I fc> X. - 
04- 
optic 
it are'eallrd I" liiiinnn anatomy the mile* and 
< of (hi- brain. The optir nerves arise in pail tnim 
Ilir optic lot>. - 1 tn important loin's ileiTrasc ill lrl;i 
live Hi/i 1 ii" the >crtcbrate -rale ascends; linn, in some 
ti-lirs they art- quit*- an large as (in- ci-i dual licinisphere, 
and lif nncoMTetl upon the surface of the brain ; they an- 
quite larni' in reptiles mill liir.ln ; aniiill ill mammals (in 
man smallest in promotion )>otti to tlir o i.-iuuni and to 
III- . -.-i.'lirllnni), afi'i i-ntilrly cuvi-rrd in, so that they ilu 
IMI! ;i|i|> ;n upon (he surface of the hruiii. See ciltB under 
rfrr'irill. ami rurini* OptiC nerves (nervi optici). the 
nerves of sight ; tin- nerves of the special sense of vision, 
arising from tbe anterior c|mi<lrigcniinal and external 
i:cliiriilatr buili's :inil the pnlvinar, all'l t'Tliiinating in 
(he retina Them- m-rn > are purely sensory, and by 
means of 1 1 in ii tin retinal Hti mil hit ions atfect the brain a 
process by which vision is accompli shed. The optic nerves 
of opposite -iih- ilrrussate or form the optic chiasm, unit 
the phrase IB sometimes restricted to the part of these 
nrrv. MIS trunks beyond the chiasm, tin- rest, being called 
the t'l'ti'- tnti-l. SIT nil- inilri brain, rnrjurt. and '//<*'. 
Optic neuritis. s p r u>'uriti< ami euts under corpus and 
''.'/'''.' Optic pad, a pad like elevation at the end of the 
arms of a itarHsh on which an eye Is situated. Optic 
papilla. .Same us <tjttir <li*k. Optic peduncle, In crus- 
taceans, an eye-stalk or optlthalmito. OptlC Stalk, In 
mollusks, a soft process of the head upon which the eye 
is UppOfted, a> in various snails, etc.; an omniatuphiii . 
See Slj/JommatopAro. Optic thalamus, a large gan- 
glion of the thalainencephalon. situated upon the cms 
and separated from the lenticular nucleus by the Internal 
capsule. It gives origin to some of the libers of the optic 
nerve. Alno called thalamw. Sec cuts nndercrre/waJ and 
corpus. -Optic tract (tractua optici), the part of the 
whole course of the optic nerves which is between the 
i-liiasin and the respective origins of the uervea. In man 
the tracts are narrow Hat bands of white nerve-tissue 
crossing the crura, to which they are closely attached. - 
Optic tubercles, the corpora <|iiadrigcinina. See biyemi- 
num. Optic vesicles, in embn/ot. , a pair of vesicles de- 
veloped from the anterior cerebral vesicles of the embry- 
onic brain. = Syn. Optic, Optical. The former is chiefly snid 
of the anatomy of the eye and of the physiology of vision, 
the latter chiefly of the science of optics: as, ttptic nerve, 
tract, lobe ; optical angle, center, effect. 
II. n. 1. The eye. [Now chiefly collocj.] 
(Quickly cold Indiff'renco will ensue. 
When you Love s Joys thro' Honour's Optic view. 
Prior, Celia to Damon. 
She screwed her dim optics to their aeutest point, in the 
hope of making out with greater distinctness a certain 
window. Hawthorne, Seven Gables, xvi. 
2f. An eye-glass; a magnifying glass. 
I was as glad that you have lighted upon so excellent a 
Lady as if an Astronomer by his Optics had found out a 
new Star. llmrett. Letters, I. vi. SO. 
The sins we do people behold through optics 
Which shew them ten times more than common vices. 
Beau, and f'l., Thierry and Theodoret, I. 1. 
optical ( op'ti-kal), ii. [< optic + -al.~\ 1. Relat- 
ing to or connected with the science of optics; 
based on or constructed in accordance with the 
laws of optics: as, optical l&ws', optical instru- 
ments. 2. Pertaining to vision; optic. 3. 
