in mining, a term used in Cornwall, to express any of the openings of the earth either into mines or in search of them. The fruitless openings are called empty-hatches; the real mouths of the veins, tin-hatches; and the places where they wind up the buckets of ore, wind-hatcher.

HATCHES also denote flood-gates set in a river, &c. to stop the current of the water, particularly certain dams or mounds made of rubbish, clay, or earth, to prevent the water that issues from the stream-works and tin-washes in Cornwall from running into the fresh rivers.