I have been working with some mapping software, Google Earth and with ArcGIS, placing old maps onto satellite maps. Obviously, the old maps are inaccurate, but inaccurate in an interesting way. These cartographers produce a graphical representation that reflects their perception of the land, reflecting a human knowledge that satellite mapping cannot contain.
In Google Earth's "Featured Content" section, there is a 1733 map of North America (Rumsey Historical Maps) which is marvelously detailed and also remarkably out of scale. Some areas are foreshortened and twisted beyond recognition—Nova Scotia is grotesquely distorted, showing a basic misunderstanding of its shape and essential features. Other areas contain details which, while accurate, are out of proportion. For example, the area that Cooper uses as the setting for The Last of the Mohicans is out of scale, being larger than it is in reality (in the figure at the right, the yellow lines running diagonally up the image show the course of the Saint Laurence, which are considerably higher on the 1733 map). This distortion of scale could reflect some facts, especially the importance which the map's creator held a specific area of land, or the degree to which a piece of land had been explored or viewed as significant for navigation or trade.
In other words, the inaccuracies convey meaning and a type of knowledge. They are the kind of street-level knowledge Steven Johnson celebrates in The Ghost Map. Johnson sees today's mashups and online mapping applications as bringing something new to geographical knowledge. As he sees it, one of the key principles of this new generation of online maps is, "the importance of amateurs and unofficial 'local experts'" (Johnson, 225). However, looking at old, hand-drawn maps, one can find evidence of this same local expertise and local focus, if one cares to look for it. However, the mapping software is perhaps the best lens through which we can look to find this distortion.