Treating of or studying optics : as, optical writ- 
ers. Boyle, Works, I. 673. Optical anomaly, see 
anomaly. - Optical center, in a lens, a point so situated 
that the direction of every ray passing through that point 
remains unaffected by its transmission through the lens 
that Is, the incident and emergent parts of the ray are 
parallel. Geometrically it is dellned as the point In which 
the optical axis of the lens la cut by the line Joining the 
two points where any pair of parallel planes touch the 
opposite surfaces of the lens. In a double-convex or dou- 
ble-concave lens the optical center lies within the lens ; 
in a plano-convex or plano-concave lens it is the point 
where the curved surface of the lens is pierced by the 
axis ; in the meniscus and concavo-convex it lies outside 
of the lens, beyo id the surface which la moat strongly 
curved. If the thickness of the lens is small compared 
with its focal length, the dimensions of object and image 
will be very nearly proportional to their distances from 
the optical center. Combinations of several lenses do not 
possess an optical center. Optical circle, in physics, a 
graduated circle, fitted with the necessary appliances, used 
for illustrating the lawa of refraction aim reflection, or, 
when accurately constructed, for measuring Intel-facial 
angles, refractive indices, etc. Optical densimeter, 
equation, glass, meteorology, square, etc. See the 
nouns, syn. See optic. 
optically(op'ti-kal-i), iidr. As regards sight or 
tlir laws of sight; in accordance with or with 
reference to the science of optics or the use of 
optical instruments ; by optical means Opti- 
cally active substance. See active. 
optician (op-tish'an), it. [= F. opticien; as op- 
fir + -in H.'] I. A person skilled in the science 
of optics. 2. One who makes or sells optical 
glasses and instruments. 
opticist (op'ti-sist), n. [< optic + -ist.] A per- 
son skilled or engaged in the study of optics. 
The real cause of the luminosity of the eyes of animals 
in the dark Is now thoroughly understood by physiological 
nptinstt. Pop. Sci. Mo., XXIV. 814. 
Opticociliary (op"ti-k6-sU'i-a-ri), a. [< ML. </,- 
lii'ii.i. optic, + ciliaris, ciliary.] Pertaining to 
the optic and ciliary nerves Opticociliary neu 
rectomy, the exsection of portions of the optic and cil- 
iary nerves Opticociliary neurotomy, the division of 
the optic and ciliary nerves. 
optics (on'tiks), . [PI. of opt ic: see -i.] That 
branch of physical science which treats of the 
nature and properties of light, of the theory of 
260 
H33 
colors (chromatics), of the change which light 
suffers it her in it socialities or in its course when 
refracted nr Iriinsmitteil tliroiigh limlirs (diop- 
trh's), when reflected from their surfaces or 
when passing near them (catoptrics), of the 
structure of the eye and the laws of vision, ami 
of the construction of instruments of intro- 
spection, as telescopes, niirroscopi >. eto, -Qeo- 
metrical optics. >' < v" < '">. Physical optics, that 
branch of optics which includes the phenomena of diffrac- 
tion, interference, ilonbli refraction, and in general that 
division of tile subject wbieb is explained by reference to 
the undulating theory and the behavior of light-waves 
under various conditions. Physiological optics, that 
branch of physiology which treats of the eye and thesight- 
functlon. 
optigraph (op'ti-griif), H. [Irreg. < Or. !>- 
of seeing, + -//u'lifin-. write.] A form of tele- 
scope constructed for the purpose of copying 
landscapes, etc. It Is suspended vertically in gimbals 
by the object-end, beneath a fixed diagonal plane mirror, 
which reflects the rays from the objects to be drawn 
through the object-glass of the instrument toa speculum, 
and thencethrongh theeye-glasstotheeye. Between the 
eye and the speculum la a piece of parallel-faced glass with 
a small dot on Ha center, exactly in the focus of the eye- 
glass. Thin dot Is made to pass over (he outlines of an 
object, and a pencil fixed at the eye-end traces the deline- 
ation on paper. 
optimacy (op'ti-ma-si), . [< optima(te) + -n/.] 
1 . The body of optimates or aristocrats ; the 
nobility. Hammond. fBare.] 2. Government 
by the optimates ; aristocracy. 
