A TOPOGRAPHICAL STUDY OF EBETRIA. 113

tending across the wall at this point W, and a piece of wall leads from
the main line a few feet within the city. The stones in the main wall
to the east of TFare decidedly polygonal, and are of a different quality
from those previously observed. The thickness of the wall is 2.1 m.
This measure is characteristic of the acropolis-wall through its entire
length. In the steepest portions of the ascent it contracts to 2 m., and
in one or two places, as at b and /, it is much thicker for a short dis-
tance ; this extra thickness is to give the wall the strength of a tower.
The filling is composed almost entirely of small stones. From X to Z
the grade is 10°. At Z begins a fine polygonal wall some 2 m. high.
From Z to a, the angle of elevation is 17°. At a, the line turns and
goes up the steepest portion of the ascent at an angle of 25°. A view
(plate VI) of the wall beyond b on the map gives an excellent idea of
the appearance of the main acropolis-wall in its entire extent. Towers
are not placed at regular intervals, but occur apparently where most
necessary. From W to Z, unimportant remains of these defenses exist.
Some 20 m. beyond Z is a tower 6.1 m. by 5 m. in area. The view
given in Platje VII shows its great strength and the decidedly poly-
gonal nature of the construction. The stone used is the same as the
bed-rock over which the wall extends, and was apparently quarried
on the spot. It is dark-grey, porous, and usually much Aveathered,
so much so as to be exceedingly rough and unpleasant to the touch,
contrasting decidedly with the stone in the walls on the plain. A com-
parison of plates VI and vn with the polygonal walls of Lcpreum
in Elis, of Asea near Tripolis, of Midea (?) in the Argolic plain, and of
the well-known piece of polygonal wall on the side of the city opposite
the " Treasury of Atreus," at Mycenae, shows that, so far as appear-
ances go, the oldest portion of the acropolis-wall of Eretria displays
a more decidedly polygonal character, and hence, in accordance with
the old-time view, should be of a higher antiquity than any of these.
Though no one would claim to-day that this appearance of hoary age
shows of itself that these \valls were constructed at any particular
period before the Christian era, still, when taken in connection with
other facts to be noted later, the comparison affords a strong presump-
tion that the Eretrian acropolis was fortified at an early date.

Between a and b, when the summit is nearly reached, two walls
branching from the main line claim attention. The one which crosses
the southern portion of the summit till it joins the eastern wall of the
acropolis, will be discussed further on. Just beyond where this leaves