Note 227 — Chapter IX · [IV]
Reading edition
The ordinary meaning of the word "dalles" is paving stones; but by the Canadian French it was also used to indicate a channel which carried off the waters dammed above—hence any form of confined, swiftly-flowing waters. Lewis and Clark spoke of these chasms through which the Columbia rushes as the Long and Short Narrows; by Farnham's time the term "Dalles" had become the ordinary appellation.—Ed.