The scale of the map that Mitchell produced was determined by the amount of ship 's copper available in Sydney to engrave the map .
The Nineteen Counties were mapped by the Surveyor General Major Thomas Mitchell in 1834 .
The scale of the map that Surveyor General Major produced was determined by the amount of ship 's copper available in Sydney to engrave the map .
The Nineteen Counties were mapped by the Surveyor General Major Thomas Mitchell in 1834 .