Compass anomalies:
Page 216: " To give the course of the drift [ longitude ] is a difficult
task in these latitudes, as there is a perceptible deviation of the compass
with every degree of longitude as one passes East or West."
In other words, Nansen's compass wouldn't tell him what the longitude was
even though he was on the opposite side of the Arctic basin from the
Magnetic North Pole! Why should the compass behave erratically from a point
so far away? This is because the magnetic lines of force enter all along the
inner rim of the doughnut-shaped opening; such that, as one passes along the
rim, the compass goes helter-skelter, Eastwards and Westwards, even though
one is on the far side of the opening from the Magnetic North Pole.
Due to polar anomalies in terms of compass ( longitude ) and curvature (
latitude ), Dr. Nansen and crew had been unable to precisely calculate their
position since the first moment that they had lodged their ship into the
ice. While trekking downwards from his point farthest North, he and Johansen
were still quite unsure of their position thanks to the currents and the
drift of the ice. They remained unsure for a long time as they headed South
on the Russian side of the Pole. As they got further down from the Pole,
however, the nature of their navigational difficulties took on a different
nature. They had let their watches run down and could not precisely
determine their longitude. Their difficulties in determining their longitude
at this point were not anomalous. ( As an example, by June 14th, Nansen
recorded his position to be 57* 40 of longitude but, later on, once he got
back to civilization, he felt that it had been more like 6* further East of
that. ) As he and Johansen headed South towards Franz Josef Land, Dr. Nansen
wasn't even sure on which side of the archipelago they would come down on!