She and Allan by H. Rider Haggard

Next day early I left the town of the People of the Axe, having bid a formal farewell to Umslopogaas, saying in a voice that all could hear that as the rivers were still flooded, I proposed to trek to the northern parts of Zululand and trade there until the weather was better. Our private arrangement, however, was that on the night of the next full moon, which happened about four weeks later, we should meet at the eastern foot of a certain great, flat-topped mountain known to both of us, which stands to the north of Zululand but well beyond its borders.

So northward I trekked, slowly to spare my oxen, trading as I went. The details do not matter, but as it happened I met with more luck upon that journey than had come my way for many a long year. Although I worked on credit since nearly all my goods were sold, as owing to my repute I could always do in Zululand, I made some excellent bargains in cattle, and to top up with, bought a large lot of ivory so cheap that really I think it must have been stolen.