296 COMPOSITION OF WATER. 



in water are dependent upon its solvent powers. The 

 waters of the ocean are saline from holding dissolved 

 various saline compounds, which are received in part 

 from, and imparted also to, the marine plants. Perfectly 

 pure water is without taste : even the pleasant character 

 of freshly-drawn spring- water is due to the admixture 

 of atmospheric air and carbonic acid. The manner in 

 which water absorbs air is evidently due to a peculiar 

 physical attractive force, the value of which we do not 

 at present clearly perceive or correctly estimate. It is 

 chemically composed of two volumes of hydrogen gas 

 the lightest body known, and at the same time a highly 

 inflammable one united with one volume of oxygen, 

 which excites combustion, and continues that action, 

 producing heat andlight, with great energy. By weight, 

 one part of hydrogen is united with eight of oxygen, or 

 in 100 parts of water we find 88*9 oxygen, and IT1 of 

 hydrogen gas. That two such bodies should unite to 

 furnish the most refreshing beverage, and indeed -the 

 only natural drink for man and animals, is one of <the 

 extraordinary facts of science. Hydrogen will not sup- 

 port life we cannot breathe it and live ; and oxygen 

 would over-stimulate the organic system, and, producing 

 a kind of combustion, give rise to fever in the animal 

 frame ; but, united, they form that drink, for a drop of 

 which the fevered monarch would yield his diadem, and 

 the deprivation of which is one of the most horrid cala- 

 mities that can be inflicted upon any living thing. Water 

 appears as the antagonist principle to fire, and the 

 ravages of the latter are quenched by the assuaging 

 powers of the former; yet a mixture of oxygen and 

 hydrogen gases, in the exact proportion in which they 

 form water, explodes with the utmost violence on the 

 contact of flame, and, when judiciously arranged, produces 

 the most intense degree of heat known ; such is the 

 remarkable difference between a merely mechanical 

 mixture and a chemical combination. Beyond this, we 





