Growth of Breath Figures on Fluid Surfaces

Breath figures are the patterns formed when droplets condense on surfaces. We describe studies of such patterns that result when water condenses on the surface of a viscous oil. The average droplete diameter ⟨D⟩ exhibits two regimes of power law growth; at early times ⟨D⟩ ∼ t0.3 and at late times ⟨D⟩ ∼ t. The crossover can be understood as a transition from single-droplet growth to growth dominated by coalescence. A comparison with corresponding growth on solid substrates is performed.