distance between the intervals. Using a ruler or virtually any device that corre-
sponds to the interval on the bar scale, a map user can then apply the distance on
the bar directly to the map and calculate the distance between twolocations.A
third method of indicating scale on a map is the representative fraction (RF),
which is reported as a simple ratio or fraction. A typical RF would be 1:250,000,
which might also be written as 1/250,000. This simple ratio informs the map
reader that one unit of distance on the map is equivalent to 250,000 in reality. An
advantage to using an RF to express scale lies in the fact that since it is a ratio,
any units may be employed, as long as they are consistent across the ratio. In other
words, a British scholar using the map might utilize miles in considering distances
and locations on the map, but her counterpart in France could use exactly the same
map and work in kilometers! Maps on which the scale is expressed as a
representative fraction therefore have a wider applicability, because someone
using the map can use any units to which she is accustomed.
Scale can also be used in relation to maps in a general sense. One may speak of
a “small-scale map” or, conversely, one may encounter a “large-scale map.” A
small-scale map is usually a map showing a relatively large area, perhaps a large
country, a continent, hemisphere, or even the entire world. The map is able to show
little detail, due to the scale at which it has been constructed. A small-scale map
also has a relatively small RF. A typical map of the world in an atlas might have
an RF of 1:100,000,000—this is clearly a small scale map, but an RF of
1:250,000 might be considered small scale as well, depending on the size of the
area portrayed on the map. A large scale map is a map of a relatively small area
that shows a considerable level of detail. The RF of a large-scale map is relatively
large, perhaps 1:50,000 or larger. A typical large-scale map might be a street map
of a small city, a map of a college campus, etc.
The concept of scale is also applied to the magnitude of spatial consideration a
given geographical study or argument may assume. This is sometimes called the
“geographical scale” of a study or research project, and may be conceptualized
at a variety of levels. For example, various scales of approach may be employed
in a comparative study—one might examine a specific geographical feature at
the global, regional, and local scales. A political geographer could investigate
the expression of political cooperation in afederation, a geographical alliance
that operates at a regional scale, while another political geographer might conduct
research on precisely the same topic but at the local scale, perhaps in the
government agencies of a single state or province. Geographical scale is an impor-
tant consideration when engaging in the study of any spatially expressed phe-
nomenon, because the scale at which research is performed often directs the way
in which a geographical space and its features are perceived and analyzed. Scale
affects how one views the world, engages the world, and understands the world.
Scale 297