he cognate idea, experiment, underlies scientific advance.

Both history and reasoning, of the character already outlined in these
papers, concur in telling us that control of the sea is exercised by
vessels individually very large for their day, concentrated into
bodies called fleets, stationed at such central points as the
emergency demands. Our predecessors of the past two centuries called
these vessels "ships of the line of battle," from which probably
derives our briefer modern name "battleship," which is appropriate
only if the word "battle" be confined to fleet actions.

Among the naval entities, fleets are at once the most powerful and the
least mobile; yet they are the only really determining elements in
naval war. They are the most powerful, because in them are
concentrated many ships, each of which is extremely strong for
fighting. They are the least mobile, because many ships, which must
keep together, can proceed only at the rate of the slowest among them.
It is natural to ask why not build them all equally fast? The reply
is, it is possible to do so within very narrow limits, but it is not
possible to keep them so. Every deterioration, accident, or adverse
incident, which affects one involves all, as regards speed, though not
as regards fighting force. In our recent war, when an extensive
operation was contemplated, the speed of one battleship reduced the
calculated speed of the fleet by one knot,--one sea mile per hour.
But, it may be urged, will not your slowest speed be much increased,
if every vessel be originally faster? Doubtless; but speed means
tonnage,--part of the ship's weight devoted to engines; and weight, if
given to speed, is taken from other qualities; and if, to increase
speed, you reduce fighting power, you increase something you cannot
certainly hold, at the expense of something at once much more
important and more constant--less liable to impairment. In the
operation just cited the loss of speed was comparatively of little
account; but the question of fighting force upon arrival was serious.

An escape from this dilemma is sought by the advocates of very high
speed for battleships by increasing the size of the individual ship.
If this increase of size is accompanied by increase of speed, but not
proportionately of fighting power, the measure, in the opinion of the
writer, stands self-condemned. But, granting that force gains equally
with speed, there is a further objection already men