SHIP-BUILDING. 
6.5/ 
into three principal pails. 1. To give the 
ihip such an exterior form as may be most 
suitable to the service for which she is de- 
sio-ned. 2. To give the various pieces of a 
siup their proper figure; to assemble and 
unite them into a firm compact frame, so that 
bv their combination and disposition they 
inay form a solid fabric, sufficient to answer 
nil the purposes for which it is intended. 
And, 3- To provide convenient accommo- 
dations for the officers and crew, as well as 
suitable apartments for the cargo, furniture, 
provisions, artillery, and ammunition. 
The exterior figure of a ship may be di- 
vided into the bottom and upper works. The 
bottom, or quick-work, contains what is term- 
ed the hold, and which is under water when 
the ship is laden. The upper works, called 
also the dead-work, comprehend that part 
which is usually above the water when the 
ship is laden. "The figure of the bottom is 
therefore determined by the qualities which 
are necessary for the vessel, and conformable 
to the service for which she is proposed. 
The limits of our design will not admit of 
a minute description and enumeration of all 
(lie pieces of timber which enter into the 
construction of a ship, nor of a particular 
description of their assemblage and union, or 
the maun '>• in which they reciprocally con- 
tribute to the solidity of those floating cita- 
de U is usual among shipwrights to delineate 
three several draughts. 1 . The whole length 
of the ship is represented according to a side 
view, perpendicular to the keel, and is 
termed the plane of elevation, or sheer 
draught. Plate II. fig. 10, 11, the ship is 
exhibited according to an end view, and 
stripped of her planks, so as to present the 
outlines of the principal timbers ; and this is 
properly termed the plane of projection, or 
the vertical plane of the timbers (fig. 12), be- 
cause it shows the projection of their frames 
relatively to each other. 3. It is not suffi- 
cient to have the vertical curves of the bottom 
in different places, for a distinct idea of the 
horizontal curves is also equally necessary 
and useful ; this is obtained by means of 
water-lines, traced upon what is called the 
horizontal plane (fig. 1 1). In this draught 
the curves of the transoms, called the round- 
aft are also marked, and sometimes the 
breadth and thickness of the timbers. 
The plane of elevation (fig. 10), deter- 
mines the length and depth of the keel ; the 
difference of "the draughts of water ; the 
length and projection, or rake, of the stem 
and stern-post ; the position of the midship- 
frame upon the keel, together with that of the 
principal frames afore and abaft; the load- 
water line; the wales; the dimensions and 
situations of the gun-ports; the projection of 
the rails of the head and stern-gallery ; with 
the stations of the masts and channels. 
This draught, however, conveys no idea of 
tlm vertical curve of the ribs or timbers ; for 
as their projection will be only represented 
in a plane elevated upon the length of the 
keel they will appear in this direction no 
otherwise than as straight lines. To perceive 
these curves- accurately, they must be re- 
garded in another point of view ; which will 
represent their projection upon a vertical 
plane supposed to cut the keel at right 
angles’ in the place where the ship is broadest. 
Yon. II. 
For. as all ships are broadest near the middle 
of their lengtn than towards the extremities, 
it is evident that the timbers are more ex- 
tended in proportion. The most capacious 
of these represents what is called the mid- 
ship frame ; and upon the area of this frame 
is delineated the projection of all the others. 
Thus the plane of projection limits the 
different breadths of a ship in various points 
of her length, and exhibits the outline of the 
timbers respectively to each other as they are 
erected upon the keel. Accordingly, this 
draught ought to present a variety of sections 
of the ship in different places of her length, 
and always perpendicular to the surface of 
the water; so that the eye of the observer, 
when placed in w hat may be properly termed 
I the axis of the ship, may perceive the several 
sections at one glance ; that is to say, when 
looking full on the stem from before the ship, 
he shall discover the fore-timbers; and when 
looking from behind, directly to the stern, 
he shall perceive the .form of the after-tim- 
bers. 
To form a just idea of this plane, therefore, 
we ought to suppose a ship resting upon the 
stocks, in the same position as when afloat 
upon the \\ater. Thus a variety of black 
vertical lines may be drawn at equal dis- 
tances upon the bottom, which is white, to 
form different outlines of the ship corres- 
ponding to the timbers within. It is to be 
observed, that the fashion of the inferior tim- 
bers must conform to the figure of the mid- 
ship frame, which is placed in the fullest part 
of the ship ; and as the planes of all the 
other timbers diminish in a certain progres- 
sion as they approach the stem and stern, 
they are properly delineated on the plane of 
the midship-framej which also represents the 
depth of the keel and length of the midship- 
beam. 
