St Elmo's fire

St. Elmo's Fire is an electro-luminescent discharge caused by ionisation of the air during thunderstorms. It takes the form of a bluish-white glow that projects, often in double or triple jets, from tall, sharply-pointed structures such as masts, spires and chimneys. Although referred to as "fire," St. Elmo's Fire is in fact a kind of plasma caused by a massive atmospheric potential difference. It is not the same phenomenon as ball lightning, although it is related.

St. Elmo's Fire was so-named because the phenomenon commonly occurs at the mastheads of ships during thunderstorms at sea, and St. Elmo[?] is the patron saint of mariners.

References to St. Elmo's Fire, often know as "corposants" or "corpusants" from the Spanish "Corpos Santos" (Saint's Body), can be found in the works of Julius Ceaser, Pliny and Herman Melville.

"'Look aloft!' cried Starbuck. 'The corpusants! The corpusants!' All the yard-arms were tipped with a pallid fire; and touched at each tri-pointed lightning-rod-end with three tapering white flames, each of the three tall masts were silently burning in the sulphurous air, like three gigantic wax tapers before an altar."

Herman Melville, Moby Dick.