Page 12 - Nicolaes Witsen & Shipbuilding in the Dutch Golden Age

Foreword
shell described by Witsen was held tog ether by cleats, and frame timbers were sub sequently fitted into the shell. According to the method of construction described by Van Yk, which strikes us as much more modern, the planking was fastened to the pre-erected frames.
After Hornell called attention to thi s fundamental dif- ference in the methods of shipbuilding in 1 948,1 it has become a subject of study the world o ver.2 The older system is now known as “shell first,” whereas Van Yk de- scribes a system that is characterized as “skeleton first” or “frame first.” Since Hornell’s days it has become clear that, in practice, the difference is often not absolute—i.e., intermediate forms are commonly encountered. Neverthe- less, the distinction is most useful in analyzing modes of shipbuilding.
It is worthwhile to c onsider briefly the hi story of this unfamiliar shell-first method of construction. The northern European variation on the method was the clinker system, which results in str akes partly overlapping each other, much as roof tiles do. Between the overlapping parts some sort of luting was often applied, suc h as tar-drenched moss, after which the strakes were fastened to each other by means of rivets. The natural result of this manner of shipbuilding is a coherent shell into which the floors and futtocks were subsequently fitted. In an older variation on the system the strakes were not riveted to each other but sewn, commonly with rope made from bark. The earliest evidence for thi s system is furnished by the Hj ortspring boat, which dates from 340 bc and was fou nd in 1921 on the Danish island of Als.3 Early in the twentieth c entury this method of joinery was still employed in the construc- tion of Skolt Lapp boats, used in Scandinavia north of the Polar Circle. The oldest known riveted clinker planking is that found in the Nydam boat. 4 It dates from the four th century ad and is now permanently on exhibition in Got - torp castle in Schleswig, Germany.
A much older system of joinery was used in the Medi-
terranean. It is characterized by tenons set into mor tises in the thickness of the strakes, which the tenons join sol- idly together because dowels traverse both pl anks and tenons and thus secure them. The excellent quality of these joints rendered c aulking superfluous. The earliest shipwreck in whic h we enc ounter this pegged mortise- and-tenon system dates from c. 1300 bc.5 Given this early date, it is not surprising that a pa ssage in the Odyssey, the historic context of which must be dated to the eighth century bc, turns out to be a description of this mode of construction.6 Odysseus builds the ship on whic h he will depart from the i sle of the nymph C alypso. The method was later taken over by the Romans, a landlocked people who took to the sea because there was no other option. They attributed the original invention of the method to the Carthaginians, as may be deduc ed from C ato’s descrip- tion of the c onstruction of the lid of an olive pres s, the orbis olearium, which made use of these joints; he called them coagmenta Punicana or Punic joints.7 This appella- tion is correct, for we may regard the Carthaginians as de- scendants of the Phoenicians.
As it happens, one of the earliest discoveries of Punic joints was made in the Netherlands in 1892. 8 Excavation at the site of the Roman fort Fectio (Vechten) near Utrecht revealed the wreck of a river barg e at a depth of six me- ters. Unfortunately, it was not possi ble to raise and c on- serve the vessel at the time, but it could be established unequivocally that the j oinery of the pl anking was made according to thi s method. This woodworking technique was seemingly forgotten after the retrea t of the Roman armies from western Europe.
A factor that contributed to the abandonment of Punic joinery was the metamorphosis that took place in its ap- plication in Mediterr anean shipbuilding after the sec ond century ad. The distance between the tenon s connect- ing adjoining planks gradually increased until finally the system of carvel planking evolved, in whic h the str akes
x
Lid of an olive press, after Cato’s description in De agricultura. (Drawing by André Wegener Sleeswyk)