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Thread: Ancient Lenses

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    Mustafa Umut Sarac's Avatar
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    Ancient Lenses

    These ancient lenses generally magnify about 1.5 or 2 times. Heinrich Schliemann, the 19th century discoverer of Troy, excavated 48 rock crystal lenses at Troy. This is one of the largest hoards of ancient lenses ever found. These were unfortunately lost for many decades because they were with the missing Trojan gold hoard which disappeared from the Berlin Museum at the end of the Second World War. In recent years the Russians have admitted that the Red Army stole the gold and it is all in Moscow today. The 48 lenses are with these gold artefacts.

    Another large number of crystal lenses exists in Crete, mostly found at Knossos. And yet another hoard exists at Ephesus, in Turkey, though those ones are very unusual because they are concave lenses used to correct for myopia (shortsightedness), some shrinking images by as much as 75%. Most ancient lenses are convex and were used to magnify. At Carthage there are 14 glass lenses and two of rock crystal stored in a drawer in the museum; they have apparently never been displayed. Egypt too has examples one pair of glass lenses was excavated from the wrappings of a mummy and obviously were used as spectacles except that loops around the ears for modernstyle spectacles seem not to have been invented in ancient times. So these may have had some kind of nose loop or may have been held as a lorgnette.

    The oldest evidence of a sophisticated optical capability which I have found goes back as far as 3300 BC. An ivory knife handle was excavated in the 1990s from a predynastic grave of that date at Abydos in Egypt. It belonged to a king. It bears microscopic carvings which could only have been made with, and can only be seen with, a magnifying glass.

    The oldest actual lenses which I have found are from the 4th and 5th Dynasties of ancient Egypt and date to perhaps 2500 BC. These are perfectly ground and polished convex crystal lenses which are used as eyes in statues of that date. One such statue is in the Louvre, in Paris, but the rest are in the Egyptian Museum in Cairo.
    There are many ancient classical texts which specifically describe both magnification and works produced under magnification by craftsmen. For instance, the Roman author Seneca speaks of magnification, and Cicero, Pliny and others described microscopic works of art. I have gathered together all of these texts in my book, The Crystal Sun. It is from Cicero's description of a miniature version of the Iliad so small that it could fit inside a walnut shell that our modern expression, 'in a nutshell', came into use, passed on by Shakespeare's Hamlet into modern usage.

    I even own an ancient lens myself which I was able to purchase. from a friend who collected ancient objects. He had no idea that it was a lens, but he bought it because it had an archaic Greek carving of a flying figure on it. In fact, that wonderful carving in no way interferes with the magnifying properties of the lens, since it is transparent. It was probably added to the lens at a later date in its history, but it offers a convenient way to provide a minimum date for the object.

    I took it along to the Greek and Roman Antiquities Department of the British Museum for a dating of the carving. I was told there that the object was a `fake' because it was made of glass. After much prodding, I got the ,expert' to say that if the object had been crystal, the carving would date from the 6th or 7th century BC. Of course, I didn't believe for a minute that the object was glass, so I took it to the Natural History Museum for an X-ray diffraction analysis. This proved that the object was rock crystal, and hence genuine. The interesting part of the comment by the British Museum expert who insisted my lens was a fake was: `they didn't make these then, it can't be real'.

    No, none of this can be real.

    At the end of this article is a photo I took of a painting of an ancient Greek of the 5th century BC using a telescope. This painting is from a pot excavated at the Acropolis about twenty years ago. The pot fragment has been on display in the Acropolis Museum at Athens for many years, where no one appears to have 'seen' it. Many ancient lenses are on display in museums around the world, falsely labelled of course as counters', buttons', 'gems' and so on, and no one sees' them either.

    What is the answer to this? I call it consensus blindness. People agree not to see what they are convinced cannot exist. 'Everyone knows' that there was no optical technology in antiquity, so consequently when you come across its, staring you in the face, you go blind. End of conflict.

