ARC 
of Zante, 64 miles fouth-wett of Corinth, and 12 north of 
Navarin. Lat. 37.24. N. Ion. 21.42. E. 
ARC AN'GlS,y. in the Turkifh armies an inferior kind 
of infantry, which ferve as cnfans perdus , and to lrarafs and 
pillage the enemy’s frontiers. The Arcangis are an order 
inferior to the Janifaries ; and, when any of them diffin- 
guifli themfelves, they are ufually preferred into the Jani- 
laries order. They have no pay, but fubfift on their plunder. 
ARCA'NUM, _/". A Latin word, lignifying a fecret. 
Its plural is arcana. 
Arca'num, anciently a villa of QT-icero,Tully’s bro¬ 
ther, in Latium ; now Arce, in the Te-rra di Lavoro, in the 
kingdom of Naples, on the borders of the Campagnia di Ro¬ 
ma, on the river Melpis, between Arpinum and Aquinum. 
Arca'num Coralli'num, /. This name has been 
given to red precipitate, on which fpirit of wine has been 
two or three times burnt, with an intention of rendering 
it milder. 
Arca'num Duplica'tum,^ A name formerly given 
to the combination of vegetable alkali and vitriolic acid, 
and molt commonly called, vitriolated tartar. 
AR'CAS, in fabulous hi dory, the fon of Jupiter and 
the nymph Califto. He reigned in Pelafgia, which from 
him was called Arcadia; and, after his death, Jupiter 
made him a conftellation, called the Little Bear, placed in 
heaven near his mother. See Arcturus. 
ARC-BOUTANT, f. is a kind of arched buttrefs, 
formed of a flat arch, or part of an arch, abutting againft 
the feet or fides of another arch or vault, to fupport them, 
and prevent them from burfting or giving way. 
ARCE'SILAUS, a celebrated Greek philofopher, a- 
bout 300 years before the Chriflian era, was born at Pitane, 
in Eolis. He founded the fecond academy, which is called 
the Jecond fchool. He was a man of great erudition, and 
well verfed in the writings of the ancients. He was re¬ 
markable for the feverity of his criticifms; but neverthe- 
lefs he knew how to accommodate himfelf to the age, and 
purfue all the allurements of pleafure; He had a great 
number of difciples. His doftrines were different in feveral 
refpeifts from thofe of the ancient fchool; and, perhaps, 
he was led into this diverffty of opinions by many capital 
errors in the ancient fchool, fuch as the incredible arro¬ 
gance of the dogmatifts, who pretended to allign caufes 
for all things ; the myfterious air they had thrown upon 
the doctrine of ideas; the entirely difearding the teftimony 
of the lenfes ; the objections of the Pyrrhonefts, who now 
began to broach their opinions ; the powerful oppofition 
of the Stoics and Peripatetics, who difeovered the feeble 
parts of the academic philofophy. Thefe might have gi¬ 
ven caufe to reform the ancient fchool, and to found a new- 
one. Arceiilaus was fucceeded by his difciple Lacydes. 
ARCE 1 UL', a village three miles fouth of Paris, re¬ 
markable for an aqueduCt, which is thought to equal the 
works of the ancient Romans. It was built in 1624, by 
Mary de Medicis, and fupplies different parts of Paris 
with water. 
ARCH, f. [arcus, Lat. ] Part of a circle, not more than 
the half.—The mind perceives, that an arch of a circle is 
lefs than the whole circle, as clearly as it does the idea of 
a circle. A building open below and clofed above, {land¬ 
ing by the form of its own curve, ufed for bridges and 
other works: 
Let Rome in Tiber melt, and the wide arch 
Of the rais’d empire fall! here is my fpace. Shakefpeare. 
The {ky, or vault of heaven: 
Hath nature given them eyes 
To fee this vaulted arch , and the rich cope 
Of fea and land ? Shakefpeare. 
Arch, [from Gr.] A chief: obfolcte. 
The noble duke, my matter. 
My worthy arch and patron comes to-night. Shakefpeare. 
