Review: Jaeger LeCoultre Geophysic True Second

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We covered the Press Release with our initial impressions on the Jaeger LeCoultre Geophysic True Second earlier. In this article, we delve deeper into the watch. We discover the roots of this amazing line of watches and discuss the aesthetics, explore the seconde morte mechanism. 

 

The Jaeger LeCoultre Geophysic – a bit of history

 

The Jaeger LeCoultre Geophysic is one of the gems from the manufacture’s archives. It traces back to the original Geophysic in 1958  which was created to celebrate JLC’s 125th Anniversary and the world’s first “International Geophysical Year”.  The International Geophsical Year was a scientific operation participated by some 67 countries to lay the groundwork for sharing knowledge in the Earth sciences. They set up numerous bases in the Arctic. With its precision, toughness and resistance to magnetic fields, the Geophysic Chronometer E168 was created and accompanied the scientists on their explorations. Another model was the 2985, dubbed Geophysic Luxe, of which only 103 were made.

Jaeger-LeCoultre equipped the Geophysic with the caliber 478BWSbr which offers a guarantee of the greatest accuracy: indirect central seconds, stop second, Glucydur balance wheel, swan-neck adjustment system (with regulator spring and setting screws), shock absorbers, precision end curves, anti-magnetic escapement, unbreakable spring, 17 jewels, a silvered dial, appliqué hour-markers and luminous filled hands. It was then, the most accurate and most watch ever made.

Production was very small and only approximately 1000-1200 stainless steel pieces were made in 1958, and an additional 30 were made in solid gold. Production was only for one year, and in 1959 it was replaced by a simpler, more common and automatic watch known as the Geomatic. As a result, the original Geophysic commanded a high premium in auctions, Christie’s sold one E168 for £12,600 in March of 2010 in a charity auction to benefit UNESCO World Heritage Centre.

Fast forward 2014, Jaeger LeCoultre reintroduced the Geophysic 1958 Limited Edition. The new watch was faithful to the old, but was not a replica. The case was resized from 35mm to 38.5mm. The new watch had the JLC caliber 898/1, their top of the line automatic movement. Many of the advanced features of the original JLC 478BWSbr were also present: hacking seconds, shock protection, a special gear system for smooth torque, a balance with micro screws for fine regulation, as well as ceramic bearings on the rotor and an anti-magnetic soft iron cage.  And was available in an edition of 800 in steel, 300 in rose gold and 58 in platinum.

 

Enter the Jaeger LeCoultre Geophysic True Second

 

Details of this new release is found in our coverage of the Press Release found here.

 

Jaeger LeCoultre Geophysic True Seconds in stainless steel case.This version comes equipped with a stainless steel butterfly deployant clasp.

Jaeger LeCoultre Geophysic True Seconds in stainless steel case.This version comes equipped with a stainless steel butterfly deployant clasp.

 

Aesthetically, it remains very clean and elegant. The original cross hair design with the numerals 12, 3, 6, 9 in Arabic are now replaced with even cleaner bar markers. The sword hands remain, and are now filled with SuperLuminova. The watch is equipped with a central seconds hands and a date aperture at 3 shows the date. The case is now 39.6mm in diameter. JLC makes a fuss in ensuring that it is 39.6mm and not 40mm, as a nod to the scientific notation to one decimal point accuracy also points to the watch’s intended (or aspirational) application.

 

Jaeger LeCoultre Geophysic True Seconds in rose gold.

Jaeger LeCoultre Geophysic True Seconds in rose gold.

 

The hacking mechanism deserves a mention. When the crown is pulled out one click, the watch is not hacked, but the hour hand can be adjusted  in one hour increments but not the minutes. This handy feature allows one to change timezones without losing the synchronized timing. The minutes can only be adjusted when the movement is hacked on the second click.

As seen in the zoom in photograph below, the dial is smooth, but has a granular like structure which is a particularly beautiful play with the light at different angles.

 

Dial detail of the Geophysic True Second.

Dial detail of the Geophysic True Second.

 

The movement is now the JLC caliber 770. This is a well designed and beautifully constructed automatic movement equipped with a gold rotor with the stylized JLC logo.

 

JLC caliber 770.

JLC caliber 770.

 

 

The movement is nicely finished, and carries the traditional decoration from the manufacture. The balance wheel is held in place by a bridge instead of the more classical cock in an effort to ensure greater stability.

This is a rather interesting movement. First, it uses a special balance wheel. Called the Gyrolab by JLC it has an unusual shape. Instead of a circular balance, it looks like a curved, stylized H.

