The Rev. John Brand (1744-1806) was an antiquarian and folklorist whose main publication was Observations on Popular Antiquities: Including the Whole of Mr. Bourne's Antiquitates Vulgares (1777). The following essay is a transcription from an 1888 edition of that work, edited, corrected, and updated by W. Carew Hazlitt.
Of The Phenomenon Vulgarly Called Will or Kitty With a Wisp, or Jack with a Lanthorn.*
* To these titles may be added that of "Kit with the Canstick" (i.e., candlestick), as it is called by Reginald Scot. Wisp here implies a little twist of straw, a kind of straw torch. Thus Junius in verbo: "Frisiis 'wispien,' etiamnum est ardentes straminis fasciculus in altum tollere." these names have undoubtedly been derived from its appearance as if Will, Jack, or Kit, some country fellows, were going about with lighted straw torches in their hands.
"A wand'ring fire
Compact of unctuous Vapour, which the Night
Condenses, and the Cold environs round,
Kindled through Agitation to a flame,
Which oft, they say, some Evil Spirit attends,
Hovering and blazing with delusive Light,
Misleads th' amaz'd Night-Wand'rer from his way
To bogs and mires, and oft through Pond or Pool,
There swallow'd up and lost, from succour far."
MILTON."How Will a' Wisp misleads night-faring Clowns,
O'er Hills, and sinking Bogs, and pathless Downs."
GAY.This appearance, in Latin designated Ignis fatuus, has long formed an item in the catalogue of popular superstitions. Clowns, however, are not the only persons who have been misled by it, for as the subsequent account of it will evince, it has hitherto eluded the most diligent pursuit of our writers of natural history. The phenomenon is said to be seen chiefly on summer nights frequenting meadows, marshes, and other moist places. It is also often found flying along rivers and hedges, as if there it met with a stream of air to direct it. It is called Ignis fatuus (or foolish fire), according to Blount, "because it only feareth fools;" whence came the proverbial phrase "An ignis fatuus has done it," to signify that a man has been led away by some idle fancy or conceit. The expression in The Tempest, "played the Jack with us," is explained by Johnson to mean "He has played Jack with a lanthorn; has has led us about like an Ignis fatuus, by which travellers are decoyed into the mire." Anciently it was called Elf-fire, as in the title-page of a curious tract (1625), "Ignis Fatuus, or the Elf-fire of Purgatorie;" and the Warwickshire phrase Mab-led (pronounced Mod-led) signified led astray by a will-o'-the-wisp. It also had the title of Gyl burnt Tayle, or Gillion a burnt Taile, as in Gayton's Festivous Notes upon Don Quixote; and it was besides called a Sylham Lamp, as we read in Gough's edition of Camden: "In the low grounds at Sylham, just by Wingfield in Suffolk, are the Ignes Fatui, commnoly called Sylham Lamps, the terror and destruction of travellers and even of the inhabitants, who are frequently misled by them." Reginald Scot has the word "Sylens" before he mentions "Kit with the Can-stick," which doubtless is a corruption of the word Sylham. In a tract of the date of 1648, entitled A Personal Treaty with his Majesty and the two Honourable Houses, the alternative designations are "some Ignis Fatuus, or a Fire-Drake, some William with a Wispe, or some Glow-worme illumination;" and in the Vow-breaker (1636) we read of "Ghosts, Hobgoblins, Will with a Wispe, or Dicke a Tuesday."
Blount defines it to be a certain viscous substance reflecting light in the dark, which is evaporated out of a fat earth and flies in the air. "It commonly haunts churchyards, privies, and fens, because it is begotten out of fatness: it flies about rivers, hedges, &c., because in those places there is a certain flux of air. It follows one that follows it, because the air does so."
