As a digression from clock graphics, which are simply animated graphics resulting from a combination of many types of coding, it is interesting to look at some of the mechanical aspects of real clocks and in particular at the pendulum that for almost three centuries was an important component of clocks that contributed to their ability to maintain the correct time.
Galileo Galilei (1564 – 1642) was an Italian astronomer, mathematician, physicist, philosopher and professor. He is perhaps better known for his defence of the theory of heliocentrism, the astronomical model, which puts the sun at the centre of our planetary system. It was developed by the Polish mathematician and astronomer Nicolaus Copernicus (1473 – 1543) and published in 1543. After years of debate this resulted in Galileo being called before the Italian Inquisition. Arriving in 1633 and after more debates, he was finally found “vehemently suspect of heresy” and was sentenced to formal imprisonment at the pleasure of the Inquisition. On the following day, this was commuted to house arrest, under which he remained for the rest of his life.
The story of the pendulum begins much earlier in 1588, after watching a suspended lamp swing back and forth in the cathedral of Pisa, when Galileo was still a student there. He had discovered that the period of swing of a pendulum is independent of its amplitude (the arc of the swing). The swing is isochronous, i.e. is equal or uniform in time. In 1602 he explained this isochronism of long pendulums in a letter to a friend. A pendulum could be used for timing pulses or acting as a metronome for students of music: its swings measured out equal time intervals. Could the device also be used to improve clocks?
Many years later his devoted assistant Vincenzo Viviani (1622-1703) relates in an article written 17 years after the death of Galileo and translated from the Italian by Stillman Drake: One day in 1641, while I was living with him at his villa in Arcetri, I remember that the idea occurred to him that the pendulum could be adapted to clocks with weights or springs, serving in place of the usual tempo, he hoping that the very even and natural motions of the pendulum would correct all the defects in the art of clocks. But because his being deprived of sight prevented his making drawings and models to the desired effect, and his son Vincenzio coming one day from Florence to Arcetri, Galileo told him his idea and several discussions followed. Finally they decided on the scheme shown in the accompanying drawing shown above, to be put in practice to learn the fact of those difficulties in machines, which are usually not foreseen in simple theorizing. Vincenzo Viviani was probably motivated to write this after reading the publication of a paper by Huygens about his making of the pendulum clock. Galileo had the idea for a pendulum clock, which was partly constructed by his son in 1649, but he also died before the pendulum clock was completed.
Christiaan Huygens (1629 – 1695) was the first to make a working pendulum clock in 1656. The application of the pendulum to clock timekeeping during the scientific revolution of the 17th century was the most important advance in the history of time measurement and gave accuracy to stationary clocks until the early part of the 20th century.
After Christiaan Huygens designed the first successful pendulum clock in 1656, he worked with Coster, an experienced clockmaker, to apply his new invention to commercial use. The clock above was made c 1657 by Salomon Coster (1620 – 1659), a clockmaker in the the Hague, Netherlands and is one of the earliest pendulum clocks ever made. In 1657 Huygens had the patent protecting his invention assigned to Coster, but sadly Coster died suddenly in 1659 after producing only a few pendulum clocks. John Fromanteel was the son of a London clockmaker, Ahasuerus Fromanteel (1607 – 1693), and had gone to work for Coster. A contract had been signed on 3 September 1657 between Salomon Coster and John Fromanteel, which allowed Fromanteel to continue making the clocks. John and Ahasuerus implemented the new, more accurate pendulum technology and became the first makers of pendulum clocks in England.