Two engravings of the solar eclipse of 1748.
Présentation géographique de l'éclipse de la Terre ilustrates a global/hemispheric projection of the Earth during the eclipse of 1748
It features three hemisphere projections side-by-side. Each circle shows the exact path and movement of the Moon's shadow (penumbra) as it sweeps across different parts of the world—including North America, Europe, and Western Asia—at three distinct intervals of time during the day.
This engraving was ground-breaking for its time because it shifted the perspective from what the eclipse would look like looking up at the sky, to what the shadow would look like looking down at the Earth from space.
The Swiss mathematician and physicist Leonhard Euler (often referred to in Italian as Leonardo Eulero) made monumental contributions to the study, prediction, and observation of solar and lunar eclipses during the 18th century.
Euler approached eclipses both as an active observer and as a theorist solving the complex orbital mechanics of the solar system.
Représentation de l'éclipse du Soleil illustrates a localized, highly detailed regional path map of the eclipse's trajectory in Europe.
Instead of a global view, this chart zooms into a flattened geographical map of Europe. It plots the precise, narrow track of the central "annular path" (where the moon appears perfectly centered inside the sun, creating a "ring of fire") as it passes directly across Scotland, Germany, Poland, and the Black Sea.
It includes strict mathematical timelines and coordinates calculated using Euler's newly formulated lunar equations. This helped local European astronomers know exactly what minute the eclipse would begin in their specific towns.
On July 25, 1748, an annular solar eclipse passed over Europe. Working from a darkened room in Berlin, Euler and his assistants—including the astronomers Christine and Margarethe Kirsch—used a telescope to project the image of the Sun onto a white screen (creating a camera obscura).
They drew a circle on the screen based on pre-calculated predictions to see if the maximum eclipse would perfectly align with the geometry. [1]
The Atmosphere of the Moon: Based on his observations of light refracting around the edge of the Moon during this eclipse, Euler published a famous paper titled “Sur l'atmosphere de la Lune prouvée par la dernier eclipse annulaire du Soleil”. In it, he argued incorrectly but logically for his time that the Moon possessed its own atmosphere.
Before Euler, predicting the exact time and geographical path of a solar eclipse was incredibly difficult due to the irregular, wobbling orbit of the Moon. Euler revolutionized this field through celestial mechanics.
Euler was the first to mathematically tackle the "Three-Body Problem"—the complex gravitational interactions between the Sun, the Earth, and the Moon.
He published breakthrough Lunar Theories and highly precise predictive tables in 1753 and 1772. These mathematical models allowed astronomers to calculate the movements of the Moon so accurately that they could reliably predict future eclipses and help sailors determine longitude at sea.
Remarkably, when Euler compiled his second major lunar theory in 1772, he was completely blind and performed all the incredibly complex astronomical equations entirely in his head.
While attempting to model the Earth-Moon-Sun system, Euler discovered the first three collinear equilibrium points where a small object can maintain a stable position relative to two larger orbiting bodies. Joseph-Louis Lagrange later completed the set. Today, these Euler-Lagrange points (specifically L2) are where we park advanced spacecraft like the James Webb Space Telescope.
This engraving is based on his research papers and observations and is an important historical document.
Because the eclipse was going to happen in July 1748, the sheets were first rushed to print in 1747 as standalone broadsides or single sheets.
They were sold individually to local astronomers, university professors, sailors, and wealthy citizens who wanted to track the eclipse in real-time as it passed over their town.
This is a broadside issue and is much rarer than the later printings that were bound into atlases
The creators:
Leonhard Euler, who provided the cutting-edge astronomical tables required to map the Moon's path with unprecedented accuracy.
The Cartographer: Georg Moritz Lowitz, an astronomer and mathematician who translated Euler’s raw math into these beautiful, readable map engravings.
The Engravers: The physical copperplates were engraved by Ruprecht Adam Schneider and Sebastian Dorn for the Homann Heirs publishing firm.
Original hand colouring.
