spherical 
.- Spherical lune, the portion of the surface of 
ttphere included between two great circles. Spherical 
nucleus. Same as mtcli'ux ffuboatu (which see, undn- 
nucleus). Spherical pencil, a singly infinite continuous 
series of spheres determined like a spherical Kroup, but 
by three equations. Spherical polygon. Sec polygon. 
Spherical representation, a mode of continuous corre- 
spondence between the points of a surface and the points 
of a sphere, each radius of the sphere through the center 
representing the parallel normal of the surface. Any part 
of the sphere considered as thus representing a part of the 
surface is called its spherical I'M aye. Spherical saw, 
a saw made in the form of a segment of a sphere, used for 
sawing out curvilinear work. See cut d under 0au?l. 
Spherical sclere. See sclere and spheraster. Spheri- 
cal-shot machine, a machine for finishing cannon-balls 
by molding and pressing to a true spherical form. E. II. 
Knvjh t. Spherical surface-harmonic. See harmonic. 
Spherical triangle, trigonometry, etc. See the 
nouns. 
sphericality (sfer-i-kal'i-ti), H. [< spherical + 
-i/i/.] Spherical form ; sphericity. N.A.fiei'., 
CXXVI. 375. [Rare.] 
spherically (sfer'i-kal-i), adv. In the form of 
a sphere, or of part of a sphere ; so as to be 
spherical. 
sphericalness (sfer'i-kal-nes), H. The state or 
-,...- .., j being in 
shape of a sphere. 
sphericle (st'er'i-kl), w. [Dim. of sphere.] A 
small sphere ; a spherule. [Rare.] Imp. Diet. 
spherics (sfer'iks), n. [PI. of spheric (see -ies).] 
Geometry of figures drawn on the surface of a 
sphere; specifically, spherical trigonometry. 
spheriform (sfe'ri-form), a. [< L. sphxra, 
sphere, + forma, form.] Formed or existing 
as a sphere ; sphere-shaped ; spherical. Cud- 
worth, Intellectual System, II. 23. [Rare.] 
spherocobaltite (sfe-ro-ko'bal-tit), . [< Gr. 
a<paipa, a ball, sphere, + E. cobalt + -ite?.] Carbo- 
nate of cobalt, a rare mineral occurring in small 
spherical masses with concentric radiated struc- 
ture, and having a peach-blossom red color. 
spheroconic (sfe-ro-kon'ik), n. [< Gr. atjxupa, a 
ball, sphere, + auvof, a cone: see conic.] A 
non-plane curve, the intersection of a sphere 
with a quadric cone having its vertex at the 
center of the sphere Cyclic arcs of the sphero- 
conic, the intersections of the cyclic planes of the cone 
with the sphere. Reciprocal spheroconic, the envelop 
of the great circles of which the points on the first sphero- 
conic are the poles. 
spherocrystal (sfe-ro-kris'tal), H. [< Gr. a<t>aipa, 
a ball, sphere, + Kpi-araUaf, crystal.] 1. In 
lithol., a mineral occurring in spherical form 
with fibrous-radiate structure. 2. pi. In hot., 
same as sphxraphides. 
spherodactyl (sfe-ro-dak'til), a. Of or per- 
taining to the genus Nphaerodactylus, as a gecko. 
spherogastric (sfe-ro-gas'trik), a. [< Gr. a$alpa, 
a ball, sphere, + yaarf/p, stomach.] Having a 
spherical or globular abdomen, as a spider; of 
or pertaining to the Spheeroi/astra. See cut 
under honey-bearer. 
spherograph (sfe'ro-graf), n. [< Gr. oQaipa, a 
ball, sphere, -t- ypfyeiv, write.] A nautical in- 
strument consisting of a stereographic projec- 
tion of the sphere upon a disk of pasteboard, 
in which the meridians and parallels of latitude 
are laid down to single degrees. By the aid of this 
projection, and a ruler and index, the angular position of 
a ship at any place, and the distance sailed, may be read- 
ily and accurately determined on the principle of great- 
circle sailing. 
spheroid (sfe'roid), ii. [Also spliseroid; = F. 
splieroide, < Gr. mfiaipoeiStif, like a ball or sphere, 
globular, < afyalpa, a ball, sphere, + fMof, form.] 
