190 Prof. Bischof on the Inflammahle Gases of 



night at the deepest part of the bore ; which thus had sufli- 

 cient time to acquii-e the temperature of the spot. Next 

 morning, on drawing it rapidly up to the surface, the tempe- 

 rature was 72° R. (194° F.). Watery vapour issued from the 

 bore ; but there was no empyreumatic smell perceptible. Mr 

 Sello has given me hopes that he will cause a second bore to 

 be made on the hanging side, in order to reach the highly in- 

 clined stratum, so far as it may still be burning at a greater 

 depth. I must say, that the above-mentioned negative facts 

 lead me to suppose that this second bore also will encounter no 

 l)urning stratum ; but, at all events, it is of great interest to 

 attain certainty on the subject. 



During my two visits to the burning mountain, I neglected 

 to make a simple experiment which would have determined 

 decisively if the bed is still in a state of ignition, viz, to ascer- 

 tain if the gases which issue from the fissures of the slate- 

 clay are inflammable or not. In order to supply this omis- 

 sion, I lately begged my former pupil, Dr .Jordan of Saarbriick, 

 to make the experiment. This gentleman, who is a zealous 

 and successful cultivator of the natural sciences, most kindly 

 acceded to my request, and has communicated the following 

 result : — ■" I have carried on my investigations with the greatest 

 care in all the considerable fi.ssures of the burning mountain, 

 and have employed a Davy lamp, an ordinary mining light, 

 and a wax taper. There has been in no instance an inflam- 

 mation of the air, in no instance an enlargement of the flame, 

 anil in no instance an explosion. The light was soon extin- 

 guished, most speedily in the western fissures, v»hich are lined 

 with crystals of sulphur, and from which sulphurous acid and 

 watery vapour issued.'" 



After this result, one can hardly believe here in a really 

 burning bed. Whence, then, comes the considerable heat 

 which presents itself over a great extent .^ Towards the east, 

 at a distance of 800 feet from the edge of the basin in which 

 are the numerous fumaroles, I found at a depth of one foot 

 a temperature of 14^ (63°. 5 F.) ; while, away from the burning- 

 mountain, the temperature of the ground was' 12^ (59- F.). 

 At many places nearer the basin, the temperature was from 



