BARREL-BULK. A measure of capacity for freight in a ship, equal to five
cubic feet: so that eight barrel-bulk are equal to one ton measurement.

BARREL-SCREW. A powerful machine, consisting of two large poppets, or
male screws, moved by levers in their heads, upon a bank of plank, with
a female screw at each end. It is of great use in starting a launch.

BARRICADE. A strong wooden rail, supported by stanchions extending as a
fence across the foremost part of the quarter-deck, on the top of which
some of the seamen's hammocks are usually stowed in time of battle. In a
vessel of war the vacant spaces between the stanchions are commonly
filled with rope-mats, cork, or pieces of old cable; and the upper part,
which contains a double rope-netting above the sail, is stuffed with
full hammocks to intercept small shot in the time of battle. Also, a
temporary fortification or fence made with abatis, palisades, or any
obstacles, to bar the approach of an enemy by a given avenue.

BARRIER OF ICE. Ice stretching from the land-ice to the sea or main ice,
or across a channel, so as to render it impassable.

BARRIER REEFS. Coral reefs that either extend in straight lines in front
of the shores of a continent or large island, or encircle smaller isles,
in both cases being separated from the land by a channel of water.
Barrier reefs in New South Wales, the Bermudas, Laccadives, Maldives,
&c.

BARRIERS. A martial exercise of men armed with short swords, within
certain railings which separated them from the spectators. It has long
been discontinued in England.

BARROW. A hillock, a tumulus.

BARSE. The common river-perch.

BARTIZAN. The overhanging turrets on a battlement.

BARUTH. An Indian measure, with a corresponding weight of 3-1/2 lbs.
avoirdupois.

BASE. The breech of a gun. Also, the lowest part of the perimeter of a
geometrical figure. When applied to a delta it is that edge of it which
is washed by the sea, or recipient of the deltic branches. Also, the
lowest part of a mountain or chain of mountains. Also, the level line on
which any work stands, as the foot of a pillar. Also, an old boat-gun; a
wall-piece on the musketoon principle, carrying a five-ounce ball.

BASE-LINE. In strategy, the line joining the various points of a base of
operations. In surveying, the base on which the triangulation is
founded.

BASE OF OPERATIONS. In strategy, one or a series of strategic points at
which are established the magazine