Weekly national intelligencer., 1851-02-01


face Of this portal is built Of hard white sandstone IL
ambs "a feet apart and carried up 10 feet above
canal bottom circular arch springs from these ambs
the Of which is Of "a feet above canal bottom
The of which this portal is built is made to extend
back 25 feet where il with the brick ning of the
tunnel which has for its whole length the with
the portals the upper portal and the lower being in
every respect alike.
The examination Of this tunnel carried on for its entire
length Of liz feet through the solid slate rock bench
which feet broad and feet high being left for towpath
The side Of this bench protected by ls inch wall
hard burnt bricks, laid in hydraulic cement filled in with
concrete back the rock The brick wang on both sides
and also the arch of the description of BRICK of The
same thickness, and laid in manners filed in with con
crete from canal bottom height of quarter Of the ARCH
the the remainder Of the arch being closely packed
with spaHs
The towpah wall is covered by coping Of locust TIMBER
secured by crosses every FIVE feet and on this coping there
is an iron railing tenders of timber bolted the walls
both sdes to prevent injury from the conclusion of boats
the bolts extending through the walls two feet into the solid
rock
The level from lock No. &C. continued through the tunnel
and onward to lock 81, is miles in length. Abou,
hall mile after passing the last mentioned rock
the aqueduct Town Creek" This structure Of the
same description of limestone Of which the Anetam and
several other Of the aqueducs built it single arch
Of 6O feet span l5 feet se with the portions of and rub
bic work same all the others above Licking Creek
The level OF the canal in this aqueduc, being that from
lock 81 10 90, is fraction three miles, Lock 60 OPP
Posite the junction of the South Branch of the Potomac.
The canal continues along the North branch for about mile
and wo-hirds to lock &c. which with 10 and H. situate
in Old Town." called. Just above the upper end Of
this place the canal carried through thorough cut in slate
rock, about onethrd of mile in length with an average
depth Of about 80 feet 1t then pursues its way again in
sight OF the river to lock H. the entire length of this level
being about n miles,
One mile brings lock No. 49, Immediately above
which the Baltimore and Ohio Railroad, which it will be
remembered crossed the canal and into Virginia at Ha-
pes Ferry, returns to the Maryland Shore and them
again at SO great elevation that is enabled cross two
large bends Of the river and pursue nearly straight line to
the town of Cumberland
In following the canal rise through locks 49, a. and
75 which very each ohe and find ourselves on the
last and highest level Of the canal On this level we cross
portion Of of the bends and at the dis
tance Of five miles reach "Evts Creek, over which the
canal is carried by its eleventh and last aqueduct This
structure has but arch which Of 70 feet span and ID
feet rise in every other respect like the last Three miles
dam No. 8, in the town of Cumberland.
The construction of this dam differs from all the others
No J. from the Maryland shore an island in the river
built Of stone laid dry, with its cross section in the form of an
arch and from the island the Virginia Shore Of brush
sone and gravel No. O. entirely of stone like the frs.
part Of No. No. 8, the Government dam is Of stone
and crib work No. S, and of timber while this
dam No. g. isa massive stone WALL laid in hydraulic cement
and the whole bed for which was excavaed Id f don
the solid rock.
was important to make the whole of this wall water
tight for had been concluded dispense with dam No.
Of the original series he site Of which below the Juno
ton Of the South Banch) till the increase Of trade may rem
der Indispensable became necessary to construct this
dam that particle Of the furnished by the North
Branch and Wills Creek should be lost in dry seasons
the canal must depend for its supply from here down to dam
No. 9, length OF fifty miles, upon what could here be
sured up With this limited supply the navigation was
opened last November when less water had been passing in
these streams for than months than was remember
cd "by the oldest nhabitant"
There are ITO cuvers passing under this canal, 80 Of
which road cuvers OF the whole number $50 are en-
trey of stone laid in hydraulic cement and of them Of
stone with brick arches Most Of them are founded on solid
rock the excavation to reach which was often many feet
The abutmens and piers of the aqueducts are also on rock
some cases only reached deep All the locks
but thirteen entirely of sone with the faces beds and
joints cut hammer dressed the exceptions No. So to
inclusive, of rubble work, with lining of timber and
plank usually called composite locks. Boats carving one
hundred tons and upwards pass freely through all the locks
from Cumberland to Washington, and is in contemplation
carry from l2O to l30 on boats that capacity could
freely pass.