The Black Tome of Alsophocus (fiction)

"The Black Tome of Alsophocus" is a short story by H.P. Lovecraft and Martin S. Warnes. It appears in the collection New Tales of the Cthulhu Mythos (1980 and 1989).

It tells the story of a human who discovers a spellbook called the Black Tome of Alsophocus, described as "that legendary manuscript written centuries ago by the great necromancer Alsophocus, who lived in the land of Erongill before ever modern man ever had taken his first uncertain steps upon the earth". The narrator learns much sorcery from the Black Tome and eventually travels with his mind to Sharnoth where Nyarlathotep dwells.