War has two sides--attack and defence. New ways of attacking and
defending are continually devised. When the art of defence is more
perfect than the art of attack, the world changes very little, for
the strong can keep what he has gained. When the art of attack is
the more perfect, new men have a better chance, and many changes are
made. The chief source of defence was the castle, the chief weapon
of attack was the long-bow. Wales contains the most perfect castles
in this country; it is also the home of the long-bow. From 1066 to
1284 England and Wales were conquered, and the conquest was permanent
because castles were built. From 1284 to 1461, England and Wales
attacked other countries, and the weapon which gave them so many
victories was the long-bow.

I will tell you about the castles first, about the Norman castles and
about the Edwardian castles.

The Norman castle was a square keep, with walls of immense thickness,
sometimes of 20 feet. But if the Norman had to build on the top of a
hill or on the ruins of an old castle, he did not try to make the new
castle square, but allowed its walls to take the form of the hill or
of the old castle; and this kind of castle was called a shell keep.
The outer and inner casing of the wall would be of dressed stone, the
middle part was chiefly rubble. At first, if they had plenty of
supplies, a very few men could hold a castle against an army as long
as they liked. These were the castles built by the Norman invaders
to retain their hold over the Welsh districts they conquered.

But many ways of storming a castle were discovered. They could be
scaled by means of tall ladders, especially in a stealthy night
attack. Stones could be thrown over the walls by mangonels to annoy