Marangoni (1878), provided a wealth of detailed information on the effects of variations of the potential energy of liquid surfaces and, in particular, flow arising from variations in temperature and surfactant composition. One aspect of this science is seen today to bear on important phenomena associated with the processing of modern materials. The role of the basic effect in technology was probably first demonstrated by chemical engineers in the field of liquid-liquid extraction. Indeed, phenomena attributable to Marangoni flows have been reported in innumerable instances relevant to modern...