The fifteenth century brought a change in castle-building. The accommodation of the keeps was circumscribed and the paucity of rooms made privacy impossible. One way of extending the space was, as we have said, by adding a wing at one corner. Another mode was to utilise the surrounding wall, for the keeps were generally guarded by a wall, which formed a courtyard or barmekin for stabling and offices. This was often of considerable extent and defended by towers. As the country progressed and manners improved, buildings were extended round the inside of the courtyard walls. In the sixteenth century the change went further and developed into the mansion-house built round a quadrangle. The building was first in the centre of the surrounding wall; ultimately the courtyard was absorbed and became the centre of the castle. Balquhain Castle in Chapel of Garioch, two miles from Inverurie, was originally a keep like Drum, but being destroyed in 1526, it was rebuilt. Very little of it now remains but its massive, weather-stained walls have a commanding effect. The barmekin is still traceable. Queen Mary is said to have passed the night prior to the Battle of Corrichie at Balquhain. It was burned in 1746 by the Duke of Cumberland. Many other castles on the same general plan are dotted up and down the county. Some are in ruins, some have been altered and added to on other lines, but the original keep is still a marked feature in most of them. Cairnbulg—recently restored—on the north-east coast has a keep of the fifteenth century with additions of a century later. Gight, now ruinous, but formerly celebrated for its great strength, occupies a fine site on the summit of the Braes of Gight, which rise abruptly from the bed of the Ythan. It also is a fifteenth century edifice built on the =L= plan. It has a historical interest as having once belonged to Lord Byron’s mother, from whom it was purchased by the Earl of Aberdeen. Another of the same kind is Craig Castle in Auchindoir. It was completed in 1518 and is also on the =L= plan. So too is Fedderat in New Deer. [Illustration: The Old House of Gight]