graving-piece 
graving-piece (gra'ving-pes), . 
hii/, a piece of wood inserted to supply the 
defects of another piece. Also called graven- 
pieoe, 
gravitate (grav'i-tat), . i. ; pret. and pp. ijrnri- 
tulfil, ppr. </rtiritatiny. [< NL. *ijr<irit<itus, pp. 
of "gravitare (> It. gravitare = Sp. Pg. gracitar 
= F. graviter, gravitate), < L. gravita(t-)s, hea- 
viness, gravity : see gravity.] 1. To be affect- 
ed by gravitation ; yield to the force of grav- 
ity; tend toward the lowest level attainable, as 
a rock loosened from a mountain. 
It is still extremely doubtful whether the medium of 
light and electricity is A gravitating substance, though it 
IB certainly material and has mass. 
Clerk Maxwell, Matter and Motion, cxlv. 
Hence 2. To be strongly attracted; have a 
natural tendency toward a certain point or 
object. 
The goods which belong to you gravitate to you, and 
need not be pursued with pains and coat. 
Emerson, Essays, 1st ser., p. 285. 
The colossal weight of national selfishness gravitates 
naturally to Toryism. Leeky, Eng. in 18th Cent., iii. 
gravitation (grav-i-ta'shon), . [= D. gravi- 
tatie = G. Dan. Sw. gravitation = F. gravita- 
tion = Sp. grar'itnrion = Pg. gravitaySo = It. 
gravitasione, < NL. *gravitatio(n-), < 'gravitare, 
gravitate: see gravitate.] 1 . The act of gravi- 
tating or tending toward a center of attrac- 
tion. 2. That attraction between bodies, or 
that acceleration of one toward another, of 
which the fall of heavy bodies to the earth is 
an instance. See gravity, 1. Gravitation can be 
neither produced nor destroyed ; it acts equally between 
all pairs of bodies, the acceleration of each body being 
proportional to the mass of the other; it is neither hin- 
dered nor strengthened by any intervening medium ; it 
occupies no time in its transmission ; its force is inverse- 
ly as the square of the distance ; and the amount of it is 
such that a particle distant one centimeter from an at- 
tracting gram of matter would by the action of gravitation 
alone, were no other force present fall into the center of 
attraction in 40 minutes and 20 seconds. Inasmuch as 
the masses of bodies can be measured otherwise than by 
their weights, namely, by their relative momentums un- 
der a given velocity, it follows that the modulus of gravi- 
tation, or the amount by which the unit mass attracts a 
particle at the unit distance, which is invariable, best dis- 
tinguishes gravitation from every other force. The laws 
of the attraction of gravitation were demonstrated by Sir 
Isaac Newton in 1687. 
The most considerable pheenomenon belonging to ter- 
restrial bodies is the general action of gravitation, where- 
by all known bodies in the vicinity of the Earth do tend 
and press towards its centre. Bentley, Sermons, vii. 
It is by virtue of gravitation that matter possesses 
weight ; for the weight of any thing is the expression of 
the force with which it tends towards the earth. 
W. L. Carpenter, Energy in Nature, p. 22. 
3. In philol., the tendency of sounds and syl- 
lables having little or no stress to become 
merged in the accented syllable, or to fall 
away entirely; the absorption of weaker ele- 
ments. [Rare.] 4. Figuratively, a prevail- 
ing tendency of mental or social forces or ac- 
tivities toward some particular point or result. 
Attraction of gravitation. Same as gravitation, 2. 
Gravitation constant. See constant, n. Gravitation 
measure of force. See the extract. 
It is sometimes convenient to compare forces with the 
weight of a body, and to speak of a force of so many pounds 
weight or grammes weight. This is called gravitation 
measure. Clerk Maxwell, Matter and Motion, xlvii. 
Modulus of gravitation. See def. 2. Terrestrial 
gravitation, gravitation toward the earth. Universal 
gravitation, the gravitation of all bodies in the universe 
toward one another. 
gravitational (grav-i-ta'shon-al), a. [< gravi- 
tation + -al.] Of, pertaining to, or caused by 
gravitation. 
