ANIMAL PHOSPHORESCENCE. 453 



The carbon of lighting gas, when the flames are sounding, is certainly almost en- 

 tirely eliminated in fact, it forms upon the interior surface of the sounding-tube 

 at and below the height of the flames a very visible deposit of carbon, which 

 increases while the air of the tube vibrates. I can now afiirm that the pyro- 

 phone is in a condition to act as well with the illuminating gas as with pure 

 hydrogen. The phenomenon of interference is produced exactly in the same 

 condition with the two gases, the same flames occupy the same position in the 

 tube, that is, the third part of the tube's length measured from the base. In addi- 

 tion to the phenomenon of interference, I believe I shall be able to describe a 

 novel process by aid of which the sound produced by burning flames in a tube 

 can be made to cease. 



"Supposing that one or several flames, placed in a tube a third of its height 

 (measured from its base), determine the vibration of the air contained in this 

 tube ; if a hole is pierced at the one-third of the tube, counted from the upper 

 end, the sound ceases. This observation might be applied to the construction of 

 a musical instrument, which wOl be a species of flute, working by singing-flames. 

 Such an instrument, from a musical point of view, will be very imperfect, because 

 the sound will not be so promptly or sharply stopped as when the phenomenon 

 of interference is employed. If, instead of making the hole at the third, it is 

 made at a sixth, the sound will not cease, but it will produce the sharp of the 

 same note. In all these experiments I have clearly detected the formation of 

 ozone while flames cause the air in the tube to vibrate. The presence of this 

 body can, moreover, be ascertained by chemical reagents scientifically known." 

 Given before the Academic des Sciences, December 7, 1874. 



Prof. Tyndall, at a lecture on January 13tl], at the Royal Institu- 

 tion, showed experiments, according to the new principle, with an 

 apparatus of nine flames, which worked during the evening in tubes 

 of different sizes. Journal of the Society of Arts. 







ANIMAL PHOSPHOEESCENCE. 



AMONG the marvels which excite the admiration of the student 

 of Nature, not the least strange is the group of phenomena known 

 under the name of Animal Phosphorescence. We are so accustomed 

 to associate light with heat, and to consider that fire of some kind is 

 necessary to its production, that the imagination is appealed to with 

 unusual force, when we find light proceeding from the body of a living 

 animal Yet, it is well known that the emission of light is not an un- 

 common characteristic among the members of the invertebrate divisions 

 of the animal kingdom. Travelers have often expatiated on the beauty 

 of the scenes which they have witnessed in the tropics, when the seas 

 or forests have seemed to be illimiinated by innumerable sparks of 

 fire; and recent discoveries have shown that the luminous quality- 

 is even more common than was previously supposed. During the 

 dredging expeditions of H. M. S. Porcupine in the years 1869 and 



