RoDaSm

They used to sit on top of counters in stores, and they were normally filled with orange juice, and a stirring arm rotated very slowly. I believe that the motion of the liquid created some kind of cooling effect. Can anyone confirm this and explain how? And what were they called?

Lie on the ground on a hot day and the legs of cattle in the distance seem to shimmer. In fact most things close to the ground in the distance seem to shimmer. Could someone explain to me what this is and what it is caused by? It is a form of refraction but there is a special name for it.