tremendous application of steam and gunpowder. An engine bored holes
in the rock fifteen feet deep and twelve inches in diameter; and these
were so placed, and in such numbers, that at a single blast 170 tons
of granite were blown into the air--an operation hardly conceivable.
This canal leaves the town in a westerly direction--being, at its
outset, about a quarter of a mile from the Merrimac, but gradually
approximating for a quarter of a mile, until it touches and unites
with that river. Between the two, is one of the prettiest of public
walks, ten feet wide, having rows of trees on each side, and
terminating in a point; being the end of a splendid granite wall, at
its base thirty feet thick, and tapering to half the thickness,
dividing the natural from the artificial stream. Here we come to a
point of great interest: on the right is an artificial dam across the
river, with two sharp lines at an angle of sixty-seven degrees, the
point meeting the stream, thus stopping the waters, and insuring a
supply for the reservoir, while it forms a cascade of about twenty
feet.

My friend gave me a very graphic description of the opening of the
works. The whole was built in a cofferdam, quite dry, and the opening
was a holiday. Every spot within sight was covered with spectators,
for whom the engineer had contrived a surprise. The works used in
keeping the water out of the reservoir, and protecting the new dam,
were undermined, and charged with gunpowder. At a given signal, the
train was fired, and in an instant the whole blew up; and when the
smoke cleared away, the fragments were floating down the Merrimac, and
the canal full of water.

On the left from the point, the egress of water is regulated by
flood-gates of a superior construction. The building crosses the