Agriculture Reference
In-Depth Information
This definition, and the description by Pasley (1826, 241), 'A brick axe to com-
plete the cutting begun by the saw. It has an edge at each end, like a very large
chisel, with a round stem in the centre for grasping it. It is used by striking down
over a chopping block', reveals the changed use of the tool. Clearly its long chisel-
type blade design and heavier weight was intended to 'cleave' bricks in a manner
akin to a chopper splitting timber. This brick axe is incapable of trimming and
dressing rubbing bricks to cut-moulded shapes as its smaller predecessor.
A large brick axe was forged, by a traditional blacksmith, as part of the
author's research, following the exact specification given by Lloyd, and used in
a series of trials to determine its performance in the manner described above.
These trials were carried out using different rubbing and soft handmade bricks,
using a grub saw and a chopping block of 75mm thick timber. The intention
being to determine the practicality of the above quoted axing technique, assess
the overall effectiveness of the brick axe, and finally judge the speed a hewer
could both cleave a brick to shape and rub its surface flat.
In all tests the grub saw was used first to cut a 6-10mm deep groove all
around the brick, defining the waste portion to be cut away. Stood upright on
the chopping block, the brick axe blade was then located centrally into the saw
cut on the brick. Initially it was noted that the sharpened end of the brick axe
blade was only penetrating about 2mm into this cut because of the bevelled
edge thickness (5 mm) of the brick axe blade. The blade was 'shouldering' and
not fully entering the saw cut. It was decided to proceed. With the brick held
by the left hand and the brick axe held vertically with the right, the two were
raised simultaneously about 50 mm off the chopping block and brought down
smartly upon it (Fig. 99).
The results were most revealing. With modern harder rubbers, the brick axe
simply 'cleaved-out' sizeable chunks of material, failing to cut through the brick
from top to bottom, or from side to side. The thickness and therefore inabil-
ity of the axe blade to sit deeper into the cut was deemed partly responsible
for this, but it was felt that the major factor was the harder modern brick. This
latter opinion was subsequently confirmed when tested on softer, more tradi-
tional, low-fired rubbing bricks, which the brick axe split accurately in one go,
leaving a reticulated surface that 10-15 seconds on the rubbing stone rubbed
flat to line (Fig. 100).
Nicholson (1823, 389) advocates the use of sand to aid abrasion if the rub-
bing stone is working smooth. Though not unacceptable, dry silver or very
fine loam sand would be necessary to avoid creating a scratched appearance
on the rubbed brick faces. Of particular importance was that the ends of the
bricks, impacting the timber chopping block, in this cutting process, were not
damaged as anticipated, thus allowing them to be squared or bevelled as their
intended use demanded.
A blacksmith subsequently thinned the ends the brick axe blades so it located
more effectively into the grub-saw cut, further improving its effectiveness in
