Episode 10: What happens to a drop of liquid that meets the surface of another liquid? Researchers in Toulouse conducted an experiment to answer that question. They added a drop of dichloromethane to water, after having put a refractant into both liquids to lower their surface tension. Then they observed the behaviour of the drop: the dichloromethane spread upon the water and started to evaporate, hence lowering its temperature and surface tension, which caused it to throb repeatedly. The result of this experiment could have therapeutic applications, for example by dispensing drugs more efficiently on diseased tissues.