The M. is a long, elastic, spirally wound strip of steel which is used to store the energy needed by a mechanical watch. A M. is housed inside a barrel. The M. develops its greatest torque when it is fully wound. As the M. gradually slackens, the torque declines correspondingly, and this gradual decline affects the watch’s rate. In watches with automatic winding, the M. is continually rewound. This keeps it at approximately the same degree of tautness, thus enabling it to maintain a relatively constant level of torque, which in turn keeps the watch’s rate nearly unvaried. In modern wristwatches, the so-called “Nivaflex” M. is the most frequently used type. Nivaflex is a special alloy which remains elastic and resists breakage for a long time.
Strictly speaking, a watch manufacturer can only describe itself as a manufactory when the firm itself produces at least one ébauche of its own. Within the watch branch, a firm that specializes in the completion and encasing of ébauches which it buys from extramural suppliers is generally known as an etablisseur. The exception to this rule are brands which encase movements that have been made exclusively or expressly for those brands. One such movement, for example, is Chronoswiss’ caliber C.122, an automatic movement formerly used by Enicar. Finally, there also exist modifications of standard calibers which have been developed and executed by commission from various etablisseurs.
Timepieces which are powered by a mainspring and whose oscillating system runs on a purely mechanical basis, e.g. balance or pendulum.
Type of glass which contains minerals and is used for watch-crystals. Advantage: harder (5 on Mohs’ scale) and thus more resistant to scratches than artificial glass (e.g. Plexiglas). Disadvantage: liable to shatter if sharply struck.
A disk rotating beneath an aperture in the dial imitates the successive phases of the moon.
A complete watch-movement (including plates, bridges, gear-train, steel parts, etc.) but without the escapement, balance-wheel, balance-spring, mainspring, dial and hands. Upon request, a M. is available either with or without inset bearing jewels. It is finished in accord with the standards of quality upheld by its maker. Because elaborate production facilities are required to manufacture a M., only a few specialized manufacturers develop and make them.
A complete watch-movement (including plates, bridges, gear-train, steel parts, etc.) but without the escapement, balance-wheel, balance-spring, mainspring, dial and hands. Upon request, a M. is available either with or without inset bearing jewels. It is finished in accord with the standards of quality upheld by its maker. Because elaborate production facilities are required to manufacture a M., only a few specialized manufacturers develop and make them.
A special alloy used for balance-springs. N. doesn’t rust, is immune to magnetism, and scarcely reacts to changes in temperature.