SEA-TANG. Tangle, a sea-weed.

SEAT-LOCKERS. Accommodations fitted in the cabins of merchantmen for sitting upon, and stowing cabin-stores in.

SEAT OF WATER. Applies to the line on which a vessel sits.

SEA-TRANSOM. That which is bolted to the counter-timbers, above the upper, at the height of the port-sills.

SEA-TURN. A tack into the offing.

SEA-URCHIN. The Echinus, an animal of the class Echinodermata, of globular form, and a hard calcareous outer covering, beset with movable spines, on the ends of which it crawls about.

SEA-WALLS. Elevations of stones, stakes, and other material, to prevent inundations.

SEA-WARD. Towards the sea, or offing.

SEA-WARE. The sea-weed thrown up by surges on a beach.

SEA-WATER. "The quantity of solid matter varies considerably in different seas, but we may assume that the average quantity of saline matter is 31⁄2 per cent., and the density about 1·0274" (Pereira). The composition of the water of the English Channel according to Schweitzer is—