392 EXPERIMENTAL INVESTIGATIONS. 



excess of hydrogen is less ; and probably if the exact point of 

 the solution were attained, there would be no excess. 



3rd. When the solution is much stronger than that which 

 makes the best electrolyte, there is a notable excess of oxygen. 



4th. When the electrodes exceed a certain size, water con- 

 ducts without any apparent signs of decomposition. 



On making a search for any previous experiments on this 

 subject, I find that Faraday ('Phil. Trans.' 1834, p. 91) has 

 observed that when a strong solution of sulphuric acid, formed 

 by mixing two measures of oil of vitriol with one of water, was 

 subjected to ordinary electrolysis, a remarkable disappearance 

 of oxygen took place. The strength of the acid he then em- 

 ployed would be very nearly that employed by me in experi- 

 ment 7 ; but in my experiment, when the solution is subjected 

 to decomposition by the spark from the secondary coil, ex- 

 actly the converse effect takes place, and there is a notable 

 disappearance of hydrogen. 



Faraday attributes the disappearance of the oxygen to 

 the formation of peroxide of hydrogen ; but in those of my 

 experiments where oxygen disappeared, this could hardly be 

 the case, as the gases are eliminated at a point of ignition at 

 which this compound would be decomposed, and in many of 

 my experiments the liquid was kept very nearly at the 

 boiling-point. 



I abstain at present from expressing any opinion as to the 

 cause of these singular anomalies, and hope to make a farther 

 communication on the subject, when I can resume and com- 

 plete some experiments which I have in view, but which it 

 will be some time before I can undertake. 



THE ELECTRICITY OF THE BLOWPIPE FLAME. 



Phil. Mag., January 1854. 



VOLTA and Erman made known the first indications of the 

 production of electricity by flame. Pouillet and Becquerel 

 have experimented and reasoned on the statical effects of such 

 electricity, while Andrews, and more recently Hankel and 



