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he has brought together concerning the oceanic birds, in particular, appears to be highly curious. We shall not, however, in this place, consider critically what additions he has made to the materials of science strictly so called-we mean as to the addition of species, if not of genera, to the zoological system; but afford the general reader some specimens of the style in which he describes those incidents of his life at sea which he has turned to solid account in the technical sections of his Appendix.

We begin with a paragraph or two on that well-known phenomenon which has so long perplexed and divided our philosophers, the peculiar phosphoric light given out by the ocean, more especially and more brilliantly in tropical regions, during the absence of the sun's rays. Mr. Bennett had one splendid opportunity of witnessing this effect when traversing the bay of Manilla. He thus writes :

'The wake of the vessel is one broad sheet of phosphoric matter, so brilliant as to cast a dull, pale light over the after-part of the ship; the foaming surges, as they gracefully curl on each side of the vessel's prow, are similar to rolling masses of liquid phosphorus; whilst in the distance, even to the horizon, it seems an ocean of fireand the distant waves, breaking, give out a light of inconceivable beauty.'-vol. i. p. 36.

'It must not be for a moment conceived that the light described as like to a sea of "liquid fire," is of the same character as the flashes produced by the volcano, or by lightning, or meteors. No it is the light of phosphorus, as the matter truly is, pale, dull, approaching to a white or very pale yellow, casting a melancholy light on objects around, only emitting flashes by collision. To read by it is possible, but not agreeable; and, on an attempt being made, it is almost always found that the eyes will not endure the peculiar light for any length of time, as headaches and sickness are occasioned by it.'-p. 38.

Having stated his concurrence in the opinion, that this brilliant appearance is mainly occasioned by shoals of the molluscous and crustaceous tribes, but that it may often be accounted for merely by the débris of dead animal matter with which sea-water is loaded our author gives us the result of a practical experiment of his own on the 8th of June, 1832, after a large shoal of fish had been observed:

'Late at night the mate of the watch came and called me to witness a very unusual appearance in the water, which he, on first seeing, considered to be breakers. On arriving upon the deck, this was found to be a very broad and extensive sheet of phosphorescence, extending in a direction from east to west as far as the eye could reach: the luminosity was confined to the range of animals in this shoal-there was no similar light in any other direction. I cast the towing

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net over the stern of the ship, as we approached nearer the luminous streak, to ascertain the cause of this extraordinary and so limited phenomenon. The ship soon cleaved through the brilliant mass, from which, by the disturbance, strong flashes of light were emitted; and the shoal (judging from the time the vessel took in passing through the mass) may have been a mile in breadth: the passage of the vessel through them increased the light around to a far stronger degree, illuminating the ship. On taking in the towing net, it was found half filled with pyrosoma atlanticum, which shone with a beautiful pale greenish light-and there were also a few small fish in the net at the same time; after the mass had been passed through, the light was still seen astern until it became invisible in the distance, and the whole of the ocean then became hidden in darkness as before this took place. The scene was as novel as it was beautiful and interesting, more so from having ascertained, by capturing the luminous animals, the cause of the phenomenon.'-vol. i. p. 39, 40.

Of the length to which albicores, bonitos, sharks, and dolphins will follow a ship Mr. Bennett gives us many striking instances. One albicore having been wounded on the back by some sharp instrument, leaving a noticeable scar, first caught his attention on this voyage, S° north latitude, and he continued to recognize it almost daily as far as latitude 11° south-a distance of eight hundred and fifty miles. The length of aërïal voyages accomplished by the huge albatross and other oceanic birds is even more extraordinary. In reviewing Earle's residence at Tristan d'Acunha, a few Numbers back, we extracted some curious details as to the habits of the albatross when on shore; but that writer said nothing of the real roc on the wing. Mr. Bennett says:

It is pleasing to observe this superb bird sailing in the air in graceful and elegant movements, seemingly excited by some invisible power-for there is rarely any movement of the wings seen, after the first and frequent impulses given, when the creature elevates itself in the air-rising and falling as if some concealed power guided its various motions, without any muscular exertion of its own-and then descending and sweeping the air close to the stern of the ship, with an independence of manner, as if it were "monarch of all it surveyed." It is from the very little muscular exertion used by these birds that they are capable of sustaining such long flights without repose.'—p. 45.

The largest albatross shot by Mr. Bennett during this voyage measured fourteen feet, but we have seen distinct accounts of specimens reaching across the wings to full twenty feet. He proceeds to say:

'When seizing an object floating on the water, they gradually descend with expanded or up-raised wings, or sometimes alight, and float like a duck on the water while devouring their food; then they skim

the

the ocean with expanded wings, as they run along for some distance, until they again soar in mid-air, and recommence their erratic flights. It is interesting to view them, during boisterous weather, flying with, and even against, the wind, seeming the "gayest of the gay" in the midst of howling winds and foaming waves.

To watch the flight of these birds used to afford me much amusement, commencing with the difficulty experienced by them in elevating themselves from the water. To effect this object, they spread their long pinions to the utmost, giving them repeated impulses as they run along the surface of the water. Having, by these exertions, raised themselves above the wave, they ascend and descend, and cleave the atmosphere in various directions, without any apparent muscular exertion. How then, it may be asked, do these birds execute such movements? The whole surface of the body in this, as well as, I believe, most, if not all, the oceanic tribes, is covered by numerous air-cells, capable of a voluntary inflation or diminution, by means of a beautiful muscular apparatus. By this power, the birds can raise or depress themselves at will; and the tail, and great length of the wing, enable them to steer in any direction. Indeed, without some provision of this kind to save muscular exertion, it would be impossible for these birds to undergo such long flights without repose as they have been known to do; for the muscles appertaining to the organs of flight, although large in these birds, are evidently inadequate in power to the long distances they have been known to fly, and the immense length of time they remain on the wing, with scarcely a moment's cessation.

