3568.     VOGEL, H.  [Synthesis and Polymerization of Formaldehyde.]  Helv. Chim. Acta, vol. 11, 1928, p. 370-371; British Chem. Abs., 1928, A, p. 508; Chem. Abs., vol. 22, 1928, p. 1756.

        When a mixture of equal volumes of CO and H₂ was passed at 150°-180° over a mixture of pumice and Zn dust with 2% of MgO and 1% of PbO, formaldehyde was formed together with caramellike polymerization products.