Either the lunar theory is in some degree mathemati- 
cally incomplete, and fails to represent accurately the 
gravitational action of the earth and sun, and other known 
heavenly bodies, upon her movements ; or some unknown 
force other than the gravitational attractions of these 
bodies is operating in the case. Science, IV. 194. 
gravitationally (grav-i-ta'shon-al-i), adv. By 
gravitation, or in the manner of gravitation. 
The sun's initial heat was generated by the collision of 
pieces of matter gravitationally attracted together from 
distant space. Sir W. Thomson, Pop. Sci. Mo., XXXI. 20. 
gravitative (grav'i-ta-tiv), a. [< gravitate + 
-ice.] Of, pertaining to, or caused by gravita- 
tion ; gravitating or tending to gravitate. 
gravity (grav'i-ti), . ; pi. gravities (-tiz). [= 
G. gravitat = Dan. Sw. gravitet, < F. grarite = 
Sp. gravidad, gravedad = Pg. gravidade = It. 
gravitA, < L. gravita(t-)s, weight, heaviness, 
pressure, < graris, heavy: see grave 3 .] 1. 
Weight, as contradistinguished from mass; 
precisely, the downward acceleration of terres- 
trial bodies, due to the gravitation of the earth 
modified by the centrifugal force due to its ro- 
tation on its axis. The amount of this acceleration is 
2609 
about 385.1 inches (978 centimeters) per second at the sea- 
level and the equator, while at the poles it is 387.1 inches. 
(Jravity is a little less on mountains than at the sea-level, 
in the proportion of a diminution of one thousandth part 
at every two miles of elevation. There are also other 
slight variations of gravity, from which the figure of the 
geoid (which see) can be calculated. Generally speaking, 
gravity is in excess where the radius vector of the geoid 
is in excess of that of the mean spheroid. [The words 
gravity and gravitation have been more or less confound- 
ed ; but the most careful writers use gravitation for the 
attracting force, and gravity for the terrestrial phenome- 
non of weight or downward acceleration which has for its 
two components the gravitation and the centrifugal force. 
The centrifugal force at the equator is wo'iri of gravity. 
It is everywhere exerted in the plane of the meridian at 
right angles to the direction of the celestial pole. The 
direction of gravitation in middle latitudes is inclined 
about ll'.S to the radius of the earth. 
None need a guide, by sure attraction led, 
And strong impulsive gravity of head. 
Pope, Dunciad, iv. 76. ] 
2. Solemnity of deportment or character ; se- 
dateuess of demeanor; seriousness. 
Great Cato there, for gravity renowned. Dryden. 
When the French stage came to be reformed by Cardi- 
nal Richelieu, those long harangues were introduced to 
comply with the gravity of a churchman. 
Dryden, Essay on Dram. Poesy. 
His witticisms, and his tables of figures, constitute the 
only parts of his work which can be perused with perfect 
gravity. Macaulay, Sadler's Ref. Eefuted. 
We listen in public with the gravity of augurs to what 
we smile at when we meet a brother adept. 
Lowell, Among my Books, 1st ser., p. 379. 
3. Importance; significance; dignity. 
Length therefore is a thing which the grauilie and 
weight of such actions [prayer] doth require. 
Hooker, Eccles. Polity, v. 
They derive an importance from . . . the gravity ot the 
place where they were uttered. Burke. 
4. In acoustics, the state of being low in pitch : 
opposed to aeuteness Acceleration of gravity. 
See acceleration (6). Center of gravity. See center!. 
af gravity of a body 
gravity tends to move it ; the line along which the cen- 
ter of gravity would begin to fall if the body were free. 
Specific gravity, the ratio of the weight of a given 
bulk of any substance to that of a standard substance. 
The substance taken as the standard is water for solids 
and liquids, air or hydrogen for gases. The weights of 
bodies being proportional to their masses, it follows that 
the specific gravity of a body is equivalent to its relative 
density, and the term density has nearly displaced specific 
gravity in scientific works. As long as the term specific 
gravity was in use, water at 62 F. was taken as the stan- 
dard in England ; when the term density is used, water 
at its maximum density (4 C. or 39.2 F.) is the standard. 
