Unpublished paper, 'Observations on the new theory for explaining the coloured appearances of thin plates, lately published in the Transactions of this Society' by G [Gibbes] Walker Jordan Jordan critiques Isaac Newton's colour theory, attempting to prove his own new theory that colours of natural bodies depend on the distances between their integrant parts rather than on the sizes of these parts. Corrections appear throughout in ink. Subject: Physics Read to the Royal Society on 28 March 1811. 16 February 1811