DOORWAYS. 371
features alone will be dealt with which are essential and prominent from
the point of view of a dock engineer.
It is manifestly désirable that sheds (and warehouses) should be, as
far as possible, of thoroughly fireproof construction throughout. From
motives of economy, however, the former are often constructed of in-
flammable material, such as timber and zinc. Single-storey sheds are most
noticeable in this respect.
Doorways.—The openings in the sides of a shed, both at the dock front
and along the roadway, should be as numerous as possible, more particularly
in the first case, so as to be adapted for receiving the discharge from several
hatchways simultaneously. It is a good plan to have continuous doors, on
account of the difficulty of getting several ship’s hatchways to coincide with
Figs. 351 and 352.— Wooden Shed Door.
isolated door openings. With this arrangement, the sides of the shed will con-
sist of a series of columns with intervening spaces, generally closed by doors,
but sometimes, as at Havre, without them. At the same time, it must
be remarked that the absence of longitudinal walls causes a shed to lose
much of its stiffness as a structure, and deprives it of the means of affording
lateral support to its contents. Grain discharged in bulk is often prevented
from spreading, on one side at least, by an external wall or partition, with
a consequent saving in space, and similar assistance is rendered in the case
of many other classes of goods. This fact emphasises the necessity for sub-
stantial sides to a shed. The advantages of continuous doorways, moreover,
on the roadside are more imaginary than real. Not more than one-half