1. A geometrical body approaching to a sphere, 
but not perfectly spherical. 2. In geom., a 
solid generated by the revolution of an ellipse 
about one of its axes. When the generating ellipse 
revolves about its longer or major axis, the spheroid is 
prolate or oblong ; when about its less or minor axis, the 
spheroid is oblate. The earth is an oblate spheroid that 
is, flattened at the poles, so that its polar diameter is 
shorter than its equatorial diameter. (See earthl, 1.) The 
same figure is assumed by the other planets ; hence the 
properties of the oblate spheroid are of great importance 
in geodesy and astronomy. Universal spheroid, a sur- 
face generated by the revolution of an ellipse about any 
diameter. 
spheroidal (sfe-roi'dal), a. [< spheroid + -al.] 
1 . Of or pertaining to, or having the form of, 
a spheroid. 2. In crystal., globose; bounded 
by several convex faces. 3. In entom., round 
and prominent, appearing like a ball or sphere 
partly buried in the surface : as, spheroidal 
eyes; spheroidal coxie.- Spheroidal bracketing, 
in arch., bracketing which has a spheroidal surface 
Spheroidal epithelium. See epithelium. Spheroidal 
state or condition, the condition of water or other li- 
quid when, on being placed on a highly heated surface, 
as red-hot metal, it assumes the form of a more or less 
flattened spheroid, and evaporates without ebullition. 
5826 
The spheroid in this condition does not touch the surface 
of the metal, but floats on a layer of its own vapor, and 
evaporates rapidly from its exposed surface. It is bcaU-d 
mainly by radiation from the hot surface, since the layer 
of intervening vapor conducts heat very feebly. The 
formation of a layer of non-conducting vapor explains why 
it is possible to dip the wetted hand ink) molten iron with 
impunity. It is sometimes spoken of as the caloric or 
calorific paradox. 
SphefoidaHy(sfe-roi'dal-i), ailc. In a spheroidal 
manner: so as to form a spheroid or spheroids. 
The great mass ... is largely built up of spheroidaUy 
jointed rock. Quart. Jour. deal. Soc., XLIV. 460. 
spheroidic (sfe-roi'dik), a. [=F.spltr : i'<itili</u<-; 
us spheroid + -ic.~\ Same as spheroidal. [Rare.] 
spheroidical (sfe-roi'di-kal), . [< spheroidic 
+ -a?.~\ Same as spheroidal. [The usual old 
form.] 
The same spheroidical form. 
Jefferson, Correspondence, II. 67. 
spheroidicity (sfe-roi-dis'i-ti), H. [<sphcniiilii' 
+ -ity.] The state or character of being sphe- 
roidal. 
Spheroma, . See Sphferonm. 
spheromere (sfe'ro-mer), w. [Also sphseromere; 
< Gr. aifaipa, a ball, sphere, + fupof, a part.] 
One of the radially arrangeol parts or sym- 
metrical segments of any radiate ; an actino- 
mere. Perhaps the most remarkable spheromeres are 
those two which, In the Venus's-girdle, give that ctenoph- 
oran a ribbon-like figure by their enormous development. 
See cut under Cesium. 
spherometer (sfe-rom'e-ter), . [< Gr. otyaipa, 
a ball, sphere, + [tfrpov, measure.] An instru- 
ment for measuring the 
radii of spheres; a 
sphere-measurer, it is of 
especial service to opticians in 
determining the focal lengths, 
etc., of lenses. The common 
form (see figure) consists of a 
vertical screw c, with a large 
graduated head a a, turning 
in a socket supported by three 
legs whose hard steel points 
are exactly equidistant. The 
fixed scale b at the side, toge- 
ther with thegraduated screw- 
head, makes it possible to mea- 
sure with great accuracy the spherometer. 
distance between the extrem- 
ity of the screw and the plane passing through the ends 
of the three supports, when, for example, all the points 
are in contact with the surface of the sphere. If, in ad- 
dition, the distance between the ends of the supports 
is known, a simple calculation gives the radius of the 
sphere. The same instrument may also be used to deter- 
mine with precision the thickness of a plate, as (in the 
figure) A, placed upon a horizontal surface. 
spheromian (sfe-ro'mi-an), a. and w. [< Sphe- 
roma + -tan."] I. a. Of or pertaining to Sphse- 
roma or the Sphseromidee. 
