Columbia subject headings:
Descartes, René, 1596-1650.
Descartes, René, 1596-1650. Dioptrique.
Refraction--Early works to 1800.
Science--Methodology.
Harvard subject headings:
Descartes, René, 1596-1650--Knowledge--Optics.
Optics--History
Refraction.
Princeton subject headings:
Descartes, René, 1596-1650--Knowledge--Optics.
Optics--History.
Refraction.