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Solid Brass Desktop Compass 5"
The beautiful and functional Hampton Nautical Three-Leg Brass Desk Compass is finely crafted of highly polished solid brass. It features an accurate arrow-slim needle with balancing crossbars, an adjustable 3-leg design for precise leveling, lift arm to secure the needle against excess movement and wear, and a sophisticated etched brass face. The Hampton Nautical Three-Leg Brass Desk Compass is a perfect gift for the nautical enthusiast or navigator.
- Solid Brass compass
- Precision Balanced 3-leg design
- Lift Arm secures needle against excess wear
- Etched Face with sophisticated designs
Understanding the basics of magnetism is key in understanding how this brass compass works. First it is important to look at a basic atom, with a nucleus of protons and neutrons, and a cloud of electrons rotating around it. The protons have a positive charge, neutrons have no charge, and the electrons have a negative charge. Though the charges of the protons and electrons cancel each other out, the electrons create their own magnetic fields. A rotating electrically charged particle creates a magnetic field, with magnetic poles, and so an electron has what is called an orbital magnetic dipole moment. Electrons, however, pair up around the nucleus so that each pair rotates in opposite directions, thereby cancelling this magnetic charge as well. By rubbing a needle across a piece of lodestone, however, the magnetic properties of the lodestone cause the rotating electrons to align their spins in the same direction. With all the electrons spinning in the same direction a flow from positive to negative is created, much like the flow of an electrical current, and the needle can now be used to construct this brass compass. Once the needle is magnetized its magnetic field exerts a torque on all other magnetic fields, and similarly responds to the torque exerted by the Earth’s magnetic field. Thus, when placed on the cork or string and allowed to move freely, torque causes the needle to align itself with the Earth’s magnetic field. The needle will now always point to one of the poles, and the basic brass compass is created. With such a needle-magnet placed over a brass compass rose, the face with the cardinal directions, it becomes possible to correctly determine any heading and safely navigate. As antique compasses worked purely on magnetism, they changed the history of sailing, allowing sailors to navigate on the open ocean, at night, and in poor weather, leading to the Age of Discovery. This antique compass for sale, though such a seemingly simple device, represents a feat of ingenuity and engineering, and a brilliant piece of history.