Cruise of the 'Alert'. R. W. Coppinger

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СКАЧАТЬ evidently out on a foraging tour; he hovered for a while about our mastheads, reconnoitring our decks, and then soared away.

      As we sailed along the east coast of San Antonio (the largest island of the Cape de Verde group), we observed a small outlying island rock, composed of closely packed vertical columnar masses of rock (probably basaltic), which, from their artificial appearance, reminded one forcibly of the Giant's Causeway, or of the Staffa Columns. The hills of the main island, which sloped up majestically from a low rocky beach to peaks five or six thousand feet high, were clothed with herbage, whose varying tints of green, to which the shadows of the secondary peaks added dusky patches of brown, created a most pleasing landscape.

      We reached the harbour of Porto Santo, St. Vincent, on the afternoon of the 23rd of October, and soon after the anchor was dropped, those of us who could leave the ship proceeded to land. As we approached the beach, we were greatly struck by a contrivance, new to most of us, for carrying coals from the yard where it is stowed to the shipping wharves, a distance of nearly a quarter of a mile—a row of posts, like those used for telegraph wires, placed about four yards apart, and supporting on iron rollers a long endless wire, to which are hung at intervals large metal buckets containing the coal. There is an incline from the depôt to the wharf, and consequently, as the full buckets travel down to the lower end of the circuit, and are canted so as to discharge their contents, the empty buckets pass up the incline back to the coal-yard, and so a circuit is completed. Most of the large passenger-steamers traversing the South Atlantic find St. Vincent a convenient place to stop at to replenish their bunkers, and it is to this coal trade that the island owes its importance.

      After a cursory inspection of the little town, which presented a very neat and orderly appearance, we strolled out into the country, following the direction of the western shore of the bay. The country exhibited a tolerably green appearance, and we were informed that vegetation had been exceptionally good during the previous two years, owing to the rainfall having been much above the average. Of trees of course there were none to be seen, and of shrubs only a few stunted representatives, scattered singly or in patches. A species of rank grass, however, flourished, and here and there a rather stately fungus raised its head as if in defiance of its otherwise sterile surroundings, the blown sand of the foreshore supplying sufficient nutriment for its humble wants. Of dead shells a great variety were picked up on the beach between tide marks, including representatives of the genera Arca, Patella, Cardium, Harpa, Littorina, and Strombus; a very perfect Spirula shell was also noticed. The blown-sand ridges above high-water mark were everywhere perforated by the burrows of a very active grey-coloured crab (Remipes scutellatus), whose feet terminated in sharp incurved claws admirably adapted for the creature's mining operations. Its burrows extended obliquely downwards, and to a depth of two feet from the surface of the blown-sand ridges. A couple of grasshoppers were the only other additions made on this occasion to our zoological collection.

      The afternoon of the next day (24th October) I was enabled to devote to dredging operations, working over the bay at depths varying from two to twelve fathoms. From these I obtained some large and active specimens of a large wing-shell, the Strombus pugilis, whose gymnastic performances, when subsequently placed in a vessel of sea-water, excited general interest. Armed with his long powerful foot, he struck out boldly in all directions, the operculated extremity acting like a sword blade, and alarming me for the safety of the seaweeds and other more delicate organisms which occupied the same vessel. When disposed to turn about, it protruded the foot so as to half encircle the shell, and by then rapidly straightening the organ the desired change of position was effected. It was very interesting to see the complete control which the animal thus exercised over its heavy and apparently unwieldy shell. In twelve fathoms of water we came upon a great quantity of blue-spined Echini, the tangles of the dredge in one short haul bringing up about two dozen. Fishing-lines were also brought into requisition, resulting in the capture of some fishes of a pale crimson colour, belonging to the blenny family.