When several species of the albatross, as well as petrels and other oceanic birds, are about the ship at the same time, no combats have been seen to take place between them; but on the death of one, the others soon fall upon and devour it.'—vol. i. pp. 46, 47.

Another great source of amusement was shark-fishing-of which sport Captain Hall's enthusiastic details must be in every reader's recollection :

The capture of one of these voracious animals frequently beguiles a tedious hour during a long voyage. Its struggles, when brought on deck, are very great, but a few severe blows on the nose soon disable it from further exertion. When seizing any object, the animal turns on the side, not (as is generally supposed) on the back. The shark, judging by an European palate, is not good eating: the fins and tail are very glutinous, and are the portions most relished by the seamen ; when dried, they form an article of commerce to China, where they are used in soups. ...... I have seen several sharks and bonitos about the ship at the same time, but I never observed the former attempt to molest the latter.

Attending the shark is seen that beautiful little fish, the gasterosteus ductor, or pilot-fish; which first approaching the bait, returns as if to give notice, when, immediately after, the shark approaches

and

and seizes it. It is a curious circumstance that this elegant little fish is seen in attendance only upon the shark. After the shark is hooked, the pilot-fish still swim about, and for some time after he has been hauled on deck; they then swim very near the surface of the water, and at that time I have seen them taken by a basket from the chains of the ship. When the shark has been hooked and afterwards escapes, he generally returns, and renews the attack with increased ferocity, irritated perhaps by the wound he has received.'-vol. ii. p. 266.

The shark, Mr. Bennett says elsewhere, is more wary of taking the bait when unaccompanied by the pilot-fish; he will then come close, and withdraw again, several times before he ventures to seize it; but when the little pilot is in company it hazards the first advances to the rancid beef or bacon, reconnoitres carefully, and at length reports the result at head-quarters, upon which the huge monster is seen at once to plunge onward, and makes his snap at the bait without hesitation.

That which is termed muscular irritability, and which is met with in all cold-blooded animals, is well exemplified in the shark, which perhaps possesses it to a greater degree than other kinds of fish. I have seen a shark transfixed with a harpoon after it had been hooked, so as to cause the viscera to protrude; it was hoisted on deck, when, after a quarter of an hour had elapsed, the lower part was separated from the upper-the detached lower portion for a long time displayed great powers of vitality;-when the head and upper portion were afterwards thrown into the water, the pectoral fins were moved as in the action of swimming. How long this irritability continued I cannot say, (but from other instances that I had seen I should consider for a long period,) as it soon went astern of the ship. I have frequently seen the animal hauled on deck, the whole of the viscera extracted, and the body, when thrown overboard, swim for some distance in this mutilated state. Again, a shark has been hung up with the abdomen ripped open, the whole of the viscera extracted, and the head detached; yet symptoms of vitality, or rather muscular irritability, remained for three hours from the time of its removal from the water; and this frequently occasions the spectators to consider that the animal is in a state of suffering. It is only in the cold-blooded animals that we meet with this to such an extent; in the warm-blooded animals it occurs, but in a very slight degree.'-Ibid. p. 270-272.

Blumenbach, in his Manual of Natural History, says,- The extraordinary strength of the reproductive power in several amphibia, and the astonishing facility with which the process is carried on, depend, if I mistake not, on the great magnitude of their nerves and the diminutive proportion of their brain. The former parts are, in consequence, less dependent on the latter:

hence

hence the whole machine has less powers of motion, and displays less sympathy; the mode of existence is more simple, and approaches more nearly to that of the vegetable world than in the warm-blooded classes; but, on the contrary, the parts possess a greater individual independent vitality. In consequence of this latter endowment, stimuli which operate on one part, or one system, do not immediately affect the whole frame by sympathy, as in warm-blooded animals; and hence it is that we are enabled to explain the peculiar tenacity of life which is displayed under various circumstances in this class-as, for example, how frogs still continue to jump about after the heart has been torn out, and turtles have lived for months after the removal of the whole brain from the cranium. The long-continued power of motion in parts which have been cut off from the body, as in the tail of the water-newt and blind-worm, is to be explained upon the same principles.'

The length of time during which this irritability exists in snakes has given rise to the opinion of the vulgar, that if a snake is killed in the morning, it will not die before sunset.' Among numerous instances of such irritability even in the warm-blooded class, the human heart, for some little time after death has taken place, may be stimulated to perform its natural action by being punctured; and in a limb after amputation, the muscles are excited to contract by the plunge of a scalpel. Of the effects of galvanism we need say nothing.

Among other marine objects discussed in this chapter, we find 'the Guinea-ship' of our old navigators-called, in the dialect of modern sailors, the Portuguese man-of-war'-that beautiful molluscous animal the physalia, of which Lamarck enumerates four species, all inhabiting the tropical seas, but some of them seen occasionally in high latitudes during the summer months. They are, of course, more readily discerned in calm weather than in strong breezes, and have then a strong resemblance to a miniature vessel resting on the surface of the waters-whence their popular names, ancient and modern. The vulgar notion that the animal has the power of voluntarily collapsing its bladder-sail, and sinking to the depths of the ocean, when danger approaches, appears to have been for ever disposed of by our author's observations. He found several thrown on the shore of New South Wales in tempestuous weather, the bladder portion still remaining inflated; and while at sea he frequently landed them on deck from his hand-net in the same condition. The inflated membrane is evidently meant merely to keep the creature buoyant on the surface, while its long tentacula are extended below in search of prey. The bladder is of a light azure hue, streaked with delicate sea-green, and

the

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