pendulum 
4372 
- 
the river. Pendulum governor, in meek., a governor 
the river. pendulum governor, in mecn., a govi 
consisting of two revolving pendulums, of equal length and penes n. Pll 
weight, attached to a spindle, the spindle and the pemlu- p e nestone 
Motley, 
Plural of penis 
ite = op. peiustrabiltaaa = Pg. penetrabtli- 
= It. penetrabilita, < L. as if *penctr<ibili- 
trolled. The angular velocity of revolution of the pen- 
dulums bears a constant ratio to the velocity of the prime 
mover. The pendulum-rods or -arms are thus made to 
take and hold a definite angle with the axis of their revolu- 
tion, so long as the speed of the prime mover remains con- 
stant. Increase of speed in the latter increases this angle, 
and decrease of speed diminishes it. The pendulum-arms 
are connected by links to a collar that slides on the spindle, 
and the motion of this collar is made to regulate a valve 
supplying steam or gas to an engine, a belt-shift that 
moves a belt on cone-pulleys, or mechanism controlling the 
partial opening or closing of a gate supplying water to a 
wheel, etc. The supply of power is thus varied according 
to requirements, and the variation in velocity is confined 
to narrow limits. See governor, 6. Pendulum press, 
a punchiug-press in which the punch is driven into the no-.*---!.!- fnmi'fi trn Ml n I" F nfuftnrtili- 
die by a swinging pendulous lever usually having a ball peneWaDie (pen e-tra-Di;, a. |= * . penciraote 
or weight at the lower end, and actuated by the foot of = Sp. penetrable = Pg. penetravel = It. penetra- 
trtlhililr 
dade 
ta(t-)s, < penetrabilis, penetrable: see penetra- 
ble.] Susceptibility of being penetrated; capa- 
bility of occupying a place occupied at the same 
time by something else. 
The immediate properties of a spirit or immaterial! sub- 
stance an penetrwOmf :md indiscerptibility. 
Dr. II. More, Immortal, of Soul, i. 2. 
All the facts which seem to prove penetrability only 
prove that the particles are mobile and separable, not that 
the particles themselves are penetrable. 
G. H. Lewes, Probs. of Life and Mind, II. iv. 4. 
the operator, while with his hands he holds the piece to 
be punched. Pendulum pump, (a) A direct-acting 
donkey-pump in which the fly-wheel oscillates in a verti- 
cal plane, (b) A pump in which the reciprocating mo- 
tion of the piston is controlled by a pendulum, (e) A 
pump the handle of which swings on either side of ite 
center of suspension. E. II. Kniijht. Simple pendu- 
lum, (a) See def. 2, above, (b) A pendulum consisting 
of a spherical bob suspended from a cord or wire. 
pendulum-hausse (pen'du-lum-hous), . See 
liausse, 1. 
pendulum-level (pen'du-lum-lev'el), n. Same 
as plumb-level. 
pendulum-spindle (pen'du-lum-spin"dl), n. 
The revolving shaft or spindle to which a re- 
volving pendulum is attached, and which im- 
parts motion to the pendulum. 
pendulum-wire (pen'du-lum-wlr), n. A kind 
of flat steel wire or ribbon used for the suspen- 
sion of clock-pendulums. penetrableness (pen'e-tra-bl-nes), n. The prop- 
pene 1 t, '* A Middle English form of pen 2 . erty of being penetrable; penetrability. 
pene 2 , n. and v. Seejwen. penetrably (pen'e-tra-bli), adv. So as to be 
Peneian (pe-ne'yan), a. [< L. Peneius, < Gr. penetrable. 
Utfvr/'iof, pertaining to the river Peueus,< Hr/vet^ penetrailt (pen'e-tral), n. [= Sp. Pg. penetral 
(> L. Peneus), a river of Thessaly, also the god = It. penetrate, <' L. penetralia, the inner or se- 
of that river; also, a river of Elis.] Of or per- cret part, the interior of anything: see pene- 
tralia.] The interior parts. See penetralia. 
bile,'< L. penetrabilis, that can be pierced, < 
penetrare, pierce, penetrate: see penetrate.] 1. 
Capable of beingpenetrated, entered, or pierced 
by another body. 
Let him try (for that 's allowed) thy dart. 
And pierce his only penetrable part. 
Dryden, tr. of Ovid's Metamorph., xii. 
2. Susceptible of moral or intellectual impres- 
sion. 
I am not made of stones, 
But penetrable to your kind entreats. 
Shale., Rich. III., iii. 7. 225. 
A spirit no longer penetrable to suffering. 
Noctes Ambrosianse, April, 1832. 
3f. Penetrating. [Bare.] 
His Graces sight was so quicke and penetrable that he 
saw him, yea, and saw through him, both within and 
without. Hall, Hen. VIII., an. 11. 
taining to the river Peneus, which runs through 
the Vale of Tempe in Thessaly, celebrated for 
its picturesque beauty. 
