Batavia tree-ring study reveals Dutch ship ingenuity
EARLY 17th century Dutch ship builders used multi-layered hulls sourced from the best timbers in Europe to ensure they survived the rigours of ocean travel.
Their ingenuity and ability to adapt to changing economic conditions is confirmed in a new paper titled ‘Batavia shipwreck timbers reveal a key to Dutch success in 17th-century world trade’ (https://bit.ly/3bxBuBn).
Batavia was built in Amsterdam in 1628 by the Dutch East India Company, or Verenigde Oostindische Compagnie (VOC), featured in the latest issue StreetWise at www.streetwisemedia.com.au.
On June 4, 1629, the ship wrecked on its maiden voyage when it struck Morning Reef in the Houtman Abrolhos islands off Geraldton.
The wreck was discovered in 1963 and its timber remains are on display at the WA Shipwrecks Museum in Fremantle.
According to researchers Aoife Daly, Marta Dominguez-Delmas and Wendy van Duivenvoorde, oak was the preferred material for shipbuilding in northern and western Europe. Maritime nations struggled to ensure sufficient supplies to sustain their ever-growing mercantile fleets and networks. Their results demonstrate the VOC successfully coped with timber shortages in the early 17C through diversification of timber sources (mainly Baltic region, Lubeck hinterland in northern Germany and Lower Saxony in northwest Germany); allocation of sourcing regions to specific timber products (hull planks from the Baltic and Lubeck, framing elements from Lower Saxony); and skillful woodworking craftmanship (sapwood was removed from all timber elements).
“These strategies, combined with an innovative hull design and the use of wind-powered sawmills, allowed the Dutch to produce unprecedented numbers of ocean-going ships for long-distance voyaging and inter-regional trade in Asia, proving key to their success in 17th-century world trade.”
By the early 17C, wood had become one of the top five imports in the Dutch Republic, together with grain, salt, herring and textiles. Unfortunately, records of timber procurement are scant and what archives exist are difficult to translate and interpret.
“Fortunately, material evidence from those flourishing times can be found on VOC shipwrecks around the world,” the researchers said, adding analysis of timbers provides direct evidence of craftmanship and woodworking techniques, timber procurement areas, and trade connections in specific historical periods – “bridging the gap between the historical and archaeological records”.
Batavia
FROM the time it sailed from Texel in 1628 as the flagship in a fleet of six VOC ships bound for Batavia (modern-day Jakarta) until its sinking off WA the following year, Batavia never underwent repairs or refitting, so all of its timbers belong to the ship’s original construction.
“Batavia’s remains provide a unique opportunity and an exceptional resource to study state-of-the-art 17th-century shipbuilding,” the researchers said.
Batavia measured 160 Amsterdam feet (45.30m) in length over its upper deck, 10.19m in beam, and the height between the top of its keel and lower deck was 3.94m. It was constructed using a bottom-based method that applied two thick layers of oak hull planking below the ship’s waterline.
Researchers collected 137 samples from 101 timbers between 2007 and 2017 and analysed them using dendrochronology, tree ring dating.
They said archaeological studies of Batavia hull remains in the early 2010s corroborated historical documents that VOC shipwrights prioritised in their construction a strong and watertight hull, well protected from Teredo molluscs (shipworms) and other marine organisms.
“They accomplished this by reinforcing the construction in the lower hull with multiple layers of timber elements. Two layers of external oak planking provided the bulk of the hull’s strength, which the builders further reinforced and protected with an outer layer of pine sheathing.
“They sandwiched the frames between these outer layers and a layer of oak ceiling planking on the interior, which was further strengthened and protected below the lower deck with a pine floor. The shipwrights enhanced the hull’s watertightness by slightly offsetting the seams of the two layers of oak hull planking, reminiscent of the way overlapping roof shingles are laid.”
This construction method also found on other VOC ships with multiple timber layers, “produced an extraordinarily thick hull, which created a laminate-type layering of timbers in the lower hull; the combined thickness of Batavia’s two layers of hull planking alone was 18cm”.
Researchers found the combined thickness of Batavia’s outer hull planking was more than twice that of contemporary French, English, and Dutch single-planked vessels.
The paper is published by PLOS One, a peer-reviewed scientific journal published by the Public Library of Science (PLOS) since 2006.
Featured image: Patrick Baker
