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

Experimental notes by Charles Wheatstone, principally concerning the practical implications of reflecting and refracting surfaces in motion, comprising proposals to measure the velocity of light; experiments designed to investigate the phenomenon of the electric spark and electrical light; proposals to measure small intervals of time and human perception of rapidly moving points of light; the duration of luminous discharges including meteors; optical phenomena associated with a revolving cube; brief descriptions of experiments involving light houses performed in Ireland, with diagrams and sketches.