HOLLOW SEA. The undulation of the waves after a gale; long hollow-jawed sea; ground-swell.
HOLLOW SHOT. Introduced principally for naval use before the horizontal firing of shells from guns became general. Their weight was about two-thirds that of the solid shot; thus they required less charge of powder and weight of gun than the latter, whilst their smashing effect and first ranges were supposed to be greater. It is clear, however, that if filled with powder, their destructive effect must be immensely increased.
HOLLOW SQUARE. The square generally used by British infantry; a formation to resist cavalry. Each side is composed of four ranks of men, the two foremost kneeling with bayonets forming a fence breast high; the inclosed central space affords shelter to officers, colours, &c. With breech-loading muskets this defence will become less necessary. (See also [Rallying Square].)
HOLM. (See [Clett].) A name both on the shores of Britain and Norway for a small uninhabited island used for pasture; yet in old writers it sometimes is applied to the sea, or a deep water. Also, an ill-defined name applied to a low islet in a river, as well as the flat land by the river side.
HOLOMETRUM GEOMETRICUM. A nautical instrument of brass, one of which, price £4, was supplied to Martin Frobisher in 1576.
HOLSOM. A term applied to a ship that rides without rolling or labouring.
HOLSTER. A case or cover for a pistol, worn at the saddle-bow.
HOLT [from the Anglo-Saxon]. A peaked hill covered with a wood.
HOLUS-BOLUS. Altogether; all at once.
HOLY-STONE. A sandstone for scrubbing decks, so called from being originally used for Sunday cleaning, or obtained by plundering churchyards of their tombstones, or because the seamen have to go on their knees to use it.