I've begun mapping sites that occur in Roughing It. Chapter 1 was simple, St. Louis and St. Joseph, Missouri. Chapter 2 has Sam, brother Orion and George Bemis on the Overland Stage heading west through Kansas. He reports stopping every ten miles or so. These Overland Stations and the Pony Express Stations I take to be the same. I have plotted ten such stations for Chapter 2. The final station being Cottonwood, where the Sphinx suggests they lay over for a few days. The National Park Service has a good on-line publication on the Pony Express and there are any number of other on-line references. But few of these provide an exact definition of station locations. My map can be seen at http://bscottholmes.com/twain/roughingit/chapter2 . If anyone can provide me with better coordinates I would be grateful.