NavList:

For a given course and distance you enter a Traverse Table and get the corresponding values of difference in latitude and departure. Say you have eight pairs of dlat dep values you just add the dlat values together, taking care of whether it is north or south. Likewise with dep values, taking care if east or west. Then you have the resulting offset from your start position. Departure values can be transformed into dlong values, either with a special table or with the travere table itself.

Roswall, in his Navigation, Stockholm 1824, says that "the Englishmen often use the Gunter scale" and that the French use "Quartier de reduction", a graphical devise for traverse calculations. He concludes that "However, now that tables are used nearly everywhere we don't get into details of these graphical operations".

Lars