1818.] On the Sounds produced by Flame in Tubes. 25 



as to afford a candle-flame that may be introduced into the 

 tube ; light it, and introduce it about 5 or 6 inches, and a clear 

 musical tone will be obtained. 



During the experiments that were made in consequence of 

 this view of the subject, many appearances occurred which 

 might be added to the above account, to support the opinion 

 that the vibration of the flame, in consequence of rapid suc- 

 cessive explosions, is the cause of the sound ; but they are 

 neglected, because they are supposed unnecessary. 



If the explanation given be true, then the only requisite to 

 the production of these sounds is the successive sudden in- 

 flammation of portions of gaseous explosive mixtures. These 

 mixtures are most easily made by propelling a stream of air on 

 to a stream of inflammable gaseous matter ; but it is also pos- 

 sible to make them in other ways, and the same phenomenon 

 may be produced in a different manner. 



That the tube is not essentially necessary, is shown by making 

 it swell out into a cylinder of 3 or 4 inches diameter, except 

 above and below ; or part of it may be extended into a globe. 

 I took two air-jars that were open above, but with contracted 

 apertures ; one of these was inverted over an inflamed jet of 

 hydrogen, so as to form a lamp or bell-glass about it : there 

 was no effect of sound, because the downward currents from 

 above interfered with the stream of air issuing up from be- 

 neath, and made it irregular ; but placing the second receiver 

 on the first, applying them edge to edge, so as to preserve the 

 current of air upwards from disturbing forces, the sounds were 

 immediately produced ; and lastly, I succeeded in obtaining 

 the tones by the draught of a common chimney ; for, by attach- 

 ing a large inverted air-jar to the end of a funnel-pipe that 

 came from the flue, closing the other lower opening into it, and 

 introducing an inflamed jet of hydrogen within the lower con- 

 tracted orifice of the glass, the sounds were produced. 



That the same sounds may be obtained by means different 

 to those above described, though depending on the same cause, 

 is shown by some experiments made by Sir H. Davy, in his 

 first researches on the miners' safety-lamp. Small wire-gauze 

 safety-lamps being introduced into air-jars filled with explosive 

 atmospheres, the gases burnt on the inside of the cylinder, and 



