nautical technology 159
shell structure. About the turn of the sixth century ce, wrecks found in Dor Lagoon
along the Israeli coastline demonstrate changes in hulls: they are now geometrically
shaped by transverse frames nailed to the keel in a quasi-systematic way, thus acting as
a sort of a “skeleton;” planking is attached to each frame by iron nails. Because of the
disappearance of the mortise-and-tenon joint that rendered the hull waterproof, the
seams were sealed with threads of oakum (Pomey et al., 2012).
However, other wrecks found in both basins of the Mediterranean and dating
between the fifth century and 1000 point to a non-linear progression in ship design
and to a complicated transitional evolution with different regional traditions of con-
struction over the next 500 years (Pomey et al., 2012). On the other hand, data from
a sequence of wrecks clearly indicate that the eleventh-century Serçe Limanı wreck
(south-western Turkey) provides the terminus post quem for the “frame-based”
Mediterranean hull design, the only one practiced in the Mediterranean since the
early second millennium ce (Hamelink, 2004; Pryor and Jeffreys, 2006: 147).
Technologically and economically speaking, the frame-base assembly system
required less material than the previous shell-based one, and the manpower could
have been less “professional.” The entire process was much faster and cheaper, and
maintenance was easier and less costly. Probably the decrease in Mediterranean
economic activity following the gradual decline of the Roman Empire spurred this
transition. Large Roman ships of over 100 tons disappeared and, instead, medium-
sized ships of 50–60 tons were common (Mor, 2012). Ironically, despite the revival
of the Mediterranean economy from the eleventh century onwards (see Valérian, this
volume), this new ship design was generally adopted and diffused.
Comprehensive deconstruction of medieval wrecked hulls reveals that the floor-
timbers and tail-frames that began manifesting the shapes of the vessel were most
likely designed with adjustable molds. This set of molds may have been used to pre-
determine the heights, widths and curves. The distribution of the floor-timbers and
tail-frames in each ship yielded a hull that was segregated into six sections: one section
in the bow and stern beyond each tail-frame, and the remaining four within the cen-
tral body of the ship. This method is defined as the proto master-frame. The process
of manifesting vessel shape through a six-part division of the hull is also evident in
written sources, the earliest being the thirteenth-century manuscript of Constantinos
Euteles Anagnostes of Cyprus regarding determination of the tonnage in kouphia,
before assembly was completed. This indicates that shipwrights may have possessed
sets of molds for vessels of specific capacities (Harpster, 2010: 50–51). The next evi-
dence comprises thirteenth- and early fourteenth-century northern Italian decrees
that mainly applied to galley construction, and contracts in the Angevin registers,
regarding the taride, the horse carriers, intended in 1246 for the fleet of King Louis
IX of France as well as for the bireme war galleys intended for the fleet of Charles of
Anjou in 1275 (Pryor, 1994: 59).
Based on marine archaeological and written evidence, some scholars argue for the
introduction of eastern Mediterranean–Byzantine shipbuilding designs to southern
Italy and Venice, pointing to the Greek vocabulary of technical terms regarding ships’
components and methods of hull construction found in the Venetian texts.
Furthermore, the Arsenal hierarchy under a protomaestro reflects the Byzantine hier-
archy under a protomaistor. According to this theory, Byzantine shipwrights might
have introduced their methods into Venetian naval architecture quite early (Alertz,