A magnetic needle suspended in a vertical plane from the magnetic meridian makes an angle of the horizontal. If a magnetic needle is suspended such that it is free to rotate in a vertical plane and it is taken around the earth through the geographic poles, we find that at two places, the magnetic needle becomes normal to the earth's surface (i.e., the needle becomes vertical) and at two places it becomes parallel to the eath's surface. For more details download the AutoCAD drawing file from our Cadbull website.
