NavList:

Re messages by Apache Runner and Peter Fogg:-
That was indeed an interesting post and quote from Dictionarium Britannicum, 1736. The fact that other 'Dead' terms existed in says a lot.

I believe that Dead Reckoning was always the term used for a position not verified by either land or sky observations. The fact that here also is quoted that it includes set and drift in those days is also not a total surprise to me either, because;
1) In practice it is of no benefit for any seaman to plot his DR position without taking into account the effect of wind, current and tide. So I presume that when such information was known (which may not always have been the case of course) it was allowed for.
2) There would be no need for the navigator to differentiate between a DR position and an EP (estimated position) on the chart (simply because EP would not have been a common expression) - I believe this differentiation may have arose only in recent times for examinations etc. This is purely a guess I must admit, but I know for sure that (even though 35 years ago,we knew well the difference between an EP and a DR), we never used anything other than the letters 'DR' on the chart if we did not have an actual fix for any particular position plotted. (A fix was generally noted by a circle around the position plotted).

Of further interest to me is the use of AP (assumed position), regularly used here on NavList. This is a term that I don't recall encountering at sea or college. Is this a U.S. term or just a more modern term again? My reading of the term is that it is a position used in a hypothetical exercise - not in actual navigation. If I am wrong, then what is the difference between AP and EP?

Kinch
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