6 Indications of continuity
Paintings and models hint towards continuity in characteristics like the general shape of the hull, the high and wide forward deck area, the small and low stern, the short spritsail mast tilted forward and the rounded deckhouse in the middle giving access to the fish well and living quarters. The archaeological data set additionally indicates that:
- the internal layout of the ship did not change;
- the rigging and handling equipment on deck like winches, fife rails and bitts, show no signs of significant change over time in form, fit or function;
- the medieval hull shape remains unchanged;
- stability characteristics did not critically change;
- local shipbuilding traditions were followed.
The internal layout of the watership and the equipment on deck did not change over time. This is apparent from a scan through the wreck data, and can be visualised when the archaeological models (fig. 2) are compared to an early 19th century model of the watership (fig. 11).
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Figure 11 Shipmodel of a Marker watership from around 1800. Characteristic is the high bluff bow, the low stern, the rounded deckhouse and the short spritsail mast tilted forward with rounded mast top. (Collection Maritime Museum Rotterdam model M199).
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Optical difference is the rounded deckhouse which is not present in the archaeological models, as it was not found in the associated wrecks either. However the layout did not change i.e. a forward storage and work space, a fish well area, a living area (two bunks and a stove), an aft storage and workspace. The deck equipment may have incidentally changed position, but from a technical and operational point of view it was essentially the same equipment indicating that technology and working procedures did not substantially change over time (OW10, ZK47, ZM22, ZO69). Even the early nineteenth century watership models still featured the specific cleats needed to tie the long trawl net poles to the ships hull during trawling operations (fig. 6, fig. 14). Indications of change in living and working conditions on board were also not found when sifting through archives of seventeenth and eighteenth centuries watership inventories. They did not reveal any time-related changes suggesting a change in design or function (van Holk 1994).
The models (fig. 2, fig. 11) show a sharp underwater hull fore and aft while in between there is very little deadrise. From the keel upward the rounded underwater hull is curved in an S-shape. This is a medieval underwater hull shape typical for the cog-like ships of the Hanse period. The cog design disappeared in the Early Modern period. There was a tendency in the Zuiderzee area to resort to flat bottomed ships with side-mounted retractable leeboards. The watership however retained the medieval hull shape over its life trajectory.
Another indication of continuity is revealed via a study on stability characteristics of the watership (Folkersma 1987). These characteristics relate to the vital concern that a ship will not sink or falter if heavily loaded or pushed on its side by sail and waves. The study concluded, based on the well-documented and reconstructed wreck OW10, that the metacentric height of the watership meets more than twice the present-day requirement of trawl fishing vessels, even without ballast and water on board. This made the ship very stable in the mindset of today. The OW10 weighted 52 ton of which 10 ton is attributed to ballast stones. The ballast served three purposes. First it helped to increase the draft of the ship, thus allowing the fish well to be filled completely with water. Secondly it helped to trim the ship in such a way that the rudder had enough water pressure for steering. The ship was difficult to control if the ballast was not on board while sailing. Finally the stones helped relieve the material stress in the fish well area which had relatively little longitudinal strength. The stones were not needed for sufficient stability, contrary to what is intuitively thought. Compared to the OW10, the other watership wrecks in the design analysis did not vary that much in hull form and construction that buoyancy and stability were at risk. It is safe to assume that in this respect the design did not significantly change over time.
In maritime archaeology reference is made in general to at least three distinct shipbuilding traditions i.e. a Nordic, a Northwest-European and a Mediterranean tradition. This is as it appears not a perfect grouping of shipwrecks. Close examination shows that many shipwrecks often had features from more than one tradition. This may be particularly true in the historic Dutch lowlands infrastructure, which was a crossroad of maritime trade routes in Europe. As it appears the older watership wrecks had a lap-strake hull, and the younger ones a flush hull. The continuity in this one time change in hull construction philosophy is that both followed local shipbuilding traditions. The remaining text in this paragraph will elaborate on this.
One of the oldest wreck revealing relevant data is the ZN44 constructed somewhere around 1500. This watership was built in a hybrid style in the sense that its wreckage material displayed features of the Nordic tradition mixed with features from the Northwest-European tradition. The Nordic tradition (Crumlin-Pedersen 2004) has three key characteristics. First key characteristic is a backbone consisting of a keel, a stem, and a stern. The garboard strakes are rabbetted in the keel, stem and stern post. This was also observed in the lap-strake watership. The remaining strakes are rabbetted in stem and stern post. Second key characteristic is the lap-strake clinkered hull. Last key characteristic is a light framing system in comparison to the other shipbuilding traditions. The strakes give the ship its primary strength. The strength philosophy is therefore shell based, implying a notion of a strong but flexible rounded hull to cope with the Baltic, North sea, and even Atlantic environment. Although not archaeologically proven yet, it is very likely that shipwrights in North-Holland built ships with Nordic features, but in a local style that shares key characteristics with this tradition. In Flevoland seven wrecks have been found dating back to the fifteenth and sixteenth centuries that fit the Nordic profile, all between 17 and 30 metres in length (Overmeer 2008, 41-56). A study model was made of one of those seven wrecks, the sixteenth century freighter OM11, for analysis purposes (Blok 2010). The conclusion was that the watership resembles the OM11 in underwater shape, dimensions and applied construction techniques.
The lap-strake watership also shared features with the Northwest-European tradition. The strength philosophy in this tradition is bottom based (Hocker 2004a, 65-94), the notion being that shipwrights construct a strong flat bottom to cope with the many maritime shallows and flats in the region, while the strength of the sides is of secondary importance. The bottom is always flat, flush planked, and consists of heavy strake planking and floor timbers. The sides however may be lap-strake. Indeed the hull and framing system of the watership was more heavily built than in the Nordic tradition, but the bottom was lap-strake as in the Nordic tradition. Another feature is that the lap-strake watership used twice bent nails, like the cog, as opposed to clinker nails as a means of fixing the overlapping strakes to one another. Also the keel was a plank instead of a beam. Finally the luting technique used in the watership was the same as in the case of the cog. Moss was used as opposed to animal hair which is generally associated with the Nordic tradition. In conclusion the lap-strake waterships, built in North-Holland, shared characteristics of the Nordic tradition mixed with features of the Northwest-European tradition.
The flush hull construction of the younger waterships had the characteristics of the Dutch flush style of shipbuilding. Maarleveld introduced the term Dutch flush in relation to shipbuilding developments in sixteenth century Holland (Maarleveld 1992). He refers to large sea-going vessels and not locally operated ship types like the watership. The Dutch flush technique is perceived to be a variation to the Northwest-European tradition of shipbuilding, meaning that the shipwright had the bottom based philosophy in mind and used clamps in a shell first approach. New is that the Dutch flush ships in general have well integrated flush sides, as opposed to having lap-strake sides. As described in paragraph 4, the VAL7 wreck actually displayed the features indicating that a shell first construction approach was used in a flush built watership (fig. 9). Also the sides were well integrated in the hull.