precede cause, cause must precede effect, and there must
be an instant when cause is not effective, that is, is not
itself. By these and similar arguments he arrives at
the fundamental principle of Scepticism, the radical and
universal opposition tion of causes; panti logo logos
antikeitai. Having reached this conclusion, he was able to
assimilate the physical theory of Heraclitus, as is explained
in the Hypotyposes of Sextus Empiricus. For admitting that
contraries co-exist for the perceiving subject, he was able
to assert the co-existence of contrary qualities in the same
object. Having thus disposed of the ideas of truth and
causality, he proceeds to undermine the ethical criterion,
and denies that any man can aim at Good, Pleasure or Happiness
as an absolute, concrete ideal. All actions are product
of pleasure and pain, good and evil. The end of ethical
endeavour is the conclusion that all endeavour is vain and
illogical. The main tendency of this destructive scepticism
is essentially the same from its first crystallization by
Aenesidemus down to the most advanced sceptics of to-day (ree
SCEPTICISM). For the immediate successors of Aenesidemus
see AGRIPPA, SEXTUS EMPIRICUS. See also CARNEADES and
ARCESILAUS. Of the Porroneioi logoi nothing remains; we
have, however, an analysis in the Myriobiblion of Photius.
See Zeller's History of Greek Philosophy; F. Saisset,
AEnesideme, Pascal, Kant; Ritter and Preller, sec. sec. 364-87O.
AEOLIAN HARP (Fr. harpe eolienne; Ger. Aolsharfe, Windharfe;
Ital. arpa d'Eolo), a stringed musical instrument, whose
name is derived from Aeolus, god of the wind. The aeolian
harp consists of a sound-box about 3 ft long, 5 in. wide,
and 3 in. deep, made of thin deal, or preferably of pine, and
having beech ends to hold the tuning-pins and hitch-pins.
A dozen or less catgut strings of different thickness, but
tuned in exact unison, and left rather slack, are attached
to the pins, and stretched over two narrow bridges of hard
wood, one at each end of the sound-board, which is generally
provided with two rose sound-holes. To ensure a proper
passage for the wind, another pine board is placed over the
strings, resting on pegs at the ends of the sound-board, or
on a continuation of the ends raised from 1 to 3 in. above the
strings. Kaufmann of Dresden and Heinrich Christoph Koch,
who improved the aeolian harp, introduced this contrivance,
which was called by them Windfang and Windflugel; the
upper board was prolonged beyond the sound-box in the shape
of a funnel, in order to direct the current of air on to the
strings. The aeolian harp is placed across a window so that
the wind blows obliquely across the strings, causing them to
vibrate in aliquot parts, i.e. (the fundamental note not
being heard) the half or octave, the third or interval of the
twelfth, the second Octave, and the third above it, in fact
the upper partials of the strings in regular succession. With
the increased pressure of the wind, the dissonances of the
11th and 13th overtones are heard in shrill discords, only
to give place to beautiful harmonies as the force of the wind
abates. The principle of the natural vibration of strings
by the pressure of the wind was recognized in ancient times;
King David, we hear from the Rabbinic records, used to
hang his kinnor (kithara) over his bed at night, when it
sounded in the midnight breeze. The same is related of St
Dunstan of Canterbury, who was in consequence charged with
sorcery. The Chinese at the present day fly kites of various
sizes, having strings stretched across apertures in the
paper, which produces the effect of an aerial chorus.
See Athanasius Kircher, Musurgia Universalis, where the aeolian
harp is first described (1602-1608), p. 148; Mathew Young, Bishop
of Clonfert, Enquiry into the Principal Phenomena of Sounds and
Musical Strings pp. 170-182 (London, 1784); Gottingen Pocket
Calendar (1792); Mendel's Musikalisches Conversations-Lexikon,
article ``Aeolsharfe.', An illustration is given in Rees'
Encyclopedia, plates, vol. ii. Misc. pl. xxv (K. S.)
AEOLIS (AEOLIA), an ancient district of Asia Minor,
colonized at a very early date by Aeolian Greeks. The name was
applied to the coast from the river Hermus to the promontory
of Lecture, i.o. between Ionia to S. and Troas to N. The
Aeolians founded twelve cities on the mainland, including
Cyme, and numerous towns in Mytilene: they were said also
to have settled in the Troad and even within the Hellespont.
AEOLUS, in Greek mythology, according to Homer the son of
Hippotes, god and father of the winds, and ruler of the island of
Aeolia. In the Odyssey (x. I) he entertains Odysseus,
gives him a favourable wind to help him on his journey, and
a bag in which the unfavourable winds have been confined.
Out of curiosity. or with the idea that it contains valuable
treasures, Odysseus' companions open the bag; the winds escape
and drive them back to the island, whence Aeolus dismisses them
with bitter reproaches. According to Virgil, Aeolus dwells on
one of the Aeolian islands to the north of Sicily, Lipara or
Strongyle (Stromboll), where he keeps the winds imprisoned in
a vast cavern (Virgil, Aen. i. 52). Another genealogy makes
him the son of Poseidon and Arne, granddaughter of Hippotes,
and a descendant of Aeolus, king of Magnesia in Thessaly, the
mythical ancestor of the tribe of the Aeolians (Diodorus iv. 67).
