Page:Popular Science Monthly Volume 84.djvu/321

Rh Ozone is a form of oxygen in which three, instead of the usual two, atoms are united in the molecule. It is present in minute quantity in the atmosphere, usually not of cities, but of the country and the sea. Its powerful oxidizing properties and its intemperate advocacy by enthusiastic but unscientific persons have caused it to be hailed popularly as highly beneficial to the human body, not only in ordinary respiration, but in the purification of the air of living rooms, the destruction of bacteria and other organic matters, and the cure of disease. On crisp cool mornings we are fain to enlarge our chests as we step into the open, and breathe in deep draughts of this supposedly health-giving gas; to mountain tops and forests we go in search of its renovating properties; and our mail is fat with circulars descriptive of the marvelous benefits of ozone machines, of ozonizers and ozonators. In many offices and homes we find these machines, busily at work discharging into the atmosphere their peculiarly odoriferous product. Very recent investigations, however, seem to make it clear that the supposed beneficial powers of ozone as a home companion are creations of the imagination. Two groups of American investigators, Jordan and Carlson in Chicago and Sawyer, Beckwith and Skolfield, in Berkeley, have independently carried out each a series of careful experiments on the action of ozone on bacteria, animals and human beings. They find that ozone will indeed kill bacteria exposed in a room, but only when in such concentration that it will kill guinea-pigs first.

When present in any considerable quantity in the air ozone is irritating and probably corrosive to the lining membrane of the air passages of the nose, throat and lungs, causing the blood-vessels of this membrane to be excessively dilated and to present the customary symptoms of "sore throat." It causes headache and drowsiness. The heart, at first accelerated, is later slowed and weakened, and the pressure of the blood in the arteries is unduly lowered. The case for ozone thus seems to narrow down to a supposed beneficial action in destroying or modifying unpleasant odors in the air of a room. When in not too great concentration such odors are, it is true, overcome, though it is quite probable that their disappearance is due, not to an actual destruction of the odoriferous substance, but partly to a replacement of the disagreeable odor by the odor of ozone and partly to fatigue or anesthesia of the olfactory membrane of the nose. It is very questionable whether this is wise, and Jordan and Carlson well say: