Re: [baidarka] kostochki

wayne steffens (
Fri, 15 May 1998 13:00:07 -0500

Message-Id: <>
Date: Fri, 15 May 1998 13:00:07 -0500
From: wayne steffens <>
Subject: Re: [baidarka] kostochki
In-Reply-To: <>

At 12:51 PM 5/15/98 EDT, you wrote:

>Also, I came across a 1993 Scientific American video which shows a
>computer model of a baidarka, used to illustrate the frame flex and the
>use of ivory inlays between the forward deck stringer and deck beams(and
>maybe other parts?) to facilitate this flexure. I found no mention of
>these in Brinck's book and was wondering how necessary they are or if
>they simply reduce some of the wear.

Ahh, a fellow kostochki enthusiast. Here are some comments to my questions
on the matter some time ago:

wayne steffens wrote:
> Does anyone out there in baidarkaland have any comments on kostochki, the
> bone/ivory joints used in some older (pre 1800 I guess) Aleut kayaks?
> Has anyone tried to use them, or a modern interpretation of them?
> What do the kayak designers among you think about the
> principle/functionality of these joints? Could they significantly improve
> skinboat performance? How? It seems that the Aleuts would have to spend a
> considerable amount of time fashioning these joints so (I am assuming) they
> were quite functional. Then again, they did stop using them...

John Winters replied:

There is a theory that the flexible framework might improve performance
but I know of no solid proof of that nor do I fully understand the
theory as it applies to kayaks. from my reading I get the impression
that the bone served as a wear strip at the joints. It certainly must
have been good for that.

I don't know that one can make much of the cessation of the practice
beyond attributing it to changes in attitudes toward the boats. I
believe George Dyson looked into this (and has written about it) He
would be your best source of information.

Greg wrote:

> Hi all,
> I am new to the group, but I was able to read Lubischer's paper on
kostochki a
> while back. After wondering about them for a while I have come up with a
> possible explanation.
> Given that:
> The baidarka is a flexible vessel
> One of the baidarka's main purposes was hunting sea-mammals
> The flexing of the wooden hull pieces could cause the frame to squeak as
> pieces rubbed together.
> Wouldn't it be possible that the kostochki were added to reduce friction in
> order to eliminate noise rather than to increase speed in some way?
> stealth would have been of prime concern to a hunter, and the kostochki
> have served to aid in this regard without reducing the ability of the
frame to
> flex. As I'm fresh out of polished ivory I am unable to test this
> Can anyone else give it a try?
> - Greg

To which Wolfgang replied:

Of all the wood frame kayaks I have built and those of others that I
have paddled, I have encountered only one that squeaked, creaked or
otherwise made any noise, and it was not a baidarka. This boat was
a Greenland boat and I had moved the position of the cockpit and added
another deck beam right next to an existing deck beam and when the
boat twisted, the two beams would rub and make noise.

However, when constructed in the normal way, wood frame kayaks do not
moan, groan, whine, creak, growl or otherwise make noises unbefitting
a hunting animal.

And Paul MacIntyre added:

Last year, somebody I don't recall who, posted that they had used
Dupont - Corian as the kostochki.

And Joe Lubischer adds:

I see that Wayne Steffens' query on the Aleut kostochki generated a bit of
interest. For the record, we know of two craft constructed with the ivory
joints. One is a double, in pieces, at the Burke Museum in Seattle and
dates to c.1900. The Baidarka Historical Society should still have the
original report available and it was also reprinted in the
Contributions... volume. The second example is a single of exquisite
workmanship and 1820 vintage that is held by the National Museum of
Finland and was exhibited in 1993 in Seattle. A circumferential tear in
the skin allowed us to see a small glimmer of white at the keelson joint
and brought us back to X-ray the kayak. A paper on the results is my
winter project.

The Burke Museum kayak used both flat plates and elongated ball and
sockets. The NMF kayak used only flat plates of ivory, but also
incorporated a long baleen strip along the keelson. Both boats were taken
from the Unalaska area.

The $64,000 question is: Why did the Aleut builders go to the considerable
trouble to articulate a design that is inherently flexible due to the
small size of its structural members? (See also George Dyson's
paper on kayak performance.) Suggestions have included speed,
performance, durability in stormy weather, longevity, noise, concern with
the control of power or energy, and cultural borrowing.

Longevity and noise are probably the easiest to rule out. I haven't seen
any significant wear on either old or new kayaks, and failure seems more
often due to breakage--itself not a big problem when the skin is renewed
frequently. To Wolfagang Brink's comment that wooden kayaks don't creak,
we could add the negative evidence of no comments of creaking problems in
traditional kayaks and the copious use of slippery seal oil. Performance,
speed, and power were all important to the Aleut builders and seem
to be the most likely areas for discovering the Aleut motivation.