If great accuracy is required, corrections must be made 
for temperature and for the buoyancy of the air. Thus, if 
we take equal bulks of water, silver, and platinum, and 
weigh them, the silver will be found to be 10.5 times and 
the platinum 21.4 times heavier than the water ; and reck- 
oning the specific gravity of water as unity, the specific 
gravity of silver is said to be 10.5, and that of platinum 
21.4. A common method of obtaining the specific gravity 
of solids is to weigh the body in air, then in pure distilled 
water, and divide the weight in air by the loss of weight 
in water, the result being the specific gravity of the body. 
There are, however, numerous other ways of obtaining this 
relation, as by the use of the pycnometer, the hydrometer 
(which seeX etc. See gravity-solution. 
The specific gravity of a body is the ratio of its density 
to that of some standard substance, generally water. 
Clerk Maxwell, Heat, p. 82. 
Specific-gravity beads or bulbs, small hollow spheres, 
usually of glass, used in determining the specific gravity 
of a liquid. If a number of them, each having its specific 
gravity marked on it, be thrown into the liquid, that one 
which just floats gives the required specific gravity, the 
others either sinking or floating. Specific-gravity bot- 
tle or flask, a pycnometer. 
gravity-railroad (grav'i-ti-ral"rod), n. A rail- 
road in which the cars move down an inclined 
plane, or a series of inclined planes, under the 
action of gravity alone. Such roads are often ar- 
ranged so that the loaded cars in descending pull a train 
of empty cars up to the summit ; or the empty cars may 
be hauled up by steam-power. 
gravity-solution (grav'j-ti-so-lu"shon), n. A 
solution used by lithologists for separating 
from one another the different minerals of 
which rocks are composed, by taking advantage 
of their difference* of specific gravity. The 
method is analogous to the process of ore-dressing, which 
is a separation of minerals differing in specific gravity in 
the large way, the fluid used being water. The essential 
difference, however, is that the fluid used by the litholo- 
gist is varied In specific gravity, by dilution, to just the 
desired conditions, while the water, of course, remains al- 
ways the same when used by the ore-dresser. The idea 
of using a gravity-solution in lithological research origi- 
nated with Thoulet in 1879. The fluid which he used was 
a solution of the iodide of mercury in iodide of potassium, 
having a density of 2.77 at 57 F. Several other solutions 
having a higher specific gravity have since that time been 
used. See specific gravity, under gravity. 
gravOUSt, a. [= Sp. Pg. It. yravoso, < ML. i/ru- 
I'OSHU, equiv. to L. graris, heavy, weighty, 
grave: see grave 9 , and cf. grievous.] Weighty; 
important. 
gray 
And farther the forsayd Lyon desired an abstinence of 
warre to be taken, tyll the two dukes might haue com- 
mnuication of yrauttus matters concernyng the welths of 
liothc these realmes. Hall, Edw. IV., an. fl. 
Prudent yrauoug persons. Hall, Hen. VII., an. 1. 
gravouslyt, adv. Seriously; by grave consid- 
erations. 
The erle . . . grauoualy perswaded the magistrates of 
the citees and tounes, and gently and familiarly vsed and 
tracted the vulgare people. Hall, Hen. IV., an. 1. 
gravy (gra'vi), .; pi. gravies (-viz). [For- 
merly (16th century) spelled greavy, greavie; < 
ME. grave (2 syllables) ; origin uncertain ; ap- 
par. orig. an adj., < graves, greaves, the sedi- 
ment of melted tallow: see graves 1 , greaves.] 
The fat and juices that drip from flesh in cook- 
ing; also, these juices made into a dressing for 
the meat when served. 
There are now at fire 
Two brests of goat : both which, let Law set downe 
Before the man that wins the dayes renowne, 
With all their fat and greauie. 
Chapman, Odyssey, xviii. 
To stew in one's own gravyt, to be bathed in sweat. 
Compare to fry in one's oivn grease, under grease. 
He relieved us out of our purgatory [a bath], and car- 
ried us to our dressing rooms, which gave us much refresh, 
ment after we had been steiring in our own gravy. 
