spit

They [the potatoes] ſtood till October, when they were taken up, and a large pye made of them; which is laying them up in a heap, and covering them with ſtraw and a ſpit of earth.

Dig your clay with a ſpade in ſpits of ordinary bricks; dig two, three, eight, ten or twenty loads of clay, more or leſs as you pleaſe; … then take theſe ſpits of clay, after they are tried in the ſun, ſurround your pile of wood with them, …