Big whirls have little whirls
Which feed on their velocity.
And little whirls have lesser whirls,
And so on 'til viscosity.
- Richardson, L. F. Weather Prediction by Numerical Process (Cambridge Univ. Press, 1922).
I was introduced to this delightful rhyme during a seminar given by an engineer-turned-microbiologist. He had totally awesome and interesting things to say about swimming marine microbes that I will have to remember to blog about later.