1618-1669

Dutch physicist whose De lucis natura proprietate (1662) contains many bold conjectures about light, including the assertion that light is not a corporeal body, as well as commentary on Willebrord Snell's unpublished law of light refraction. Vossius also claimed comets were real bodies, not specters or illusions; that a vacuum existed above Earth's atmosphere; and that sea water could not rise through subterranean channels to form mountain rivers, maintaining instead that all rivers come from rain-water (1666).