326 EXPERIMENTAL INVESTIGATIONS. 



num intensely ignited will decompose water, and several 

 considerations press on the mind in reflecting on this novel 

 phenomenon. 



First of all, to those who are attached to the cui bono argu- 

 ment, and estimate physical science in proportion only to its 

 practical applications, I would say that these experiments 

 afford some promise of our being, at no distant period, able to 

 produce mixed gases for purposes of illumination, &c., by 

 simply boiling water and passing it through highly ignited 

 platinum tubes, or by other methods which may be devised ; 

 we in fact by this means, as it were, boil water into gas, and 

 there appears theoretically no more simple way of producing 

 chemical decomposition. 



To pass however to more important considerations : the 

 spheroidal state, which has lately attracted the attention of 

 philosophers, appears to be closely connected with these 

 results, and is rendered more deeply interesting. The last 

 experiment but two which I have mentioned shows that the 

 spheroidal state is intermediate between ordinary ebullition and 

 the decomposing ebullition. It is probably therefore a state 

 of polar tension, co-ordinate in some respects with that which 

 takes place in the cell of a voltaic combination before decom- 

 position, or when the power employed not being of sufficient 

 intensity to produce actual decomposition, the state commonly 

 called polarisation of the electrodes, obtains. The phenome- 

 non brings out also a new relation between heat, electricity, 

 and chemical affinity ; hitherto many electrical phenomena 

 could be produced by heat and chemical action, the difference 

 being that in the effects produced by the last two forces there 

 was no polar chain, but every minute portion of the matter 

 acted on gave rise to the phenomena which in the electrical 

 effects are only observable at the polar extremities ; thus in 

 decomposing water by iron and sulphuric acid, or by passing 

 steam over heated tubes of iron, parallel results are obtained 

 to the electrolysis of water with an iron anode ; but in the 

 former cases every portion of the iron oxidated gives off its 

 equivalent of hydrogen ; in the latter the equivalent is evolved 

 from the cathode at a point distant from that v/here the oxi- 

 dation takes place. Hitherto electricity has been the only 



