Page:The castellated and domestic architecture of Scotland from the twelfth to the eighteenth century (1887) - Volume 1.djvu/122

 FIRST PERIOD 102 BOTHWELL CASTLE through the stone filler into it, and so carried by a drain to the moat, which in this way would be well washed out, and the waste water dis- charged through the aperture above described ; or the water may have been stored in a tank, and occasionally let off through the moat, when both tank and moat would be cleaned out. FIG. 78. Bothwell Castle. Buttress at East End of North Wall. There is a postern door from the moat leading to the external ditch (see Fig. 72), which has been provided with a portcullis, besides two doors with strong bars. The two upper floors of the donjon (Fig. 75) communicate by the passages in the south curtain with the south parapet walks, but the com- munication is very strongly defended with doors and narrow sloping passages. There was usually in castles of this type a private way of escape from the donjon, and it seems in this case to have been by these passages to the parapet and tower adjoining, and thence by the