The oscillator strength of the (6s6p${)\mathrm{}}^{3}$${P}_{1}$-(6s7s${)\mathrm{}}^{1}$${S}_{0}$ transition and the lifetime of the (6s7s${)\mathrm{}}^{1}$${S}_{0}$ state in $^{174}\mathrm{Yb}$ have been measured to be (8.0\ifmmode\pm\else\textpm\fi{}1.6)\ifmmode\times\else\texttimes\fi{}${10}^{\mathrm{\ensuremath{-}}4}$ and 45.8\ifmmode\pm\else\textpm\fi{}1.0 nsec, respectively. The former value was obtained by use of coherent optical techniques (optical nutation and ac Stark splitting), while the latter was obtained by monitoring cascade fluorescence following pulsed excitation.