Abstract: Method of heating glass contacting surfaces, comprising heating the glass contacting surfaces to a predetermined operating temperature by combustion of a hydrocarbon fuel gas mixture which includes 90% by volume of MAPP gas and 10 percent by volume of propane. Another method blends the MAPP with air and/or natural gas. A novel hydrocarbon fuel gas mixture which includes 90% by volume of MAPP gas and 10% by volume of propane.

Abstract: Method of heating glass contacting surfaces, comprising heating the glass contacting surfaces to a predetermined operating temperature by combustion of a hydrocarbon fuel gas mixture which includes 90% by volume of MAPP gas and 10 percent by volume of propane. Another method blends the MAPP with air and/or natural gas. A novel hydrocarbon fuel gas mixture which includes 90% by volume of MAPP gas and 10% by volume of propane.

Abstract: Apparatus which is disclosed comprises a metal mold, a metal plunger and an annular manifold, and includes means for moving the plunger and the manifold between an open position in which the manifold surrounds the plunger and a gob of softened glass can be introduced into the mold and a closed position in which the manifold surrounds the plunger and the latter forms, with the mold and the manifold, a cavity in which a glass part can be formed. The manifold and the plunger have facing walls which are above the mold cavity, have portions which are in close fitting sliding engagement, and, thereabove, portions which diverge away from one another and form an annular space.