parallel 
brake-hanger. See bari, etc. Parallel circles on a 
sphere, circles whose planes are parallel. Parallel cir- 
cuit, an electrical conductor joining two points which are 
also connected by another conductor, to which the first is 
then said to be parallel. Parallel coping, in building. 
coping of equal thickness throughout : used to cope inclined 
surfaces, such as gables, etc. Parallel curves and sur- 
faces, those curves and surfaces which have the same nor- 
mals, and are therefore everywhere equidistant, Parallel 
extinction. See extinction.,*. Parallel file. See/iei. 
Parallel fissure or sulcus, the superior temporal Hssure, 
parallel to the fissure of Sylvius. See Assure. Parallel 
forces forces which act in directions parallel to each 
other. Parallel hemihedrism. See hemihedrism. 
Parallel intervals. Same as eonseealice intervals (which 
see,w\Acr consecutive). Parallel key, knife, lathe. See 
the nouns. Parallel lines, (a) Defined by Euclid as 
"straight lines which are in the same plane and, being 
produced ever so far both ways, do not meet." (6) Milit., 
sameasparaHcfe. See II., 5. Parallel motion, (a) A 
contrivance for converting reciprocating circular motion 
into rectilinear reciprocating motion by the use of link- 
work. The ordinary parallel motion, that of Watt, fulfils 
its function to a close degree of approximation, but not 
exactly. It is designed to cause the piston-rod in impart- 
ing motion to, and the pump-rod in taking motion from, 
the oscillating beam of a steam-engineTto move respective- 
ly in very nearly right lines, and is sufficiently perfect for 
all practical purposes. It depends upon the principle that 
when the ends of two levers connected by a link oscillate 
on different centers in the same vertical plane, describing 
arcs convex toward each other, there is some point in the 
connecting-link that must move in nearly a right line. 
The position of this point depends upon the lengths of the 
levers and the relative positions of their f ulcrums. A meth- 
od for mathe- 
matically loca- 
ting this point 
has been given 
byRankine. In 
the diagram 
the ends of the 
equal levers g h 
and ij describe 
arcs convex to- 
ward each oth- 
er ; a is the con- 
necting-link ; g 
and j are the 
fulcrums. The 
piston-rod is 
connected at b 
to the link c; 
and when the 
ILL 
Part of Beam of Condensing-engine. 
Parallel Rulers. 
rt<?', rulers ; b b' , bars pivot- 
ed to the rulers. The centers 
of the pivots being equidistant 
in * and A'. the rulers will there- 
fore be parallel to each other 
in any position of the bars. 
levers are caused to oscillate, one end of the link a is drawn 
to the right, while the other is moved to the left, causing 
the point of connection, and also the pump-rod / and pis- 
ton-rod e, to move in nearly right lines. The first exact 
parallel motion discovered, after immense labor by many 
mathematicians, was Peaucellier's cell. (See cell.) The 
simplest is the Kempe-Sy'vester parallel motion. (6) In 
music. See motion. Parallel perspective, rod, etc. See 
the nouns.- Parallel roads, benches or terraces on 
hill-slopes, indicating former levels at which the water 
stood in the valley beneath at a time when this was occu- 
pied by a lake, or a lake-like 
expansion of a river. The 
phrase parallel roads is chiefly 
used with reference to the so- 
called Parallel Roads of Glen- 
roy in Scotland, in regard to 
which there has been much 
discussion among geologists. 
See terrace. Parallel rulers, 
an instrument for plotting 
courses on a chart, or for draw- 
ing parallel lines for other 
purposes. It consists of two 
rulers connected by cross-bars 
of equal length, movable about 
joints, so that while the distance between the two rulers 
may be increased or diminished, their edges always remain 
parallel. Parallel sailing, sphere, etc. See the nouns. 
Parallel sulcus. See parallel fissure. 
II. n. 1. A line parallel to another line. 
That 's done, as near as the extremest ends 
Of parallels, as like as Vulcan and his wife. 
