C (from Gr. [Greek: authentes], one who does a thing himself),
genuine, as opposed to counterfeit, true or original. In music it is one of
the terms used for the ecclesiastical modes. The title of _Authentics_ was
also used for Justinian's _Novells_.

AUTOCEPHALOUS (from Gr. [Greek: autos], self, and [Greek: kephale] head),
of independent headship, a term used of certain ecclesiastical
functionaries and organizations.

AUTOCHTHONES (Gr. [Greek: autos], and [Greek: chthon], earth, _i.e._ people
sprung from earth itself; Lat. _terrigenae_; see also under ABORIGINES),
the original inhabitants of a country as opposed to settlers, and those of
their descendants who kept themselves free from an admixture of foreign
peoples. The practice in ancient Greece of describing legendary heroes and
men of ancient lineage as "earthborn" greatly strengthened the doctrine of
autochthony; for instance, the Athenians wore golden grasshoppers in their
hair in token that they were born from the soil and had always lived in
Attica (Thucydides i. 6; Plato, _Menexenus_, 245). In Thebes, the race of
Sparti were believed to have sprung from a field sown with dragons' teeth.
The Phrygian Corybantes had been forced out of the hill-side like trees by
Rhea, the great mother, and hence were called [Greek: dendrophueis]. It is
clear from Aeschylus (_Prometheus_, 447) that primitive men were supposed
to have at first lived like animals in caves and woods, till by the help of
the gods and heroes they were raised to a stage of civilization.

AUTOCLAVE, a strong closed vessel of metal in which liquids can be heated
above their boiling points under pressure. Etymologically the word
indicates a self-closing vessel ([Greek: autos], self, and _clavis_, key,
or _clavus_, nail), in which the tightness of the joints is maintained by
the internal pressure, but this characteristic is frequently wanting in the
actual apparatus to which the name is applied. The prototype of the
autoclave was the digester of Denis Papin, invented in 1681, which is still
used in cooking, but the appliance finds a much wider range of employment
in chemical industry, where it is utilized in various forms in the
manufacture of candles, coal-tar colours, &c. Frequently an agitator,
passing through a stuffing-box, is fitted so that the contents may be
stirred, and renewable linings are provided in cases where the substances
under treatment exert a corrosive action on metal.

AUTOCRACY (Gr.