WATER_ A fluid of which a cubic foot 1 weighs 1000 ounces, or 625 times more than I a cubic foot of atmospheric air, the constituents of which are one part by weight of hydrogen I and seven and a half of oxygen, and two parts 1 by bulk of hydrTen, and one of oxygen. It becomes solid at 32° of Fahrenheit, and boils, or evaporates and becomes no hotter, at though by compression it has been heated red hot. When expanded in steam, at 212° it an quires 1600 times its bulk, and presses with 1 the force of atmospheric air ; at 226° it ex pands 9000 timer., and 36,000 times at 257°. A volume of ice is made fluid by as much heat as will raise an equal volume of water 140°. Vegetables decompose it, the hydrogen forming their unctuous, resinous, and samba. roe principles, in combination with the car bon of the soil; the oxygen being evolved by the leaves, and a supply thereby kept up of what is fixed by animal respiration and corn bunion. In the ocean it is combined with one thirtieth of its weight of muriate of soda, or sea-salt ; but as the salt does not crystallize so soon as water, sea-Water remains hquid WI the thermometer is 3-5° lower than for other water. In like manner, the salt does not
evaporate at the heat which vaporises water, and therefore the two processes of crystallizing and evaporating separate the water from the en salt. hence the clouds which rise from the sea rain fresh water, and water evaporated by art yields salt in the proportion of one ton from tty-five of- water. In crystallizing, vacuities arise, which enlarge the bulk; hence frozen water splits rocks and trees, and ice floats upon water. Water combines with iron, sulphur, lime, and various subAanon, under a great variety of names; hard water arises from carbonic acid in water, which then combines with lime. Waters are called hard when they contain a salt which decomposes the soap, instead of dissolving it. The deduc tions drawn in regard to the decomposition of water from the experiment of discharging a galvanic battery through water, are by some considered erroneous.