Hendrik J. Wikar, son of a Swedish surveyor, grew up in Göteborg, Sweden. He was employed by the Dutch East India Company in Amsterdam and sent to the Cape as a soldier in 1773. For two years he worked as a clerk in the company's hospital in Cape Town, but in April 1775 deserted because of a gambling debt. With a rifle and two horses he fled into the interior, at first eastwards as far as the Sundays River, then beyond the settled region of the Kamiesberg, where he remained for more than four years. Nothing is known about his movements until September 1778, when the surviving account of his travels starts at Goodhouse, along the Orange River. Travelling upstream with a group of Khoi and a group of San he left the river at Beenbreek and joined it again at Augrabies Falls early in October. He was the first European to visit and describe he falls. The party turned back at the point where the kraals of the Korannas began. Wikar described the customs of his companions and of tribes they met along the way, and mentioned many plants and animals, particularly those used as food. The plants and minerals he collected on this journey were lost in a fire.
On 1 April 1779 he sent a letter to Governor J.A. van Plettenberg, requesting pardon for his desertion. He mentioned that he had made a collection of natural curiosities and had kept a journal with notes on the customs of the Khoi, including three then unknown tribes. These were the Einicquas, living on islands in the Orange River; the present Korannas; and the Briqua (Ba-Thlaping) of Bantu origin. While waiting for an answer he set out on a second journey along the Orange River, again travelling upstream, this time as far Koegas, about half-way between the present towns of Groblershoop and Prieska. On this journey he again collected plants, minerals, Khoi utensils, some elephant tusks, and the skins of mammals, birds and reptiles. By early June he was back along the lower reaches of the Orange River. Upon receiving his pardon he travelled to the colony and on 25 July 1779 at the Kamiesberg met Colonel R.J. Gordon*, who was on his way north with W. Paterson*. Wikar was reinstated in the Dutch East India Company's service in September 1779. Unfortunately his collection has vanished.
His report on his wanderings, requested by Governor van Plettenberg, was based on his journal and was written by Landdros O.G. de Wet. A shorter version, with some additions, was prepared for Hendrik Cloete, heemraad of Stellenbosch. Wikar also compiled a sketch map of his routes, but he had no surveying skills or compass. His report is valuable for the information it contains about the geography, natural products and people with whom he came into contact. Most important is his first-hand account of the initiation rites, ceremonies and customs of the Khoi with whom he lived. His ethnographic information was discussed, among others, by Dr H. Vedder in Das alte Südwestafrika (1934).