NavList:

While finishing my 10,000 steps last night I watched a superb cloud-free sunset over high ground 40-50 miles distant, and I was impressed by how easy it was to spot the precise moment the last bit of Sun disappeared below the horizon.  I began to wonder if with a water horizon, especially over the next couple of weeks when the Sun will be setting in the west, if it might be possible to calculate your longitude without a sextant and how accurate it might be.  You’d need an accurate timepiece, probably a good idea of your latitude, and either navigation tables or moonset graphs.  Suggestions please. DaveP