Interpretation of toposheet

1. 1) MAP:
A map is a two dimensional surface drawn on a flat paper or sheet with length and
breadth. All physical and cultural features are shown on the map with the help of certain
symbols (conventional signs). A map is graphical and conventional representation of the
distribution of physical and cultural phenomena of the earth surface drawn to a scale or
representation of natural and man made features are plotted on a paper or a sheet with a
scale is called a map.
2) SCALE:-
A scale denotes the relationship between the length of a line on the map or sheet or
paper and the length of that line on the ground.
It is defined as the ratio between the distance between the two points on the map and
corresponding distance on the ground. Large areas can be drawn on small sheet of paper
with the help of a scale. Scale helps us to know the distances on the map. The ratio of a
scale can be expressed in three ways
A) By a statement or verbal scale.
B) By an arithmetical representative fraction (R.F)
C) By liner or graphical scale.
A) VERBAL SCALE OR DIRECT STATEMENT: -
Verbal scale gives the map and the ground ratio through a statement.
Ex. One inch to four miles.
It is evident from this example that one inch on the map represents four miles on the
ground. Such scale is very simple and readily understood. A verbal scale involves a
statement expressing the relationship between the map and the ground through particular
type of measurement system. Such system may differ from one country to another.

2. B) REPRESENTATIVE FRACTION(R.F): -
It is popularly known as scale or ratio between the map and ground is expressed in the
form of an arithmetical ratio or fraction in which the map is represented by the
numerator which is always one and the ground by denominator which is an equal
number of similar units. Ex. 1cm:100 meters, 1inch:1000ft.
This scale can be denoted as 1/100 or 1/1000 = 1:10
C) LINEAR OR GRAPHICAL SCALE: -
It is a straight line of convenient length. It is divided in to equal division of 1 inch
representing 1 mile.
0 1 2 3
0 1 2 3
The
figure ‘0’ is not placed at the extreme left hand end but at right hand end on the first
division.

3. GRID REFERENCE:
Four figure grid reference consists of four digits. The 1st two digits are of easting
and last two digits are of northing. The Eastward lines or vertical lines drawn on the
survey sheets are called Easting. Northward lines or horizontal lines drawn on the survey
sheets are called Northing.
A network of easting and northing forms number of squares called Grids. The left hand
corner of the grid represents each grid for reference. Easting are always quoted first then
northing. These lines are black or red in colour.
Easting
Northing
N
S
EW
N
W
N
E
S
W
S
E

4. EXTENT OF THE MAP: -
LONGITUDES: - The lines of longitudes are called meridians. They are imaginary
lines or semicircles drawn on the earth surface in north/ south direction. The word
meridian being derived from a Latin word meaning Mid-day. All places on the same
meridian of longitude have mid day at the same day. The earth circumference consists of
360º so we can draw 360º longitudes. The meridian or longitude passing through the
Greenwich is 0º and is called standard meridian or prime meridian. All other degrees of
longitude are drawn to the East or West of the prime-meridian. There are 180º of
longitudes towards East or East longitude and 180º towards West or West longitude. The
180º is common for East or West. Each degree of longitude cuts the latitude at the right
angle ie, 90º
W E
E
W
N
S

5. LATITUDE:-
Lines of Latitude are the circles drawn round the earth parallel to the equator. The
parallel of latitude is an imaginary circle drawn east /west on the surface of the earth.
The circle of latitude that divides the earth in to two hemispheres and is exactly at equal
distance from the pole is called equator. The other circles of latitude are drawn to the
North or South but parallel to this circle. As the earth is a sphere the angular distance
from the equator to the pole is 90º so we have 90º of latitude from the equator to the
North pole in the Northern hemisphere. 90º of latitude from the equator to the South
pole in the Southern hemisphere. All the degrees of latitudes are circles except the poles
which are mere points or straight line. All these circles are parallel to each other and to
the equator. They are equi-spaced or the distance between any two consecutive degrees
of latitudes is the same.
N
S
W
0
0
EEqu
ator
Latitu
de

6. COLOUR REPRESENTATION IN THE MAPS -
Various colours are used to show different features on the survey sheet.
Yellow colour- represents cultivated area
Green colour- represents forest.
Blue colour- represents water bodies
Black colour- represents boundaries and railway lines
Brown colour- represents contour lines and sand dunes.
Red colour- represents buildings and roads.
Prominent survey trees are black coloured.

