Compass and its practical application. How to use a compass correctly? Orienteering rules

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You can survive in the wilderness without a compass, but it’s very difficult. To avoid getting lost or lost, a topographic map and a reliable compass are not enough - you also need to know how to use them. Anyone can learn to navigate with a compass, and this article will help.

How to use a compass - compass marks

Each compass has its own look and design, but they are all designed on the same principle. Each compass has a magnetic needle pointing to the poles of the planet. Let's look at what parts a compass consists of:

A transparent plastic plate on which the compass is placed.
An arrow that indicates direction.
A transparent ring on which the compass (magnetic needle) is attached.
A rotating arc around a compass.
An arrow that rotates inside the compass.
A non-magnetized arrow that indicates direction.
Reference lines.

How to use a compass - how to hold it

The compass must be placed on the palm of your hand and brought to your chest. This is the correct position of the compass during any travel. If you just need to consult a map, place it on a flat surface and place a compass on top. This way you can navigate the terrain as accurately as possible.

How to use a compass - identifying directions

This is a quick and easy way to navigate the area. Look at the magnetic needle. Let's say you're going north.

Rotate the division scale. This is done until the magnetic needle overlaps the direction arrow. Both arrows should point north. After this, determine the direction of your movement. This can be done by looking at the direction of movement arrow.
Look where the graduation scale intersects with the direction of the movement arrow. Look at the graduation scale to determine your exact direction. If the intersection occurs near number 20, then you are moving 20 degrees northeast.

How to Use a Compass - Difference Between Magnetic/Geographic North Poles

Even taking into account the fact that they are both “Northern”, you will remember the difference very quickly, since it is very important for the correct use of the compass.

The difference in readings may not be significant, but a difference of 1 degree will mean a deviation from a certain target of 100 meters with every kilometer. What happens if you need to walk 10 or even 20 kilometers? It is simply necessary to take into account the difference.

How to use a compass - calculate your direction

When moving through open areas or forests, you need to periodically determine your direction. Rotate the compass so that the direction arrow matches your direction (where you are going). The magnetic needle will coincide only if you are moving north.

How to Use a Compass - Keep Moving

Hold the compass correctly. Turn with it so that the magnetic arrow on the division panel points to the north. Move in the direction the direction arrow points to. You can check the compass all the way, just be careful not to move the division panel.

How to use a compass - use landmarks

When you follow the direction indicated by the arrow, select a landmark (post, stone or tree). Do not select objects that are too distant (mountain) - they will not allow you to navigate with the necessary accuracy. Having reached one landmark, look at the compass and choose the next one.

How to use a compass - transfer the course to the map

Place the map on a horizontal surface and place the compass on top. The direction line should point north. Now position the compass so that it passes through your position and the arrow points north. Draw a line along the compass that passes through your position on the map. Stick to this direction.

In order to quickly and correctly navigate unfamiliar terrain, be able to choose the shortest path and know your location, you need to regularly practice with a compass and map, train your powers of observation and visual memory. A compass is a tourist’s most reliable companion, provided that they know how to use it. In order not to find yourself in an absurd situation when you have a compass, but you are lost and do not know where to go, study our article now, sitting with a cup of tea at your computer.

Modern technologies do not stand still. Scientists are developing gadgets that make human life much easier. Many modern developments have the disadvantage that they do not work offline.

To help travelers, navigators, walkie-talkies, transmitters and other devices for orientation in space have been developed. In most cases, due to the fact that they require constant electrical charging, it is not always possible to use them.

For this reason, the old method of orientation is used - the compass. It will help out no matter where you are, in the forest, desert, if you are a fan of hunting and fishing.

Its advantages:

Little weight.
Affordable price.
Small sizes.
Does not require additional power.

You can take navigators or other geolocation devices on a trip, but you should always take a compass, it will help you out everywhere. Many people don’t know how to use a compass, but it’s worth learning.

The instructions for use are quite simple, you just need to know the concepts from physics and geography. Before using a navigation device on the road, it is important to practice in familiar territory to understand how the arrows work. After this you can go traveling.

