The purpose of this paper is to examine not only qualitatively but also quantitatively the influence of a rise time of longitudinal impact on the propagation of elastic waves in a bar. The adequacy of application of the Love theory for the propagation of longitudinal elastic waves to this problem is discussed by means of the simultanuous measuring of both axial and radial strain waves at the same stations along a bar. Theoretical results based on the Love theory predicts that, as the rise time of impact velocity increases, the effect of lateral inertia on longitudinal waves decreases and rise time of impact velocity increases, the effect o f lateral inertia on longitudinal waved decreases and then the oscillatory wakes of it become negligibly small. Experimental results for a steel bar agreed well with the theoretical results. Moreover, as an example of application, the consideration of the experimental measurement of the dynamic yield stress by using the one dimentional stress bar was made.