As the balance is already anti-magnetic due to the selection of the materials used, a soft iron core is not necessary for the Geophysic True Second, and a sapphire crystal display back can be fitted.

 

The Gyrolab balance wheel.

The Gyrolab balance wheel. JLC photo.

 

According to JLC, the shape of the balance wheel allows for better precision. As it is also smaller, it is also more efficient. The balance spring is flat, and two sets of screws are presumably used for regulation and poising. This Gyrolab balance was first seen in the experimental Extreme Lab Concept watch circa 2007, but the Geophysic will be the first implementation in a series production watch.

 

On the wrist the 39.6mm diameter and 11.5mm thich wears very nicely indeed.

On the wrist the 39.6mm diameter and 11.5mm thich wears very nicely indeed.

 

Also of interest in the movement caliber 770 is the True Second mechanism. This is a seconde morte mechanism, which allows the seconds hand to jump forward one second a time. After one whole second elapsed, the hand makes one jump, and rests (morte = French for dead) for a whole second before making the next jump. To the uninitiated, this looks like the seconds hand of a quartz movement. However, in the quartz movement, the second hand advances once a second in an effort to conserve battery power. Power to continuously move the second hand is higher than one which only moves once a second.

In a mechanical watch, a complicated mechanism is needed to achieve this. Arnold & Son, Habring2, De Bethune, and FP Journe and Gronefeld also make a watch with this feature. The method JLC chose to implement the seconde morte is different and interesting.

As the original Geophysic uses an indirectly driven center seconds hand, the True Seconds as well.

 

The JLC caliber 770. The blue arrow shows the wheel train's fourth wheel. A direct seconds hand can mounted on this wheel and would appear as a subsidiary seconds hand on the dial side. For a center seconds hand watch, the third wheel drives a secondary fourth wheel, shown by the red arrow. This in turn drives the center seconds wheel pinion, where the seconds hand is attached on the other side. Note the spring under the red arrow. This is the remontoir for the seconde morte.

The JLC caliber 770. The blue arrow shows the wheel train’s fourth wheel. A direct seconds hand can mounted on this wheel and would appear as a subsidiary seconds hand on the dial side. For a center seconds hand watch, the third wheel drives a secondary fourth wheel, shown by the red arrow. This in turn drives the center seconds wheel pinion, where the seconds hand is attached on the other side. Note the spring under the red arrow. This is the remontoir for the seconde morte. JLC rendering with Deployant arrow markers.

 

Shown above, the blue arrow indicates the wheel train’s fourth wheel. The 770 is traditional in this regard, and the fourth wheel turns at one revolution a minute. This is the classical method of a direct mounted seconds hand, by attaching the hand to the dial side pinion of the fourth wheel. We can easily see that this pinion will appear non-centered on the dial side, and hence all classical directly driven seconds hand like this will be a subsidiary seconds hand.

To implement a classical center seconds hand, two additional wheels are required (at a minimum). We leave the reader to work out why two additional wheels, instead of only one.

The JLC caliber 770 is not a classical center seconds movement. As seen in the photograph above, the third wheel which drives the pinion of the fourth wheel (blue arrow), and also drives the pinion of another wheel. This wheel is not in the power train, and hence indirectly driven.

 

The True Seconds mechanism of the JLC caliber 770

The True Seconds mechanism of the JLC caliber 770. JLC animation.

 

Note on the second fourth wheel, as marked by the red arrow, is attached a hairspring (the remontoir spring). The wheel is blocked by a click mechanism and this prevents it from moving. As the wheel train moves, it then winds the spring. One small step every 1/8th of a second. The click mechanism is connected to the wheel train, and automatically releases once every second. As it does so, the wheel advances one small step forward, completing 60 steps per revolution. This gives the staccato step effect to the seconds hand.

The F.P. Journe Soverain Tourbillon d’Egalite also utilizes a remontioir to achieve its seconds morte. But the Journe implementation uses a linear spring instead of the hairspring chosen by JLC. And since Journe’s remontoir is in the power path, it achieves an additional function of being a constant force escapement.

 

The JLC Geophysic True Seconds in rose gold and steel.

The JLC Geophysic True Seconds in rose gold and steel.

 

Concluding thoughts

The Jaeger LeCoultre Geophysic True Second is an amazing watch. The design is very appealing. Its proportions are near ideal, and the execution very very good. The movement which powers it also bring special interest. The seconde morte implementation of a remontoir is very interesting. The pricing is also of great interest. It is available now from JLC Boutiques and Authorized Dealers at a retail price of only S$13,300 for the steel cased version and in pink gold it costs S$25,900.

 

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