Corpse candles--canwll corfe in the original Old Welsh--are synonymous with jack o' lanterns and will o' the wisp. They represent death.
Death in fifth century Europe tended to be sudden. David, patron saint of Wales, prayed for warning; a subsequent vision told him that death would be prefaced by small lights, like those from tapers.
I remember that for some years after my grandfather died my grandmother insisted that the white streak that ran down his last photo was a feather, as in wing. (It was the camera's strap, of course). We need corpse candles.
Science vs. Need
Corpse candles are prolific in Welsh folklore as small lights that float
along near the ground, stopping at houses where death is forthcoming.
But it has variations, like any legend. It follows the path of a future
funeral procession; it appears to a doomed party
halfway between his home and his grave. A small light signifies the
death of an infant and a large light signifies the death of an adult. Color is also significant: red for man, pale blue for woman,
pale yellow for child.
While their significance is hearsay, their presence is real. Near
waters in the South of Wales, one sees lights at night, like candles.
Phosphorescence is not an obscure phenomenon. Things in nature produce light. I drive between mountains long after sunset; lightning bugs answer my headlights. Gases --particularly those ejected as a by-product of swampiness--combine, and at night they glow. Run electric current
through glass tubes containing elemental ether, such as helium, or nitrogen, and you get light of the purest red and blue you'll ever see.
Mixed correctly, natural gases glow, and regardless of anything people die. Thus, patterns.
There are countless stories of death prefaced by mysterious lights. One, provided by William Howell:
In passing Golden Grove from Llandilo to Carmarthen,
several people in the eighteenth century saw three corpse-candles
gliding down the river at various times three weeks in succession. The
persons compared their experiences, and wondered what the omen meant.
Was it for the villagers, or was it for the noble family who lived at
Golden Grove? At length the solution came. Three members of the
nobleman's family died simultaneously in different parts of the country.
There are also stories of corpse candles appearing in rooms, in houses, far
away from swamps. Author V. Wales reproduces the following
account, crediting only a "Mr. Price":
In the year 1880 his brother, a native of Carmarthenshire
and captain of a vessel, was away at sea. When at home, he occupied a
small room only suitable for one person. One evening, about six o'clock,
a dim light was seen in that room by a cousin from a neighbouring farm.
The young man asked "Is Jack
come home?" "No" was the reply. "Then who is in the room?" he asked,
and the answer was that "nobody had been there with a candle." The
circumstance passed unnoticed, until another member of the family, and
an inmate of the house, saw a dim glimmer, "like a rushlight or taper"
through the window. Later still the mother one night, going into the
room to pull down the blind, turned to go to the door, and over the bed
saw a dim hovering light. She went downstairs in considerable agitation,
and exclaimed to the members of her family the hope that nothing had
befallen Jack. The mail was eagerly waited for, and in the meantime
neighbours saw the dim light in Jack's room. A few weeks later news
reached the family that the captain died at Singapore of fever about the
time the corpse-candle appeared in his room. 2
Dig a bit, and you find stories again and again of corpse candles
appearing away from natural phenomena--inside bedrooms, over deathbeds.
But, as is their way, these things become fantastic and apocryphal at the same rate. We read messages in light because death makes us desperate.
Of course, corpse candles are only one entry in a very large volume of Things That Make Precious Sense of Death.
If you're looking to conduct more research on corpse candles and all its cousins/variants, you'd be interested in the following:
"Corpse Candle" is also a book by Paul Doherty.
1 Howell, William. "Cambrian Superstitions," 60-61.
2What can only be assumed to be a verbal eyewitness account. Reproduced at "Corpse candles and Phantom Funerals" — http://www.red4.co.uk/Folklore/trevelyan/welshfolklore/chapt14/htm
The Encyclopedia of Ghosts and Spirits
V Wales, "Corpse Candles and Phantom Funerals."
For another good story involving corpse candles, see Mary Thomas' "A Man from Ysbyty Ystwyth sees a Corpse Candle": http://walespast.com/en/folktales/stories/?id=15