id of lightships, as well as of buoys and
beacons, may be made clear by a simple statement of the names of some of
the obstructions which lie in the mouth of the Thames. There are the
_Knock_ Shoals, the East and West _Barrows_, the _John_, the _Sunk_, the
_Girdler_, and the _Long_ Sands, all lying like so many ground sharks
waiting to arrest and swallow up passing vessels, which, unfortunately,
they too often accomplish despite the numerous precautions taken to rob
them of their prey. Most people know the appearance of buoys, but we
dare say few have seen a buoy or beacon resembling the one in our
engraving, which is a sort of cage, fastened to a buoy, with a bell
inside that rings by the action of the waves. It must have been
something of this sort that was used at the famous "Bell Rock" in days
of yore.

Lightships are usually clumsy-looking, red-painted vessels, having one
strong mast amidships, with a ball at the top, about six feet in
diameter, made of light laths. This ball is a very conspicuous object,
and clearly indicates a lightship to the passing vessel during the day.
At night a huge lantern traverses on, and is hoisted to nearly the top
of, the same mast. It is lighted by a number of argand lamps with
powerful reflectors. Some lightships have two masts, and some three,
with a ball and a lantern on each. Some of these lanterns contain
fixed, others revolving lights--these differences being for the purpose
of indicating to seamen the particular light which they happen to be
passing.

Thus, the Goodwin Sands, which are upwards of ten miles in length, are
marked by three lightships. The one on the north has three masts and
three _fixed_ lights. The one on the south has two masts and two
_fixed_ lights. The one that lies between the two--off Ramsgate, and
named the Gull--has one mast and one _revolving_ light.

The crew of a lightship consists of about nine or ten men, each of whom
does duty for two months on board, and one month on shore, taking their
turn by rotation; so that the number of men always on board is about
seven. While on shore, they attend to the buoys, anchors, chain-cables,
and other stores of the Trinity House, which has charge of all the
lights, buoys, and beacons in England. They also assist in laying down
new buoys and sinkers, and removing old ones, etcetera.

Lightships run considerable risk, for besides being exposed at all times
to all the storms that rage on our shores,