They also have a sighting wire that can be lined up with the sighting groove on the magnifying lens to sight far away landmarks.
This feature is especially useful for long distance navigation, as you can pinpoint landmarks for setting your travel direction with a higher degree of precision than with the single marking on a baseplate compass.
Lensatic compasses are also several ounces heavier than baseplate compasses, which will contribute to the dry weight of your pack. Lensatic compasses, often made with the military in mind, are considerably more weatherproof and durable than baseplate compasses.
This makes gyrocompasses more accurate, mostly because other magnetic influences in the environment do not affect their readings. Gyrocompasses are large and heavy, often measuring more than a foot tall and weighing more than 50 pounds. They also require electrical power to spin the disc used for their readings.
Keep the following features and considerations in mind to see which magnetic compass fulfills your specific navigational needs. The magnetized needle is the most important component of a magnetic compass. Most magnetized needles are suspended in fluid and pivot on a low-friction bearing to allow the magnetized needle to easily point to magnetic north.
Compasses with global needles are usually more expensive, but the extra cost might be worth it if you plan on using your compass around the world. Along with south and north magnetic poles, the Earth also has multiple layers of magnetized metal underneath its surface.
To compensate for this difference, many compasses will allow you to adjust your declination, which is the variance in degrees between true and magnetic north.
The map you use with your compass should list the magnetic declination of the area you will be navigating. Not all local maps will list the magnetic declination, but topographic maps of your state are available from the United States Geological Survey USGS that list the declination.
The method for making the declination adjustment will differ among compasses, but most require a small screwdriver or other tool for refined adjustments. Some compasses offer the convenience of toolless adjustment that can be turned with your fingers instead of a screwdriver, but at the cost of less refined adjustment capabilities.
The bezel guides you toward a desired destination by allowing you to set the bezel marker in the exact direction you want to go in relation to magnetic north. For example, if you want to head 52 degrees southeast, or head in the direction of a landmark you picked out with your binoculars , you set the bezel marking to that direction.
You are now part of a group of navigators that goes back hundreds of years. Research dates the use of the magnetized mineral lodestone as a compass all the way back to the year 1, Ancient Chinese explorers learned that they could float the stone on a small piece of wood in a cup of water and the stone would always point to the north pole. Sailors later discovered that rubbing a needle against a piece of lodestone made the needle magnetic and the evolution of the modern compass began, along with superstitions.
Prior to the scientific explanation, sailors thought the compass was a magical object that could tell fortunes and cure illness. They also thought that onions and garlic could block the magnetic force, so those ingredients never boarded their ships.
Luckily, we know that compasses today are useful tools that help us find our bearings — no magic required. Congratulations on joining the club of compass navigators!
The ancient Chinese are believed to have created the first compass. This version was used on a ship around It can also be used to lock the compass with the cover and keep it secured. Cover: The cover holds the sighting wire as well as the luminous sighting dots necessary when navigating at night. It also protects the floating dial and the crystal when closed. Base: On the other hand, the base contains the floating dial, the crystal that protects the dial, the bezel ring, and the thumb loop.
Thumb loop: It is the thumb loop that serves as a lock that secures the compass when closed. Sighting Wire: It is used for sighting when determining direction or exact azimuth. Compass Dial: The compass or floating dial has two scales: outer scale for mils black and inner scale for degrees red. It is mounted to float freely. Bezel Ring: It secures the glass crystal.
In total, it contains clicks, where each equates to three degrees of declination. Black Index Line: It is a fixed line on the glass used as reference for the direction. Check the glass crystal. Make sure there are no cracks or damages. Check the compass dial. It must be floating freely, which means it should not be sticking, and the numbers are readable.
Inspect the cover. The sighting wire should be straight. Check the lens. The lens cover should be straight and flat on the crystal glass, and when closed, the sighting wire should be crossing the middle of the sight slot. Inspect the black index line. Navigation has taken on many forms over the years. Here at Brunton, we manufacture a variety of different compasses for varying needs in the field.
A lensatic compass is just one of the many navigational tools we have built. A lensatic compass is often referred to as a military compass, and is typically used by the U.
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