They were grazing with bucolic tranquillity on the maritime pasture lands, contemplated from afar by the mussels, the oysters, and other bi-valves, attached to the rocks by a hard and horny hank of silk that enwrapped their enclosures.  Some of these shells, called hams,—­clams of great size, with valves in the form of a club,—­had fixed themselves upright in the mire, giving the appearance of a submerged Celtic camp, with a succession of obelisks swallowed up by the depths of the sea.

The one called the date-shell can, assisted by its liquid acid, pierce the hardest stone with its cylindrical gimlet.  The columns of Hellenic temples, submerged in the Gulf of Naples and brought to light by an earthquake, are bored from one end to the other by this diminutive perforator.

Cries of surprise and nervous laughter suddenly reached Ferragut.  They came from that part of the Aquarium where the fish tanks were.  In the corridor was a little trough of water and at the bottom a kind of rag, flabby and gray, with black rings on the back.  This animal always attracted the immediate curiosity of the visitors.  Everybody would ask for it.

Groups of countrymen, city families preceded by their offspring, pairs of soldiers, all might be seen consulting before it and experimenting, advancing their hands over the trough with a certain hesitation.  Finally they would touch the living rag at the bottom,—­the gelatinous flesh of the fish-torpedo,—­receiving a series of electric shocks which quickly made them loosen their prey, laughing and raising the other hand to their jerking arms.

Ulysses on reaching the fish tanks had the sensation of a traveler who, after having lived among inferior humanity, encounters beings that are almost of his own race.

There was the oceanic aristocracy, the fish free as the sea, swift, undulating and slippery, like the waves.  They all had accompanied him for many years, appearing in the transparencies opened by the prow of his vessel.

They were vigorous and therefore had no neck,—­the most fragile and delicate portion of terrestrial organism,—­making them more like the bull, the elephant and all the battering animals.  They needed to be light, and in order to be so had dispensed with the rigid and hard shell of the crustacean that prevents motion, preferring the coat of mail covered with scales, which expands and contracts, yields to the blow but is not injured.  They wished to be free, and their body, like that of the ancient wrestlers, was covered with a slippery oil, the oceanic mucus that becomes volatilized at the slightest pressure.

The freest animals on earth cannot be compared with them.  The birds need to perch and to rest during their sleep, but the fish continue floating around and moving from place to place while asleep.  The entire world belongs to them.  Wherever there is a mass of water,—­ocean, river or lake, in whatever altitude or latitude, a mountain peak lost in the clouds, a valley boiling like a whirlpool, a sparkling and tropical sea with a forest of colors in its bosoms, or a polar sea encrusted with ice and people, with sea-lions and white bears,—­there the fish always appears.