diamagnetic 
Paramagnetics tend to move from weak to strong places 
of force while dianiagnetics tend to go from strum; to 
weak places. J. E. II. Gordon, Elect, and Mag., II. 17. 
diamagnetically (di"a-inag-net'i-kal-i), adv. 
In a diamaguetic manner ; as a diamagnetic. 
When submitted to magnetic influence, such crystals 
[bavin" one axis of figure] take up a position so that their 
optic axis points diamagneticalli/ or transversely to the 
lines of magnetic force. 
II'. R. Grove, Corr. of Forces, p. 171. 
1592 
The space between the earth and the moon, according 
to Ptolemy, is seventeen times the diameter at the earth. 
Roleiffk. 
Apparent diameter of a heavenly body. See appnr- 
s/ir.-Biparietal diameter. See biparietal. Conjugate 
diameters of a conic. See conjwjate. Ideal diameter, 
an ideal chord through the center. See ideal. la di- 
ametert t diametrically. 
He fals off again warping and warping till he come to 
contradict himselfe in diameter. 
Milton, Apology for Smectymnuus. 
diamagnetism (dl-a-mag'uet-izm), n. [= F. di- Tactical diameter, in naval tactics, the space occupied 
amaanetisme; as diamagnet-ic + -ism.'] 1. The |, y a ship in turning 180 from a straight course; the 
phenomena exh^itedY a class of ^a = *Stt&S&^&&&*fS~. 
which, -when under the influence ot magnet Tactical ( iia,,n-te vary according to the angle at which 
and freely suspended, take a position with the tnc rll( ider is held. 
longer axis at right angles to the magnetic lines diametral (di-am'e-tral), a. and n. [< F. diame- 
of force. From the experiments of Faraday it appears t r([ l = Sp. Pg. diametral = It. diametrale = D. 
to lie clearly established that all matter is subject to the (H am ctraal = Dan. Sw. diametral, < NL. "(liame- 
magnetic force as universally as it is to the gravitating ,. ,-, j. iamftra , diameter- see diameter and 
force, arranging itself into two divisions, the paramagnetic 
mttiiediamayiietic. Among the former are iron, nickel, 
cobalt, palladium, titanium, and a few other substances ; 
and among the latter are bismuth, antimony, cadmium, 
copper, gold, lead, mercury, silver, tin, zinc, and most 
solid, liquid, and gaseous substances. When a paramag- 
netic substance is suspended freely between the poles of a 
powerful horseshoe magnet, it points in a line from one 
pole to the other, which Faraday terms the axial line. 
On the other hand, when a diamagnetic substance is sus- 
pended in the same manner, it is repelled alike by both 
poles, and assumes an equatorial direction, or a direction 
at right angles to the axial line. 
The magnetism of two iron particles lying in the line 
of magnetization is increased by their mutual action, but, 
on the contrary, the diamagnetintn of two bismuth par- 
ticles lying in this direction is diminished by their mu- 
tual action. J. E. II. Gordon, Elect, and Mag., II. 21. 
If, however, the magnetism of the molecules were so 
much increased that they held each other tight, and so 
could not be turned round by ordinary magnetizing forces, 
it is shown that effects would be produced like those of 
diamagnetism. W. K. Clifford., Lectures, I. 241. 
2. That branch of magnetism which treats 
of diamagnetic phenomena and diamagnetie 
bodies. 
. 
demagnetization (di-a-mag"net-i-za shon), n. di ame tri c (dl-a-met'rik), a. 
diamagnet + -ize) + -ahon.} ca j [Rare.] " 
[< *diamac/>tetize (< 
The state of diamagnetic polarity. 
diamagnetometer (dl-a-mag-ne-tom'e-ter), n. 
[< diamaanetic + Gr. pirpov, a measure.] An 
instrument used to measure the intensity of the 
diamagnetic power of different substances. 
diamantt, A Middle English form of dia- 
mond. 
diamantiferous (di"a-man-tif'e-rus), a. [< F. 
diamantijere, < diamant, diamond (see diamond), 
+ -fere '(E. -ferous), -bearing, < L. ferre = E. 
bear 1 ."] Yielding or bearing diamonds ; produ- 
cing diamonds. 