If you find yourself in the forest without a map or newfangled gadgets, a compass will help you find your way around the area.

Before using it, you need to remember particularly prominent large objects located on the ground. This is a lake, a building, memorable snags of trees.
Before you start your journey, put the compass in the working position, face the landmark and release the arrow from the brake, the arrow will point north.
Move 20–30 steps away from the selected landmark, draw an approximately imaginary line from the device to the landmark and remember the scale readings. In the future, this figure will be the main one to determine how far off course you have gone.
You need to measure the azimuth, this is the angle that lies between the direction north and the deviation from it to your landmark. So, in the future, you will be able to accurately determine the deviation from a given path back.
Moving forward, you should pay attention to the location of the arrow and align your journey according to their indications.
When finding the path, the device must not be tilted, otherwise it will show the wrong path and you will lose your way.

It is still better to use it with a map, since indicating with an arrow the magnetic poles of the earth, connecting them to the map, will allow you to determine the location and quickly understand where you are on the map.

If there is an anomalous zone nearby, that is, iron ore lies deep in the earth, the arrow will spin chaotically, you need to move away from this place and look at the readings again. You will quickly find your bearings after the arrow calms down and shows you the right path.

Device and characteristics

A compass is a round box, an arrow with two ends and a scale. The round box serves as protection for the arrow and the magnetic field that is created inside the box. The arrow has a red end that points to the south, a blue end that shows the location of the north.

Advice: When purchasing a navigation device, you should check its functionality, you need to bring an iron object to it, if the arrow deviates, then the compass is working. If you abruptly remove the iron object, the arrow should return to its previous position.

Types of compasses

View	Description
Electronic	The action is based on microprocessor calculation. The compass has a built-in GPS beacon. The coordinates are determined through the signal that the beacon sends to the satellite and back. The downside is the lack of a charging outlet.
Gyro-compass	Used to determine coordinates during sea voyages. It is mechanical, the action is based on the principle of a gyroscope, that is, the rotation of the earth around its axis. When the equator line is found, the arrow begins to rotate intensively. Very easy to use, always correctly determines the direction and is insensitive to changes in the magnetic field.
Magnetic	Principle: The earth's magnetic field interacts with the magnetic field of the compass, in which the needle will determine the location of the parts of the world. Very convenient to use, small-sized, cheap, but sensitive to magnetic anomalies.
Engineering	A type of magnetic one, only made in the form of a watch, from shock-resistant material, and has a strap that secures the compass to the hand. It is very convenient to use the engineering one. It is equipped with a rotating scale located on the glass, with which you can determine the azimuth, and a lens that magnifies small divisions of the scale.
Military	The most accurate device. What makes it different from other devices is its metal casing, which makes it reliable during combat operations.

In modern society, in the absence of a regular compass or those listed above, an experienced traveler will not go astray, since a compass can be built into the phone, very easily when the phone is newfangled. You can install an application on your iPhone that will show you the road like a navigator.

No matter what kind of compass you use, military, army, engineering, digital or tourist, this device will never let you down and will always help you navigate any terrain.

If you don't know how to use it, you can learn everything with the help of the Internet. On sites about compasses you can find information of interest about any compass. You can watch training videos in which experienced people will tell you in detail and show you how to use a compass.

Video

There are several types of compasses. To navigate in unfamiliar terrain (determine the cardinal directions), a simple compass, in which the direction indicator is a magnetized arrow, is enough. It is precisely these devices that prudent hunters, fishermen, mushroom pickers, and tourists take with them when going out into nature (going on a hike). At school they teach how to use a magnetic compass, but does everyone remember their geography lessons?

This article will help some to “refresh” their memory, and others will help them understand how to navigate unfamiliar terrain using a compass.

What you need to know about the compass

Its hand (after removing the lock) always takes a position in which one end “looks” to the North (marked on the dial as N or C), the other to the South (letters S or Yu), in accordance with the poles of the Earth. Since compasses are produced by different manufacturers, the designations of its sectors differ. How to understand that the device body is positioned correctly and not turned 180º? Otherwise, the true cardinal directions cannot be determined, and the meaning of orientation is lost.