7. RELIEF OR TOPOGRAPHY:
Relief or topographycan be shown on the map by
1. Hashing (without contours)
2. Hill shading (with contours)
3. contour lines
4. form lines
5. spotheights
6. triangular stations, BM (bench mark)
1. HACHURING – hachure are short lines representing the way in which water
would flow from high land to low land. On steep slopes they are closer together than the
gentle slopes, but on the flat ground there are none at all. It gives no indication of the
actual height. Both plateau and low plains are not shaded.
Hachuring gives modeled appearance and relief features stand out clearly.
2. HILL SHADING (WITH CONTOURS) – The steep slopes are then shown
by dark-shading. Plain lands and plateau are not shaded. Shading shows inclination or
slope of the ground. In non shaded area the ground is almost flat. It does not give actual
height and also which side is sloping either up hill or down hill side.
 Hill-shading gives modeled appearance of relief of light and dark shade.
3. CONTOUR LINES – A contour line is a line joining all places which are at the
same height above mean sea level. Or these are lines drawn on the sheet which join
together all the places having the same height above the mean or average sea level
(MSL). They are numbered and drawn in black or brown colour. All the contour patterns
on the map represents landscape, some relief features namely concaveslope, valley,
spur, ridge, escarpment and plateau, occurfrequently on the surface of the earth.

8. For representing relief features by contours it will be helpful to remember following
points.
 When contours are widely separated that indicates plane or table land or flat land with
gentle slope and when they are closely spaced they represent steep slope.
 They go on coming closer together all the slope become steeper and steeper until they
merge in to each other when the slope is almost vertical.
 Contours do not cross each other.
 A contour is a smooth line without numerous bends.
 They conform to the slope of the ground which they represent.
1. Uniform slope.
2. Concave slope.
3. Convex slope.
4. Terraced slope.
5. Undulating slope.
6. Conical slope.
7. Plateau.
8. V-shaped valley.
9. Spur
10. Escarpment.
4. FORM LINES –Sometimes accurate survey is not possible in hilly areas. Form
lines are used instead of contours. These are broken lines but not numbered. They help
to show minor details.
5. SPOT HEIGHTS OR BENCH MARKS - These are dots plotted on the
survey sheet showing the exact height of a point above the sea level. They are plotted
after actual survey of the area. These are shown in black colour. Ex: .200 or .BM200
6. TRIANGULAR HEIGHT OR TRIGONOMETRIC STATION – These
are plotted on the survey sheet in black colour and show the exact height of peaks after
actual survey of the area. These provide more accurate height with contours and spot
height. Ex. △200

9. SETTLEMENT PATTERN :
There are five types of settlement pattern.
1. NUCLEATED OR CLUSTERED - Buildings or houses are constructed in a
compactmanner and are very close to each other. Mostly near the wells or tanks or
bore wells etc.
2. SCATTERED OR DISPERSED - Buildings or houses are scattered
everywhere (isolated) away from each other.
3. LINEATED OR RIBBONED - Buildings or houses are constructed along the
road, river, canal or railway line.
4. RECTANGULAR PATTERN - Buildings or houses are constructed at cross
roads.
5. STAR-SHAPED PATTERN - Buildings or houses are constructed around the
big water bodies.
DRAINAGE PATTERN- There are five types of drainage pattern.
1. DENDRITIC PATTERN – A number of tributaries join the main river or
stream and make a pattern like veins of a leaf or branches of a tree or fingers on a
hand.
2. TRELLIS PATTERN(RECTANGULAR) - A number of streams and
tributaries join the main river at right angle. It looks like rectangular garden trellis.
3. RADIAL PATTERN – Streams and tributaries may flow in all directions from
the highest section. They flow out word forming pattern like spokes of a wheel.
4. PARALLEL PATTERN – streams or tributaries flow parallel to each other.
5. DISAPPEARING PATTERN - Streams and tributaries disappear in to the soil
before reaching the ocean or sea.