Note on the minerals associated with the diamond in 
the newly-discovered diamantiferous district of Salobro. 
Nature, XXX. 188. 
diamantinet (dl-a-man'tin), a. [< F. diaman- 
tin = Sp. Pg. It" diamantino, adamantine: see 
adamantine and diamond.] Adamantine. 
For in the Heav'ns, aboue all reach of ours, 
He dwels immur'd in diamantine Towel's. 
Sylvester, tr. of Du Bartas's Weeks, ii., The Ark. 
tralis, < L. diametros, diameter : see diameter and 
-a/.] I. a. Pertaining to a diameter; diametri- 
cal : used especially in the physical sense. 
So diametral 
One to another, and so much opposed, 
As if I can but hold them all together, . . . 
I shall have just occasion to believe 
My wit is magisterial. 
B. Jonson, Magnetick Lady, i. 1. 
This band shall occupy a diametral position along the 
whole height of the vessel, and thus receive the friction 
the same as the walls of the tube do. 
Jour. Franklin Inst., CXXV. 41. 
Diametral circle, a circle doubly tangential to a Carte- 
sian oval on its axis of symmetry. Diametral number. 
(a) A number equal to J (1 + >/2) + >,(\ Vty 1 , where n 
is any integer. These numbers are 1, 3, 7, 17, 41, 90, etc. 
(b) A number resolvable into two factors the sum of whose 
squares is a square. Thus, 120 is such a number, because 
120 = 8 x is and 8 2 + is 2 = 17". Diametral planes, in 
crystal., those planes which are parallel to the vertical and 
one of the lateral axes ; a prism formed by such planes is 
called a diametral prism. 
II. ii. A diameter; a diagonal, 
liametrally (dl-am'e-tral-i), adv. In a diame- 
tral manner. 
Same as diametri- 
diamond-backed 
Natural crystals are found in a great variety of forms be- 
longing to the isometric system. The crystalline planes 
of the diamond have this peculiarity, that they are fre- 
quently more or less convex, instead of being Hat, as 
those of crystals usually arc. The range of color of the 
diamond is extensive, but hues of light yellow, or straw- 
color, and brown are of most common occurrence. Dia- 
monds of a decided color, such as green, blue, or even red, 
are found, but they are extremely rare ; only one deep-red 
diamond is known. A diamond is of the jirxt water when 
it is without flaw or tint of any kind. The value of the 
gem increases in an increasing ratio with its weight up to 
a moderate size ; beyond that there is no fixed value. A 
first-water diamond of one carat being considered worth 
$100, one of two carats would be held at 4800, and one of 
ten at 811,000. The most desirable form in which the dia- 
mond may be cut is called the brilliant. (See cuts under 
brilliant.) Diamonds formerly came chiefly from India, 
and later from Brazil; the present principal source of 
supply is southern Africa, where they are found associated 
with a peculiar rock of unequivocal volcanic origin. In all 
other diamantiferous regions diamonds have been found 
only in the surface detrital material (gravel and wind), or 
else, rarely, in rock of fragmental origin. See bort. 
Thei ben so harde, that no man may pollysche hem : and 
men clepen hem Dyamandei in that Contree, and Hamese 
in another Contree. Mandeville, Travels, p. 157. 
Give me the ring of mine you had at dinner ; 
Or for my diamond, the chain you promis'd. 
Shak.,C. of E.,lv. 3. 
3. A geometrical figure bounded by four equal 
straight lines forming two acute and two ob- 
tuse angles; a rhomb; a lozenge; specifically, 
such a figure printed in red on a playing-card. 
4. A playing-card stamped with one or more 
red lozenge-shaped figures. 5. A tool armed 
with a diamond, used for cutting glass. Diamonds 
so used are uncut, and they are so mounted as to act upon 
the glass, not by an angle, but by a curvilinear edge of 
the crystal. 
