NORHAM, Northumberland (Fig. 22).--The first castle here was built by Ranulf Flambard, Bishop of Durham, in the reign of William Rufus. It was built to defend Northumberland against the incursions of the Scots, and we are expressly told that no castle had existed there previously.[520] This first castle, which we may certainly assume to have been of earth and wood, was destroyed by the Scots in 1138, and there does not seem to have been any stone castle until the time of Bishop Puiset or Pudsey, who built the present keep by command of King Henry II.[521] Mr Clark tried hard to find some work of Flambard's in this tower, but found it difficult, and was driven back on the rather lame assumption that "the lapse of forty [really fifty at least] years had not materially changed the style of architecture then in use."[522] In fact, the Norman parts of this keep show no work so early as the 11th century, but are advanced in style, for not only was the basement vaulted, but the first floor also. The simple explanation is that Flambard threw up the large square motte on which the keep now stands, and provided it with the usual wooden defences. It also had a strong tower, but almost certainly a wooden one; hence it was easily destroyed by the Scots when once taken.[523] The motte was probably lowered to some extent when the stone keep was built. It stands on a high bank overlooking the Tweed, and is separated from its bailey by a deep ditch. The bailey may be described as a segment of a circle; its area is about 2 acres.