developable 
2. In geom., reducible to a plane by bending: 
applied to a particular species of ruled surface, 
otherwise called a torse, which is conceived as 
formed by an infinite succession of straight 
lines, each intersecting the next Developable 
lielicoicl. See heticoid. 
II. n. In geom. , a singly infinite continuous 
succession of straight lines, each intersecting 
the next ; a torse. The word developable is used as a 
noun by modern geometers, because they do not consider 
this locus to be properly a surface. It is rather a skew 
curve regarded under a particular aspect. A developable 
is generated by a line which turns about a point in itself, 
while this point moves along the line. The locus of the 
point is a skew curve, called the edge of regression of the 
developable, to which the line is constantly tangent. The 
developable is thus the locus of tangents of a skew curve. 
Considering the osculating plane at any fixed point of this 
curve, the moving tangent conies up to this plane so that 
for an instant its motion is in the plane and then passes 
off ; and the result is that the curve is a cuspidal edge of 
the developable considered as a surface. Polar devel- 
opable of a skew curve, the surface enveloped by its 
normal planes. The locus of the center of curvature of 
the skew curve is the edge of regression, while the axis 
of curvature is the generator of the polar developable. 
developed (df-vel'upt), p. a. [Pp. of develop, v.~\ 
1. Unfolded ;' laid open ; disclosed. 2. In her., 
same as disveloped. 
developer (de-vel'up-er), n. One who or that 
which develops or unfolds. 
The first developers of jury trial out of the different pro- 
cesses and judicial customs which various races and rulers 
had imported into this island, or had created here. 
Sir E. Creasy, Eng. Const. 
Specifically, in photog. , the chemical bath in which a sensi- 
tized plate or paper is, after a photographic exposure to 
the light, immersed to develop or bring out the latent 
image. Developers for the ordinary dry-plate process may 
be divided into two principal classes, alkaline developers 
and ferroui-oxalate developers, the first generally employ- 
ing carbonate of soda or potash in combination with pyro- 
gallic acid, and the second using oxalate of potash with 
protosulphate of iron. The results obtained are practi- 
cally the same with either bath, the latent image in the 
film being made visible, and the chemical changes induced 
being fixed, or made permanent in the fixing bath, which 
follows the developing bath. Many other chemicals may 
be used in development, either in combination with some 
of those mentioned above or in independent combina- 
tions. See photography. 
M. Balagny claims "that with this chemical he has de- 
veloped plates without fog in such a light as would have 
been impossible . . . with other known developers." 
Philadelphia Ledger, Feb. 28, 1888. 
development (de-verup-ment), n. [Also de- 
velopement; < F. dtoeloppement, < developper, de- 
velop: see develop and -went.] 1. A gradual 
unfolding; a full disclosure or working out of 
the detafls of something, as the plot of a novel 
or a drama, an architectural or a military plan, 
a financial scheme, etc. ; the act of evolving or 
unraveling. 2. The internal or subjective pro- 
cess of unfolding or expanding; the coming 
forth or into existence of additional elements, 
principles, or substances; gradual advancement 
through progressive changes ; a growing out or 
up; growth in general: as, the development of 
the mind or body, or of a form of government ; 
the development of the principles of art or of 
civilization. 
A new development of imagination, taste, and poetry. 
Channing. 
But this word development . . . implies not only out- 
ward circumstances to educate, but a special germ to be 
educated. J. F. Clarke, Ten Great Religions, i. 7. 
Specifically 3. In biol., the same as evolution : 
applied alike to an evolutionary process and its 
result. 
Development, then, is a process of differentiation by 
which the primitively similar parts of the living body be- 
come more and more unlike one another. 
Huxley, Anat. Invert., p. 20. 
4. In math.: (a) The expression of any function 
in the form of a series; also, the process by 
which any mathematical expression is changed 
into another of equivalent value or meaning 
and of more expanded form; also, the series 
resulting from such a process. (6) The bend- 
ing of a surface into a plane, or of all its in- 
finitesimal parts into parts of a plane, (c) 
The bending of a non-plane curve into a plane 
curve. 5. In photog., the process by which 
the latent image in a photographically exposed 
sensitive film is rendered visible through a 
chemical precipitation on that portion of the 
sensitized surface which has been acted on by 
light. The matter deposited varies with the nature of 
the process. In the daguerreotype process it is mercury ; 
in negative processes with salts of silver it is silver com- 
bined with organic matter. 
6. In music: (a) The systematic unfolding, by 
a varied rhythmic, melodic, or harmonic treat- 
ment, of the qualities of a theme, especially in 
a formal composition like a sonata. (b) That 
1578 
part of a movement in which such an unfolding 
of a theme takes place Alkaline development. 
See alkaline. Binomial development. See binomial. 
