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Magnification: how to turn a spyglass into an astronomical telescope

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Abstract

According to the received view, the first spyglass was assembled without any theory of how the instrument magnifies. Galileo, who was the first to use the device as a scientific instrument, improved the power of magnification up to 30 times. How did he accomplish this feat? Galileo does not tell us what he did. We hold that such improvement of magnification is too intricate a problem to be solved by trial and error, accidentally stumbling upon a complex procedure. We construct a plausibility argument and submit that Galileo had a theory of the telescope. He could develop it by analogical reasoning based on the phenomenon of reflection in mirrors—as it was put to use in surveying instruments—and applied to refraction in sets of lenses. Galileo could appeal to this analogy and assume Della Porta’s theory of refraction. He could thus turn the spyglass into a revolutionary scientific instrument—the telescope.

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References

  • Bedini Silvio. (1994) Science and Instruments in Seventeenth Century Italy. Aldershot, Variorum

    Google Scholar 

  • Biagioli Mario. (2006) Galileo’s Instruments of Credit: Telescopes, Images, Secrecy. The University of Chicago Press, Chicago

    Google Scholar 

  • Biagioli, Mario. 2010. Did Galileo copy the telescope? A new Letter by Paolo Sarpi. In The Origins of the Telescope, eds. Albert Van Helden et al., 203–231. Amsterdam: KNAW Press.

  • Brownson C.D. (1981) Euclid’s optics and its compatibility with linear perspective. Archive for history of Exact Sciences 24: 165–194

    Article  MathSciNet  MATH  Google Scholar 

  • Bryden D.J. (1993) Spectacles improved to perfection and approved of by the Royal Society. Annals of Science 50: 1–32

    Article  Google Scholar 

  • Burton Harry (trans). (1945) The optics of Euclid. Journal of the Optical Society of America 35: 358–359

    Article  MathSciNet  Google Scholar 

  • Camerota Filippo. (2004) Galileo’s eye: Linear perspective and visual astronomy. Galilaeana 1: 143–170

    Google Scholar 

  • Della Porta Giovan Battista. (1589) Magia Naturalis Libri XX. Neapoli, Apud Horatium Saluianum

    Google Scholar 

  • Della Porta, Giovan Battista. 1593. De Refractione Optices Parte. Naples: Apud Io. Iacobum Carlinum and Antonium Pacem.

  • Della Porta, Giovan Battista. [1605] 2000. Claudii Ptolemaei Magnae Constructionis Liber Primus. Napoli: Edizioni Scientifiche Italiane s.p.a.

  • Drake, Stillman. 1999a. Exact sciences, primitive instruments, and Galileo. In Essays on Galileo and the History and Philosophy of Science, 3 Vols, eds. Noel Swerdllow and Trevor Levere. Vol. 1, 106–125. Toronto: University of Toronto Press.

  • Drake, Stillman. 1999b. Mathematics, Astronomy, and Physics in the Work of Galileo. In Essays on Galileo and the History and Philosophy of Science, 3 Vols, eds. Noel Swerdllow and Trevor Levere. Vol. 1, 63–89. Toronto: University of Toronto Press.

  • Drake Stillman, Charles Kowal. (1980) Galileo’s sighting of Neptune. Scientific American 243(6): 52–60

    Article  Google Scholar 

  • Dupré Sven. (2003) Galileo’s telescope and celestial light. Journal for the History of Astronom 34: 369–399

    Google Scholar 

  • Dupré Sven. (2005) Ausonio’s mirrors and Galileo’s lenses: The telescope and sixteenth century practical optical knowledge. Galilaeana 2: 145–180

    Google Scholar 

  • Eamon William. (1994) Science and the Secrets of Nature: The Books of Secrets in Medieval and Early Modern Culture. Princeton University Press, Princeton, NJ

    Google Scholar 

  • Favaro, Antonio. [1886] 1964. La libreria di Galileo Galilei. The Source of Science, no. 10. New York: Johnson Reprint Corporation.

