(_a_) A circular earthwork, 300 feet in diameter. (See page 34.)
(_b_) An avenue bounded by earthworks approaching it on the
north-east. (See page 34.)
(_c_) One large unworked Sarsen Stone, called the "Hele Stone," or
"Friar's Heel." (See page 28.)
(_d_) A recumbent slab within the earthwork called the "Slaughtering
Stone." (See page 31.)
(_e_) Two small unhewn Sarsens lying north-west and south-east of the
Circle of Stones. (See page 27.)
(_f_) A ring of hewn Sarsen stones with "imposts" or lintels mortised
to them. The lintels are fitted together with toggle joints. Sixteen
out of the original thirty uprights of these "Trilithons" are now
standing.
The diameter of this circle is about 108 feet, or that of the dome of
St. Paul's. (See page 12.)
(_g_) A ring of less perfectly hewn "Foreign Stones" (_i.e._ stones
not to be found in Wiltshire at the present day).
These numbered between thirty and forty. Only seven are standing
to-day, nine are overthrown. (See page 20.)
(_h_) Five great Trilithons, arranged in a horseshoe, with the opening
to the north-east. These Trilithons rise gradually in height towards
the south-west. The largest group of stones fell A.D. 1620. Those next
to the great Trilithon on the north-west, fell on January 3rd, 1797.
To-day only two of the Inner Trilithons are standing. One upright of
the great Trilithon (raised and made secure in 1901) is erect. (See
page 17.)
(_i_) A horseshoe of less perfectly hewn Foreign Stones. Originally
there were fifteen or more of these monoliths averaging eight feet
high. (See page 20.)
(_j_) A simple recumbent slab of micaceous sandstone called the "Altar
Stone." (See page 14.)