
\section{Surface tension measurements}	
	\begin{figure}[h!]
		\centering
		\includegraphics[width=0.65\linewidth]{SurfTens_SDS_final.eps}

\caption{Surface tension versus sodium dodecyl sulfate (SDS)
  concentration at the air/aqueous solution interface
  (closed symbols), diethylphthalate (DEP) and DEP-saturated aqueous
  solution interface (closed symbols), and silicone oil ($350cst.$)/ aqueous
  solution interface (blue squares). Although the surface tension is
  lower for the silicone oil than the air interface, the interfacial
  tension gradient does not change significantly. We therefore assume that the transient
  DEP/pure aqueous solution interface at the front of the droplet exhibits a
  similar gradient of $0.01$N/m/M stated in the manuscript, which is
  the dominant driving force for the droplets. As a
  function of [NaCl], fits to the von Szyszkowski equation (dashed
  lines) reveal that the surface tension gradient is independent of salt
  concentration for a given interface. On the other hand, the CMC (intersection with the
  horizontal line) decreases with salt for both the aqueous and
  the DEP-saturated interface, but the difference $\Delta$CMC is
  progressively smaller. We thus use these estimates of  $\Delta$CMC to fit
the velocity decrease with [NaCl] in Fig. 3 in the manuscript.}
		\label{fig:surftenssdsfinal}
	\end{figure}

\end{document}
