400 Intelligence and Miscellaneous Articles, 



bines chemically with chlorine, bromine and iodine when water is 

 present, and chloric, bromic and iodic acids are formed. Strongly 

 ozonized atmospheric air, when exposed to lime-water, produces ap- 

 preciable quantities of nitrate of lime. It may be stated, generally, 

 that nascent ozone, when in contact with nitrogen and a strong base, 

 produces nitric acid ; a small quantity of nitric acid is also formed 

 during the slow combustion of phosphorus in the air. Ozone acts 

 powerfully on most metals, causing them to assume their maximum 

 of oxidizement ; the action commences at 32°. It combines directly 

 with olefiant gas without decomjiosition ; it destroys sulphuretted 

 and seleniuretted hydrogen, &c., and converts sulphurous and nitrous 

 acids, &c. into sulphuric and nitric acids. 



Ozone precipitates peroxide of lead from an alkaline solution of 

 lead, or from tlie acetate. It rapidly decomposes all the salts of 

 manganese, whether in the solid state or in that of solution, pro- 

 ducing peroxide. Hence it results that a strip of dry paper impreg- 

 nated with sulphate or chloride of manganese is a reagent for ozone ; 

 the paper becoming rapidly brown in an ozonized atmosphere. 

 Another and very sensible reagent, which M, Schonbein prefers, 

 is a strip of starched paper containing a very small quantity of iodide 

 of potassium. A solution of yellow ferrocyanide of potassium is 

 changed by ozone into red cyanide. A great number of metallic 

 sulphurets are rapidly converted by this substance into sulphates ; 

 such are the sulphurets of iron, lead, copper and antimony. 



According to M. Schonbein, ozone is the most powerful oxidizing 

 agent in nature. As ozone is invariably formed in the air by the 

 action of artificial electrical discharges, it should also be produced 

 throughout the atmosphere, in which natural electrical discharges 

 occur. Nothing is easier than to demonstrate the presence of ozone 

 in the atmosphere, and the variations of the quantities produced, by 

 means of the test papers described. In general the reaction is 

 greater in winter than in summer. M. Schonbein has always ob- 

 served, that during a fall of snow it is much greater than at any 

 other time. An exposure of iodized and starched paper for two 

 hours is sufficient to render it of a deep blue colour, whereas the 

 same air, enclosed in a receiver, produces no eiFect. 



It may be inquired whether the nitric acid which is formed by 

 passing electric sparks through air, as first observed by Cavendish, 

 and also that produced during storms, are due to the direct action of 

 electricity on oxygen and nitrogen, or to that of ozone on nitrogen. 



Such are the general proj)erties of a substance the composition of 

 which has hitherto escaped all methods of analysis, and which M. 

 Marignac considers as a peculiar modification of oxygen, which in- 

 creases its chemical affinities. M. Schonbein regards it as a com- 

 pound, probably containing more oxygen than oxygenated water. 

 But these are merely hypotheses which require the sanction of fresh 

 experiments. Opinions as to the nature of this substance should 

 not yet be pronounced. — Comptes Rendus, 14 Janvier, 1850. 



