[4K Video] Jaeger-LeCoultre "Geophysic" / The supreme beat of a vintage high-precision machine

This video will move watch lovers and sound lovers around the world to tears! webChronos' "Discovering the World of Luxury Watches through Sound" series features 4K videos focused on the sounds of watches. Enjoy the sounds of watches while savoring the beautiful movements and movement of their hands in 4K resolution. Perfect as background music for your work or as a companion for your after-work drinks. This time, we'll be introducing the Jaeger-LeCoultre Geophysic Ref. E168, released in 1958. Headphones are recommended when viewing the video. Watch writer Shun Horiuchi, who lent his Geophysic watch for the video shoot, also provides a nerdy commentary on the watch.

Jaeger-LeCoultre "Geophysic"

A dial design befitting a high-precision machine

The Geophysic was designed to be worn by scientists participating in the International Geophysical Year, which took place from 1957 to 1958. Equipped with a winding balance spring and the high-precision Cal. P478/BWSbr movement, which is regulated in five positions, the Geophysic produces a pleasant, tuneful sound that is perfectly suited to this project.

Another highlight is the dial design, which is highly legible, typical of a high-precision watch. The center second and minute hands reach the indexes, and both have carefully bent tips.

The pure white dial has a matte finish, which prevents light from being scattered even under strong light sources, allowing you to read the time clearly.

Enjoy this rare model, of which only 1000 were sold over 60 years ago, in high-definition 4K video.

Learn about Geophysic through its origins and the history of the movement

　1958 was the International Geophysical Year. At 11:15 pm on August 3rd of that year, the nuclear-powered submarine Nautilus (SSN-571) became the first manned submarine in human history to cross the North Pole underway. Just eight days later, at 9:47 pm on August 11th, the nuclear-powered submarine Skate (SSN-578) reached the North Pole once again and emerged from the open ice. In recognition of their achievement, the commanders of Nautilus (Major Commander W.R. Anderson) and Skate (Lieutenant Commander James F. Calvert) were presented with a yellow gold Chronometer Geophysic by Jaeger-LeCoultre by a group of Geneva citizens.

　With such a story behind it, the Chronomètre Geophysic was a special watch in every respect for Jaeger-LeCoultre at the time. Let's take a look at the movement to see why.

Movement lineage

　The movements used in Jaeger-LeCoultre's round men's watches from the 1940s onwards, including the Chronometer Geophysic, were mainly the Caliber 449/450 series (records date back to 1940), with Caliber 449 featuring a small second hand and Caliber 450 featuring a spring-loaded center second hand, no date, and a hand-wound, three-hand movement. These movements were also supplied to Vacheron Constantin, who produced watches with additional functions such as a triple calendar and moon phase.

　The main developments in the Cal. 449/450 series are listed below, along with representative calibers.

・Cal.449/450(Hand-wound. 18,000 vph. Diameter 28.25 mm. 449: Thickness 4.05 mm. 450: 4.55 mm).
・Cal.488/SBr(With second hand stop function. 16 jewels. No shock-resistant device. Equipped with "Mark11").

　The movements supplied to Vacheron Constantin are as follows, and are used in the Chronometer Royal.

・Cal.P1007/BS(Hand-wound. Small second. Stop-second function. 18 jewels. Equipped with a swan-neck regulator).
・Cal.P1008/BS(Hand-wound. Center second. Stop-second function. 19 jewels. Equipped with a swan-neck regulator).

　And this is the movement installed in the Geophysic.

・Cal.P478/BWSbr(Hand-wound. Center second. Stop-second function. 17 jewels. Equipped with a swan-neck regulator).

　It has gone through this lineage.

　The Caliber P1008/BS and Caliber P478/BWSbr are like siblings, and the Vacheron Constantin movement has a modified bridge shape with a plump fourth wheel bridge that makes it instantly recognizable as a Vacheron Constantin movement. Naturally, the movements made for the brand, not only those equipped with the Chronometer Royale but also all movements, including the Calibers 453 and 454, which do not have a stop-seconds function, are ultra-luxury, with each part polished to a higher degree.

　Regarding the alphabets given to the movement calibers, the official response from Jaeger-LeCoultre (Editor's note: Mr. Horiuchi inquired directly about the Jaeger-LeCoultre headquarters by email 18-19 years ago and received a response), various documents, and the author's research have been compiled to arrive at the following conclusion.

P: Parashock (with parashock earthquake-resistant mechanism; later K stood for Kif shock).
S: Second Stop (with second hand stop function).
B: Beveled plate (Dial Side: In order to fit the bombe-shaped dial, the outer edge of the back of the day indicator on the main plate is beveled. A indicates that the case back side is beveled, and C indicates that both sides are beveled).
W: means that it has a USA engraving “LeCoultre Co.” (The bridge has LeCoultre Co engraving instead of Jaeger LeCoultre.)
br: Breguet Overcoil Hairspring (winding hairspring, also known as Breguet hairspring. Not marked on movements for Vacheron Constantin).