10. INTERPRETATION OF TOPOSHEET
1. Introduction
2. Relief or topography
3. Drainage
4. Mode of Transport
5. Settlement pattern
6. Climate
7. Vegetation
8. Occupation
1. INTRODUCTION-
1. The number of the toposheet given in the top right corner (Toposheet number).
2. Name of the area.
3. The district and state to which the area or map belongs.
4. Extent of the map ie. Latitudinal and longitudinal extent of the map.
5. Interval of parallel and meridian.
6. Extent of longitude and latitude.
7. Contour interval.
8. Total area in the given toposheet or total ground area.
9. Year of publication of the map.
10. Year of survey
11. Magnetic variation from the true north.
2. RELIEF OR TOPOGRAPHY -
The physical features include plains, plateaus, hills, valleys with respect to direction in the map.
Physical features can be interpreted based upon spacing of contour lines weather they are closely
spaced or widely spaced. The highest or height can be known from the Bench mark △ station or spot
height etc.
3. DRAINAGE-
Name of the river or stream, flow direction, height of the bank, breadth of the canal, stage of river,
meandering, River is seasonal or perennial, Drainage pattern, rock type. Appearance and disappearance
of stream. Variation in the breadth of the river or straem. Name of the tributaries joining the river.

11. 4. SETTLEMENT PATTERN –
Urban or rural
5. MODE OF TRANSPORT
Number of metal, unmetal, cart tracks, railway lines connecting one place to another.
6.OCCUPATION-
It is based on settlement pattern and mode of transport. If the map is yellow coloured the
occupation of the people is agriculture. In the area where irrigation is available from wells, tanks,
agriculture is intensive. If there is forest, some people may be engaged in burning of wood for making
charcoal and collection of forest products. In mining area occupation of the people is mining. In the
industrial belt,people will be industrial workers.
7. CLIMATE -
1. Coniferous trees suggest that climate is cool (Himalaya).
2. Deciduas vegetation indicates tropical or subtropical climate (dry and moist).
3. The presence of cactus, shrubs, dunes, virtual absence of streams suggest semidry climatic
condition.
4. Forest, bamboo, tea-garden, beetle palm suggest moderate to heavy rainfall.

12. Ex. Toposheet No :- 47k/3
1. Introduction
This map represents Poona, North Satara and Sholapur districts of Bombay state, Maharashtra.
Longitude – 74 0 – 75 45 East
Latitude – 17 45 – 18 0 North
Parallel and meridian – 5 & 5
Extent of the map - 15 by 15
Total area in the given toposheet – 324 sq. miles
Scale of the map – 1 inch to a mile or 1: 63,360 units.
The area was surveyed in the year 1954-55.
It was published by G.I.S. in the year 1957.
Magnetic variation from the true north is about 1 ¾ west 1953.
2. Relief
The map shows concentration of contours in the S-W direction of the map. The maximum elevation of
the hill is 2534’. Contour interval is 50’. Besides there are small hills. Densely spaced contours
indicate steep slope and is confined to S-W direction. The rest of the area is plain land or flat ground.
3. Drainage
The main river is Neera which shows meandering and is flowing from West to East. The river is in the
mature stage. Many tributaries joined the Neera river. Neera river and other small streams are the
main source of water in this region. There are wells and canals for irrigation purpose.
4. Settlement
Settlement is nucleated or clustered and scattered all over the area and is seen along the river
bank. The area is thickly populated. In the given toposheet the area is urban as well as rural.
5. Transport and communication
There are three metal and unmetalled roads. One metalled road connecting from Nateputa to Malsiras,
second road connecting from Malsiras to Pativasti, Malsira to Khundus. Unmetalled roads
connecting from Melsiras to Tirwandi and from Chitainagar to Umra.
6. Occupation
The occupation of the people is agriculture as well as industrial workers which can make out by the type
of settlement and relief or topography.