The Sun.
London, England, 1864-08-23 00:00:00

Mobile and its Defences.

The following description of the military and
naval defences of Mobile is given by the New York
World:—

"From the Gu!f of Mexico there are three chan-
nels into the harbour of Mobile, two of them (the
most easterly) being defended by Fcrt Morgan, while
the western one is fu:ly garrisoned hr a casemate.
work known as Fort Gaines. The Swesh channel,
which is the principal one by which vessels of any
size can enter the bay, runs directly under the guns
of Fort Morgan, and it is by this channel that nearly
all the blockade runners go in and out of the ha
bout. In strong breezps the sea on the bar is h 0
heavy that it is dangerous to atte•npt its crossi:v.
To aid in the defttice of the bay, and prevent the
Union fleet from passing by the tons, a chain of
obstructions have long since :ken placed seines the
channels. They consist of a row of strong spilt-,s
driven firmly
into the mud. When the tide is at
havelowest
theobstructionsvisible. alo water
been are
dr
the channel line, and on either side of the entrance
to the river bearing that name,
so that it would be
a difficult matter for a vessel unaccompanied by a.
thoroughly-versed pilot to reach the city of Mobil's,
even if she should succeed in pluming
the
sloop, laden with stones, rides at anchor at the
t ea.g os A
of
en-
trance of these obstructions, and at thefira forts,
• successful invasion on the part of an enemy would
he scuttled and sunk, so as to prevent vessels
pass.
ing through the obstructions. The entr ante to
Mobile Bay is between Mobile Point and the eastern
point of Dauphin Island, and the intervening dis-
tance is about three and a quarter miles: The in.
terior of the bay has depth of water sufficient for any
vessel that can cross the bar, which has about 15
feet upon it at low water. On account of a bar
formed opposite the mouth of Dog River, vessels
drawing more than eight or nine feet cannot, at
low water, go further up the bar. The bay of
Mobile is about 30 miles in length from north to
south, with an average width of from ib to 12 miles,
e.eppt where it expands on the south.sart into the
subsidiary bay of Bon Secours, which extends some
eight or ten miles further to the eastward. The bay,
in addition to the outlets elsewhere described., has
one at Grant's Pass, north of Dauphin Island,
which communicates with Mississippi Sound.
Through this channel steamers and other vessels of
light draft formerly passed when plying between
Mobile and New Orleans. The whole upper por-
tion of the bay is shallow, and is supposed to be
gradually filling up with sedimentary deposits from
the rivers which flow into it. Measures were in
progress in 1860.61 for opening a channel to the
city of Mobile for larger vessels than had pre-
viously gone up there. Strong lines of entrench-
ments have been thrown up, encircling the city
from near Dog River around to the Alabama Myer,
and no less than twJve large independent earth-
works have been constructed in rear of the Him of
entrenchments. On Point Pintos is a nine-gun. bat-
tery commanding the line of entrenchments and
one of the channels approaching the city. At Gar-
rows Bend is a five-gun battery, also commas iding
the obstructions and the main ship channel for a
distance of nearly three miles. The rema iniag
earthworks in the vicinity of the city are intended
more particularly to repulse a landing of troops on
the western shores, or a land attack which could be
made at Porterville from the Mississippi Sound,
marching thence up the road to Spring-hill. The
entrenchments are about 15 miles in length, and
were built some time ago. At various points
signal guns and carronades have been mount ad, so
that they can throw grape and cannister among
an advancing foe. A met of marshy lan.d has
been made solid by means of spiles and earth,
and on this has been erected a case!) sated
battery, mounting ten most powerful guns,
viz., three 100-pounder rifles, four 9.in. Dahlg rens,
and three long 32-pounders. Between the Nrareh
battery and the Alabama river, and near the Itttter,
is a redoubt which sweeps the level plateau over
which it keeps guard, and it commands as well a
portion of the bay. Passing further to the tenth-
ward, another redcubt is met near a small village
on the railroad, which mounts four heavy guns. At
Three Mile Creek is another redoubt which guards
the railroad bridge, To the west of Mobile a:a a
series of earthworks several miles in extent, further
defended by formidable breastworks and rifle-pits,
extending from the Shell-road' entirely round the
city to the river. Between the Alabama river and
the Shell-road a sixegun battery commands the
position. Fort Morgan, the main protection to the
city, or rather the entrance to the bay is situated
on Mobile Point. It cost the United States Go.
vernment in its construction 1,500,000 dollars, and
is capable of mounting 132 guns, and of garrison ing
700 men for siege operations. It is built upon the
site of old Fort Boyer, which was noted for its suc-
cessful resistance to a British fleet on the 14th of
September, 1814. The old fort was a:small redoubt
with an armament of 20 abort carronades, and gar.
risoned by only 120 men all told. The Federal
fleet, under the command of Admiral Farragut,
consists of 19 wooden ships, powerful, and with
very heavy batteries, and four of the best of our
monitor ironelads, with five small tugs to act as
despatch vessels, being a total of 28 vessels. The
people will expect much of Admiral Farragut, but
we- must impress upon them the magnitude of the
wti--rk before him, and that the odds are by far in
favour of the rebel defences. It is probable that
some mortar vessels have been added to this truly
formidable fleet, and that a number of troops will be
sent from New Orleans to occupy such places as
Farragut may succeed in capturing."