The Will-o’-the-wisp is a ghost light seen by travelers at night, especially over bogs, swamps, or marshes. The phenomenon in English folk belief is also referred to as the Friar’s Lantern or hinkypunk. The light is said to mislead travelers and are associated with fairies.

The stories of Will-o’-the-wisps can be traced in written record to the early 19th century though they were in the oral lexicon much earlier than that. In A Dictionary of Fairies, author K.M. Briggs notes that these fairies can be observed primarily in graveyards and bogs and calls them “ghost candles.”

The will-o’-the-wisp can be found in folktales around the world including Britain, the Americas, and even China. These phantom lights appear in marsh environments luring people into danger. In some stories, the lights even represent good and evil.

So what are these strange lights?

Historians believe that will-o’-the-wisps are etiological folk tales or a myth used to describe the natural world. Several theories exist as to the cause of the phantom lights. One of the most commonly accepted theories was discovered by Allesandro Volta in 1776 with his discovery of methane.

Volta proposed that electricity in the air mixed with swamp gas causing the ghost lights. At the time of his proposal, it was considered extremally controversial. It was disregarded because of the unlikeliness of spontaneous combustion and people saw the lights retreat when approached.

Today, scientists can prove Volta’s theory more or less accurate. Will-o’-the-Wisps are caused when organic matter breaks down in persistently wet areas – such as bogs or swamps. The movement of the wisps can be explained by the dispersal of the gas by the air currents.

As the gases from the break down of organic material rise and escape into the atmosphere, the methane mixes with phosphines and creates the blue lights seen hovering over the swamp. These phosphines are flammable and can burst into flame in the presence of oxygen. This produces the dense blue and white cloud that people describe as the Will-o’-the-wisps.

All of the stories of these phantom lights are explained as something supernatural. However, even back in the 18th century, there were explanations based in scientific theory for these ghostly lights.

Sources:

Geller, Sans’, .tdb-post-meta{margin-bottom:16px;color:#444;font-family:’O., Geller, P., By, & Geller, P. (2017, January 19). Will-o’-the-Wisp – Ghost Light at night. Mythology.net. Retrieved October 22, 2022, from https://mythology.net/mythical-creatures/will-o-the-wisp/

Surfandsunshine. (2022, September 6). The legend behind the will o the wisp in brave. Surf and Sunshine. Retrieved October 22, 2022, from https://www.surfandsunshine.com/will-o-the-wisp-brave/

Upton, E. (2013, April 20). What causes will-o’-the-wisps. Today I Found Out. Retrieved October 22, 2022, from http://www.todayifoundout.com/index.php/2013/04/what-causes-will-o-the-wisps/