The 150-Year-Old Art of the US Capitol Gives a Glimpse of Scientific History

Every year, over 3 million visitors pass through the doors of the United States Capitol building. For many, a highlight of this historic building is the Rotunda, the enormous chamber underneath the building’s iconic dome. The floor of the Rotunda is filled with statues of American notables and paintings depicting pivotal scenes in United States history—not to mention gawking tourists and their guides, along with the occasional Congressperson.


Top: The iconic dome of the US Capitol building’s West front, seen from outside
Bottom: An interior view of the Capitol Rotunda, a stunning display of art and history.
Image Credit: Top: Martin Falbisoner, via Wikimedia Commons (CC BY-SA 3.0)
Bottom: Office of the Architect of the Capitol

Despite all this bustle, it’s often the ceiling—rising upward and curving to form the enormous dome—that catches visitors’ attention. At the very top of this dome, suspended 180 feet above the Rotunda floor, stands a 4,664 square foot fresco painted in 1865 by Italian artist Costantino Brumidi. Although the Baroque period was long concluded by the time Brumidi was invited to Washington, he designed the fresco in a high Baroque style—creating a masterpiece that lent a sense of age and prestige to the Capitol.

The fresco is drenched in classical symbolism. Entitled The Apotheosis of Washington, it mirrors an ancient Roman process through which emperors became revered as gods—only here, it’s George Washington seated on a heavenly throne. Draped in royal purple, Washington looks down from above the clouds, surrounded by thirteen maidens representing the original states. At either side, he is flanked by an allegorical female character, Liberty and Victory/Fame. Finally, six groups of figures line the perimeter of the dome, each indicating a pillar of American enterprise.

The Apotheosis of Washington in its entirety. Starting at the bottom and proceeding to the right, the groupings are entitled “War”, “Agriculture”, “Mechanics”, “Commerce”, “Marine”, and “Science”
Image Credit: Architect of the Capitol

As you gaze upward at the work, it could evoke any number of reflections on the nation’s history, ancient mythology, or artistic style. What might not be immediately apparent, though, is the subtle but powerful thread of scientific achievement weaving in and around the glorified figures.

To begin with, one of the six “pillars” is dedicated solely to Science herself. In this grouping, the Roman goddess of wisdom Minerva imparts understanding to three of the American superheroes of science: Next to Minerva stands Benjamin Franklin, known for any number of inventions but primarily credited with early forays into electricity. To his right stands Robert Fulton, who developed the first commercial steamboat as well as the first practical submarine, alongside Samuel Morse—best known for bringing the telegraph to practicality, through his development of Morse Code.

Here’s a closer look at the “Science” grouping. Notice the three scientists to Minerva’s right and the generator next to them.
Image Credit: Architect of the Capitol

While the individuals behind her work with geometrical instruments, Minerva gestures to a curious device: a glass wheel, mounted so that it can spin when a crank is turned. This apparatus, known as a Ramsden machine, was an early form of electrostatic generator: When it spun, the friction between the disk and an attached pair of cloth pads would charge the disk with static electricity—a slightly refined version of shuffling your feet on the carpet to give someone a quick “zap”. This charge could be harnessed via a pair of conducting rods that extended near the disk without touching it: as the rods’ electrons would flee the region surrounding the negatively charged disk, creating a negative voltage.

A Ramsden machine on display at the Musée EDF Electropolis
Image Credit: Arnaud, via Wikimedia Commons (CC BY-SA 3.0)

Electrostatic generators of this type were well known, if not particularly useful, by the time Brumidi began his work. The first modern experiments involving static electricity were conducted in the 16th century, and the Ramsden machine, the first generator to use a flat plate rather than a globe or cylinder, was developed in 1766—almost exactly a century before the fresco was begun. On the other hand, it had been less than 35 years since Michael Faraday had applied the connection between electricity and magnetism to create the first electromagnetic generator, and it would be a long time before the full implications of that invention were realized. Whether the artist chose the older model for aesthetic reasons, because he was more familiar with it, or for some other reason is a matter of speculation.

