Inventory no. 23801 - Former Display Label
SOLEIL SACCHARIMETER
c.1850
Signed, "Soleil RUE DE L'ODEON 35 À PARIS".
A type of polarizing instrument designed for the analysis of sugar solutions. See J. Soleil (1798-1878) Compte Rendu, 24 (1847), 973-5, also T. Clerget, Ann. Chim. Phys., 3rd series, 26 (1849), 175-207. Between a pair of polarizing prisms are arranged a disc made up of semicircles of right- and left-handed quartz and a double-quartz wedge of variable thickness, known as a compensator. Using white light as a source the field of view appears as one half coloured blue and the other red. By varying the thickness of the wedge the halves can be matched in a pale violet 'transition tint', which makes a sensitive reference point for taking measurements.