CANALS.
RARE Boox Depr, Potts, Charles. =X The canal engineer's and contractor's assis- »322 tant, being an epitome of the theory of canal .18 cutting; with rules for gauging water, locating no.3 curves, calculating tables, &c. illustrated by
proper examples. Together with a new and exten- sive table of excavation, adapted to the dimen-
sions of the Pennsylvania Canal ... By Charles Potts.
Philadelphia: William Brown,printer. 1629.
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