In the June 1926 edition of The South African Philatelist on page 51 under a title An Unchronicled Error the following appeared

One of the old hands in the Union Postal Service, whom we have known for many years and whose word we have no reason to doubt, asked us, in the course of conversation the other day, whether the halfpenny K.E. Transvaal, bi-coloured, was known with the centre inverted. Such a variety not having come to our notice, we asked for further information, where upon an interesting story unfolded. When the bi-coloured halfpenny was current, our informant was on the stamp counter of the Johannesburg G.P.O.
One day, he said, an old Jew with his head closely guarded by a bowler, bought a sheet of halfpenny labels from one of the stamp clerks and departed with his purchase, only to return a few minutes later with the query “Are these all right?”, at the same time passing his sheet across the counter.

The clerk, we were told, noticed that on all the stamps the King’s Head was inverted and replied to the effect that they were not all right, and offered to exchange them for another sheet. The customer, however, insisted on retaining his stamps and departed with them. Our informant states that, before handing the sheet back to its owner, his fellow clerk showed him the sheet, and both he and his mate realised that they were looking at something good. Nothing more has been heard of the stamps, and although the stamp clerks lost no time in examining their stock no further sheets of the variety came to light. A watch was, we were informed, kept on all the halfpenny stamps for years afterwards, without result.

Perhaps some of our readers know something of the above variety. If so, we shall be very glad to hear from them. Incidentally, we may mention that the postal official who unfolded that above story possesses a copy of the fairly well known Transvaal K.E. 2/6 revenue stamp with the inverted centre.

Notes
1. The Edwardian Stamps of the South African Colonies by Brian Trotter page 242
2. Article in the October 2011 edition of The South African Philatelist page 166/67 by Otto Peetoom
3. A Facsimile of a ½d KEVII inverted centre

This fascinating subject was new to most of the audience and focuses on events during the
1899 - 1901 Boer War and Alan’s display includes many interesting items of postal history & memorabilia.
Whenever the Boers retreated they blew up everything of use and badly damaged the railway system. For the British the movement of troops and equipment required the control of the railways. In 1899 four Railway Pioneer Corps were formed with the task of repairing the railways damaged by the enemy.
Often temporary repairs were effected that would bypass the damage and Alan’s display includes photographs that demonstrates the foregoing.
The Railway Corps made use of Postal Stationery and employed their own handstamps on private and official mail.

These handstamps are either encountered as cachets or at times used to cancel postage stamps. They used British or Z.A.R. stamps & stationery and also operated their own T.P.O.’s.
Alan pointed out that when using GB registered envelope the rate was 2d and when they employed Z.A.R. envelopes the rate was 3d. The various T.P.O.s consisted of a Northern T.P.O. that went from Pretoria to Pietersburg and the Western T.P.O. ran to Krugersdorp. The Midland T.P.O. to Bloemfontein and possibly as far South as the major junction of Naauwpoort some 30+ miles South of Colesburg.

Waterval Onder situated 90 metres below the waterfall on the Elands River:
During the Second Anglo-Boer War President Kruger stayed there from July to August 1900 before his departure for Europe.