Gun throws mooring by SGDG
Large and old solid walnut writing box C1870
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A compass is an instrument used for navigation and orientation that shows direction relative to the geographic "cardinal directions", or "points". Usually, a diagram called a compass rose shows the directions north, south, east, and west on the compass face as abbreviated initials. When the compass is used, the rose can be aligned with the corresponding geographic directions, so, for example, the "N" mark on the rose really points to the north. Frequently, in addition to the rose or sometimes instead of it, angle markings in degrees are shown on the compass. North corresponds to zero degrees, and the angles increase clockwise, so east is 90 degrees, south is 180, and west is 270.
The first compasses in ancient Han dynasty China were made of lodestone, a naturally magnetized ore of iron. The compass was later used for navigation during the Song Dynasty of the 11th century. Later compasses were made of iron needles, magnetized by striking them with a lodestone. Dry compasses began to appear around 1300 in Medieval Europe and the Islamic world. This was supplanted in the early 20th century by the liquid-filled magnetic compass.
A sextant is a doubly reflecting navigation instrument that measures the angle between two visible objects. The primary use of a sextant is to measure the angle between an astronomical object and the horizon for the purposes of celestial navigation.
The octant, also called reflecting quadrant, is a measuring instrument used primarily in navigation. It is a type of reflecting instrument.
The inventors of the octantTwo men independently developed the octant around 1730: John Hadley (1682–1744), an English mathematician, and Thomas Godfrey (1704–1749), a glazier in Philadelphia. While both have a legitimate and equal claim to the invention, Hadley generally gets the greater share of the credit. This reflects the central role that London and the Royal Society played in the history of scientific instruments in the eighteenth century.
The ships log is the instrument used to measure the speed of a ship. The speed of a ship was formerly estimated using a boat log. The plank was tied to a rope with regularly spaced knots that a sailor counted aloud as they slid between his fingers. The count was made during the time of an hourglass. The resulting number, expressed in knots, therefore measures a speed and not a length. As a result of the Anglo-Saxon measurements, the nodes were spaced at 47 feet and 3 inches (14.4 m) and the hourglass was calibrated to measure a period of 28 seconds.
Campaign drawing Instruments of navigating officers were small boxes furnished with instruments for navigation with various rules and instruments.
The reflecting circle was invented by the German geometer and astronomer Tobias Mayer in 1752, with details published in 1767. His development preceded the sextant and was motivated by the need to create a superior surveying instrument.
Jean-Charles de Borda further developed the reflecting circle. He modified the position of the telescopic sight in such a way that the mirror could be used to receive an image from either side relative to the telescope. This eliminated the need to ascertain that the mirrors were precisely parallel when reading zero. This simplified the use of the instrument. Further refinements were performed with the help of Etienne Lenoir. The two of them refined the instrument to its definitive form in 1777. This instrument was so distinctive it was given the name Borda circle.
A theodolite is a precision instrument for measuring angles in the horizontal and vertical planes. Theodolites are used mainly for surveying applications, and have been adapted for specialized purposes such as meteorology and rocket launch.
The barograph or barometer: The oldest recording barometer system was invented by the Englishman Moreland in 1670 but it is the capsule of Vidie which is the "engine" of most current devices. To obtain greater displacement and stresses, a stack of capsules, usually five, is used. Barometers are also called barographs. Many are presented as "luxury" items in a glazed box with mahogany or other precious wood studs but there are also much more rustic designs.
The barometer is a measuring instrument used in physics and meteorology to measure atmospheric pressure. Secondarily, it can be used as an altimeter to approximate altitude.
The Anemometer: It is therefore a device for measuring the speed or the pressure of the wind. There are several variants
The first anemometer was invented by Leone Battista Alberti in the 15th century1. He used a plate anemometer where the wind strength was estimated using the angle from the vertical that a moving plate, rotating about a horizontal axis, adopted at equilibrium between the force of the wind And that of gravity.
The ship's telegraph, also known as Chadburn by association on behalf of the world's largest manufacturer or telegraph, is a mechanical device (originally) that transmits propulsion orders from the bridge to the Machines.
The engine room telegraph is the repeater.
Engine room telegraph: an engine order telegraph, is a communications device used on a ship for the pilot on the wheelhouse to order engineers in the engine room to power the vessel at a certain desired speed.