ADJUSTED. A watch is said to be 'adjusted in 5 positions' if it has been rated in the two horizontal and three of the possible vertical positions - i.e. dial up, dial down, pendant up, pendant left, pendant right and pendant down. 'Adjusted for temperature' means that the compensation has been observed in at least three temperatures.

ADJUSTABLE POTENCE. See P1.125. See POTENCE

AFFIX. A small bimetallic blade, one end of which fixed to the rim of the balance: used to correct the temperature compensating properties of the main compensating arrangement.

'ALL-OR-NOTHING' PIECE. In a repeating watch, device which ensures that the striking is released only if the lever or push-piece for the repeating action is fully depressed. Without this mechanism, the actuating lever or push-piece is insufficiently :pressed an incorrect number of hours is sounded. lith this improvement, the watch has to strike all or nothing. Both Tompion and Quare incorporated it, though Julien Le Roy is often credited with the invention.

AMPLITUDE. The maximum angle by which a balance swings from its position of rest. By observing the arms of a balance it is possible to estimate this angle. See ARC.

ANTI-MAGNETIC. Unaffected by magnetism. If those parts of a watch most affected by a magnetic field (balance, balance spring and escapement) are made of non-magnetic materials the watch is termed 'anti-magnetic'. The earliest non-magnetic balance springs were gold as used by John Arnold. Subsequently palladium alloy was invented by C. A. Paillard in 1877.

APPLIQUE. Applied ornament to a case, or applied chapters, numerals or decoration to a dial.

ARBOR. The spindle, shaft or axle upon which the wheels of a watch train are mounted.

ARC. The arc of a balance is twice the amplitude (q.v.). A balance with an amplitude of 270 degrees has an arc of 540 degrees (1½ turns of the balance).

ATTACHMENT. The 'point of attachment' or 'pinning-point' is the point at which the balance spring is pinned to the collet on the balance staff. This is of importance in the timing of a watch.

AUTOMATON WATCH. A watch with animated figures, actuated by the going, striking, musical or repeating train. See JACQUEMART.

AUTOMATIC WATCH. A watch which is wound by the movement of the wearer. Also known as a 'self-winding' watch. John Harwood made the first self-winding wrist watch in about 1928. Patent No 218,487 of 1923.


P1.125. Movement plate showing adjustable potence and adjustable bearing for crown wheel. From repeating movement by Romilly, Paris. circa 1765.

AUXILIARY COMPENSATION. An additional and subsidiary compensation sometimes fitted to a bimetallic balance to eliminate the middle temperature error (q.v.).