Explore More Articles
IWC Oils
Time That Runs Like Clockwork

Depending on the stresses and strains to which they are exposed, around 50 points in the movement are treated with oils and greases developed especially for use in wristwatches.

Test Lab

At IWC Schaffhausen, new watch models are put through a gruelling test program involving up to 50 separate stages that include long-term immersion in warm salt water and being locked away in an environmental chamber. All this guarantees that they will be equipped for everyday use – and much more – when they finally reach their future owners.

Sound_check_engine_AMG_972x426
Sound Check

How the engineers at Mercedes AMG in Affalterbach, southern Germany, create the right engine sound.

HALF_WAY_TO_THE_MOON_Trucks_972x426
HALF WAY TO THE MOON

For the MERCEDES AMG PETRONAS Formula One™ Team, following the Grand Prix circus means transporting 30 tons of material in 10,000 individual parts and at least 60 employees to venues on five continents. Of course, they have to ensure that everything arrives there on time what calls for a system and improvisation in equal measure.

Grande Complication Dial Explained
Small World

Time moves the world. The IWC Portuguese Grande Complication is an understated, beautifully designed way of summarizing time as the motor of all change: a time machine that shows a tilted globe on the dial.

89800 Calibre Movement
Eternity in Digits

The IWC-manufactured 89800 caliber, which made its debut in 2009, redefined the digital date display. The triple-disc mechanism in the perpetual calendar features large-format displays for the date and month and, slightly more discreetly, the leap year cycle. All are ingeniously synchronized.

Top Secret

In a small town in central England, over 500 specialists spend their time developing and building silver arrows for the MERCEDES AMG PETRONAS Formula One™ Team. Almost every one of the 3,200 parts in each car is custom-made.

Ingenieur: the story of a legend

When the Ingenieur from Schaffhausen was launched in 1955 it created a storm. But its actual history goes back much further: to 1888.

Experiences

Tradition still sails

Navigation with the sextant

Text — Martina Wimmer Photos — Paul Ripke and Martin Timmermann Date — 1 January, 2010

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—Despite a wealth of electronics, modern ships are still required to have a sextant on board as part of their standard equipment. Tradition-steeped Cassens & Plath in Bremerhaven meticulously handcrafts these high-precision instruments

Every ship sailing the seas should be able to find its way without reference to a satellite. A magnetic compass and sextant are therefore essential equipment on board

A sextant is an optical measuring device used to determine the angle between a celestial body – preferably the sun – and the horizon, and from this to determine the position of a ship.

The basic principle, construction and function of the sextant have remained unchanged since its invention in the 18th century. Forerunners of the sextant – the astrolabe, quadrant and Jacob’s staff – had served seafarers since the 15th century to gauge the sun’s position. But it was only the use of mirrors, and double reflection, that made it possible to establish the sun’s exact angle from the horizon. It later emerged that the idea had been the brainchild of Isaac Newton. But his ideas, put on paper in sketches, were ignored and only published posthumously in 1742.

Working independently of one another, around 1730, John Hadley, an English astronomer, and Thomas Godfrey, an optician in the British colonies in America, both developed designs for an octant with a smaller graduated arc. The sextant later evolved from their work.

—Despite all the modern equipment on board, experienced mariners like Patrice Quesnel are still able to navigate using a sextant

The main reason why sextants are still in such demand is the rules that govern international navigation. These prescribe that every ship sailing the seas should be able to find its way without reference to a satellite. A magnetic compass and sextant are therefore essential equipment on board. For yachting enthusiasts worth their salt, a sextant from the house of Cassens & Plaths probably the instrument of choice. With them in mind, Cassens & Plath used to exhibit at all the main yachting fairs, though most sales nowadays take place over the Internet. The manufacturer has clear evidence that the instruments are in frequent personal use: sextants bearing the marks of wind and salt water regularly come in for repair.

Obtaining accurate bearings with a sextant is largely an acquired knack, the fruit of practice, but all this would be in vain if the instrument itself were not absolutely precise. This can only be achieved through fine mechanical craftsmanship. At Cassens & Plath, metallic whirring, squeaking and banging noises emerge from the work- shop all day long. For security reasons, the factory is sealed off from the outside world, almost like hallowed ground. Even the inspectors from Germanische Lloyd and other certifying bodies are only permitted to see the finished instruments. The body of a Cassens & Plath sextant consists of a brass casting. The apertures in its structure are emblematic of the company’s work and instantly identify it to specialists as a quality product from Bremerhaven. But a sextant’s quality does not depend on optics alone. Material has its part to play, too. Aluminium would be cheaper, but less durable, because it has to be coated and is therefore more prone to wear. Thus it would not meet the high standard, which the traditional company has set itself.

The blank casting first needs to rest. It is then deburred, polished and hollowed out. Cassens & Plath assemble an average of two sextants daily. Once the impressive instrument, with such a distinguished history, is finally housed snugly in its veneered mahogany box, complete with its certificate, the future owner can rest assured that everything has been completed to the greatest possible perfection. Cassens & Plath prides itself on holding all the certifications for its instruments worldwide, and the international licensing bodies regularly check standards. If the tiniest detail of a sextant or a manufacturing process is modified, a fresh application for the quality seals must be submitted.

But that is not the only reason why traditionalist Cassens & Plath has not changed its product for decades. Long experience is the sextant maker’s trump card. This instrument, dating back to an earlier century, cannot easily be imitated or copied.

Today’s skippers can still benefit from a few handy innovations. Polarization filters or shaded glass, for example, regulate brightness and protect the eye. In the past, when no such protection was possible, many sea captains became blind in one eye.

For yachting enthusiasts worth their salt, a sextant from the house of Cassens & Plaths is probably the instrument of choice

Explore More Articles
IWC Oils
Time That Runs Like Clockwork

Depending on the stresses and strains to which they are exposed, around 50 points in the movement are treated with oils and greases developed especially for use in wristwatches.

Test Lab

At IWC Schaffhausen, new watch models are put through a gruelling test program involving up to 50 separate stages that include long-term immersion in warm salt water and being locked away in an environmental chamber. All this guarantees that they will be equipped for everyday use – and much more – when they finally reach their future owners.

Sound_check_engine_AMG_972x426
Sound Check

How the engineers at Mercedes AMG in Affalterbach, southern Germany, create the right engine sound.

HALF_WAY_TO_THE_MOON_Trucks_972x426
HALF WAY TO THE MOON

For the MERCEDES AMG PETRONAS Formula One™ Team, following the Grand Prix circus means transporting 30 tons of material in 10,000 individual parts and at least 60 employees to venues on five continents. Of course, they have to ensure that everything arrives there on time what calls for a system and improvisation in equal measure.

Grande Complication Dial Explained
Small World

Time moves the world. The IWC Portuguese Grande Complication is an understated, beautifully designed way of summarizing time as the motor of all change: a time machine that shows a tilted globe on the dial.

89800 Calibre Movement
Eternity in Digits

The IWC-manufactured 89800 caliber, which made its debut in 2009, redefined the digital date display. The triple-disc mechanism in the perpetual calendar features large-format displays for the date and month and, slightly more discreetly, the leap year cycle. All are ingeniously synchronized.

Top Secret

In a small town in central England, over 500 specialists spend their time developing and building silver arrows for the MERCEDES AMG PETRONAS Formula One™ Team. Almost every one of the 3,200 parts in each car is custom-made.

Ingenieur: the story of a legend

When the Ingenieur from Schaffhausen was launched in 1955 it created a storm. But its actual history goes back much further: to 1888.