Angle of the flank exterior, is that which is before the centre of the curtain, formed by the prolongation of the faces of the bastion, or by both the fichant lines of defence, intersecting each other on planning a fortification.
Angle of the flank interior, is formed by the flanked line of defence and the curtain; being that point where the line of defence falls upon the curtain.
Angle of the line of defence, is that angle made by the flank, and the line of defence.
Angle of the face, is formed by the angle of the face and the line of defence produced till they intersect each other.
Angle of the base interior, is the half of the figure, which the interior polygon makes with the radius, when they join each other in the centre; intersecting the centre of the gorges of each bastion.
Angle of the base exterior, is an angle formed by lines drawn from the centre of the figure, to the angle of the exterior polygon, cutting the centre of the gorges of each bastion.
Angle of the gorge, is that angle formed by the prolongation of the curtains, intersecting each other, in the centre of the gorge, through which the capital line passes.
Angle of the ditch, is formed before the centre of the curtain, by the outward line of the ditch.
Angle of the mole, is that which is made before the curtain where it is intersected.
Flanked Angle. See [Angle of the bastion].