A watch that will give an audible sound at a pre-set time.
A term used to denote a watch with hands rather than a digital display.
Automatic working figures moving in conjunction with the movement mechanism. Striking Jacquemarts or jacks, which are figures (often humans provided with hammers) striking bells to supply the sound for the hour and quarter hours. The hammers take the place of the bells clapper.
An extra dial for information.
Also called the hairspring; the spring governing the balance.
A device which, by oscillating, regulates the movement of the train of a watch or clock.
Drum-shaped container that houses the mainspring.
Filed, turned or obliquely ground surface made to avoid a sharp edge.
The rim that covers the dial (face) and retains the crystal.
Metal part in which at least one of the pivots of the moving parts of a watch usually turns. A bridge is strictly a bar with two supports, and a cock bar with one support. A bar is fixed to the bottom plate by steady-pins. Bars are generally named after the parts they support e.g. barrel-bar, center-wheel bar, etc.
The term identifying movements from their architecture, origin, reference and maker.
Container that protects the watch movement from dust, moisture and shocks. It also gives the watch as attractive an appearance as possible, subject to fashion and the taste of the public. The following are the main parts of a watch case. The middle part, into which the movement is fixed, is the caseband. On the bridge side, the middle of the case is closed by the caseback. On the dial side, it is closed by the lunette or bezel, carrying the glass.
Precious stone, polished but uncut. In French, the word is also used for an embossed ornament on a dial, and of a fancy gilt nail or stud as used by upholsterers.
A complication that shows the day, date and month, correcting for months of different lengths and leap years.
Term identifying movements from their architecture, origin, reference and maker.
An area hollowed out and filled with enamel and then baked on.
A chronograph is a watch that does not only indicate the time of the day in hours, minutes and seconds, but is also equipped with an additional mechanism – operated manually by push buttons –which makes possible to measure continuous or discontinuous intervals of time, from a fraction of a second to 12 hours.
A precision watch, finely set in various positions and temperatures, for which an official certificate has been issued.
Enamel set between strips of metal and baked onto the dial.
A multi-part mechanism providing an additional horological function. Among complicated include minute repeater, tourbillon, perpetual calendar, split second chronograph.
Complete (Full) Calendar
Complete calendar showing date, days of the week and months.
Device with which to wind the watch.
The art of producing a design, pattern or wavy appearance on a metal.
Indicating “face” or plate of metal or other material, bearing various markings to show, in ordinary watches and clocks, the hours, minutes and seconds. Dials vary much in shape, decoration, material, etc. The indicators are given by means of numerals, divisions or symbols of various types. Ebauche
A movement not completely finished or in the rough; not detailed; a raw movement; a movement made up of two plates, a train and a barrel and did not include a dial, case or escapement.
Vitrifiable substance composed of siliceous sand to which oxides are added to give a very wide range of colors suitable for the decoration of metallic surfaces, especially gold, silver or copper. When fired, enamel adheres to the metal and acquires the consistency of glass.
Engraving a watch case with a repetitive design by machine.
The last wheel in a going train; works with the fork or lever and escapes one pulse at a time.
Mechanism fitted between the train and the regulating organ of most timepieces. The purpose of the escapement is to maintain the oscillations of the regulating organ.
In a split-seconds chronograph, a second center seconds hand that can move while remaining superimposed on the first hand, but can be stopped and brought back to zero together with the first hand as it moves; it can also be stopped and brought back to zero together with the first hand.
A spiral grooved, truncated cone used in some watches to equalize the power of the mainspring.
An alloy of copper and 2 to 3 percent glucinum. A hard, highly elastic, non-magnetic and stainless alloy used for making monometal balances, escapements and balance springs.
A watch or clock that strikes the hour, quarter hours and minutes if a minute repeater; a Petite Sonnerie strikes hour only.
Extremely varied pattern of crossing or interlaced lines, giving a decorative effect. It is an especially complicated mechanical engraving technique.
The spring that vibrates the balance. Also called balance spring.
The science, craft, industry and trade concerned with instruments for measuring time.
A bearing made of a ruby or other type jewel; the four types of jewels include: cap jewel, hole jewel, roller jewel or ruby pin, pallet jewel or stone.
