carrying about nine thousand guns
and thirty thousand men. Russia, Austria, Prussia, Sweden, and other
continental powers, have but little commerce to be protected, while
their extensive frontiers are greatly exposed to land attacks: their
fortifications and armies, therefore, constitute their principal means
of defence. But for the protection of their own seas from the inroads of
their powerful maritime neighbor, Russia and Austria support naval
establishments of a limited extent. Russia has, in all, some one hundred
and eighty vessels of war, and Austria not quite half that number.[13]

[Footnote 13: These numbers include _all_ vessels of war, whether in
commission, building, or in ordinary.]

The United States possess no colonies; but they have a sea-coast of more
than three thousand miles, with numerous bays, estuaries, and navigable
rivers, which expose our most populous cities to maritime attacks. The
northern land frontier is two thousand miles in extent, and in the west
our territory borders upon the British and Mexican possessions for many
thousand miles more. Within these limits there are numerous tribes of
Indians, who require the watchful care of armed forces to keep them at
peace among themselves as well as with us. Our authorized military
establishment amounts to 7,590 men, and our naval establishment consists
of seventy-seven vessels of all classes, carrying 2,345 guns, and 8,724
men.[14] This is certainly a very small military and naval force for the
defence of so extended and populous a country, especially one whose
political institutions and rapidly-increasing power expose it to the
distrust and jealousy of most other nations.

[Footnote 14: Since these pages were put in the hands of the printer,
the above numbers have been nearly doubled, this increase having been
made with special reference to the present war with Mexico.]

The fortifications for the defence of our sea-coast and land frontiers
will be discussed hereafter.[15]

[Footnote 15: Jomini's work on the Military Art contains many valuable
remarks on this subject of Military Polity: also the writings of
Clausewitz, Dupin, Lloyd, Chambray, Tranchant de Laverne, and Rudtorfer.
Several of these questions are also discussed in Rocquancourt,
Carion-Nisas, De Vernon, and other writers on military history. The
several European Annuaires Militaires, or Army Registers, and the French
and German military periodicals, contain much valuable matter co