The building was large and irregular, and had been added to at various times, the hall, looking over the river, forming its most conspicuous portion; but it had not originally been built for purposes of defence, and could not have endured the Danish assault for a moment, but for external defences, utterly independent of the building, which had been recently added; a mound, surmounted by crossed palisades, skilfully strengthened by osier bands, and a deep outer ditch, now full of snow, surrounded the building on three sides. The fourth was defended by the river, which, being full owing to the late rains, rushed impetuously along below.