Qualifications and Considerations

Page 9 of 10

Figure 15

Recommended Dugout Canoe Design

Diagram showing recommended hull design of a dugout canoe

© 2005 Bill Bevis

  1. The test used excellent paddlers with modern equipment. We all agreed that with river men among them to instruct, such as Clark and Cruzatte, by the time the Corps reached the Yellowstone they were experts. They were also in their twenties; we averaged 50 years old. They were a lot stronger. Their one piece paddles, judged by museum paddles of the day, were probably a lot like Feather Brand cheap paddles today. To a man, our hot shot crew agreed that the Corps could have done anything we did, and more. A draw stroke, a high brace, ruddering—this was not news to voyageurs.
  2. We tested the canoes without several thousand pounds of freight. Yes, but on at least three occasions the 20' and 33' canoes were paddled half-full to full of water. We estimated that the large canoe probably held 50 to 70 cubic feet of water, or about 3,000 to 4,300 pounds (Boss estimates their loads at up to 6,000 pounds). So loaded, the 33-footer had its bow submerged in a whirlpool, turned from upstream to downstream, lumbered down the eddy line turbulence and was paddled to shore by 6 people (another thousand pounds). All agreed that the boat was stable, just low and slow. We think that loads would have made our paddle less fun, but if the job was just to reach the other shore safely, we all felt that 6,000 pounds of freight would make no essential difference in the boat's handling capacity.
  3. One of the most frequent problems mentioned in the journals was wind and waves forcing them ashore. After having no problems paddling swamped canoes, we wondered if the waves threatened to wet the cargo, rather than put the canoe in jeopardy.
  4. We had a lot of paddlers. Not after the first trials proved the boats so stable. Often two or three took the 18' and the 20' boats, and the 33' boat was paddled in very heavy water by four. Certainly two or three people could have handled it gently and slowly.

Preliminary Conclusions

  1. The boats behaved in essentially similar ways, differing in degrees. It seems that weight and overall width of bottom are distinguishing hull characteristics. The straight sides, or the chines, made little difference. We were surprised, almost shocked at this development, and I hope to talk more to canoe historians and hull designers about the characteristics of heavy, "battleship" hulls versus modern canoes.
  2. Since the Lewis and Clark canoes were built to carry loads, it is very possible that the lighter Marten 18' design (800 pounds) would have been more of a ballast battleship when loaded, and of course the lighter boat carries more weight. But they said "stout canoes," and they certainly regretted the time spent making more, so possibly they feared breakage and cut them thick. We cannot rule out any particular hull: we paddled one of the lightest, and one of the heaviest canoes that we could find anywhere. We paddled them both empty and full of water, and found them riverworthy in all conditions.
  3. We found no reason to think that the Lewis and Clark ascent of western waters was limited by the dugouts' performance in the river.
  4. We agreed, as canoeists, that while the widest bottom in the middle was paramount, a slightly rounded edge, and an efficient, narrow but rounded entry line at the bow, was preferable for both cordelling and paddling. These boats had stability to spare, and river users in 1800 were very accustomed to small boats. There's no reason those paddlers would not have sacrificed a bit of stability to more efficiency while dragging a hull upstream. This is not the situation with the reenactment groups, who need a stable boat full of less experienced paddlers for short distances.
  5. The rule of thumb on the Missouri was a wide flat bottom for the sandbars. But the Mandan canoes were built for an ascent in high water, and one would think that hull efficiency might easily have equaled shallow draft as a consideration.

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