Graphics Reference
In-Depth Information
sense of them, and a few ideas for their visual representation. Perhaps more impor-
tantly, one can see this century as giving rise to the beginnings of visual thinking, as
illustrated by the examples of Scheiner and van Langren.
1700-1799: New Graphic Forms
1.2.3
With some rudiments of statistical theory, data of interest and importance, and the
idea of graphic representation at least somewhat established, the
th century wit-
nessed the expansion of these aspects to new domains and new graphic forms. In
cartography, mapmakers began to try to show more than just geographical position
onamap.Asaresult,newdata representations (isolinesandcontours) wereinvented,
and thematic mapping of physical quantities took root. Towards the end of this cen-
tury, we see the first attempts at the thematic mapping of geologic, economic and
medical data.
Abstract graphs, andgraphs of functions became morewidespread,along with the
early stirrings of statistical theory (measurement error) and systematic collection of
empirical data. As other (economic and political) data began to be collected, some
novel visual forms were invented to portray them, so the data could 'speak to the
eyes.'
For example, the use of isolines to show contours of equal value on a coordinate
grid (maps and charts) was developed by Edmund Halley (
).Figure
.
, showing
isogons - lines of equal magnetic declination - is among the first examples of the-
matic cartography, overlaying data on a map. Contour maps and topographic maps
were introduced somewhat later by Philippe Buache (
) and Marcellin du Carla-
Boniface (
).
Timelines, or 'cartes chronologiques,' were first introduced by Jacques Barbeu-
Dubourg in the form of an annotated chart of all of history (from Creation) on a
-
footscroll(Ferguson,
).Joseph Priestley,presumablyindependently, usedamore
convenient formtoshowfirstatimelinechartofbiography (lifespans of
famous
people,
B.C.toA.D.
,Priestley,
),andthenadetailedchartofhistory
(Priestley,
).
heuseofgeometricfigures(squaresorrectangles)andcartogramstocomparear-
easordemographicquantitiesbyCharlesdeFourcroy
(
)andAugustF.W.Crome
(
) provided another novel visual encoding for quantitative data using superim-
posed squares to compare the areas of European states.
As well, several technological innovations provided necessary ingredients for the
production and dissemination of graphic works. Some of these facilitated the repro-
duction of data images, such as three-colour printing, invented by Jacob le Blon in
, and lithography, invented by Aloys Senefelder in
. Of the latter, Robinson
(
, p.
) says “the effect was as great as the introduction [of the Xerox machine].”
Yet, likely due to expense, most of these new graphic forms appeared in publications
with limited circulation, unlikely to attract wide attention.
Image: http://math.yorku.ca/SCS/Gallery/images/palsky/defourcroy.jpg
