Slow perturbations of the drop speed of a nearly freely falling, winged, microstructure probe in the upper 200 m at station P are interpreted as vertical velocity fluctuations of an internal wave field. The frequencies of these fluctuations lie in the 2.5- to 4-cph band, near the buoyancy-frequency cutoff. A typical rms value 1.3 cm/s. Indications of the vertical structure of the wave field and the partition of energy among modes are obtained by statistical comparison with discrete mode solutions of the internal wave equation. It is found that the first and second modes carry most of the internal wave energy and that the partition of energy between them may change in 3 days.