One of the popular attributes of the Ignis fatuus, as we have already seen, is the love of mischief in leading men astray in dark nights, which in Drayton's Nymphydia is given to the Fairy Puck—
"Of purpose to deceive us:
And leading us makes us to stray
Long Winter Nights out of the way,
And when we stick in mire or clay,
He doth with Laughter leave us."Hentzner, in his Travels in England in the year 1598, relates that on the return journey from Canterbury to Dover "there were a great many Jack-w'-a-Lanthorns, so that we were quite seized with horror and amazement."
The author of The Comical Pilgrim's Pilgrimage into Ireland (1723) writes: "An Ignis fatuus the silly people deem to be a Soul broke out of Purgatory;" and in A Wonderful History of all the Storms, Hurricanes, Earthquakes, &c. &c., and Lights that lead people out of their way in the Night (1704), we are told of these "Lights usually seen in Churchyards and moorish places," that in supersitious times the Popish clergy persuaded the ignorant people "that they were Souls come out of Purgatory all in flame, to move the people to pray for their entire deliverance; by which the gulled them of much money to say Mass for them, every one thinking it might be the Soul of his or her deceased Relations."
In the account of the surprising preservation and happy deliverance of the three women buried thirty-seven days in the ruins of a stable, by a heavy fall of snow from the mountains, at the village of Bergemoletto in Italy, 1755, by Ignazio Somis, physician to his Sardinian Majesty, it is stated that when the unhappy prisoners "seemed for the first time to perceive some Glimpse of Light, the appearance of it scared Anne and Margaret to the last degree, as they took it for a Forerunner of Death, and thought it was occasioned by the dead Bodies; for it is a common Opinion with the peasants that those wandering Wild-Fires which one frequently sees in the open Country are a sure presage of Death to the persons constantly attended by them, which ever way they turn themselves, and they accordingly call them Death-Fires."
The Ignis fatuus, however, apparently is not confined to the land, sailors often meeting with it at sea. They regard the appearance as ominous, and if in stormy weather a single one is seen flitting about the masts, yards, or sails, it is thought to indicate certain shipwreck; but if there are two of them, the crew hail them with shouts of joy, and augur from them that a calm will very shortly ensue.
Burton in his Anatomy (1632) says that "the Spirits of Fire in form of Fire-Drakes and Blazing-Stars sit on Ship Masts," &c. Hence the passage in the Tempest—
"On the Top Masts,
The Yards, and Bowspirits, would I flame distinctly."We find the subsequent passage in Hakluyt's Voyages, 1598: "I do remember that in the great and boysterous Storme of this foule Weather, in the Night there came upon the top of our Maine Yard and Maine Mast a certaine little Light, much like unto the light of a little Candle, which the Spaniards call the Cuerpo Santo. This Light continued aboord our Ship about three houres, flying from Maste to Maste, and from Top to Top; and sometimes it would be in two or three places at once."
In the Scottish Encyclopaedia, v. LIGHTS, we read: "Dr Shaw tels us that in thick hazy weather he has observed those luminous Appearances which at Sea skip about the Masts and Yards of Ships, and which the Sailors call Corpusanse, which is a corruption of the Spanish Cuerpo Santo;" and, under METEOR: "Pliny, in his Second Book of Natural History, calls these appearances Stars, and tell us that they settled not only upon the Masts and other parts of Ships, but also upon Men's Heads. Two of these Lights forebode good Weather and a prosperous Voyage; and drive away the single one, which wears a threatening aspect. This the Sailors call Helen, but the two they call Castor and Pollux, and invoke them as Gods. These Lights do sometmies about the evening rest on Men's Heads, and are a great and good Omen. These Appearances are called by the French and Spaniards inhabiting the Coasts of the Mediterranean St Helmes or St Telmes Fires; and by the Italians the Fires of St Peter and St Nicholas."*
* In Cotgrave we read: "Feu d'Helene, Feu S. Herme, St Helen's or St Herme's Fire; a meteor that often appears at sea: looke Furole." "Furole, a little Blaze of Fire appearing by Night on the tops of Souldiers Lances, or at Sea on the Sayle Yards, where it whirles and leapes in a moment from one place to another. Some Mariners call it St Hermes Fire; if it come double, 'tis held a signe of good lucke, if single otherwise."