The letters E or B stand for East, W or W for West.

When determining the position on the ground, it is customary to count from the direction “North”. Therefore, the end of the magnetic needle pointing to it is always marked. This is either a blue mark (sometimes green), or a dot made of phosphorescent composition. The tip can also be made in the shape of a triangle, directed at an acute angle to the magnetic pole.

But in any case, the side where the “marked” end of the arrow points is necessarily North. Consequently, you only need to turn the body of the device, adjusting the dial scale under it until it aligns with the printed designation N (or C). In older models of compasses, the “south” tip of the arrow is also marked (in red).

How to navigate with a compass

Few tourists, hunters or fishermen take a map with them - they mostly make do. Those who go outdoors with it know the operating procedure well. For most, it is enough to find the way back using a compass. Basically, it is purchased in order not to get lost. What should be done?

When setting off along the chosen route, you should determine the direction of travel. The lock from the arrow is removed, the compass is given a horizontal position and its body is rotated until the letter N of the dial aligns with the “north” tip. All that remains is to wait until the arrow “calms down”.

Having chosen a distant, clearly visible object (a tree, hill or other) along the route, you need to remember in which direction it is. That is, determine the azimuth. The graduation is also marked on the instrument scale. 00 is North, respectively, 90 is East, 180 is South and 270 is West. It is not difficult to calculate exactly what azimuth the movement will take.

If you have to change direction along the route, and this happens quite often, especially on rough terrain, then at each “turning” point you need to again determine a new azimuth, choosing some other object. You shouldn't rely on memory; all data must be recorded. Plus, it is advisable to count steps (with frequent changes of course) or time the movement (with long movements in one direction).

In order to return to the starting place, it is enough to move in the opposite direction. That is, orient the compass dial to the cardinal points, and mentally draw a line through the center of the device from the primary (measured before moving in the intended direction) azimuth value for a given point. If the movement on the ground was at an angle, for example, 300º, then you need to return in the direction of 120º. It is not difficult to understand if you consider that the difference between azimuths (“forward” and “reverse”) is always 180º.

In specialized stores that sell accessories for fishermen, hunters, tourists or athletes, you can find various modifications of magnetic compasses. In order to find your way in an unfamiliar place, the simplest, cheapest device is enough. It’s hardly worth spending money on a more “sophisticated” device, given that all its capabilities (functionality) will not be implemented in practice anyway.

Probably, in this regard, the only useful recommendation is to pay attention to “liquid” compass models. A special mixture is pumped inside their flask, which “quenches” the vibrations of the needle. Such modifications of the device are more convenient in that they allow you to navigate without stopping directly while moving. For a tourist traveling on foot, such a compass is preferable.

There are several ways to check the functionality of the device. The simplest of them is to bring the compass closer to any metal product (stained glass frame, door handle, etc.) right in the store. The arrow should not just deviate, but orient itself smoothly, without jerking. This sometimes happens with cheap models due to improper mounting on the axle.

Those who use a compass to “reference” a map to the terrain should remember such a calculation parameter as magnetic declination. The device shows the magnetic pole, but for all maps the geographic pole matters. In most cases, this error in orientation is not taken into account, but if maximum accuracy in determining coordinates is required, it will have to be taken into account. Relevant reference data is indicated on each sheet of the map.

To make sure that the direction to the North is chosen correctly, you need to take several “measurements” in different places along the way. The magnetic needle reacts to metals, and often the compass “lies” mercilessly, disorienting the user. For example, if there is any object nearby that affects its position (for example, a power line, a huge landfill invisible behind the planting, a “thread” of a buried pipeline, and so on). The same applies to swampy areas.

In this case, the effect of the so-called “swamp ores” appears. The reasons for “failures” in the operation of the needle can be very different, even “anecdotal”. For example, if during orientation you hold both the device and a metal object (knife or something else) in one hand. Experienced tourists are never limited to just determining the direction to the North, but constantly check the compass along the way.

