Unpublished paper, 'The principal substance of Bush's system of natural philosophy collected into as few words as possible' by Edwd [Edward] Bush Bush lists his 17 fundamental principles of natural philosophy, mostly relating to light. His principles include that matter is made up of 'minute impenetrable spherical particles', that light is a sensation, and that light is the cause of celestial motion and the rotation of the sun. Subject: Natural Philosophy / Physics Written by Bush at no 5 Bath Street, Hackey Road [London]. 29 January 1822