got its own particular mark. These are known to the masters of all
ships that go up and down the river, and so they can tell exactly
where they are, and what course to take. At night they anchor, for
there would be no possibility of finding the way up or down in the
dark. I have heard tell from mariners who have sailed abroad that
there ain't a place anywhere with such dangerous sands as those we
have got here at the mouth of the Thames."

In the first three or four hours' sail Geoffrey and Lionel acquired
much nautical knowledge. They learned the difference between the
mainmast and the mizzen, found that all the strong ropes that kept
the masts erect and stiff were called stays, that the ropes that
hoist sails are called halliards, and that sheets is the name given
to the ropes that restrain the sails at the lower corner, and are
used to haul them in more tightly when sailing close to the wind,
or to ease them off when the wind is favourable. They also learned
that the yards at the head of the main and mizzen sails are called
gaffs, and those at the bottom, booms.

"I think that's about enough for you to remember in one day, young
masters," John Lirriper said. "You bear all that in your mind,
and remember that each halliard and sheet has the name of the sail
to which it is attached, and you will have learnt enough to make
yourself useful, and can lend a hand when the skipper calls out,
`Haul in the jib sheet,' or `Let go the fore halliards.' Now sit
yourselves down again and see what is doing. That beacon you can
just see right ahead marks the end of the Whittaker Spit. When we
get there we shall drop anchor till the tide turns. You see we are
going across it now, but when we round that beacon we shall have it
dead against us, and the wind would be too light to take us against