Time Zones and GMT
The idea to introduce a single global time reference system is commonly attributed to Sandford Fleming, a Scottish born Canadian railway engineer who, in 1879, proposed to subdivide the world in 24 time zones. As strange as it may sound, the idea came as a consequence of missing a train while traveling to Ireland, because a printed schedule listed “p.m.” instead of “a.m.”
Sandford’s system became operational in Canada in 1883 and was adopted as a common standard worldwide by the International Meridian Conference in Washington a year later. By 1929, all major countries in the world had accepted it.
What does “GMT” mean?
GMT is an acronym for Greenwich Mean Time, which was the local time of the zero meridian of the London suburb of Greenwich. From here, the British Post Office broadcast time signals to the whole country in order to allow people to adjust their clocks.
Moreover, since the 1960s, all atomic clocks have been synchronized to Greenwich Mean Time, which has since been otherwise known as "Universal Time Coordinated" or UTC. Today, UTC is the global reference time for any time synchronization.
Why a GMT watch?
After the invention of the railway, the 20th century experienced an even more significant revolution in the field of transport. The arrival of aviation effectively canceled the barrier of distance. In fact, in the 1960s, airliners flew through the sky at more than 800 km / h, a speed totally off the scale by rail standards.
A 3000 miles London to New York flight took around 7 hours in 1960 (more or less as much as nowadays), moving across 6 time zones. In the same years, to cover a similar distance, such as on a coast-to-coast trip in United States from New York to San Francisco, it took 83 hours, but only covered 4 time zones. Therefore, for the train conductor it was not an issue to keep track of local time, because crossing a time zone happen just a few times during the travel. For a jet airliner pilot, this was at least impractical.
To solve this problem, the American airline company PanAm partnered with Rolex to provide their pilots with a watch that could simultaneously follow local time and keep track of the time of arrival. The GMT Master was the answer.
How does GMT work?
The GMT module consists in an additional hand, usually with an arrow shaped tip, that makes one revolution every 24 hours, and allows to keep track of a time zone other than the local time, which is monitored by the hour hand (that completes a full cycle in 12 hours, of course).
Mechanically, the early GMT modules were quite simple: the GMT hand was anchored to an additional gear coupled with to the hour one. The GMT hand followed local time on a 24-hour scale displayed on the bezel, which was derived from diving watches. To monitor a second timezone, you just needed to rotate the bezel according to the relating time difference.
Hands kit from the new Nereide GMT 39 collection
Modern GMTs add the possibility to keep track of a third time zone using the dial indices as a reference, because the GMT hand can be set independently from the hour hand.
Aside from the fourth hand, the single feature that makes GMT watches unmistakable is the bi-color bezel. It comes in two equally divided halves, usually marked with a dark and a light color, respectively covering the night time and daylight hours.
A movement for elite watches?
Among mechanical watches, GMTs has always been categorized as “luxury”. Their additional special function has placed them among the so called “complicated” timepieces and prices have always been on the high-end side, especially if they also featured automatic winding.
However, in mid-2022 one of the biggest watchmaking companies in the world, Seiko, revealed the NH34A. This is the first truly affordable GMT movement released by a major producer.
We are among the first companies in the world to feature this caliber. Thanks to Seiko quality and reliability, the new Nereide GMT lives up to one of our cardinal principles: to produce "quality but affordable" watches.
Four color variation will be launched on July 25th 2022: teal blue, light anthracite, absolute black and pearl grey with rose gold accent. Placed under an anti-scratch sapphire glass with anti-reflective coating, all the dials boast a sunburst finishing and are enclosed in a 39 mm 316L stainless steel case, which is water resistance up to a 200 m depth and sealed by a screw-down crown.
All technical specifications:
- Case material: 316L Stainless Steel
- Dimension: Ø39 mm, lug to lug 45.50 mm
- Thickness: 13.3mm, glass included
- Movement: Seiko NH34A GMT Automatic
- Functions: GMT, date
- Vetro: zaffiro con trattamento antiriflesso
- Luminous pigment: BGW9 Super-LumiNova®
- Bezel: BK7 Glass Insert, 120 clicks
- Water resistance: 20ATM (= 200mt)
- Bracelet: Canova
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