High-frequency (> 1 cpd) variations in travel time of acoustic transmissions over ocean mesoscale distances are known to be dominated by the effects of internal-wave displacements of the sound-speed stratification (Flatt¿ et al., 1979; Flatt¿, 1983a). Variations in the difference in travel time between transmissions in opposite directions along the same path (reciprocal transmissions) are dominated by internal-wave currents . We investigate the usefulness of a two-mooring acoustic system for determining the statistical variances of internal-wave displacements and currents as a function of depth, geographical position, and time. We find that statistical fluctuations in the internal-wave field itself prevent recovery of range-dependent information between the two moorings. However, range-averaged information can be obtained about mean energy level and about vertical energy migration. We find that uncertainties in the buoyancy and sound-speed profiles do not significantly affect the usefulness of the method.