There's something about antique maps that makes cartographers of us all. Many old maps are works of art. They are also history (occasionally incorporating deliberate or unintentional fantasy), cultural artifacts, and even public records with a very personal significance - as when discovering that one's high-rent urban residence was once charted as nothing more than a cow pasture on the outskirts of town. David Rumsey has been collecting maps for roughly two decades, and though your curiosity is unlikely to match his obsession, the David Rumsey Map Collection is an unparalleled resource for anyone with an interest in the subject.
Concentrating on 18th and 19th century depictions of the Americas, the online collection is notable for several reasons - the most obvious being its size. More than 8,800 maps are accessible through the website's database, and it will continue to grow as more of Rumsey's entire collection - numbered at 150,000 pieces - are added to the content. Size is also an impressive factor in another context, as the artifacts are scanned at a minimum 300 pixels per inch. This translates to exceptionally large files for a web resource, and allows photographic quality output on most printers - an important factor, as "personal use" printouts of the collection are permitted.
Next, there is the exceptional fit in this project, of a purpose and a medium that seem made for each other. Antique maps are artifacts of almost universal appeal, but are obviously limited in number and too physically delicate to be made available to the general public. Online, interested surfers from around the world can poke and prod to their heart's content, and in some cases, overlay information from different historical periods. (An option impossible with the original material.) And compared to three dimensional artifacts posted online for public access, two dimensional maps lose much less of their character when appearing on a computer screen.
All that said, the first attribute likely to strike new visitors will be the variety of ways in which the collection can be explored, from a simple browser interface to special Java-based software that needs to be downloaded first. Requirements, instructions, and caveats for all four methods are posted onsite, and we'll begin with the option recommended by the webmaster as the best introduction to the collection.
Clicking on a specific map -and moving from "Search" to "Data" in the index column- accesses detailed information about the chart, while double clicking will load the image into a pop-up workspace window. Here, visitors can zoom in on the selected map to such an impressive degree that they'd need to use a magnifying glass on the real thing.
A thumbnail image in the workspace window allows direct movement to specific areas on the selected map, and other workspace buttons access image data, browser Help, and - theoretically - a print option (though I kept encountering a "Printing is not supported" message during my visit). By using the workspace window to limit downloaded information to selected areas of the maps, Insight grants surprisingly quick access to highly detailed scans. This way, even users with slower connections can avail themselves of the full benefits of the online collection.
Similar in operation to the Insight browser, is the Collections Ticker - though it has a different method of delivery. In this case, thumbnail maps scroll automatically through a pop-up window which opens at the bottom of the computer screen, reminiscent of a stock ticker. Once you select a thumbnail, operation is identical to the Insight browser, with it's workspace window and related options. The Ticker is an interesting alternative for the casual surfer or fan of serendipity, but if you're looking for something specific as more than 8,800 images scroll by, you might want to start making provisions for your heirs.
For serious scholarship, the Insight Java Client (which requires a software installation to operate) offers such additional capabilities as exporting content to PowerPoint, click-and-dragging over a map to magnify a specific area, and the ability to open multiple collections at the same time. Finally, the GIS (Geographic Information System) browser allows overlays of historic maps with such current information as roads, government boundaries, and even satellite imagery. (Side by side comparisons are also available.) I can't personally vouch for this feature, since Mac users who haven't upgraded to OSX are shut out, but if your system and browser are compatible with Java 1.3, you should be good to go.
I did encounter a few glitches at the site, such as the occasional lack of a required scroll bar. (It's usually possible to force the browser to correctly redraw such an incomplete page, if you make it display a hidden component such as the window's Address Bar.) There is also the potential for complications when downloading full images. The Rumsey collection uses a phenomenal compression technology known on the site as the "MrSID" (though it's now called ExpressView), through which, for example, a compressed and downloaded 5 MB file can open into a 65 MB behemoth. (This is where remote users can really take advantage of those 300 ppi scan resolutions.)
Unfortunately, the creator of the software (LizardTech) no longer seems to be offering a standalone viewer (something they once offered, as I have one on my hard drive at the moment), nor a Macintosh compatible version of the plug-in (which is probably why I ran into printing problems at the site). We can only hope that this is a temporary limitation, and the available options will return to their earlier flexibility.
Even taking these handicaps into account, the collection is an amazing and frequently beautiful resource, while the basic Insight browser will be more than flexible enough for most visitor's needs. And regardless of what method we use to tour the site, we can be grateful that collectors like Rumsey are willing to share their treasures free of charge.
The David Rumsey Map Collection can be found at http://www.davidrumsey.com.