- Celtic Seafaring and Transport -
medieval proto-Viking tradition of northern Europe (McGrail 198 Ia: 23-4). Some of
the boats in this group do have anomalous features: for example Zwammerdam 2 and
6 have some overlapping planking fastened by nails, comparable with proto-Viking
techniques; whilst Zwammerdam 6 also has flush-laid planking fastened by loose-
tongue joints similar to those in the Mediterranean tradition; and Zwammerdam 6
and Pommeroeul 5 have flush-laid planking fastened by obliquely driven spikes (de
Weerd 1988; de Boe and Hubert 1977). Nevertheless, in all the boats of this group,
the greater part of the planking is flush-laid and is not edge-joined, but fastened to
the heavy framing timbers by large iron nails clenched by turning the point back
through 180° so that it re-enters the frame.
This strongly suggests that these boats and ships were built in the skeleton
sequence, possibly the earliest known use of this technique in the building of plank
boats. Arnold (1992) has, however, argued that boats of this tradition designed for
use on inland waters (in particular those from Yverdon and Bevaix, Switzerland)
were neither skeleton nor shell construction, but 'bottom-based construction'. It is
true that shell and skeleton concepts are more difficult to apply to barge-like boats
with flat-bottomed transverse sections and hard chines, than to round-hulled vessels;
and it is also true, as Arnold says, that 'the flat bottom constitutes a base for the
entire construction'. However, the shape of the sides of such a boat is determined
either by the shape of the first side strakes (the side timbers subsequently conform-
ing to that shape), in which case the shell sequence has been used; or initially by the
shape of the floor-timber ends and subsequently by the side timbers (the planking
conforming to this shape), in which case the skeleton sequence has been used. Which
of these two sequences was used is not clear from the publications of the great
majority of boats in this tradition, but it is clear for the ship Blackfriars I (Figure
15.8) (Marsden 1991): floor timbers were fastened to the two longitudinal planks
forming the keel of this ship, and the shape of the hull (full form with rounded bilges)
was determined by these floors and by the subsequently erected side framing - thus
Blackfriars I was built in the skeleton sequence, as also probably was the Romano-
Celtic ship from St Peter Port, Guernsey (Rule 1990).
The idea of using a framework or skeleton to give the form of a boat had been
familiar to north-west European hide-boat builders from prehistoric times (McGrail
1987: 173-86). To transfer this technique to the building of plank boats and ships may
well have been a major contribution by the Celts to nautical technology. There are,
however, those who would not give the name 'Celtic' to this distinctive type of
boatbuilding: see, for example, Parker (199 I); and Haywood (199 I: 17-2 I) has argued
that, by the second and third centuries AD, the land near the Rhine mouth, where
several of these boats were excavated, was occupied by Germanic tribes. Nevertheless,
most of these boats were excavated from regions which were undoubtedly occupied
by Celts at the date attributed to the boats. Furthermore, the general similarity
between Caesar's description of the Veneti vessels and features of the Blackfriars I and
St Peter Port ships is undeniable. It does not therefore seem unreasonable to call this
tradition 'Celtic' although perhaps 'Romano-Celtic' (or 'Gallo-Roman' to Franco-
phones) is to be preferred, as the nucleus of the boats and ships of this tradition are of
Roman date; moreover, this term draws attention to the possibility of some Roman
technological influence on this Celtic tradition.