In 1934, Lewis Mumford, one of the forefathers of the history of technology as a discipline, praised the invention of the clock in his classic Technics and Civilization: The clock, not the steam-engine, is the key machine of the modern industrial age. ... Even today no other machine is so ubiquitous.(1)
Yet in the Middle Ages, clocks were in fact not ubiquitous. Mechanical clocks only came into existence in the Europe in the 1300s. Most medieval clocks were large public display pieces, not personal trinkets. These large, expensive, complicated artistic pieces found their homes in cathedrals and town squares.
Many of the earliest clocks did not have faces. The mechanisms were created in order to ring bells on the hour, not to show an exact time of day. You can still see an example of this kind of clock mechanism in the cathedral of Salisbury, England. Click to see a video of the clock in action.
Using the moving mechanisms, figures could be added to strike the hour. In Italy, the first clock with little mechanical figures was set up in a tower at Orvieto in 1351. The figure of a man strikes a large bell every hour. A 1354 clock from Strasbourg Cathedral had a mechanical rooster that flapped its wings and crowed on the hour. These clocks with figures reveal how important display was to the clock. The clock was as much a showpiece as a technology for timekeeping.
In fact, the minute hand of the clock was only introduced in 1577. Medieval people thought of time as something much more general and flowing than we do today; precision in time was not particularly valued. This gives us some insight into how relaxed people were in the Middle Ages about the time of day.
The Prague astronomical clock shown on the left above is one example of such a showpiece. The astronomical dial likely dates from 1410 and the calendar dial from 1490. The ornate stone sculptures likely date from the end of the 15th century. The clock then was much more than just a dial. It was an entire artistic wall piece.
So what was the purpose of these clocks for viewers?
Clearly, the majority of clocks were showpieces of artistic skill and wealth. It was important for the civil leadership to display their right-to-rule through visible signs -- and clocks could be one of these. But the emphasis on astronomical clocks also reveals a preoccupation with "scientific" knowledge, technological skill and God's creation. Although clocks were often in public spaces, they still retained some of the sacred character of time we saw in churches' calendar images. Seeing all of the moving parts, automatons, and images of the heavens certainly invoked a sense of wonder on medieval viewers. And not much has changed -- the modern crowds around Prague's astronomical clock testify to that.
(1) Lewis Mumford, Technics and Civilization (New York: Harcourt Brace & World, [1934] 1963), 14.