  This fluid dynamics video shows drops of water being transported by a mean
flow of oil, in a microchannel shaped as a logarithmic spiral. The channel
shape means that the drops are submitted to an increasing shear and elongation
as they flow nearer to the center of the spiral. A critical point is reached at
which a long singular tail is observed behind the drops, indicating that the
drops are accelerating. This is called "Tip streaming".
