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A plain compass has no adjustment and always reads magnetic
north.
A vernier compass has an adjustable scale that allows for the
"setting off" of the magnetic declination and the compass can then
directly read true north.
There exists also the__________, that is a compass with a very
special purpose of easily determining "Latitude" and "True North".
The solar compass was invented in 1835 by William Austin Burt of
Michigan after he had discovered the iron deposits located in the state
and concluded that a regular compass would give such erroneous
readings as to be almost useless. By making _________ on the sun or
other stars, the latitude of the location can first be determined and then
"True North" can be determined. The solar compass also has the
ability to measure horizontal angles much like a transit.
Figure 9.4.1. A solar compass
________ is the next type of a compass, used with a chain when
traversing, this instrument provided a relatively quick method of
measuring horizontal directions in surveying, but not with the
accuracy of a theodolite.
The magnetic compass is an old Chinese invention, probably first
made in China during the Qin dynasty (221-206 B.C.). Chinese
fortune tellers used loаdestones (a mineral composed of an iron oxide
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