B-Uhr project: The history of Observation watches | Part 2.
Marine chronometers and observation clocks
In addition to the marine chronometers with a gimbal-mounted clockwork and thus a rate regulator that oscillates always in a flat position, the ship’s crews also had the so-called deck or observation clocks at their disposal.
This was needed to transfer the exact time from the seconds pendulum clocks hanging in naval observatory to the marine chronometers. They also served to compare the results of cutlery recordings using sextants with the time of the marine chronometer screwed tightly to the bridge. As a rule, these instruments were designed as pocket watches, stored in wooden cases or metal containers.
Compared to sailors, pilots were only on the road for a relatively short time, if only for reasons of fuel supply. During the war they also mostly moved in the so-called “near zone”. With both hands on the stick, they needed a different type of clock during combat operations or for precise navigation to read the time quickly, reliably and to the second.
The pocket observation watches common on board ships simply did not serve the purpose. Instead, it had to be possible to wear her timepiece either on the arm or on the thigh over the aviator’s gear. So only sufficiently large instruments equipped with long leather straps came into consideration.
Because the relevant departments and high command did not want to leave anything to chance during the Second World War, they precisely defined the construction, horological execution and regulation of this type of clock. Her works were to be housed in gray cast bronze or steel cases with a diameter of 55 mm. The large or protruding winding and pointer crown had to be operated with gloves.
The inside of the base bore the following engravings: type, device number, serial number, requirement mark and manufacturer. The uniformly black dials were labeled with radium luminous material. All movements had a centrally located seconds hand with a counterweight and a balance stop device for setting the time to the second.
Before delivery, every watch without exception had to be checked by a sea control or an official test center in accordance with international regulations. In this context, they had to meet the criteria for issuing an official gang ticket. For this reason, it always had to be fine-tuned in six positions (dial above and below, crown on the left, right, above and below) and at three different temperatures.
Already at the turn of the century, A. Lange & Söhne, Glashütte, founded in 1845, was of the greatest importance in the production of observation watches. The Saxon manufactory not only produced the highest quantity, but also delivered considerable numbers to the testing institutes.
In the 1930s, and especially during the Second World War, the need for observation timepieces increased so rapidly that A. Lange & Söhne could no longer satisfy it with the best will in the world. That is why the license was granted to companies such as Deiter in Essen, Felsing in Berlin, Huber in Munich and Wempe in Hamburg to reassemble and clad Glashütte caliber 48 raw works.
Because it wasn’t enough, the authorities ordered the pilot’s wristwatches from other manufacturers. In total, the German military used five different types of observation wristwatches
Next episode: “The big five”.
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Gisbert L. Brunner, born in 1947, has been working on watches, pendulum clocks and other precision timepieces since 1964. During the quartz clock crisis of the 1970s, his love for the apparently dying-out mechanical timepieces grew. His passion as a hobby collector eventually led to the first newspaper articles in the early 1980s and later to the by now more than 20 books on the topic.
Amongst others, Brunner works for magazines such as Chronos, Chronos Japan, Ganz Europa, Handelszeitung, Prestige, Terra Mater, GQ and ZEIT Magazin. He also shares his expertise on Focus Online. Together with a partner, he founded the Internet platform www.uhrenkosmos.com in 2018. After the successful Watch Book I (2015) and Watch Book II (2016), the teNeues publishing house published the Watch Book Rolex, written by Gisbert L. Brunner, in June 2017. The book has appeared in German, English and French and has already been reprinted several times due to high international demand.