Wow that is pretty amazing...
I wonder how to open those weird files.

Good stuff, thank you!  Keep us posted.   

Robert Koscik said:

Wow that is pretty amazing...
I wonder how to open those weird files.

Good stuff, thank you!  Keep us posted.   

The instructions are rather odd, but they do have a detailed instruction page on how to get the files.  Once you download them, they are what they call "geo referenced PDF files".  To get the georeferencing feature, you need to download a plugin for your PDF reader, but you can view the files without it just fine. 

I'll be interested to see what maps for Oregon they post later this year...

This is really exciting news for map geeks and history buffs! Eons ago, I worked in the map room at Oregon State University while in college, and as a land grant college, we carefully filed all of the generations of each topo in our USFS map cases -- that's where I first became aware of the early 20th Century topo maps.

In the age of digital imagery and the inter-webs, they've gradually made their way into the public domain, but it has been a long time coming to have the USGS systematically put this information out there.

Along the same lines, I'm hopeful that at some point the land management agencies are systematic about scanning and publishing their historic photo collections. There's so much at stake, since most are maintained only in the form of old prints, and thus one-of-a-kind images that can never be replaced if they aren't archived electronically.

Tom

Oh, and I would add that while it's unfortunate that they picked a Windows-specific plugin for their viewer, the actual files are PDF-compliant, so those of us using Linux or Mac OS can view them through any PDF viewer.

Tom