From shadow measurement to the clock: the history of watchmaking!

Every man has always filled his life with activities that, produced and exhausted at different times of the day, regulate his very existence. The implementation of these therefore marks the rhythm, almost like a continuous flow in which action and rest, day and night, light and darkness alternate, and the perception we have of time. This yearning to define time precisely is perhaps inherent within us, an exorcising justification for the flow of life and its inevitable decline, an indicator of an intelligent and, above all, conscious existence. Perhaps moved by these considerations, the Babylonians intuited, about 5000 years ago, that time could be measured by calculating the interval between one full moon and the next. Having established that this was accomplished in about 30 days and that every 12 full moon cycles the light emitted by our satellite hit a graduated indicator in the same point, they deduced that a solar year could therefore count 360 days (12 months of 30 days). This number was, among other things, rich in symbolism, related to their geometric knowledge: it was equivalent to the sum of the degrees of a circumference, divisible into sectors - like the months - and above all resulting from the multiplication of the sacred number 12, present in myth and religion (just think of the 12 labors of Hercules, the 12 apostles...) and which, with the Babylonians, became the cornerstone of the solar day, divided into two periods of 12 hours (day and night). Thousands of kilometers further north, at Stonehenge, in 2000 BC, a solar temple had been built that indicated in an incredibly precise way, with its enormous monoliths, the equinoxes, solstices and alignment of celestial bodies. The Egyptians instead relied on the shadow cast by the pyramids, measuring its length at various times of the year (tempus fugit, sicut umbra), for astronomical calculations of considerable complexity. Yet all these discoveries remained the prerogative of a select few. It was precisely the descendants of the pharaohs who felt the need for measurements of "personal" time, in addition to "general" time. This led to the development of gnomons, sundials and water clocks (hourglasses), progressively equipped with increasingly sophisticated and complex devices and automatons. The most famous is perhaps that of the Greek Ctesibius (3rd century BC), who created a clock equipped with a float, which reported the hours on a circular dial, following the progressive emptying of the container with containing the liquid.
The Chinese perfected the technique of calculating the passage of time based on the consumption of a material: here are the oil lamps and candles calibrated to burn out within defined periods. Indeed, by developing the knowledge of the convective properties of lenses, they were able to design a timepiece powered by fuses ignited by lenses exposed to the sun, which activated cannons or explosive charges.

Obelisks, pyramids, menhirs, or simply poles, sticks, mountains were therefore the first timepieces, which allowed the passage of the hours to be calculated through the length of the shadow they cast; when this shadow was measured on a graduated dial, they took the name of sundials. This clock (“hora lego” or, according to another etymology, “horologium”, which originates from water instruments and although in various dialects and languages ​​- horloge, reloj, orloge, oriolo... - will continue to indicate, from the 13th century, also the mechanical clock) spread especially in countries with higher solar exposure, such as the Arab ones, which brought it to high levels of precision and reliability. Here, on a similar concept, the astrolabe also developed, an instrument that allowed the recognition of certain stars and, based on their position, to determine the time, both day and night. It remained a fundamental accessory of navigators, such as Columbus and Vespucci, until the advent of modern clockmaking (which solved the problem of calculating longitude). The hourglass, on the other hand, especially in the more practical sand version (clepsamia), rather than liquid, was enormously widespread throughout the ancient world, measuring from the times of Athenian lawyers' speeches to the times of soldiers' guard shifts and remained in fashion until the advent of the first mechanical clocks, many centuries later.

The first known completely mechanical clock is that of Henri de Vic, a German, called to France by Charles V, and intended to decorate the Palais de Justice in Paris. Built entirely of iron, it was moved by a weight of 225 kg and is the first example of a mechanism in which the three fundamental parts of a timepiece can be distinguished: motor, gear train and regulator. The first provides the force, the second the transmission of the same to the indicator needles, the third the more or less constant modulation of the transmitted energy. This last component is the one that has most encouraged human ingenuity, in the search for a gradual, but above all precise, distribution of the force transmitted by the weights first and then by the spring charge.

