XXVIII Canals. HOLLAND.
out Holland for works of this description is estimated at six
million florins. A corps of engineers, termed De Waterstaat, is
occupied exclusively in superintending these works. The con¬
stantly immine7it nature of the danger will be thoroughly ap¬
preciated by the stranger, if he stands at the foot of one of the great
dykes at high tide, and hears the breakers dashing against the other
side of the barrier, at a height of 16—18 ft. above his head.
Canals intersect the country in every direction. They serve a
threefold purpose: (1) as high-roads, for purposes of traffic ; (2) as
drains, by which superfluous water is removed from the cultivated
land; (3) as enclosures for houses, fields, and gardens, being as
commo7ily used for this p7irpose in Holland as walls and hedges in
other countries. The Dutch canals differ from those in most other
countries in being generally broader, b77t variable in width, while
locks are rare, as the level of the water is nearly always the same.
Those, however, which are connected with the sea are closed at
their extremities by massive flood-gates , to prevent the encroach¬
ment of the sea whe7t its level is higher than the water in
The principal canals are abot7t 60 ft. in width, and 6 ft. in
depth. Not only the surface of the water, hut the bed of the ca7ial
is ofte7i considerably above the level of the surrounding country.
The great North Canal (p. 224), an admirable monument of Dutch
skill and perseverance, is about 50 M. in length, 39 yds. in width,
and 20 ft. in depth. A still more laborious undertaki7ig was the
construction of the Netv Canal across 'Holland op zijn smaalst'
(p. 231), connecting Amsterdam and the North Sea. This magni¬
ficent channel of communication is 15'/2 M. in length, 65—110 yds.
in breadth, a7id 23 ft. in depth. The cost is estimated at 26 million
florins. The Willems- Canal in N. Braba7it (p. 236) is also worthy
Polder is a term applied to a morass or lake, the bed of which
has been reclaimed by draining. A great part of Holland and
Flanders has been thus reclaimed, and re7idered not only habit¬
able, but extremely valuable for agricultural purposes.
The first step in the process of drainage consists in enclosing
the marsh with a dyke, to prevent the admission of water from
without. The water is then removed by means of water-wheels of
peculiar construction, driven by windmills or steam-engines. The
marsh or lake to be reclaimed is sometimes too deep to admit of the
water at once being transferred to the main canals, and thus carried
off. In these cases a syste7n of dykes, one within the other, and each
provided with a canal on its exterior, forms an ascending series of
levels, from the lower of which the water is gradually transferred
to the higher, and thence finally into the principal channels. An
excellent example of this is seen in the Schermer-Meer, where four
different levels have been formed. These canals, although separate