The Danes advanced to this stronghold and took possession of it, and
they made it for some time their head-quarters. It was at once the
center from which they carried on their enterprises in all directions
about the island, and the refuge to which they could always retreat
when defeated and pursued. In the possession of such a fastness, they,
of course, became more formidable than ever. King Ethelred determined
to dislodge them. He raised, accordingly, as large a force as his
kingdom would furnish, and, taking his brother Alfred as his second in
command, he advanced toward Reading in a very resolute and determined
manner.

He first encountered a large body of the Danes who were out on a
marauding excursion. This party consisted only of a small detachment,
the main body of the army of the Danes having been left at Reading to
strengthen and complete the fortifications. They were digging a trench
from river to river, so as completely to insulate the castle, and make
it entirely inaccessible on either side except by boats or a bridge.
With the earth thrown out of the trench they were making an embankment
on the inner side, so that an enemy, after crossing the ditch, would
have a steep ascent to climb, defended too, as of course it would be
in such an emergency, by long lines of desperate men upon the top,
hurling at the assailants showers of javelins and arrows.

While, therefore, a considerable portion of the Danes were at work
within and around their castle, to make it as nearly as possible
impregnable as a place of defense, the detachment above referred to
had gone forth for plunder, under the command of some of the bolder
and more adventurous spirits in the horde. This party Ethelred
overtook. A furious battle was fought. The Danes were defeated, and