The document discusses various topics related to surveying including chain surveying, compass surveying, traversing, prismatic compasses, bearings, latitude and longitude, and compass adjustments. It provides information on when different surveying methods are recommended based on terrain and area size. It also defines key terms like meridians, bearings, declination, inclination, and different bearing systems. Examples are given for calculating bearings and adjusting for magnetic attraction. Adjustments discussed for prismatic compasses include centering, leveling, and focusing the prism.

1. (Dr. M K Manik)
HOD.mechccetb@gmail.com

2. Surveying
Chain Surveying can be done when the
area of the surveying is
Area is flat/level to the ground
Comparatively Small
compass surveying is recommended
But when the area is large
There are large many hindrance to pull the
chain

3. Traversing
Traversing is the frame work consist of
connecting lines
The line are measured by the chain or tape
Direction are measured with the help of angle
measuring
devices called compass
Compass surveying direction are measured by
compass
and distance are measured by tape or chain

4. Compass survey
A prismatic compass is used for navigation and for
surveying instrument
which is extensively used to find out the
bearing(Angle) of the traversing and included
angles between them,
Compass surveying is a type of surveying in which the
directions of surveying lines are determined with a
magnetic compass,
 And the length of the surveying lines are measured
with a tape or chain or laser range finder

5. Prismatic compass

6. The compass is generally used to run a traverse
line.
The compass calculates bearings of lines with
respect to magnetic north
The included angles can then be calculated using
suitable formulas in case of clockwise and anti-
clockwise traverse respectively
For each survey line in the traverse, surveyors
take two bearings that is fore bearing and back
bearing which should exactly differ by 180° if local
attraction is negligible
 The name Prismatic compass is given to it
because it essentially consists of a prism which is

7. definition and types of meridian
 A circle of constant longitude passing through a
given place on the earth's surface and the terrestrial
poles
A meridian is an imaginary line from the North Pole
to the South Pole.
Meridians are drawn on maps to help you describe

8. The meridian through Greenwich (inside Greenwich
Park), England, called the Prime Meridian, was set at
zero degrees of longitude, while other meridians
were defined by the angle at the center of the
earth between where it and the prime meridian cross
the equator
Latitude is distance north or south of the equator
(an imaginary circle around the Earth halfway
between the North Pole and the South Pole)
and longitude is distance east or west of the prime
meridian (an imaginary line running from north to
south through Greenwich, England).

10. Earth and its latitude and longitude

11. Description of a chain

12. Metric chains

13. Inclination and Declination

14. Bearings
BEARINGS AND AZIMUTHS: Horizontal angles are
angles measured in a horizontal plane by a level
instrument
 Used to determine: the locations of points. the
orientation of lines.
The units of measurement most commonly used
in surveying is the hexadecimal system based on
degrees, minutes, seconds.
The bearing of a point is the number of degrees in
the angle measured in a clockwise direction from
the north line to the line joining the centre of the
compass with the point
 A bearing is used to represent the direction of one

15. Bearing and Explanation

16. Designation of bearing
Whole circle bearing (W.C.B) Or Azimuthal system
In this system bearing
of a line is measured
with magnetic North ( or
with south)
 In clockwise direction.
 The value of bearing
thus varies from zero
degree to 360 degree
Prismatic compass is
graduated on this
system
 In India and UK the
WCB is measured
clockwise with magnetic
north.

17. Quadrantal Bearing(Q.B.)
In Q.B system quadrant are marked as bellow

18. How the angles are marked in both
the system

19. Quadrantal Bearing(Q.B.)
In this system bearing of
a line is measured East
ward or west ward from
North or South which ever
is nearer.
Both North and South
are used as reference
meridians
 The direction can be
either clockwise or
anticlockwise depending
upon the position of the
line.
 In this system therefore,
the quadrant, in which the
line lies, will have to be
mentioned.

