An ultrasonic‐measurement technique and data‐processing scheme are described in which time intervals are measured between transducer resonance oscillations within the structure of successive unrectified echos rather than between echo leading edges. When plotted against the transducer resonance period, these time intervals determine a family of straight lines that have a single point in common at zero transducer resonance period. It is propo‐ed that the transit time associated with this common point is the true travel time for sound in the medium unperturbed by transducer effects.