1 - NGA

obtained. Also called concave
dlverglng lens.
lens;
negative mold—Tne cast resulling Irom
casting over a masler relief model.
negative ecrlbhrg—See scrlblng.
negative lltling—See tung.
negative-l. In black and white
phol~raphy an Image on film, plate, or
paper in which the normal tones of the
SUbjeCt are reversed. In color phcdography,
an image on film, plale, or paper, In which
cobra appear as lhelr complements. 2. In
Cartographic scrtbing, a scribed sheet is
essentially a manua[ly produced negative.
See also dupllcate negative; orlglnal
negetlve.
network enalysls—Analytical Techniques
mrrcemed with the relationships between
Imetions on a networlc such as the
cakulafion of optimal routes through road
networks, flow capacities of network
systems, or the best Iocalion for facilities
aiOW networks.
net—See euwey net.
neutral date—Digital Geographic
Information Ihal is inlended 10 supporl
numerous applications but must be tailored
for a specific application.
neutral filter—A filler Ihal reduces lhe
Infenslty of light reaching the film or plate
without aflectlng fhe tonal rendition Of
mlora In the original scene.
Naw York Ieveflng rod—A two-piece rod
wilh movable target. For heights greater
than 6 1/2 ieet, the target is clamped at 6
1/2 teet and raised by extending the rod.
Graduated to hundredths 01 a foot and
raad by vernier to thousandths.
MIL-HDBK-850
new ch&srt-A chart constructed to satisfy the
needs of navigation in a particular srea. If is
laid ouf in conformity with a broad scheme
10 meet future needs in fhe adjacent ereas,
new edl{lon-Confeins changes of such
importame to map or chart users lhal all
previous printings are made obsolete,
170
new survey—See resurvey.
Newton’s laws—l. (gravilalion) Every
parlicle of matter in the universe attracts
every other panicle wiih a !orce proporilonal
to the product of Ihalr masses and inversely
as the square o! the distance between
them. 2. (motion) (1) Every body continues
in its state of rest, or of uni{orm rndion in a
straight line, unless it is compelled to
change Ihaf stale by a force impressed
upon il. (2) The rate of change of
momen!um is propofilonal to Ihe Iorce
impressed, and takes the dkecfion of the
slraignl line in which the force acts. (3) To
every aclion Ihere is an equal and opposite
reaction; or, the mufual actions of two
bodies are always equal and oppositely
directed.
Newton’s rings—An interference effect
arising from close, bul nol quite pertecl.
conlact between Iwo surfaces, manifested
b~ irregular concentric rings of color.
Newlonlen constenf of gravltetlon—
See constenf of gravitation. .,
newton—The newton is the mefric (S1) unit of
force. A force of 1 newion (N) acting on a
mass of 1 kilogram imparts an acceleration
of 1 reeler per second per second. .One
newton equals 1 kilogram per meter per
second per second. See also dyne.
night efiect—(JCS) An ellecl mainly caused
by variations in the slate of polarization of
rellacted waves, which sometimes result In
errors in direction finding bearings. The
ellect is mosl frecfuenf al nightfall.
no-check poslfion—See IntersectIon
station.
nocturnel arc—See aatronomlc arc.
nodal Iine—in a tide area, tha fine about
which the Iida oscillates and where fhare is
little or no rise and fall of fha fida.
nodal plane—A plane perpendicular 10 tha
optical axis al a nodal poinl.
nodal point of emergence—See nodel
point, definition 1.