SHIP BUI 
frame ioint is 5 feet 6 inches ; and it is at 
each of these stations that perpendiculars 
from the keel are drawn in the sheer plan: 
the timbers before 0 are alphabetically 
npmed A, B, C, &c. ; and those abaft 0, 
or dead flat, numerally, 1, 2, 3, &c. ’Ihe 
timbers adjoining 0, which have no rising, 
are distinguished thus (A) (B), or (1) (2), 
and are likewise called flats. 
In this ship 0 is a single timber, although 
it has been before observed this single tim- 
ber is sometimes placed near the steps, or 
gangway. Observe, this single timber is in- 
troduced to change the bodies, as that be- 
fore it is called the fore-body, so that abaft it 
is called the after-body i but this is not all, 
the floors in the fore-body are placed on 
the fore-side of the joint, consequently their 
moulding edge is on their aft-sidp, and the 
floors in the after-body are placed on the 
aftside the joint, and their moulding edge is 
on their foreside 5 therefore in both bodies 
they become under bevellings : hence the 
necessity of this single timber to effect this 
change, or two floors would come together 
at the turn of the body, and the joint at 
their heads not strengthened by this inter- 
mediate shift of timber. 
Now, as we do not mean to square up 
perpendiculars at the joint of every frame 
timber, we shall make use of as many as will 
suit our purpose in delineating the sheer 
plan. Therefore set before the perpendicu- 
lar 0 19 feet 3 inches, and then square up 
from the upper edge of the keel a perpen- 
dicular, and under it mark F, as that is the 
station for frame F ; then before F square 
up perpendiculars at 11 feet distant, marking 
under that next F, K, the next O, and the 
foremost one S. Then abaft the perpendi- 
cular 0 set off 24 feet 9 inches, and then 
square up a perpendicular, and mark under 
it 6, as that will be the station for frame 6 ; 
then abaft this perpendicular set off 16 feet 
6 inches five times, and square up perpen- 
diculars at each station, marking that next 
abaft 6, 12, the others in succession 18, 24, 
30, and the after one 36. These perpendi- 
culars, or stations, are always referred to by 
those names hereafter. 
Above the upper edge of the rabbit of the 
keel set up upon the foremost perpendicu- 
lar 29 feet, the height of breadth at the stem, 
as both heights of breadths are terminated 
at one place quite forward aud aft; next 
set up at S 24 feet 2 inches ; at O, 22 feet 
8 inches ; at K, 21 feet 10 inches ; at F, 21 
feet 3 inches; at 0, 21 feet 3 inches; at 
6, 21 feet 3jf inches ; at 12, 21 feet 4 inches ; 
at 18, 21 feet 6 inches ; at 24, 22 feet 4 
inches; at 30j 23 feet 9 inches; at 36, 26 
feet 5 inches; and the after perpendicular, 
27 feet 10 inches. Then an elliptical curve 
drawn through those heights will show the 
lower height of breadth all fore and aft. 
The rising line is the next curve to be 
drawn in the sheer plan, which in a ship of 
this construction gives the heights of the 
centres of the floor sweeps, by the which 
curves the shape of the timbers at and near 
the floor heads are formed in the body plan ; 
thus, set up, as before, at K 21 feet 4 in- 
ches ; at F, 14 feet 7 inches ; at 0, 11 feet 
6 inches; at 6, 12 feet; at 12, 14 feet; at 
18, 17 feet 6 inches; and at 24, 24 feet 11 
inches. 
Then an elliptical curve drawn through 
those heights will determine the centre 
heights of the floor sweeps, and although 
these lines may be termed imaginary lines, 
and not waftted in finishing the fabric, the 
necessity of drawing these lines, with their 
connected half breadths, &c. will appear, 
when we insist upon the nicety required in 
the formation of every line used in ship- 
building; and by thus representing them, 
the draftsman, or constructor, avails himself 
of an opportunity of observing that the said 
lines make fair curves. We said above, that 
the rising line in a ship of this construction 
gave the heights of the centres for forming 
the floor-sweeps ; but in full-built ships, or 
merchant ships in general, this rising line 
gives the rising or lifting of the floors to- 
wards their heads, above which one radius 
is given for limiting their curves, and from 
this very line the whole construction or 
form of the body at this place is given. 
Now, in the formation of this line, no unde- 
viating rule is given; therefore, to construct 
it, a general knowledge of the formation of 
various bodies of different vessels is abso- 
lutely necessary. But what follows may be 
unvariably observed, that is the lifting of 
this line on the sheer plan, and narrowing 
it on the half-breadth plan, will procure ve- 
locity and less capacity ; while lowering it 
on the sheer plan, and continuing its mid- 
ship part parallel with the keel, and aug- 
menting its breadth on the half breadth, and 
continuing it in midships parallel with the 
middle line, will produce a full, or burthen- 
some vessel ; but then a vessel on this con- 
struction will not sail; hence the judgment 
required in constructing this part of the ship 
can only be acquired by practice. 
Now the main half-breadth, and the half- 
breadth of the rising of this ship, may be 
