"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…