(3075)
Numb.80.
PHILOSOPHICAL
TRANSACTIONS.
February 19. 167172
The CONTENTS.
A Letter of Mr. Isaac Newton, Mathematick Professor in the University of Cambridge; containing his New Theory about Light and Colors: Where Light is declared to be not Similar or Homogeneal, but consisting of difform rays, some of which are more refrangible than other: And Colors are affirm'd to be not Qualifications of Light, deriv'd from Refractions of natural Bodies, (as 'tis generally believed;) but Original and Connate properties, which in divers rays are divers: Where several Observations and Experiments are alledged to prove the said Theory.An Accompt of some Books: I. A Description of the EAST-INDIAN COASTS, MALABAR, CORMANDEL, CEYLON, &c. in Dutch, by Phil. Baldæus. II. Antonii le Grand INSTITUTIO PHILOSOPHIAE, secundùm principia Renati Des-Cartes; novâ methodo adornata & explicata. III.An Essay to the Advancement of MUSICK; by Thomas Salmon M. A. Advertisement about Thæon Smyrnæus. An Index for the Tracts of the Year 1671.
A Letter of Mr. Isaac Newton, Professor of the Mathematicks in the University of Cambridge; containing his New Theory about Light and Colors: sent by the Author to the Publisher from Cambridge, Febr. 6. 167172; in order to be communicated to the R. Society.
SIR,
TO perform my late promise to you, I shall without further ceremony acquaint you, that in the beginning of the Year 1666 (at which time I applyed myself to the grinding of Optick glasses of other figures than Spherical,) I procured me a Triangular glass-Prisme, to try therewith the celebrated phœnomena of
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Colours.