When navigating, you shouldn’t rely only on a compass. Firstly, with a lack of experience, it is quite difficult to accurately determine the azimuth. Secondly, cheap instruments give significant measurement errors. To reduce the time spent finding the starting point, it is useful to remember natural landmarks - roads, plantings, large lonely trees, and the like.

In addition to the compass, it is advisable to purchase a device such as a pedometer. It will help determine the distances from one control point to another. Then you won’t have to track the time or calculate the number of steps. Consequently, the process of orientation on the ground will be significantly simplified.

Every searcher, fisherman or mushroom picker often has to go into unfamiliar places. And after some time, an urgent problem arises - how to get out of this place to the house and car. Of course, it is quite difficult to get lost near large cities, but even in an unfamiliar forest of 2x2 km you can get lost for a very long time.

Currently, many electronic assistants have appeared that can show the road using GPS navigation or simply by the position of cell towers. However, all these devices have one drawback - they require power. This means that it may happen that the GPS navigator’s batteries are dead or the cellular connection is not receiving.

Therefore, such a simple navigation device as compass. The compass does not require batteries to operate, and knowing how to use it correctly, you can not be afraid of getting lost even in the remote taiga.

Wherever navigation and location determination in space is necessary, one or another type of compass is used. But we will not go into details of their types. We are interested in the simplest tourist-type compass.

The simplest compass is an iron needle mounted on a vertical axis. This entire structure is located in a round housing. The iron needle represents a magnet. And since our Earth is also in some way a large magnet, then, due to some physical laws, an unusual phenomenon occurs - a magnetic needle suspended on an axis tends to turn towards the Earth’s magnetic pole. Fortunately for us, the magnetic pole practically coincides with the geographic pole. Thanks to this, we can assume that the compass needle always deviates in one direction - to the north.

Knowing the direction to the north, you can determine the other three directions - south, west and east. And once you orient yourself in these directions, you can easily move around in any area without fear of getting lost - just like sailors do.

But before I explain how to use a compass, I want to make a small digression. Before going to an unfamiliar place, be sure to study the map of the place in advance. A compass will be practically useless if you do not know the necessary landmarks or the approximate geography of the place.

Remember the approximate position and direction of all extended landmarks - roads, rivers, lakes, clearings, high-voltage power lines, etc. At the same time, outline the directions of entry and exit in advance if we are talking about a forest. Then you will know for sure that you shouldn’t leave the forest to the west, it lasts another 50 km, but in the north the forest is blocked by a river, and you can always go out there.

We continue to learn how to use a compass. First you need to choose which of these devices to purchase. There are mainly two types of compasses sold in stores – “tourist” and “orienteering”.

A tourist compass is that same simple “box” with an arrow and numbers in a circle.
An orienteering compass is a little more complex and is designed to be used for moving around a map. It usually has one or two flip-up sights for more precise determination of angles relative to landmarks, and often comes with a mirrored numeral scale.

For now we will consider only the first type of compass.

So, in addition to the arrow, the compass also has numbers in a circle, indicating the angle of rotation of the arrow from 0 to 360 degrees. Typically their graduation ranges from 5 to 15 degrees.

It is these numbers, together with an arrow, one end of which is usually clearly expressed in shape or color, that help to navigate the area. In this case, using knowledge of the direction to the north and deviation from this direction. This deviation, or the angle between the direction to the north and the direction to some landmark, is called AZIMUT in navigation.

In practice, especially in weather forecasts, we often hear the designations - south, northwest, east, and other cardinal directions. All these are also azimuths. Or multiples of 90 degrees (north, south, west, east), or 45 degrees - northwest, northeast, southwest, southeast. In geodesy and navigation there are other accepted designations for smaller angles, but they are not important to us for now.

What can we do to avoid getting lost using a compass and knowledge of azimuths? First, let’s define what azimuth is important to us? That is, the angle between what and north? You need to choose a landmark.

In relation to the forest, most often you need to know the direction of how to enter the forest and how to get out of it. It’s easier to enter the forest from the road; it will make a good landmark because of its great length.

