ussion it is desirable to keep them sharply
distinguished. _Objective_ is the end of some particular movement or
operation, and is the special concern of the officer in command. _Object_
is the end of a system of operations and is the special concern of the
general staff or director of the war. An _objective_ is some definite point
which we wish to get from the enemy or prevent his occupying, or some part
of his strength which we wish to destroy. It is incorrect to use the term
of anything we already possess. Thus, Vladivostock is often said to have
been Rojesvensky's _objective_. It was, strictly speaking, only his
_destination_. To reach it and concentrate with the units already there was
the _primary object_ of the operations entrusted to him. He had no true
_objective_ before him except Togo's fleet.

An _objective_ is always subordinate to some _object_. It is a step to the
attainment of that object.

_Lines of Operation_

A line of operation is "the area of land or sea through which we operate
from our base or starting point to reach our objectives."

Lines of operation may be _exterior_ or _interior_. We are said to hold the
_interior_ lines when we hold such a position, in regard to a theatre of
operations, that we can reach its chief objective points, or forces, more
quickly than the enemy can move to their defence or assistance. Such a
position is called an _interior position_. "Exterior Lines" and "Exterior
Positions" are the converse of these.

_Lines of Communication_

This expression is used of three different things:--

(1) _Lines of supply_, running from the base of operations to the point
which the operating force has reached.

(2) _Lines of lateral communication_ by which several forces engaged in
one theatre of operations can communicate with each other and move to
each other's support.

(3) _Lines of retreat_, which are usually lines of supply reversed,
_i.e._, leading back to the base.

For naval purposes these three ideas are best described by the term "lines
of passage and communication," which were in use at the end of the 18th
century, and they may be regarded as those waters over which passes the
normal course of vessels proceeding from the base to the objective or the
force to be supplied.

_Maritime Communications_

The various kinds of Maritime Communications for or against which a fleet
may have to operate are:--

(1) Its own communications, o