II. ii. A globe-slater. 
Also spelled sphseromian. 
spheropolar (sfe-ro-po'lar), . [< Gr. a^alpa, 
sphere, + E. polar.] Reciprocal relatively to 
a sphere. The plane through the points of contact of 
a cone with a sphere is the spheropolar of the vertex. 
spherosiderite (sfe-ro-sid'e-rit), . [Also 
sphaerosiderite ; < Gr. a</xiipa, a ball, sphere, + 
<7%>m7f, of iron: see siderite.] A variety of 
the iron carbonate siderite, occurring in globu- 
lar concretionary forms. 
spherospore (sfe'ro-spor), n. [< Gr. oQaipa, a 
ball, + E. spore.] In bot., same as tetraspore. 
spherular (sfer'Q-lar), a. [< spherule + -ar$.] 
1 . Having the form of a spherule ; resembling a 
spherule. 2. Of or pertaining to a sphemlite; 
spherulitic. 
Spherular bodies consisting of radially-aggregated fibres 
of a single mineral. Nature, XXXIX. 315. 
spherulate (sfer'o-lat), . [< spherule + -ate 1 .] 
In entom., having one or more rows of minute 
rounded tubercles ; studded with spherules. 
spherule (sfer'6'1), n. [Also sphserulf ; < L. 
sphsrula, dim. of sph&ra, a ball, sphere : see 
sphere.] A little sphere or spherical body. 
Quicksilver, when poured upon a plane surface, divides 
itself into a great number of minute spherules. 
spherulite (sfer'o-lit), n. [Also sphaerulite; < 
spherule + -ite 2 .] 1. A vitreous globule, such 
as those of which perlite is made up, having a 
more or less perfectly developed concentric and 
at the same time decidedly radiating fibrous 
structure. The highly silicious volcanic rocks 
not unfrequently have a spherulitic structure. 
2. Same as radiolite, 2 Spherulite rock, in 
geol., a rock of which the predominating part has a spheru- 
litic structure. 
spherulitic (sfer-p-lit'ik), a, [< spherulite + 
-ic.] Made up of or containing spherulites ; 
having the character of a spherulite. Also 
sphserulitic. 
spherulitize (sfer'o-li-tiz), v. t. ; pret. and pp. 
sphcruHtized, ppr. spherulitizing. [< spherulite 
Sphindidae 
+ -i:c.] To convert more or less completely 
into spherulites, or cause to assume a spheru- 
litic structure, wholly or in part. Quart. .Innr. 
i;'i. soe., XLV. ivi. 
spherulitoid (sfer'i>-li-toid), . [< spherulite + 
-OK/.] Having more or less perfectly the form of 
a spherulite. tjuart. .four. Geol. Soc., XLV. 248. 
sphery (sfer'i), a. [< sphere + -i/ 1 .] 1. Be- 
longing to the spheres. 
She can teach ye how to climb 
Higher than the x]iher>/ chime. 
Milton, Comus, 1. 1021. 
2. Resembling a sphere or star in roundness, 
brightness, or other attribute. 
What wicked and dissembling glass of mine 
Made me compare with Henuia's sphery eyne? 
Shak., M. >'. U, ii. 2. 99. 
spheterize(sfet'e-riz), v. t. ; pret. and pp. spin /- 
i ri.:<-d, ppr. spheterizing. [< Gr. oQeTe/iiCen; 
make one's own, < o0/rrpoc, their own, poss. adj. 
of the 3d pers. pi., < o-^rif, they.] To take to 
one's self; appropriate as one's own. Burke. 
[Rare.] (Encyc. Diet.) 
Sphex (sfeks), n. [NL. fi,innfeus, 1758), < Gr. 
op'/f, a wasp: see wasp.] 1. A notable genus 
of large handsome digger-wasps, typical of the 
family Sphegidse (or Sphecidee orSpht-xidse). They 
abound in tropical regions, but some 12 species inhabit 
the United States. S. ichneujnonea digs rapidly in hard 
ground, and provisions its cells with grasshoppers. About 
100 species are known. See cut under digger-wasp. 
