Joseph McCabe, hunter, trader, explorer and plant collector, was the son of an Irish surgeon in the British army. Initially he worked as a clerk in Uitenhage and in 1835 fought in the Sixth Frontier War. Two years later he followed the Great Trek and bought a farm some 20 km north of present Potchefstroom. From there he went on hunting expeditions, but periodically returned to Grahamstown. In 1846 he was accused by the Transvaal authorities of supplying arms and ammunition to local tribes, but the charge was not substantiated. He set out on his first major expedition in 1849, visiting the region north-west of the Limpopo River and collecting information on the route to Lake Ngami from the inhabitants of eastern Botswana. Upon his return to Grahamstown he published information on the route to the lake in the Cape Frontier Times of 12 February 1850. An account of his journey appeared in the issue of 26 February, and in Het Kaapsche Grensblad of 16 February 1850. That same month he and the artist-explorer Thomas Baines* set out on an expedition to Lake Ngami, but they were prevented from travelling beyond Potchefstroom by the Boers who accused McCabe, on the basis of his newspaper articles, of being a British spy. He was fined and sentenced to house arrest on his farm for a year, but managed to escape across the Vaal River in August 1850.
On 1 May 1852 McCabe set out from Bloemfontein on his most important expedition, accompanied by John Maher. Avoiding the Transvaal they pioneered a route across the Kalahari from east to west via Molepolole, Kanye, Sekoma, Kang and Ghanzi. Despite interference by a group of Griquas and living mainly on tsamma melons - for an unprecedented period of 19 days without natural water - they reached Lake Ngami on 28 July. After exploring its surroundings they travelled north-eastwards to the Mababe Depression and then northwards across the Chobe River. On the return journey they met Dr David Livingstone* near present Gaberone, Botswana, in January 1853. McCabe, who had been equipped by Dr W.G. Atherstone* of Grahamstown with a plant press and instructions for preparing botanical specimens, returned to Grahamstown with a small collection of plants - the first such collection from the Ngami and Chobe areas. He also brought back a profitable load of ivory and skins. The plants were handed over to Dr Atherstone, who presented a set to Kew Gardens in March 1856. He kept duplicates, which ended up in the herbaria of the Albany Museum, Grahamstown, and the South African Muskeum, Cape Town. Unfortunately McCabe had lost his notes on the locality of each plant.
McCabe returned to Lake Ngami more than onece. He also travelled to Natal and explored the Drakensberg range northwards to Swaziland. During 1859-1860 he traded in Matabeleland (in present Zimbabwe). He acquired a warehouse in Bloemfontein to store his ivory and trade goods and made the town his headquarters, though from 1861 he also had a store at Molopolole, some 50 km north-west of Gaberone. He died there on his way to his trading post at Lake Ngami in 1865, leaving a considerable fortune to one of his brothers.