5, 6, 10, and _Sulla_, 28; Cicero, _ad Fam._ ix.
21; Eutropius, v. 8, 9; Orosius, v. 20; Valerius Maximus, v. 3. 5, ix.
13. 2; art. SULLA, L. CORNELIUS.

CARBOHYDRATE, in chemistry, the generic name for compounds empirically
represented by the formula C_{x}(H2O)_{y}. They are essentially
vegetable products, and include the sugars, starches, gums and
celluloses (q.v.).

CARBOLIC ACID or PHENOL (hydroxy-benzene), C6H5OH, an acid found in the
urine of the herbivorae, and in small quantity in _castoreum_ (F.
Wohler, _Ann._, 1848, 67, p. 360). Its principal commercial source is
the fraction of coal-tar which distils between 150 and 200 deg. C., in
which it was discovered in 1834 by F. Runge. In order to obtain the
phenol from this distillate, it is treated with caustic soda, which
dissolves the phenol and its homologues together with a certain quantity
of naphthalene and other hydrocarbons. The solution is diluted with
water, and the hydrocarbons are thereby precipitated and separated. The
solution is then acidified, and the phenols are liberated and form an
oily layer on the surface of the acid. This layer is separated, and the
phenol recovered by a process of fractional distillation. It may be
synthetically prepared by fusing potassium benzene sulphonate with
caustic alkalis (A. Kekule, A. Wurtz); by the action of nitrous acid on
aniline; by passing oxygen into boiling benzene containing aluminium
chloride (C. Friedel and J.M. Crafts, _Ann. Chim. Phys._, 1888 (6) 14,
p. 435); by heating phenol carboxylic acids with baryta; and, in small
quantities by the oxidation of benzene with hydrogen peroxide or nascent
ozone (A.R. Leeds, _Ber._, 1881, 14, p. 976).

It crystallizes in rhombic needles, which melt at 42.5-43 deg. C., and
boil at 182-183 deg. C.; its specific gravity is 1.0906 (0 deg. C.). It
has a characteristic smell, and a biting taste; it is poisonous, and
acts as a powerful antiseptic. It dissolves in water, 15 parts of water
dissolving about one part of phenol at 16-17 deg. C., but it is miscible
in all proportions at about 70 deg. C.; it is volatile in steam, and is
readily soluble in alcohol, ether, benzene, carbon bisulphide,
chloroform and glacial acetic acid. It is also readily soluble in
solutions of the caustic alkalis, slightly soluble in aqueous ammonia
solution, and almost insoluble in sodium carbonate solution. When
exposed in the moist condition to the air it gradually acquires a red