On its western side, a tide-rip--to which the chart ascribes a strength of 5 knots an hour at times--caught us, and we were in some danger of being carried inshore, but that the breeze was just strong enough to bear the schooner safely past. The tides in the channel set strongly, and are said to attain in parts a velocity of as much as 5 knots at springs. South of Meroë are the islets of Trak and Treis, and from the deck the red sandstone cliffs of the latter could be seen with much distinctness. Little Nicobar, rising 1400 feet, showed broken and hilly, completely covered with dense jungle, and beyond it Great Nicobar loomed faintly above the horizon. During the afternoon, when in the vicinity of Meroë, we were somewhat excited by a glimpse at what was perchance a specimen of the killer whale (_Orca gladiator_). The first hint we obtained of the presence of such an animal, was conveyed by the sight of a long black fin showing above the water immediately in the course of the schooner. As we sailed over the spot where it had been, we perceived, while looking over the side, a stout, rotund body of a deep black colour, marked with large patches of a yellowish hue about the head and the posterior portion of the back. Only a momentary glance was obtained before it faded from sight in deep water, but we judged it to be some 15 feet in length. The dorsal fin distinctly differed in shape from that figured in descriptions of the killer; instead of being more or less triangular, it was sabre-like, long, narrow, and curved.[68] We were all day journeying from Kachal to Little Nicobar, and had to anchor for the night somewhere west of Pulo Milo. As it became dark, immense flocks of pigeons left the forests of Little Nicobar for Trak and Treis, where they roosted for the night, and when day dawned we saw them passing back again. That morning, however, we made sail again, and reached our anchorage in a very short time. The harbour is a fairly good one, and is formed by the coast of the island here bending to form a right angle, and by the island of Milo, which forms a protection on the west. Good shelter is afforded during the south-west monsoon--the most important consideration; and at other times only strong northerly winds need be feared. We found 7 fathoms sand in the centre of the channel where we rounded to; and soon after the sails were down, three wild-looking fellows in black Chinese jackets came alongside, followed presently by a couple of old men clothed in red cotton.