Theory of development. () In theul. , the theory that 
man's conception of his relations to the infinite is progres- 
sive but never complete. (b) In biol., the theory of evolu- 
tion (which see, nnAer evolution). = Syn. 1. Unraveling, dis- 
entanglement. 3. Growth, evolution, progress, ripening, 
developmental (de-vel'up-men-tal), a. [< de- 
velopment + -?.] ' 1. Pertaining to develop- 
ment; formed or characterized by develop- 
ment: as, the developmental power of a germ. 
For, while the plant had first to prepare the pabulum 
for its developmental operations, the animal has this al- 
ready provided for it. 
H'. B. Carpenter, in Grove's Corr. of Forces, p. 421. 
2. In biol., the same as evolutionary. 
The Greek nose, with its elevated bridge, coincides not 
only with resthetic beauty, but with developmental per- 
fection. E. D. Cope, Origin of the Fittest, p. 148. 
developmentally (de-vel'up-men-tal-i), adv. 
In a developmental manner; by means of or 
in accordance with the principles of the de- 
velopment theory; as regards development. 
I conceive then that the base of the skull maybe demon- 
strated developmentally to be its relatively fixed part, the 
roof and sides being relatively moveable. 
Huxley, Man's Place in Nature, p. 171. 
developmentist (de-vel'up-men-tist), n. [< de- 
velopmen t + -ist.~\ 'One who holds or favors the 
doctrine of development ; an evolutionist. 
The assumption among religious developwentists is that 
we cannot have the artistic and literary progress without 
an increased complication of creeds and dogmas, but to 
that I distinctly demur. 
J. Owen, Evenings with Skeptics, II. 220. 
devemistatet, v. t. [< LL. devenustatus, pp. of 
dei'enustare, disfigure, deform, < L. de- priv. + 
LL. venustare, make beautiful, < L. venustus, 
beautiful, < Venus, the goddess of love and 
beauty: see Venus.'] To deprive of beauty or 
grace. 
Of beauty and order devenustated, and exposed to shame 
and dishonour. 
Waterhouse, Apol. for Learning (1653), p. 245. 
devert, n. [Early mod. E. also devour, < ME. 
dever, < AF. * dever, OF. deveir, devoir, F. devoir, 
debt, duty, homage, < deveir, devoir, F. devoir 
= Pr. dever = Sp. Pg. deber = It. devere, owe, 
< L. debere, owe: see debt, debit, and cf. devoir, 
a mod. form of dever. Hence endeavor, q. v.] 
Duty; obligation. 
Than seide the kynge Carados, "I wote not what eche 
of yow will do ; but as for me, I will go hym a-geyns, and 
yef I haue nede of socour and helpe, so do ye youre dever." 
Merlin (E. E. T. S.), ii. 162. 
devergence, devergency (de-ver'jens, -jen-si), 
. Same as divergence, divergency. [Bare.] 
deversoir (de-ver'swor), n. [< F. deversoir, < 
d6verser, lean, bend, < devers, bent, curved, < 
L. deversus, pp. of devertere, turn away, < de, 
away, + vertere, turn: see verse.'} In hydraul. 
engin., the fall of a dike. E. H. Knight. 
devest (de-vest'), v. [= OF. devestir, F. devetlr 
= Pr. devestir, desvestir = It. divestire, < L. de- 
vestire (ML. also divestire), undress, < de- (or 
dis-) priv. + vestire, dress, < vestis, dress, gar- 
ment: see vent. Cf. divest, the more common 
form.] I. trans. If. To remove vesture from ; 
undress. 
Like bride and groom 
Devesting them for bed. Shak., Othello, 11. 3. 
2f. To divest; strip; free. 
Then of his arms Androgeus he devests, 
His sword, his shield he takes, and plumed crests. 
Sir J. Denham. 
Come on, thou little inmate of this breast, 
Which for thy sake from passions I devest. Prior. 
3. In law, to alienate ; annul, as title or right ; 
deprive of title. 
What are those breaches of the law of nature and na- 
tions which do forfeit and devest all right and title in a 
nation to government? Bacon. 
The rescinding act of 1796 . . . could not devest the 
rights acquired under . . . [previous] contract. 
Chief-Justice Marshall, quoted in H. Adams's Randolph, 
[p. 106. 
II. in trans. In law, to be lost or alienated, as 
a title or an estate. 
devext (de-veks'), a. and n. [< L. devexus, slop- 
ing, shelving, orig. another form of devectus, pp. 
otdevehere, carry down; passive in middle sense, 
go down, descend; < de, down, + vehere, carry : 
see vehicle, vex.~] I. a. Bending down. 
Thai love lande devexe and inclinate. 
Palladium, Husboudrie (E. E. T. S.), p. 94. 
II. . Same as devexity. 
Following the world's dcvex, he meant to tread, 
To compass both the poles, and drink Nile's head. 
May, tr. of Lucan's Pharsalia, x. 
deviator 
Devexat (de-yek'sft), n. pi. [NL., neut. pi. of L. 
devexus, sloping, steep (see devex) ; in allusion 
to the great stature and sloping neck of the gi- 
raffe.] A family of ruminants, of which the 
giraffe is the only living representative. See 
Giraffidie. Illiyer. 
devexityt (de-vek'si-ti), n. [< L. derexitii(t-)s, 
< devexus, sloping: 'see devex."] A bending or 
sloping down; incurvation downward. Also 
devex. 
