What is the Point of a Compass?
A magnetic compass uses the natural magnetism of the Globe upon which we all stand. Planet Earth has a magnetic field – North is north, and South is south. The pointer on a magnetic compass will always point Northward, once we know where North is, a fixed reference point, and we know that a circle has 360 degrees it is possible to know in which direction the boat is sailing or which way to sail to get to where we want to go. If we want to sail to the South, we know that South lies directly opposite to the needle pointing North i.e. 180 degrees etc. A bearing could be anyone of those 360 degrees, remember the needle will always point to the North. Even a walker’s hand-held compass is better than nothing, always take a compass with you when at sea – or on land if in remote places that are unknown to you.
The point is that boaters can become disorientated because of being out of sight of land because one falls asleep, is ill, there is an emergency, one could sail into another country’s territorial waters, because it is dark, or the weather turns inclement and you get blown away from the coastline etc. At night time some navigators can navigate by looking at the stars, astral navigation, however many none professional sailors do not have this level of skill. Plus, there are occasions when catastrophic breakdown in electronic systems on larger boats means that one has to go back to basics, it always pays to understand the basic skills.
Basics in sailing terms means knowing how to use a magnetic compass, how to take a bearing and follow a course in relation the where you want to go using a compass, having knowledge of weather and barometers and barometric pressures and what they are telling you, watching for tell tale signs of changes in wind and or sea state etc.
A binnacle is a waist high pedestal or casing made to contain a compass on board a ship or large sailing vessel. It is possible to purchase a sea-going compass encased in wood, the needle may be suspended in alcohol, and they are robust being designed for nautical use. For serious sailors a purpose-built compass is a must, for keen amateurs – who may venture long distances it is a strong recommendation. If you know where you are going you will know easily how to return and that makes life much safer. NB: Always look out for metal/iron objects or overhead cables when using a compass as it will affect the readings.
Author: R. Langley