The history of the telescope in the modern sense began from 1607, when in the Hague, John Lippersgay presented his own invention. But astronomy is one of the oldest sciences, so simpler tools appeared much earlier.
In 1850, Austin Henry Layard, an archaeologist from England, excavated the territory of the ancient city of Nimrud, located in Mesopotamia (now it is Iraq). Among the various finds, he managed to find an unusual object, later called the Nimrud lens.
This is a piece of rock crystal with an age of 3000 years. It is believed that the object was created in 750-710. BC er The shape of the lens is made in the form of an oval. The analysis showed that its focus reaches 11 cm on the flat side, and the focal length is 12 cm. That is, we have the equivalent of a 3-fold magnifying glass.
On the surface there are 12 cavities that hold some liquid trapped by the still untreated crystal. Scientists realized that the lens is able to increase the light, but the focus is far from ideal. Since it is based on natural rock crystal, time has not destroyed the lens.
The purpose of the lens
Researchers are still arguing about the purpose of the Nimrud lens. Some believe that this is just a decorative element used in certain ceremonies. There is an assumption that the lenses were used by Assyrian masters, who created complex engravings. Then the lenses allowed to make small inscriptions on artifacts. However, the astronomical theory of using lenses seems to be weighty. The idea was favored by the paleographer Giovanni Pettinato, who studied Babylonian astronomy. He suggested that the lens served as part of the telescope. This version could explain how the ancient Assyrians knew so much about celestial objects.
Moreover, even Galileo Galilei claimed that telescopes figured in ancient observations. One of the proofs is the description by the Assyrians of Saturn. They believed that the planet is a deity around whom snakes are entwined. If translated into modern manners, the use of the telescope helped the ancient people to see the rings around the gas giant.
Disputes regarding the purpose of the lens continues to this day. The Assyrian records do not mention the use of telescopes, and the Nimrud lens itself could be used as a device for kindling a fire. It is also difficult to confirm that the magnifying capacity of the lens could demonstrate the rings of Saturn. So the question remains open. But this does not prevent Nimrud’s lens from being considered one of the oldest optical devices.