So, we stand facing the road, take the compass in our hands and look at the azimuth, that is, the angle between the end of the arrow pointing north and the direction we are looking at the road. For ease of use, it is better to rotate the compass so that the end of the arrow coincides with the number 0 on the scale. In this case, the direction you look at the road will indicate some azimuth, for example, 315 degrees.
This is the azimuth of the direction of exit from the forest. And the opposite arrow (in this case - 135 degrees) is the reverse azimuth, that is, the direction of movement into the forest.

Now you can calmly walk through the forest, trying to adhere to a known return azimuth.
And on the way back, you need to do the same operation - turn the compass arrow to the north (0 degrees), and move in the direction of direct azimuth. Thus, you will come out onto the road with some offset relative to the place where you entered the forest.

To make it more clear, I’ll explain it “on the fingers”. If you enter the forest to the south, then you need to go back to the north. The same with forward and reverse azimuths. The main thing is to know
the direction to a predetermined landmark and where north is.

You will find out what else you can determine using a compass in the next article.

The lens compass (Figure 9-1) consists of three main parts: a cover, a base, and a rear sight.
a. Lid. The compass cover protects the floating dial. It contains an aiming line (front sight) and two luminous aiming dots used for night navigation.
b. The basis. The compass body contains the following moving parts:
(1) A floating dial mounted in the center so that it can rotate freely even when the compass is not held level (at an angle). The dial has luminous figures in the form of an arrow and the letters E and W. The arrow always points north, and the letters point east (E) 90° and west (W) 270°, respectively. There are two scales: the outer scale indicates millimeters, and the inner scale (usually red) indicates degrees.
(2) The frame of the floating dial is glass on which there is a pointer line (fixed).
(3) The frame ring is a ratchet that clicks when you move it. One circle contains 120 clicks; each click is 3°. A short luminous line, used in conjunction with the arrow, is located on the glass side of the frame's ring.
(4) A bracket attached to the base of the compass.
c. Rear sight (lens). The lens is used to read information from the dial. The aiming target is used in conjunction with the forward sight to detect objects. The rear sight also serves as a lock and clamps the dial to protect it when the compass is in the closed position. For the dial to float freely, the rear sight must be open more than 45°.

NOTE: When the compass cover is fully open, a scale ruler appears on the left side of the compass; in newer compasses the scale is 1:50,000.
WARNING: Some older compasses may have a scale of 1:25000. This scale can be used with 1:50000 scale maps, but all values must be divided by two. Check the scale!

In skillful hands, a compass can turn out to be not just a beautiful toy, but a rather powerful tool for navigating the terrain. According to Department of the Army Field Manual No. 3-25.26, when using the Army lens compass with sight and ruler, use several methods:

a. Using the central grip technique. First, open the compass so that the cover and base of the compass form a straight line. Move the lens (rear sight) to the rear position so that the dial floats freely. Next, place your fingers as shown in Figure 9-2. Spread your elbows out in different directions, and place a compass between your chin and your belt. To measure azimuth, simply turn your body towards the object, pointing the compass cap directly at that object. When you point at an object, look at the compass dial and read the azimuth value under the stationary black line indicator (Figure 9-2). This method has the following advantages over the aiming technique:
(1) It's fast and easy to use.
(2) This can be used in all visibility conditions.
(3) This can be used when navigating any type of terrain.
(4) This can be used without placing the rifle on the ground (however, the rifle must be slung over either shoulder).
(5) This can be used without removing glasses.

Figure 9-2. Central grip technique.

b. Using the compass-to-cheek technique. Move the compass cover, on which the aiming thread is located, to a vertical position; then move the rear sight forward a little. Look through the sighting slit of the rear sight, and align the thin line of the front sight with the selected object on the ground. Next, look at the dial through the peephole lens and set the azimuth value (Figure 9-3).
NOTE: The compass-to-cheek technique is used solely for aiming, and is considered the best technique for this.

