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*ards the Tefles. By this means, the BHood receives a
Check at its firift going off for thofe Parts, which difpofes it
for the future Changes, &c. it is to pafs. The fame End is
anfwered inQuadrupeds, by having thefe Arteries curl'd and
contorted in tneir Paffage like a Screw.
The Reafon why Nature has taken another Method in
Man; Mr. Co-zeper obferves, is, that in that Cafe, the Abdo-
minal Mufcles mufl have been much larger than they are ;
by which means, the Inteflines would have been frequently
let down into the Scrotum; an Inconvenience Quadrupeds
are fecured from, by the horizontal Ptofition of their Bodies.
Thefpermatic Arteries, in their Progrefs, meeting with
the fpermatic Veins, enter together with them the inner La-
mella of the Peritonurum, where, infinuating into the Du-
plicature of the Procefs, and being cloathed therewith, they
pafs on to within three or four Fingers Breadth of the
Teflicles, where they divide into Two unequal Branches,
the biggeff of which, goes to the Tefficle, and is difiributed
therein (See TESTICLE.) And the lefs in the P1aralata or
.Epididydimis. See PARASTATA.
The fpermatic Veins take the fame Courfe with the Ar-
teries; only a little above the Tefficles, they fplit into fe-
veral Branches, which uniting, form a Plexus, called Corpus
Varicofum  Pampiniforme or Pyramidale. The Blood re-
turned by the fpermatic Veins, is delivered on the right Side
to the Cava, and on the Left, into the emulgent Vein.
SPERMATOCELE, in Medicine, a Rupture occafioned
by a Contradion of the feminal Vefels, whereby they are let
fall into the Scrotum. Harris.
SPHACELUS, in Medicine, a total Mortification of any
Part, occafioned by an Interception of the Blood and Spirits.
See MORTIFICATION.
The Word is Greek, v4X'Xsx@a, fortm'd, perhaps, of a¢dTJWj
I kill.
The Sphacelus is diftinguifhed from the Gangrene; which
is only a Mortification begun, and, as it were, the Road to a
Sphacelus, which is the State and Perfeaion thereof. See
GANGRENE.
The Sphacelus is diflinguiflied by the Lividnefs or Black-
nefs of the Part affeded; its Softnefs, Infenfibility and ca-
daverous Smell.
The other Caufes of the Sphacelus, are clofe Ligatures,
cxceffive Colds, great Inflammations, Bites of Mad Dogs.
'Tis Sometimes, alfo, called Necrofis, and Sometimes Sidera-
tio. See NECROSIS and SIDERATIO.
A Sphacelous Foot, according to Aquapendente, ought to be
cut off in the mortified Part, near the live Part. When the
Foot is off, the dead Flelh left behind, is to be confumed
by the Application of an a~lual Cautery, repeated feveral
Times, till the Patient feel the Heat of the Fire. Scultet.
SPH1ERISTERIUM, in Antiquity, the feventh Part of
the ancient Gymnafium; being that wherein the Youth prafti-
fid Tennis-Playing. See GYMNASIUM.
The Spherizferium or Tennis-Court, was between the
Place, named Palel:fra, and that where they run Races,
which was between the Portico's and the outer Wall : Though
Titruvius does not make mention of it in the Defcription
he gives of the ancient Gymnafium.
The Exercife here perform'd was called Spherifc and
Spheromachia, which fbme will have to have differ'd from
the modern Tennis 5 but 'tis not known wherein the Diffe-
rence confifled.
The Milefjans were particularly averfe to this Exercife;
and the Athenians as remarkably fond of it.
They frequently gave the Right of Citizens to the Sphe-
rifes, or Matters in this Art, by way of Refpect.
SPHENOIDAL Suture, in Anatomy, a Suture thus call'd,
from its encompafling the Os Sphenoides, which it Separates
from the Os frontis, the Ospetroflum and Os occipitis. See
SUTURE.
SPHENOIDES, in Anatomy, a Bone of the Head, com-
mon to the Craniumand upper Jaw. See CRANIUM, eGC
It is fituate in the lower Part of the Skull, whereof it is,
as it were, the Bafis, and is conneled to all the other Men-
bers thereof, by the SphenoidalSuture. Its Form, is irregu-
lar, and not eafy to be described; whence fome have call'd
it Multiforme. It has its Name SPhenoides from the Greek,
eoar, Cuneus, Wedge,from the Form of its Infertion into the
other Bones of the Skull.
In Adults, 'tis one continued Bone; but in young Children,
Sometimes confills of Thrce, and fomr.imes of Four difin&
Pieces.
SPHENOSTAPHYLINUS, in Anatomy, a Mufcle of
kthe Larynx. It defcends from a round, flefhy Origination,
near the Root of a Procefs of the Os Sphenoides, and is im-
planted into the poflerior Part of the Uvula, where it joins
its Partner. It ferves to draw the Uvula upwards and back-
wards; and hinders the muafticated Aliment from paffing into
the Foramina Narium in Deglutition.
SPHERE, in Geometry, a Solid Body contained under
One fingle Surface, and having a Point in the middle, call'd
.the Centre, whence all the Lines drawn to the Surface, are
equal. See SOLID, SfC.