6. In base-ball, the square space inclosed within 
the four bases. See base-ball. 7. In her., the 
tincture black in blazoning by means of precious 
stones. See blazon, n. 8. The smallest size of 
printing-type in common use; a size smaller 
than pearl. Brilliant, very rarely used, is the 
only regular size below it. 
*ThU line U printed in diimund. 
diametrical (dl-a-met'ri-kal), a. [< Gr. dm/if- Black diamond, (a) Same as bort, 2. (6) Mineral coal, 
rpm&f, < om^erpof, diameter: see diameter."] 1. 
Of or pertaining to a diameter ; along a diam- 
eter; diametral. Prynne. 
Every portion of a current proceeding in a diametrical 
direction from the equator to the centre must progres- 
sively rise in temperature. 
H. Spencer, Universal Progress, p. 282. 
2. Pertaining to the extremities, as if of a dia- 
metrical line ; extreme in degree ; absolute ; 
utmost : as, their characters are diametrical op- 
posites. Diametrical opposition, an expression ap- 
plied by Aristotle to the extreme of opposition ; the rela- 
tion between two propositions which differ as much from 
each other as two propositions in the same terms can. 
At all events he had exposed himself to reproach by di- 
ametrical opposition to the profession of his whole life. 
Macaulay. 
diametrically (dl-a-met'ri-kal-i), adv. In a di- 
ametrical direction; directly; in an extreme 
degree. 
These Sayings seemed to clash with one another, and to 
be Diametrically opposite. Howell, Letters, ii. 17. 
The real leaders of the party . . . were men bred in 
principles diametrically opposed to Toryism. 
Macaulay, Hist. Eng., xx. 
diamesogamous (dl // a-me-sog'a-mus), a. [< 
Gr. dm, through, + fit aof, middle',' + yapos, mar- 
riage.] In bot., fertilized by the intervention 
of some external agent, as wind, water, or in- 
sects : applied to flowers. 
diameter (di-am'e-ter), n. [< ME. diametre = diamine (di;am-in) . [< Gr Si-, two-. + am- 
D. G. Dan. Sw. diameter, < OF. diametre, F. di- (moma) + -jneA] The name of a class of chemi- 
ametre =, Sp. didmetro = Pg. It. diametro, < L. cal compounds formed by substituting one or 
diametr<is,<Gr. Siautrpo^, the diagonal of a paral- ore alcohol radicals for hydrogen m a double 
lelogranj, diameter of a circle (cf . ita/ierpelv, mea- molecule made up of two ammonia molecules. 
see meter*.-] l.Ivaeom., a'chord of a circle ora ^mond^'a^mond!)' "n^nTa.^ll^E^dia- 
sphere which passes through its mcmnae dyamand, diamaunt, diamant = D. dia- 
center; in general (a) a chord of 
a conic cutting it at points tangents 
to which are parallel; (b) a line 
intersecting a quadric surface at 
points where the tangent planes 
a, Diameter of a are parallel. The conception was ex- 
circle, tended by Newton to other algebraic 
curves by means of the following theorem : 
If on each of a system of parallel chords of a curve of the 
nth order there be taken the center of mean distances of 
the n points where the chord meets the curve, the locus 
of this center is a straight line, which may be called a 
diameter of the curve. 
2. The length of a diameter ; the thickness of 
a cylindrical or spherical body as measured, in 
the former case on a diameter of a cross-sec- 
tion made perpendicular to the axis, and in the 
latter on a line passing through the center : as, 
a tree two feet in diameter ; a ball three inches 
in diameter. Inarch., the diameter of the lower face 
of the shaft of a column, divided into BO parts, fiirins a 
scale by which all the pails of a classical order are com- 
monly measured. The 60th part of the diameter is called 
a minute, and 30 minutes make a module. 
mant = MHG. diamant, diemant, G. diamant, 
demant = Dan. Sw. diamant, < OF. (and F.) di- 
amant = Pr. diaman = Sp. Pg. It. diamante 
(ML. diamantes, diamentum, MGr. dta/tavre, after 
Rom.), < L. adamas (adamant-), (1) adamant, 
(2) the diamond: see adamant. The change of 
form (in simulation of words with prefix dia-, < 
Gr. <S/d) is supposed to have been due to some 
association with It. diafano = F. diapliane, < Gr. 
