In 1892, Rudolf Von Wagner distinguished soda, potash, double (soda and potash), and fixing (i.e., stabilizing) as types of water glass. The fixing type was "a mixture of silica well saturated with potash water glass and a sodium silicate" used to stabilize inorganic water color pigments on cement work for outdoor signs and murals.Von Wagner, Rudolf (1892; translation of 13th edition by Willian Crookes) Manual of Chemical Technology Von Wagner, Manual of Chemical Technology (1892 translation)Hermann Mayer (1925): Das Wasserglas; Sein Eigenschaften, Fabrikation und Verwendung auf Grund von Erfahrungen und Mitteilungen der Firma Henkel & Cie. (The Water-glass: Its properties, production, and application on the basis of experiences and communications of the firm of Henkel & Co.) Published by Vieweg, Braunschweig, Germany.Morris Schrero (1922): Water-glass: A Bibliography. Published by Carnegie Library, Pittsburgh, Pennsylvania.