Shak.,T. andC., i. 3. 168. 
Lines that from their parallel decline, 
More they proceed, the more they still disjoin. 
Garth, Dispensary, iv. 186. 
"Who made the spider parallels design, 
Sure as De Moivre, without rule or line ! 
Pope, Essay on Man, iii. 103. 
2. The intersection of a sphere by a plane per- 
pendicular to its axis : such intersections of the 
terrestrial sphere are parallels of latitude, and 
are commonly represented on maps by lines 
drawn to every five or ten degrees (or less dis- 
tances) between the equator and the poles. 
See latitude, 4. 3. Comparison made by pla- 
cing things side by side: as, to draw a, parallel 
between two characters. 
No high-strain'd Parallel was made but thus, 
As good, or brave, as Aphrodisius. 
J. Beaumont, Psyche, ii. 56. 
'Twixt earthly females and the moon 
All parallels exactly run. Swift. 
He runs a laboured parallel between Schiller, Goethe, 
and Kotzebue ; one is more this, the other more that. 
Carlyle, Taylor's Survey of German Poetry (Essays, 
[III. 316). 
4. A thing equal to or resembling another in 
all essential particulars ; a counterpart. 
She is the abstract of all excellence, 
And scorns a parallel. 
Fletcher (and Massinger T), Lovers' Progress, iii. 3. 
4278 
In Britain where was he 
That could stand up his parallel' 
Shak., Cymbeline, v. 4. 54. 
The nearest parallels [to the conquest of Britain] that I 
can find are the Hebrew conquest of Canaan and the Sara- 
cen conquest of Africa. 
E. A. Freeman, Amer. Lects., p. 127. 
5. Milit., a trench cut in the ground before a 
fortress, parallel to its defenses, for the purpose 
of covering the besiegers from the guns of the 
place. 6. In printing, a mark of reference in a 
printed text, thus ||, used to direct attention to a 
marginal note or a foot-note. 7. In music. See 
I. ,4 In parallel,amethod of connecting electric batter- 
ies ordynamos in which all of thepositivepoles are joined to 
one extremity of the circuit-wire, and all of the negative to 
theother. (Seebattery.) Theconnectionissaidtobeinsmes 
when tlie positive pole of one cell or machine is joined to 
the negative of the next. Mundane parallel, in astral., 
situation at equal distances from the meridian. Parallels 
of altitude, in astron., small circles of the sphere parallel 
to the horizon. Also called almucaiitars. Parallels of 
declination, small circles of the celestial sphere parallel 
to the equator. Theory of parallels, the geometrical 
discussion of the number of lines which can be drawn 
through a given point parallel to a given line, with other 
kindred matters. The fifth postulate (in some modern 
editions the eleventh axiom) of Euclid reads, "And if 
a right line incident upon two right lines make the two in- 
terior angles on the same side less in sum than two right 
angles, then those two right lines will meet on the side 
on which the angles are less than two right angles if pro- 
duced to infinity. " This proposition being much more com- 
plicated than any other assumed by Euclid without proof, 
a great number of attempts were made by mathematicians 
to demonstrate it. Finally, it was conclusively shown, as 
Gauss expressed it, that we have no reason to believe that 
the celebrated postulate is more than approximately true. 
There are thus three possible systems of geometry, the Eu- 
clidean and two non-Euclidean systems, according as it is 
assumed that there can be drawn through any given point, 
parallel to any given line, only one line, two real lines, 
or two imaginary lines. Zodiacal parallel, in astral., 
the situation of two planets at the same distance from the 
equator. 
parallel (par'a-lel), v. ; pret. and pp. paralleled 
or parallelled, ppr. paralleling or parallelling. 
[<. parallel, a.] I. trans. 1. To place in a po- 
sition parallel to something else ; make parallel. 
The needle . . . doth parallel and place itself upon the 
true meridian. Sir T. Browne, Vulg. Err., ii. 2. 
