She and Allan by H. Rider Haggard

I did not rest as I should that night who somehow was never able to sleep well in the neighbourhood of the Black Kloof. I suppose that Zikali's constant talk about ghosts, with his hints and innuendoes concerning those who were dead, always affected my nerves till, in a subconscious way, I began to believe that such things existed and were hanging about me. Many people are open to the power of suggestion, and I am afraid that I am one of them.

However, the sun which has such strength to kill noxious things, puts an end to ghosts more quickly even than it does to other evil vapours and emanations, and when I woke up to find it shining brilliantly in a pure heaven, I laughed with much heartiness over the whole affair.