where you are in the world or where you want to go has always been
important to the traveller, land owner and surveyor. The early explorers
and navigators took advantage of the earth's magnetic field by using the
compass to determine direction. The stars, sun and moon were also used to determine both direction
and location. A simple example of determining direction is to accept the fact
that the sun rises in the east and sets in the west. This means that if you look towards the sun at noon, you will be
of the early property grants and communities in Nova Scotia were
positioned by the use of the compass but astronomic observations using
Polaris (the north star) or the sun to obtain direction were also common
for surveyors. Just think of communities that have a North, South, East or West
Street. These streets were either positioned to run in the directions in
which the streets were named or, in the case of North Street and South
Street in Halifax, they marked the most northerly and southerly limits of
the community in the early days of settlement.
latest technology also has us looking towards the heavens but using man
made satellites. The arrangement of satellites that we use to obtain position and
direction is known as a "global positioning system", or better
known by the initials GPS. For a few hundred dollars anyone can buy a small hand held receiver
that will generally provide better than 30 meter accuracy. The survey
community uses GPS but requires results to centimetre accuracy for various
projects. The equipment required to obtain this high level of accuracy
generally increases in price as the speed and precision of results
increases. Costs can approach $100,000 for equipment that will provide
accuracy results within seconds.
is now being used for all facets of the military, transportation industry,
recreational boating, forestry, camping and the uses are increasing, it
The next step is that cell phones will also act as GPS receivers. You will always know where you are if you have your phone on. The potential down side of this development is that the phone
company will also know where you and your phone are. So much for privacy.
however, are very excited about GPS since it can provide reliable results,
all weather operation, 24 hour availability, direction between non-visible
points on the ground, increased speed of location and total computer
compatibility. The surveyor can now locate that old wooden post a mile back in the
woods and relate it to the one at the side of the road. A line can then be marked on the ground from the road directly to
the old post.
can learn more about GPS by searching the Internet. The results, however, will likely number several
million ... more than enough information for anyone to become an expert.