2. To make conformable to something else; 
make the same or closely similar in many or all 
essential particulars. 
His life is paralleled 
Even with the stroke and line of his great justice. 
Shak., M. for M., iv. 2. 82. 
3. To match; equal; rival. 
For rapes and ravishments he parallels Nessus. 
Shak., All's Well, iv. 3. 281. 
He parallels 
Strong sinnewed Sampson, or, indeed, excels. 
Times' Whistle (E. E. T. S.), p. 25. 
Those distinct feelings which can be remembered and 
examined by reflection are paralleled by changes in a por- 
tion of the brain only. W. K. Clifford., Lectures, II. 82. 
4. To show or furnish an equal to, or an equiv- 
alent for. 
Well may we fight for her whom, we know well, 
The world's large spaces cannot parallel. 
Shak., T. and C., ii. 2. 162. 
5. To compare. 
I thought once . . . 
To have paralleled him with great Alexander. 
B. Jonson, Sejanus, i. 1. 
I paralleled more than once our idea of substance with 
the Indian philosopher's he-knew-not-what which sup- 
ported the tortoise. Locke. 
6. To take a course parallel with. [Recent.] 
Another railroad has paralleled the Nickel Plate, which 
has paralleled the Lake Shore. 
New York Tribune, March 23, 1884. 
II. intrans. To be like or equal ; agree. 
Sound paralleleth in many other things with the sight. 
Bacon, Nat. Hist., 125. 
parallelable (par'a-lel-a-bl), a. [< parallel + 
-able.'] Capable of being paralleled. [Rare.] 
Our duty is seconded with such an advantage as is not 
parallelable in all the world beside. 
ftp. Hall, Remains, p. 277. (Latham.) 
parallelepiped (par-a-lel-e-pip'ed or -pi'ped), 
. [Commonly, but erroneously, parallelopi- 
ped; = F.paralletepipedc = Sp. paralelepipedo, 
, < -apaM.ri'Aof, parallel (see parallel), + 
eiriirsSov, a plane surface, neut. of tTrwrcdof, on 
the ground, < siri, on, + ne aov, ground.] A prism 
whose bases are parallelograms. 
parallelepipedal (par-a-lel-e-pip'e-dal or -pi'- 
pe-dal), a. [Also, erroneously, parallelopipe- 
dal; < parallelepiped + -al.] Having the form 
of a parallelepiped. 
parallelepipedon (par-a-lel-e-pip'e-don or -pi'- 
pe-don), n. Same as parallelepiped. 
parallelogrammic 
parallelepipedonal (par-a-lel-e-pip'e-don-al or 
-pi'pe-don-al), a. [< parallelepipedon + -al.] 
Same as parallelepipedal. 
parallelinerved (par'a-lel-i-nervd), a. [< L. 
parallcltts, parallel, + nervus, nerve: see 
nerve.'] Same as parallel-nerved. 
parallelism (par'a-lel-izm), n. [= F. paralle- 
lisms = Sp. paralelismo = Pg. It. parallelismo, 
< MGr. TmpaAAr/Aia/ji6<;, a comparing of parallels, 
< irapa%A7/At(eiv, place side by side : see parallel- 
ize.] 1. A parallel position, in any sense of the 
word parallel. 
The fissures . . . were produced with such irresistible 
force as to preserve their linear character and parallelism 
through rocks of the most diverse nature. 
&'$(, Geol. Sketches, ii. 24. 
2. The retention by a moving line of positions 
parallel to one another. 3. Analogy. 
Now science and philosophy recognize the parallelism, 
the approximation, the unity of the two [Spirit and Mat- 
ter). Emerson, in N. A. Rev., t'XXVI. 419. 
Fortunately, literary parallelism is not synonymous with 
literary plagiarism. N. and Q., 7th ser., IX. 66. 
