Brick. Throughout the county the clays of the loess-loam make red brick. The principal manufacturers are the following: John Groff, three miles south of Winona; produces from six to seven hundred thousand per year; sells for eight dollars per thousand; oak wood costs from $4.50 to $5.00 per cord; uses the loam of the upper slope from the bluff. (The Geological and Natural History Survey of Minnesota, Volume I, 1872-1882, N. H. Winchell and Warren Upham, Johnson, Smith & Harrison, Minneapolis, Minnesota, 1884, Page 266)