The possibility that the ${\rho }^{\prime }\mathrm{}\left(1600\right)\mathrm{}$ is not a true resonance is examined. In the model considered the reactions $\gamma p\to \rho {\pi }^{+}{\pi }^{-}p$ and $e^{+}{e}^{-}\to \rho {\pi }^{+}{\pi }^{-}$ proceed through the production of a virtual $\rho$ meson. The threshold factors associated with the opening of the $\rho \pi \pi$ channel are shown to combine with the virtual-$\rho$ propagators to produce peaks in the $\rho {\pi }^{+}{\pi }^{-}$ mass spectra, similar in mass and width to the experimental spectra. However, a comparison of the relative magnitudes of the two reactions, when combined with experimental limits on the reaction ${\pi }^{+}p\to {\Delta }^{++}\rho {\pi }^{+}{\pi }^{-}$, rules out this mechanism. The roles of final-state interactions and of the virtual-mass dependence of the $\gamma p\to \rho p$ production amplitude are considered. It is then assumed that the ${\rho }^{\prime }$ is a real resonance. The ${\rho }^{\prime }-\gamma$ coupling and the ${\rho }^{\prime }p$ total cross section are extracted. We find $\frac{f_{{\rho }^{\prime }}^{}{}_{}{}^2}{4\pi }=21\mathrm{}\pm 10$ and ${\sigma }_{{\rho }^{\prime }p}=23\mathrm{}\pm 4$ mb, as compared with the $\rho$-meson values of 2.1 ± 0.5 and 22.2 ± 2.6 mb. The background due to a $\rho$ tail in the production of the recently reported ${\rho }^{\prime }\mathrm{}\left(1250\right)\mathrm{}$ is briefly discussed.

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