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Lenses In Antiquity

The ancient Greeks seem to have thought of just about everything. True, they didn't conceive of silicon chips or H-bombs, but they did know rudimentary optics. Excavations down the years have yielded hundreds of lenses ground from quartz crystals. (Later, the Romans used glass.) Many of these early lenses were articles of high craftsmanship, being accurately spherical and wellpolished. Lathes were evidently available for grinding the rock crystal into appropriate shapes. Some ancient lenses had holes drilled through them, possibly so that they could be carried around the neck on cords. These seem to have been used for kindling fires. Most lenses, though, were probably magnifiers for authenticating seals and for carving gems.

(Sines, George, and Sakellarakis, Yannis A.; "Lenses in Antiquity," American Journal of Archaeology, 91:191, 1987.)

Comment. We wonder if any ancient Greeks ever put two of these lenses together to make a telescope. Such a tan dem arrangement of lenses seems such a natural experiment; i.e., if one is good, two will be better!

Ancients probably ground lenses with bow-driven spindles The ancients probably ground lenses with the aid of bow-driven spindles.

From Science Frontiers #53, SEP-OCT 1987. 1987-2000 William R. Corliss

Science Frontiers Sourcebook Project Reviewed in:

Quotes

  • "A sourcebook of unexplained phenomena is therefore a valuable addition to a collection of scientific literature. William R. Corliss has provided this in the past with his source books of scientific anomalies in several subjects, and now he has provided it for astronomy. He has done an excellent job of collecting and editing a large amount of material, taken in part from scientific journals and in part from scientific reporting in the popular or semi-scientific press." -- "The Mysterious Universe: A Handbook of Astronomical Anomalies", reviwed by Thomas Gold, Cornell University, in Icarus, vol.41, 1980

  • "An interesting, systematic presentation of unusual weather [..] This book is recommended for a general audience" --"Corliss, William R., Tornados, Dark Days, Anomalous Precipitation, and Related Weather Phenomena, Sourcebook Project, 1983.", revieweed in Choice, September 1983
  • "..the science is necessarily somewhat speculative, but Corliss's symthesis is based on reputable sources." -- "Corliss, William R. (Compiler). Lightning, Auroras, Nocturnal Lights, and Related Luminous Phenomena" reviwed by Joseph M. Moran, Univ. of Wisconsin in Science Books and Films, Sep/Oct 1983

  • "Before opening the book, I set certain standards that a volume which treads into dangerous grounds grounds like this must meet. The author scrupulously met, or even exceeded those standards. Each phenomenon is exhaustively documented, with references to scientific journals [..] and extensive quotations" -- "Book Review: The moon and planets: a catalog of astronomical anomalies", The Sourcebook Project, 1985., Corliss, W. R., Journal of the Royal Astronomical Society of Canada, Vol. 81, no. 1 (1987), p. 24., 02/1987