Chapter 1 Introduction to Map | class 11th | quick revision notes practical work in geography

Maps

• The shape of the earth is a shape
• A map, on the other hand, is a simplified depiction of an entire or part of the earth on a piece of paper. 3D to 2D
• The scale decreases because it cannot be drawn accurately
• Symbols, colors and shades are used
• Selective, symbolic and generalized representation of the entire, or a portion of the Earth՚s surface, on a plane at a low level
• Sketch is without scale
• Map with scale

Types of Maps

• Cadastral Map: A large-scale map drawn on a scale of 1: 500 to 1: 4000 to show property boundaries, with each number designated a parcel of land.
• Map series: A group of maps built on the same scale, style, and specifications for a country or region.
• Projection-map: The system of transformation of a spherical surface to a flat surface.
• Pay Scale: The ratio between the distance of two points on the map, the plan or photograph, and the actual distance between the same two points on the ground.
• Sketch Map: A simplified map that draws freehand that fails to preserve the actual scale or orientation.

Map Making Essentials

• Scale
• Map projection
• Map normalization
• Map design
• Map creation and production
• Scale – The scale of a map determines the extent of information content and the degree of reality with which it can be depicted on the map
• Map Projection – Simplified representation of 3D. Transformation of all sides-curved-geomorphic surface in one direction-conversion in directions, distances, areas and shapes
• Map Normalization – Purpose – Relief, drainage, vegetation, settlements; Select and simplify information
• Map Design – Selection of appropriate symbols, their shape and form, style of lettering, width of lines, selection of colors and shades, arrangement of various elements of map design within the map for map narrative
• Map making and production – first drawn with pen and ink and printed mechanically and now by computer

History of Map Making

• The oldest map was found in Mesopotamia, drawn on an earthen pillar that dated to 2,500 BC.
• Greek and Arab geographers laid the foundation for modern cartography – Earth՚s periphery and geographic coordinates in map-making
• Maps were drawn at various projections to obtain the correct direction, the correct distance, and to measure the area correctly.
• 19^th & 20^th Century – Aerial Photography + Exciting Map
• Mapping in India – Vedic Period
• In the classical treaties of Arya Bhatt, Varahamihir and Bhaskar, the expressions were crystallized into hant doctrines or laws.
• 7 biped by Indian scholars
• Mahabharata imagines a round world surrounded by water
• Sher Shah Suri՚s revenue maps further enriched the mapping techniques during the medieval period.
• Todarmal pioneered land surveying and mapping for revenue collection
• An intensive topographic survey for the preparation of an up-to-date map was taken with the establishment of the Survey of India in 1767, concluding in 1785 with a map of Hindustan.

Types of Maps Based on Scale

• Large-scale maps are produced to show smaller areas at relatively larger scales.
• Small-scale maps are drawn to show large areas.
• Large-scale maps: Large-scale maps are divided into the following types: (a) cadastral maps (b) topographic maps

a) Cadastral Maps: The word ‘cadastral’ is derived from the French word ‘cadaster’ which means ‘register of territorial property’ . These maps are designed to show the ownership of land property by demarcation of arable land and the planning of individual houses in urban areas. Keeping records of ownership as well as realizing revenue and taxes. Village 1: 4000 and city 1: 2000

b) Topographic maps: These maps are also prepared on a large scale. Topographic maps are based on accurate surveys and are drawn as a series of maps created by the national mapping agencies of almost all countries of the world. Pay scale of 1: 250,000, 1: 50,000 and 1: 25,000 – relief, drainage, agricultural land, forests, settlements

• Small Scale Maps: Contains wall and atlas maps

a) Wall maps: These maps are usually prepared on the basis of large size paper or plastic for use in classrooms or lecture halls. Atlas Map Scale < Wall Map Scale < Topographic Map

b) Atlas Maps: Atlas maps are very small scale maps. These maps represent large areas and provide highly generalized images of physical or cultural features.

Types of Maps Based on Function

• physical map
• relief
• Geologist
• Climate
• soil
• Cultural map
• Political
• The population
• Economic
• transportation
• Cultural maps show man-made features. These include population distribution and development, gender and age, social and religious structure, literacy, levels of educational attainment, occupational structure, location of settlements, facilities and services, transport lines and various maps showing the production, distribution and flow of various goods. Huh.

Use of Map

• Measurement distance
• Straight line by dividers
• Curved line is moved along the wheel path by thread or rotameter
• Measurement of direction
• Area measurement
• Measuring squares on illuminated table
• The direction is defined as an imaginary straight line on the map that shows a common base direction angular position. The line pointing north is the zero direction or the base direction. A map always shows the north direction. North, South, East and West. These are also called cardinal points.
• Area – The total number of ‘perfect squares’ is combined with the ‘partial squares’ .
• Area =
• The area can also be calculated using a fixed area polar circumference.

Polar Planimeter

• The area is also calculated using the Polar Planimeter. In this device, a measurement is made with the motion of a rod, whose position is constrained by fixing one end of the radial arc. The area to be measured is traced along its circumference clockwise with an index mark, starting at a vantage point at which the index of the tracing arm must return exactly. Reading on the dial before and after tracing the perimeter of the field will return a value in instrumental units. These readings are multiplied by the same constant to convert areas in square inches or centimeters by a special device.