In Fig 3, there is a contact scale reproduc-
tion of a stereogram of the pavement sample
of which a formline plot is reproduced in
Fig 4. In this stereogram the object incorpo-
rates the gridplate replica to which refererce
has been made, giving adequate and accurate
planimetric control, while some height control
is provided by arrangements of gauge blocks
standing on that gridplate replica, the sur-
faces of which envelop the height range of
the pavement sample. Against each gaugeblock
arrangement the height dimensions of each
block comprising that arrangement were recor-
ded in the units (inches or millimetres) in
which they were known.
Fig 3 Contact-scale reproduction of stereogram of pavement
sample of which a formline plot is reproduced in Fig 4.
Observation of these stereograms was performed on nega-
tives in the WILD A.10 Autograph. The gridplate replica
and gaugeblocks used as control data may be seen
FORMLINE PLOT OF PART OF
CRUSHED AGGREGATE SAMPLE
FORMLINE INTERVAL IMM (0:5 MM. AUXILIARY )
SCALE IN MILLIMETRES
0 10 30
Fig 4 Reproducti
SCALE IN MILLIMETRES
on of a fairdrawing of a formline plot of
the pavement sample of which the stereogram is repro-
duced in Fig 3. The formline interval is half a
millimetre on the faces of individual pieces of
aggregate