Tine Ghealáin (direct translation is a ‘flash of fire’) and commonly known is English as Will-o’-the-Wisp. In folklore, a will-o’-the-wisp, will-o’-wisp or ignis fatuus (Latin for ‘giddy flame’), is an atmospheric ghost light seen by travelers at night, especially over bogs, swamps or marshes. It is known in European folklore by a variety of names, including jack-o’-lantern, friar’s lantern, hinkypunk and hobby lantern and is said to mislead travelers by resembling a flickering lamp or lantern.
In Ireland the term Tine Ghealáin can also be translated to ‘Summer lightening’.
The Will-o’-the-Wisp looks like a bright green flame that is normally surrounded by a dense white mist. It also has a scientific explanation and is said to be due to the gases given off of decomposing animals and plant matter. Decomposing any organic matter in damp and wet areas goes through a process known as “aerobic decomposition”. This is different to the decomposition process that happens in say a compost pile. In bogs and marshes aerobic decomposition is restricted and in the absence of air, the matter is broken down by anaerobic bacteria. Decomposition that is withcout oxygen creates gases such as methane, carbon dioxide, nitrogen, and phosphines. Phosphines are highly flammable and when exposed to air can sponteneously burst into flames. Giving off a bright green glowing light.
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