wind-gap

He therefore pressed on again, but not so fast as before, and in half an hour's time he fancied that the wood was beginning to grow less dense, and that he was therefore coming to its boundary; but it proved to be only a large wind-gap in the forest, across which he made his way as quickly as possible, striking into a still denser part of the wood on the other side.

Under the Chilian Flag A Tale of War between Chili and Peru Harry Collingwood 1886