Specifically 4. The correspondence resulting 
from the repetition of the same sentiment or 
imagery, sense, or grammatical construction : a 
marked feature of Hebrew poetry. 
Parallelisms in sentences, in words, and in the order of 
words have been traced out between the gospel of Mat- 
thew and that of Luke. 
Paley, Evidences of Christianity, i. 8. 
5. A parallel or comparison. 
To draw a parallelism between that ancient and this 
more modern nothing. 
Glanrille, Vanity of Dogmatizing, xv. 
parallelistic (par"a-le-lis'tik), a. [< parallel 
+ -istic.] Of the nature of or involving paral- 
lelism; like, but not plagiaristie. 
parallelivenose (par-a-lel-i-ve'nos), a. [< L. 
parallelus, parallel, + "vena, vein: see venose.] 
In entmn., same as parallel-veined. 
parallelize (par'a-lel-Iz), v. t. ; pret. and pp. 
parallelized, ppr. parallelizing. [= Sp. para- 
lelizar,<. MGr. irapaUr/Mfciv, place side by side,< 
Gr. impaM.ri'Aoc,, parallel : see parallel.] To ren- 
der parallel ; place side by side for comparison ; 
arrange in parallel columns or positions. 
Of lesser grades, the series among Lacertilia of Aero- 
donta and Iguania, parallelized by Dum^ril and Bibron, 
and of Teidaj and Lacertidse, compared by Wiegmann. 
E. D. Cope, Origin of the Fittest, p. 95. 
parallellesst (par'a-lel-les), a. [< parallel + 
-lens.] Without a parallel ; peerless. [Rare.] 
Is she not parattettess? is not her breath 
Sweet as Arabian winds when fruits are ripe ? 
Beau, and Fl., Philaster, iii. 1. 
parallelly (par'a-lel -Ii), adv. In a parallel 
manner ; as a parallel or as parallels ; in a cor- 
responding manner; concordantly. 
parallel-nerved (par'a-lel-nervd), a. In l>ot., 
having the nerves parallel, as many leaves. 
Also parallel-veined. 
parallelodrome (par-a-lel'o-drom), n. [< Gr. 
irapaXkril.of, parallel, -F -6po/u>f, < dpa/tflv, run.] 
See nervation. 
parallelogram (par-a-lel'o-gram), n. [< OF. 
parallelogramme, F. parallelogramme = Sp. 
paralelogramo = Pg. parallelogrammo, para- 
lellogrammo, paralelogrammo = It. paralello- 
grammo, paralelogram- 
mo, < L. parallelogram- / ~~7 
mum, < Gr. wapaMqM- / / 
ypaft/tov, a parallelo- /_ / 
gram, neut. Of JrapoA- Parallelogram. 
AT/Aoypaftfiof, bounded by 
parallel lines, < napaM,jj^of, parallel, + ypafi- 
ja, line: see parallel and gram 2 .] 1. In geom., 
a quadrilateral whose opposite sides are par- 
allel. 2f. A pantograph. 
I had most infinite pleasure . . . with his shewing me 
the use of the Parallelogram, by which he drew in a quar- 
ter of an hour before me, in little, from a great, a most 
neat map of England. Pepys, Diary, IV. 65. 
Complement of a parallelogram. See complement. 
Parallelogram of forces. See/orcei. 
parallelogrammatic (par-a-lel"o-gra-mat'ik), 
a. [= F.parallelor/rammatique = Pg. parallelo- 
grammatieo; &s parallelogram + -ad'c 2 .] 1. Of 
or relating to a parallelogram. 2. Having the 
shape of a parallelogram: as, a, parallelogram- 
motif mark. 
parallelogranunatical (par-a-leFo-gra-mat'i- 
kal),. [< parallelogrammatic + -al.] Same as 
parallelogrammatic. 
parallelogrammic (par-a-lel-o-gram'ik), .. [< 
parallelogram + -ic.] Having the form of a 
parallelogram. 
