Examples from the Web for penstock
Penstock, pen′stok, n. a trough conveying water to a water-wheel.
Outside should be a penstock, to carry off the superfluous water.Hints on cheese-making|Thomas Day Curtis
Adjoining the engine-well are the grating tank and penstock chamber, and with these the principal main sewer communicates.A Comprehensive History of Norwich|A. D. Bayne
And that's where you will go back and back and back, as you said about building the penstock?Spacehounds of IPC|Edward Elmer Smith
At the gate is placed a vertical iron tube called a penstock, 7½ feet in diameter and 160 feet deep.Inventions in the Century|William Henry Doolittle