Why 45, when the figure in the document is 44?
A coincidence? No. In all this business, there is no such thing as a
coincidence, at least not an involuntary one. Ganimard, be so good as
to move one step higher up. That's it, don't leave this forty-fourth
step. And now I will work the iron nail. And the trick's done, or I'll
eat my boots!"

The heavy door turned on its hinges. A fairly spacious cavern appeared
before their eyes.

"We must be exactly under Fort Frefosse," said Beautrelet. "We have
passed through the different earthy layers by now. There will be no
more brick. We are in the heart of the solid limestone."

The room was dimly lit by a shaft of daylight that came from the other
end. Going up to it, they saw that it was a fissure in the cliff,
contrived in a projecting wall and forming a sort of observatory. In
front of them, at a distance of fifty yards, the impressive mass of the
Needle loomed from the waves. On the right, quite close, was the arched
buttress of the Porte d'Aval and, on the left, very far away, closing
the graceful curve of a large inlet, another rocky gateway, more
imposing still, was cut out of the cliff; the Manneporte,[10] which was
so wide and tall that a three-master could have passed through it with
all sail set. Behind and everywhere, the sea.

[10] Magna porta.

"I don't see our little fleet," said Beautrelet.

"I know," said Ganimard. "The Porte d'Aval hides the whole of the coast
of Etretat and Yport. But look, over there, in the offing, that black
line, level with the water--"

"Well?"

"That's our fleet of war, Torpedo-boat No. 25. With her there, Lupin is
welcome to break loose--if he wants to study the landscape at the
bottom of the sea."

A baluster marked the entrance to the staircase, near the fissure. They
started on their way down. From time to time, a little window pierced
the wall of the cliff; and, each time, they caught sight of the Needle,
whose mass seemed to them to grow more and more colossal.

A little before reaching high-water level, the windows ceased and all
was dark.

Isidore counted the steps aloud. At the three hundred and fifty-eight,
they emerged into a wider passage, which was barred by another iron
door strengthened with slabs and nails.

"We know all about this," said Beautrelet. "The document gives us 357
and a triangle dotted on the right. We have only to repeat the
performance."

The second door obeyed like the first. A long,