Figure 9-3. Compass-to-cheek technique.

c. Pre-setting the compass to a specific azimuth. Different models of lens compasses differ slightly in detail, but their uses and principles are the same.
(1) During daylight or when there is a light source:
(a) Hold the compass in the palm of your hand.
(b) Rotate it until the desired azimuth falls under the black guide line (eg 320°), holding the azimuth as shown in Figure 9-4.

(c) Rotate the frame ring until the glowing line lines up with the north arrow. The compass is now pre-installed.
(d) To follow the azimuth, use the center grip technique and rotate your body until the north arrow lines up with the illuminated line. Next, go in the direction of the aiming thread (indicator line).
(2) During times of limited visibility, the azimuth can be set on the compass using the click method. Remember that one click of the frame ring is equal to 3°.
(a) Rotate the frame ring until the luminescent line aligns with the black index line.
(b) Find the desired azimuth and divide it by three. The result is the number of clicks you must make by rotating the frame ring.
(c) Calculate the desired number of clicks. If the desired azimuth is less than 180°, the number of cels with the rim ring should be made in a counterclockwise direction. For example, the desired azimuth is 51°¸ i.e. 17 clicks 3° counterclockwise. If the desired azimuth is greater than 180°, subtract that number of degrees from 360°, and divide by 3 to get the number of clicks. Turn clockwise. For example, the desired azimuth is 330°; 360° - 330° = 30 ¸ i.e. 10 clicks 3° clockwise.
(d) Apply the center grip technique with the compass preset as described above and rotate your body until the north-seeking arrow aligns with the luminescent line on the frame. After this, walk forward in the direction of the front cover's luminescent dots, which will align with the installed black index line holding the azimuth.
(e) When the compass is used in the dark, the reference bearing should be set while light is still available, if possible. With the original azimuth as the main one, any other azimuth that is multiplied by three can be set using the clicks of the bezel ring.
NOTE: Sometimes the desired azimuth value is not exactly divisible by three, then rounding up or down occurs. If the azimuth is rounded up, this results in an increase in the azimuth value and the object will be found further to the left. If the azimuth is rounded down, this will reduce the azimuth value and the object will be found further to the right.

d. Bypassing an obstacle. In order to bypass enemy positions or obstacles and remain oriented, you must make a detour around the obstacle while moving at right angles.
(1) For example, when moving to an azimuth of 90°, replace it with an azimuth of 180° and move 100 meters. Next, change your bearing to 90° and move 150 meters. Change your bearing to 360° and move 100 meters. When you change your azimuth to 90°, you will return to your original azimuth line (Figure 9-5).

Figure 9-5. Bypassing an obstacle.

(2) Avoiding an unexpected obstacle at night is a fairly simple matter. To make a 90° turn to the right, hold the compass using the center grip technique; Rotate to the center of the luminescent E underneath the luminescent line (do not move the frame ring). To make a 90° left turn, turn to the center of the luminescent W below the luminescent line. All this does not require changing the compass settings (frame ring), and also guarantees accurate 90° turns.

e. Bias. Intentional offset - a planned magnetic deviation to the left or right of the azimuth to the target. This is used when the target is located in front of or close to linear terrain features such as a road or river. Due to errors in the compass or map reading, a linear feature may be identified without knowing its location (right or left). Intentionally moving a certain number of degrees in a known direction compensates for possible errors and ensures that after reaching a linear feature of the relief, the user knows whether to go right or left in order to reach the object. Ten degrees is an adequate offset for most tactical applications. Each degree shift moves the course approximately 18 meters to the right or left for every 1,000 meters of movement. For example, in Figure 9-6, offset = 10 degrees. If the distance to point X is 1,000 meters, then point X is located approximately 180 meters to the right of the target.

Figure 9-6. Intentional drift towards a goal.

