1873 double rate envelope to ROSS with a 4d cancelled by a CHRISTCHURCH SE 17 73 duplex canceller with a barred ‘C’. Hokitika and Ross SE 22 73 transit and arrival backstamps. Ross was a very small gold mining town on the west coast of the South Island, 15 miles from Hokitika. The mails were carried either by the local storekeeper / mail clerk or policeman on horseback between the two township’s. From Christchurch to Hokitika and return the mail travelled via the Arthurs Pass, the Otira mail coach taking two days for the journey. which explains why the 170 mile trip took 5 days. An uncommon double rate item, and a very late use of this 4d stamp.