Scientist of the Day - The Charles Bridge
The Charles Bridge, with Old Town to the right (east), detail of panorama of Prague, etching by Johannes Wechter, after Philip van den Bossche, published by Aegidius Sadeler II, 1606, Metropolitan Museum of Art (metmuseum.org)
According to legend, the first stone of the Charles Bridge in Prague was laid by Emperor Charles IV on July 9, 1357, at 5:31 in the morning. The time and date were supposedly chosen by the numerologically sensitive Charles because, when written in the form: year, day, month, hour, minute, it forms an interesting sequence: 1357/9/7/5/31 – a numerical bridge, one might say. Charles would have been hard pressed in 1357 to find a clock that would give him the time to the second, or even to the minute. But it is a nice story, and it gives us the opportunity to wish Happy Birthday to an object that has lived out its extended life – 668 years and counting – without flesh and blood (although plenty of that has been spilled on its stony flanks).
A modern view of the Charles Bridge, looking toward Old Town and the Old Town gate (Wikimedia commons)
In addition to being very old, the Charles Bridge is rich in historical associations, a few of them scientific; it may indeed be the most storied bridge in the world. The bridge was designed by Peter Parler, who was only 23 years old when he was handed this project, but already a masonic veteran, having worked for his father since he was a toddler. I thought about making Parler the subject of this post, but I really wanted to tell the story of the bridge, which has had quite a life of its own. We will come back to Parler someday, since he also constructed St. Vitus Cathedral, which you can see looming above the bridge in several of the views, especially our fourth image.
Statue of St. John of Nepomuk, Charles Bridge, Prague, recent photograph (Wikimedia commons)
The Charles Bridge has sixteen stone arches, each one protected by ice-deflecting abutments, and is over 32 feet wide, which means one could march entire armies across it, and this was often done. It spans the Vltava River (which used to be known in the west as the Moldau), and connects the section of Prague known as Old Town with the sprawling Castle complex. The dark Gothic gate in our second image marks the entrance to Old Town. The bridge is now famous for its statues, 30 of them, that line the two sides, but they were a later addition, erected mostly after 1650, and include no scientists at all, which I find mildly distressing, given that some rather prestigious astronomers and alchemists walked upon its cobblestones. It might have helped if some of them had been thrown off the bridge, as was John of Nepomuk, martyred this way in 1393 and then rewarded with an often-photographed statue (third image).
Another modern view of Charles Bridge, with St. Vitus Cathedral and Prague Castle on the hill at left.
In 1606, Aegidius Sadeler II published a panoramic view of Prague that situated the bridge within the civic context of Prague (fifth image, below). Our opening image is a detail from this panorama. You can't miss the bridge, right in the center – note that it was the only bridge over the Vltava River at the time. Old Town is to the right, and Prague Castle and St. Vitus Cathedral are to the left. In Old Town, the dominant feature is a church facing the Old Town Square; this is the Church of Our Lady before Týn, which you can identify because it has two spires, each with 8 smaller spires upon it. It is just to the right of center in our first image. And here we can make our first science connection. Johannes Kepler, the Imperial Astronomer for Rudolph II, worked at the Castle, but when he wanted to worship, he had to leave the Castle, because Kepler was a Lutheran, and there were no Lutheran churches in the Catholic castle domain. So Kepler would walk across the Charles Bridge to Our Lady before Týn, a Hussite church that also held Lutheran services. Kepler's predecessor, Tycho Brahe, lived at Benatky, outside Prague, but when he was in Prague, before his death in 1601, he would have made the same trek, since he was a Lutheran like Kepler. Tycho, in fact, is buried in the Church of Our Lady before Týn, and since Tycho was a nobleman, many of his fellow nobles would have crossed the bridge to attend his funeral. You can see the wall plaque above his tomb in one of our posts on Brahe.
The Charles Bridge, entire panorama of Prague, with Old Town to the right and the Castle and Cathedral to the left, etching by Johannes Wechter, after Philip van den Bossche, published by Aegidius Sadeler II, 1606, Metropolitan Museum of Art (metmuseum.org)
Seventeen years after Tycho died, and 6 years after Kepler left Prague for Linz, the Thirty-Years War broke out, when Bohemian Protestants rebelled against a new Emperor, Ferdinand II, who promised to make Roman Catholicism the religion of the land. At the Battle of White Mountain in 1620, the Protestant armies, led by Frederick V, King of Bohemia, were defeated by Imperial forces, and Frederick fled with the remains of his army across Charles Bridge. There is a beautiful wood carving in St. Vitus Cathedral that commemorates the flight of Frederick and provides a splendid view of the bridge (sixth image).
The Charles Bridge in a woodcarving by Gaspar Bechteler, 17th century, in St. Vitus Cathedral, Prague, photograph (bobandnellasworld.com)
Aside from regularly traipsing back and forth across the bridge, Kepler credited it with a small role in the composition of one of his books. In 1611, Kepler published a small pamphlet called Strena seu de nive sexangula,which translates as A New Year's Gift: The Six-Sided Snowflake (we have this book in our History of Science Collection). The book is about more than snowflakes; it is a general introduction to the problem of packing polygons. But in the preface, when he is explaining to the dedicatee that he was too poor to buy a new year's present and so was writing this book, Kepler comments that he got the idea for his Strena when he was walking across the Charles Bridge and noticed two snowflakes on his coat, marveling that both were six-sided. The book was launched right then, and the Charles Bridge gets the credit.
A wonderful view of the Charles Bridge under leaden skies, looking toward Old Town, modern photograph, uncredited (thenextcrossing.com)
We conclude with a beautiful uncredited photo (seventh image), showing the Charles Bridge beneath somber skies, that I found on a website called The Next Crossing. There are many other fine photos of the bridge on his site. You can even check out, if you wish, a Google Doodle commemorating the birthday (this day) of the Charles Bridge, posted on July 9, 2017.
William B. Ashworth, Jr., Consultant for the History of Science, Linda Hall Library and Associate Professor emeritus, Department of History, University of Missouri-Kansas City. Comments or corrections are welcome; please direct to ashworthw@umkc.edu.
