> The point that I was trying to make is that a very stiff kayak could
> "definitely" be built out of the raw materials available to the
> Aleuts, as demonstrated by the stiffness of the Greenland designs. In
> other words the Aleuts could have built much stiffer boats by changing
> their construction methods, but for whatever reasons did not do so.

If two hulls are identical in design wouldn't the stiffer one be inherantly faster? A flexible hull would form to the shape of the waves and slow the progress of the kayak, would it not?

I think that perhaps the ivory was an answer to a different problem. Perhaps the long trips that the Aleuts were known for, caused the wear, resulting from the flexing of the kayak, to become a problem. Maybe the ivory was simply a way to prevent having to attempt repairs while out on a long voyage.

Ian