ig6 Sir Robert Seppings on a new principle 
The frames of a mercantile ship (on the present mode of 
building) before they are placed and united to each other, 
may be seen in PI. VIII. Fig. 3, with their chocks or wedge- 
pieces. To the evils already stated of the present practice, 
may be added that of imperfect workmanship, so that the 
surfaces of the chocks are seldom in contact with those of 
the timbers ; and the ends of both are frequently reduced so 
thin, as to split by the fastenings that are necessary to secure 
the planks to the ribs; and thus the ship, in the event of 
grounding, or even in the act of rolling, derives little sup- 
port from timbers united only, in fact, by two narrow edges. 
Another great defect arising out of the present plan of 
constructing mercantile ships is, that the ends of the lower 
ribs or timbers, commonly termed the lower futtocks, (PI. 
VIII. Fig. 3. B) are not continued across the keel C, so that 
no support is given in a transverse direction when the ship 
touches the ground ; nor any aid to counteract the constant 
pressure of the mast. This great sacrifice of strength and 
safety is made for no other purpose than that of giving a pas- 
sage for the water to the pumps. 
The floor timbers, which by this mode of construction are 
the only timbers that cross the keel, are also weakened for 
the same purpose, as shown at D, PI. VIII. Fig. 3. This mode 
also makes the conveyance of the water very uncertain, for 
the passage is not unfrequently choaked ; and the pumps 
(from its not being practicable to continue them sufficiently 
down) always leave from 6 to 8 inches of water in the ship ; 
so that these compartments constantly contain a certain quan- 
tity of putrid bilge water, offensive and injurious to the health 
of those on board. 
