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This paper reports measurements of the shift with hydrostatic pressure and uniaxial stress of the temperature for a metal-to-semiconductor transition in ${\mathrm{V}}_{2}$${\mathrm{O}}_{3}$; of the change with pressure and uniaxial stress of the resistivity in the metallic phase and the activation energy for condution in the semiconducting phase; and of the optical transmissivity in both phases. The results are first interpreted on the basis of a model involving a crystalline distortion to lower symmetry in the semiconducting phase, and the behavior of transition temperature and conduction under applied stress is shown to fit this microscopic model satisfactorily. The changes in transition temperature and energy gap with stress are also analyzed, starting from the statistical model of an energy gap which is linearly dependent on the number of activated carriers; the data are found to fit this model very well.