2006. Atkinson's melon pits (fig. 565.) are formed of brick, heated by dung, and consist of four external walls, of which the back and sides are four inches thick, and built in the pigeon-hole manner (a). The front is a hollow fourteen-inch wall, open at top withinside (b), and externally formed with thin bricks set on edge in cement (c). Against these walls the dung is applied as usual; by which means dry heated air is communicated to the pit from the front, and the damp warmth from the steam of the dung penetrates the pit at the back and sides. This contrivance is simple, and free from the objectionable points in M'Phail's pits, especially in being much less expensive and more roomy.