-93); Wiedemann, Ueber die 7aturwissenschaften bei den Arabern (Hamburg. 1890); Suter. Die Mathemaiiker und Astrotwincn der Araber (Leipzig. 1900).
ARABIC NU'MERALS. See Numerals; and Algorism.
ARABIC VER'SIONS. See Bible.
AR'ABIN. The chief constituent of giim-arabic, obtained by precipitating an acidulated aqueous solution "of gum-arabic with ordinary alcohol.
ARABI PASHA. a-ra'be pa-shii', properly
Ahmed Arabi (c. 1837—). Leader of the na-
tional party in Egypt in 1882. He was born of
fellah parents in Lower Egj'pt, and his early
youth was spent as a laborer. He sen'ed for twelve
years as a private soldier in the Egyptian army,
and gradually rose to the rank of colonel. He took
advantage of the discontent which prevailed in
Egypt on account of the foreign influence to
organize a rebellion on the issue of "Egypt for
the Egyptians." The lack of energy shown by
the Khedive Tewfik permitted Arabi to acquire
great influence. He participated in the revolt
against Xubar Pasha, obtained the removal of
the ministry, and entered the new cabinet as
minister of war (1882). In this position he be-
came a virtual autocrat, setting aside the Anglo-
French financial control. Enghind now inter-
vened and a war ensued. On July 11-12, 1882,
an English fleet bombarded Alexandria. Arabi
withdrew, and the British undertook a vigorous
campaign against him, completely defeating him
September 13. 1S82, at Tel-el-Kebir. He surren-
dered the following day, and a sentence of death
was passed upon him, but it was commuted to
life exile in Ceylon. The movement he had
headed collapsed! and its only result was the
permanent estalilishment of British control in
Ewypt. He was pardoned by the British Govern-
ment in December, 1900, and permitted to re-
turn to Egypt.
Consult: Long, The Three Prophets — Chinese GordoH, Mohammed Ahmed {el Mahdi). AraU Pusha (ew York, 1884): Broadley, How ^Ye Defeated Arabi und His Friends (London, 1884). See Egypt.
ARABKIR, ii'rab-ker'. A town of Asiatic
Turkev, about one lunulred and seventy miles
northwest of Diarbekr (Map: Turkey in Asia,
H 3 ) . It lies on the route from Aleppo to Trebi-
zond and is of considerable commercial impor-
tance. Population estimated at from 23,000 to
30,000, including a considerable number of
Armenians.
AR'ABY. A poetical form, especially cur-
rent in the Renaissance, for Arabia.
ARACAJTJ, ii'ra-ka-zhoo'. The capital and
cliief port of the Brazilian State of Sergipe, situ-
ated aliout seven miles from the coast on the
river Cotindiba (Map: Brazil, K 0). The city is
regularly built and ccmtains an agricultural
school. It is connected by rail with Capella and
Signao Diaz in the interior, and has an estimated
population of (iOOO, including a number of In-
dians.
AR'ACAN’. See Abakan.
ARACARI, a'ra-kii're (Port.). A toucan of
the genus Pteroglossus. See Toucan.
ARACATf, a'r:i-ca-te'. A port in the State
of Ceara, Brazil, on the river .Jaguaribe. ten miles
from its mouth, and seventy-five miles southeast
of Ceara (Map: Brazil, K 4). Its harbor is shal-
low, with a shifting bar at the entrance, but can
be entered at high tide. Its exports are hides,
cotton, and sugar. It maintains regular steam-
ship communication with Pernambuco. and has a
population of about (>000. It was foimded in
1723.
ARA'CE.Æ. See Abum.
ARACHIS, ar'a-kis. See Peanut.
ARACHNE, a-rak'ne (Gk. Apaxurj. arachne,
lit. spider). The mythical Lydian girl who. hav-
ing excited Athene's anger by challenging her to
a contest in weaving, was changed by the irate
goddess to a spider. Her fate, and especially her
skill with the shuttle and the loom, have been a
favorite tlienie among the poets.
ARACH'NIDA (Gk. dpax^v, arachiic, a
spider). A class of air-breathing arthropods
including the mites, scorpions, spiders, and a few
other less well-known groups. The typical
Arachnida have the head and the thorax more
or less fused into a "cephalothorax," four pairs
of legs, and no aiitenn;^, the maxillary palp.,
functioning as antenn:!'. The eyes are all simple,
and vary in number from two to twelve. By the
number and arrangement of these eyes the
species of spiders are determined. The abdomen
possesses no true legs, but the three aljdomiiial
spinnerets of s]>iders are homologous with legs.
Besides the spinneret-glands in the abdominal
region of spiders there are poison-glands in the
last abdominal scgiiieut of scorpions, located at
the base of the sting. In other forms the poison
is emitted tlirough the hollow Jaws. The
Arachnida breathe by means of trachea?, like
other insects, or by means of sacklike bodies
called "lungs" that open on the under side of the
abdomen; but some forms breathe by both
tracheie and lungs. All the Arachnida are carniv-
orous save some of the mites, which live on plant-
sap. Most of the animal-feeders jirey upon
other insects, and hence are the friends of agri-
culture. A few forms are parasitic on warm-
blooded vertebrates and fish, and eau.se or accom-
pany such diseases as itch and mange. The his-
tory of this class goes back to Palteozoic times.
Classifieation. — The Arachnida are divided into
seven orders: (1) Solpugida, or wind scor-
pions; (2) Scorpionida, or scorpions; (3) Pseu-
doseorpionida. book-scorpions; (4) Pcdipalpida,
or whip-scorpions; (.3) Phalangida, or harvest-
men; (6) Araneida. or spiders; and (7) Acarida,
or mites. The following groups are believed by
many to fall into the class Arachnida. but their
relationships are doubtful: Linguatulida, or
tongue-parasites of the dog; Tardigrada, or
w ater-bears; Pycnogonida, or sea-spiders;
Xiphosura. or king-crabs. See MiTEs; Scor-
pions: Spiders: Harvest-Man.
ARACH'NOID MEM'BRANE. One of the three coverings of tlio Itrain and spinal cord. It is a thin, glistening membrane, which, by its parietal layer, adheres inseparably to the duramater on its outer side, and more loosely to the pia-mater, which is between it and the brain substance. Between the pia-mater and the araelinoid membrane in some situations there are considerable intervals (sub-arachnoid spaces). See C'erebro-Spixal Fluid; Nervous System.
