redress the balance a little by building similar works
in America on a very much smaller scale, with a much more
purely defensive purpose, and as an altogether subsidiary
undertaking. Dunkirk was 'a pistol held at England's
head' because it was an integral part of France, which
was the greatest military country in the world and second
to England alone on the sea. Louisbourg was no American
Dunkirk because it was much weaker in itself, because it
was more purely defensive, because the odds of population
and general resources as between the two colonies were
fifteen to one in favour of the British, and because the
preponderance of British sea-power was even greater in
America than it was in Europe.

The harbour of Louisbourg ran about two miles north-east
and south-west, with a clear average width of half a
mile. The two little peninsulas on either side of the
entrance were nearly a mile apart. But the actual fairway
of the entrance was narrowed to little more than a clear
quarter of a mile by the reefs and islands running out
from the south-western peninsula, on which the fortress
stood. This low, nubbly tongue of land was roughly
triangular. It measured about three-quarters of a mile
on its longest side, facing the harbour, over half a mile
on the land side, facing the enemy's army, and a good
deal under half a mile on the side facing the sea. It
had little to fear from naval bombardment so long as the
enemy's fleet remained outside, because fogs and storms
made it a very dangerous lee shore, and because, then as
now, ships would not pit themselves against forts unless