62 On a new Oxide of Hydrogen and its relation to Ozone. 



the tube fg, showed the least change. As the film of phosphoric 

 acid shows even —^ milligrm. of moisture, and at least 4000 

 cub. centims. of oxygen passed through the tube in four hours, 

 it may be regarded as certain that 1 cub. centim. of. the gas 

 could not contain even 10 00 3 00Q milligrms. of moisture. The solu- 

 tion of iodide of potassium in the globe apparatus h not only 

 remained perfectly colourless, but showed no trace of blue on the 

 addition of muriatic acid and solution of starch. Erom this we 

 may come to the conclusion, that electrolytic oxygen gas at a low 

 temperature neither decomposes solution of iodide of potassium, 

 nor bears with it, under the present circumstances, any traces 

 of ozone. 



The experiment was now repeated, with the single difference, 

 that a stream of sparks was passed between the wires fused 

 into the tube /, after any nitrogen, which might possibly have 

 passed into the anterior tube during the removal of the globe 

 apparatus, had been displaced by the stream of oxygen. Even 

 during the first few minutes the solution of iodide of potassium 

 became distinctly yellow, and in the course of an hour 1 milligrm. 

 of free iodine could be shown to exist in it. The film of phos- 

 phoric acid in the spark tube did not exhibit the slightest change 

 during the whole course of the experiment. 



The globe apparatus was now for the third time filled with 

 solution of iodide of potassium, and the removal of any nitrogen 

 effected as before. The experiment was repeated exactly in the 

 same manner, the induction spiral kept in action, but the spark 

 tube exposed to the flame of a small spirit-lamp at i. The solu- 

 tion of iodide of potassium now did not exhibit the slightest 

 yellow colour; and even after the lapse of an hour, no blue 

 colour could be seen on the addition of murk tic acid and solu- 

 tion of starch. After the removal of the iodide of potassium 

 apparatus, the gas streaming from the tube could be readily 

 smelt. By this means not the least trace of ozone was perceptible, 

 but the moment the heating at % was interrupted, the most pene- 

 trating odour of ozone was produced ; this immediately disap- 

 peared on the interruption of the stream of sparks, but again 

 made its appearance on this being re-established. 



The quantity of iodine separated in an hour in the preceding 

 experiment exceeded the quantity of ozone which could possibly 

 result from any contamination with vapour of water more than 

 nine-fold. From this it may be concluded, that there really 

 exists an allotropic oxygen, which at ordinary temperatures is 

 endowed with an affinity which even exceeds that of chlorine. 



The conditions under which this allotropy of oxygen occurs 

 are very remarkable. In the case of almost all other bodies, the 

 allotropy induced by an elevation of temperature is characterized 



