The Sun.
London, England, 1832-10-04 00:00:00

MILITARY TOPOGRAPHY OF OPORTO,

The city of Oporto, upon which the eyes of all Europe
are at present fixed, is situated near the mouth of the
river Douro, and contains about 70,000 inhabitants. It
is built o❑ the declivity of a mountain, the height of
which is from 35 to 40 wises, and occupies the inclined
plane that extends from the summit to the very edge of the
water. The Douro is both deep and rapid, and about 300
yards wide. A bridge of boats connects it with the suburb
of Villa Nova. The city, from its locale, is extremely
narrow. A convent (de Serra), which commands the fau_
bourg and the city, occupies a mountain equal i❑ height
to that on which Oporto is built. Three routes blanch
off from the city ; one northwards, to Broja ; a second to
Arnarante, eastwards; and the third to the southward,
through Coimura, to the capital. All these are bad, hilly,
and rocky, and unfavourable to the evolutions of cavalry
and artillery,
Oporto is undefended on the north and east sides. On
the south it is covered by the Douro, and on the west by
the ocean and by the forts constructed at the mouth of the
river,

The present line of defence is much more contracted
than that occupied by the Portuguese in 1809. It extends
from t:,e Seminario to the Torre da Maria on the left.
There are thus a position of 50 pieces of artillery, and some
mortar batteries, besides a train of 15 field pieces, ready
to move at a moment's notice. Barricades are erected at
the head of each street, defended by a trench externally,
with a platform for a gun on the inner side, and a breast-
work for infantry. On the Villa Nova side works have
been erected, and the convent de Serra is placed in a pos-
ture of defence, Videttes on this side are thrown forward
as far as St. Ovidio, Don Pedro's force consists of about
14,000 men, one half of which are of the line ; but his
defences would offer no material obstacle to a regular at-
tack. Miguel has about 16,000 or 18,000 men on the
north side of the Douro, and about 6,000 on the south
side. This latter corps has some very heavy artillery. On
the other hand, every thing that could cover the ad-
vance of an enemy in front of Oporto has been levelled and
the population disarmed.
Vallcnga, the scene of the affair of the 23d of July, is a
small villa, about three leagues from Oporto. Amarante,
the head-quarters of the Miguelites, is a very strong posi-
tion ; it is a small place, fortified in the ancient manner,
but possesses a double tete de ponte from the Tamegan, a
small river that disembogues itself into the Douro.—
General St. Martha, unable to make any attempt by the
Coimbra road, because he would have been obliged to cross
the Douro, and nut being master of t be sea, he could make
no demonstration on the west, seized Amarante, while the
reinforcements advancing from the capital would menace
the city on the south side.

Don Pedio's position, in a military point of view, is
extremely critical ; for if he only executes a day's march,
either to the north or the south, he leaves Oporto unco-
vered, and abandons his communications with the sea, by
which he draws all his supplies. His only resource
would be to ascend the river, and attack the Royalist po-
sitions, but they are uncommonly strong, and it took Loi-
son's corps of 7,000 men near an entire month to master
them.

If Dun Pedro is allowed to take up his winter quarter
at Oporto, and to organise his resources for the next cam-
paign, he way yet succeed. Magazine.