In a normal hand-wound watch, the gear train consists of five pairs of wheels with their respective sprockets. The teeth along the periphery of the barrel mesh with the leaves of the sprocket of the middle wheel, which is attached to the same stick that carries the middle wheel. The teeth of the middle wheel mesh with the leaves of the sprocket of the third wheel. The third wheel meshes with the sprocket of the fourth wheel. The fourth wheel engages with the escapement wheel sprocket. The energy flows through the escapement wheel and other parts of the escapement system, eventually reaching the scale, which is thus kept in motion.

A law passed on December 6 on 1886 to regulate the voluntary monitoring of pocket watches formed the legal basis for the so-called "Geneva Seal of Quality" or "Poinçon de Genève." It established strict quality standards for watch production in Canton Geneva. This regulation was made considerably stricter in 1957. From that year on, watchmakers who wanted their watches to bear the coveted mark were required to meet 11 quality standards. The rate accuracy of a watch also occupied the focal point of interest. Wristwatches with movements 30 mm or less in diameter had to undergo an 18-day testing program. Only if the movement met all the criteria did it qualify to carry the "Poinçon de Genève." The most recent version of the regulation dates back to December 22, 1994. The prerequisites for receiving the Poinçon de Genève are the numbering and submission of all candidate movements to the "Geneva Office for Voluntary Monitoring of Watches." The main contents of the regulations concern the determination of twelve criteria regarding the quality level of all components and their workmanship. Among other details, steel parts must have polished edges and satin-finished front surfaces. Screw heads must be polished or circular-grained; slots in screw heads must be beveled. Other provisions specify the details on jewels, gears, and pivots, the affixing of the balance spring to the balance cock, the technical execution of the very important oscillating and escapement system, the care in the workmanship of winding and hand. adjustment of the organs, and the work that must be devoted to the construction of the other components of the movement. Unlike the text of the 1957 law, current regulations no longer set minimum standards for the accuracy of the frequency of the submitted movements. Then as now, however, candidates for the Geneva seal of approval must be assembled and adjusted within the territory of the canton of Geneva.

A rib-shaped embellishment commonly seen given mainly to fine- calibre bridges and cocks. Geneva Waves are applied before the components are electroplated, but remain visible even after that treatment. Geneva waves are generally only found on high-quality movements.

The Glucydur balance is a modern balance that replaced bimetallic balance scales in high-quality watches after the invention of the balance spring. Glucydur balances are made of a copper alloy containing a mixture of approximately 3% beryllium. Glucydur can be recognised by its golden colour. The simpler nickel balances, on the other hand, have a silvery hue. Glucydur balances have a hardness of 380 Vickers; nickel balances have a hardness of 220 Vickers; brass balances have a hardness of 180 Vickers. The higher hardness of glucydur balances makes them more suitable for riveting, balancing and fine tuning.

Greenwich Mean Time. Synonyms are World Time or Universal Time Coordinate (UTC). The prime meridian, i.e. zero degrees longitude, passes from north to south through the centre of the GMT time zone. Mean Time at the Greenwich Observatory in England is used as the standard for navigation and international radio communication purposes.

A precious metal with a specific gravity of 19.5. Gold with varying degrees of fineness is used for jewelry and watch cases. In very fine mechanical watches, gold can also be used as a material for the adjustment screws on the edge of the balance wheel, jewelry mounts, wheels, or even the entire movement.

A gold coating applied to a non-precious support material, e.g., Brass.

Highly complex pocket watch or wristwatch equipped with one or more of the following features: chronograph, perpetual calendar, minute repeater, etc.

A large striking mechanism that, depending on the specific version, automatically emits an acoustic signal to announce the arrival of full, half and quarter hours. A second barrel is integrated into the movement to power this mechanism. As a rule, grand strike timepieces also have a sliding piece that can be moved to deactivate the audible mechanism. The grand strike is often combined with a repetitive movement.

The gravitational attraction of the Earth pulls all bodies towards the centre of the planet. The acceleration experienced by bodies in free fall is measured in 'g'. The influence of gravity on the speed of a mechanical watch should not be underestimated. Especially in pocket watches, which are typically worn in an upright position, gravity can cause significant disturbances in the speed behaviour if the centre of gravity of the balance is not exactly centred on the balance staff. Only if it is absolutely centred is there no point along the edge of the balance that is continuously attracted towards the centre of the Earth with a force greater than all other points along the edge, thus causing both acceleration and deceleration.

After many years of preparation, and soon after the total abolition of ten whole days, a calendar reform ordered by Pope Gregory XIII came into force in Rome on 15 October 1582. This reform eliminated the tiny residual error contained in the Julian calendar, which had been in force since 45 BC and according to which the year was too long for a fraction of a day: 0.0078 x 24 hours = 673.92 seconds too long, to be exact. The Gregorian calendar compensates for this small error by decreasing the leap year by three leap years every 400 years. Whenever a secular year arrives (i.e. a year whose last two digits are 'zero') that is not divisible by 400, that year is not a leap year. Thus, there will be no 29th February in the years 2100, 2200 and 2300 AD.

To engrave, with the aid of a rose engine, the case or dial of a watch with a decorative pattern of thin, sometimes criss-crossed or artfully interwoven lines.

In the early 1950s, the watchmakers at the house of Patek Philippe discovered that the new gyromax balances, which no longer required screws for inertial weights on their rims, could be built with larger diameters without significantly increasing their weight. The larger diameter went hand in hand with an increase in the balance's moment of inertia, which led to improvements in the frequency performance of a watch. Patent protection was granted to the 'Gyromax' balance on 31 December 1951. On this type of balance, eight disc-shaped regulating elements are carried on axially arranged pivots. The elements can be rotated. This exceptional development can be seen as the forerunner of the modern ring scale, which has no screws.