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Boston Iavollng rod-A two-piece rod with
fixed ta~l on one end. The target k adjusted
in elevation by moving one @ of the rod on
\ the other. Ra@ by Vemter. FOr negnls greater
than 5 1/2 teal, the target end is up; for lesser
heighls, the target end is cbwn.
MIL-HDBK-850
Bottom Ccmtour Charts (BC)--Charts
depicting detailed underwater topography In the
term of bathymetric cuwes. BCS provide a
general picture of the saafkror and ifs features,
portrayad horn survey data and fore)gn
published charts. Deeigrwd for the use 01
aubmarhe.e or ships by the method of bottom
GOIIfOUr matching.
Bouguer ●omaly-A difference barwean an
observed vatue of gravtfy and a theorel”cal value
at the Foinf of observatbn, which has been
corrected for Ihe elfacf 01 Topography and
efavalion only, Iha topography baing considered
as a pfafe of indefinite axfent.
Bouguer corractlon-A correcfiin made In
gravity work to take amount of the allitude
(elevaliorr) of the station and the density of the
mess between an infiniie plane though the poinl
of observation and the infhsire plane of the
reference elevation.
Bouguer plma-An imagh’rary layer of infinite
Ienglh and of thickness eQual to the height 01
the observation point above \ha reiarance
aurtace (Wualfy the gaoid). In a~lying the
Bouguar corrac3ion, the afrracring layer lessens
me free air effect.
Bouguar raductlon--Geophy sically, fhe
Souguer reduction removes all masses above
fhe reference arsrfaca (usually tha geold) and
then reduces the gravffy from tha tarraln to the
referenca eurfaca.
boundary (d* lacto)-An International or
administrative bwndary whose existence and
legality are not recognized by an csxrcemad, or
are not defined by appropriate documents, but
whlsh is a praabal dk+sion bahveen separate
natiinal or provincial administering authorities.
boundery (de jure)-An ktternalional or
admlniafrative bowdary whose axistenca and
legality are racognlzad.
boundary dlscontlnultles—Ditlerent
alevallon values for common DMA standard
digital terrain elevatbn data (DTED) malrlx
points In adjacenf data files.
boundaw llna-A iine of demarcatbn
belween contiguous poliiical or gaographal
enfltlas. The word %oundary. is SOITB times
omitted, as in “afata Iiie”: some times tha word
.Iine- is omitted, as in “infematicmai boundary,-
“counfy boundary,” efc. The term tsoundary
Ilno la usually appliad to fmundaries befwaen
pofiii territories, and %tate boundary tiia~
bafween two atatas. A boundary line between
prkately owned parcels of land Is taMWd a
propeny Ilna by preference, or if a line of the
Unked Slatas public land surveys, la given lfM
pa~buiar dasignafiin ot that survey systam, as
“sesfion Iina,- %wnahip fine,. elc.
bounde~ map-A map prepared specifically
tor the pu~sa of delineating a boundary Iina
and adjacent territory.
boundary monumant—A material object
placed on or near a boundary tine to presewe
and ktenfify the location of the boundary fine on
tha ground.
bounda~ point e.veraglng-Averaging the
elevations of mmmon poinls fmm two dfilerenl
data sets and reassigning each the average
value; or resolving a discraparq between IWO
elevalbns tor a common poinf by arslgning tha
avarage elavalion vah.m to that polnf.
boundary point waightad ●veraglrtg—
Reaotving a diacrapancy bafwaen a aaries of
overlapping elevations from two dma sats by
biasing one data set utiliuing eithar tha amuracy
01 a data set or the relative dbtance to lhe edge
ot the data.
boundary survey-A survey made 10
aslabfish or to reestablish a boundary fine on
the ground or to obtain data for rxmstrusting a
map or plat showing a brxdary line. The term
boundary survey is usually raslrictad to
surveys of boundary fines berwean poliibel
territories. For the survey of a boundary line
behveen privately owned parcels of land, the
tarm land survey is praterred: except In
United States public land auweys fhe term
cadaatral survey Is used,
boundary vista—A lane cleared afong a
boundary line pasaing through a wooded area.
Bowle affect-The Irtdirecf effeci on Qravlfy
due to the warping of the gaoid, or the elevaflon
of the gaoid with respea to tha spheroid of
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