"Hydraulic Scroll. a, case, inclosing center-discharge turbine water-wheel; b, openings for inflow of water; c, c', gates for admitting water to central wheel-space d (the wheel is not shown); e, e', gate-shafts; f, shaft by which the two gates are operated simultaneously and equally from worm-gearing at the top of the gate-shafts." -Whitney, 1911

Hydraulic Scroll

"Hydraulic Scroll. a, case, inclosing center-discharge turbine water-wheel; b, openings for inflow of…