9-3. HANDLING THE COMPASS

Compasses are fragile instruments and require proper care!
a. Inspection. Before using the compass, a detailed inspection is required. One of the most important parts is checking the floating dial where the magnetic needle is located. The user must also ensure that the aiming thread is straight, the glass and crystal parts are not broken, and the numbers on the dial are legible. It is especially important that the dial rotates freely and does not snag.
b. Effects of metal and electricity. Metal objects and electrical sources may cause damage to the compass. However, non-magnetic metals and alloys do not affect the compass. The following approximate compass operating distances are suggested to ensure reliable compass performance:
High voltage electrical lines................................... 55 meters.
Field gun, truck, or tank.................................................... .. 18 meters.
Telegraph (telephone line) or barbed wire.................. 10 meters.
Machine................................................. ....................................... 2 meters.
Steel helmet or rifle...................................................... .......... 0.5 meters.
c. Accuracy. A compass in good condition is very accurate. However, the compass must be periodically checked in a known direction using a deviation from a known azimuth. Compasses with deviation greater than 3° should not be used.
d. Protection. When traveling with the compass deployed, make sure the rear sight is fully folded into the frame. This will lock the dial from floating and prevent vibration, as well as protect the crystal and rear sight from damage.

This material on using a compass was once herehttp://airsoft.lipetsk.ru/Articles/airsoft_compass_rus.htm

Bonus update 2016-04

What is Azimuth?

On the ground, you often have to move not in directions to the sides of the horizon, but in any other given directions. How to use a compass in such cases?

Suppose we are standing in the center of a circle divided into 360 parts and rotated so that its zero stroke points north. The remaining strokes will be directed from our point in different directions. Using the readings marked near the strokes, you can indicate the direction to any landmark. For example, we see that the factory pipe is located opposite the stroke with a report of 300. This means that the pipe is located away from us in the direction determined by the specified reading.

What does this countdown represent? Let us remember that our circle is divided into 360 parts. This means that each part is one degree. We oriented the circle with a zero stroke to the north. Therefore, the line passing through the center of the circle and the zero line correspond to the meridian.

Now it is not difficult to guess that our reading shows the angle in degrees, measured clockwise from the northern end of the meridian to the direction of the landmark. This angle is called azimuth. If the angle is measured from the true meridian, then the azimuth is called true. If the angle is measured from the magnetic meridian, then the azimuth is called magnetic.

Magnetic azimuths on the ground are determined using a compass on its circular scale. The scale is divided by strokes into 120 divisions. Each division between two strokes corresponds to three degrees (360: 120 = 3). Degrees are indicated by numbers in a clockwise direction every 5 scale divisions. This means that the signatures are given every 15° (0, 15, 30, 45, etc.).

Knowing what the division between two strokes is, it is easy to determine the reading at any point on the scale. For example, let's determine the countdown against the pointer at the front sight.
The smallest reading closest to the pointer, signed on the scale, is 330°. To this count we add the number of divisions in degrees from the stroke with this count to the pointer. There are two such divisions.

Knowing that each of them is equal to 3°, we get a reading of 336°. This reading will be the azimuth of the direction passing through the slot and the front sight.

To determine the azimuth of the direction to any landmark on the ground, we stand facing this object, release the brake of the magnetic needle and give the compass a horizontal position.

When the magnetic needle calms down, align the zero division of the scale with the northern end of the needle. In this position, the compass will be oriented, i.e. the zero line of the scale will indicate the direction to the north. Then, without disrupting the orientation of the compass, we turn its cover so that the slot is directed towards us, and the front sight is directed exactly towards the landmark.

The lid can be given this position by looking through the slot and the front sight at the observed object. In this case, you must always ensure that the northern end of the magnetic needle is aligned with the zero division of the scale. Counting against the pointer at the front sight will show the value of the magnetic azimuth to this landmark.

Using a compass, you can also solve the inverse problem, i.e., using a given magnetic azimuth, find the desired direction on the ground. Such problems have to be solved when moving along azimuths. To find the desired direction on the ground at a given azimuth, you should set the pointer at the front sight to a reading equal to this azimuth and release the brake of the magnetic needle.

Then set the compass in a horizontal position and orient it in the same way as when determining the azimuth to an object. Without losing the orientation of the compass, you need to look at the terrain through the slot and the front sight, and notice some landmark on this line. The direction from the standing point to this landmark will correspond to the specified azimuth.

Was here once too