270 EXPERIMENTAL INVESTIGATIONS. 



Experiment 13. Oxygen and chlorine. Very considerable 

 action on the iodide at first, but not constant; it abated within 

 the first hour, and after twenty-four hours the action was 

 extremely feeble, scarcely perceptible: the water had risen 

 nearly to the top of the chlorine tubes, but the level in the 

 oxygen tubes was unaltered. The chlorine was negative to 

 oxygen, or, in other words, the oxygen was in its voltaic 

 bearing to chlorine as hydrogen to oxygen. 



As in this experiment the water-level in the oxygen tubes 

 was unaltered, it appeared that this gas had little to do with 

 the action ; I therefore, in 



Experiment 14, charged the alternate tubes of a battery 

 with chlorine and dilute sulphuric acid ; the amount of action 

 was much the same as in experiment 1 3, and equally transi- 

 tory ; a few gaseous bubbles were perceptible on the platinums 

 in the oxygen cells, but not in sufficient quantity for exami- 

 nation. It is well known that chlorine of itself will slightly 

 decompose water, forming hydrochloric acid, and evolving 

 oxygen, and there is little doubt that the voltaic action here 

 observed was due to this. There was no appearance of the 

 platinum having been attacked in several experiments which 

 I made with chlorine. So slight a chemical action will, how- 

 ever, give rise to voltaic effects, that the absence of any ap- 

 parent corrosion is not conclusive. It is stated by chemists 

 that gaseous chlorine will not attack platinum, but that it is 

 only when nascent it combines with this metal ; non constat, 

 however, that in the gas battery the chlorine at the initiatory 

 instant of its electro-synthesis may not be in a state analogous, 

 as to its chemical energies, to that converse state called 

 nascent, and therefore we cannot venture to negative the 

 possibility of the platinum being slightly attacked. This 

 circumstance, added to its extreme solubility and power 

 of decomposing water, makes chlorine rather an unsatisfac- 

 tory element for the class of actions developed by the gas 

 battery. 



Solutions of bromine, chlorine, and iodine have been before 

 experimented on (I believe by Dr. Schcenbein and M. Bec- 

 querel) as to their voltaic relations, but in examining the vol- 

 taic relations of bodies in a gaseous state, or, to express myself 



