Fifteenth and Sixteenth Centuries 85 



Many things present themselves to our eyes which, appearing to be 

 more than natural are considered illusions or works of the devil, although 

 for certain very evident causes and reasons, nature, mother of all things, 

 has produced them; among these is the " feu folet," called " un ardant," 

 which is an exhalation emanating from the earth into the lower regions 

 of the air, where it is ignited by " antiperistase," because in rising it is 

 repelled by the cold of the middle region. . . . 



Of the same kind is the " feu lechant " which licks the mane and 

 hair of animals and the garments of persons, because it is an exhalation 

 diffused from the body, which, coming to meet and strike a similar one 

 in the air, it ignites. Such fires, burning without damage, are perceived 

 the more often in humid, clammy, decaying, marshy and fuming places, 

 as in the neighborhood of kitchens, valleys, cemeteries, under gibbots 

 and where one lets dead bodies decay: because these places exhale fatty 

 fumes thick and viscous, but not warm enough to ascend to the higher 

 regions of the air: but in ascending continuously they [the effluvia] 

 ignite in meeting like fire issuing from two pebbles struck one against 

 the other. 



Wier continued with a discourse on luminous plants, quoting 

 Gesner, and he referred to the glowworm as producing the same 

 kind of light. The word " antiperistasis," used to explain the " feu 

 folet " and the " feu lechant," refers to the meeting of two contrary 

 qualities as a result of which one is intensified. The warm emana- 

 tion of the earth or of an animal body coming in contact with the 

 colder air above actually kindles the two, giving rise to visible light. 

 Many other observations of ignis fatuus and lambens were recorded 

 during the fifteenth and sixteenth centuries but the state of knowl- 

 edge was such that no electrical origin could have been proposed. 



Allied to ignis fatuus in the minds of the people were lights in 

 the heavens. The fifteenth and sixteenth centuries had their regular 

 displays of the aurora borealis. It is interesting to note that Gesner 

 recognized the aurora as a luminescence, and included it in his 

 book on that subject, De Lunariis (1555) . Conrad Lycosthenes 

 (W^olffhart) (1518-1561) has listed many in his Prodigiorum ac 

 Ostentorum Chronicon (Basel, 1557) , a large book profusely illus- 

 trated with woodcuts of double-headed human beings and animals 

 of monstrous and bizarre form. It was translated as The Doome 

 Warning all Men to the Judgements (1581) by S. Batman, Professor 

 in Divinitie. 



The English edition is a remarkable compilation, " Wherein are 

 contayned for the most parte all the straunge Prodigies, hapned in 

 the Worlde with diuers secrete figures of Reuelations tending to 

 mannes stayed conuersion towards God: In manner of a generale 

 Chronicle gathered out of sundrie approued Authors." The wood- 



