Tantallon Castle is of the courtyard type, similar to Caerlaverock and Doune, and was erected about the end of the fourteenth century. Situated upon a rocky precipitous site, with three sides washed by the North Sea, it was only imperative to construct defences upon the fourth or west side. A deep ditch cut in the rock, curtain walls 12 feet thick and 50 feet high, battlemented, with a level court in front, beyond which was another deep ditch,--these were the defences deemed all-sufficient to baffle intruders. The Keep also acted as a flanking defence to the curtain walls, and contained the only entrance, which passed completely through it. Many traces exist of the work carried out in the early part of the sixteenth century in the endeavour to make it impregnable to artillery. The buildings now occupy only two sides of the interior quadrangle, the rest having been dismantled. [Illustration: DUNNOTTAR CASTLE, KINCARDINESHIRE.] In the rich history of the Castle we find that in 1528 James V. invested it with 20,000 men and a formidable battering train, the structure itself being supplied with large artillery. The siege lasted twenty days and proved unavailing, the great thickness of the walls resisting the efforts of the gunners. It underwent another siege in 1639 when the Earl of Angus made a stand in it against the Covenanters. General Monk invested it and found after two days that his mortars had no effect; he then tried heavy siege guns which breached the wall, but the garrisons retreated into the central tower where they were safe, and were allowed to capitulate upon good terms. The fortress fell into ruin in the beginning of the eighteenth century. CHAPTER XI THE SIEGE AND DEFENCE OF A MEDIEVAL CASTLE A work upon castellation would undoubtedly be incomplete if it omitted to deal with the interesting subject of the means by which the medieval knight defended his castle, and of the methods he employed for attacking his neighbour's, or an enemy's town, whether in a private feud or legitimate warfare. Through the almost universal habit of perusing medieval romances the general public has formed a mental picture of the hero and his followers riding round a castle and summoning it to surrender, or challenging the garrison to emerge from their retreat and essay mortal combat in the open. As the engineer and captain of the sappers and miners, the director of the artillery, the designer of movable towers, and the general head of the various artifices calculated to bring the besieged to their senses, the hero is less well known.