Bark

Outer layers of the stem of exogenous plants. IMG:content-0429.png:[graphic][subsumed][subsumed][subsumed][merged small][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][merged small][merged small][graphic][merged small][merged small] IMG:content-0430.jpg:[blocks in formation] Barker's Mill. Hollow shaft having hollow radiating arms, and turned by the reaction of water escaping through them; often called the reaction water-wheel. Its efficiency as a motor is low unle the speed be very high, and hence it is rarely used as a waterwheel. See HYDRAULIC TOURNIQUET. IMG:content-0431.png:[graphic] IMG:content-0432.png:[graphic] Barker's Mill.