AEON, a term often used in Greek (aion) to denote
an indefinite or infinite duration of time; and hence, by
metonymy, a being that exists for ever. In the latter sense
it was chiefly used by the Gnostic sects to denote those
eternal beings or manifestations which emanated from the
one incomprehensible and ineffable God. (See GNOSTICISM.)
AEPINUS, FRANZ ULRICH THEODOR (1724-1802), German natural
philosopher, was born at Rostock in Saxony on the 13th of December
1724. He was descended from John Aepinus (1499-1553), the
first to adopt the Greek form (aipernos) of the family name
Hugk or Huck, and a leading theologian and controversialist
at the time of the Reformation. After studying medicine for
a time, Franz Aepinus devoted himself to the physical and
mathematical sciences, in which he soon gained such distinction
that he was admitted a member of the Berlin academy of
sciences. In 1757 he settled in St Petersburg as member of
the imperial academy of sciences and professor of physics, and
remained there till his retirement in 1798. The rest of his
life was spent at Dorpat, where he died on the 10th of August
1802. He enjoyed the special favour of the empress Catherine
II., who appointed him tutor to her son Paul, and endeavoured,
without success, to establish normal schools throughout the
empire under his direction. Aepinus is best known by his
researches, theoretical and experimental, in electricity
and magnetism, and his principal work, Tentamen Theoriae
Electricitatis et Magnetismi, published at St Petersburg in
1759, was the first systematic and successful attempt to apply
mathematical reasoning to these subjects. He also published a
treatise, in 176I, De distributione caloris per tellurem,
and he was the author of memoirs on different subjects in
astronomy, mechanics, optics and pure mathematics, contained
in the journals of the learned societies of St Petersburg and
Berlin. His discussion of the effects of parallax in
the transit of a planet over the sun's disc excited great
interest, having appeared (in 1764) between the dates of the
two transits of Venus that took place in the 18th century.
AEQUI, an ancient people of Italy, whose name occurs
constantly in Livy,s first decade as hostile to Rome in the
first three Centuries of the city's existence. They occupied
the upper reaches of the valleys of the Anio, Tolenus and
Himella; the last two being mountain streams runing northward
to join the Nar. Their chief centre is said to have been
taken by the Romans about 484 B.C. (Diodorus xi. 40) and
again about ninety years later (id. xiv. 106), but they
were not finally subdued Until the end of the second Samnite
war (Livy ix. 45,; x. 1; Diod. xx. 101), when they seem to
have received a limited form of franchise (Cic. Off. i.
II, 35). All we know of their subsequent political condition
is that after the Social war the folk of Cliternia and Nersae
appear united in a res Publica Aequiculorum, which was a
municipium of the ordinary type (C.I.L. ix. p. 388). The
Latin colonies of Alba Fucens (304 B.C.) and Carsioll (298
B.C.) must have spread the use of Latin (or what passed as
such) all over the district; through it by the chief (and for
some time the only) route (Pia Valeria) to Luceria and the
south. Of the language spoken by the Aequi before the Roman
conquest we have no record; but since the Marsi (q.v.), who
lived farther east, spoke in the 3rd century B.C. a dialect
closely akin to Latin, and since the Hernici (q.v.), their
neighbours to the south-west, did the same, we have no ground
for separating any of these tribes from the Latian group
(see LATINI). If we could be certain of the origin of the
a in their name and of the relation between its shorter
and its longer form (note that the i in Aequicidus is
long--Virgil, Aen. vii. 74----which seems to connect it
with the locative of aequum ``a plain,'' so that it would
mean ``dwellers in the plain''; but in the historical period
they certainly lived mainly in the hills), we should know
whether they were to be grouped with the q or the p
dialects, that is to say, with Latin on the one hand, which
preserved an original q, or with the dialect of Velitrae,
commonly called Volscian (and the Volsci were the constant
allies of the Aequi), on the other hand, in which, as in the
Iguvine and Samnite dialects, an original q is changed into
p. There is no decisive evidence to show whether the q
in Latin aequus represents an Indo-European q as in Latin
quis, Umbro-Volsc. pis, or an Indo-European k+u as in
equus, Umb. ekvo-. The derivative adjective Aequicus
might be taken to range them with the Volsci rather than the
Sabini, but it is not clear that this adjective was ever used
as a real ethnicon; the name of the tribe is always Aeqai,
or Aequicoli. At the end of the Republican period the Aequi
appear, under the name Aequiculi or Aequicoh, organized as a
municipium, the territory of which seems to have comprised
the upper part of the valley of the Salto, still known as
Cicolano. It is probable, however, that they continued to
live in their villages as before. Of these Nersae (mod.
Nesce) was the most considerable. The polygonal terrace
walls, which exist in considerable numbers in the district,
are shortly described in Romische Mitteilungen (1903), 147
seq., but require further study. See further the articles
MARSI, VOLSCI, LATINI, and the references there given; the
place-names and other scanty records of the dialect are collected
by R. S. Conway. The Italic Dialects, pp. 300 ff. (R. S. C.)
AERARII (from Lat. aes, in its subsidiary sense of
``polltax''), originally a class of Roman citizens not included
in the thirty tribes of Servius Tullius, and subject to a
poll-tax arbitrarily fixed by the censor. They were (1)
the inhabitants of conquered towns which had been deprived
of local self-government, who possessed the jus eonubii
and ius commercii, but no political rights; Caere is said
to have been the first example of this (353 B.C.); hence
the expression ``in tabulas Caeritum referre'' came to mean
``to degrade to the status of an aerarius'': (2) full
