A quarter of an hour later he rejoined the Doctor, having brought with him a few short lengths of bamboo.
"I will put these across the hole when I get out," he said, "lay some sods over them, and cover them up with leaves, in case anyone should enter the bushes tomorrow.

It is not likely, but it is as well to take the precaution.

One of you had better stay on guard until I come back.
It would not do to trust any of the natives; those that remain are all utterly disheartened and broken down, and might take the opportunity of purchasing their lives by going out and informing the enemy of the opening into the gallery.

They must already know of its existence from the men who have deserted.

But, fortunately, I don't think any of them are aware of its exact direction; if they had been, we should have had them countermining before this." Having carefully closed up the opening, Bathurst went to the edge of the bushes and listened.