Saint Elmos fire

Saint Elmo's fire luminous discharge of electricity extending into the atmosphere from some projecting or elevated object. It is usually observed (often during a snowstorm or a dust storm) as brushlike fiery jets extending from the tips of a ship's mast or spar, a wing, propeller, or other part of an aircraft, a steeple, a mountain top, or even from blades of grass or horns of cattle. Sometimes it plays about the head of a person, causing a tingling sensation. The phenomenon occurs when the atmosphere becomes charged and an electrical potential strong enough to cause a discharge is created between an object and the air around it. The amount of electricity involved is not great enough to be dangerous. The appearance of St. Elmo's fire is regarded as a portent of bad weather. The phenomenon, also known as corposant, was long regarded with superstitious awe.

St Elmo's Fire, the brushlike electric discharge which, under certain atmospheric conditions, takes place at the mastheads and yardarms of a ship. It is known by over 50 different names, including St Ermyn, St Telme, St Helm, St Ermo, St Anselmo, etc., and was sometimes described by British seamen as ‘Jack with a lantern’. The name is believed by some to be a corruption of St Erasmus, a patron saint of Mediterranean sailors. But it has also been equated with St Peter Gonzales (c.1190–1246), a Dominican friar who, after crusading with Ferdinand III of Spain against the Moors, devoted much of his life to improving the conditions of seafaring people along the Spanish coasts. One of the earliest recorded uses of it appears in a vow invoking the aid of Pope Urban V (1362–70) which caused ‘the light of St Elemi’ to appear. In the Middle Ages the appearance of the phenomenon was greeted sometimes with joy, sometimes with dread, and it was the origin of a number of superstitions held by seamen, some benevolent, some not. Italian mariners of the 15th and 16th centuries believed that the lights emanated from the body of Christ and gave them the name of Corposanto, of which again there are many derivatives. It is also occasionally seen on aircraft flying among thunderclouds and sometimes on shore on prominent points such as church spires.