TABLE OF CONTENTSCHAPTER PAGE[I.][Natural Fortresses Strengthened]1[II.][Fortified Hill-Tops]13[III.][Simple Artificial Enclosures]33[IV.][The Motte and Bailey Castle]48[V.][The Shell Keep]64[VI.][The Rectangular Keep]76[VII.][The Cylindrical Keep]101[VIII.][The Concentric Castle]110[IX.][The Castellated Mansion]147[X.][The Castles of Scotland]173[XI.][The Siege and Defence of a Medieval Castle]188 [INDEX]201