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INTRODUCTION

Traditionally, geography has always been concerned with the question of "where things are" - in other words, it is a subject that focuses on SPATIAL properties:

location, size (area), shape, distribution, boundaries, directions, pathways and distance

All of these properties lend themselves to MAPPING; MAPS are a fundamental tool of the geographer.

A map can be defined broadly as a representation to scale of features on the earth’s surface. The features may be tangible such as rivers or they may be abstractions such as political boundaries.

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The objective of the course is to provide a solid foundation in the basic principles of cartography. The emphasis will be on lab work using USGS topographic maps. Major topics include:

ProjectionsGrid systemsScaleElevationField surveys using a total stationField surveys using GPSThematic mapsIntroduction to GIS

Introductory cartography should include the history of the discipline – therefore, we start with a brief overview of major milestones in the history of cartography.

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Eratosthenes of Cyene (276-194 BC), a Greek scholar and head of the great library of Alexandria produced a map of the "known world", which included the important concepts of:- a spherical Earth- a circumference of 28000 miles (the actual value is about 25000 miles)- a grid of meridians and parallels (more on these later)

Eratosthenes made the first scientific attempt at measuring the size of the earth………

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Ptolemy’s world map AD 150.

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Claudius Ptolemy (AD 90-168) another Alexandrian Greek scholar. Ptolemy's contributions included:

- the theory and practice of making a world map

- the estimated latitude and longitude of some 8000 locations

- instructions for constructing 26 regional maps and 2 map projections (more on these later)

Ptolemy's insights had a profound influence on cartography for more than a thousand years, re-emerging in the late 15th century as an important foundation of modern cartography.

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Even as early as the Roman Empire, Ptolemy's ideas declined in favor of the idea of a flat disc Orbis Terrarum (a “T” in “O” map).

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With the fall of the Roman Empire and the coming of the "Dark Ages" much of the classical cartographic knowledge was lost to the western world and maps become dominated by the teachings of the Christian Church, resulting in maps of a flat Earth, with strongly developed religious themes given much greater significance than accuracy or informative content.

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Tower of Babel

Noah’s ark

13th century world map, Hereford Cathedral.

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This ended with the RENAISSANCE (14th, 15th Century Europe), due to:- rediscovery of Ptolemy's works- the expansion of ocean exploration/trade (required accurate maps for navigation).- magnetic compass

The result was the Portolan charts (Italian, 14th Century on).

These incorporated magnetic compass bearings, in the form of compass roses, but, significantly, did not include latitude and longitude or a map projection.

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The map is covered by Rhumb lines (constant compass bearing).

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The re-emergence of Ptolemy's work stimulated interest in

a. spherical Earth (GLOBES in use by 1492)

b. map projections

c. grids

Thus, 16th world maps were characterized by:

i. position related to meridians and parallels on a projection

ii. vagueness in lesser-known parts of the world

iii. major differences caused by choice of projection - this choice must still be made today.

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Ortelius World Map, 1570 (Note: latitude and longitude grid).

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The next step was the refinement, including

- larger scale

- more detail

- choice of features

- development of surveying techniques

- improving technology

(this brings us to the present day).