S91 H


The Sphe)re is fuppofed to bq generated by the Revolutior
of a Semi-circle, as K, (Tab. Geometry Fig. 34.) about itO
Diameter A B, which is alfo called the Axis of the Sphere,
and the extreme Points of the Axis, A and C the Poles of
the Sphere. See CENTRE, CIRCUMFERENCE, Axis, POLE,
&c.
Properties of the SPnERre.
10 A Sphere is equal to a Pyramid, whofe Bafe is @qual
to the Surface, and its Height to the Radius of the Shere.
Hence a Sphere being efteem'd fiuch a Pyramid, its Cube
or Solid Content, is found like that of a Pyramid. See
PYRAMID.
20 A Sphere is to a Cylinder, flanding on an equal Bafis,
and of the fame Height, as2 to 3. Hence, allo, may the Cube
or Content of the Sphere be found. See CYLINDER.
3f The Cube of the Diameter of a Sphere, is to the Solid
Content of the Sphere, nearly as 300to 157  And thus, alto,
may the Content of the Sphere be meafured.
40 The Surface of a Sphere is quadruple that of a Circle
described with the Radius of the Sphere. For fince a Sphere
is equal to a Pyramid, whofe Bafe is the Surface, anditsAlti-
tude, the Radius of the Sphere: The Surface of the Sphere
is had, by dividing its Solidity by a third Part of its Semi-
diameter.
If, now, the Diameter of the Circle be Ioo, the Area
will be 7850; consequently, the Solidity 1570000, which
divided by a Third of the Semi-diameter, Ioo; the Quo-
tient is the Surface of the Sphere 31400 ; which is manifeftly
quadruple the Area of the Circle.
The lDiameter of a SPHERE being given, to find its Surface
and Solidity.
Find the Periphery of the Circle described by the Radids
of the Sphere. See PERIrHERY.
Multiply this, found, into the Diameter; the Produat is
the Surface of the Sphere. Multiply the Surface by a fixth
Part of the Diameter, the Produd is the Solidity of th6
Sphere.
Thus, fuppofing the iiameter of the Sphereq6, the Peri-
phery will be found I1 7; which multiplied by the Diametet,
the Produ&i 9800 is the Surface of the Sphere; which mul-
tiplied by one fixth Part of the Diameter, gives the Solidity
91905. Or, thus;
Find the Cube of the Diameter 175616 i then to 300157,
and the Cube found, find a Fourth proportional, 9 IgoS7
See PROPORTIONAL. This is the Solidity of the Sphere
required.
For Segments and Sear's of Spheres; lee SEGMENT and
SECTOR.
SDoarine of the SPHERE    Se   SPHERICKS.
Projefion of the SPHERE }      PROJECTION.
SPHERE of Allivity of any Body; is that determinate
Space or Extent, all round about it, to which, and no farther,
the Effluvia continually emitted from that Body, do reach,
and where they operate according to their Nature. See
EFFLUVI A.
Thus we fee the magnetical Effluvia have certain Bounds
and Limits, beyond which they will have no Influence to turn,
orattradt the Needle: But where.ever a Needle is placed, to
as it may be moved by a Load-flone, it may be faid to be
within the Sphere of Affivity of the Stone. See MAGNaeT.
SPHERE, in Aftronomy, that concave Orb or Expanfe,
which invefis our Globe, and in which the heavenly Bodies,
Sun, Stars, Planets and Comets, appear to be fix'd, at equal
Diffances from the Eye. See HEAVENS.
This is alto call'd the Sphere of the World; and is the
Subject of the Spherical Afironomy.    See SPHERICAL
A4ftronomy.
This Sphere, as it includes the fix'd Stars, whence we alfo
occasionally call it, the Sphere of the fix'd Stars, is vaily
great. The Diameter of the Earth's Orbit is 1o fimall, in
refpe&k of the Diameter hereof, that the Centre of the
Sphere is not fenfibly changed by any Alteration of the
Speffator's Place in the feveral Parts of the Orbit: But fill,
in all the Points of the Earth's Surface, and at all Times,
the Inhabitants have the fame Appearance of the Spheie;
that is, the fix'd Stars feem to poffefs the fame Points in the
Surface of the Sphere. For our Way of judging of the
Places, Fic. of the Stars, is to conceive right Lines drawn
from the Eye or the Centre of the Eafth, through the Centres
of the Stars, and continued thence, till they cut the forefaid
Sphere; the Points where thele Lines terminate therein, are
the apparent Places of thofe Stars. See PLACE andPARALLAX.
The better to determine the Places of the heavenly Bodies
in the Sphere; feveral Circles are imagined to be defcribed
in the Surface thereof; hence called Circlesof theSpbere.
See CIRCLE of the Sphere.


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