The slow combustion of phosphorus and the vapour of ether produces it; and the same result takes place when oil of turpentine, in a partially filled bottle, is exposed to the direct rays of the sun. in these instances, it may be supposed that the combustible body decomposes the common oxygen, taking the antozone and liberating the ozone.

The action of sulphuric acid on peroxide of barium and permanganate of potassa also gives rise to its formation. The oxygen in peroxide of hydrogen is said to be in the state of ozone, and is the nearest approach we have to its isolation. indeed, it has been stated that the moisture condensed from ozonized air is very similar to the peroxide of hydrogen, if not identical with it. (Med. Times and Gaz., April, 1866, p. 393.)

Properties and Effects. As before stated, neither ozone nor antozone has been completely isolated; but Schonbein claims to have so far separated them from other substances as to have clearly determined their distinct existence. The most obvious property of ozone is its odour. This is peculiar, and is familiar to most persons who cultivate science as the smell developed during electrical excitation. it is thought to be considerably denser than atmospheric air, because, when a confined portion of this is ozonized by electrical flashes passed through it, a considerable diminution of bulk takes place. if a high heat is now applied, the oxygen loses the ozone, and regains its original bulk. its density is said to be one-half as great again as that of oxygen. (ibid., p. 310.) But by far the most important property of ozone, and that upon which its value both in nature and art chiefly depends, is its extraordinary power of oxidizing, in which it far exceeds all other known substances. There are, however, certain bodies, on which it has little or no power to act, possibly because their affinities are rather for antozone than ozone, or that they may be compounds in which the affinity of their bases for oxygen is already supplied with the positive variety of that element. These are called antozonides, as the alkalies and alkaline earths; while those whose affinity is for ozone are called ozonides, examples of which we have in certain metallic oxides, as those of manganese, lead, cobalt, nickel, etc. Mr. T. K. Hornidge states that, if peroxide of hydrogen, which he ranks with the antozonides, be mixed with permanganate of potassa, both are deoxidized with the escape of common oxygen; that is, the antozone of the peroxide and the ozone of the permanganate unite and neutralize each other. (ibid., April, 1861, p. 356.) Among the organic substances which ozone will not attack, unless in the presence of alkalies, are, according to M. Gorup-Besanez, mannite, glycerin, and olein, and the organic acids without nitrogen, as the acetic, butyric, palmitic, lactic, oxalic, tartaric, and citric (see Am. Journ. of Pharm., March, 1864, p. 161); and, according to Mr. Horn-idge, the pure excretory products of the body, as bile free from fat and mucus, and urea, with all the other urinary excretions, are wholly or nearly indifferent to it, while the defibrinated blood is "very greedy" of it, and fibrin is in the same category. {Med. Times and Gaz., April, 1861, p. 356.)

The oxidizing power of ozone is exemplified in the oxidizement of silver, lead, arsenic, and mercury, on the last of which it is said to act superficially; in the liberation of iodine, chlorine, and bromine from their combinations, and their own conversion into iodic, chloric, and bromic acids; in the conversion of the metallic protoxides into peroxides, and sulphurets into sulphates; and especially in the speedy and complete destruction of sulphuretted hydrogen, and all other fetid and noxious exhalations from decomposing organic substances. This it effects by oxidizing the elementary constituents of these exhalations, converting the hydrogen, carbon, nitrogen, sulphur, phosphorus, etc., which enter into the constitution of these effluvia, into water, carbonic acid, and other harmless oxides. it very speedily destroys the odour of putrefying organic substances, and renders them entirely innoxious. in the same way it purifies the atmosphere; completely destroying the exhalations of organic origin which so often disagreeably affect the air, and render it noxious to human health. it is, in fact, nature's great disinfectant, by which the putrefactive process, necessary for the conversion of dead organic matter into its original condition, is rendered harmless wherever ozone has an opportunity to act. Through the same influence it discharges organic colours.

It is not probable that ozone is in any considerable degree, at least in the dilute state in which it exists in nature, or is produced for disinfecting purposes, directly destructive or injurious to the true ferments or miasms, which are the origin of specific diseases, and which are frequently if not always lower forms of organic life. But, though it will Dot directly destroy them, it may often prove very serviceable in preventing their injurious influence over man. Thus, many of these special organized living causes of disease can live and propagate only in an impure atmosphere. it is probable that they are sustained by the organic impurities of the air, and that, if these are destroyed, they will perish for want of nutriment, and thus cease to spread. Now these impurities it is that ozone is especially calculated to destroy, and it may thus prove, as far as its influence can extend, indirectly destructive of these morbific causes, and consequently preservative to health.

Effects on the living system. The inhalation of ozone somewhat concentrated produces in man irritation or inflammation of the air-passages, attended with coryza, sore-throat, cough, etc., in other words, catarrhal symptoms more or less severe according to the intensity of the cause, and the susceptibility of the individual. in a more concentrated state, it is probably capable of producing serious inflammation of the respiratory organs; as, when tried in this way on the lower animals, it has produced such results. An impregnation of the air with ozone to the extent of 1/2000, is stated to have proved fatal to small animals. (Dr. E. S. Gail-lard, Bost. Med and Surg. Journ., Sept. 1864, p. 129.) Some observations have tended to show that epidemic influences are occasionally attended with a more than ordinarily ozonized condition of the atmosphere in the vicinity where they prevail; and some have been disposed to ascribe the peculiar influence of the north-east winds in this country, and the north-west in Europe, both coming from the Atlantic, less to the cold dampness that attends them than to an unusual degree of ozonic impregnation. But these opinions are as yet mainly speculative; not having been sufficiently supported by evidence to be admitted among established facts. it is certain that persons may live with perfect health in a highly ozonized air; but, even under such circumstances, it is possible that a sudden increase of the influence may give rise to catarrhal disease. To a deficiency of ozone in the atmosphere, the prevalence of gastro-intestinal disease, as cholera, diarrhoea, and dysentery, in certain localities has been ascribed; and such a result appears by no means improbable when it is considered that these are diseases which often originate in putrid exhalation, as from sewers, and encampments in low and wet places, which it is the peculiar function of ozone to destroy. No such operation of ozone on the system has yet been demonstrated, as could render it directly applicable to the cure of disease; and it is only as a disinfectant, in order to prevent the morbid influence of the effluvia from organic decomposition, that it is used.