in Zoology. See Felis, Mammalia Index.

in sea affairs, a ship employed in the coal trade, formed from the Norwegian model. It is distinguished by a narrow stern, projecting quarters, a deep whale, and by having ornamental figures on the prow. These vessels are generally built remarkably strong, and carry from four to six hundred tons, or, in the language of their own mariners, from 20 to 30 keels of coals.

is also a sort of strong tackle, or combination of pulleys, to hook and draw the anchor perpendicularly up to the cat-head. See CAT-HEADS.

CAT'S EYE, or Sun-stone of the Turks, a kind of gem found chiefly in Siberia. Cat's eye is by the Latins called oculus cati, and sometimes onycopalus, as having white zones or rings like the onyx, and its colours variable like opal, from which last it differs chiefly by its superior hardness. It is very hard, and semitransparent, and has different points, from whence the light is reflected with a kind of yellowish radiation somewhat similar to the eyes of cats, from whence it had its name. The best of them are very scarce, and jewellers cut them round to the greatest advantage. One of these stones, an inch in diameter, was in the possession of the duke of Tuscany.

CAT-SILVER, in Ichthyology. See Squalus, Ichthyology Index.

CAT-GUT, a denomination given to small strings for fiddles, and other instruments, made of the intestines of sheep or lambs, dried and twisted together, either singly, or several together. These are sometimes coloured red, sometimes blue, but are commonly left whitish or brownish, the natural colour of the gut. They are also used by watchmakers, cutlers, turners, and other artificers. Great quantities are imported into England, and other northern countries, from Lyons and Italy.

CAT-HARPSING, a purchase of ropes employed to brace in the throats of the lower masts behind their yards, for the double purpose of making the throats more tight, and of affording room to draw in the yards more obliquely, to trim the sails for a side-wind, when they are said to be close hauled.

CAT-HEADS, two strong short beams of timber, which project almost horizontally over the ship's bows on each side of the bowsprit; being like two radii which extend from a centre taken in the direction of the bowsprit. That part of the cat-head which rests upon the forecastle, is securely bolted to the beams; the other part projects like a crane, as above described, and carries in its extremity two or three small wheels or sheaves of braids or strong wood, about which a rope called the cat-fall, passes and communicates with the cat-block, which also contains three sheaves. The machine formed by this combination of pulleys is called the cat, which serves to pull the anchor up to the cat-head, without tearing the ship's sides with its flukes. The cat-head also serves to suspend the anchor clear of the bow, when it is necessary to let it go: it is supported by a foot of knee, which is generally ornamented with sculpture. See Plate CXXXVI.

The cat-block is filled with a large and strong hood, which catches the ring of the anchor when it is to be drawn up.

CAT-MINT. See Mentha, Botany Index.

CAT-SALT, a name given by our salt workers to a very beautifully granulated kind of common salt. It is formed out of the bittern, or leach brine, which runs from the salt when taken out of the pan. When they draw out the common salt from the boiling pans, they put it into long wooden troughs, with holes bored at the bottom for the brine to drain out; under these troughs are placed vessels to receive this brine, and across them small sticks to which the cat-salt affixes itself in very large and beautiful crystals. This salt contains some portion of the bitter purging salt, is very sharp and pungent, and is white when powdered, though pellucid in the mass. It is used by some for the table, but the greatest part of what is made of it is used by the makers of hard soap.

CAT-SILVER. See Mica.

CATACOUSTIC CURVES, in the higher geometry, that species of caustic curves which are formed by reflection. See FLUXIONS.