the Chemical Combination of Plain and Ozonized Oxygen. 107 



nary oxygen as not to occupy any volume of their own ; whilst 

 Von Babo and others think an exactly opposite disposition of 

 the atoms is the true one. 



The interest that attaches itself to ozone, both from its pecu- 

 liar actions and the extraordinary constitution it must possess, 

 as shown by the researches of Andrews and Tait, make it most 

 desirable that more should be known about it. I have endea- 

 voured to do something towards fixing a knowledge of its consti- 

 tution. I have tried to find which opinion, Clausius's or Von 

 Babo's, is the correct one ; that is, whether ozone is composed of 

 combined or isolated atoms. 



The manner in which I have endeavoured to solve the pro- 

 blem is founded on the principle I proved in this Magazine in 

 October 1851, and now universally admitted, viz. that the de- 

 composition of compounds absorbs heat. I thought that, sup- 

 posing ozone to differ from oxygen in the arrangement of its 

 atoms, less heat should be produced by it than by oxygen from 

 union with another body if the atoms were in a combined state, 

 because a certain amount of the heat of combination would be 

 absorbed by the decomposition or disuniting of the compound 

 molecule, — and that an opposite result might be expected from a 

 different arrangement. I therefore determined to cause both 

 ordinary and active oxygen to unite with a like body under 

 similar circumstances, to find which, if either, produced the 

 greater amount of heat. I accordingly mixed a measured quan- 

 tity of ozonized air over water with a known volume of deut- 

 oxide of nitrogen; and with the same quantity of ordinary 

 air I mixed a like volume of the deutoxide as in the first experi- 

 ment, and markedthe rise of temperature with a thermometer in 

 both instances. I took every possible precaution to ensure uni- 

 formity of circumstance in the two series of trials, and I repeated 

 them frequently, but I found that no difference in the rise of 

 temperature produced was apparent. The increase of tempera- 

 ture in both amounted to 9° F. 



The ozonized air was obtained by putting a mixture of sulphuric 

 acid and permanganate of potash, according to Bottger's plan, 

 under an inverted funnel, the narrow end of which entered a bottle, 

 so as to keep any ozonized air that was produced. After twelve 

 hours the starch- and iodide-of-potassium papers were turned 

 blue. I made ozone also by leaving phosphorus partly covered 

 with water in a large bottle. I could not, however, compare the 

 air thus ozonized with common air, because the former contained 

 a variable quantity of oxygen. After twenty-four hours' partial 

 immersion of the phosphorus in water nearly all the oxygen was 

 removed, having formed phosphoric acid; the quantity that 

 remained was not known, and therefore could not be compared 

 with ordinary air. 



