By Pierre M. Maillard

Breguet and the world's smallest automatic chronograph

Patek Philippe's ladies' complication

Kelek's small Lady automatic chronograph

During Basel 1998, Breguet presented its Ladies' Marine Chronograph equipped with a Nouvelle Lémania 550 automatic movement. This caliber, with date indicator, is the smallest chronograph movement in existence. Its total diameter is 23.9mm and its fitting diameter is 23.2mm, with a thickness of 6mm.

The caliber 10.5''' offers a very exceptional dimension-performance ratio. Vibrating at 21,600 per hour, it has a working reserve of 45 hours.

Small seconds are shown at 6 o'clock. Chronographic functions include the seconds counter in the center, minutes at 3 o'clock and hours at 9 o'clock. They are operated by a column wheel controlled by a pushbutton located at 2 o'clock.

The column wheel operates the chronograph mechanism by coordinating the execution of the three measures of time: start, stop and start from zero. The zero start is controlled by a pushbutton at 4 o'clock. Additional functions can be added such as a rattrapante (flyback) function.

The exemplary finishing of this movement can be seen in the circular grain design of the wheels as well as the Côtes de Genève pattern.

by Breguet

After its "small complications", intended to simplify and optimize certain mechanical functions such as the perpetual calendar, Patek Philippe is now offering a new ladies' watch with moon phases and a small seconds hand, Reference 4857.

Contrary to other watchmakers who feel that women are not really interested in the mechanical watch, especially manual-wind versions, Patek Philippe

is convinced that its female clientele are showing "an increased interest in complicated timepieces that are technically sophisticated".

With this in mind, the Geneva firm has integrated lunar phases into its smallest manual-wind movement, the Caliber 16-250. With a diameter of 16.3mm and a thickness of 2.95mm, it is the smallest mechanical movement ever produced by Patek Philippe, and is the only one in its size category to earn the prestigious mark of the Poinçon de Genève (Geneva Seal).

The addition of moon phases necessitated the integration of three mechanical functions using a single multi-armed, pivoted lever, which governs the entire moon-phase operation, including manual reset. This lever increases the total thickness by only one-half millimeter.

Another particularity worth mentioning is that the moon phase indication reproduces

the actual lunar cycle of 29 1/2 days. Its easy-to-read display is placed at 4 o'clock.

Diameter: 16.3 mm

Overall diameter: 20 mm

Height (including moon disc): 2.95 mm

Number of parts: 115

Number of jewels: 18

Maximum power reserve: 38 hours, manual-wind

Balance: Plain

Balance spring: Flat, mobile stud

Frequency: 28,800 vibrations/hour

Moon advance: At 09:00 and at 21:00

Hallmark: The Geneva Seal

Already in 1992, Kelek had presented what was up to that time the smallest automatic chronograph in its category. Since then it has been overtaken in the race towards miniaturization, but this movement still remains one of the most important references in this domain.

Kelek is undeniably the Swiss specialist in the field of automatic mechanical chronographs. Developing its movements in coordination with the firm Dubois-Dépraz, Kelek has perfected a modular system allowing for all sorts of combinations.

The 11 1/2 line Caliber 10 000 has a diameter of 26.2mm and a thickness of 6.55mm. These dimensions are used for the manufacture of watches considered either "unisex" or ladies' timepieces.

This modular mechanism can be adapted either directly to the ETA 2892/2 automatic caliber or to another more sophisticated automatic movement, by modifying the bottom plate.

Its modular construction allows any number of other indications to be added, in addition to the hour, chrono and date functions.

An advantage of this modular system concerns the after-sales service. The movement is accessible simply by undoing three screws, without dismantling or upsetting the chronograph mechanism.

Until this device came along, manufacturers involved in miniaturization hit up against the problem of energy consumption. It was too high for an 11 1/2''' movement to operate an automatic chronograph. The lack of power of the spring motor was compensated for by lowering the resistance of many of the gears. This original conception also permitted an improvement in readability of the chronograph indications, a recurring problem in the domain of ladies' watches.

The Ladies' Minute Repeater Carillon is without a doubt the smallest minute repeater on the market today.

Ten years of research and development were necessary to perfect this exceptional mechanism, and to place this first repeater watch within the reach of women attracted by mechanical watches.

Of an exceptional density (340 pieces in a space of 2cm3), its movement has a fitting diameter of 22.30mm and a thickness of 5.00mm. It features a working reserve of 48 hours and small seconds subdial at 6 o'clock. The hours, quarter-hours and minutes are indicated by different pitches and the number of chimes.

One of the major difficulties confronted by the technicians at Audemars Piguet was to obtain a pure quality of tone which depended on various parameters, including the size of the bell and the type of materials used.

To solve this problem, they perfected an artisanal technique permitting construction of the bell in one piece, composed of a small rod whose rounded end is connected to a square base. This eliminated the need for soldering which would have affected sound quality. Protected from vibrations, this one-piece bell permits very high quality resonance. This timepiece is the only small wristwatch of its kind to possess three hammers and three bells. A subtle balance allows the precise calculation of the power of the strike: too strong, it muffles the sound; too weak and the sound becomes inaudible.