of the top-sail. It is
intended for the men at the earing in reefing, or when setting the
top-gallant-studding-sails.

HORSE-ARTILLERY. A branch of field artillery specially equipped to
man[oe]uvre with cavalry, having lighter guns, and all its gunners
mounted on horseback. Its service demands a rare combination of
soldierly qualities.

HORSE-BUCKETS. Covered buckets for carrying spirits or water in.

HORSE-BUCKLE. The great whelk.

HOUSE-COCKLE. _See_ GAWKY.

HORSE-FOOT. A name of the _Limulus polyphemus_ of the shores of America,
where from its shape it is called the horse-shoe or lantern crab.

HORSE-LATITUDES. A space between the westerly winds of higher latitudes
and the trade-winds, notorious for tedious calms. The name arose from
our old navigators often throwing the horses overboard which they were
transporting to America and the West Indies.

HORSE-MACKEREL. A large and coarse member of the Scomber family,
remarkably greedy, and therefore easily taken, but unwholesome.

HORSE-MARINE. An awkward lubberly person. One out of place.

HORSE-MUSSEL. _See_ DUCK-MUSSEL.

HORSE-POTATOES. The old word for yams.

HORSE-POWER. A comparative estimate of the capacity of steam-engines, by
assuming a certain average effective pressure of steam, and a certain
average linear velocity of the piston. The pressure multiplied by the
velocity gives the effective force of the engine exerted through a given
number of feet per minute; and since the force called a horse-power
means 33,000 lbs. acting thus one foot per minute, it follows that the
nominal power of the engine will be found by dividing the effective
force exerted by the piston, multiplied by the number of feet per minute
through which it acts by 33,000.

HORSES. Blocks in whalers for cutting blubber on. (_See_ WHITE-HORSE.)

HORSE-SHOE. In old fortification, a low work of this plan sometimes
thrown up in ditches.

HORSE-SHOE CLAMP. The iron or copper straps so shaped, used as the
fastenings which connect the gripe with the fore-foot at the scarph of
the keel and stem.

HORSE-SHOE HINGES. Those by which side-scuttles or ventilators to the
cabins are hung.

HORSE-SHOE RACK. A sweep curving from the bitt-heads abaft the main-mast
carrying a set of nine-pin swivel-blocks as the fair leaders of the
light running gear, staysail, halliards, &c.

HORSE-TONGUE. A name applied to a kind of sole.

HORSE-UP. _See_ HORSING-IRON.

HORSING-IRON. An iron fixed in a