ways existed.

This method of blockade is far more difficult to carry out in the present
day, than formerly; owing to the existence of submarines and torpedo craft,
the blockading ships have to remain further away from the port; there have
to be inner lines of cruisers, scouts and destroyers; and quick
concentration takes longer owing to the greater space covered by the
blockading force, and more ships of all natures are required for the same
reason.

Greater and more vigilance are required than in former days, because the
enemy's ships can come out regardless of weather (thick weather would be
their opportunity), and it is most important that not a single craft, from
a battleship to a torpedo boat, be allowed to escape.

This method of blockade includes the commercial blockade, and all countries
would be informed of its having been established.

(2) _Commercial Blockade._--To prevent floating commerce from entering or
leaving the blockaded harbour. The blockading force would not be powerful
enough to prevent a squadron of battleships or cruisers from entering or
leaving the port blockaded; and it would not be instituted outside a
fortified military port, or one containing a strong naval force. But it
would be able to stop scouts and torpedo craft from entering or emerging,
unless in very great numbers; and if unable to stop them from emerging,
would give warning of their escape and the direction in which they are
going.

In both these forms of blockade it is usual, as a matter of courtesy, to
allow neutral armed ships belonging to foreign navies to enter and leave
for their own purposes, presumably connected with the subjects of their own
country who are in the blockaded port. This, however, is not a right, and
the country to which the blockading ships belong has a right to refuse it,
and to back her refusal by force.

All countries must be notified of a properly instituted commercial
blockade, in accordance with International Agreement.

(3) _Observing a Port._--This, with its subsidiary operations, should be
conducted in such a way as to induce the enemy to put to sea, the object of
observing the port being primarily a naval one, viz., to bring him to
decisive action.

The principal observing force (consisting of battleships and cruisers)
would be either in one squadron, or more, provided that they were in
supporting reach of each other, and so placed as to be able to cut off the
enemy's fleet on emerging fr