Transparent infrared absorbing glass and method of making

A method of manufacturing soda-lime-silica flat glass in a continuous process including feeding raw materials to a melting operation that includes separate liquefying and refining stages, passing from the melting operation to a flat glass forming operation a continuous stream of molten glass having at least 0.45 percent by weight iron expressed as Fe.sub.2 O.sub.3, forming the glass into a flat glass product in the forming operation, melting the raw materials in a thin layer in the liquefying stage while controlling oxidation-reduction conditions in that stage and in subsequent stages so as to yield a glass having at least 35 percent of the iron in the ferrous state expressed as FeO and which when formed into a flat glass product of suitable thickness exhibits the combination of luminous transmittance of at least 65 percent and infrared transmittance of no more than 15 percent.