Geography Reference
In-Depth Information
The basic function of maps is to show how particular phenomena are distributed over all or
part of the world. In this chapter, for example, you will see maps of Canadian cities, languages
inSouthAmerica,andglobalmigrationtotheUnitedStates.Cartographers(mapmakers)com-
municate these and other kinds of information in part by incorporating into their maps a stand-
ard set of elements whose purpose is to help the map-reader get the message. They include the
following:
Title:
The title conveys the subject of the map and is the first thing a map-reader should look
for. Ideally, its wording is simple and accurate. If the title confuses you, then that is probably more
of a comment on the cartographer's communication skills than your intelligence quotient.
Legend:
Maps commonly convey information with the aid of symbols whose meanings
may be uncertain. Thus, the cartographer always provides a legend (or
key
) that contains and
defines the symbols found on the map.
Scale:
Scale (described more fully in the following section) provides information about
the actual size of the area shown on the map. Typically, this is achieved with a small ruler-like
entry on a map that equates distance in miles and/or kilometers with measurement in inches
and/or centimeters.
Orientation:
Orientation is the alignment of the map with respect to cardinal directions.
Which way are north, south, east and west? The standard rule of thumb is that north is towards
the top of the map, but not every layperson knows the rule and not every map follows it. Ac-
cordingly, many maps include a direction indicator, minimally a north-pointing arrow. While
one is included in Figure 5-1 for the sake of example, they are not common on maps of large
areas because cardinal directions may vary due to distortion (see Chapter 4). Also, if latitude
and longitude lines are included, then the cardinal directions are somewhat redundant.
Grid lines:
Many maps contain a couple of labeled grid lines of latitude and longitude in
order to convey the global context of the mapped area. If the cartographer has reason to be-
lieve that the map reader is intimately familiar with the mapped area, or if previous maps have
indicated the global context of the mapped area, then grid lines may be omitted.
Source:
Out of courtesy and honesty, cartographers commonly provide the source of the
information conveyed on the map. This is especially true for maps that portray numerical data.
On the other hand, some subjects are generally considered “common knowledge” and do not
require source citation. Examples include maps of countries, physical features, and climates.
