Showing posts with label Copernicus. Show all posts
Showing posts with label Copernicus. Show all posts

Wednesday, March 25, 2026

The Clock in St. Mark's Square - Venice, Italy


Someday I hope you will all travel to Venice, Italy and see this clock. Built in the 1490's it is one of the most extraordinary in the world. And considering when it was built it is still a marvel of engineering and architecture. In 1998 it was cleaned and all the beauty of the facade was made visible again. Big difference from what it looked like in the 1970's when I saw it.

I was watching an old Italian film called "The Assassins" from 1952 in which the clock is shown. Piqued my memory. I do not recommend the film, only the clock, located in St. Mark's Square in Venice.

There is a great Wikipedia article about this clock and the family who maintained it from 1497 until 1998. 500 years. One family, one clock. They actually lived in the tower! There are 2 different links, both worth reading.

To me one of the most extraordinary aspects of the clock is the astronomical feature, which involves 5 planets and the Sun. This was 40 years before Copernicus proved that the Earth revolved around the Sun. And 100 years before the Catholic Church banned Copernicus! 😂

And here are the 2 "Moors" who actually strike the hours. They are located several stories above the actual clock face.


Also of interest is the fact that this extraordinary clock also pre dated the 1707 Scilly Island disaster, in which a British fleet was lost due to the need for understanding the principles of "arc to time". 

In 1714 Parliment passed the Longitude Act, which offered a big reward for anyone who could solve the problem. Still, it took another 57 years for a man named John Harrison to accomplish this feat. Without his accomplishment it was really an educated guess as to where your ship actually was. Even today's sophisticated Navigation Satellites owe a huge debt to Harrison's H4 timepiece.

Friday, February 28, 2014

February - The Short Month

I posted this article 2 years ago today. It is one of the more popular posts which I have written. The history of the calendar has always fascinated me; from the early religious lunar calendars to the more modern solar calculations and even the atomic clock; it’s all of interest to me. Time itself may be infinite; but you and I are here for a finite period, which will come to an end soon enough. Maybe that’s why I’m so concerned about how they keep score; I wouldn’t want to miss a single minute!

Imagine having your summer vacation in January, or Christmas in June. Seems unlikely, doesn’t it? But that’s exactly where we would be at today if Caesar had not adopted the changes to the “Julian” calendar when he added one day every fourth year to keep everything in order. Of course, we know it as leap year, and it is an accepted part of living, engendering such witticisms as, “If you’re born on February 29th then you don’t get to vote until you’re 72 years old!” Or, “If you marry on February 29th then you only have to buy the wife a gift every 4th year.” Right; you try it, and let me know how that works out for you.

I have always been fascinated by numbers, even when failing math in grammar school.(I was fascinated at how low my grades were.) Still later, while working as a grocery clerk, before the advent of the modern day cash register, I was further enamored of the precision of numbers in general. And, still later, as a Quartermaster in the Navy, and then as a qualified 3rd Mate aboard oil tankers, the absolute nature of the stars in their movements, hooked me on math forever. In that spirit I offer the following, and accepted, mathematical reasons for the need of a leap year.

In 46 BC, Julius Caesar was faced with the problem that the Roman calendar then in use had slipped 81 days. This was especially noticeable at the spring equinox, which was an agricultural benchmark affecting the planting of crops. Something needed to be done to correct the error. Caesar simply added 81 days to the calendar, and instituted the leap year, bringing all things back to their proper order; for a time.

The Julian calendar, which is the one in use from 46 BC until 1582 AD, was based upon 365.25 days for one journey around the sun. Now, this was pretty good shooting for 46 BC, but by the 16th Century advances in science, and navigation, had revealed the actual length of time to orbit the sun as being a bit shorter; 365.2422 days, which meant that we were now out of whack by 10 days, which was fouling up the date on which to observe Easter. In preparation for Easter of 1582, Pope Gregory XIII deleted 10 days for that year, which reset the clock, so to speak. That became known as the Gregorian calendar, which is what we still use today.

As time has gone by, even the Gregorian calendar has come up for correction. George Washington, the father of our country, was actually born on the 11th of February in 1732. His birthday was advanced by 11 days in 1752 when the colonies switched from the Julian calendar to the Gregorian calendar. I have never really been sure of why the colonies were using the older Julian calendar, so I will have to look into that. But poor George Washington, he seems destined to never have a permanent birthday, as we now celebrate his special day as a three day weekend, or President's Day, which gives him a “leap” in his birthday every year, rather than one in every four.

There are many different calendars in use around the world, each with its own version of Leap Year. My own religion, Judaism, makes use of the older Lunar calendar which requires a correction of almost 20 days, or so, making it a 13 month year. That month is named Adar I, or, the "lucky" month. It is neatly slipped in between the months of Shevat and Adar, giving the leap year a total of 385 days. The Jewish Leap Year is also known as the "Pregnant" year; "Shanah Me'uberet" in Hebrew; as it bulges with extra days. These leap years are distributed 7 times over a 19 year period, and occur during the 3rd, 6th, 8th, 11th, 14th, 17th, and 19th years of the cycle. This is known as the Metonic cycle and marks the moons return to the exact place, at the same longitude, with the same constellation in the sky. Moreover this occurs at the time when the moon is in the exact same phase as it was at the beginning of the cycle.

I hope this has been of some help to you in understanding the calendar we use today; especially how it relates to the lunar, religious cycles which govern most of our religious holidays. It’s a fascinating topic and this small post of mine merely touches upon the proverbial tip of the iceberg.