ABANDONMENT OF A VESSEL. Deserting and abandoning her by reason of unseaworthiness or danger of remaining in her, also when grounded and cannot be saved. This never occurs but in imminent cases; therefore, before the insured can demand recompense from the underwriter, they must cede or _abandon_ to him the right of all property which may be recovered from shipwreck, capture, or any other peril stated in the policy. Other parties entering and bringing the vessel into port obtain salvage. (_Vide_ DERELICT.) ABASE, TO. An old word signifying to lower a flag or sail. _Abaisser_ is in use in the French marine, and both may be derived from the still older _abeigh_. _Abase_ literally means to cast down, to humble. ABATE, TO. An old Anglo-Norman word from _abattre_, to beat down or destroy; as, to _abate_ a castle or fort, is to beat it down; and a gale is said to _abate_ when it decreases. The term is still used in law. ABATEMENT. A plea by which a reduction of freight is demanded, when unforeseen causes have delayed or hindered the performance of a stipulated charter-party. ABATIS. An obstruction used in temporary fortification, composed of felled trees deprived of their smaller branches, and secured to the ground side by side with their tops towards the enemy; applicable to the front of posts, works, or positions, and occasionally to the bars of rivers. ABBEY-LUBBER. This is an old term of reproach for idleness, and is here quoted only as bearing upon the nautical lubber. In the "_Burnynge of Paule's Church_, 1563," it is thus explained--"An Abbey-lubber, that was idle, well-fed, a long lewd lither loiterer, that might worke, and would not." ABBLAST. Cross-bow; hence, ABBLASTER. Cross-bow man. ABBROCHYN. The old term for beginning or broaching a barrel, cask, or any "vesselle of drynke." ABEAM. In a line at right angles to the vessel's length; opposite the centre of a ship's side. ABEAM-ARM. For this curved timber, _see_ FORK-BEAMS. ABER. An ancient British word for the mouth of a river--as Aber-brothick, Aber-avon, Aber-ystwith, and Aber-conway, &c. It also means the confluence of two or more streams. ABERRATION. An apparent change of place, or alteration of their mean position, in the fixed stars, caused by the earth's orbital movement.--_Aberration of a planet_ signifies its progressive geocentric motion, or the space through which it appears to move, as seen from the earth, during the time which light occupies in passing from the planet to us.--_Crown of aberration_ is a spurious circle surrounding the proper disc of the sun.--_Constant of aberration_, or amount of displacement in the sun's longitude, arising from the progressive motion of light, is established at 20″·45. ABET, TO. To excite or encourage--a common word, greatly in use at boat-racings, and other competitive acts. ABITED. A provincial term for _mildewed_.