Cape of Good Hope.

According to Professor Elri Liebenberg : "This map is probably the most important map of the region prepared before the Great Trek commencing ca. 1835. This example of the map is the first update of the landmark map of Southern Africa, first published two years earlier, which provides a cartographic snapshot of settlements and expansion during the early phase of the Great Trek by discontented Boers beyond the Orange River.
It is one of the very few maps to record a very short-lived toponym: "K.GEO Cataract IV 400 ft. high" - the traveller George Thompson was led to the Augrabies Falls by the Koranna people in 1826, his name of King George IV Falls did not take on, but the original Khoi name Aukoerebis, which means ‘place of great noise’, did.
The map records that the Zwart Land, in today’s Western Cape, is ‘very fertile country: it may be considered the Granary of the Cape Colony'. Along the Zeekoei River, a southern tributary of the Orange River, Arrowsmith shows the location of Van Plettenberg’s Beacon (remnants now at the Iziko Museum), the north-east corner of the Cape in the 1770s, but subsequently replaced by the Orange River, as depicted on the map.
The map displays eleven magisterial districts and provides historically important documentation of travel and exploration in South Africa. It shows the routes taken not only by Thompson, who mostly followed well worn tracks, but also those of more pioneering travellers such as Burchell, Cowie and Green & Capt Gardiner, Bain and Biddulph.

This state and subsequent updates of this map provide one of the best cartographic records of the expansion of the Boer settlements to the north and east of the Cape Colony. For example, Arrowsmith indicates on the map, near Phillipolis, then just a missionary station, that this ‘country lately taken possession of by the Colonial farmers because of the protracted drought.’
The map shows the approximate location of indigenous groups, assigning a large area to the ‘Koras or Koranas’, a group that now has been absorbed into the Griqua and other groups. The map shows the tracks of William Burchell who described and drew Kora people and recorded some of their language. Durban is shown in the Colony of Victoria. The Hemel en Aarde or Leper's Institute of which Dr James Barry had been critical.

John Arrowsmith (1790-1873) was from a family of London based cartographers and publishers, and was a founding member of the Royal Geographical Society. His "London Atlas," known for its understated elegance, is considered one of the first truly "modern" atlases of the nineteenth century. John Arrowsmith was a nephew of the patriarch, Aaron, and worked out of London. He was one of the foremost cartographers of the era and, like his uncle, he aspired to design maps that were up to date.

More about J.Arrowsmith [+]

Reference: Tooley pp 18 - 19 in which he details changes since the 1834 edition.