. . "FIELD OF THE INVENTIONThis invention relates to a process for converting dimethyl ether to formaldehyde utilizing a catalyst which comprises a mixture of oxides of bismuth, molybdenum and iron.BACKGROUND OF THE INVENTIONFormaldehyde is a chemical used extensively as a reagent, preservative, embalming agent, antiseptic and deodorant, and, industrially, in large quantities in the synthesis of many s" . .