While modern society takes for granted the free availability of timekeepers around us, for Jefferson and the American founders, time was an expensive, but critical and luxurious tool for managing their estates and affairs. Typically, Jefferson and the American founders had to source their watches and clocks in Europe and go through great lengths to obtain them.


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President Jefferson’s Napoleon Clock. Louis Moinet


President Jefferson was not only an admirer of haute horology, he was also a patron to highly-skilled watchmakers of the era. One of the most prominent timekeepers he commissioned outside of America was a Napoleon clock from renowned watchmaker Louis Moinet. He was among the high-profile individuals eligible to qualify as patron to the French watchmaker. Among those clients were Napoleon Bonaparte, King George IV, President James Monroe, Tsar Alexander I of Russia, King Joachim Murat of Naples, and Queen Maria Amalia of Naples and Sicily. Louis Moinet’s legacy in watchmaking is most notably distinguished by his invention of the chronograph and close relationship with Abraham-Louis Breguet. 


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Thomas Jefferson’s astronomical clock made by Thomas Voigt. credit:


A keen observer of celestial phenomena, Thomas Jefferson had been determined to star gaze during momentous astronomical occurrences. Stemming from a lunar eclipse in 1778, he had dreamed of one day owning an astronomical clock. However, The Revolutionary War delayed his commissioned work to American astronomer, clockmaker and renaissance man, David Rittenhouse. 

More that three decades later, Jefferson would finally see his dream clock come to fruition when he was introduced to Thomas Voigt. Voigt’s father, Henry, was a celebrated clockmaker during the American Revolution. His lineage garnered the attention of Jefferson who would go on to appeal to the Philadelphian watchmaker’s expertise. Incredibly, the clock was commissioned and completed within a year. Although, the former president would have to wait for the delivery to be undertaken in 1815 due to logistics issues caused by The War of 1812.


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Interior of Thomas Voigt’s Astronomical Case Clock. credit: The Thomas Jefferson Foundation (Wikipedia)



Obelisk Clock made by Louis Chantrot (1791)


Perhaps the most personal of Jefferson’s timepieces was his obelisk clock located at the edge of his bed. The clock was created shortly after he had moved back to the United States replacing another clock which had been stolen from his home in Paris. Jefferson’s love for culture included music, literature and architecture. He sketched a prototype which incorporated a clock chained to a set of obelisks and sent it to his personal secretary that remained in France. 

Records indicate that Jefferson’s correspondence led to the French clockmaker Louis Chantrot creating the timepiece. Louis Chantrot wrote back to inform Jefferson that the specifications would not be exact, yet he encouraged that he would be extremely satisfied with the final result. Adorned with black marble and gilded bronze, the clock is lavishly designed featuring an exposed dial, intricate hands and beaded texture throughout the bronze surfaces. For over 30 years the obelisk clock would be admired at his bedside. With this in mind, it is not surprising in the least to learn it was among Jefferson’s most sentimental clocks.  


Thomas Jeffersons initial design sketch of the obelisk clock which would go on to be created by Louis Chantrot. 1

Thomas Jefferson’s initial design sketch of the obelisk clock which would go on to be created by Louis Chantrot. credit:


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The Great Clock made by Peter Spruck (1792) | credit:


One of the most fantastic horological creations to come out of the United States is undoubtedly Thomas Jefferson’s Great Clock. Housed on both the interior and exterior of the Monticello plantation home, it is a remarkable testament to late 18th century innovation. Created in 1792, the unrivaled technology was a collaborative work between Peter Spruck and the then US Secretary of State. Jefferson’s influence was by way of design, whereas Spruck constructed the complicated timepiece that remains fully functional to this day. 


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The Great Clock is powered by a weight-driven pendulum. Its functional elements expand throughout the Entrance Hall into the home’s basement by way of a weight driven apparatus. Because Jefferson’s design was originally intended for his Philadelphia residence with a much higher ceiling, the calendar system could only accommodate the weekdays, leaving a problem accounting for both Saturday and Sunday. Rather than abandoning the date complication, he decided to carve a hole into the floor allowing for the weights to descend into the basement.



The passing of each hour was recognized by a striking mechanism that can be heard across the entire plantation. The practice of signifying the time through sound dates back to the earliest mechanical timepieces. Within villages across Europe bell towers would inform the working class of the current time. Interestingly, this lends insight to the reason we use the term “clock”, as it derives from the translation of “bell” within various languages. Being that Jefferson was well studied on societal practices throughout European history, it is not surprising that he applied this concept to his residence.


Great Clock Outdoors 1



In addition to the Chinese gong, the exterior of the home features a separate dial of The Great Clock. Instead, the exterior dial incorporates a 24-hour hand which was purportedly an easier format to read for the people who worked and were enslaved on the property. It was an introduction to the instruments which measured time and how to read it.


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Great Clock Letter 2 of 2 1




Jefferson was not unlike his presidential predecessor George Washington in valuing the importance of time and managing it as a tool. Jefferson valued the artistic and practical nature of clocks throughout Monticello and in the White House. While we have our own modern conceptions of time given how easy it is to maintain, Jefferson’s deep appreciation for timekeepers is evident in the collection he built.

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