ON OZONE IN RELATION TO HEALTH AND DISEASE. 39 
not be all true, — but because they fall short of perfect demon- 
stration. We must yield that Ozone in excess, as we produce 
it in the laboratory, induces certain symptoms of disease ; but 
as yet we know of no instance in which an excess sufficient to 
produce the same symptoms exists in nature. An air so 
charged with Ozone as to produce these symptoms, would 
require no chemical test to prove the presence of an injurious 
agent. It would be an irrespirable air, and it would affect 
with varying intensity all who breathed it. In order, there- 
fore, to sustain these conjectures in their entirety, we must 
assume two positions, each of which is yet unproven : firstly, 
that Ozone may exist in intensity in the air, although not 
detectable by the present recognized tests or by the senses ; 
and, secondly, that there are local currents of Ozone which 
cross the path of one person and injure him, while others 
■escape. Both these positions are possible, but they are not 
proven. They will be approached by steady work at oxygen, 
-a body which we once thought the immortal Priestley had 
divined and defined, but regarding the nature of which we 
stand as yet like little children, who, thinking they detect 
form and colour and beauty in a soap-bubble, suddenly are 
perplexed by seeing it resolve itself into the, to them, invisible 
and unknown. 
Reader, I fear you are weary, and I too tire. I have only 
one or two things more to say on the text I have taken, and 
<{ cito ” shall be the motto. Firstly, then, let me add in 
regard to active oxygen. Ozone, that as it is the great purifier 
■of the dead earth, so perchance it is the physical purificator 
•of the living animal. The light shines doubtfully here, but 
the direction of it is to show that when oxygen gas is brought 
into contact with the blood in the living lungs, it is in part 
transformed into Ozone, and that the subtle, active agent is 
doing its work more secretly but not less certainly, within the 
tissues of the organism, than in the world without. Secondly, 
I would mention that the special physiological effects of 
Ozone are destroyed by heat, and are obscured or prevented 
by extreme cold. In experiments to show the effects of Ozone 
on animal respiration, a temperature not lower than 65 deg. 
Fahr., and not higher than 75 deg., should be sustained. 
Thirdly, I would state that there is a condition of atmo- 
spheric oxygen in which that gas exhibits an opposite condition 
to the ozonised state. Oxygen in this opposite or negative con- 
dition is called antozone. There are different methods of pro- 
ducing antozone which I have not space to describe; but I must 
note that in some experiments on the re-inhalation of air many 
times over I was able to reduce oxygen to such negative state 
that it failed to support life. The act of purifying such oxygen 
from carbonic acid and other tangible impurities had no effect 
