Most IT people think that the digital age started with the invention of semiconductors, very large scale integration and programming languages. However, our computers are still based on digital clocks which have been invented and used centuries ago. IT technology has its roots in the clock industry. Many of the early IT pioneers had a background in mechanical design especially clock design. The Babbage calculator of 1822 used typical components of the tower clocks of its time.
The digitization allowed to build very accurate clocks hand made by blacksmiths with simple tools and techniques. The very old tower clocks are really fascinating. Today you will find tower clocks mostly in private collections and museums e.g. at the German Museum für Zeit – Pfälzisches Turmuhrenmuseum in Rockenhausen, Germany, where you can find clocks made by blacksmiths in the 18th century as well as a highly sophisticated Big Ben model.
Here you also can see how clocks became smaller much like modern IT equipment. But there always was a digital clock!
Tower clocks in museums are nice but my real champion is the clock tower clock in the little town of Katzenbach (close to Rockenhausen) which was running and is still running for 250 years.
The program is rather simple with inner and outer loops. It is using two bells for wireless communication with the customers. The little bell rings every 15 minutes, the large bell indicates the hours. At 11 o’clock the a big lunch time ringing starts. Thus the farmers could head for home and have lunch at 12 o’clock. I don’t think that there is any modern program around which will be used in 250 years from now and does not have any programming errors!
The blacksmith, who made this clock, proudly signed his work. (By chance it was one of my ancestors.) Most modern programmers would not support this idea of signing their programs with their names. I know only a story of Steve Jobs who asked the developers in good old times to sign off their work. I don’t think they still do this today.