50
to fill up the interstices. In addi-
of oyster
tion to this the mortar was shell limes not bydraulic and of
such inferior qualityz
in
heither
woo
to crumble
pressure.
the hand under moderate
there a
any backing what soever earth and stones and in some plaus brick bat and building debris, having
been simply thrown in behind the ball and perhaps punned down.
The face stoves
in
layers.
WUR
principally stretchers; headers the
whole depth of the wall occurring only here and there at intervals
be noticed in the photo.
#21€
mary graph in the sixth course
from
the top. The horizontal beds of
the stretchers only extended
many of back from the ball face for three
or