Among the apothegms at the end of Herbert's Remains (1652) is the following: "After a great Fight there came to the Camp of Gonsalvo, the great Captain, a Gentleman produly horsed and armed; Diego de Mendoza asked the great Captain, who's this? who answered, 'Tis St Ermyn that never appears but after a Storm;" and Thomas Heyrick's Submarine Voyage (1691) has—
"For lo! a suddain Storm did rend the Air:
The sullen Heaven, curling in frowns its brow,
Did dire presaging Omens show:
Ill-boding Helena ALONE was there."The question as to the origin of "a vapor which by Mariners is called a Corpo Zanto usually accompanying a Storm," is answered in the British Apollo (1710) thus—
"A. Whenever this Meteor is seen, it is an Argument that the Tempest which is accompanied was caused by a sulphureous Spirit, rarifying and violently moving the Clouds. For the cause of the Fire is a sulphureous and bituminous matter, driven downwards by the impetious motion of the Air and kindled by much agitation. Sometimes there are several of these seen in the same Tempest, wandering about in various motions, as other Ignes fatui do, tho' sometimes they appear to rest upon the Sails or Masts of the Ship: but for the most part they leap upwards and downwards wihtout any Intermission, making a Flame like the faint burning of a Candle. If five of them are seen near together, they are called by the Portuguese Cora de nostra Senhora, and are looked upon as a sure sign that the Storm is almost over."
In Dickenson's Greene in Conceipt (1598) we read—
"As when a wave-bruis'd Barke, long tost by the Windes in a Tempest,
Straies on a forraine Coast, in danger still to be swallow'd
After a World of Feares, with a winter of horrible objects—
The Shipman's solace, faier Ledas twinnes at an instant
Signes of a Calme are seen, and, seene, are shrilly saluted."Wright's MS. has the following also: "Hoc certum satis, cum ejusmodi faculae ardentes olim insidissent super capita Castoris & Pollucis ad Expeditionem Argonauticam, exinde Dioscuri in Deos indigites relati, et tanquam solida & sola Maris numina ab omnibus Navigantibus summa in veneratione habiti, cumque procellis suborientibus Tempestas immineat, astraque illa ab olim ominosa Antennis incubent, Castorem et Pollucem in auxilium adesse nemo dubitat." Hence, adds Gregory, through the supersititon of ancient sailors the signs of Castor and Pollux were placed on the prows of ships.
So, in A Wonderful History of all the Storms, Hurricanes, Earthquakes, &c. (1704), occurs an account "of Fiery Impressions that appear mostly at Sea, called by Mariners Castor and Pollux. When thin clammy Vapours, arising from the Salt Water and ugly slime, hover over the Sea, they, by the motion in the winds and hot blasts, are often fired, these Impressions will oftentimes cleave to the Masts and Ropes of Ships, by reason of their clamminess and glutinous substance, and the Mariners by experience find that when but one flame appears it is the forerunner of a storm; but when two are seen near together, they betoken fair weather and good lucke in a voyage. The naturall cause why these may foretell fair or foul weather is, that one flame alone may forewarn a Tempest, forasmuch as the matter being joyn'd and not dissolved, so it si like that the matter of the Tempest, which never wanteth, and Wind and Clouds, is still together, and not dissipate, so it is likely a Storm is engend'ring; but two flames appearing together denote that the exhalation is divided, which is very thick, and so the thick matter of the Tempest is dissolved and scattered abroad, by the same cause that the flame is divided: therefore no violent Storm can ensue, but rather a calme is promised."
