The Viking on watch would hold the three necklaces is his left hand and pump the pendulum with his right hand. The second marking necklace would be pulled thru his hand one knot at a time each time he pumped the pendulum. Each time the second marking necklace reached the top of the minute marker the Viking on watch would advance the minute marker necklace one minute marker.
Each time the minute marking necklace reached the top of the hour marker the Viking on watch would advance the hour marker necklace one hour marker.
The Viking would thus be able to see how far they were away from where they started by observing how much time there was between local noon and the Viking watch noon. This watch allows the Vikings a way to know where they are without being able to count or add. Keeping track down to the second would allow them to know where they were to within three miles all over the earth.
My hope is that archaeological evidence will support my Viking watch now that we have some idea what we are looking for... A stick of wood 14 inches long with a hole one inch from the end, and three necklaces with beads or knots. Two of the necklaces will have 60 beads and the other necklace will have 24 beads.