In 1818, the Edo area was officially specified on a map with a red line (called shu-biki), and at the same time, the area to be controlled by the machi-bugyo was shown with a black line (called sumi-biki).
1818年には江戸の範囲が地図上に赤い線（朱引）で正式に定められたが、同時に町奉行の管轄する範囲も黒い線（墨引）で示された。