2. [/. c.] A wasp of this genus. 
sphex-fly ( sfeks'fll), n. One of numerous differ- 
ent dipterous insects, as of the genus Conops, 
which resemble a sphex in some respects. 
sphiggure (sfig'ur), . See uphi n</iire. 
sphincter (sfingk'ter), H. [NL., < L. sphincter, 
< Gr. a<t>r,KTf/p, anything which binds tight, 
a lace, a band ? < offyyeo', shut tight, close.] 
An orbicular, circular, or annular muscle sur- 
rounding and capable of closing a natural 
orifice or passage of the body Oral sphincter. 
Same as orbicularis oris (which see, under orbiculari*). 
Sphincter ani, the sphincter of the anus, underwhich 
name two distinct muscles are known, (a) The sphincter 
ani proper, sphincter externus, or external sphincter is a 
thin, flat plane of voluntary muscular fibers supplied by 
hemorrholdal branches of nerves from the sacral plexus, 
surrounding the anus, subcutaneous and intimately adher- 
ent to the Integument, of elliptical form 3 or 4 inches in 
long diameter, and an inch wide across. It arises from the 
tip of the coccyx, and is inserted into the tendinous raphe 
of the perineum. Like most sphincters, it consists of sym- 
metrical lateral halves united by a raphe in front of and 
behind the opening it incloses, (b) The sphincter recti, 
sphincter internus, or internal sphincter tmrroundg the 
lower end of the rectum, forming a muscular ring about an 
inch in extent and a quarter of an inch thick, and consists 
of an aggregation and thickening of the circular fibers of 
the gut. This sphincter is involuntary, and in health main- 
tains its tonic contractility, which yields by reflex action 
to the pressure of the contents of the bowel. Sphincter 
oculi, or sphincter palpebrarum, the orbicular muscle 
of the eyelids, which surrounds and closes them. Usually 
called orbicularis palpebrarum. See cut under muscle*. 
Sphincter oris. the oral sphincter. See orbicularis oris, 
under orbicularis. Sphincter pupillaris, the circular 
or concentric fibers of the iris, wnose contraction makes 
the pupil smaller. Also called sphincter pupillff and 
sphincter iridis. Sphincter pylori. See pylorvs. 
Sphincter recti, the internal sphincter ani (see above). 
Sphincter vaginae, an elliptical muscle surrounding 
the orifice of the vagina, corresponding to the bulboca- 
vernosus of the male. Also called constrictor vaginst. 
Sphincter vesicSB, the unstriped involuntary muscular 
fibers around the neck of the urinary bladder. Sphinc- 
ter vesicffl externus, the partly plain partly striated 
muscular fibers which surround the prostatic part of the 
urethra. Also called sphincter progtaticus and sphincter 
of Henle. 
sphincteral (sfingk'ter-al), a. [< sphincter + 
-al.] Same as sphincterial. 
sphincterate (sfingk'ter-St), a. [Also sphinc- 
trate. < sphincter + -ate 1 .] 1. Ina/. and2oo7., 
provided with a sphincter; closed or closable 
by means of a sphincter. 2. Contracted or 
constricted as if by a sphincter: thus, an hour- 
glass is sphincterate in the middle. 
sphincterial (sfingk-te'ri-al), a. [< sphincter 
+ -ial.] Of or pertaining to a sphincter or its 
function : as, a sphincterial muscle ; sphincte- 
rial fibers ; sphincterial action. 
sphincteric (sfingk-ter'ik), a. [< sphincter + 
-ic.] Same as Kphincterial. 
sphincterotomy (sfingk-te-rot'o-mi), w. [< Gr. 
O(fiiyK7>ip, a sphincter, + -rouia, < rt/iveiv, TO/JCIV, 
cut.] The operation of cutting a sphincter to 
prevent its spasmodic action. 
sphinctrate (sfingk'trat), a. Same as sjihinc- 
terate. 
Sphindidae (sfin'di-de), n. pi. [NL., < Sphin- 
dus + -idle.] An aberrant family of serncorn 
beetles, in which the antenna} are so obviously 
clayate as to resemble those of the clavicorn 
series. It contains a few small species found in fungi 
which grow upon the trunks of trees. 