　The notation "/number" such as Cal.450/1 can be understood as a refinement (minor change) of the movement. Cal.450/4 has undergone four improvements.

The unique features of the Chronometer Geophysic

　Next, I will list the reasons why the Chronometer Geophysic is special, as mentioned above.

1. The year 58, when this model was released, coincided with the 125th anniversary of the founding of LeCoultre in 1833, and so it was designated a jubilee model.
2. 1958 was the International Geophysical Year (July 1, 1957 to December 31, 1958, to be exact), and many scientists from over 70 countries (some say 67 countries) participated in this international scientific research project. The Geophysic was conceived as a wristwatch for these scientists, and was designed with "high-precision chronometer specifications" and "magnetic resistance of 600 gauss and water resistance to withstand a variety of usage environments." Naturally, the nickname "Geophysic" comes from the International Geophysical Year.

　Furthermore, the specifications for achieving chronometer-level precision in the movement highlight its uniqueness.

3. The use of a winding hairspring (Jaeger-LeCoultre ébauche wristwatch movements include Cal. P478/BWSbr, Cal. 488/Sbr for the Mark 11, and Cal. P450/4Cbr. Vacheron Constantin's Cal. 453 and 454 also use a winding hairspring).
4. The use of a swan-neck regulator (this movement is believed to have been the only one used in Jaeger-LeCoultre watches until the appearance of Caliber 879 in the Reverso Septantième in 2002).

　And finally,
5. The bridge is uniquely engraved with "LeCoultre Co" rather than "Jaeger LeCoultre."

　Regarding the bridge with the inscription "LeCoultre Co.", I have long wondered about it, but it has only recently been resolved. As mentioned in point 1, the "125th anniversary" does not refer to Jaeger-LeCoultre, but rather to the 125th anniversary of the founding of LeCoultre, so the bridge is deliberately inscribed with "LeCoultre Co." This is very stylish.

　As mentioned above, movements marked with the LeCoultre Co. designation are marked with a "W." This means that the movement was "cased after being exported to the United States due to customs duties," and is basically unadjusted. Therefore, it is easy to understand that the "W" in the LeCoultre Co. designation is extremely special for Jaeger-LeCoultre movements of the time, which were temperature-compensated in addition to having five positions (Editor's note: At the time, the "LeCoultre" designation existed as a brand for the North American market).

　Records show that the Cal. P478 was tuned to chronometer specifications by Jacques Golay, a watchmaker who was employed at Jaeger-LeCoultre at the time. While the Cal. P478/BWSbr, crafted by him, cuts no corners in areas related to precision, the bridges lack decorations such as Geneva stripes, and polishing, chamfering, and other processing are kept to a minimum. Compared to the Cal. P1008/BS used by Vacheron Constantin, the simpler finish stands out. However, these specifications exude the unique awe of a machine that has been thoroughly tuned for a specific purpose.

Specifications for scientific research projects

　The movement is completely enclosed by a soft iron inner case and dial, making it anti-magnetic.

　The dial is finished with a rough, matte white finish, and is equipped with simple applied indexes with Arabic numerals only at 12 and 6 o'clock. The other indexes are long and thin, which is a common feature of high-precision watches of the same era.

　To meet the diverse research environments of international scientific research projects, ensuring visibility in the dark is a must, and so the hour and minute hands are coated with luminous paint. The hand shapes vary, including dagger and dauphine. The parts of the hands that are not coated with luminous paint are polished, making it easy to read the time on a matte dial. Naturally, luminous paint on the hands alone would make it difficult to read the time in the dark, so the same design should be applied to the indices. However, this model does not feature indices, but rather a small luminous dot on the dial back. However, this dot is very small, and many examples have fallen off over the past 60 years.

　I imagine that many of these watches have had the unfortunate experience of being lost when their cases were unknowingly put into an ultrasonic cleaner during an overhaul. Some have been restored after falling off, but many of these are unnaturally larger than the originals. The stainless steel cases in the video all retain the original dots, making them valuable.

From Geophysics to the Modern "Master" Series

　A total of 1290 examples of this Chronometer Geophysic Ref. E168 will be produced: 1038 in stainless steel, 220 in yellow gold, and just 30 in rose gold.

　One of the dial variations is famous for a design known as a "crosshair." Additionally, there is a model called the "Geophysic Deluxe" Ref. 2985 (available only in yellow gold and pink gold cases) equipped with the Caliber P478/BWSbr. The case diameter is 34mm, and it lacks anti-magnetic features, suggesting it was intended for general consumers rather than scientists. Only 103 examples were produced.

　Geophysic's product year, including the Geophysic Deluxe, is said to have been four years, from 1958 to 1961, and it appears that stock was sold until the late 1960s.

　In 62, Jaeger-LeCoultre followed up the Geophysic with a chronometer watch: the Geomatic, an automatic watch with a date display and chronometer design. This model can be said to be the direct origin of the Master Control series, which continues to this day.

　The Master series, which has a history of well over 60 years, is currently one of Jaeger-LeCoultre's two flagship watches, alongside the Reverso.