Hour numerals that appear through an aperture in a dial.
Gold content of an alloy, on a 24-part scale. Fine gold has 24 karats, consisting of almost 100 percent pure gold; 18-karat gold has 750 thousandths, 14-karat gold, 585 thousandths of gold. The gold content is stamped onto the metal.
A vegetable product, the resin of certain trees found in the Far East (China, Japan), which gives a fine black or red color. The term may also be used to denote articles made of several layers of hardened lacquer.
Curved attachment for holding of fastening an object.
The part of the stop works preventing the barrel from being over wound.
A watch wound daily by winding the crown to tighten the spring.
An accurate timepiece; may have a detent escapement and set in a box with gimbals that keep it in a right position.
Also equal hours; average mean solar time; the time shown by watches.
A watch driven by a spring with a vibrating system that runs purely mechanically, such as a balance or a pendulum.
Far more scratch-resistant than synthetic glass. Hardness 5.
A timepiece that an be made to strike the time in hours, quarters and minutes, by means of a push piece or slide.
A complication that represents waxing and waning of the moon as it circles the earth.
The fully functioning assembly of all the main timekeeping organs of a watch.
A watch that plays a tune on demand or on the hour.
A number of jewels or stones set close together, i.e. paved in diamonds.
A metal plate that supports the bridges and various parts of the movement.
Made smooth and brilliant by very fine-grained abrasives or by rubbing with a burnisher.
Running time in excess of the normal time (24 hours for ordinary watches, 7 days for clocks wound each week) between two consecutive windings. In an ordinary watch, the power reserve usually provides for 10 to 16 hours running.
Synthetic rubies. They reduce the wear and abrasion of the wheels.
Scratch-resistant glass with a hardness of 9. The only harder substance is diamond.
A watch where the spring is tightened by arm movements.
The skin of a horse, shark, ray fish or other animal usually dyed green or a blue green.
Used in a watch whose movement is protected against shocks, i.e. fitted with a shock-absorber system. A.L. Breguet constructed an axial shock absorber called the parachute.
The time of rotation of the Earth as measured from the stars. About 3 minutes, 56 seconds shorter than the mean solar day.
A watch with a mechanism reduced to the minimum material by punching, sawing and milling. Skeleton mechanisms are often provided with fine engravings and chasings. Built in between the transparent dial and glass bottom, they create attractive, decorative watches.
A second hand on the second spring. Can be stopped independently of the switched-on chronograph and return to the current time with the push of a button.
An instrument that only measures intervals of time and does not indicate the time of day.
A watch is considered Swiss-made is its movement is assembled, started, adjusted and controlled by the manufacturer in Switzerland. If at least 50% of the value of all the components (not counting the cost of assembly) are Swiss-made and are subject to technical control in Switzerland according to the applicable system.
A tachymeter (also known as tachometer) measures the speed at which the wearer has traveled over the measured distance – as measured on the highway for instance. The wearer starts the chronograph when passing the starting point and stops it when passing the finish. The wearer can then read the speed in units (in this case, miles) per hour off the tachymeter scale.
A telemeter determines the distance of an object from the observer by measuring how long it takes sound to travel that distance. Like a tachymeter, it consists of a stopwatch, or chronograph, and a special scale, usually on the outermost edge of the watch dial. One application of a telemeter would be determining the distance of a storm from its observer. The wearer starts the chronograph at the instant the flash of lighting is seen, then stops it when thunder is heard. A reading can then be taken to determine the distance of the storm from the observer in miles on the telemeter scale.
Form of watch-movement or case resembling that of a barrel.
Device invented by A.L. Breguet in 1801 to eliminate errors of rate in the vertical positions. It consists of a mobile carriage or cage carrying all the parts of the escapement, with the balance in the center. This delicate, complex mechanism is one of the most ingenious mechanical devices invented by horologists.
A series of gears that form the works of a watch. The time train carries the power to the escapement. The train is used for other functions such as chiming.
An isotope of hydrogen having an atomic weight of three. When treated with tritium, the hour markers or hands become luminous and easy to read in poor light or darkness. It is ideal for diving.
A device that can inform you the current time in your location.