auphine and Pelican islands.
Both reports give to that anchorage 18 feet at low water and 20-1/2 at
high. The only difference between them consists in this, that in the
first a bar leading to the anchorage, reducing the depth of water to
12 feet at low tide, was omitted. In neither case could frigates enter,
though sloops of war of larger size might. The whole scope, however, of
this reasoning turns on a different principle--on the works necessary to
defend that bay and, by means thereof, New Orleans, the Mississippi, and
all the surrounding country against a powerful invasion both by land and
sea, and not on the precise depth of water in any of the approaches to
the bay or to the island.

The reasoning which is applicable to the works near New Orleans and at
the bay of Mobile is equally so in certain respects to those which are
to be erected for the defense of all the bays and rivers along the other
parts of the coast. All those works are also erected on a greater scale
than would be necessary for the sole purpose of preventing the passage
of our inlets by large ships of war. They are in most instances formed
for defense against a more powerful invasion, both by land and sea.
There are, however, some differences between the works which are deemed
necessary in the Gulf and those in other parts of our Union, founded on
the peculiar situation of that part of the coast. The vast extent of
the Mississippi, the great outlet and channel of commerce for so many
States, all of which may be affected by the seizure of that city, or
of any part of the river to a great extent above it, is one of those
striking peculiarities which require particular provision. The thinness
of the population near the city, making it necessary that the force
requisite for its defense should be called from distant parts and
States, is another. The danger which the army assembled at New Orleans
would be exposed to of being cut off in case the enemy should throw a
force on the river above it, from the difficulty of ascending the river
to attack it and of making a retreat in any other direction, is a third.
For an attack on the city of New Orleans, Mobile Bay, or any part of the
intermediate coast ships of war would be necessary only as a convoy to
protect the transports against a naval force on their passage, and on
their approach to the shore for the landing of the men, and on their
return home in case they should be repulsed.

On the important subject