the modern turbine, [202];a simple paddle-wheel, [202], [203];a wagon wheel, [203], [204];a barrel-wheel, [204], [205];an undershot-wheel, [206];a power-wheel, [206], [207], [208].Pens for reptiles, [47]-[51].Pet shelters, [29]-[51];for martins, [30]-[32];for birds, [32]-[34];