The arpent did not have the same size everywhere

The arpent was a unit of surface measurement whose value varied considerably from one region to another. This variation came from the fact that the number of perches per arpent fluctuated from 64 to 100 and that the length of the perch itself changed according to the location. In total, this term designated fifty different units, ranging from 30,64 ares to 51,07 ares.