GRAIN AND RICE

395

load a cargo of grain in bulk a temporary midship longitudinal bulkhead
must be constructed, extending from one end of the hold to the other
and from the bottom up to the deck The bulkhead is made of deal
planks laid fore and aft, edge on edge, so that it forms a boarded parti-
tion dividing the hold longitudinally into two parts. Some ships have
the midship pillars staggered on alternate frames so that the planks
may be rove between them.
Ships engaged frequently in the bulk grain trade have steel midship
longitudinal bulkheads in the lower hold.
A temporary box-shaped feeder must be built in the hatchway;
it is also made of deals standing on their ends and reaching from the
'tween deck to the mam deck hatch coamings, the whole being tomed
ofE from the ship's side, or braced together with wire stays, and backed
up with grain in bags to keep the box feeder firmly in position. The
cubic capacity of a feeder should be large enough to contain from 2 to
6 per cent, of the quantity of gram in the cargo space it is designed to
feed.
The grain is pumped out of the ship by elevators and stored in
specially constructed granaries at those ports which specialise in its
storage, so that it is not touched by hand at all.
Rice is an expensive cargo to carry as the holds have to be fitted up
with an elaborate system of ventilation on the principle of a drainage
scheme, so that air may pass freely throughout the whole cargo. The
ventilators are box-shaped and made of two planks of wood kept about
8 inches distance apart by pieces of wood They are laid fore and
aft on top of a tier of bags from bulkhead to bulkhead and also athwart-
ships from side to side. These fore-and-aft and cross ventilators are
laid horizontally on a tier of bags and spaced five bags apart, and they
communicate with a series of vertical vents extending from the ceiliag
to the top deck. This horizontal system is laid at every third tier
of bags. In addition to all this the side battens and bulkheads are
covered with sticks or bamboos tied criss-cross or lattice fashion and
all bare iron and dunnage is covered with rush mats.
The purpose aimed at is to secure a current of air through the cargo
to carry away the carbonic acid gas given ofE by the rice and also to keep
the hold from sweating. An air space is left between the top tier of
bags and the underside of the deck and also round the inside of the
hatch coamings. During the latter part of the rice season when the