Gold-plated club-tooth lever wrist-watch with centre-seconds and alarm with gold-plated expanding bracelet

Description — British Museum

Movement with club-tooth lever escapement. Silvered-metal dial with an outer-ring calibrated 12x10-60 for centre-seconds; raised gold Arabic hour numerals 2-12, alternating with triangles for the odd numbers. Gold-plated hour and minute hands;… blued-steel centre-seconds hand and alarm setting hand with black arrow-head tip. Gold-plated case with snap-on inner and outer backs; stainless-steel inner with spotted decoration. Gold-plated metal and stainless-steel expanding bracelet.

Curator's comments — British Museum

Comment from Richard Good, Catalogue of Watches in the British Museum. Vol. V (Unpublished manuscript) Made by Vulcain Switzerland, c. 1950 Alarm Wrist Watch with a club tooth lever escapement Signature: On the dial 'VULCAIN cricket'. Case: A rolled gold case with on the portion of the case beneath the spring lug a W with an extended seriph with beneath this long stroke '10KGOLDFILLED' A stainless steel back pierced to let out the sound with on this back a W with an extended seriph with beneath this long stroke 'STAINLESS STEEL'. Inside the back is 'VULCAIN Wadsworth 10K. GOLD FILLED BEZEL STAINLESS STEEL BACK W114591 SWISS PATENTS U.S.PATENT APPLIED FOR'. With the case a bracelet, gilt on the front and stainless behind, every link marked SPIEDEL PAT 2,689,450. Dial & Hands: A silvered dial with raised gilt hour numerals 12, 2, 4, 6, 8 and 10 and with batons between. A black minute circle with outside of it a black alarm setting ring calibrated in 10 minute steps and the minutes numbered 10, 30 and 50. Gilt hour and minute hands a rhodium plated alarm hand with a tip painted black and with a blued steel centre seconds hand. Movement: Under the outer back is what appears to be another back, this is the bell and it carries inside a post on which the alarm hammer strikes. This has to be correctly positioned when the bell is replaced and to this end there is a dot which has to be aligned with a dot on the case. Ebauche Marks: 252 030 under the dial and beneath the balance On the inside of the front plate is the Vulcain trade mark and 120. Frame: On the alarm barrel ratchet wheel is 'cricket' and three small circles, on the going barrel ratchet wheel is 'VULCAIN GRAND PRIX'. On the barrel bridge is 'SWISS PATENTS U.S.PAT. APPL. FOR' and 'UNADJUSTED'. On the train bridge is 'VULCAIN WATCH Fy SEVENTEEN 17 JEWELS SWITZERLAND'. There is an import mark on the balance bridge 'VOH'. A cock for the escape wheel and a bridge for the pallets. Barrel and Mainspring: There are two going barrels, one driving the alarm train and the other for the going train. The going barrel has a recessed cover. Barrel: internal diameter 11.3 mm., height 1.47 mm. Mainspring: height 1.43 mm, thickness 0.11 mm. Barrel Arbor: diameter 3.48 mm., snailed. Hooking: Milled from the barrel wall. The alarm barrel also has a recessed cover Barrel: internal diameter 9.3 mm., height 2.0 mm. Mainspring: height 2.0 mm., thickness 0.07 mm. Barrel Arbor: diameter 2.4 mm., snailed. Hooking: Milled from the barrel wall. Train: All the wheels gilded, the centre, third and fourth wheels with five crossings. The steel escape wheel with four. Jewelling: Jewelled bearings from the third wheel onwards, all the jewels pressed in. Ruby endstones of a special shape to equalise the friction between hanging and lying. The endstones are coned with the apex of the cone set off centre to the pivot hole in the jewel so that the pivot is pushed to one side as it works. Escapement: A straight line layout club tooth lever escapement with short lever, double roller and D-shaped impulse pin. The exposed pallet stones have flat acting faces. A steel escape wheel with four crossings. An equidistant locking escapement. No. of teeth embraced 3½. Balance & Spring: a monometallic balance with brass screws. Balance diameter 10.5 mm, thickness 0.6 mm. A 'self compensating' flat spiral spring with 12 ½ turns. Means of Regulation: An index on the balance bridge and a divided scale with 'F' and 'S' engraved on the balance cock table. However the index cannot register against this scale which is largely covered by the a T shaped piece of polished steel. Train Counts and Beat Rate: Great wheel 72 (barrel) Centre wheel 49 pinion 14 Third wheel 75 pinion 7 This wheel also drives the idle centre seconds pinion of 7 which is furnished with a drag spring. Fourth wheel 70 pinion 7 Escape wheel 15 pinion 7 Beat rate 18,000 Motion work: cannon pinion 12 minute wheel 32, minute pinion 8 hour wheel 36 Winding System: It will be found that the minute and hour hands can be set in the normal way although they can only be set forwards. To set the alarm the push piece A is pressed and this causes the winding button to withdraw. The alarm hand is then set by turning the button in the clockwise direction - this causes the alarm hand to rotate in an anticlockwise direction. If the winding button is turned in the wrong direction both when setting the hour and minute hands or the alarm hands no harm can be done as the button just freewheels. When the alarm hand has been set the winding button is pressed back and this automatically releases the alarm setting mechanism and the push piece A will jump out into its normal position. If the alarm is not required the push piece A should be pushed half way in which will in turn cause the winding button to move half way to the hand set position. This is a neutral position for the button and no gears are engaged. Alarm work: The alarm setting wheel has 45 teeth. Dimensions: Case diameter 33.2 mm., height 12.5 mm., over the glass. Movement: Diameter 28.7 mm., height 7.5 mm. Provenance: Purchased in 1988 with the aid of funds from the Dingwall Bequest. Note: The first wrist watch with an alarm was developed by Eterna about 1913. One of the problems was to achieve a satisfactory volume of sound. The problem was overcome by Vulcain around 1947. The watch sounds for some 25 seconds the volume of sound being about the same as that from a small travel alarm. The effect is achieved by using a double back. In 1958 the firm developed a version for ladies 'The Golden Voice' alarm watch. The figure shows the Vulcain cricket with its two barrels wound by the one stem. The wheel K moves over automatically when the direction of rotation of the stem is changed. Fig 2 shows the arrangement beneath the dial with the conventional positive stem set keyless work. The push button beside the stem allows the owner to set the alarm hand. Fig 3 shows the section through the w.