The planetary clock by Giovanni Dondi, from Padua, dates back to 1344. He even obtained the honour of being called Dondi Dell'Orologio in consideration of his genius applied to the construction of this artifact.
In the Middle Ages, the spread of tower clocks in the churches of the major cities revolutionized life and society: the ringing of bells, operated by the sacristan at the agreed hours, marked the phases of work and rest of the farmers, called to prayer, regulated the rhythms of commercial activities. This diffusion stimulated the creativity of artisan blacksmiths, who developed the first domestic clocks, first equipped with weights and later operated with spring mechanisms. Towards the middle of the 15th century, in an increasingly shorter temporal succession, increasingly more sophisticated escapements were developed, aimed at miniaturizing the dimensions of the mechanisms and ensuring their precision. Cities such as Nuremberg and Augsburg developed, between the 15th and 17th centuries, their economies thanks to the clock and the synergies of clockmakers, goldsmiths, bronzesmiths, brasssmiths, engravers and enamellers who came together in guilds dedicated to its construction. The first pocket watches attributable to the clockmaker Peter Henlein around 1500 are called Nuremberg eggs, based on their awkward shapes (or more probably following a translation error). In 1525 in Prague, the clockmaker Jacob Zech invented the fusee, a device that guaranteed regularity of delivery to the action of the mainspring. The Thirty Years' War (1618-1648) however emptied the main German cities of their highly skilled clockmakers (the vast majority of whom were Protestants) who emigrated mainly to Paris (where the clockmakers' guild had existed since 1544), where highly specialized workshops flourished. The subsequent revocation of the Edict of Nantes meant that these refugees were also persecuted in France and found asylum in Switzerland and England which became the main centers of clockmaking production for centuries to come. At the beginning of the 18th century London was the world capital of watchmaking (the London guild was established in 1632). Significant improvements in achieving the precision of clocks were the application of the pendulum, implemented by Christian Huygens, in 1657 (studying the physical laws of Galileo Galilei), the spiral spring of the balance wheel, invented around 1660 by Robert Hooke, the cylinder escapement of Georges Graham, which remained in use in pocket watches until the 19th century, and the anchor escapement, invented in 1765 by the Englishman Thomas Mudge. This quest for perfection had real and economic implications: the problem of calculating longitude exactly, for example, had occupied the most talented mathematicians and astronomers for centuries.
While latitude was easily detectable by observing the Sun and the stars, it was much more difficult to establish the position of a ship with respect to east and west. Naval disasters caused by miscalculations cost the various States unimaginable figures, to the point that the Monarchs offered significant prizes to whoever managed to build a clock capable of being precise even during navigation.

We have learned that in the 18th century the so-called “personal watch” or “pocket watch” developed forcefully. There is an anecdote according to which the tailors of the 17th century had to invent suspenders to allow gentlemen to wear their watches, which were certainly bulky and heavy (see the so-called Nuremberg Egg): this uncomfortable feature was, fortunately, eliminated thanks to the ingenuity of Jean Antoine Lepine.

French, he reduced modern watches to a flattened cylindrical shape, eliminating the so-called “conoid” system with verge escapement, replacing it with a series of bridges that supported the various pins of the wheelwork, inside which he positioned the balance wheel and the mainspring barrel. At the same time in England, for the first time, watches were made with ruby ​​(and sometimes diamond) bearings in which the axles turned with less friction, offering greater precision. However, it was Abraham-Louis Breguet, a Swiss transplanted to France, who gave the decisive impulse to the evolution of the pocket watch.

He adopted, in his production, above all the cylinder escapement of George Graham, bringing notable improvements in terms of duration and precision. He developed, among other things, a spiral spring with a particular bend of the external coil, to which he gave his name, which also allowed a notable evolution of the lever escapement invented by George Clements. Breguet had already become so famous at the end of the 18th century that he had to immediately remedy the counterfeiting of his watches, by adding hidden or camouflaged signatures in the enamels of the dials. Among his clients were Bonaparte and Josephine, the Tsar of Russia and Louis XVIII. Subsequently, the Englishman Thomas Mudge, John Arnold, John Harrison and others made further technological progress, especially by developing and improving the lever escapement, which, in addition to making watches more precise, helped to strengthen England's position as the main centre of watchmaking production in Europe. The industrial revolution radically changed the way watches were produced: in Switzerland, workshops flourished that produced individual parts of movements, which were then assembled, by the most famous and structured workshops, into good quality, low-cost watches. Perhaps the first to understand the commercial possibilities of the inexpensive watch was Roskopf: his production reached its peak in the mid-19th century. The enormous competition that had developed among English watchmakers had meanwhile made it necessary to search for new markets: many moved to America where, in a short time, various independent schools of style and technique flourished, such as those of Philadelphia, Boston, New York. The Willard brothers are an example of the very high technological level achieved by American watchmakers already at the beginning of the 19th century. Later, around 1850, factories such as Waltham, Elgin and Illinois appeared on the American market: their watches were certainly inferior technically to the Swiss ones, but they had such a low cost that they covered the already large American market in a very short time.