correspond more nearly to 10KClO3
= 6KClO4 + 4KCl + 3O2. The decomposition is rendered more easy and
regular by mixing the salt with powdered manganese dioxide. The salt
finds application in the preparation of oxygen, in the manufacture of
matches, for pyrotechnic purposes, and in medicine. Sodium chlorate,
NaClO3, is prepared by the electrolytic process; by passing chlorine
into milk of lime and decomposing the calcium chlorate formed by sodium
sulphate; or by the action of chlorine on sodium carbonate at low
temperature (not above 35 deg. C). It is much more soluble in water than
the potassium salt.

Potassium chlorate is very valuable in medicine. Given in large doses it
causes rapid and characteristic poisoning, with alterations in the blood
and rapid degeneration of nearly all the internal organs; but in small
doses--5 to 15 grains--it partly undergoes reduction in the blood and
tissues, the chloride being formed and oxygen being supplied to the
body-cells in nascent form. Its special uses are in ulceration of the
mouth or tongue (_ulcerative stomatitis_), tonsillitis and pharyngitis.
For these conditions it is administered in the form of a lozenge, but
may also be swallowed in solution, as it is excreted by the saliva and
so reaches the diseased surface. Its remarkable efficacy in healing
ulcers of the mouth--for which it is the specific--has been ascribed to
a decomposition effected by the carbonic acid which is given off from
these ulcers. This releases chloric acid, which, being an extremely
powerful antiseptic, kills the bacteria to which the ulcers are due.

CHLORINE (symbol Cl), atomic weight 35.46 (O = 16), a gaseous chemical
element of the halogen group, taking its name from the colour,
greenish-yellow (Gr. [Greek: chloros]). It was discovered in 1774 by
Scheele, who called it _dephlogisticated muriatic acid_; about 1785,
C.L. Berthollet, regarding it as being a compound of hydrochloric acid
and oxygen, termed it _oxygenized muriatic acid_. This view was
generally held until about 1810-1811, when Sir H. Davy showed definitely
that it was an element, and gave it the name which it now bears.

Chlorine is never found in nature in the uncombined condition, but in
combination with the alkali metals it occurs widely distributed in the
form of rock-salt (sodium chloride); as sylvine and carnallite, at
Stassfuert; and to a smaller extent in various other minerals such as
matlockite and horn-mercury. In th