As the two sides of a ship ought to be ex- 
actly alike, itis judged sufficient to represent 
the sections of the fore-part of the ship on the 
left side, and those in the after-part on the 
right side, so as to perceive all the sections, 
as well afore as abaft, upon one plane. See 
the Plate, fig. 12. 
However necessary it may be to under- 
stand precisely the vertical curves of the bot- 
tom, it is no less requisite to have a just idea 
of those which are horizontal. 
The horizontal or floor-plane is that upon 
which the whole frame is erected, and will be 
more clearly understood by previously de- 
scribing the water-lines and ribands of which 
it is composed. 
When a ship floats upon the stream, it is 
evident that her upper works will be sepa- 
rated from the bottom by the surface of the 
water, which will accordingly describe an 
imaginary horizontal line upon the bottom 
from the stem to the stern-post. 
The most elevated of those lines is termed 
the load water-line, which is supposed to be 
drawn by the surface of the water on the 
upper part of the bottom, when she is suffi- 
ciently laden for a sea-voyage. For if we 
suppose this surface a rule, and thereby de- 
scribe a corresponding black line along the 
vessel’s bottom, that line will be distinguished 
upon the bottom, which is white, and repre- 
sent what is called the load water-line. 
If the ship is lightened of any part of her 
lading, and preserves the same difference in 
40 
her draught of water at the two ends; or, 
what is the same thing, if she is lightened so 
as to preserve the same equilibrium of the 
keel with regard to the surface ot the water, 
it is evident that she will rise higher out of the 
water, so that the black line already describ- 
ed will be elevated above it; and another 
black line may be delineated upon the bot- 
tom, close to the surface of the water, which 
will exhibit a second water-line parallel to 
the first, but nearer the keel in proportion 
to the number of feet which the ship has 
risen. 
Thus by lightening a ship gradually, and 
at the same time preserving the direction of 
her keel, or the angle which the keel makes 
with the surface of the water, a variety of 
water-lines may be drawn parallel to each 
other, and to the load water-line. 
The ribands are likewise of great utility in 
ship-building ; they are narrow and flexible 
planks placed on the bottom at different 
heights, so as to form a sort of mould for 
stationing the inferior timbers between the 
principal ones. They differ from the water- 
lines, inasmuch as the latter have only one 
curve, which is horizontal ; whereas the 
ribands, besides their horizontal one, have a 
vertical curve. To convey a just idea of 
these curves, which cannot be represented on 
one draught at their full length without an 
oblique section of the ship’s length, it will be 
necessary to have recourse to two planes ; 
that of the elevation, which exhibits their 
vertical curve; and to the floor-plane, upon 
which the horizontal curve is expressed. 
These different lines are extremely useful 
in exhibiting the various curves of a ship’s 
bottom, that, as they are gradually dimi- 
nished, their uniformity or irregularity may 
be discovered by the skilful artist. 
The qualities required in a ship ought to 
determine the figure of the bottom. A ship 
| of war, therefore, should be able to sail 
j swiftly, and carry her lower tier of guns suf- 
! ficiently out of the water ; otherwise a small 
ship will have the advantage of a large one, 
inasmuch as the latter cannot open her lower 
battery in a fresh side-wind without being 
exposed to extreme danger by receiving a 
great quantity of water in at her ports be- 
tween decks. A merchant-ship ought to con - 
tain a large cargo of merchant-goods, and be 
navigated with few hands; and both should 
be able to carry sail firmly, steer well, drive 
little to leeward, and sustain the shocks of 
the sea without being violently strained. 
The first thing to be established in the 
draught of a ship, is her length ; and as a 
ship of war, according to her rate, is fur- 
nished with a certain number of cannon, 
which are placed in battery on her decks, itis 
necessary that a sufficient distance should be 
left between their ports to work the guns 
with facility ; and particularly to leave space 
enough between the foremost guns and the 
stem, and between the aftmost gun and the 
stern-post on each side, on account of the 
arching or inward curve of the ship toward 
her extremities. 
When the length of a ship is determined, 
it is usual to fix her breadth by the dimen- 
sions of the midship-beam. On this occa- 
sion the shipwrights, for the most part, are 
conducted by rules founded on their own ob- 
servation ; for, having remarked, that some 
vessels, which by repeated experience have 
