“A Pioneer in the Service of Watchmaking”
Born in The Hague, Christiaan Huygens lived from 1629 to 1695. This Baroque polymath was far ahead of his time with many of his inventions. He was active in a remarkable number of fields and demonstrated his brilliant versatility in every one of them. The development of the pendulum clock and the improvement of timekeeping accuracy stand out as a milestone in his life's work.
The Foundation of Modern Luxury Watches
He improved microscopes, designed combustion engines, built telescopes, and recognized the talent of the painter Rembrandt, whom he recommended to the Prince of Orange: Christiaan Huygens was a polymath who distinguished himself scientifically in many of the fields of his day and was driven by a boundless inventive spirit. He studied mathematics and law, wanted to know how lenses were ground, and built telescopes for observing the stars. His best-known discovery, which bears his name, is Huygens' principle on the diffraction and refraction of light. He studied the suspension of carriages and the silting of coastlines, made a drawing of the Orion Nebula, and improved the magic lantern and the pendulum clock: his improvement is still used today in the manufacture of mechanical luxury watches.
The Life of a Polymath Who Is Almost Forgotten Today
Born in The Hague on April 14, 1629, the son of a high-ranking diplomat, poet, and secretary to the duke, Christiaan Huygens received the finest education of his time. Until he entered the University of Leiden in 1645, where he studied mathematics and law, Huygens was taught by private tutors. In the 1650s, together with his brother Constantijn and Baruch de Spinoza – who not only philosophized but also ground lenses – he improved the simple telescope with which Galileo had once made his discoveries. They developed lenses that allowed for higher resolution. This enabled Huygens to observe the ring of Saturn already described by Galileo, and he discovered a large moon orbiting Saturn, which he named Titan. Because his astronomical observations and research required more precise timekeeping than the clocks of the day could provide, he turned to horology. A good fifty years before him, Galileo had already noticed the harmonic motion of the pendulum, which was later examined and described in greater detail by Newton in the Principia. Until then, time had been displayed by wheel clocks driven by weights and fitted with a striking mechanism, much like today's church tower clocks still are. Huygens added a pendulum to these movements; with its regular motion, it could control the escapement and ensured considerably better accuracy. Huygens presented the first pendulum clock in 1657, and in 1673 he described its exact construction and mode of operation in the Horologium Oscillatorium sive de motu pendulorum. He applied for a patent on his pendulum clock. Its accuracy, with a maximum deviation of ten seconds per day, was so outstanding that it took one hundred years before this precision could be surpassed. Shortly afterward, he added a balance wheel with a hairspring and in this way designed a pocket watch that could be regarded as a true luxury watch at the time. Christiaan Huygens lived as quietly and withdrawn a life as he possibly could. For a while he lived in Paris, but as a Protestant, life in Catholic France was not easy for him. In 1682 he returned to The Hague, where he died on June 8, 1695.
Tracking Time with a Pendulum
Almost every child is fascinated watching a plumb bob swing back and forth for a while before finally coming to rest and indicating the vertical. Christiaan Huygens was probably just as captivated by the regularity of the pendulum's swing when he invented his automatic pendulum clock. Through the oscillation of the pendulum, it regulated the rate of the escapement and thus of the entire clock. Via a feedback mechanism, the wound movement repeatedly gave the pendulum small impulses that kept it from stopping and made it swing on and on. Although a tiny amount of energy is constantly lost to friction, the pendulum receives it back from the movement. With the pendulum clock, he created a timekeeper so accurate that, for the first time, the time of day could be determined in minutes and seconds. From then on, appointments and activities could be fitted into an ever tighter schedule. The need for continuous timekeeping was especially high in merchants' counting houses; for them, pendulum clocks were not luxury items but served to optimize work and profit.
Pendulum Clocks on the High Seas
When ships were out on the high seas, the nautical instruments of the time could not determine their position reliably. If a ship sails west, for example, it crosses the meridians of longitude. 60 degrees of longitude mean that the sun reaches its highest point at noon four hours later. The same delay also applies to the constellations at night. Huygens hoped the pendulum clock would be accurate enough to determine these differences reliably and thus establish the ship's position. In the process, it was found that the accuracy of the pendulum clock depended crucially on the length of the pendulum: while the clocks ran with high accuracy in Paris or London, they deviated near the equator. Shortening the pendulum by a few millimeters helped here. For Isaac Newton, this later became an indication that the Earth's varying gravitational pull also affected the pendulum and the accuracy of the clocks, and in the process he discovered that the Earth was not a perfect sphere but flattened at the poles.
The Balance Wheel Becomes the Racing Heart of a New Era
Christiaan Huygens had recognized that measuring longitude at sea required a timepiece far less sensitive to the rolling of ships than his pendulum clock could be. He developed a spiral spring that oscillates around its center position and served as a new regulating organ for mechanical timepieces. The balance is a small oscillating wheel driven by a coiled spring – a miniature pendulum, so to speak. This small component became the heart of the newly developed mechanical pocket watches. Shortly before the beginning of the 18th century, privately worn pocket watches rose to become the first luxury watches, regarded as proof of upper-middle-class standing. Yet the new generation of watches was not merely an expression of prestige. The more precisely watches displayed the passage of time, the more they also influenced how people perceived time. Once technology made it possible to show the time more accurately, clocks admonished the tardy, people began talking about punctuality for the first time, and time clocks were introduced to record working hours.
Luxury Watches Were Made in Workshops Almost in Series
After Christiaan Huygens developed the pendulum clock and thereby decisively improved the accuracy of timekeepers, luxury watches were being produced almost in series in many larger workshops in Paris and London by the early 18th century. The great art of watchmaking began with Christiaan Huygens' developments and was later refined and carried forward by many other brilliant watchmakers. One of the phenomena Huygens observed, the spontaneous synchronization of the double pendulum clock, was in fact only recently explained by scientists. Originally developed for use at sea, such a double pendulum clock was reconstructed by the scientists, who observed its oscillations using laser technology. They analyzed the data with computers and found that Huygens' double pendulum clock is a special case in which the mass of each pendulum stands in a very specific ratio to the total mass of the clock. Since each pendulum not only absorbs energy with every swing but also transfers it to the suspension, part of that energy is passed to the other pendulum, and after a while both pendulums synchronize.