Where the noble or the rich held all the power, they 
called their own government aristocracy, or government of 
the better sort, or optimacy, government of the best sort, 
J. Adams, Works, IV. 478. 
optimate (op'ti-mat), n. and n. [< L. optima ti.*. 
pi.: see optimates.] I. a. Of or belonging to 
the optimates or nobility; noble. Eclectic Ber. 
[Bare.] 
n.t '< One of the optimates. 
In any flourishing state, 
Whether by King swald, or by optimate. 
Heywood, Works (ed. Pearson, 1874), VI. JCttS. 
optimates (op-ti-ma'tez), n. pi. [L., < optima.*. 
the best: see optimum.'] The Roman aristoc- 
racy, including the nobilitas, a large part of the 
equites, and their supporters; hence, an aristoc- 
racy or nobility in general. 
As to the modeof electing the senate, . . . or optimates 
before mentioned, . . . disposition was made by this new 
law for the reformation of the government. 
J. Adams, Works, V. 125. 
After the 7th century the optimates at the head of the 
army were also at the head of the citizens. 
Km- HI: Brit., XX. 785. 
optime (op'ti-me), n. [< L. optime, very well (as 
uptime meren(t-)s, very well deserving), < opli- 
mug, very good, best: see optimum.] In the 
University of Cambridge, England, one of those 
in the second or third grade of honors in math- 
ematics, the wranglers constituting the first 
rank, and the senior and junior optimes the sec- 
ond and third respectively. 
All candidates for Classical Honors are nrst obliged to 
obtain a place among the Junior Optimes I if not higherl 
that is to say, in the third class of the three Into which 
the Mathematical Tripos is divided. 
C. A. Bristed, English University, p. 85. 
optimeter (op-tim'e-ter), n. Same as optome- 
ter. 
optimise, v. i. See optimize. 
optimism (op'ti-mizm), . [< P. optimisme = 
Sp. Pg. optimismo = It. ottimismn = G. optimis- 
mus, < NL. optimismus, < L. optimns, optumn.*, 
very good, best: see optimum.] 1. In mctaph.: 
(a) Properly, the metaphysical doctrine of 
Leibnitz that the existing universe is the best 
of all possible universes. The most characteristic 
moments of the doctrine are two : first, that the Creator 
selected this universe from a number of others which he 
might have created ; and, second that all of these present- 
ed certain imperfections or disadvantages which omnipo- 
tence could not avoid. (6) The doctrine that the 
universe advances on the whole, so as to be 
tending toward a state in the indefinite future 
different in its general character from that in 
the indefinite past. This is better called eeoluNnnimi. 
It is opposed to pessimism, which holds that the universe 
is tending to the nothingness from which It sprang, and 
to Epicureanism, which holds that the universe is not tend- 
ing from any general state to any other general state. 
2. The belief, or disposition to believe, that 
whatever exists is right and good, in some in- 
scrutable way, in spite of all observations to 
the contrary. 
The Christian optimism ia the recognition that in a spir- 
itual world a spiritual being, as such, cannot find an abso- 
lute limit or foreign necessity, against which his life must 
be broken in pieces; but that, on the contrary, all appa- 
rent outward limits, and even death itself, are for it but 
the means to a higher freedom and realisation of self. 
E. Caird, Hegel, p. 217. 
option 
It seemed to chill the flow of the good fellow's optimism, 
ao that he assented with but lukewarm Katlsfaclion. 
ll'niflls. Modern Instance, Ix. 
Optimist (op'ti-mist). a. and n. [= F. opti- 
inixti- = Sp. I'g. 'i/ilin/intd = It. iilliniistii = G. 
nptiiitixt ; as ii/iliiii-ixiii + -i.it.] I. 11. 1. ' >ne 
who believes in tin- metaphysical doctrine of 
optimiMn. 
The optimists of our century have followed In the wake 
of Spin../:, .ir Leibnitz. .V. A. Her., CXXV1I. 404. 
2. One who believes in tlie present or iillimnie 
supremacy of good over evil ; one who always 
hopes for and expects the best; a person of 
hope. t'nl disposition. 
One such I knew long since, a whIU-huired man, . . . 
