Familiar to pastry cooks, the “layer upon layer upon layer” technique – this time in oak – took Dutch wooden sailing ships around the world in the 17th century.
Flinders maritime archaeologist Dr Wendy Van Duivenvoorde has published a new book that describes the shipbuilding techniques that helped the mercantile fleets of Holland dominate the global trade in spice, the most valuable commodity of the age.
Dr Van Duivenvoorde says that the most valuable clues to the shipbuilding secrets of the Dutch haven’t come from the historical record, but from a remnant chunk of one of Australia’s most famous shipwrecks, Batavia.
Batavia sank on June 4, 1629 on Morning Reef off the coast of Western Australia, eight months into its maiden voyage to the Dutch East Indies (modern Indonesia).
Dr Van Duivenvoorde documented and analysed the only substantial remaining portion of the ship, a section of its larboard counter and hull side, which was the subject of a major conservation project by the Western Australian Museum. It is now on display in Fremantle.
The fragment comprises only some four per cent of the original ship, but still provides unique insights into the shipbuilding technique known as double-planking used by the Dutch East India Company (VOC) from around 1590 up until around 1650.
Dr Van Duivenvoorde said unlike the later standard approach which employed frames, the VOC ships were built using the age-old “bottom-up” technique, meticulously placing long beams and planks that had been shaped with heat to form the structure of the ship.
Batavia and its fellows were given extra strength by the addition of a second layer of planking, which in turn was covered by a sheathing of pine. Copper sheeting was also incorporated at the rear of the boat and the outer layers of wood were coated with a mixture of tar and goat hair.
In addition to adding strength, Dr Van Duivenvoorde said the double planking contributed to waterproofing and also helped the timbers to resist the ravages of the boring teredo worms of the tropics.
Keeping the cargo dry was crucial, not only to protect the valuable cargo, but for safety reasons: heat from rotting spice or grain could, and did, result in shipboard fires.
The double-planking technique died out some time after mid-century, probably for a number of reasons.
“It must have been very time-consuming and expensive, and also would contributed to deforestation,” Dr Duivenvoorde.
The hull planks of the Batavia have been matched to slow-growing, straight-trunked oak forests in Poland, which were also the source of wooden panels used by the Dutch and Flemish old masters.
“After 1643, you don’t see a single piece of that oak in Europe, so these forests may have been completely denuded, and this way of building was just not sustainable,” Dr Duivenvoorde said.
Dutch East India Company Shipbuilding – The Archaeological Study of Bataviaand Other Seventeenth-Century VOC Ships is published by Texas A & M University Press.