CHEMICAL SCIENCE. 189 



gen can now be detected. Cholera cases go on increasing as the 

 poisonous substances accumulate. As the barometer decreases slowly, 

 the south current slowly advances ; but that it is advancing is shown 

 by the cirri, the higher strata of the air. The air becomes more moist, 

 because the moist current is approaching. The south or ozoniferous 

 current at last gains the ascendency, and cholera vanishes, because 

 the incompletely oxidized bodies, the poisonous substances, perhaps 

 hydrocarbons, are rendered innocuous by the ozonized air affording 

 them oxygen. These views are supported by the facts that diarrhoea 

 and choleraic diarrhoea are most common in the autumn months, and 

 then ozone is at its minimum, and that ozone is invariably absent 

 during cholera periods. Cholera is also observed to advance from east 

 to west ; so do the polar current and the calm. I may state also, in 

 support of these views, that during the cholera epidemic at Newcastle, 

 in 1853, the calm prevailed, and ozone was at its minimum. From 

 the 24th of August to the llth of September, 1854, ozone was only 

 once perceived, and then in a minimum quantity. Cholera was then 

 at its height in London. On the 10th of September I wrote to a 

 friend, stating that the south or ozoniferous current was approach- 

 ing, and requested him to watch its effects upon the epidemic. On 

 the llth we had a south wind, with ozone, and from that day the 

 number of cases of cholera diminished. In conclusion, I have to 

 observe, that in making ozone observations the test-paper ought to 

 be kept in the dark ; that sulphuretted hydrogen, ammonia, and 

 moisture, cause the loss of color. 



INFLUENCE OF OZONE OX ORGANIC SUBSTANCES. 

 The following valuable contribution to our knowledge of the nature 



^J CJ 



and action of ozone has been published, during the past year, by 

 Mr. T. K. Hornridge, M. D., F. R. C. S., of London. It wil^be read, 

 we think, with special interest by all interested in medical science. 



The discovery by Schonbein of that peculiar condition of oxygen, 

 named by him ozone, and its great differences from ordinary oxygen, 

 all referable to its more energetic oxidizing power, have, for the last 

 few years, attracted considerable notice among experimental physi- 

 ologists, especially in Germany. It was natural to expect that a 

 substance, capable of acting with energy on various inorganic sub- 

 stances, would be found to possess a similar power over some, at least, 

 of the constituents of the animal frame ; and there are, indeed, some 

 phenomena observable in their mutual reactions, which have given 

 rise to the suggestion that ozone may play a great part in the pro- 

 duction of the unceasing changes in the animal body. 



For a complete elucidation of the subject, it will be necessary for 

 me to prelude my observations with a brief notice of the leading 

 characteristics of ozone, its sources, and its nature. Its great source 

 is unquestionably electricity, whether frictional or dynamic. Hence 

 its presence in abundance in the air after a thunder-storm, in the 

 oxygen generated by the electro-decomposition of water, in oxygen 

 exposed for a time to a bright sunshine, in the air over an evaporating 

 surface, and in the oxygen given off from plants by respiration. 

 Now, this origin of ozone from electricity gave, probably, the first clue 