20. Various type of lines used in surveying

22. For 2nd quadrantFor 1st Quadrant
(1) For the first
quadrant
the W.C.B will
be equal to
R.B. because
both of them it
starts from the
north the
directions. for
R.B. direction
will be North to
East (NE)
W.C.B+R.B. = 180° SO [ R.B.=180°-
W.C.B.]
The directions for reduced bearing is
South to East (SE)

23. W.C.B.-R.B.=180°. SO R.B.=W.C.B.- 180°
The direction for reduced bearing is South to East (S
When the location is in the third quadrant

24. When the location is in the Forth quadrant
W.C.B.+R.B.=360° SO R.B.=360-W.C.B.
The direction for reduced bearing is north to west (NW)

25. Problem-1
The following interior angles were measured with a sextant in
a
closed traverse, the bearing of the line AB was measured as
60°00´
with prismatic compass. Calculate the bearing of all other line
if A=140°10´; B= 99°8´; C=60°22´ ;D=69°20´
Solution:
To find the bearing of a line = The
measured clockwise angle to the bearing
of the previous line + Include angle
between the line and previous line (In
clockwise direction) - 180°
Then Bearing of line AD = clockwise bearing of line
AB + include angle between
BA and AD
i.e. 140°10´ - 180°
= (60° + 180) + 140°10´ ± 180
= 200°10´

26. Problem-2
The magnetic bearing of the line AB is 28°30´ E. Calculate the true bearing if
the declination is 7°30´ West.
Solution of the problem will as
** Angle of AB line from TS
e.i. Equal to 28°30 ´ + 7°30´ = 36°00´
Hence True bearing can be written as
= S 36°00 E

27. Problem-3
The following bearings were observed while traversing with a compass .Mention
which stations were affected by local attraction and determine the corrected
bearingsLine F.B. B.B. Line F.B. B.B.
AB 45°45´ 226°10´ CD 29°45´ 209°10´
BC 96°55´ 277°05´ DE 324°48´ 144°48´
To find out the magnetic attraction any point is to be calculated that
Fore / Back bearing - Back/Fore bearing = 180°
In the above problem only at the line DE has FB- BB= 180°, in this line there is
no attraction
But other all the lines are under magnetic attraction as the subtraction value is
other than 180°. It also suggested that as line DE has no attraction hence at the
point D as well as E has no attraction also
Line F.B. B.B. Line F.B. B.B.
AB 45°45´ 226°10´ CD 29°45´ 209°10´
no attraction
As per
suggested
BC 96°55´ 277°05´ DE 324°48´
no
attraction
144°48´
no attraction

28. Line F.B. B.B. Line F.B. B.B.
AB 45°45´
225°45´- 180°
=45°45´
226°10´
25´=225°45´
CD 29°45´
209°10´-
180°
-29°10´=35´
209°10´
no attraction
As per
suggested
BC 96°55´
276°30´- 180°
96°30´ =25´
277°05´
-35´
=276°30´
DE 324°48´
no
attraction
144°48´
no attraction
** Rule to calculate bearing F.B. - B. B = ± 180°
*It clearly define that in CD line D point is out of magnetic attraction but point C is
under attraction
If No attraction is there in the line CD the B. B – F.B = 180° i.e. 209°10´ - 180° =
29°10´ so
F. B. at point C will be 29°10´, but due to attraction it is 29°45´, Hence 29°45´ -
29°10´= 25´ is subtracted from this bearing to get bearing with out magnetic
attraction
•Similarly that 35´ is more with point C at 277°05´, that will be corrected as
277°05´- 35´= 276°30´
•Hence at point B corrected as 276°30´ - 180° = 96°30´ by subtracting 25´ from the
attracted bearing. Again point B of AB has 25´ more in bearing with 226°10´.
•To make it correct 25´ is to be subtracted from the given bearing and it will be
226°10´ - 25´= 225°45´

29. Adjustment in Prismatic compass
The following adjustment are necessary in the piezometric
compass
a) Station or Temporary adjustments
i) Centering ii) Leveling iii) Focusing the prism
b) Permanent adjustments
 The permanent adjustment of prismatic compass are
almost the same as that of the surveyor’s compass
except that there are no bubble tubes to be adjusted and
the needle can not be straightened.
 The sight vanes are not adjustable

30. i)Centering
Centering is the process of keeping the instrument exactly
over the station
Ordinarily prismatic compass is not provided with fine
centering devices as is generally fitted to engineers
theodolite.
The centering is done by adjusting the legs of tripod
A plum bob may be used to judge the center if it is not
available, it may be judge by dropping a pebble from
the center of the bottom of the instrument
ii) Leveling
If the instrument is a hand instrument, it must be held in
hand in such a way that the graduated disc is swinging freely
and appears to be level as judged from the top edge of the
case.
Generally a tripod is provided with ball and socket
arrangement with the help of which the top of the box can be
leveled

31. Thank youTo
all