LSE4101835 Quadrant electrometer by W. Thomson - in ??s??? La physique populaire?????? by Emile Desbeaux, 1891 by Unknown Artist, (19th century); Private Collection; (add.info.: Quadrant electrometer by W. Thomson - in ??s??? La physique populaire?????? by Emile Desbeaux, 1891); Photo ?? Leonard de Selva.