six valves, which will open downwards to let water
out, but which won't open upwards to let it in. Now, suppose a huge
billow topples into the boat and fills it quite full, is it not obvious
that all the water in the boat stands _above_ the ocean's level--being
above the boat's floor? Like a wise element, it immediately seeks its
own level by the only mode of egress--the discharging tubes; and when it
has found its level, it has also found the floor of the boat. In other
words, it is all gone! moreover, it rushes out so violently that a
lifeboat, filled to overflowing, frees itself, as I have already said,
in less than one minute!

The _buoyancy_, therefore, of a lifeboat is not affected for more than a
few seconds by the tons of water which occasionally and frequently break
into her. To prove this, let me refer you again to the account of the
Constance, given by its gallant coxswain, as recorded in the third
chapter. He speaks of the lifeboat being "buried," "sunk" by the wave
that burst over the bow of the Stanley, and "immediately," he adds, "the
men made a grasp for the spare oars!" There is no such remark as "when
we recovered ourselves," etcetera. The sinking and leaping to the
surface were evidently the work of a few seconds; and this is indeed the
case, for when the force that sinks a lifeboat is removed, she rises
that instant to the surface like a cork, and when she tumbles over she
recovers herself with the agility of an acrobat!

The transporting-carriage is a most essential part of a lifeboat
establishment, because wrecks frequently take place at some distance
from a station, and prompt assistance is of the utmost importance in all
cases of rescue. It is drawn by horses, and, with its exceedingly broad
and strong wheels, can be dragged over any kind of road or across soft
sand. It is always backed into the surf so deep that the boat may be
launched from it, with her crew seated, and the oars out, ready to pull
with might and main the instant the plunge is made. These first strokes
of a lifeboat's crew are of immense importance. Want of union or energy
on the part of steersman or crew at this critical point may be fatal.
The boat must be made to cut the breakers end-on, so as to prevent her
turning broadside on and being rolled back on the beach. Even after
these initial strokes have been made successfully, there still remains
the possibility of an unusually monstrous wave hurling the boat back e