 SIYG.TXT       Glossary of Surveying Words                                  61

                                   Chapter G

                          Glossary of Surveying Words

Abney level: A hand held instrument for measuring inclination precise to about
0.2 degrees.  There are several manufacturers.  Cost about $75 to $150.

Acre: 10 square chains. 43560 square feet.

Aerial photo: A photograph taken straight down from a high altitude airplane so
that the photo looks like a map.

Are: Pronounced "air".  100 square meters.

Azimuth: The common method of giving compass directions, whereby a full circle
is divided into 360 degrees, starting at North and turning clockwise.  I'm told
that this doesn't apply in the Southern Hemisphere.

Backsight: Instrument readings taken to the FROM station, from the TO station,
but recorded as if the sight were taken normally.

Blunder: A BIG mistake, obvious and correctable.

Brunton pocket transit: A sighting compass precise to about 0.5 degree.
Brunton makes the original; there are several imitators.  Also known as Army
Artillery Compass when graduated in gradians to confound The Enemy.  Cost:
about $200.

Cardinal direction: Any one of the four directions; North, East, South, or
West.

Chain: 66 feet.  4 rods.

Clinometer: Inclinometer.  A device to measure inclination.

Closure Error: When surveying in a loop and making the ending station the same
as the beginning station, the calculated distance between these two stations.

Compass direction: A direction from one station to another station, measured as
azimuth.

Corner: A point on a property boundary, established to define that boundary.

Cosine: Abbr. COS.  Pronounced "cosign".  A mathematical function of an angle,
equal to the adjacent side divided by the hypotenuse (longest side) of a right
triangle containing that angle.


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Declination: The angle difference between the compass direction towards
Magnetic North and that towards True North.

Degree: The three hundred sixtieth part of a full circle.  1 = 1/360 of a
turnaround.

Departure: What professional surveyors call the east distance.

Elevation: The distance above (or below) an arbitrary zero level.

Error: The difference between a measured value and reality.

Forester's Compass: Staff Compass.  A surveying compass precise to about 0.2
degrees.  Cost: $400.

Furlong: 10 chains.  660 feet.

Gradians: A method of giving compass directions, whereby a full circle is
divided into 400 gradians, starting at North and turning clockwise.  The Army
uses this to confuse The Enemy.

Hectare: 100 ares.  10000 square meters.  2.47 acres.

Inclination: The angle in degrees between a line of sight and horizontal.  Up
is +, down is -.

Inclinometer: Clinometer.  An instrument to measure inclination.

Land description: The written definition of a piece of property.

Latitude: What professional surveyors call the north distance.

Legal description: A land description typed by an attorney's secretary.

Lensatic compass: Also known as the Army Marching Compass.  A diabolically
engineered compass graduated in bassackwards whatchamacallits in order to
totally confuse The Enemy.  Precise to about 10 degrees.  Cost: about $10.

Line: A part of a property boundary between two corners.

Link: A hundredth part of a chain, 0.66 feet.

Magnetic North: The direction towards the Magnetic North Pole.  This is where
the compass needle points.

Minute: The sixtieth part of a degree. 1' = 1/60  60' = 1


 SIYG.TXT       Glossary of Surveying Words                                 63

Pace: The distance covered in one step.  Usually between 2.5 and 3.0 feet.
1000 double paces of 2.64 feet define the mile as 5280 feet.

Perch: A rod, a pole, 16.5 feet.

Percent closure error: The closure error divided by the run times 100%.

Plat: What professional surveyors call a map.

Pole: A rod, a perch, 16.5 feet.

Quadrants: An archaeic method of giving compass directions, utilized to
simplify the arithmetic B.C. [Before Calculator]  Presently used to keep
landowners stupid.

Radians: A mathematical method of measuring angles, used by some calculators,
computers, and pure mathematicians.  A Radian = 57.2957795131 degrees.

Ranger: A sighting compass imported by Silva Compass, precise to about 1
degree.  Cost: about $41.

Rod: A perch, a pole, 16.5 feet.

Rood: 40 square rods, perches or poles.  10890 square feet, one quarter acre.

Rope: 20 feet.

Run: The distance surveyed since an arbitrary starting station.

Second: The sixtieth part of a minute. 1" = 1/60'  60" = 1'

Sine: Abbr. SIN.  Pronounced "sign".  A mathematical function of an angle,
equal to the opposite side divided by the hypotenuse (longest side) in a right
triangle containing that angle.

Square perch: A square rod, 16.5 * 16.5 = 272.25 square feet.

Staff Compass: Forester's Compass.  A surveying compass precise to about 0.2
degrees.  Cost: $400.

Station: A place where surveyor's measurements are taken.

Stringbox: A distance measuring instrument which operates by measuring a thread
pulled from it.

Tape distance: A distance from one station to another, usually measured in
feet.

 SIYG.TXT       Glossary of Surveying Words                                 64

Theodolite: A surveying instrument which can measure the angle between two
directions, as well as the angle between a direction and Magnetic North.
Precision: about 0.01 degree.  Cost: $thousands.

Topo map, topographic map: A map showing the shape of the surface of the land.
In the United States, usually a 7.5 minute map at 2000 feet per inch showing
all surface features.  Cost: about $3.

Transit: A surveying instrument, similar to a theodolite, which can measure the
angle between two directions, as well as the angle between a direction and
Magnetic North.  Additionally, the sights can be easily turned around
(transited) to obtain a backsight.  Precision: about 0.01 degree.  Cost:
$thousands.

True North: The direction towards the North Pole.

: Degree symbol if you can read full ASCII.

': Minute symbol.  Also foot sumbol.

": Second symbol.  Also inch symbol.

Another last chance to tell you to take precise compass readings, with a double
check and a backsight.  Nearly all your error is in the compass with the poor
man's method of land surveying.

If there are any other surveying words which you think that I should define
here, then tell me them.


Dave Beiter
CAVE, Inc
1/2 Fast Road
Ritner, KY  42639

606/376-3137 (everytime)

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