There are marks on the pages, made by people long, long ago. They trigger electrical discharges in his brain. Not like a seizure, but precise tiny currents. These fluxes form things that cannot exist: a fish breathing air, a wicked witch, snow in the desert. On these little sparks, rising from the bonfire of his mind, he escapes.
Much later he watches a documentary. “They exist,” he cries, “fish with lungs”.
He sells up, and treks the scalding Sahara, searching for snow. Eventually he reaches the white-capped Atlas Mountains and stumbles on to Marrakech, sure he will find the witch.