180 YEARS OF

1942
Chronograph with
Hour Counter
CALIBER 13ZN
Good is the enemy of better,
and nowhere is this adage
more true than when it’s
applied to Longines’s movements.
In 1936, the company
began development of a new
model to follow in the footsteps
of chronograph Caliber
13.33, which after 23 years in
production was still successful
but had become too expensive.
Various devices for Caliber
13ZN had already been
completed by the autumn of
1935, so models containing
the new movement could be
launched at the peak of the
chronograph’s popularity. A
great advantage for Longines
80 | WatchTime LONGINES SPECIAL
was that only a few of the
brand’s competitors had manufacture
calibers of this type at
their disposal. Available with
either one push-piece or two,
Caliber 13ZN was six millimeters
thick and had a fly-back
mechanism, a column wheel,
as well as a screw balance with
a self-compensating Breguet
hairspring that oscillated at a
pace of 2.5 hertz, and a 30minute
counter that advanced
at half-minute intervals. Hourcounters
became fashionable
in the early 1940s, so Lon -
gines’s technicians created a
modified version of Caliber
13ZN, first marketed in 1942,
which had its 12-hour counter
at 3 o’clock. Longines also
enhanced the legibility of the
60-minute counter by repositioning
it in the dial’s center.
Like its forebear, this movement
was, unfortunately, too
expensive, so Longines soon
began developing a successor:
Caliber 30CH celebrated its
premiere as the brand’s last
chronograph movement for
wristwatches in 1947.
1945
First Automatic
CALIBER 22A
ere were very few rotor-wound calibers for wristwatches
in the 1940s. To avoid infringing on patent
protection, many watch brands hurriedly created hammer-wound
movements with buers to brake the rotors,
but Longines opted not to pursue this route. Instead, the
company concentrated on a mechanism with an oscillating
weight that could swing freely. Of course, Longines,
too, had to contend with the obstacles presented by
Swiss patent law. e way to overcome them was with a
system in which the rotor wound the mainspring in both
directions of rotation. is bidirectional automatic
winding system was integrated in Caliber 22A: launched
in 1945, it had an indirect central seconds hand and
amassed 36 hours of power reserve. Its geometry is
essentially based on Caliber 27, which debuted in 1944.
To achieve an acceptable overall size for Caliber 22A,
Longines had to miniaturize the basis, onto which the
brand mounted the self-winding subassembly with a
patented click changer. Right from the start, the watchmakers
had detected a potential weakness: the relatively
thin sta on which the oscillating weight was borne.
To counteract possible breakage, a heavy metal segment
was elastically axed to the central rotor’s disk. e entire
device couldn’t be very at, but an overall height of
5.65 millimeters was feasible, and acceptable at the time.
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