Six, unmarked, firmly bound volumes in matching bindings consisting of: 'Harper's Boating Book for Boys, A Guide to Motor Boating, Sailing, Canoeing and Rowing': 'Harper's Outdoor Book for Boys'; 'Harper's Indoor Book for Boys'; 'Harper's Electricity Book for Boys'; 'Harper's Machinery Book for Boys'; 'Harper's Camping and Scouting, an Outdoor Guide for American Boys'. Each book has a b&w frontis with tissue protector plus numerous illustrations. Bound in red cloth with gold lettering and decoration on the front, black lettering on the spines. Each book over 300 pages. Spines are lightly sunned. Copyright dates range from 1907 to 1912.