  • Favaro, Antonio (ed.) 1890–1909. Le Opere di Galileo Galilei. Edizione Nazionale, 21 Vols. Florence: G. Barbera, reprinted 1929–1939, 1964–1966.

  • Frangenberg Thomas. (1992) The angle of vision: Problems of perspectival representation in the fifteenth and sixteenth centuries. Renaissance Studies 6: 1–45

    Article  Google Scholar 

  • Galileo, Galilei. [1606] 1978. Operations of the geometric and military compass (trans: Drake, Stillman). Washington, DC: Smithsonian Institution Press.

  • Galileo, Galilei. [1610] 1989. Sidereus Nuncius or the Sidereal Messenger (trans: Van Helden, Albert). Chicago: The University of Chicago Press.

  • Galileo, Galilei. [1623] 1960. The assayer. In The Controversy on the Comets of 1618, eds. Drake Stillman and C. D. O’malley, 151–336. Philadelphia: University of Pennsylvania Press.

  • Goldstein R.Bernard, Giora Hon. (2005) Kepler’s move from orbs to orbits: Documenting a revolutionary scientific concept. Perspectives on Science 13: 74–111

    Google Scholar 

  • Hecht Eugene. (1990) Optics, 2nd ed. Addison-Wesley, Reading, MA

    Google Scholar 

  • Hon Giora, Yaakov Zik. (2009) Kepler’s optical part of astronomy (1604): Introducing the ecliptic instrument. Perspectives on Science 17: 307–345

    Article  MathSciNet  Google Scholar 

  • Ilardi Vincent. (1993) Renaissance Florence: The optical capital of the world. The Journal of European Economic 22: 507–541

    Google Scholar 

  • Ilardi Vincent. (2007) Renaissance Vision from Spectacles to Telescope. American Philosophical Society, Philadelphia

    Google Scholar 

  • Kemp Martin. (1978) Science non science and nonsense: The interpretation of Brunelleschi’s perspective. Art History 1: 134–161

    Google Scholar 

  • Kepler, Johannes. [1610] 1965. Conversation With Galileo’s Sidereal Messenger (trans: Rosen, Edward). London: Johnson Reprint Corporation.

  • Lefèvre Wolfgang. (2001) Galileo engineer: Art and modern science. Science in Context 14: 11–27

    Article  Google Scholar 

  • Lewis Michael. (2004) Surveying Instruments of Greece and Rome. Cambridge University Press, Cambridge

    Google Scholar 

  • Lindberg David. (1972) Opticae Thesaurus, with an introduction to the reprint edition. Johnson Reprint Corporation, New York

    Google Scholar 

  • Lindberg David. (1976) Theories of Vision from Al-Kindi to Kepler. University of Chicago Press, Chicago

    Google Scholar 

  • Lindberg, David. 1984. Optics in sixteenth century Italy. In Novità à Celecti e Crisi Dels Saper: Atti del Convegno Internazionale di Studi Galileiani, eds. Paolo Galluzzi et al., 131–148. Firenze; Giunti Barbera.

  • Lindberg David, Geoffry Cantor. (1985) The Discourse of Light From the Middle Ages to the Enlightenment. University of California, Los Angeles

    Google Scholar 

  • Machamer Peter. (1973) Feyerabend and Galileo: The interaction of theories, and the reinterpretation of experience. Studies in History and Philosophy of Science 4: 1–46

    Article  Google Scholar 

  • Malet Antoni. (1990) Keplerian illusions: Geometrical picture vs. optical images in Kepler’s visual theory. Studies in History and Philosophy of Science 21: 1–40

    Article  MathSciNet  Google Scholar 

  • Malet Antoni. (2003) Kepler and the telescope. Annals of Science 60: 107–136

    Article  MathSciNet  MATH  Google Scholar 

  • Malet Antoni. (2005) Early conceptualization of the telescope as an optical instrument. Early Science and Medicine 10: 262–273

    Article  Google Scholar 

  • Molesini Giuseppe et al (1993) Telescopes of Galileo. Applied Optics 32: 6219–6226

    Article  Google Scholar 

  • Neri, Antonio. [1611] 2004. L’Arte vetraria. In The Art of Glass, ed. Michael Cable (trans: Merrett, Christopher). Sheffield: The Society of Glass Technology.

