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    Ships as dancers
    From: John Huth
    Date: 2010 Feb 23, 18:47 -0500

    Here's a general question.   I've been looking at some of the factors affecting the stability of Viking sailing vessels - specifically knarrs versus longboats.   One issue seems to be the moments of inertia and how they couple to each other in the presence of waves.

    Since there are a bunch of physicists on this site, you might be familiar with the "tennis racket theorem", which says that rotational motion about the largest and smallest moments of inertia are stable, while the rotation about the intermediate moment of inertia is unstable.   I've always been fascinated how in my kayak, a bit of yaw when surfing a wave very rapidly gets converted into a roll.   But, I digress.

    I was watching the some of the free-form ski competition in the Olympics and marveled at how the jumpers could convert one kind of rotation into another through twisting motions and the use of arms.   

    That got me to wondering - in literature (read: fiction, or perhaps some reports from history), are there any memorable quotes comparing ships to dancers?

    Or perhaps one vessel to a dancer and another to an ox?   Or...well, you get the idea.

    Thanks in advance!

    John Huth
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