354 OBSERVATIONS ON lONIS FATUUS. 



the agitation of the air ceased, I remained stationary and motionless, 

 and observed them again gradually approach. As I could easily 

 reach them, it occurred to me to attempt to light paper by means of 

 them, but for some time I did not succeed in this experiment, which 

 I found was owing to my breathing. I therefore held my face from 

 the flame, and also interposed a piece of cloth as a screen ; on doing 

 which I was able to singe paper, which became brown-coloured, and 

 covered with viscous moisture. I next used a narrow slip of paper, 

 and enjoyed the pleasure of seeing it take fire. The gas was evi- 

 dently inflammable, and not a phosphorescent luminous one, as some 

 have maintained. But how do these lights originate ? After some 

 reflection I resolved to make the experiment of extingviishing them. 

 I followed the flame ; I brought it so far from the marsh, that pro- 

 bably the thread of connexion, if I may so express myself, was 

 broken, and it was extinguished. But scarcely a few minutes had 

 elapsed, when it was again renewed at its source (over the air- 

 bubbles), without my being able to observe any transition from the 

 neighbouring flames, many of which were burning in the valley. I 

 repeated the experiment frequently, and always with success. The 

 dawn approached, and the flames, which to me appeared to approach 

 nearer to the earth, gradually disappeared. 



On the following evening I went to the spot, and kindled a fire 

 on the side of the valley, in order to have an opportunity of trying 

 to inflame the gas. As on the evening before, I first extinguished 

 the flame, and then hastened with a torch to the spot from whence 

 the gas bubbled up, when instantaneously a kind of explosion was 

 heard, and a red light was seen over eight or nine square feet of the 

 surface of the marsh, which diminished to a small blue flame, from 

 two and a half to three feet in height, that continued to burn with an 

 unsteady motion. It was, therefore, no longer doubtful that this 

 ignis fatuus was caused by the evolution of inflammable gas from 

 the marsh. 



In the year 1811, I was at Malapane, in Upper Silesia, and 

 passed several nights in the forest, because ignes fatui were observed 

 there. I succeeded ill extinguishing and inflaming the gas, but 

 could not inflame paper or thin shavings of wood with it. In the 

 course of the same year I repeated my experiments in the Kouski 

 in Poland. The flame was darker coloured than usual, but I was 

 not able to inflame either paper or wood-shavings with it ; on 

 the contrary, their surface became speedily covered with a viscous 

 moisture. 



In the year 1812, I spent half a night in the Rubenzahl Garden, 

 on the ridge of the Riesengobiige, close on the Schneekoppe, which 