Illyrian woodlands, echoing falls 
Of water, sheets of summer glass, 
The long divine Peneian pass. 
Tennyson, To E. L., on his Travels in Greece. 
Penelope (pe-nel'o-pe), n. 
Penelopa, LL. 
also Penelopea, 
< Gr. 
Passing through the penetrailes of the stomach. 
Palmendos (1589). (Nares.) 
penetralia (pen-e-tra'li-a), n. pi. [< L. pene- 
tralia, pi. , the interior, an inner room, a sanc- 
tuary, etc., also rarely in sing, penetrale, pene- 
tral, neut. of penetralis, penetrating, internal: 
see penetrailt] 1. The interior parts of any- 
thing; specifically, the inner parts of a build- 
ing, as a temple or palace ; hence, a sanctuary, 
especially the sanctuary of the Penates. 2. 
Hidden things; secrets. 
The present work will be hailed as a welcome addition 
to our knowledge of these hitherto mysterious penetralia 
of Mohammedan superstition. 
B. Taylor, Pref. to Burton's El-Medinah. 
penetrance (pen'e-trans), n. [< penetran(t) + 
-ee.] Same as penetrancy. Dr. H. More, Psy- 
chozoia, ii. 12. 
penetrancy (pen'e-tran-si), n. [As penetrance 
(see -ey).] The property of being penetrant; 
the power of entering or piercing ; penetrating 
power; acuteness; sharpness. 
What sagacity of wit, what variety of learning, what 
penetrancy of judgment? 
Barrow, Pope's Supremacy, Supposition 6, 4. 
The subtilty, activity, and penetrancy of its effluvia no 
obstacle can stop or repel, but they will make their way 
through all bodies. Ray, Works of Creation. 
Penelope + -idx."] T" family of ^gallinaceous Penetrant (pen'e-trant), a. and n. [= F. pene- 
mous with Craeidx. C. L. Bona- tra nt=^. Pg. It. penetrante, < L. penetran(t-)s, 
[NL., < L. Penelope, 
woman's name, 
esp. the wife 
of Odysseus 
(Ulysses).] The 
typical genus 
of Penelopinx, 
founded by 
B. Merrem in 
1786, contain- 
ing a number 
of South and 
Central Ameri- 
can species of 
birds, such as 
P. marail, call- 
ed guans. Guan</v ' 
Penelopidfe (pen-e-lop'i-de), n. pi. [NL., < 
birds, synonymous 
parte, 1831. 
Penelopinse (pe-nel-o-pi'ne), n. pi. [NL., < 
Penelope + -inse.] A subfamily of Cracidse, 
founded by G. E. Gray in 1840, typified by the 
genus Penelope, and containing six other genera, 
Penelopina, Stegnolsema, Pipile, Aburria, Ciiamas- 
petes, and Ortalis (or Ortalida). The guans, as 
these birds are collectively called, number about 40 spe- 
cies, ranging from Texas through the greater part of South 
America. They are from 16 to 2fi inches long, of graceful 
form, with long tail and varied plumage ; they have bare 
skin on the head or throat, and in some cases a crest. 
They inhabit woodland, and are to some extent arboricole. 
See cuts under Aburria, gtian, Penelope, and Pipile. 
penelopine (pe-nel'o-pm), a. [< NL. Penelo- 
ppr. of penetrare, pierce, penetrate : see pene- 
trate."] I. a. Having the power to penetrate 
or pierce ; making way inward ; subtle ; pene- 
trating : literally or figuratively. 
The Food . . . mingled with some dissolvent Juices 
. . . [is] evacuated into the Intestines, where . . . it is fur- 
ther subtiliz d, and render'd so fluid and penetrant that 
the thinner and finer Part of it easily finds its Way in at 
the straight Orifices of the lacteons Veins. 
Bay, Works of Creation, p. 27. 
The lady, ever watchful, penetrant, 
Saw this with pain. Keats, Lamia, ii. 
II. . An acute and penetrating person. 
[Rare.] 
n , ;? 
Penelopized ppr -.. 
def) + -ize.] To act like Penelope, the wife 
pp. penc- 
penetratus, pp. 
. 
[< Penelope (see tmted, ppr. penetrating. . 
e -ize. o act like Penelope, the wife of penetrare (> It. penetrare = Pg. Sp. Pr. pee- 
of Ulysses, when she was pressed by the suit- trar = "F.penetrer),^*, set, or place within, en- 
penetration 
ter, pierce, penetrate, < penes, within, with (ef. 
penitus, within), + -trare (as in intrare, go in, 
enter, < intra, within), < / trn, cross over, pass, 
as in trans, across, etc. (see trans-), Skt. i/ tar, 
cross.] I. trans. 1. To pierce into or through ; 
enter and make way into the inner or interior 
parts of : as, the rays of lightpenetrated the thick 
darkness of the cave. 
