1799. -h\ 26.] PROFESSOR YOUNG. 235 



ingenious instrument, or a new invention, would engage his 

 attention ; but he never spoke of morals, of metaphysics, 

 or of religion. Of the last I never heard him say a word, 

 nothing in favour of any sect, or in opposition to any 

 doctrine ; at the same time, no sceptical doubt, no loose 

 assertion, no idle scoff, ever escaped him. 



On July 8, 1799, he sent from Emmanuel College a 

 paper to the Koyal Society, entitled c Outlines of Ex- 

 periments and Inquiries respecting Sound and Light.' 

 In it he established the great principle of the inter- 

 ference of sounds, and he wrote one section on the 

 analogy of sound and light. In 1800 he referred, in 

 the ' British Magazine,' to a young gentleman of Edin- 

 burgh c who certainly promises, in the course of time, 

 to add considerably to our knowledge of the works 

 of nature, but who had a paper in the " Philosophi- 

 cal Transactions" for 1798, in which what was new 

 was not true, and what was true was not new.' Dr. 

 Eobison, in his article on Music in the fc Encyclopaedia 

 Britannica,' criticised Young's papers. In Nicholson's 

 ' Philosophical Journal ' for 1801 Young answered 

 Eobison, and published an extension of the principles of 

 interferences from sound to light. This was the pre- 

 liminary announcement of his views regarding the 

 undulatory theory of light. 



His first paper on the ' Theory of Light and Colours ' 

 ^ras read to the Royal Society, November 12, 1801. 

 His second paper on this subject was read July 1, 1802, 

 and his third November 24, 1803. His 'Syllabus of 

 Lectures at the Royal Institution,' dated January 19, 

 1802, p. 116, gives the first printed account of his views. 



