FINDING NORTH;- If you want to get from a point at the bottom of a map to one at the top, you need to head true north. True north is a geographical direction represented on maps and globes by lines of longitude. Each line of longitude begins and ends at the Earth's poles and represents direct north and south travel. DIFFERENCES BETWEEN THE THREE NORTHS; TRUE NORTH;- Each day the Earth rotates about its axis once. The ends of the axes are the True North and South poles. True North on a map is the direction of a line of longitude which converges on the North Pole. GRID NORTH;- The grid lines on Ordnance Survey maps divide the UK into one kilometre squares, east of an imaginary zero point in the Atlantic Ocean, west of Cornwall. The grid lines point to a Grid North, varying slightly from True North. This variation is smallest along the central meridian (vertical line) of the map, and greatest at the map edges. The difference between grid north and true north is very small and for most navigation purposes can almost always be ignored. MAGNETIC NORTH;- A compass needle points to the magnetic north pole. The magnetic north pole is currently located in the Baffin Island region of Canada, and from the UK, is west of true north. The horizontal angular difference between True North and Magnetic North is called MAGNETIC VARIATION or DECLINATION.The approximate difference between True North and Grid North is between 0 and 5 degrees. THE DIFFERENCES ;- The horizontal angular difference between True North and Magnetic North is called MAGNETIC VARIATION or DECLINATION. The horizontal angular difference between Grid North and Magnetic North is called GRID MAGNETIC ANGLE. It is this angle which needs to be applied when converting between magnetic and grid bearings. FINDING NORTHS BY COMPASS;- 04 FACTS;- 1-Compasses, on the other hand, direct you to magnetic north, a point in the arctic regions of Canada that continually shifts location based on the activity of the Earth's magnetic fields. 2-A compass needle is magnetized and freely suspended to allow that horizontal force to pull it toward magnetic north as well. 3-But the Earth's magnet isn't perfectly aligned with the geographical poles. For that reason, there is a difference between true north on a map and the north indicated by our compass. That difference is called the magnetic declination and is measured by the angle between true north and magnetic north when plotted on a map. 4-Magnetic declinations vary from place to place, depending on the intensity of the Earth's magnetic fields. For instance, if you hold out a compass in New Zealand, magnetic north will be about 20 degrees east of true north, whereas the declination in Los Angeles is 12 degrees. Geographical lines do exist where true north and magnetic north are aligned, and these are called agonic lines. 4- HOW STUFF WORKS;- 06 FACTS;- 1-One of the simplest ways to find true north is with a Global Positioning System (GPS). A GPS recognizes your location by compiling the location information provided by multiple satellites that orbit the Earth. If you have one, you can select a 'true north' setting on your GPS, enter your destination, and it takes care of the rest. 2-Some cell phones are also equipped with compass capabilities.There are also free compass programs that you can download from the Internet to your phone. The compass will come into action when you point the phone in the direction of the sun. 3-To find true north, you need to know your local declination value, or the angle difference between true north and magnetic north, discussed earlier. That information will either be listed in your map's legend or you can find it online at government Web sites, such as the National Geophysical Data Center. 4-Why go to all this trouble? Even a 1 degree difference in true north and magnetic north can land you up to 920 feet (280 meters) off-course. There are a few options for adjusting your compass to true north. First, be sure to know whether the declination number is positive or negative, which is determined by whether you are east or west of the agonic line. If you are east of the line, it will be negative, meaning you turn the ring clockwise; west of it is positive, meaning you turn the ring counterclockwise. 5-Some compasses allow you to manually adjust the needle to compensate for the declination. Otherwise, you can use the bezel ring on a compass to set the magnetic declination by turning the ring until the orienting arrow points to your declination value. Then, hold the compass in your hand.

6-TO FIND THE NORTH OF YOUR HOUSE,SELECT THE CENTRE OF THE HOUSE & STAND FACING MAIN GATE .When the needle and orienting arrow line up, the direction of travel arrow on the base will point true north.You can also accomplish this by aligning the orienting arrow and the direction of travel arrow.Then, hold out your compass and turn your body until the needle points to your declination. The orienting arrow and direction of travel arrow indicate true north.

7-Check it through all the directions & outside the gate also.If the difference is 5 to 7 degree;then take the middle of it.For example,if true north is -32 or +32 to -37 or +37 degrees from your main gate ,then point out 35 degree

as 0 degree north. FINDING TRUE NORTH WITH THE SUN; 04 FACTS;- 1-We'll explore ways to find true north using our celestial compass, the sun. If you're lost during the day somewhere without a map, compass or GPS handy, the best method to find your direction is to look up. The movement of the sun can illuminate your way true north. But to use this solar guide, you'll need to remember a few important things. 2- In the Northern Hemisphere, the sun always rises in the east and sets in the west. At noon, it looms in the middle of the horizon and directly south. That means when you're facing the sun at noon, walking directly toward it will take you south. 3-Walking with the sun at your back means you're heading north. The opposite is true in the Southern Hemisphere.If it isn't noon, and you want to find your directions during daylight, an analogue watch( a watch whose display is not digital but rather analog with a traditional clock face) with minute and hour hands can serve as a substitute compass. 4-First, make sure the watch displays the correct time. Then, point the hour hand at the sun. Next, holding the watch in place, imagine an angle formed by the hour hand and a line from the 12 o'clock position to the center of the watch. Then draw an imaginary line bisecting that angle. That line indicates south in the Northern Hemisphere. During daylight saving time, create the angle from the one o'clock position instead of the 12 o'clock position. HOW COMPASSES WORK;- 03 FACTS;- 1-No matter where you stand on Earth, you can hold a compass in your hand and it will point toward the North Pole. What an unbelievably neat and amazing thing! Imagine that you are in the middle of the ocean, and you are looking all around you in every direction and all you can see is water, and it is overcast so you cannot see the sun... How in the world would you know which way to go unless you had a compass to tell you which way is "up"? Long before GPS satellites and other high-tech navigational aids, the compass gave humans an easy and inexpensive way to orient themselves. 2-But what makes a compass work the way it does? And why is it useful for detecting small magnetic fields The reason why a compass works is more interesting. It turns out that you can think of the Earth as having a gigantic bar magnet buried inside. In order for the north end of the compass to point toward the North Pole, you have to assume that the buried bar magnet has its south end at the North Pole. If you think of the world this way, then you can see that the normal "opposites attract" rule of magnets would cause the north end of the compass needle to point toward the south end of the buried bar magnet. So the compass points toward the North Pole. 3-To be completely accurate, the bar magnet does not run exactly along the Earth's rotational axis. It is skewed( inaccurate) slightly off center. This skew is called the declination, and most good maps indicate what the declination is in different areas (since it changes a little depending on where you are on the planet). .....SHIVOHAM....