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

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СКАЧАТЬ fathoms in the same bay, our work was more satisfactory; but besides some Crustaceans, an Ophiocoma, and an Asterias of a brilliant orange colour, obtained few specimens of any interest. On another day we tried the coast to the westward of Funchal; and as we moved along in the steam-cutter, obtained, by means of the tow-net, several specimens of gulfweed entangling small sponges. The dredge, being put over in seven fathoms, procured for us many specimens of a Cidaris, studded with black spines three to four inches long, and whose oblate spheroidal tests of about two inches diameter were of a beautiful smalt colour. Off the same coast, in forty fathoms, the bottom was found to consist of black basaltic sand crowded with tooth-shells. This fine black sand seemed to form the sea-bottom along the south coast of the island as far out as the fifty fathom line, and from our experience does not prove a favourable berth for our friends the Mollusca and Annulosa.

      Among the Crustaceans obtained in the above dredgings was a species of Glaucothöe new to science, which has since been described by Mr. E. J. Miers, of the British Museum, under the title of "Glaucothöe rostrata."

      On the afternoon of the 12th of October, in company with Sir George Nares, and under the guidance of Dr. Grabham, a British doctor for many years resident in Madeira, we had an opportunity of inspecting a "pinery," established within the last two years by a Mr. Holloway, and by which he expects to amass a considerable fortune. This establishment, which lies to the north-east of the town, at an altitude of about three hundred feet, consists of a series of long, low hothouses with sloping glass roofs, painted white, and facing to the southward, and is heated entirely by the sun's rays. The material in which the pines are planted consists of the branches of the blackberry plant chopped to fragments, and spread out in a thick layer, and in this substitute for mould the young pines are placed, at intervals of about eighteen inches apart. They grow to an enormous size, as we ourselves witnessed; and being cut when they show the least sign of ripening, and packed carefully in well-ventilated boxes, are shipped to London, where they fetch prices varying from twenty-five to thirty shillings each.

      Dr. Grabham was kind enough to give us much interesting information concerning the natural history of the island, which, from his long experience and constant observation, was most valuable. He pointed out to us a considerable tract of land in the vicinity of the town which used to be thickly planted with vines, but which is now only devoted to the cultivation of sweet potatoes. During the last seven years the vine crops have been steadily decreasing, owing to the ravages of the Phylloxera vastatrix, and wine-making is now at a low ebb. The number of trees in the island was also rapidly diminishing, owing to the demand for fuel; and although efforts are made, by the cultivation of pine forests, to supply that want, the demand yet exceeds the supply. In a few years Madeira will no longer be, as its name implies, a land of wood. Although so late in the season, numbers of flowers were still in full bloom; the Bougainvillea with its dark-red bracts, and the yellow jasmine adorning the trellis-work; further up the hill the belladonna lily attracted attention, and on the heights were the old familiar furze blossoms, reminding us of the land we had left behind us.

      On October 12th we weighed anchor, and proceeded to the southward. All that night and the following day we steamed quietly along in smooth water, with a long, shallow ground swell (of which, however, the old craft took advantage to display her extraordinary rolling powers), and late in the afternoon, just before dark, caught sight of Palmas, one of the Canary Islands, whose peak, 7,000 feet high, loomed conspicuously through a light bank of clouds. It was distant seventy miles. On the morning of the 15th we experienced for the first time the influence of the north-east trade wind, which wafted us along pleasantly at the rate of about seven knots. Up to this the only sign of animal life had been a solitary storm petrel, but on the following day a shoal of flying fish (Exocetus volitans) appeared, to pay their respects and greet us on our approach to the tropical zone. During the night, the wind, which had hitherto only behaved tolerably, fell light; and as the morning of the 17th dawned, we found ourselves flapping about in almost a complete calm. There were several merchant vessels in sight, with one of which, a fine-looking full-rigged clipper ship, we communicated by signal, when the usual dumb interchange of civilities took place; she informing us that she was the Baron Collinson, seventeen days out from Liverpool, and we in return giving the latest news we were aware of, viz., the failure of the Glasgow Bank. During the afternoon, a shark, which seemed to be the Squalus glaucus, hovered about our stern. It was accompanied by at least four "pilots" (Naucrates ductor), whose conspicuous dark-blue body stripes showed out in striking contrast to the sombre hues of the shark, whose body formed the background.

      It is during those tropical calms, usually so wearisome to the seaman, that the lover of natural history reaps his richest harvest. On the present occasion the tow-net brought up quantities of a minute conferva consisting of little bundles of delicate straw-coloured fibres, about one-eighth of an inch in length, and resembling, on a small scale, the familiar bundles of "faggots" as one sees them hawked in the streets. Under a high magnifying power the individual fibres composing these bundles were seen to consist of jointed segments marked with dots and transverse striæ as a diatom. When placed in spirit, they at once broke up into a shapeless fluffy mass. The surface water was thickly impregnated with them, yet not so as to impart any obvious discolouration. About dusk the trade wind suddenly returned, and a heavy shower of rain brought to a close a day of great interest.

      On the 18th of October, many of us fore and aft were diligently expending our ingenuity in fishing for bonitoes, of which several (apparently the Thinnus pelamis) were to be seen about the ship; but, to our great chagrin, only one, a small specimen, was captured. The tow-net still brought up quantities of the conferva before mentioned, and multitudes of minute unattached specimens of the Spirorbis nummulites.

      On the following day, as we lay all but becalmed, the storm petrels (Thalassidroma pelagica) appeared in great numbers, settling on the water close to our stern, in flocks of twelve or fourteen, and feeding greedily on the rubbish thrown overboard. It seems that the natural food of these birds (which probably consists of the minute surface organisms) is not within their reach when the surface of the water is unbroken, and hence during calms they are more than commonly anxious to avail themselves of any offal thrown overboard. It was most interesting to observe the neat and graceful way in which they plant their webbed feet on the water, as with outstretched wings and legs erect they maintain a stationary attitude while pecking at the object of their fancy. They appeared to scrupulously avoid wetting the tarsi, and still to use the feet as a means of maintaining a fixed position on the surface of the water. I had never previously observed those untiring little navigators at rest in mid-ocean, but on this occasion we all saw them, with wings closed, floating as placidly on the water as ducks in a millpond. The old idea of their following ships only before and during stormy weather is, I believe, now quite exploded. I think that within the tropics, at all events, they are most numerous in the vicinity of ships during calm weather. Finding animal life scarce at the surface, I tried the tow-net sunk to a depth of about three fathoms, and having previously raked the surface, was enabled to institute a comparison; the result being that similar species were captured in both situations, but that a far greater number of individuals were present in the deeper water. During the day-time we obtained a number of Crustaceans, several Atlanta shells, Globigerina bulloides, and the same conferva as on the previous day. After dark I got a great quantity of highly phosphorescent Crustaceans, and one small cuttle-fish.

      On the 20th the trade wind returned in full force, and the monotony of an otherwise uneventful day was varied by the appearance of a shoal of porpoises, which accompanied us for some time, moving along abreast of us and about two hundred yards off on our starboard beam, and making themselves conspicuous by their usual frisky behaviour.

      

      On the afternoon of the 22nd the high land of San Antonio, the most northerly of the Cape de Verde Islands, hove in sight, far away on our starboard bow; but the evening closing in thick and dark, and this group being almost without lighthouses, the captain decided on laying-to until next morning. When about twenty miles off, we received СКАЧАТЬ