Place-n-Time comes with a handful of sample map data files from the United States Geological Survey (USGS). Those files allow you to get going. The odds are great, however, that you are more interested in parts of the country beyond those sample files.
Place-n-Time uses sets of data files containing digital line graphs (DLG's) that are provided by the USGS in the Spatial Data Transfer Standard (SDTS) format. There are three series of DLG's: small scale, intermediate scale, and large scale. Perhaps you already have a collection of these DLG's and know how to get more. If not, read on.
The USGS lists the files available for download for each series. They are listed alphabetically by name:
The large scale DLG's are also listed by state
When you click on the map name, you will be presented with a list of subdirectories. The DLG's currently supported by Dapper Mapper will be found in the boundaries/, hydrography/, and transportation/ directories. For small scale maps, all supported themes are located in the same directory and contain .bound., .hydro., or .trans. in their names. Note that the files you want will have names ending in sdts.tar.gz. Other formats (such as opt.gz) are not supported.
What if you don't know the name of the map?
Well, for small scale maps, the map name matches the name of the state.
For large scale maps you may browse the appropriate by state list and hope to see a familiar name. A better idea is to select GNIS from Place-n-Time's View menu, search for and select your area of interest, then click the Details button. The name of the large scale map will be shown in the Cell (quadrangle) field.
For intermediate scale maps, finding a name is less easy. Sadly, the USGS removed the simple, quick, graphical index maps from their site a few years ago. With a bit of patience, you can use their Earth Explorer. In step "1. Select your datasets(s)", click on the "+" next to the "Digital Line Graphs" category, then check the check-box for "DLG 1:100k". Continue with steps 2 and 3. When the Results Summary page appears, click on "DLG 1:100k" in the Data Set column of the table. When the Results page appears the map name will be shown in the table. Note that there is an intermediate scale DLG for each half of the map. To determine which half you want, go to the "Show footprint" column and click "Show". This displays the footprint of the original paper map, not the DLG. Decide which half, west or east, of the footprint you are interested in. The DLG's name will have a "w" or an "e" appended to the map name. You may then download the DLG's from Earth Explorer, or go to the lists mentioned above. If you have good luck with Earth Explorer, it may also be used to find large scale DLG's.
Here is an example of finding and loading a large scale DLG:
(This example assumes that your browser downloads files to ~/Desktop/, that your SDTS files still live where the sample files were installed, and that you have write access to those directories. If this is an incorrect assumption, please make appropriate adjustments in steps 10, 11, and/or 17.)
If desired, you may click your browser's Back button and repeat steps 15 thru 17 (modifying the names appropriately) for the other supported themes, followed by step 18 to view the new data.
When you are looking for other files and need another GNIS file in step 5, you can find it at http://www.dappermapper.com/data/usgs/gnis/.
Notice that in steps 2 and 3 in the example you changed the way that Place-n-Time searches for the SDTS files. Normally Place-n-Time looks in the appropriate lookup file to see where to find the appropriate SDTS files. By choosing Search all SDTS files you allow Place-n-Time to go hunting for files that are not in the lookup files, such as the new files that you just loaded. This works fine if you only have a small number of files, but if you have many files you will want to speed things up by listing them all in the lookup files. To see how to do that read the "Creating Lookup Files" appendix in the Place-n-Time user's guide.
Also, be aware that Place-n-Time defaults to using lookup files when
you start it. So if you restart Place-n-Time it won't find your new
files unless you have added them to the lookup files or set
Searching to Search all SDTS files again.
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Dapper Mapper