Global Positioning System Reference
In-Depth Information
FIGURE A2.
The difference between a rhumb line on an unprojected map (a) and on a
Mercator map (b), assuming that the course direction is 45
\
north.
map (to account for converging meridians), but on the Mercator map, the line
is straight.
The Gyrocompass
A gyrocompass is shown conceptually in figure A3. The axis,
CD
, of a spinning disk
is permitted to move freely, but another axis,
AB
, is constrained to remain in the
