a stop directly behind a battery of field-guns
placed in a most commanding position to rake the flats below. They
stood unguarded and unattended, save that below them, on the farther
side of the hill and some distance away on either hand, pickets were
posted.

"Looks as though they were going to play some game with the guns,"
whispered Guy. "What do you think, Jack? It would suit their purpose
well to destroy our cannon and then assault us."

"I think you are right, Guy. Let us hide up here and watch. At present
I do not think they will do much, for it is too light, but in another
hour perhaps they will make a move. By that time they will be
surrounded."

At this moment Piet Maartens rose to his knees from the hollow in which
he and his two companions had thrown themselves, and, not seeing anyone,
all three stole forward about fifty paces, and again lay prone upon the
ground, where they remained without a move, save that now and again one
of them raised his head and attempted to pierce the gloom. But the
night had already fallen, and it would have required more than the
unaided eye to distinguish any but a very close object.

Meanwhile Jack and Guy had crept into a good position near at hand, and
feeling sure that the officer in charge of the trenches had taken due
precautions to surround the Boer spies, they sat down in silence and
waited to see what would happen.

"Stay here a moment," said Jack, seeing that at present nothing was
likely to happen, "I'll go and get that officer, and then there will be
official evidence against those fellows. It looks as though we should
have them beautifully."

Leaving Guy crouching behind a mound of earth, Jack slipped back, and,
having reached the trenches, was soon in conversation with the officer.

"I wonder what their game is," said the latter. "At any rate we shall
nab them all, for I have put a circle of men all round the guns."

"I belie