A species of this phenomenon, known in Buckinghamshire by the name of "the Wat," is said also to haunt prisons; on the night previous to the arrival of the judges at the assizes making its appearance like a little flame, and being accounted a most fatal omen by every felon to whom it becomes visible; insomuch that the moment the unhappy wretch sees it, he reckons his case hopeless, and resigns himself to the gallows.
The theory of some is that the Ignis fatuus arises from a viscous exhalation which, kindled in the air, reflects a sort of thin flame in the dark without any sensible heat.
As an example of the explanations that were accepted as satisfactory in the early part of the seventeenth century, we may here submit an extract from A Help to Discourse (1633)—
"Q. What Fire is that that sometimes followes and sometimes flyeth away?
A. An Ignis fatuus, or a walking Fire (one whereof keepes his station this time near Windsor), hte pace of which is caused principally by the motion of the Ayre enforcing it."
In the event of this not being considered as very satisfactory, perhaps the following from Curiosities, or the Cabinet of Nature (1637), will suffice—
"Q. What is the cause of the Ignis fatuus, that either goes before or follows a Man in the Night?
A. It is caused of a great and well compacted Exhalation, and, being kindled, it stands in the Aire, and by the Man's motion the Ayre is moved, and the Fire by the Ayre, and so goes before or follows a Man: and these kind of Fires of Meteors are bred near execution places, or Church Yards, or great Kitchens, where viscous and slimy matters and vapours abound in great quantity."
Willsford writes in his Nature's Secrets (1658): "The lowest Meteor in the Air is the burning Candle, or, as some call it, Ignis fatuus. This is a hot and moist vapour which, striving to ascend, is repulsed by the Cold, and, fired by Antiperistasis, moves close by the Earth, carried along with the vapours that feed it, keeping in low or moist places. The Light is of an exceeding pale colour, very unwholesome to meet withal by reason of the evil vapours it attracts unto it, which nourishes the pallide flame and will often ascent (as those Exhalations do) and as suddainly fall again, frmo whence the name is derived." He adds: "These pallid Fires appear but at some times of the Year, and that in certain places; and in those parts where they are most usual, they are not commonly seen, but as forerunners of sultry heat in Sommer, and wet in the Winter: they are usually observed to appear in open Weather."
Sir Isaac Newton characterises it as a vapour shining without heat, and pronounces that there is the same difference between this vapour and flame as between rotten wood shining without heat, and burning coals of fire. On the other hand, some have supposed the Ignis fatuus to be nothing more than some nocturnal flying insect; and in favour of this hypothesis we are informed that the Ignes fatui five proof, as it were, of sense by avoiding objects; they they often go in a direction contrary to the wind; that they often seem extinct, and then shine again; and that their passing along a few feet above the ground or surface of the water agrees with the motion of some insect in quest of prey, as does also their settling on a sudden, as well as their rising again immediately. Some indeed have affirmed that Ignes fatui are never seen but in salt marshes, or other boggy places; it is proved, however, they they have been seen flying over fields, heaths, and other dry places.
The appearance commonly called a Falling Star (or, more properly, "a Fallen Star") has by a late writer been referred to the half-digested food of the winter gull, or some other bird of that kind. Dr Charlton's description of this in his Paradoxes has perhaps the quaintest thought on it that can be found in any language. "It is," says he, "the Excrement blown from the Nostrils of some Rheumatic Planet falling upon plains and sheep pastures, of an obscure red or brown Tawney; in consistence like a Jelly, and so trembling if touched," &c. Widely difference are the sentiments of Pennant, who affirms that the gelatinous substance known by the name of star-shot, or star jelly, owes its origin to the winter gull; being nothing but the half-digested remains of earthworms, on which these birds feed, and which they often discharge from their stomachs.