London Spy (1709), ix. 219. 
gravy-boat (gra'vi-bot), n. A small deep dish 
for holding gravy or sauce, especially such a 
dish with a handle at one end and a long spout 
at the other, the whole vessel having an un- 
symmetrical shape; hence, by extension, any 
vessel for holding gravy or sauce, 
gray, grey (gra), a. and n. [I. a. < ME. gray, 
grey, grei, greg, etc., < AS. grteg = OFries. gre 
= D. graauw = MLG. grawe, gra, gran, LG. gran 
= OHG. gra, MHG. gra (grow-), G. grau = Icel. 
grar = Sw. grS, = Dan. graa, gray. Not con- 
nected with G. greis, a., gray (with age), greis, 
n., an old man (see grise^, grizzle^-), nor with Gr. 
y/ialof, old, nor with ypala, an old woman. II. n. 
< ME. gray, grey, etc., miniver, grave, grey, a 
badger; from the adj.] I. a. 1. Of a color 
between white and black, having little or no 
positive color; and only moderate luminosity ; 
of the color of black hair which has begun to 
turn white, as seen at some distance. 
Is na your hounds in my cellar 
Eating white meal and gray 
Lord Randal (A) (Child's Ballads, II. 26). 
Yon gray lines 
That fret the clouds are messengers of day. 
Shak., 3. C., ii. 1. 
Thus sang the uncouth swain to the oaks and rills, 
While the still morn went out with sandals gray. 
Milton, Lycidas, 1. 187. 
When Life's Ash-Wednesday comes about, 
And my head's gray with fires burnt out. 
Lowell, To C. F. Bradford. 
2. Having gray hairs ; gray-headed. 
"A year hence, a year hence." 
"We shall both be gray." 
Tennyson, The Window, x. 
3. Old; mature: as, gray experience. 
Who pious gathered each tradition gray 
That floats your solitary wastes along. 
Scott, Don Roderick, Int., st. 5. 
Common gray goose. See goose. Gray antimony, 
stibnite. Gray copper, gray copper ore, the mineral 
tetrahedrite. Gray cotton, gray goods. See colttmi. 
Gray crow, gray duck. See the nouns. Gray falcon. 
See peregrine, n. Gray fox. See/ari,l. Gray Friars. 
See Franciscan. Gray goat's- beard, grouse, gull, 
hepatization, jay, kingbird, etc. See the nouns. 
Gray manganese ore. Same as manganite. Gray 
mare. See more. Gray ore, in mining, the common 
designation of the vitreous copper ore, or vitreous sulphid 
of copper; the chalcocite of the mineralogist. Gray 
owl, phalarope, rabbit, shark, snapper, snipe, etc. 
See the nouns. Gray oxid. Same as blade -tvrpeth. 
Gray sour, in calico-bleaching, an operation following the 
lime-boil, consisting in washing the pieces in dilute hy- 
drochloric acid. The insoluble lime-soaps are decom- 
posed, and the lime is removed, other metallic oxids pres- 
ent are dissolved out, and the brown coloring matter is 
loosened. Also called lime-sour. Gray squirrel, whale, 
wolf, etc. See the nouns. 
II. n. I. A gray color or tint ; a color having 
little or no distinctive hue (chroma) and only 
moderate luminosity. If only about 6 per cent, of 
the light is reflected, the surface is called black; if as much 
as 50 per cent, is reflected, it is called white. Pure gray 
has a slightly bluish appearance, owing to contrast with 
the color of brightness which enters Into the sensation 
produced by white light. A small admixture of red with 
gray light makes the modified gray called ashes of roses. 
A small amount of green light mixed with gray is not no- 
ticed, and if the mixture is placed in juxtaposition with 
pure gray, the latter looks pinkish by contrast, while the 
former appears of a neutral tint. A larger admixture of 
green will give a mouse-gray (which properly requires the 
green to be yellowish^ a still larger amount an olive gray, 
and still more a sage green. The effect of the admixture 
of violet blue is singularly dependent upon the shade of 
gray ; if it is quite light, the result is a lilac gray or full 
