shoals and sand everywhere, blocking nine-tenths of the land
altogether, and doing their best to block the other tenth where the
great rivers run in. Now let's take it bit by bit. You see it divides
itself into three. Beginning from the west the _first piece_ is from
Borkum to Wangeroog--fifty odd miles. What's that like? A string of
sandy islands backed by sand; the Ems river at the western end, on
the Dutch border, leading to Emden--not much of a place. Otherwise,
no coast towns at all. _Second piece:_ a deep sort of bay consisting
of the three great estuaries--the Jade, the Weser, and the
Elbe--leading to Wilhelmshaven (their North Sea naval base), Bremen,
and Hamburg. Total breadth of bay twenty odd miles only; sandbanks
littered about all through it. _Third piece:_ the Schleswig coast,
hopelessly fenced in behind a six to eight mile fringe of sand. No
big towns; one moderate river, the Eider. Let's leave that third
piece aside. I may be wrong, but, in thinking this business out, I've
pegged away chiefly at the other two, the seventy-mile stretch from
Borkum to the Elbe--half of it estuaries, and half islands. It was
there that I found the Medusa, and it's that stretch that, thanks to
him, I missed exploring.'

I made an obvious conjecture. 'I suppose there are forts and coast
defences? Perhaps he thought you would see too much. By the way, he
saw your naval books, of course?'

'Exactly. Of course that was my first idea; but it can't be that. It
doesn't explain things in the least. To begin with, there _are_ no
forts and can be none in that first division, where the islands are.
There might be something on Borkum to defend the Ems; but it's very
unlikely, and, anyway, I had passed Borkum and was at Norderney.
There's nothing else to defend. Of course it's different in the