On radiant matter; a lecture delivered to the British Association for the Advancement of Science, at Sheffield, Friday, August 22, 1879

To throw light on the title of this lecture I must go back more than sixty years-to 1816. Faraday, then a mere student and ardent experimentalist, was 24 years old, and at this early period of his career he delivered a series of lectures on the General Properties of Matter, and one of them bore the remarkable title, On Radiant Matter. The great philosopher's notes of this lecture are to be found in Dr. Bence Jones's "Life and Letters of Faraday," and I will here quote a passage in which he first employs the expression Radiant Matte?','-