of performing castle-guard, if they are willing to perform this
service. Castle-guard was the liability incumbent on the holders of
some estates to serve in the garrison of the royal castles. The
constables of these castles had adopted the custom of compelling these
landholders to give money and not service, mercenaries being then
hired to perform this.
Chapters XXX. and XXXI. forbid the royal officials to seize the horses
or carts of freemen for transport duty, or to take wood for the king's
buildings.