In White's Peripateticall Institutions in the way of that eminent person and excellent philosopher Sir Kenelm Digby (1656) the subject is treated thus: "Amongst ourselves, when any such matter is found in the Fields, the very Countrey-men cry it fell from Heav'n and the Starres, and, as I remember, call it the Spittle of the Starres." He adds: "An Ignis fatuus has been found fallen down in a slippery viscous substance full of white spots," and he defines Ignes fatui (or Wills-o'-the-wisp) to be "a certain viscous substance, reflecting light in the dark, evaporated out of a fat Earth and flying in the Aire. They commonly haunt Churchyards, Privies, and Fens; because they are begotten out of fatnesse. They follow one that flies them, and fly one that follows them; because the Aire does so. They stay upon military Ensigns and Spears; because such are apt to stop and tenacious of them. In the Summer and hot regions they are more frequent; because the good Concoction produces fatnesse."
In the Statistical Account of Scotland (1797), under the head of the parish of Bendothey in Perthshire we read: "The substance called Shot Stars is nothing else than frosted Potatoes. A Night of hard Frost in the end of Autumn, in which those Meteors called falling Stars are seen, reduces the Potatoe to the consistence of a Jelly, or soft Pulp, having no resemblance to a Potatoe, except when parts of the skin of the Potatoe adhere below undissolved. This pulp remains soft and fluid when all things else in Nature are consolidated by Frost; for which reason it is greedily taken up by Crows and other Fowls, when no other sustenance is to be had, so that it is often found by Man in the actual circumstance of having fallen from above, having its parts scattered and dispersed by the fall according to the law of falling bodies. This has given rise to the Name and vulgar Opinion concerning it."
Merian's Account of the famous Indian Lanthorn Fly represents that it has a hood or bladder on its head, which gives a light like a lanthorn in the night, but by daylight is clear and transparent, curiously adorned with stripes of red or green colour; and that writing of tolerably large character may be read by the light of it at night. It is said that the creature can either dilate or contract the hood or bladder over its head at pleasure, and that, when captured, it hides all its light, which is affords plentifully only when at liberty.
We gather from Boreman's Description of a great variety of Animals and Vegetables that a respectable person in Hertfordshire, presuming upon his familiarity with the grounds about his house, was tempted one dark night to follow one of these Ignes fatui which he saw flying over a piece of fallow ground; when it led him over a ploughed field, flying and twisting about from place to place—sometimes suddenly disappearing, and as suddenly reappearing. Once it made directly for a hedge, on nearing which it mounted over; and he lost sight of it after a full hour's chase. On his return home he saw it again, but he was too fatigused to think of renewing the pursuit.
At astley, seven miles from Worcester, three gentlemen saw one of these appearances in a garden about nine o'clock on a dark night. At first they imagined it to be some country-fellow with a lanthorn, until, after approaching within about six yards, it suddenly disappeared. It became visible again in a dry field, thirty or forty yards off. It disappeared as suddently a second time, and was seen again a hundred yards off. Whether it passed over the hedge, or went through it, could not be observed, for it disappeared as it passed from field to field. At another time, when one approached within ten or twelve yards, it seemed to pack off as in a fright.
Hutchinson's History of Cumberland relates of a lake at Barfield in the parish of Whitbeck: "Here, and in the adjoining Morasses, is much of that inflammable Air which forms the lucid Vapour vulgarly called Will with the Wisp, frequently seen in the Summer Evenings."
The Ignis fatuus is reported to have been observed to stand still as well as to move, and sometimes to have been apparently fixed on the surface of the water. In Italy they profess to have discovered two varieties, one on the mountains, and the other on the plains; and these are called Cularsi by the common people, who regard them as birds, of which the belly and other parts are resplendent like the pyraustae or fireflies. Naturalists, as we have already observed, are greatly divided in opinion on the subject; one inclining to consider the Ignis fatuus as no more than an aggregation of small luminous insects; Ray looking upon it as simply the effulgence of some nocturnal insect; and Derham pronouncing it to be composed of fixed vapours; while the Scottish Encyclopaedia defines it to be a kind of light, supposed to be of an electric nature, that appears frequently in mines and marshy places, and in the vicinity of stagnant waters. The last authority adds: "It was formerly thought, and is still by the superstitious belived, to have something ominous in its nature, and to presage death and other misfortunes." There have been instances of people being decoyed by these Lights into marshy places, where they have perished; whence the names of Ignis fatuus, Will with a Wisp, and Jack with a Lanthorn, as if this appearance was an Evil Spirit, which took delight in doing mischief of that kind."
