r or slip.

THROT. That part of the mizen-yard close to the mast.

THROTTLE-VALVE. A valve in the steam-pipe of an engine for preventing
the escape of steam, or regulating the velocity of its passage from the
boiler to the cylinder.

THROUGH ALL. Carrying canvas in heavy squalls without starting a stitch.
It demands not only courage, but seamanlike judgment. Also applied to
the cable, or any purchase where, by reason of its slipperiness, the
purchase does not nip; she is then said to be "heaving through all."
"Fresh nippers, thick and dry, for weighing," are then called for, and
sand applied to overcome the slipping.

THROUGH FASTENINGS. Applied to bolts and tree-nails driven through both
the timber and plank of the sides.

THROUGH-PIECES. _See_ GRAVING-PIECES.

THROUGH THE FLEET. A seaman's being sentenced by court-martial to be
towed by a boat from every ship through the fleet, and receive alongside
each a proportion of the lashes to be inflicted. But this was only
awarded where the offence deserved a less punishment than death, and is
now discontinued, solitary confinement or penal servitude being
substituted.

THROW. A cast of the hand-lead.

THROWING A STEAM-ENGINE OUT OF GEAR. Disconnecting the eccentric rod
from the gab-lever.

THRUM. Any coarse woollen or hempen yarn. It is used for mops, &c., in
the cabins; also for mats, which are worked on canvas with a large
bolt-rope needle.--_To thrum._ A vessel, when leaky, is thrummed by
working some heavy spare sail, as the sprit-sail, into a thrummed mat,
greasing and tarring it well, passing it under the bottom, and heaving
all parts tight. The pressure forces the tarred oakum into the openings,
and thus, in part, arrests the ingress of water.

THRUMMED MAT. A small mat faced with rope-yarn or spun yarn, which is
used in a vessel's rigging to prevent chafing.

THRUST. The effort of a screw-propeller.

THUD. The sound of a bullet on hitting the intended object.

THULE [Gaelic _thuath_]. An extreme object to the north.

THUMB-CLEAT. In shape resembling a thumb. They arrest the
topsail-reef-earings from slipping, and are also lashed to the rigging
with a hollow, cut out to act as a hook, to suspend the bight of a rope,
as the truss-pendants on the lower masts.

THUNDERING. A sailor's emphatic word for anything choice, large, fine,
or powerful.

THUNDER SQUALL. This is similar to the black squall, only that it is
always preceded and attended by lightn