Have you noticed in winter, when the van is somewhat warm, when you turn a
corner or brake hard you can feel a slosh of cold air on the back of your
neck? I imagine that behind me, there is a layer of warm air sitting on
top of a bigger layer of cold air, and when the van changes direction, the
big base layer of cold air slops around abit.

Not an earthshaking observation, but one that reminds you how much air
behaves like a liquid.

Alistair, recently fascinated by fluid dynamics after Rain-Xing his
windshield and watching those mercury-like blobs of water scoot across, Bell