      In the evening of this day (24th October) we sailed from St. Vincent. Up to the 29th instant the north-east trade wind proved fairly propitious, but it now failed us completely; and as we were at this time in latitude 8° N., and there were otherwise unmistakable indications of our having arrived at the "Doldrums" (the region of equatorial calms), steam was had recourse to. Under this artificial stimulus we proceeded at a rate of from five to six knots, a speed unfortunately too great for the use of the tow-net; and on this occasion the circumstance was all the more vexatious, as the surface water seemed peculiarly rich in animal life. Ultimately, however, determining on sacrificing some bunting in the cause of science, I put a tow-net over the stern, and the captain aided me materially by towing from the end of the lower studding-sail boom a ten-foot trawl-net. Between the two we succeeded in capturing some water insects of the genus Halobates, several beautiful large Ianthinæ, but unfortunately with their fragile shells partly broken and severed from their rafts; also a Physalia, a small free-swimming Actinia, some discophorous Medusæ, and several Pteropod Molluscs of the genus Hyalea. For several consecutive days the surface water after dusk was thronged with the above-mentioned Medusæ, whose tough gelatinous discs, of three inches diameter, continually clogged up the meshes of the tow-net. On the 2nd of November we obtained some Globigerina forms, several Crustaceans, some minute Pteropods of the genus Cuvieria, and a host of minute Confervæ, of the kind met with previously to the northward of Madeira. On the afternoon of the 5th of November, when we were about a hundred miles from St. Paul's Rocks, we noticed that the little petrels, which for weeks had accompanied us in great numbers, were now feebly represented, and in the evening were completely gone. Perhaps they had found out their proximity to terra firma, and were gone for a run on shore. It is very strange how these birds, which follow ships over the ocean for thousands of miles, can manage to time their journeys so as to reach land for their breeding season. That the same individuals do follow ships for such great distances we have good evidence; for Captain King, in his voyage of the Adventure and Beagle, mentions a case in which the surgeon of a ship, coming home from Australia, having caught a Cape pigeon (Daption capensis), which had been following the ship, tied a piece of ribbon to it as a mark, and then set it free. The bird, recognized in this way, was observed to follow them for a distance of no less than 5,000 miles.

      From the last date to the 9th of November, but little of interest occurred. One day a petrel (Thalassidroma pelagica) had been caught with a skein of thread; and on opening the body the crop was found to contain a number of stony particles, bits of cinders, minute shells, and otolites of fishes. In the tow-net we caught a number of Rhizopods, of 1⁄20 inch diameter, which kept continually unfolding and shutting up their bodies in telescopic fashion. When quiescent, the animal is egg-shaped, and about the size of a mustard seed; but when elongated, it is twice that length, and exhibits a tubular sort of proboscis armed with an irregular circle of vibrating cilia. We also obtained a Pteropod resembling the Criseis aciculata, an Ianthina, and some hyaline amœbiform bodies, which were entirely beyond my powers of recognition. On the following day we got more of the pretty violet shells (Ianthina fragilis), several Crustaceans, including a large and perfect Glass-crab (Phyllosoma), and several large Salpæ and Medusæ.

      On the 12th of November we entered the north limit of our surveying ground, being in latitude 17° S., and in the vicinity of the Abrolhos Bank. Here, in latitude 17° 18′ S., longitude 35° 34′ W., we made a cast with Bailie's deep-sea sounding apparatus; reaching bottom in 1,975 fathoms, and finding it to consist of "Globigerina mud," of a pasty tenacity, tinged with red, and containing a great mass of Globigerina tests, whole and fragmentary. Later in the day, when in latitude 17° 32′ S., longitude 35° 46′ W., we again sounded, getting bottom in 700 fathoms, and bringing up a sort of light-grey ooze. Towards evening we struck soundings in thirty-five fathoms, over the Hotspur Bank. There we made a successful haul of the dredge, finding the bottom composed of dead coral encrusted with Nullipores, Polyzoa, and slimy Algæ, and containing in its crevices some Crustaceans of the genera Actæa and Corallana, and a few Annelids. The stony masses of coral which we brought up were pierced in all directions by boring molluscs; and one specimen of a long elaborately woven sponge СКАЧАТЬ