To Arch, v.a. [arcuo, Lat.J To build arches. See 
Architecture. To cover with arches,—The proud 
Vol. II. No. .56. 
river which makes her bed at her feet, is arched over with 
fuch a curious pile of ftones, that conlidering the rapid 
courfe of the deep ftream that roars under it, it may well 
take place among the wonders of the world. Howell. To 
form into arches.—Fine devices of arching water without 
{pilling, and making it rife in feveral forms of feathers 
and drinking-glaffes, be pretty things to look on, but no¬ 
thing to health and fweetnefs. Bacon. 
Arch, adj. [from chief.] Chief; of the fiift 
clafs : 
The tyrannous and bloody ail is done; 
The molt arch deed of piteous maffacre, 
That ever yet this land was guilty of. Shakefpeare. 
Waggiffi; mirthful; triflingly mifehievous. This figni- 
fication it feems to have gained, by being frequently ap¬ 
plied to the boy moll remarkable for his pranks; as, The 
arch rogue; unlefs it be derived from Archy, the name of 
the jefter to Charles I.—Eugenio fet out from the univer- 
flty; he had the reputation of an arch lad at fchool. Szoi/t. 
Arch, f. [from or Gr.] In compolition, 
fignifies chief, or of the firft clafs ; as, archangel, arch- 
bijhop. It is pronounced varioutty with regard to the ck, 
which before a confonant found as in cheefe, as archdeacon ; 
before a vowel like k , as archangel. 
Arch, or Arc, in geometry, a part of any curve line; 
as, of a circle, or elliplis, or the like. It is by means of 
circular arcs, or arches, that all angles are meafured ; the 
arc being deferibed from the angular point as a centre. 
For this purpofe, every circle is fuppofed to be divided 
into 360 degrees, or equal parts ; and an arch, or the angle 
it fubtends and meafures, is eftimated according to the 
number of degrees it contains : thus, an arc, or angle, is 
faid to be of 30, or 80, or 100, degrees. Circular arCs are 
alfo of great ufe in finding of fluents. 
Arch, in architecture, a concave ftru6tiu:e, raifed or 
turned upon a mould, called the centering, in form of the 
arch of a curve, and ferving as the inward fupport of 
fome fuperffruiSture. Sir Henry Wotton fays, An arch is 
nothing but a narrow or contracted vault; and a vault is 
a dilated arch. See Architecture. 
Arch of Direction, in aftrology, is a portion of the 
equator lying between two points in the heavens, one of 
which is the place of the fignificator, and the other of the 
promiffor. 
ARCHAN'GEL, f. [archange, Fr. archangelus, Lat. 
of uqxjuv, chief, and apye\<&, angel, Gr.] An 
angel occupying the eighth rank in the celeftial hierarchy. 
See Angel and Hierarchy. 
Archangel, a city ofRuflia,in the province of Dwina, 
fituated on the eaft fide of the river Dwina, ab<»ut fix miles 
from the White Sea, and 400 north-eaft of Peterfburg, in 
lat. 64. 34. N. Ion. 39. o. E. The city extends about three 
miles in length and one in breadth. It is rich and popu¬ 
lous, and is a metropolitan fee. It rofe from a caftle built 
on the fpot by Balilowitz II. to proteitt the increafing trade 
brought there by the difeovery of the White Sea by the 
Englifh, and took its name from a monaftery built in ho¬ 
nour of Michael the archangel. Before this period, the 
commercial intercourfe between Ruflia and the northern 
parts of Europe had been long carried on by the Hanfeatic 
towns, which ufually failed to Revel or Narva, and from 
thence paffed through Dorpt to Plefcof and Novogorod, 
where their fadtories were effablifhed. The accidental 
difeovery of Archangel, in 1553, deprived the Hanfeatic 
towns of a great part of this lucrative commerce, and 
transferred it to the Englifh. On the nth of May, in the 
above-mentioned year, three fhips failed from Deptford, 
to explore the northern feas, under the command of Sir 
Hugh Willoughby. Two of thefe veffels penetrated as 
high as the 7 2d degree of latitude, to the coaft of Spitz - 
bergen ; and, being afterwards forced by ffrefs of weather 
into the bay of the river Arzina in Ruffian Lapland, both 
their crews were frozen to death. Richard Chancellor, 
who commanded the other fhip, called the Bonaventure, 
N difeovering 
