The Heniora.

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Chap. 1.]

acts as a sucker; while that curious animal the cuttle fish secures the vic-tims that fall into its fatal embraces by the suckers on its arms.

The prodigious pressure that, at great depths, unites these inhabitants ofthe sea to their prey, led man to employ them to hu nt the seafor his benefitas well as their own. Both the remora and lamprey tribe have been usedfor this purpose. Columbus when on the coast of St. Domingo was greatlysurprised on beholding the Indians of that island fishing with them. “ Theyhad a small fish, the flat head of which was furnished with numerous suck-ers, by which it attached itself so firmly to any object as to be torn inpieces rather than abandon its hold. Tying a long String to the tail, the In-dians permitted it to swim at large : it generally kept near the surface tiliit perceived its prey, when darting down swiftly it attached itself to thethroat of a fish, or to the under shell of a tortoise, when both were drawnup by the fisherman.” Ferdinand Columbus saw a shark caught in thismanner. a

The same mode of fishing was followed at Zanguebar, on the easterncoast of Africa. The inhabitants of the coast when fishing for turtle,“ take a living sucking fish or remora, and fastening a couple of strings to it,(one at the head and the other at the tail) they let the sucking fish downinto the water on the turtle ground, among the half grown or young turtle;and when they find that the fish hath fastened himseif to the back of a tur-tle, as he will soon do, they draw him and the turtle up together. Thisway of fishing as I have heard is also used at Madagascar.” 1,

The remora was well known to the ancients. History has preserveda fabulous account of their having the power to stop a vessel under sail,by attaching themselves to her rudder. A Roman ship belonging to afleet, it is said, was thus arrested, when she “ stoode Stil as if she had lienat anker, not stirring a whit out of her place.” There is another illustra-tion of the enormous pressure that fishes endure at great depths. Thesmall volume of air that is contained in the bladder, and by the expansion* and contraction of which they ascend and descend, is at the bottom of thesea compressed into a space many times smaller than when they swimnear the surface. (At 33 feet from the surface it occupies but one half.)Hence, it frequently occurs that when such fish are suddenly drawn up,(as the cod on the banks of Newfoundland ) the membrane bursts, in con-sequence of the diminished pressure, and (he air rushing into the abdomen,forces the intestines out of the mouth. From a similar cause, blood isforced outof the ears of divers, when the bell that contains them is quicklydrawn up. This pressure is also evinced in the fact that the timber offoundered vessels never rises, because the pores become completely filledwith water by the pressure of the superincumbent mass, and the woodthen becomes almost ‘ heavy as iron.’

The pressure of the atmosphere on liquids is equally obvious. Whena bücket or other vessel is sunk in water and then raised in an invertedPosition, the air being excluded from acting on the surface of the liquidwithin, still presses on that without, so that the water is suspended in thevessel; and if the under surface of the liquid could be kept level and atrest, water might be transported in buckets thus turned upside down, aseffectually as in the ordinary mode of conveying it ’

The experiment with a goblet or tumbler presents a very neat illustra-tion. One of these filled with water, and having a piece of writing paperlaid over it, and held close tili the vessel be inverted, will retain the liquid

“Irving’s Columbus, Vol. i, 273. »Dampiev’s Voyages, Vol. ii, part ii, 108.

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