  • Pedersen Olaf. (1974) A Survey of the Almagest. Odense University Press, Odense

    MATH  Google Scholar 

  • Pitt Joseph. (1992) Galileo, Human Knowledge, and the Book of Nature. Kluwer, Boston

    Google Scholar 

  • Reeves Eileen. (1997) Painting the Heavens: Art and Science in The Age of Galileo. Princeton University Press, Princeton, NJ

    Google Scholar 

  • Reeves Eileen. (2008) Galileo’s Glassworks. Harvard University Press, Cambridge

    Google Scholar 

  • Ronchi Vasco. (1957) Optics the Science of Vision (trans: Rosen, Edward). Dover, New York

    Google Scholar 

  • Ronchi, Vasco. 1963. Complexities, advances, and misconceptions in the development of science of vision: What is being discovered. In Scientific Change, ed. Alister Crombie, 542–561. London: Heinemann.

  • Ronchi, Vasco. 1967. The influence of the early development of optics on science and philosophy. In Galileo Man of Science, ed. Ernan Mcmullin, 195–206. New York: Basic Books.

  • Settle Thomas. (1968) Ostilio Ricci, A bridge between Alberti and Galileo. Des Sciences 12: 121–126

    Google Scholar 

  • Settle, Thomas. 1996. Galileo’s Experimental Research. Berlin: Max Planck Institute for the history of science. Preprint 52.

  • Shapiro, Alan. 1990. The optical lectures and the foundations of the theory of optical imagery. In Before Newton, the Life and Times of Isaac Barrow, ed. Mordechi Feingold, 105–178. Cambridge: Cambridge University Press.

  • Shea, William. 1990. Galileo Galilei: An astronomer at work. In Nature, Experiment, and the Science, eds. Trevor Levere and William Shea, 51–76. Boston: Kluwer.

  • Shea William. (1996) The revelations of the telescope. Nuncius 11: 507–526

    Article  Google Scholar 

  • Shumaker Wayne. (1979) The Occult Sciences in the Renaissance. University of California Press, Los Angeles

    Google Scholar 

  • Sirtori Girolamo. (1618) Telescopium: Sive Ars Perficiendi Novum illud Galilaei Visorium Instrumentum ad Sydera. Francofurti, Typis Pauli Iacobi

    Google Scholar 

  • Smith A.Mark. (1996) Ptolemy’s Theory of Visual Perception; an English Translation of the Optics With Introduction and Commentary. The American Philosophical Society, Philadelphia

    MATH  Google Scholar 

  • Smith A.Mark. (1998) Ptolemy, Alhazen, and Kepler and the problem of optical images. Arabic Sciences and Philosophy 8: 9–44

    Article  MATH  Google Scholar 

  • Smith, A. Mark. 2001a. Alhacen’s Theory of Visual Perception, A Critical Edition, With English Translation and Commentary, of the First Three Books of Alhacen’s De Aspectibus. 2 Vols. Philadelphia: American Philosophical Society.

  • Smith A.Mark. (2001b) Practice vs. theory: The background to Galileo’s telescope work. Atti della Fondazione Giorgio Ronchi 1: 149–162

    Google Scholar 

  • Smith A.Mark. (2004) What is the history of medieval optics really about? Proceedings of the American Philosophical Society 148: 180–194

    Google Scholar 

  • Smith A.Mark. (2005) Reflections on the Hockney–Falco thesis: Optical theory and artistic practice in the fifteenth and sixteenth centuries. Early Science and Medicine 10: 163–170

    Article  Google Scholar 

  • Smith A.Mark. (2008) Alhacen on Image Formation and Distortion in Mirrors. American Philosophical Society, Philadelphia

    Google Scholar 

  • Smith, A. Mark. 2010a. Alhacen and Kepler and the origins of modern lens-theory. In The Origins of the Telescope, eds. Albert Van Helden et al., 147–167. Amsterdam: KNAW Press.

