, accidents of
time, accidents of place, accidents of ground,--the whole
unforeseeable chapter of incidents which go to form military history.
A military situation is made up of many factors, and before a ship can
be called obsolete, useless to the great general result, it must be
determined that she can contribute no more than zero to either side of
the equation--or of the inequality. From the time she left the hands
of the designers, a unit of maximum value, throughout the period of
her gradual declension, many years will elapse during which a ship
once first-rate will be an object of consideration to friend and foe.
She will wear out like a garment, but she does not necessarily become
obsolete till worn out. It may be added that the indications now are
that radical changes of design are not to be expected shortly, and
that we have reached a type likely to endure. A ship built five years
hence may have various advantages of detail over one now about to be
launched, but the chances are they will not be of a kind that reverse
the odds of battle. This, of course, is only a forecast, not an
assertion; a man who has witnessed the coming and going of the monitor
type will forbear prophecy.

Now, as always, the best ships in the greatest number, as on shore the
best troops in the greatest masses, will be carried as speedily as
possible, and maintained as efficiently as possible, on the front of
operations. But in various directions and at various points behind
that front there are other interests to be subserved, by vessels of
inferior class, as garrisons may be made up wholly or in part of
troops no longer well fitted for the field. But should disaster occur,
or the foe prove unexpectedly strong, the first line of reserved ships
will move forward to fill the gaps, analogous in this to the various
corps of reserved troops who have passed their first youth, with which
the Continental organizations of military service have made us
familiar. This possibility has been recognized so well by modern naval
men that some even have looked for decisive results, not at the hands
of the first and most powerful ships, but from the readiness and
number of those which have passed into the reserve, and will come into
play after the first shock of war. That a reserve force should decide
a doubtful battle or campaign is a frequent military experience--an
instance of superior staying power.

There is no reason, therefore, to worry about a shi