On April 17, 1912, Europeans stopped what they were doing and looked skyward for one of the strangest eclipses of the 20th century. In the Netherlands, the event lasted roughly 2.7 hours, with the Moon eventually obscuring about 96 percent of the Sun’s surface.
The eclipse was unusual because it was a hybrid, an eclipse that shifts between annular and total as the Moon’s shadow crosses Earth. The geometry that day was extraordinarily precise. At the point of greatest eclipse, the Moon’s apparent size exceeded the Sun’s by only a tiny fraction, producing a central path just 1.3 kilometers wide and maximum totality of approximately two seconds.
For people in Rotterdam, protective eclipse glasses were decades away. Observers improvised with smoked glass, photographic plates and other darkened materials, methods that were common at the time but that modern astronomers would consider unsafe.
Added Fact: In southern Netherlands, observers reported a spectacular “string of pearls” effect as sunlight streamed through valleys along the Moon’s irregular edge. Today these brilliant points of light are known as Baily’s beads.