The apparitions of light or fire upon the manes of horses and men's hair (in Latin, flammae lambentes) are called, we know not why, HAGGS; which, blount explains, "are said to be made of sweat or some other vapour issuing out of the head; a not unusual sight among us when we ride by night in summer time. They are extinguished, like flames, by shaking the horses' manes; but I believe rather it is only a vapour reflecting light, but fat and sturdy, compacted about the manes of horses or men's hair."
From Hyll's Contemplation of Mysteries (of the date of Elizabeth) we take the following passages—
"Of the Fire cleaving and hanging on the Partes of Men and Beastes. This Impression for troth is prodigious without any phisicke cause expressing the same when as the Flame or Fire compasseth about anye person's heade. And this straunge wonder and sight doth signifie the royal Assaultes of mightie Monarchies, and Kinges, the Governementes of the Emperie, and other matters worthie memory, of which the Phisicke Causes sufficient can not be demonstrated. Seeing, then, such fyers or lightes are, as they wer, counterfets or figures of matters to come, it sufficiently appeareth that those not rashely do appeare or showe but by God's holy will and pleasure sent, that they maye signifie some rare matter to Men. This Light doth Virgill write of in the seconde Booke on Aeneados, of Ascanius: which had a like flame burning without harme, on his heade. Also Livius in his first Book, and Valerius Maximus reporte of Tullius Servius, a childe, who, sleeping on bedde, such a Flame appeared on his heade and burned rounde aboute the heade without harme, to the wonder of the beholders: which sight pronounced after his ripe age, the comming unto royall Estate."
Again—
"What is to be thought of the Flame of Fyre, which cleaveth to the Heares of the Heade and to the Heares of Beastes.
Experience witnesseth that the Fyre do cleave manye times to the Heads and Eares of Beastes, and often times also to the heades and shoulders of Men ryding and going on foote. For the Exhalations dispearsed by the Ayre cleave to the heares of Horses, and Garments of Men: which of the lightnesse doe so ascende, and by the heate kindled. Also this is often caused when Men and other Beastes by a vehement and swift motion wax very hote, that the Sweate, fattie and clammye, is sent forth, which kindled yeldeth this forme.
and the like maner in all places, (as afore uttered,) as eyther in moyst and clammie places, and Marishes, in Churchyards, Cloysters, Kitchins, under Galosses, Valleys, and other places, where many deade Bodies are laide, doe such burning Lightes often appeare. The reason is, that in these places the Earth continually breatheth forth fatte fumes, grosse and clammy, which come forth of dead Bodyes: and, when the fume doth thus continually issue forth, then is the same kindled by the labouring heate, or by the smiting togither: even as out of two Flint Stones smitten togither fyre is gotten.
To conclude, it appeareth that such Fyres are seene in moyst Kitchins, Sinckes, or Guttours, and where the Orfall of Beastes killed are throwne: or in such places most commonly are woont to be seense. Such fires cleaving doe marveylously amase the fearfull. Yet not all fires which are seene in the Night are perfite Fiers: in that many have a kinde without a substaunce and heate, as those which are the Delusions of the Devill, well knowne to be the Prince of the World, and flyeth about in the Ayre."
