110 Explosion of Hydrog€7i and Oxygen. 



where the compression would be about thirty atmospheres, no 

 such effect was produced. And in the present case^ the conden- 

 sation had been made rapidly, and two hours before the explosion 

 occurred. It is not impossible that the state of compression and 

 close approximation of the particles of the gases may have aided 

 the rapid combination, and but a slight increase of temperature 

 have been required to produce explosion^ which may have been 

 caused in the tube, by the slight explosions to which I have be- 

 fore alluded as so often occurring in the jet. The capacity of 

 the jet and stop cock, in front of the safety tube, was sufficient 

 to contain but about one cubic inch of the gases, and the com- 

 bustion of so small a quantity could have had but little influ- 

 ence in raising the temperature of the safety tube ; probably 

 none, when we consider that the compressed gases were expand- 

 ing as they passed out, and no doubt attended with the usual 

 effect, the absorption of caloric. 



In a letter now before me. Dr. Hare has suggested the heat- 

 ing effect of the previous slight explosions, as the most probable 

 cause of the final explosion ; but for the reasons just stated, I am 

 constrained to seek for some more satisfactory explanation. 



Although it would be difficult, if not impossible, to prove that 

 electricity, from the presence of the different metals entering 

 into the construction of the various parts of the apparatus, or de- 

 veloped by, or evolved from the gases, or the products of their 

 first partial combustions, was not the immediate cause of this 

 explosion, it would be equally difficult, in the present state ot 

 our knowledge, to prove that it was. The ignition of platinum 

 sponge, and the combination of oxygen and hydrogen which it 

 effects, it is well known, were, when first observed, attributed by 

 Dobereiner to electricity, which has not been disproved, or satis- 

 factorily explained, even by the researches of Faraday. 



Having communicated to the distinguished inventor of the 

 compound blow-pipe a brief notice of the occurrence which 1 

 have described, it will not, I trust, be deemed an undue hberty 

 to remark, that in the letter above referred to, Dr. Hare appears 

 to consider all explosions as dependent on "a mysterious electrical 

 reversal of polarities," and that we are not as yet able to deter- 

 mine all the modes by which such reversals may be induced. 



From the first experiments made with the Hemming's tube, 

 it is obvious that it cannot be said that the wires were not of 



