NavList:

Intriguing. 

All my navigation in the mountains has been by map and hand bearing compass.  The idea of using a sextant never once occurred to me.  Though as I reflect on this, I did all my serious hiking as a younger man and all my sailing as an older one.  So my mountain experiences didn't overlap much with my knowledge of sextants.

Your comment does bring to my mind David Thompson, who performed the initial mapping of much of western Canada using a sextant and artificial horizon.  http://www.northwestjournal.ca/dtnav.html contains the account of a fellow who studied Thompson's journals pretty carefully in this respect.

Lewis and Clark attempted the same thing, but let their chronometer run down early on in their trip, and seemed to never fully understand how celestial navigation actually worked.  They kept resetting their chronometer to local solar noon, thinking they were doing everything that was required.

When they got back to Washington, their journals documented a bunch of valid latitudes, but no longitudes at all.

Bob