544 Intelligence and Miscellaneous Articles. 



by the strong cohesion of individual atoms. But as ordinary oxygen 

 is gaseous, the liypothesis in question must also assume that each 

 separate molecule acts repulsively upon similar molecules. It might 

 therefore reasonably be asked, why do the oxygen molecules repel 

 each other, while the atoms constituting such molecules mutually 

 attract ? When 10, 100, 1000 atoms of oxygen unite together form- 

 ing one molecule, why does not each such number of atoms combine 

 to form a larger solid body .? Why is the oxygen gaseous ? 



2. Ozone remains unaltered in the cold ; by heat it is converted 

 into ordinary oxygen, in which condition it remains after cooling. 

 M. de la Rive must therefore explain this change by assuming that 

 oxygen, consisting of separate atoms (ozone), again assumes a mole- 

 cular state when its temperature is raised ; in fact, that heat faci- 

 litates the cohesion of the oxygen atoms, an action the opposite of 

 that which is generally ascribed to this agent. 



3. Ozone possesses smell, while ordinary oxygen does not; the 

 former is a violent poison, the latter an indispensably necessary sup- 

 porter of animal existence. That these great differences in the phy- 

 siological action of oxygen and ozone should be owing merely to a 

 different state of mechanical aggregation of the elementary atoms, 

 appears to me very difficult to imagine. 



4. It is known that by chemical union with certain bodies oxygen 

 acquires the same oxidizing pro])erties as it acquires when free 

 under the influence of electricity or contact with phosphorus. For 

 example, when one equivalent of nitric oxide (NO") combines with 

 two equivalents of oxygen gas, the latter enter into a condition of 

 chemical activity precisely similar to that which ozone possesses. 

 It would be difficult to explain how passive oxygen had in this case 

 been converted into action, according to the liypothesis of M. de la 

 Rive. Probaljly we must assume that NO" breaks up the molecules 

 of ordinary oxygen gas, entering into combination with it, and con- 

 verts it into the ozonized or atomic condition. 



Some years since, Mr. Hunt put forward an hypothesis as to the 

 nature of ozone, which is precisely the opposite to that of De la Rive ; 

 according to it the ordinary oxygen was in an atomic, and ozone in a 

 molecular condition. Hunt brought forward no facts of any kind in 

 support of his hypothesis, and I remarked at the time that tlie op- 

 posite view might be entertained with equal justice, and I still con- 

 sider both hypotheses of equal value. So long as we are unac- 

 quainted with ozone in a puie state, and especially do not know 

 positively anything of its state of aggregation, specific gravity, &c., 

 it appears advisable to postpone all theorizing on the subject, and 

 especially the advancing of hypotheses which are themselves based 

 only upon hypotheses, such, for example, as that which assumes the 

 existence of atoms. With regard to my own opinions, I do not 

 venture to hazard the most remote conjecture as to the cause of that 

 difference in the properties of ordinary oxygen and ozone, differ- 

 ences which are quite as mysterious as remarkable. I will, how- 

 ever, state that it has never yet entered into my mind to seek this 



