"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…

"Four-way cock, a cock having two passages in the plug and four passage-ways for delivery, or one which unites four pipes so as to deliver from either one at will, according to the position of the valve. Such a cock is used in the continuous air-brake." -Whitney, 1911

Four-Way Cock Valve

"Four-way cock, a cock having two passages in the plug and four passage-ways for delivery, or one which…