84 
as far as tlie water or dirt had touched them, all in a kind of faint 
dame, much like that, as he described it, of burnt brandy, which 
continued upon them for a mile’s riding.*.” 
The foregoing account exactly agrees wdth a curious history of 
the same phenomenon, contained in the collection of manuscript 
communications to the Royal Society, in the library of the British 
Museum. It is entitled, “ A Relation of a Fiery Appearance in the 
Impress of Men’s and Horses’ Feet,” and was given in these words, 
by Dr. Croon, about the year 1665 : 
“ Being Monday, on my return with Sir John Courton, Bart, and 
his clerk, William Stephens, from the Lord Bishop’s Visitation at 
Launceston, about an hour, in a misty dewy night, on Hinxon, 
about a mile beyond Kellington, in Devonshire, in Launceston 
road, in a moorish place of some forty feet in length, the impress of 
our horses and our own feet upon the ground, appeared fiery, much 
more shining than glow-worms ; the grass we gathered in those 
places where we or our horses trod, reserved the lustre in our hands 
when we came to the waters within a quarter of a mile from Kel- 
lington ; where watering our horses, we observed it, but almost 
extinguished, only a spark here and there. At Newton, two miles 
thence, we viewed it by candle-light that night, as also the next day, 
and found it coarse spiry grass, of an inch, or a little more, in length, 
such as ordinarily grows on downsf .” 
That this phenomenon, as well as that of the Ignis fatuns, depends 
on some peculiar modification of phosphorus, there seems to be no 
difficulty of admitting. Nor can there exist any doubt, as to the 
source whence volatile alkali, and even the phosphorus itself, is 
derived, when it is recollected, that with this crust of mould, a con- 
siderable quantity of animal matter must be blended, proceeding 
* The Natural History of Staffordshire, by Dr. Plott, p. 115. 
f Mr. Ayscough's Catalogue, 698, p. 47. 