\ :,!, ui ,.'.,,.,-' Bryant, Old Mail's Counsel. 
II. . Of or pertaining to optimism ; optimis- 
tic: as, the niiliiiiixt view. 
optimistic (op-ti-mis'tik), a. [< optintixt + -ic.] 
of, pertaining to, or characterized by opti- 
mism; disposed to take the most hopeful view 
of a matter; hopeful; sanguine. 
If we confine ourselves to the health of women, we 
shall find that the figures hardly justify ua In awnming a 
purely optimistic attitude. Pop. Sci. Mo., XXVIII. inn. 
optimistically (op-ti-mis'ti-kal-i), adv. In ac- 
cordance with optimism, or the view that every- 
thing is ordered for the best ; in a hopeful or 
sanguine manner ; hopefully. 
optimityt(op-tim'i-ti), . [< LL. <iptimita(t-)g, 
excellence, < L. 6'ptimus, best, very good: see 
til'timnm.] The state of being best. Bailey, 
1731. 
optimize (op'ti-iniz), v. i. ; pret. and pp. opti- 
mized, ppr. uptimising. [< optim-ism 4- -ize.] 
1. To hold or express the doctrines or belief of 
an optimist. Saturday Rev. 2. To take the 
most hopeful view of a matter ; hold or main- 
tain hopeful views habitually. 
It la pleasant to argue, as I have thus far argued, the 
optimizing side of the question fof auffrage]. 
(Jladstone, Gleanings of Paat Years, I. 160. 
Also spelled optimise. 
optimum (op'ti-mum), n. [NL., neut. of L. 
ojitimus, optitmus, best, very good, superl. (as- 
sociated with bonus, good), < / op in optare, 
choose: see optate.] In hot., one of the three 
cardinal points of temperature namely that 
point at which the metabolic processes are car- 
ried on with the greatest activity. "Theminimum 
or zero point is the point at which the performance la 
just possible; the optimum point, at which It is carried 
on with the greatest activity ; and the maximum point, at 
which it is arrested." (Vines.) 
Every vegetative (and fructiflcatlve) process haa certain 
If mita of temperature, and a fixed optimum In each speciea. 
II: Bary, r uugi (trans.), p. 353. 
option (op'shon), n. [< F. option = Sp. opcion 
= Pg. ongSo, { L. optio(n-), choice, free choice, 
optionX optare, choose : see opiate.] 1. Choice ; 
wish; preference; election. 
Transplantation must proceed from the option of the 
people, else it sounds like an exile. Bacon. 
2. The power or liberty of choosing; the right 
or power of choice ; the opportunity of electing 
or selecting an alternative or one of several 
lines of conduct ; the power of deciding on a 
course of action: as, that is not left in my op- 
tion; it is at your option to take it or leave it. 
In the European nations a constantly Increasing niim- 
ber of persons find themaelve* In circumstances In which 
a large option is allowed them as to the plan on which 
they will conduct their lives. 
T. H. Green, Prolegomena to Ethics, } 8S5. 
3. In Eng. canon law, the right, now obsolete, 
which an archbishop formerly had, on conse- 
crating a bishop, of selecting a benefice in the 
i.i-hop's diocese for one of his own chaplains. 
4. On stock and other exchanges, a privilege, 
secured by the payment of a certain premium or 
consideration, either ( 1 ) of calling for the deliv- 
ery, or (2) of making delivery, of a certain spe- 
cified amount of some particular stock or kind 
of produce, at a specified price, and within spe- 
cified limits of time. The first kind of option is usually 
designated a call, and the second a put ; but both are some- 
times called futures. 
5t. A wishing; a wish. 
I shall conclude this epistle with a pathetlck option : 
O that men were wise ! 
Layman's Dtf. of Christ (1730), p. 23. 
Buyer's option. See buyer. Local option. See local. 
Seller's option. See seller. =Syn. i Option, Choice, 
Preference, Election. Option ia the right of choice, the 
freedom to choose between two or more : as, "there ia no 
option," Shedd, Homlletlcs, p. 30. Choice is primarily the 
act of choosing, but, by extension, may be the same as 
option : as, he gave him the choice. Preference Is prima- 
rily the state of mind determining the choice, and sec- 
