were of two general types, truss-framed or bulkhead-framed; all were
flat-bottomed, with a rake of about 45° at bow and stern. The
truss-framed scows were built with a cross-truss every 10 to 15 ft., on
which rested, fore and aft, two classes of beams, main and intermediate.
The main beams were built of timbers ranging from 10 by 10 in. to 14 by
14 in., were scarfed at the joints, and trussed with the bottom logs.
The intermediate beams were of timbers varying from 6 by 6 in. to 10 by
12 in., had butt joints, and were dapped at the cross-trusses to give a
convex surface to the deck, which was built of 3-in. and 4-in. plank,
from 8 to 12 in. in width, running athwartship. The sides of the scows
of this class were spiked and bolted to trusses similar to those running
under the main beams. The bulkheaded boats had both sides and two
longitudinal bulkheads placed so as to divide the scow into three
sections of equal width, built of 8 by 8-in. or 10 by 10-in. timbers,
laid one upon the other, and bolted through from top to bottom. The
beams on these boats ran athwartship, rested on sides and bulkheads, and
ranged from 6 by 10-in. to 10 by 12-in., spaced 2 ft. apart, and dressed
to give a convex surface to the deck, which was usually 3 in., in some
cases 4 in., in thickness, and made up of narrow plank from 4 to 6 in.
in width.

[Illustration:
Fig. 11.
DIAGRAM OF DECK SHOWING BAYS]

These boats had all been designed for lighter work than they were here
required to perform, and a large amount of breakage occurred from the
start. In order that the contractors for the excavation should be
unhampered as to method of loading, the contracts provided that they
should pay for all damage done to the scows in loading, other than