ever may be its
defects, it is nevertheless certain that it would afford immense
advantages to an army intended to operate on the Rhine. Indeed, the
inconvenience of intrenched camps on large rivers is that they are only
very useful when beyond the river; and in this case they are exposed to
the dangers arising from destruction of bridges (as happened to Napoleon
at Essling,)--to say nothing of the danger of losing their provisions
and munitions, or even of a front attack against which the works might
not avail. The system of detached permanent works of Coblentz has the
advantage of avoiding these dangers, by protecting the depots on the
same bank as the army, and in guaranteeing to the army freedom from
attack at least until the bridges be re-established. If the city were
upon the right bank of the Rhine, and there were only an intrenched camp
of field-works on the left bank, there would be no certainty of security
either for the depots or the army. So, if Coblentz were a good ordinary
fortress without detached forts, a large army could not so readily make
it a place of refuge, nor would there be such facilities for debouching
from it in the presence of an enemy. The fortress of Ehrenbreitstein,
which is intended to protect Coblentz on the right bank, is so difficult
of access that it would be quite easy to blockade it, and the egress of
a force of any magnitude might be vigorously disputed.

Much has been recently said of a new system used by the Archduke
Maximilian to fortify the intrenched camp of Linz,--by masonry towers.
As I only know of it by hearsay and the description by Captain Allard in
the _Spectateur Militaire_, I cannot discuss it thoroughly. I only know
that the system of towers used at Genoa by the skillful Colonel Andreis
appeared to me to be useful, but still susceptible of
improvements,--which the archduke seems to have added. We are told that
the towers of Linz, situated in ditches and covered by the glacis, have
the advantage of giving a concentrated horizontal fire and of being
sheltered from the direct shot of the enemy. Such towers, if well
flanked and connected by a parapet, may make a very advantageous
camp,--always, however, with some of the inconveniences of closed lines.
If the towers are isolated, and the intervals carefully covered by
field-works, (to be thrown up when required,) they will make a camp
preferable to one covered by ordinary redoubts, but not so advantageous
as afforded by t