Possible Origin of Ignis Fattens. 55 1 



How can the above appearances be explained with reference 

 to the other accounts published concerning the Ignis Fatuus ? 

 — J. Main. Chelsea, September 18. 



Ignis Fatuus. — Your correspondent R. Chambers, F.L.S., 

 having suggested, in his paper on this subject (n. s. page 353.)? 

 the probability that this phenomenon proceeds from the light 

 emitted by certain insects while on the wing, I avail myself 

 of the present opportunity of stating one or two instances 

 that have come within my own observation, which may serve 

 to corroborate the fact mentioned by Mr. Chambers. 



In the days of my boyhood, the Jack-o'-lantern, or Will- 

 with-the-tsoisp, as this phenomenon was more commonly termed 

 in Derbyshire, was, in one particular spot, in the spring of 

 the year, of frequent occurrence. My late father, who fre- 

 quently made observations upon these merry-dancers, and ob- 

 serves, in one of his papers, he was fully convinced that the 

 Ignis Fatuus was nothing more than male glowworms at play, 

 like gnats in the sunbeams. 



In the spring of 1813, I was riding between Sleaford and 

 Lincoln, when a Jack- d -lantern caught my attention, proceed- 

 ing in the same direction as I was travelling. Its motion was 

 irregular, sometimes near the surface of the ground, and then 

 suddenly rising to the height of five or six feet. I followed 

 very cautiously for some distance, being determined, if pos- 

 sible, to obtain a, near view of my luminous guide. As the 

 night was rather dark, I had every thing favourable for ob- 

 servation. At length it rested just at an angle in the road. I 

 dismounted, and proceeded very cautiously, in the hope of 

 capturing it; but in this I was disappointed ; for, on my near 

 approach, whether from the noise I made, or some other cause, 

 it suddenly rose from its resting-place, about two feet from 

 the ground, cleared a high bank, and pursued its course in a 

 direct line over the adjoining fields. The broad and deep dikes 

 rendered pursuit fruitless ; but my eyes followed its almost 

 butterfly motion till the glimmering taper was lost in the 

 distance. I have on one occasion witnessed a very similar 

 flight, if I may so term it, of the Ignis Fatuus in Derbyshire, 

 and near the same spot I have frequently captured female 

 glowworms. 



On my father once being appealed to for the cause of the 

 Jack-o'-lantern, he said it was, he had no doubt, " the male 

 glowworm bearing on amorous wing his joyous partner." 



Whether the Ignis Fatuus is a meteor, or whether it pro- 

 ceeds from luminous insects, is a phenomenon of great interest 

 and worthy of investigation. The following extract from the 

 Kentish Gazette may not be out of place here : — " On Tuesday 



