Many surviving items of jewellery from the Ancient World can be judged to have optical properties. Some could have been used, theoretically, as lenses even if their original function was entirely decorative. On this web page we present some candidates for possible inclusion in the story.
In 1902 the White Fathers who had been excavating the site of the Phoenician-controlled Ancient Carthage since 1897 found a pair of round spherical 'lenses' with a nominal power of +5.50D in a sarcophagus from the 4th century BC. These were identified as lenses by an oculist in Tunis and subsequently inspected, in 1914, by the ophthalmic optician Harry Taylor FBOA.
In 1885 the British Museum acquired two transparent green glass lenses from House 44 of the San-el-Hagar site (often called Tanis in the literature), a Roman period settlement. Both are quite large. EA22522 is about 6.6cm in diameter and AES27639 is 5.98 x 4.46cm and a very irregular shape. In a recent article Jane Draycott dismissed EA22522 on account of its historic bronze-coloured coating which renders the 'lens' useless.
Our museum possesses two scientific replicas of the Tanis lenses, made from modern Perspex by Dr Allan Mills of Leicester University circa 1998.
In 1929 an archaeological excavation by the University of Michigan uncovered a plano-convex lens of a power of about +10.00D at Kom Washeem to the south west of Cairo. It differed considerably from the Carthaginian find (Lavigerie Museum) but was deemed similar to examples found on Crete (Candia Museum). There are now four 'lenses' in the collection of the Kelsey Archaeological Museum at the University of Michigan, Ann Arbor, all associated with the village of Karanis and classified as 'writing implements'.
Three 'lenses' recovered from a tomb at the Hawara site (2nd c AD) may have been used to direct light, which would qualify them as optical instruments but perhaps not vision aids. Two of these are now at UCL in London and one at the Manchester Museum.
A 'lens' from the Akhmim site was donated to the Ashmolean Museum in 1890.
Mr Forsdyke found a round 'lens' more than an inch in diameter which he dated to between 1600 and 1200 BC, but with a focal length of about one inch is is difficult to assess what ophthalmic use it could have served.
In 1853, a British Museum expedition to the site of Ninevah led by Layard discovered what has traditionally been described as the oldest extant ground lens, dating from perhaps 700-600 BC. The find was oval quartz, plano-convex with irregular toroidal power across the curved surface ranging from +4.00D to +8.00D. The British Optical Association's Bill Barker investigated this from an optician's perspective in 1930 and concluded that the shape, small size (1.6 x 1.4 inches) and level of workmanship (probably ground on a flat lapidary's wheel) dictated against this being an ornamental item or a mere burning glass. He suggested that the lens would neatly cover the human orbital aperture and produce magnification suitable for near work. Although it was found in the context of a pile of material associated with enamel or gem cutting it was speculatively suggested that this was a lens used by the cutter rather than debris associated with his produce.
The early history presented in this section is based partly on notes of Mr William Swaine (1894-1986 - pictured) and Dr Samuel L Fox.
A short bibliography for lens historians:
Ahlstrom, O., 1950, 'Swedish Vikings Used Optical Lenses', Optician May 19 1950, 459-462, 464, 469.
Barker, W. B., 1930, 'The Ninevah Lens', British Journal of Physiological Optics IV (1), 4-6.
Draycott, J., 2013, 'Glass Lenses in Roman Egypt - Literary, Documentary and Archaeological Evidence', Bulletin of the Scientific Instrument Society 117, pp.22-24.
Rohr, M. von, 1932, 'Meniscus Spectacle Lenses', British Journal of Physiological Optics, VI (2), 183-187.
Taylor, H. L., 'The Antiquity of Lenses', American Journal of Physiological Optics 5 (4) pp.514-516.
Taylor, H. L., 1930, 'Lens Work of the Ancients', British Journal of Physiological Optics IV (1), 1-6.
Taylor, H. L., 1930, 'The Origin and Development of Lenses in Ancient Times', British Journal of Physiological Optics IV (2), 97-103.