... that the ship was being 'attacked' on all sides from different directions by pulsing light-bands. A dull 'strobe-light' effect flashed through a mist, giving the bands a dirty white to gray colouration which was not a 'smooth' colour, but rather grainy in appearance. The bands were about 2 m wide and about 2 m apart and moving at speed. At first it was difficult to discern whether or not the bands were in the water or just above the surface, as no form of reflection or distortion was visible off the hull. In the end, I decided that the effect must be waterbourne if only because nothing was visible in the vessel's wake. "The most intense activity was observed on the starboard side of the ship where the phenomenon appeared to stretch as far as the horizon. At this stage, it did not appear localized, just a mass of high-speed interacting bands of light. The effect is shown in the first sketch. As is usual on an 'all aft' ship, you become 'deaf' to the constant background noises, but I gradually became aware that the pulses of light seemed to match those of the main engine's throb, that is, about two per second. The radar (3 -cm radar, running on the 24 n. mile range), and the echo-sounder (indicating a water-depth of about 35 fathoms), were switched off in turn to see if any change was discernible, but there was not. "However, at ...