Sunday, June 19, 2011

Seagoing Capabilities of Monohull Dugouts

Landstrom's reconstruction of a
Greek galley of the Homeric era.
Click any image to enlarge.
In a recent post about competing concepts for the reconstruction of Greek galleys of the Homeric era, I suggested that the one championed by Bjorn Landstrom seemed unlikely due to its apparent lack of seaworthiness. My assumption was that the boat – a long, sleek monohull dugout equipped with rowing outriggers, but no outrigger floats – had too little stability and too little freeboard to venture outside of well-protected waters. To counter this argument, reader Edwin Deady, who maintains the website Dark Age Boats, called my attention to the Monoxylon II experiment, which amply demonstrated the seagoing capabilities of an open monohull dugout of an even more ancient design.

Conducted in 1998, the Monoxylon II Expedition sought to determine whether dugouts could have been the vehicle for cultural transmission in southern Europe around 7,000 BC. This was the time at which the Mesolithic began to give way to the Neolithic in Europe, as evidenced by the spread of agriculture, animal husbandry, new pottery styles and other technological advances. There's ample evidence that the beginnings of the new technical complex in Europe were imported from western Asia, not homegrown. And since its initial appearance in Europe was not only along the mainland shores of the Aegean and Mediterranean seas, but also on numerous islands, it must have been transmitted, at least in part, by boat.

Evidence about the nature of those boats appeared in 1994 with the discovery of a large, well-preserved oak dugout in Lake Bracciano, on Italy's west coast. Although discovered in a lake, the boat's size (35 feet LOA; beam of 3.5 feet at the stern and 2.5 feet forward) appear excessive for lake use. It is thought that higher sea levels at the time to which the boat has been radiocarbon dated (5450 BC) would have caused the lake to be connected to the sea by a river, so there is good reason to believe it was a seacraft.

The canoe had four braces, created by leaving original material standing proud on the interior surface, in the manner of ribs. The recovered hull's thickness varied from 2 to 4 cm., but it is thought that the wood may have compressed over the millennia, and that the original thickness may have been about 5 cm. The possibility of the use of sail is suggested by the presence of a rectangular notch in the bottom (a possible mast step?) and some fragments of textile, but the evidence is far from conclusive. Paddles were more likely the primary means of propulsion.

Monoxylon II, with a crew of eleven.

In 1988, Czech archaeologist Radomir Tichy led a team that recreated the Lake Bracciano dugout quite faithfully. The finished replica was some 1.25 meters shorter than the original, not by plan, but because rot was discovered in the trunk partway through construction. This truncation also resulted in the elimination of one of the four "ribs" in the replica. Because the upper edges of the Lake Bracciano boat had been lost and its full height is therefore unknown, the replica's depth, at 90 cm, was a guess. A substantial amount of construction was done with Neolithic-style stone tools to prove the concept, after which iron tools were substituted for efficiency. The experimenters estimated that to build the entire boat using only Neolithic tools would require only 300 man-hours.

That same year, the team campaigned the canoe in various locations around the northern shores of the Mediterranean. Various crews of 8 to 10 paddlers plus a helmsman on a steering oar put about 500 miles under the boat's keel in a variety of conditions. With the boat's center of gravity below the waterline, the crew found stability to be very good, even in 2-meter waves (although bailing was necessary in those conditions). The boat was not noticeably affected by current, but headwinds greatly impeded progress. (They paddled in conditions up to 7-9 Beaufort.) Average speed under all conditions was 4 km/hr. Cargo of more than 100 kg. of obsidian (an early trade good), plus water and bagged wheat did not overload the boat. With a total load of nearly a ton (cargo plus crew), the paddlers felt that much heavier loads would have been both feasible and safe.

Tichy concluded that the dugout was indeed a viable vehicle by which the "Neolithicization" of Europe might have occurred. Some islands in the Mediterranean would have required more than a single day's paddling to reach, but none, apparently, were out of the practical range of a well-built monohull dugout, and "it would be possible to travel the whole coast of the Western Mediterranean up to Sicily in at most several months of persistent going," Tichy wrote.

According to Tichy, "A place probably without preneolithic occupation could be colonised by a group of 40 people with the necessary minimum amount of domesticated animals and crops a total of 15-18 ton load (sic). The load would be carried with 10 to 15 boats, each of them would take one to two tons."

I believe Tichy is here referring to colonization of a carefully planned nature – a conscious intent to establish a permanent community en masse. I think the process could also have occurred on a much smaller scale, with possibly as few as one or two boats containing one or two families and a couple of goats striking out to set up a farmstead on unoccupied land across a strait or down the coast.

Afterword: Once I got going on this post, I realized that monohull dugouts have proven themselves as seagoing vessels in more modern times than the Neolithic, or even the Greek Bronze Age. The Native Americans of the Pacific Northwest famously conducted whaling, warfare, and trade in their huge cedar canoes from Alaska to California well into the 19th century, and from 1901 to 1904, Capt. John Voss took his modified Nootka dugout Tilikum two-thirds of the way around the world. The Maoris also built enormous monohull dugouts into the historic era, and it is thought that these may have been the vehicle by which New Zealand was colonized from Polynesia prior to 1100 AD.

Acknowledgments: Much of this post derives from the English-translation appendix to Monoxylon II by Radomir Tichy (Dobrodruzstvi Experimentalni Archaeologie, 1999). Also consulted was this article in Discover. Many thanks to Edwin Deady for his inspiration and assistance on this post.

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