he large detached forts of Coblentz. These towers number
thirty-two, eight of which are on the left bank, with a square fort
commanding the Perlingsberg. Of these twenty-four on the right bank,
some seven or eight are only half-towers. The circumference of this line
is about twelve miles. The towers are between five hundred and six
hundred yards apart, and will be connected, in case of war, by a
palisaded covered way. They are of masonry, of three tiers of guns, with
a barbette battery which is the principal defense, mounting eleven
twenty-four pounders. Two howitzers are placed in the upper tier. Those
towers are placed in a wide and deep ditch, the _deblais_ of which forms
a high glacis which protects the tower from direct shot; but I should
think it would be difficult to protect the artillery from direct fire.

Some say that this has cost about three-fourths of what a complete
bastioned enceinte, necessary to make Linz a fortress of the first rank,
would have cost; others maintain that it has not cost more than a
quarter as much as a bastioned work, and that it subserves, besides, an
entirely different object. If these works are to resist a regular siege,
they are certainly very defective; but, regarded as an intrenched camp
to give refuge and an outlet upon both banks of the Danube for a large
army, they are appropriate, and would be of great importance in a war
like that of 1809, and, if existing then, would probably have saved the
capital.

To complete a grand system, it would perhaps have been better to
encircle Linz with a regular bastioned line, and then to have built
seven or eight towers between the eastern salient and the mouth of the
Traun, within a direct distance of about two and a half miles, so as to
have included for the camp only the curved space between Linz, the
Traun, and the Danube. Then the double advantage of a fortress of the
first rank and a camp under its guns would have been united, and, even
if not quite so large, would have answered for a large army,
particularly if the eight towers on the left bank and the fort of
Perlingsberg had been preserved.

TETES DE PONTS.

_Tetes de ponts_ are the most important of all field-works. The
difficulties of crossing a river, particularly a large one, in the face
of the enemy, demonstrate abundantly the immense utility of such works,
which can be less easily dispensed with than intrenched camps, since if
the bridges are safe an army is insured from t