That heaven's divexity [devexity]. 
Sir J. Dairies, Witte's Pilgrimage, sig. N i. b. 
deviantt (de'vi-ant), a. [ME. dei'iaunt, < OF. 
deviant, < LL. deiian(t-)s, ppr. of deviare, de- 
viate: see deviate.'] Deviating; straying; wan- 
dering. Mom. of the Hose. 
deviate (de'vi-at), v. ; pret. and pp. deviated, 
ppr. deviating. [< LL. deviatus, pp. of deviare 
(> It. deviare = Sp. desviar = Pg. deviar, desviar 
= OF. devier, desvier), go out of the way, < L. de- 
vius, out of the iway : see devious.'] I. intrans. 
1. To turn aside or wander from the way or 
course ; err ; swerve : as, to deviate from the 
common track or path, or from a true course. 
What makes all physical or moral ill ? 
There deviates nature and here wanders will. 
Pope, Essay on Man, iv. 112. 
2. To take a different course ; diverge ; differ. 
He writes of times with respect to which almost every 
other writer has been in the wrong ; and, therefore, by 
resolutely deviating from his predecessors, he is often in 
the right. Macaulay, Mitford's Hist. Greece. 
Deviating force. See force. =Syn. To stray, digress, de- 
part, diverge, vary. 
II. trans. If. To cause to swerve ; lead astray. 
A wise man ought not so much to give the reins to hu- 
man passions as to let them deviate him from the right 
path. Cotton, tr. of Montaigne, xxxv. 
2. To change the direction or position of, as a 
ray of light or the plane of polarization. See 
biquartz. 
deviation (de-vi-a'shon), n. [= F. deviation 
= Sp. deviacion, desviacion = Pg. deviafSo = It. 
deviazione, < ML. deviatio(n-), < LL. deviare, 
deviate: see deviate.'] 1. The act of deviat- 
ing ; a turning aside from the way or course. 
These bodies constantly move round in the same tracts, 
without making the least deviation. Cheyne. 
2. Departure from a certain standard or from 
a rule of conduct, an original plan, etc. ; varia- 
tion ; specifically, obliquity of conduct. 
Having once surveyed the true and proper natural al- 
phabet, we may easily discover the deviations from it. 
Holder. 
The least deviation from the rules of honour introduces 
a. train of numberless evils. Steele, Tatler, No. 251. 
3. In com., the voluntary departure of a ship 
without necessity, or without reasonable cause, 
from the regular and usual course of the spe- 
cific voyage insured. In the law of insurance it in- 
cludes unreasonable delay on the voyage, as well as be- 
ginning an entirely different voyage. 
4. In astron., the oscillatory motion of a plane ; 
especially, in the Ptolemaic system, the oscilla- 
tion of the plane of the orbit of a planet, which 
was supposed to account for certain inequalities 
in the latitude Conjugate deviation, in paihol., 
the forced and persistent turning of both eyes toward one 
side, without altering their relations to each other, seen 
in some cases of brain lesion. Deviation of a falling 
body, that deviation from the perpendicular line of de- 
scent which is caused by the rotation of the earth on its 
axis. Deviation of a projectile, its departure from a 
normal trajectory. Deviation of a ray of light, in 
opties, the change of direction a ray undergoes in pass- 
ing from one medium to another. (See refraction.) The 
minimum of deviation, or least change of direction, for 
a ray passing through a prism, takes place when the 
angles of incidence and emergence are equal. Devia- 
tion of the compass, the deviation of the north point 
of a ship's compass from the magnetic meridian, caused 
by the counter-attraction of the iron in the ship. For 
ships which are to remain in the same magnetic lati- 
tude, this error may be coirected or compensated by 
placing magnets near the affected compass. Compasses 
are frequently elevated above the deck on tripods or 
musts to obviate the effects of the ship's magnetism, the 
direction and amount of which depends to a certain ex- 
tent upon the position of the ship's head with reference 
to the points of the compass while building. In iron 
ships a careful determination of this error, with the 
ship's head on every point of the compass successively, 
is essential to safe navigation.- Primary deviation, in 
ophthal., the deviation of the weaker eye from that position 
which would make its visual line puss through the ol.jwt- 
point of the healthy eye.- Secondary deviation, in oph- 
thal., the deviation of the healthy eye from the posit i, m 
which would make its visual line puss through the ulijVft - 
point of the weaker eye. 
deviator (de'vi-a-tor), ii. [= F. deriateiir, adj., 
producing deviation; < LL. de-viator, one who 
deviates, < deviare, deviate: see deviate."] One 
who deviates. 
The greatest men of genius ... do not stand forth in 
their respective generations as dematorx from the Intel- 
