ORB 
Brest that of Mercury 7 degrees ; that of the Moon 12 
degrees 30 minutes. 
rs, in Pointed Archite@ure, the fame as knot or bofs. 
See Kno 
Ors, in a Tadiice. See Round BATTALION. ‘ 
Ors, in Geography, a river of France, which rifes in the 
N. part of the department of the Allier; 8 miles N.W. 
of Lodeve, and runs into the Mediterranean, 8 miles below - 
h 
Beziers. 
ORBE, a river of Switzerland, which rifes in mount 
Jura, paffes the lake el Neufchatel and Bien nne, and runs 
into the Aar; 3 m 
Berne. —Alfo, a ai "of Switzerland, in the canton of 
Berne, fituated on the above river. According to anti- 
quaries, this was the moft ancient town, and once the moft 
aries 
powerful of all Helvetia: it was called “ Urba,” and was 
the capital of the « Pagus Urbigenus ;”” but it has no re- 
mains of its ancient {plendour. Some antique fortifications, 
an old caftle, and a round tower, are probably works of 
later times, when this country was divided into a number of 
feudal fovereignties. ‘The fituation of the town is romantic ; 
its fingle- ates bridge projeGting over the Orbe, the wild 
fcenery on the banks of this river, the frequent cataracts, 
and oa piétu urefque view in the environs, are all interefting 
° Orbe, which is governed by its own magiftrates, 
is Se rifed within the bailliage of Echalons, belonging to 
Berne and Friburgh. In this town is an infirmary, formed 
by M. Venel, an eminent furgeon, for the reception of per- 
fons with diltorted limbs. Veuel has contrived a machine 
to embrace the patient’s limbs when in bed, and which is 
conlkriGed fo as to a without difturbing their reft. This 
contrivance, it is faid, has performed many cures; 5 miles 
-W. of Yverdun. —Alfo, a town of Germany, celebrated 
for its falt. works; 26 miles E. of Frankfort on the Maine. 
n the oo of the 
rit of 
lace me 
3600, and the canton 1 53047 inhabitants, on a territory of 
180 kiliometres, in 27 communes. 
RBICULAR Lear, in Bota See LEA 
ne ARIS, in Anaiony, a 1 epithet applied to the 
muf{cles which furround the openings of fome organs ; as 
the a oris or ag ee ea at the mouth. See Drciv- 
TITIO dE 
Onc LARIS, i in Botany, a name given by fome authors 
to the edited or cyclamen, called in Englifh fow-bread. 
See Cycia 
ORBI ULUS CrLraRIs, in Anatomy, a circular adhefion 
between the choroid coat and fclerotica of the eye. See 
ORBIEU, i in Geography, a river of France, which rifes 
in the israel of the Eaftern ee and runs into the 
wer of Narbon 
BIGA, a river of Spain, wel runs into the Duero, 
near ean anciently called ‘¢ Urbicus.”’ 
» a lake of the ifland of Corfica, near the fea, 
on the E. coaft; 27 milesS.E, of Corte. 
ORBIS, in Ichthyology, a {pecies of Chatodon ; which 
fee—Alfo, a name given to feveral {pecies of Diodon ; which 
fee. 
RBIT, Orsira, in Afironomy, the path of a planet or 
comet ; or, sas = defcribed by its centre in its proper mo- 
tion in the heav 
e fun's, or S cihee the earth’s orbit, is the curve 
which it paffes along in its annual revolution; called the 
ecliptic. 
The orbit of the earth, and that of all the primary pla- 
s W. of Buren, in the canton of from 
ORC 
-— is an aie i one of whofe foci the fun is placed ; 
which e move according to this law, that a 
ine dra m the centre of the fun to the centre of 
the planet, always defcribes areas proportional to the 
time 
The ancient aftronomers made the planets defcribe circular 
orbits with an uniform velocity ; Copernicus himfelf could 
nd do otherwife. 
phyfics, cae made no difficulty of patel thefe circular 
orbits into elliptical ones : and of making them move with 
different besige tna in different parts of thefe orbits. 
e elliptic orbits, there have been two kinds af- 
figned ; the firft that of Kepler, which is the common el- 
lipfis 5 3 towhich Seth Ward, though he himfelf keeps to 
it, thinks one might venture to fubftitute circular orbits, by 
ufing two points, taken at equal diftances from the centre, 
on one of the pra as they do in the foci of the ellipfis. 
The fecond is that aflini, whofe character is this ; 
that the produdts of si right lines, drawn from each point 
of its circumference, are every where equal ; whereas, in the 
common ellipfis, it is e fu of thofe right lines that is al- 
ways | the fame. . Varignon fhews how inconfiftent Caper- 
nicus’s fentiment is with the mechanifm of the heavens: 
fince the forces ae L seceed have, to retain them in their 
orbits, muft alm ways confpire to make them move 
with really different qelociGes and that, among an infinity 
of cafes, there is but one in.which they can move uni- 
ly. 
S 
rm. 
The femidiameter of the earths orbit is now ftated to be 
94,696,969 miles aie and the femidiameter ef Saturn’s 
orbit about ten times as great. 
The orbits of the lactis are not all in the fame plane as 
the ecliptic, or the earth’s orbit round the fun ; but are va- 
rioufly inclined to it, and to one another : but ftill the plane 
of the ecliptic interfeéts the plane of the orbit of every 
ae in aright line, which paffes through the fun. See 
PLA 
The oe of comets Caffini takes to berectilinear ; but 
ay are now known to be very eccentric ellipfes. See 
Com 
OR RBIT ARIA Foramina, in Anatomy, two aa 
holes on the inner fide of the orbit. See Craniu 
ORBITELLO, in Geography, a town of the Siennefe, 
but belonging to Naples; fituated on the E. fide of a lake, 
near the coalt of the Mediterranean, with a good harbours 
and well fortified 5 é& miles N.W. of Rome. N. lat. 42° 
gr’. E. long. 11 
ORBONA, in Myrholgy, a goddefs worfhipped at Rome, 
who was invoked in behalf of orphans, or to comfort fathers 
and mothers for the lofs of their children. 
ORBOZ, in ihe Gea , a town of Great Bucharia, on 
the Bamian ; 15 mil Balk. 
ORBY, a town of hae in Weft Gothland; 28 miles 
E.S.E. of Gotheborg, 
HAMPS, « town of cl in the department of 
the Jura; g miles W. of Quin 
ORcCHAMPS en a a ae "of = in the depart. 
ment of the Dou i I miles rs ye Orn 
RCHAN, i graphy, of O Oiae an, the = 
of the Ottoman ak: Thinguithed for his valeu re . 
uce 
