Soleil Scheibler polarimeter, 1887.
© Science Museum / Science & Society Picture Library
A polarimeter measures the angle of rotation of a polarized plane of a beam of light when it pases through an optically active substance, such as a sugar solution. Jean-Baptiste Soleil invented and manufactured his polarization device in 1848, and it was improved by Scheibler in 1870. This example was made by Schmidt and Haensch. The instrument consisted of an optical system which polarised the light, a holder for tubes containing standard columns of solution, and an optical system for analysing the light.