Block House
a fortified edifice of one or more stories, constructed chiefly of blocks or hewn timber. Block houses are supplied with loopholes for musketry and sometimes with embrasures for cannon, and when of more than one story the upper ones are made to overhang those below, and are furnished with machicolations or loopholes in the overhung floor, so that a perpendicular fire can be directed against the enemy in close attack. In the World War (1914- 1918) the Germans used concrete block houses in northern France to defend their front lines.