The empirical quantity defined by \[i=\frac{i_{\text{d},l}}{c_{\text{B}}\ m^{\frac{2}{3}}\ t_{1}^{\frac{1}{6}}}\] the equation where \(i_{\text{d},l}\) = @L03534@, \(c_{\text{B}}\) = bulk concentration of the substance B whose @R05222@ or @O04362@ is responsible for the wave in question, \(m\) = average rate of (mass) flow of mercury (or other liquid metal) and \(t_{1}\) = drop time.