I followed, thinking that strength would soon fail it.

This happened three times.

On the third occasion it vanished behind a ridge, and, though by now I was out of both temper and patience, I thought I might as well ride to the crest and see if I could get a shot at it on the further side.
I reached the ridge, which was strewn with stones, looked over it, and saw--a Zulu Impi! I rubbed my eyes and looked again.

Yes, there was no doubt of it.

They were halted about a thousand yards away, by the water; some were lying down, some were cooking at fires, others were stalking about with spears and shields in their hands; there might have been two thousand or more of them in all.