Return to Abstracts of Patents Return to Abstracts of Patents 500-749 Patent Abstracts557. ------. [DREYFUS, H.] [Production of Formaldehyde and Methanol From Carbon Monoxide or Carbon Dioxide by Catalytic Hydrogenation.] French Patent 492,154, Aug. 12, 1916. See British Patent 157,047 (abs. 528) and French Patent 22,293, (abs. 527). |