Volumes of sound, from the Cathedral rolled, 
This long-roofed vista penetrate. 
Wordsworth, Desultory Stanzas. 
lie came near success, some of his troops penetrating the 
National lines at least once. 
U. S. Orant, Personal Memoirs, I. 417. 
2. To enter and affect deeply; influence; im- 
press ; hence, to enter and become part of; per- 
meate : as, to be penetrated with a sense of grat- 
itude. 
That little cloud, in ether spread 
And penetrated all with tender light. 
Wordsworth, Sonnets, ii. 20. 
The fair forms of Nature were never penetrated with so 
perfect a spirit of beauty. 
B. Taylor, Lands of the Saracen, p. 165. 
The schools of China have always been penetrated with 
the religion of China, such as it is. 
A. A. Hodge, New Princeton Rev., III. 33. 
3. To arrive at the inner contents or the mean- 
ing of ; see through; discern; discover: as, to 
penetrate a mystery; to penetrate a design. 
Nature hath her unities, which not every critic can pen- 
etrate. Lamb, My Relations. 
= Syn. 1. Penetrate, Pierce, Perforate, Bore through, Trans- 
Ax. Penetrate may mean no more than to make entrance 
into, and that slowly or with some difficulty, or it may have 
the meaning of pierce. Pierce means to penetrate deeply 
and quickly, and therefore presumably, although not ne- 
cessarily, with some sharp instrument. (See Heb. iv. 12.) 
Perforate and bore through mean to make a hole through, 
the former generally expressing the making of a smaller 
hole, the latter expressing sustained labor or slowness : as, 
the book- worm perforates leather binding ; the carpenter 
bores through a beam ; a bullet perforates or pierces the 
body. To transfix is to pierce through, the instrument re- 
maining in that which is transfixed : as, to transfix a bird 
with an arrow ; to transfix a butterfly with a pin. 
II, intrans. To enter by piercing; pass, as 
a piercing instrument ; enter and make way ; 
reach by piercing: literally or figuratively: 
usually followed by to or into. 
The contemplations of man do either penetrate unto 
God or are circumferred to nature. 
Bacon, Advancement of Learning, ii. 147. 
But soon the light . . . descends on the plain, and pen- 
etrates to the deepest valley. 
Macavlay, Sir James Mackintosh. 
penetrating (pen'e-tra-ting), p. a. [Ppr. of pen- 
etrate, v.] 1. Having the power of passing 
into or through (something); sharp; subtile: 
as, a penetrating odor. 2. Acute; discerning; 
quick to discover or recognize: as, a, penetrat- 
ing mind. 
Men of the largest sense, of the most penetrating insight. 
Craik, Hist Eng. Lit, I. 495. 
penetratingly (pen'e-tra-ting-li), adv. In a 
penetrating or piercing manner; with quick 
discernment; acutely. Wright. 
penetration (pen-e-tra'shon), n. [= F. pene- 
tration = Pr. penetratio = Sp. penetration = Pg. 
penetraqeCo = It. penetrazione, < LL. penctra- 
tio(n-), a penetrating or piercing, < L. yene- 
trare, penetrate, .pierce: see penetrate.] 1. The 
act of penetrating or piercing. 2. Power of 
penetrating; specifically, in gun., the depth a 
projectile will pass into any material against 
which it is fired. The penetration into earth or sand 
is generally expressed in feet ; into armor or metal plat- 
ing, in inches. The English "thick-plate formula," now 
much used by artillerists, is t = - . -i -- in which ( = 
U.OU _.0->:> 
the penetration in inches, and E = the energy in foot- tons 
per inch of circumference of shot 
3. Mental acuteness ; discernment; insight: as, 
a man of extraordinary penetration. 
To a profound philosopher like myself, who am apt to 
see clear through a subject, wherethepenra(i(mof ordi- 
nary people extends but half way, there is no fact more 
simple and manifest than that the death of a great man is 
a matter of very little importance. 
Irving, Knickerbocker, p. 266. 
4. In optics: (a) Of a microscope objective, its 
power of giving fairly distinct vision for points 
both inside and outside of its exact focus. (6) 
Of a telescope, its space-penetrating power, as 
Herschel called it i. e. the number of times 
by which the distance of an observed star 
might be increased while still appearing of the 
same brightness in the telescope as it does to 
the naked eye. It is proportional to the square root 
of the illuminating power, and for an achromatic tele- 
scope is approximately equal to four times its aperture 
in inches. Penetration-twin. See tmn. =Syn. 3. Dis- 
crimination, etc. (see discernment), sagaciousness, shrewd- 
ness, sharpness. 