SiatjiavjK, transparent: see diaphanous.'] I. . 
If. Adamant; steel, or some imaginary sub- 
stance of extreme hardness or impenetrability. 
Then zeal, whose substance is ethereal, arming in com- 
plete diamond, ascends his fiery chariot. Milton. 
2. A precious stone, distinguished from all 
others by being combustible and by its ex- 
treme hardness, as well as by its superior re- 
fractive and dispersive power. It consists of pure 
or nearly pure carbon, leaving only a very small quantity of 
ash when burned. Its specific gravity is about tt ; its crys- 
talline form is the isometric, anil it cleaves readily 'in 
planes parallel to the faces of the regular octahedron. 
, , . 
as consisting, like diamonds, of carbon. [Colloq. ] Bristol 
diamond. Same as Bristol stone (which see, under stone). 
Cornish diamonds, quartz crystals found in the tin 
mines of Cornwall. Diamond cut diamond, the case 
of an encounter between two very sharp persons. Ma- 
tura diamond, a name given in Ceylon to zircon from 
the district of Matura. Plate diamond. See the ex- 
tract. 
The cleavage of certain of the African diamonds is so 
eminent that even the heat of the hand causes some of 
them to fall in pieces. Such diamonds, generally octane- 
dra, may be recognized by a peculiar watery lustre ; they 
are called plate diamonds. Encyc. Brit., XVI. 381. 
Point diamond. See the extract. 
When the natural crystal is so perfect and clear that it 
requires only to have its natural facets polished, . . . 
jewellers call [it] a point diamond. 
Bird-wood, Indian Arts, II. 30. 
Rough diamond, a diamond uncut ; hence, a person of 
genuine worth, but rude and unpolished. Table dia- 
mond. See brilliant. 
II. a. 1. Resembling a diamond; consist- 
ing of diamonds ; set with a diamond or dia- 
monds : as, a diamond luster ; a diamond neck- 
lace ; a diamond ring. 
For all the haft twinkled with diamond sparks, 
Myriads of topaz-lights, and jacinth-work 
Of subtlest jewellery. Tennyson, Morte d'Arthur. 
2. Lozenge-shaped ; rhombic : as, diamond win- 
dow-panes. 3. Having rhomboid figures or 
markings: as, the diamond rattlesnake. Dia- 
mond cotton, a fine fabric of cotton and linen. Dia- 
mond couching. See couchingi, 6. Diamond-cut 
glass. See glas. Diamond drill. See drill. Dia- 
mond edition, an edition of a work printed in diamond, 
or in some other very small type. Diamond fret. See 
fret*. Diamond linen, a name given to various kinds 
of diaper, such as toweling, the pattern of which is in 
small lozenges. Diamond-molded glass. See glass. 
Diamond netting. See netting. Diamond pencil, a 
cutting instrument used by glaziers and glass-cutters. 
Diamond rattler, diamond rattlesnake, Crotulm 
tidauianteus. 
diamond (di'a-mond), v.t. [< diamond, .] To 
set or decorate with diamonds. 
He plays, Presses, diamonds himself, even to distinct 
shoe-buckles for a frock. Walpole, Letters, II. 241. 
diamond-back (di'a-mond-bak), . The dia- 
mond-backed turtle (which see, under dittmond- 
lni<-/:'cd). 
diamond-backed (di'a-mond-bakt), a. Having 
the back marked with lozenge-shaped figures. 
Diamond-backed turtle, .Vii/<v,', /,//* jniiiftm, a. 
tortoise of the family Clemmyidcg. The shell is keeled, 
with the shields pale yellow, and marked with brownish 
rings, which air ot'U'n'impressed ; the head and limbs are 
grayish-black, spotted and lined ; the temples are naked ; 
and the nape is covered with soft, spongy skill. It inhab- 
its the salt-water marshes of the middle and eastern At- 
lantic statei. :iinl is especially abundant in Chesapeake 
bay. This is the "terrapin" of the Philadelphia, Balti- 
