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Webster 1913 Edition
Penstock
Pen′stock
,Noun.
[Etymol. uncertain; perh. fr.
pen
an inclosure + stock
.] 1.
A close conduit or pipe for conducting water, as, to a water wheel, or for emptying a pond, or for domestic uses.
2.
The barrel of a wooden pump.
Webster 1828 Edition
Penstock
PEN'STOCK
,Noun.