New-York tribune., 1902-12-14

should be added the height of the foundation,
structure Of granite masonry. laid up with hy
draulic cement mortar. and dipping to a con-
siderable distance in spots. One great diff
Guilty encountered was the rotten character OF
the rock here and there the bottom. 1t there
fore became necessary to excavate extensively
to find q sound bed for the foundation The
front and rear faces OF the dam are composed
Of granite masonry, with a filling Of rubble, set
In cement and placed by hand
To provide for the escape Of the surplus water
at times OF food the dam is pierced with $50
sluices, most of them % feet high and 6i2 feet
wide When the river is rising in summer these
sluices will be kept open, and the red silt
which discolors the fluid, and which possesses
great fertiliZing value. Is expected TO pass
through freely. When the discharge has dlInln-
ished to a certain point and the water has again
become clear the gates viii be closed In addl-
ton to these passages, there are four locks
each measuring go by ;}2 feet. for the benefit
of navigation. These are arranged so close to
each other as % constitute a ladder, and are
situated in a canal at one end Of the dam Five
gates serve for the four locks Each gate has
q depth Of 90 feet, and instead Of swinging on
q hinge il moves on rollers above It, as DO GER
tain sliding doors in houses
The special object Of this is to secure sup
ply Of water for irrigation purposes in the dry
season. and thus reclaim vast amount OF lana
that is now useless. It is estimated that the
Increased value of property in consequence OF
the benefit conferred on agriculturists viii yield
a return in taxes that viii far more than pay
the cost Of the undertaking.
while the Assouan dam, storing one thousand
million tons Of water is by far the most elab-
orate structure of its kind along the Nile, II Is
not the first that has been erected for the same
purpose Below Cairo, and at the head OF the
delta the Nile divides into two principal out
lets-the Rosetta and Damietta branches. what
are known as barrages were built across theSe'
not far from the point Of separation, haIf a
century ago They are harmless at times OF
food. but store water in the dry season. These
barrages which are something like l2O or 13o
miles from the Mediterranean, are brick via
ducts COMPOSED of a series Of arches, each haV-
ing span Of over sixteen feet Inc arches
contain sluices, which can be opened or closed
as occasion demands. Some Improvements have
recently been undertaken with a view TO
STRENGTHENING this work A new baTrage mas
,ecantIv been constructed at Assiout, 80 miles
above Cairo and nearly four hundred miles
from the sea This is built Of stone, not brick
but resembles the one at the delta in general
5e.;gn If WAS begun in 1898 and finished
,avu r,onths ago. The contractors, Sir John
Airs 4, Co also built the big dam at Assouan
81, hundred miles further up. The Assloul
barrage will increase the utility of the one below
Cairo. The waters held back by the latter can
now be diverted into canals in Middle Egypt
and the Fayoum, and will bring under irriga-
zion three hundred thousand more acres OF
Land. ,,.
lust above Assouan is the island OF Fhii',
on which there ruined temples oOeiISAs SiN
other objects of interest to the antiquary. II
has been feared that the new dam would tend
q. ,,,5ary,ine these 1.-The Scientific American,
from which many of the foregoing details are
ATTAINED SAYS that underpinning has been
,,ovided for the more important parts OF the
island. so that no anxiety need be felt on that
score.