Although this generator is perhaps the most easily recognizable of the scientific achievements depicted in the Apotheosis, it’s far from being the only one. In fact, it’s closely connected—both physically and conceptually—to another invention of the modern era: batteries. Electric batteries had been developed by Italian physicist Alessandro Volta at the very beginning of the 19th century. However, the first rechargeable batteries, the still common lead-acid batteries, were not invented until 1859, six years before the fresco’s painting—so the fact that the Ramsden machine is depicted charging these batteries actually represents a bold juxtaposition between old and new technologies.

But the role of science and technology in establishing the United States is apparent even in the portions of the fresco that aren’t so explicitly labeled. The “Marine” grouping depicts the Roman gods Neptune and Venus holding up a long cable: the transatlantic telegraph cable. While it may not look like much, the telegraph was a paradigm-shifting invention in the 1800s, and its development is deeply intertwined with United States politics—making it a fitting candidate indeed for such a prominent position in the Capitol building.

Although Samuel Morse is often credited with the invention of the telegraph, a number of scientists were able to develop theoretical models and functional prototypes in the half-century leading up to his work. Many of these were limited in their capabilities and practicality, but the first working telegraph was created by Francis Ronalds in 1816, years before Samuel Morse’s 1837 patent. However, when Ronalds presented his work to the British Admiralty, it was deemed “wholly unnecessary” and the project was scrapped.

In the United States, when Samuel Morse designed his own working telegraph, he recognized the invention’s potential to change the world, especially if it had the government support necessary to become established as infrastructure. For this reason he asked to demonstrate the device before interested Members of Congress in 1838. This was the first public demonstration of his telegraph machine, and he took advantage of the impressed audience to request appropriations for a long-distance cable.

It took until 1842 for this request to be approved, at which point the 27th Congress allowed Morse $30,000 to construct a cable relay between Washington, D.C. and Baltimore. The cable was completed in 1844, when it was inaugurated with another demonstration for congressional Members. This first long-distance telegraph was sent from the Old Supreme Court Chamber and read “What hath God wrought?”, a verse from the Bible’s Book of Numbers. Once the message had been successfully transmitted, Morse’s friend in Baltimore, Alfred Vail, relayed the day’s news—marking the dawn of the era of telecommunications.

(Click to enlarge)
The translated transcript of the telegraph sent from the Old Supreme Court Chamber in the Capitol Building.
Image Credit:Public Domain, via Wikimedia Commons

The telegraph’s design is remarkably simple; Morse’s predecessors had run into more difficulties in finding a way to effectively code messages for ease of transmission rather than in the technical design. Part of the reason Morse was able to find success, aside from the support he received from Congress to make long-distance communication a reality, was his creation of Morse Code. Although some previous iterations had used various binary systems, most were impractical, involving rotating alphanumeric wheels, pith balls hanging on silk threads, black and white flags, and dials that rotated back and forth. Morse code, on the other hand, was an uncomplicated system of dots and dashes that could be sent or received with relative ease.

At its core, the telegraph is simply a series of electrical pulses of high voltage sent along a conducting wire. The “sending key”—the small button that the telegraph operator taps on—is connected to a battery or voltage inducer, and pressed to complete a circuit and allow current to flow; a short pulse is a “dot”, and a longer one is a “dash”.

On the receiving end, Morse used an electromagnet to record the messages. The nature of an electromagnet allows it to attract ferromagnetic materials only when current is flowing. This temporary attraction causes a pen to either draw or emboss the appropriate dots and dashes, leaving a written record of every message.

Following the installation of the Washington-Baltimore line, aides at the Capitol found the telegraph indispensable. Lines were gradually installed to reach other eastern cities, and finally even the west coast. In 1853, President Franklin Pierce approved designs for the new House Chamber which included a dedicated House telegraph office. Finally, the first transatlantic telegraph cable was completed in 1858. Although it quickly became unusable, its more durable replacement was put into service in 1866—just after Brumidi brushed the last dab of paint on the Apotheosis.

We’ve come a long way since then: the telegraph became the telephone, transforming and growing and eventually giving birth to the wireless networks that connect us all today. So although the Apotheosis of Washington fulfils its purpose as an ode to the first President, it also tells another story, one of science history and the importance of innovation to the development of the United States—and the world. Costantino Brumidi seemed to understand how developments on the scientific front could promote progress in all of the other pillars of American enterprise—so let’s hope we remember that too.

—Eleanor Hook

You may also read these articles