, expressed graphically by a few lines and a few dots, leads
most certainly to the comprehension of decisive relations in a
military field of action.

In the United States, Pensacola and the Mississippi River have been
rivals for the possession of a navy-yard. The recent decision of a
specially appointed board in favor of the latter, while it commands
the full assent of the writer, by no means eliminates the usefulness
of the former. Taken together, they fulfil a fair requirement of
strategy, sea and land, that operations based upon a national
frontier, which a coast-line is, should not depend upon a single place
only. They are closer together than ideal perfection would wish; too
easily, therefore, to be watched by an enemy without great dispersal
of his force, which Norfolk and New York, for instance, are not; but
still, conjointly, they are the best we can do on that line, having
regard to the draught of water for heavy ships. Key West, an island
lying off the end of the Florida Peninsula, has long been recognized
as the chief, and almost the only, good and defensible anchorage upon
the Strait of Florida, reasonable control of which is indispensable to
water communication between our Atlantic and Gulf seaboards in time of
war. In case of war in the direction of the Caribbean, Key West is the
extreme point now in our possession upon which, granting adequate
fortification, our fleets could rely; and, so used, it would
effectually divert an enemy's force from Pensacola and the
Mississippi. It can never be the ultimate base of operations, as
Pensacola or New Orleans can, because it is an island, a small island,
and has no resources--not even water; but for the daily needs of a
fleet--coal, ammunition, etc.--it can be made most effective. Sixty
miles west of it stands an antiquated fortress on the Dry Tortugas.
These are capable of being made a useful adjunct to Key West, but at
present they scarcely can be so considered. Key West is 550 miles
distant from the mouth of the Mississippi, and 1200 from the Isthmus.

The islands of Santa Lucia and of Martinique have been selected
because they represent the chief positions of, respectively, Great
Britain and France on the outer limits of the general field under
consideration. For the reasons already stated, Grenada, Barbadoes,
Dominica, and the other near British islands are not taken into
account, or rather are considered to be embraced in Santa Lucia, which
adequately repr