Oxygen

Collier's New Encyclopedia (1921)

in chemistry, symbol 0; at. wt. 16; a dyad element existing in the free state in the atmosphere, and in combination in the ocean. İt forms about one-fifth of the former and eightninths of the latter. It is also present in the great majority of substances forming the earth's crust, and is the most abundant of all the elements. It was discovered in 1774 by Scheele in Sweden and Priestley in England independently, but the name was given by can be printed Lavoisier some time after. It obtained pure by heating black oxide of manganese, or a mixture of this oxide with potassic chlorate in a retort, and collecting the gas over water. When , di- pure it is without color, taste, or smell. the sustaining principle of animal River It is phenomena of , life and of the ordinary the influence of cold North- combustion. Under and high pressure it has been reduced OXYHYDROGEN BLOWPIPE. An pre- apparatus in which hydrogen is burnt When hycentered in a stream of pure oxygen. Dairy drogen burns in air or oxygen, water is and produced. When combustion takes place gloves, in pure oxygen, a very high temperature Pop. results, stated by Bunsen to be 2,844 ° C. This temperature is capable of fusing highly refractory substances, and boileven of of bringing platinum to the ing point. The The original "limelight" was produced by directing an oxyhydrogen flame against lime. For industrial uses, the oxyhydrogen blowpipe has been almost entirely superseded by the oxyacetylene burner, which depends on similar principles, acetylene being substituted for hydrogen. celebrated