In September 1519, Ferdinand Magellan set off from Spain in attempts to circle the globe.
His ships made their way to the Cape Verde Islands in the first few weeks. From there,
they sailed south into uncharted waters. Uneasy, the crew began to fear when violent
storms struck. They threatened to mutiny if Magellan did not turn back. Suddenly, the
tops of the masts were enveloped with bubbles of flickering, bluish light. In maritime
lore, it was St. Elmo’s fire, a manifestation of the patron saint of sailors. Observers
claim the holy body of St. Elmo himself appeared many times in the light. The phenomenon
stayed for two hours or more. Sailors cried for mercy as the light began to disappear,
and at that moment the sea grew calm.
Later investigation has shown that the light was simply a discharge of electrical
voltage that had built up in the vessels in response to low-laying, electrically charged
clouds. The masts, which were tall and pointed objects, provided the easiest avenue for
electricity to pass into the air, where it excited gas molecules, causing them to glow.
The belief that St. Elmo’s fire is beneficial is actually quite dangerous, since the
atmospheric conditions that accompany it increases the likelihood of lightning strikes.
In fact, St. Elmo’s fire helped cause the explosion of the Hindenburg on May 6, 1937.
The captain delayed the landing of the hydrogen-filled balloon to give a thunderstorm
time to abate. When the rain decreased to a drizzle, the ship began its descent and crew
members threw heavy ropes to the ground. Immediately, however, bright flames appeared
around the craft’s tail and spread to engulf the ship. Some jumped to safety, but
thirty-six perished.
Investigators found that leaking hydrogen had been ignited by an electrical current that
moved upward from the ground along the balloon’s landing ropes. The usually innocuous St.
Elmo’s fire sparked a fire that destroyed the airship and stopped the future of
dirigible transportation.