    In fact, optical technology in antiquity sometimes reached extraordinary heights. The Layard Lens in the British Museum dates to the 8th century BC and was excavated in the throne room of the Assyrian King Sargon II's palace in what is today called Iraq. I have carried out a full technical analysis of this lens. I have been able to demonstrate that this rock crystal lens, now cracked and considerably damaged, was originally a perfect convex lens with a flat ('plane') base, which was ground in a special way known to opticians as 'toroidal', - a technique only available for the public since about 1900. Such grinding produces lenses to correct for individual cases of astigmatism. It would be possible to go out into the street today and find someone whose astigmatism was perfectly corrected by the Layard Lens. It was clearly used as a monocle. It perfectly fits the eye aperture, as we can see in the illustration. It is most extraordinary that such a high technology existed in the 8th century BC. And not a single Assyriologist has acknowledged the publication of my study of this important object except for the one who encouraged me in the first place; he was curious as to what the results would be. So it appears that the community of Assyriologists find it convenient not to 'see' my book.
    Another example of optical technology being taken to extraordinary lengths I found in Sweden. The Eastern Vikings had a very extensive crystal lens industry. More than a hundred lenses survive in Sweden and the surrounding countries. None, however, are known from Norway; the Western Vikings were apparently not let in on the secret.

    The Scandinavian archaeologists were delighted at my findings, and they have translated some of my work into Swedish and published it already in a leading archaeological journal there. They had no reason to be blind' because they loved the' fact that I could show that their Vikings were even more interesting than they already thought. I discovered that the Vikings had a microscopic optical industry: they were grinding and polishing lenses the size of rain drops which could magnify three times. This is an astonishing feat and one would marvel at it even today.

    There are many old British lenses as well. I found two collections of them stored in geology collections. Some of them are extraordinarily clever, and have projecting points at the back which I termed resting points', to enable them to be use by craftsmen for magnifying while keeping both hands free; the point does not interfere with the magnifying properties. A similarly ingenious design was produced at Troy, where one crystal lens was perforated with a central hole, through which the craftsman could insert his carving tool, while the magnification all around was undisturbed.

    Ancient telescopes were not a difficult invention once they had the lenses. All you have to do is to hold up a lens in each hand and look through them both at once: thus you have a rudimentary telescope. Even though the image is inverted - it takes a third lens to flip it right way up - this makes no difference if you are, for instance, studying the surface of the moon or looking at the stars. No one can tell if a star is right way up or upside down - it all looks the same. In The Crystal Sun I suggest that primitive telescopes were used in ancient Britain and that Stonehenge was an observatory. I suggest that the outer trilithons may have acted as a base for a perishable dome of wood or wattle, and that the inner trilithons, which are higher, were to serve as the base for a perishable wooden observation platform facing east, for the observation of lunar risings.

    http://www.robert-temple.com/article...onryToday.html

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    Mustafa Umut Sarac's Avatar
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    11th centrury hand carved aspherical viking lens from sweden , same quality of 1950s aspherical lenses

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    Very interesting Mustafa.You would think that something that aloud you to see far or see better would be worth as much as gold,or more back then.

    Mike

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    people always are blind to what they don't want to see
    like great photographers or artists where were "ahead of their time"
    because there is no hoard of research or archive already developed
    people don't believe.

    i wonder did they use them for camera obscuras or just for sight+magnification ...

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    I would expect that Temple's work on ancient lenses is just as thorough and well-researched as his previous research on the Dogon knowledge of Sirius B.

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    Erik Petersson's Avatar
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    Mustafa, could you please provide a link to the Swedish archaeological journal? It would be interesting to learn more. Thanks!

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    gandolfi's Avatar
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    thanks for the read - very interesting.

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    Mustafa Umut Sarac's Avatar
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    Erik ,

    Google for Visby Lens. There are hundreds of articles listed in google. Some from Germany and Rodenstock factory made an extensive research on it.

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    I'd expect the Vikings and more Northerly peoples would have been the discoverers-- being that ice spontaneously forms an array of interesting lenses in nature.

    Might also explain why there are no truly early examples (they simply melted).

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    Mustafa Umut Sarac's Avatar
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    Pupfish ,

    Troy is older than the vikings more than 2200 years and go older and older at the city layers.
    Read the article well.

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