Tristan da Cunha taxed item

A post office was first opened on the South Atlantic island of Tristan da Cunha on 1 January 1952. Between 1908 and 1952 there were no postal arrangements for Tristan da Cunha. It has been stated that:

For all practical purposes, prior to 1952 the islanders had neither money nor stamps, and letters were therefore almost invariably posted without stamps, and hence they were taxed at double the foreign letter rate on delivery.

This cover was posted on Tristan da Cunha, date unknown. It arrived in Cape Town on 8 March 1937, where it received the Cape Town Paquebot cancellation. The letter also received the 1d. surcharge in Cape Town, indicating 1d postage due. From Cape Town it was sent to its destination in Pretoria, where it received the UNPAID UNBETAAL cachet. When the unpaid item was collected by the addressee, and the 1d postage due paid, the cover was franked with the 1d postage due and duly cancelled with the PRETORIA 11 MAR 37 postmark.