A stone wall n in which two parallel lines of large stones are laid down and the middle filled in with smaller stones—also used as a mass noun.
1764 NY Mercury (NY) 16 July /3, [Advt:] It is . . fenced with a double Stone Wall to the Road; and for Fertility of Soil, and conveniency, exceeds any in Rochelle. 1798 Thomas’ MA Spy or Worcester Gaz. (MA) 7 Feb /4, [Advt:]A Valuable Farm, in Sterling, . . containing 100 acres of excellent Land, mostly fenced with double wall. 1851 OH Cultivator 7.52, Double Wall.—Prepare the ground as before. Make the bottom two feet in thickness, tapering to a foot or eighteen inches at the top. Put the largest stones on the outside and the small ones in the middle, keeping it level. A large stone laid occasionally across or through the wall, two feet from the ground, will bind the smaller stones and stregthen [sic] the whole. . . This may be faced on one or both sides. 1859 Genesee Farmer 20.213 ME, We build double, half-double, and single wall, without trenching. Good double wall is made four feet on bottom, two feet on top, and five feet high. 1931 Fitchburg Sentinel (MA) 9 June 6/2, An early settler in clearing his land built a fine double stone wall, and covered it with some of those great natural slabs so common to Lunenburg, and so much desired these days for garden stepping stones. 1932 Hanley Disks cMA, Double stone wall . . fill in the spaces between with small stones picked up in the fields . . Often built with a tilt, broader at bottom. 1933 Ibid seCT, Double wall’s got two faces. It’s faced . . on both sides, on the back side and the front side. 1989 DARE File cMA, Double wall.