So in A wonderful History of all the Storms, Hurricanes, Earthquakes, &c. (1704) we read: "These are sometimes clammy exhalations scattered in the air in small parts, which in the Night, by the resistance of the cold, are kindled, by cleaving to Horses' ears and Men's heads and shoulders, riding or walking; and that they cleave to Hair or Garments it is by the same reason the Dew Cleaves to them, they being dry and attractive, and so more proper to receive them. Another kind of these Flames are when the bodies of Men and Beasts are chafed and heated, they send forth a fat clammy Sweat, which in like manner kindles, as is seen by sparkles of Fire that fly about when a black Horse is very hard curryed in the dark, or as the blue Fire on the Shells of Oysters, caused by the nitrous Salt. Livy reports of Severus Tullius that, sleeping when a Child, his Hair seemed to be all on a flame, yet it did him no harm: he also tells us of one Marius, a Knight of Rome, who as he was making an Oration to his Soldiers in Spain, which such vehemency as heated him, his head appeared to them all in a flame, though himself was not aware of it."
From the subsequent description by Blount it would seem that the appearance of the Fire-drake is distinct frmo that of the Ignis fatuus: "There is a Fire sometimes seen flying in the Night, like a Dragon: it is called a Fire-Drake. Common people think it a Spirit that keeps some treasure hid, but Philosophers affirm it to be a great unequal exhalation inflamed between two Clouds, the one hot, the other cold (which is the reason that it also smokes), the middle part whereof, according to the proportion of the hot Cloud, being greater than the rest, makes it seem like a belly, and both ends like a head and tail."*
* White in his Peripateticall Institutions calls the Fiery Dragon "a weaker kind of Lightning. Its livid colour, and its falling without noise and slowly, demonstrate a great mixture of watery exhalation in it. 'Tis sufficient for its shape, that is has some resemblance of a Dragon, not the expresse figure."
Fire-drake, according to Steevens, is the name both of a serpent, anciently called a brenning-drake or dipsas, and of a Will-o'-the-wisp, or Ignis fatuus; as in Drayton's Nymphidia—
"By the hissing of the Snake
The rustling of the Fire-Drake;"and in Chapman's tragegy of Caesar and Pompey (1607)—
"So have I seene a Fire-Drake glide along
Before a dying Man, to point his Grave,
And in it stick and hide."Again, in Glapthorne's Albertus Wallenstein (1640)—
"Your wild irregular lust which, like those Fire-Drakes
Misguiding nighted travellers, will lead you
Froth from the fair path," &c.—Brand, Rev. John (1777), Observations on Popular Antiquities: Including the Whole of Mr. Bourne's Antiquitates Vulgares.
Since I transcribed this article, I've been referring to it quite often. The primary feature that I mention is the fact that Brand speaks of St. Elmo's Fire as though it's a form of the Will-o'-the-wisp, which is good proof that the category "Will-o'-the-wisp" has been conflated with other phenomena in the past, as Devereux has already shown (Earth Lights Revelation, p.18, the Charles Leeson Prince quote). It may also point to further desynonymisation that may occur in the category. As I wrote in April 2006:
I don't doubt that some from of gaseous emission by the earth that gets ignited through some convoluted mechanism may account for the bulk of what we call Will-o'-the-wisp sightings. Or it may be some other mechanism, but in the broad sense I would say there is likely to be a core of sightings that share a similar mechanism. But then the more mobile sightings—the sightings of lights that dance about and reappar elsewhere, or move against the wind—may have a completely different explanation. They may be more akin to earth lights, for all we know, or something different entirely.
Secondly, the point that Brand makes about "fat" and offal is very interesting: it may be that this has contributed more to the process than has heretofore been suspected in the 20th century. In other words, we tend to concentrate on the direct mechanism producing the lights, e.g. with the phosphene theory, but we don't seek to explain how the methane that powers the reaction is produced in the first place in abundance.
Thirdly I have quoted that wonderful passage of Dr. Charlton on pwdre ser: "It is the Excrement blown from the Nostrils of some Rheumatic Planet falling upon plains and sheep pastures". Brand is certainly right to call the quote "perhaps the quaintest thought on it that can be found in any language".
Sean B. Palmer