Unpublished letter and paper, 'Observations on the progress of bodies floating in a stream: with an account of some experiments made in the River Thames, with a view to discover a method for ascertaining the direction of currents' by James Burney Burney writes on observations and experiments relating to the progress and acceleration of bodies that float in a stream, and which often descend faster than the stream itself, a phenomenon that Burney posits is due to perpendicular pressure. Preceded by a follow-up letter providing further clarifications on the paper. Subject: Physics Read to the Royal Society on 16 February and 18 May 1809. August 1808 - May 1809