Original sentence: Assyrian craftsmen made intricate engravings, and could have used such a lens in their work.Experts on Assyrian archaeology are unconvinced, and doubt that the optical quality of the lens is sufficient to be of much use.It may have been used as a magnifying glass, or as a burning-glass to start fires by concentrating sunlight.Italian scientist Giovanni Pettinato of the University of Rome has proposed that the lens was used as part of a telescope by the ancient Assyrians.Other experts say that serpents occur frequently in Assyrian mythology, and note that there is no mention of a telescope in any of the many surviving Assyrian astronomical writings.The Nimrud lens is a 3000 year old piece of rock crystal, which was unearthed by Austen Henry Layard at the palace of Nimrud in what is now Iraq (originally  in Assyria).The Nimrud lens is currently on display in the British Museum.The ancient Assyrians saw the planet Saturn as a god surrounded by a ring of serpents, which Pettinato suggests was their interpretation of Saturn's rings as seen through a telescope.This would explain why the ancient Assyrians knew so much about astronomy
Edited sentence: However, some scientists are unconvinced, and claim that this lens would have been a poor aid to vision.It is believed to be the world's oldest optical telescope, which may explain why the ancient Assyrians knew so much about astronomy.Some scientists are of the opinion that it was used as a telescope by the ancient Assyrians.The Nimrud lens is a piece of rock crystal, 3000 years old, and unearthed in Assyria-proper by Austen Henry Layard.The Nimrud lens is currently in the British Museum.The ancient Assyrians saw the planet Saturn as a god surrounded by a ring of serpents