Dated 1849-1875. From Working papers and experimental observations relating to optics including polarisation, photometry, spectra and the characteristics of light, [1840-1875].

Working notes compiled by Charles Wheatstone, principally concerning refraction of light, especially experiments utilising Iceland spar (calcite), mica, quartz and lamina of selenite or hydrated calcium sulphate (gypsum), as media for refraction; axes of elasticity in crystals; polarising prisms; convex lenses; notes entitled 'experiments with the reflecting apparatus'; experiments concerning reflecting surfaces including internal reflection within glass; specifications for proposed refractometer; description of Charles Wheatstone's 'wave apparatus', constructed by Elliot Brothers, opticians, London. With equations, diagrams and sketches.