Chap. VIII. BRITAIN. 373

Each stone was separately worked on land, marked or numbered, and lines were drawnacross the middle of each, tending to the centre as well as to the concentric circles,

E

Fig. 376. THIRD COURSE.

to denote their position in the contrary direction; they also had a notch cut in the edgeswhere they were to unite with those adjoining.

Each stone had cut, from the bottom to the top of the course, two grooves, 3 inches in

E

Fig. 377.

FOURTH COURSE.

B B 3