1 - NGA

etween We points not et the earns fevel
retstive to a spadfii datum.
davo staflon-l%at *alien in a given system
of stetiena that is cxmtrofbd trf the meater
station. Also called remote station.
divwa+digifaf) Pofyws formed when two
diimftt ~fw.a do W *@ abng e single
mrnrrmn ne and leave e smell SOSCa between
the fargertwo.
xdopa angle-The angle between a dope and
the horizontal.
slope chalnlng—See slop. taping.
slope correction of tape-See grade
correction.
slope correction-l. (hydrography
surveying) Tha correction applied to soundings
ermneoudy fxieilionsd as a resuft of an echo
smmdar rese”wing its initial return from a point
upslopa frem its racerdad position. 2. (Isnd
surveying) See grada correction.
slope taping-Taping wherein ‘the ‘Iapa” (or 4
chain) is hakd .s raquired by the sbpa of the
ground, the slope of the tape measured, and
the horizontal distance computed. Also cslled
.Iope chalnlng.
Elope—See gradient.
slot cutter-See templet cutter.
slotted templat—A Iempiet on wh}ch the
radtals are represented as a slot cut in a sheet
of cmdboard, metal, or othar material.
slottod-templet plot—See @lotted.
templet triangulation.
slotfad-tamplet triangulation—A graphical
radial triangulation made by the use of slotted
templets. Also called slottad-tamplet plot.
Small Wettad Area Twin Hull (SWATH)—
A vessel designad for stability by having ils
buoyant volume rrmstly underwater, presenlly
being avaluatad for use in hydrographic
surveying projests.
small circle-A circle on the surfaca of the
Earth, the plane of which does not peas through
the Earth% center,
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smell-ecale map-A map having a ecsle of
1:Soo,olx or Smsfler.
smooth ●haet-A final pbf o! fmfd corrlrd end
hydrugraphc devebprnent such as courrdings,
fathom curves, wire drag arass, etc., to b. used
in chart mnetrucf ion.
amoothlrrg-1. A sat ef pmceduraa for
removing short-range, errzdic variat”mna from
lines, aurfasm, or date series. 2. (itige
prcca~ng) The avereging of dansitk in
adjscanl ar~s to produce more gradual
transitii.
srrakosllp-see ●tch slip.
snap markar—See point marker.
Small’a law of refractloxThis law states
that the sin. of the angle of incidence divided
by the sine of the angle of refraction equefs a
mnstant termed the index of rafrectiin when
one ef tha media is air. The index C4 refraction
can also be .xpIainad as the ratio of the vafocily
of light in one medium to thst in anothar.
. . . . .. .. .. . .
aoftcopy —Products which are maintained in
digital fomrst for use with automsted data
processing equipment.
solar rdtltude-Angular distanse of the Sun
above the horizon.
solar attachment-An auxiliary instrument
which may h attachad to an engineer’s transii,
parmitthg k u= as a solar oornpaes.
solar day—1. The duration of one retation of
the Earth on ifs axis, with respect to the Sun.
This may be either a maan eefar dsy, or an
apparent solar day, aa the referance is the
mean or apparent sun, re6pectWety. See also
.ePparent solar day; moan solar day. 2.
The duration of one rotatkm 04 tha Sun.
solar declination—Angular dktarwe of the
Sun expreasad in degrees nerth or aoufh d the
celestial aquatoc it is indicated as “+” wften
north and .-. whan south of the Equator. Also
called dcrclirretlon of the Sun.
solar ●cflpse mathod—A means of
determining the angular distanca betwean two
observers along tha canter fine of fhe path of a
aolsr .dipaa.