Screw-cutting latheA screw-cutting lathe is a machine (specifically, a lathe) capable of cutting very accurate screw threads via single-point screw-cutting, which is the process of guiding the linear motion of the tool bit in a precisely known ratio to the rotating motion of the workpiece. This is accomplished by gearing the leadscrew (which drives the tool bit's movement) to the spindle with a certain gear ratio for each thread pitch.
Vernier scaleA vernier scale ( ), named after Pierre Vernier, is a visual aid to take an accurate measurement reading between two graduation markings on a linear scale by using mechanical interpolation, which increases resolution and reduces measurement uncertainty by using vernier acuity.
TheodoliteA theodolite () is a precision optical instrument for measuring angles between designated visible points in the horizontal and vertical planes. The traditional use has been for land surveying, but it is also used extensively for building and infrastructureconstruction, and some specialized applications such as meteorology and rocket launching. It consists of a movable telescope mounted so it can rotate around horizontal and vertical axes and provide angular readouts.
Setting circlesSetting circles are used on telescopes equipped with an equatorial mount to find celestial objects by their equatorial coordinates, often used in star charts and ephemerides.
AlidadeAn alidade () (archaic forms include alhidade, alhidad, alidad) or a turning board is a device that allows one to sight a distant object and use the line of sight to perform a task. This task can be, for example, to triangulate a scale map on site using a plane table drawing of intersecting lines in the direction of the object from two or more points or to measure the angle and horizontal distance to the object from some reference point's polar measurement.
RulerA ruler is an instrument used to make length measurements, whereby a length is read from a series of markings called "rules" along an edge of the device. Alternatively, it is called a rule, scale, line gauge, or metre/meter stick. Usually, the instrument is rigid and the edge itself is a straightedge ("ruled straightedge"), which additionally allows one to draw straighter lines. Rulers are an important tool in geometry, geography and mathematics.
AstrolabeAn astrolabe (Ancient Greek: , romanized: astrolábos, lit.'star-taker'; Arabic: ٱلأَسْطُرلاب, romanized: al-Asṭurlāb; Persian: ستارهیاب, romanized: Setāreyāb) is an astronomical instrument dating to ancient times. It serves as a star chart and physical model of the visible half-dome of the sky.
GearTwo intermeshing spur gears rotating at different velocity due to differing gear ratioA gear or gearwheel, also called a toothed wheel, or cog is a rotatingmachine part typically used to transmit rotational motion or torque by means of a series of "teeth" that engage with compatible teeth of another gear or other part. The teeth can be integral saliences or cavities machined on the part, or separate pegs inserted into it.
SextantA sextant is a doubly reflecting navigation instrument that measures the angular distance between two visible objects. Its primary use is to measure the angle between an astronomical object and the horizon in celestial navigation. Estimating this angle, the altitude, is known as sighting or shooting the object, or taking a sight.
Tycho BraheTycho Brahe ( TY-koh BRAH-(h)ee, - BRAH(-hə); Danish: [ˈtsʰykʰo ˈpʁɑːə] ; born Tyge Ottesen Brahe, Danish: [ˈtsʰyːjə ˈʌtəsn̩ ˈpʁɑːə]; 14 December 1546 – 24 October 1601), generally called Tycho for short, was a Danish astronomer known for his comprehensive and unprecedentedly accurate astronomical observations which helped to turn astronomy into the first modern science and launch the Scientific Revolution.Graduation (scale)A graduation is a marking used to indicate points on a visual scale, which can be present on a container, a measuring device, or the axes of a line plot, usually one of many along a line or curve, each in the form of short line segments perpendicular to the line or curve. Often, some of these line segments are longer and marked with a numeral, such as every fifth or tenth graduation.
GoniometerA goniometer is an instrument that either measures an angle or allows an object to be rotated to a precise angular position. The term goniometry derives from two Greek words, 'angle' and 'measure'. The protractor is a commonly used type in the fields of mechanics, engineering, and geometry. The first known description of a goniometer, based on the astrolabe, was by Gemma Frisius in 1538.*As an Amazon Associate I earn from qualifying purchases.