  • Smith, A. Mark. 2010b. Alhacen on Refraction. A Critical Edition, With English Translation and Commentary of Book 7 of Alhacen’s De Aspectibus, 2 Vols. Philadelphia: American Philosophical Society.

  • Smith Warren. (1990) Modern Optical Engineering, 2nd ed. McGraw-Hill, New York

    Google Scholar 

  • Strano Gorgio. (2009) La lista della spesa di Galileo: Un documento poco noto sul telescopio. Galilaeana 6: 197–211

    Google Scholar 

  • Unguru Sabtai (trans). (1977) Book I of Witelo’s Perspectiva; an English translation with introduction and commentary. The Polish Academy of Science Press, Warszawa

    Google Scholar 

  • Valleriani Matteo. (2010) Galileo Engineer. Springer, Dordrecht

    Book  Google Scholar 

  • Van Helden Albert. (1974) The telescope in the seventeenth century. Isis 65: 39–58

    Google Scholar 

  • Van Helden Albert. (1975) The historical problem of the invention of the telescope. History of Science 13: 251–263

    MathSciNet  Google Scholar 

  • Van Helden Albert. (1977) The invention of the telescope. Transaction of the American Philosophical Society 67: 3–67

    Google Scholar 

  • Van Helden, Albert. 1981. Divini And Campani: A Forgotten Chapter in The History of The Accademia Del Cimento. Monografia N. 5. Firenze: Istituto E Museo Di Storia Della Scienza.

  • Van Helden, Albert. 2009. Who invented the telescope? Sky & Telescope July: 64–69.

  • Van Helden, Albert. 2010. Galileo and the telescope. In The Origins of the Telescope, eds. Albert Van Helden et al., 183–203. Amsterdam: KNAW Press.

  • Westfall Robert. (1985) Science and patronage; Galileo and the telescope. Isis 76: 11–30

    Article  MathSciNet  Google Scholar 

  • Willach Rolf. (2008) The Long Route to the Invention of the Telescope. American Philosophical Society, Philadelphia

    Google Scholar 

  • Zamberti Bartolomeo. (1537) Euclidis Elementorum Geometricorum Lib. XV. Basileae, Apud Iohannem Hervagium

    Google Scholar 

  • Zik Yaakov. (1999) Galileo and the telescope: The status of theoretical and practical knowledge and techniques of measurement and experimentation in the development of the instrument. Nuncius 14: 31–67

    MathSciNet  Google Scholar 

  • Zik Yaakov. (2001) Science and instruments: The telescope as a scientific instrument at the beginning of the seventeenth century. Perspectives on Science 9: 259–284

    Article  MathSciNet  Google Scholar 

  • Zik Yaakov. (2003) Kepler and the telescope. Nuncius 18: 486–490

    Article  Google Scholar 

  • Zik, Yaakov, and Albert Van Helden. 2003. Between discovery and disclosure: Galileo and the telescope. In Musa Musaei, eds. Bereta Marco et al., 173–190. Firenze: Olschki, pp. 173–190.

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  1. Department of Philosophy, University of Haifa, 31905, Haifa, Israel

    Yaakov Zik & Giora Hon

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  1. Yaakov Zik
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  2. Giora Hon
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Correspondence to Giora Hon.

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Communicated by: Jed Buchwald.

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Zik, Y., Hon, G. Magnification: how to turn a spyglass into an astronomical telescope. Arch. Hist. Exact Sci. 66, 439–464 (2012). https://doi.org/10.1007/s00407-012-0099-4

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