Opticks

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Opticks
The first, 1704, edition of Opticks: or, a treatise of the reflexions, refractions, inflexions and colours of light.
AuthorIsaac Newton
CountryGreat Britain
LanguageEnglish
SubjectOptics
GenreNon-fiction
Publication date
1704
Media typePrint
TextOpticks at Wikisource

Opticks: or, A Treatise of the Reflexions, Refractions, Inflexions and Colours of Light is a book by

physical science and it is considered one of the three major works on optics during the Scientific Revolution (alongside Kepler's Astronomiae Pars Optica and Huygens' Traité de la Lumière
). Newton's name did not appear on the title page of the first edition of Opticks.

Overview

The publication of Opticks represented a major contribution to science, different from but in some ways rivalling the

medium, such as air, into another, such as water or glass. Rather, the Opticks is a study of the nature of light and colour and the various phenomena of diffraction
, which Newton called the "inflexion" of light.

In this book Newton sets forth in full his experiments, first reported to the Royal Society of London in 1672,[2] on dispersion, or the separation of light into a spectrum of its component colours. He demonstrates how the appearance of color arises from selective absorption, reflection, or transmission of the various component parts of the incident light.

The major significance of Newton's work is that it overturned the dogma, attributed to

color circle
that both quantitatively predicts color mixtures and qualitatively describes the perceived similarity among hues.

Newton's contribution to prismatic dispersion was the first to outline multiple-prism arrays. Multiple-prism configurations, as beam expanders, became central to the design of the tunable laser more than 275 years later and set the stage for the development of the multiple-prism dispersion theory.[3][4]

Opticks and the Principia

Opticks differs in many respects from the Principia. It was first published in English rather than in the Latin used by European philosophers, contributing to the development of a vernacular science literature. The book is a model of popular science exposition: although Newton's English is somewhat dated—he shows a fondness for lengthy sentences with much embedded qualifications—the book can still be easily understood by a modern reader. In contrast, few readers of Newton's time found the Principia accessible or even comprehensible. His formal but flexible style shows colloquialisms and metaphorical word choice.

Unlike the Principia, Opticks is not developed using the geometric convention of propositions proved by deduction from either previous propositions, lemmas or first principles (or axioms). Instead, axioms define the meaning of technical terms or fundamental properties of matter and light, and the stated propositions are demonstrated by means of specific, carefully described experiments. The first sentence of the book declares My Design in this Book is not to explain the Properties of Light by Hypotheses, but to propose and prove them by Reason and Experiments. In an Experimentum crucis or "critical experiment" (Book I, Part II, Theorem ii), Newton showed that the color of light corresponded to its "degree of refrangibility" (angle of refraction), and that this angle cannot be changed by additional reflection or refraction or by passing the light through a coloured filter.

The work is a

vade mecum of the experimenter's art, displaying in many examples how to use observation to propose factual generalisations about the physical world and then exclude competing explanations by specific experimental tests. Unlike the Principia, which vowed Non fingo hypotheses or "I make no hypotheses" outside the deductive method, the Opticks develops conjectures about light that go beyond the experimental evidence: for example, that the physical behaviour of light was due its "corpuscular" nature as small particles
, or that perceived colours were harmonically proportioned like the tones of a diatonic musical scale.

Queries

Opticks concludes with a set of "Queries". In the first edition, these were sixteen such Queries; that number was increased in the Latin edition, published in 1706, and then in the revised English edition, published in 1717/18. The first set of Queries were brief, but the later ones became short essays, filling many pages. In the fourth edition of 1730, there were 31 Queries, and it was the famous "31st Query" that, over the next two hundred years, stimulated a great deal of speculation and development on theories of chemical affinity.

These Queries, especially the later ones, deal with a wide range of physical phenomena, far transcending any narrow interpretation of the subject matter of "optics". They concern the nature and transmission of heat; the possible cause of gravity; electrical phenomena; the nature of chemical action; the way in which God created matter in "the Beginning;" the proper way to do science; and even the ethical conduct of human beings. These Queries are not really questions in the ordinary sense. They are almost all posed in the negative, as rhetorical questions. That is, Newton does not ask whether light "is" or "may be" a "body". Rather, he asks: "Is not Light a Body?" Not only does this form indicate that Newton had an answer, but that it may go on for many pages. Clearly, as Stephen Hales (a firm Newtonian of the early eighteenth century) declared, this was Newton's mode of explaining "by Query".

Reception

The Opticks was widely read and debated in England and on the Continent. The early presentation of the work to the Royal Society stimulated a bitter dispute between Newton and

Zur Farbenlehre
(Theory of Colours).

Newtonian science became a central issue in the assault waged by the

James Black
.

Subsequent to Newton, much has been amended. Thomas Young and Augustin-Jean Fresnel showed that the wave theory Christiaan Huygens described in his Treatise on Light (1690) could prove that colour is the visible manifestation of light's wavelength. Science also slowly came to recognize the difference between perception of colour and mathematisable optics. The German poet Goethe, with his epic diatribe Theory of Colours, could not shake the Newtonian foundation – but "one hole Goethe did find in Newton's armour.. Newton had committed himself to the doctrine that refraction without colour was impossible. He therefore thought that the object-glasses of telescopes must for ever remain imperfect, achromatism and refraction being incompatible. This inference was proved by Dollond to be wrong." (John Tyndall, 1880[5])

See also

References

  1. ^ . (Opticks was originally published in 1704).
  2. ^ Newton, Isaac. "Hydrostatics, Optics, Sound and Heat". Retrieved 10 January 2012.
  3. ^ F. J. Duarte and J. A. Piper, Dispersion theory of multiple-prism beam expanders for pulsed dye lasers, Opt. Commun. 43, 303–307 (1982).
  4. ^ P. Rowlands, Newton and Modern Physics (World Scientific, London, 2017).
  5. ^ Popular Science Monthly/Volume 17/July 1880)http://en.wikisource.org/wiki/Popular_Science_Monthly/Volume_17/July_1880/Goethe's_Farbenlehre:_Theory_of_Colors_II
  • Burnley, David The History of the English Language: A Source Book 2nd Edition, 2000, Pearson Education Limited.

External links

Full and free online editions of Newton's Opticks