ock and
fastened in there with lead; that's the fixed end of the boom. The other
end, which is swung backward and forward when the ships go in port, has
got a big chain too. It goes under an iron bar which is bent, and the
two ends fastened in a rock. When they want to fix the boom the end
of the chain is passed under this iron loop and then fastened to some
blocks and ropes worked from the battery above, and the end of the chain
is drawn up tight there, so that there is no loosing the chain till that
battery is taken.'

"'And you say the guns of the lower batteries at the inner point sweep
the entrance?'

"'They do, sir. There are ten of them on each side, twelve pounder
carronades, which are always charged, and crammed up to the muzzle with
bullets and nails and bits of iron. The batteries on the top of the
cliff at the entrance are the heaviest metal. They have got twenty guns
in each of them. They are loaded with round shot to keep a vessel from
approaching, though of course they could fire grape into any boats they
saw coming in.'

"'This does not seem an easy business by any means, Mr. Earnshaw,' the
captain said.

"'It does not, sir,' the lieutenant agreed in a dubisome sort of way;
'but no doubt it can be done, sir--no doubt it can be done.'

"'Yes, but how?' the captain asked. 'You will be in command of the
boats, Mr. Earnshaw, and it will never do to attack such a place as that
without some sort of plan.'

"'What is the boom like, my lad?' the lieutenant asked; 'is it lashed
together?'

"'No, it is a solid spar,' I said. 'The entrance is not more than forty
feet wide, and the boom is part of the mainmast of a big ship.'

"'It seems to me,' said the lieutenant, 'that the only way to get at it
would be to go straight at the boom, the two lightest boats to go first.
The men must get on the spar and pull the boats over, and then make a
dash for the batteries; the heavy boats can follow them.'

"'It would never do, Mr. Earnshaw,' the captain said. 'You forget there
are twelve guns loaded to the muzzle with grape and musketballs all
trained upon a point only forty feet across. Would it be possible to
land just outside the boom, lad, on one or both sides, and to keep along
the edge, or wade in the water to the batteries?'

"'No, sir, the rock goes straight up from the water both sides.'

"'Well, the two sentries, how do they get down to the water's edge?'

"'They are let down by rope from above, sir, a