A 'perch' is an antique unit of measure used in stonework, based on the
pole or
rod.
One perch of dry
stone measures 16.5 feet (one rod) by 1.0 foot by 1.5 feet. One perch is equal to 0.70 cubic meters.
See also
★
perch (length) for a related unit of length with the same name.
★
perch (area) for a related unit of area with the same name.