heat for 10 hours. It is then heated again to bring the temperature up to and allowed to cool gradually, usually overnight. When the temperature has again been reduced to the wax is pumped by means of a Kinney pump into 10-gallon pails from which the wax is poured into shallow pans containing approximately 50 lbs of the wax per pan. After the material has cooled to room temperature it is removed from the pans and stacked. 3. Into a 200-gallon cast iron cauldron heated by an oil burner of the household type, (or as required at present by war conditions, heated by bituminous coal) are placed 500 to 900 labs of "formula wax". Note: The amount of "formula wax" to make up a batch various according to the amount of scrap wax which is to be added to the cauldron. Scrap wax represents commercial wax of which "formula wax" is a part. To the amount of "formula wax placed in the cauldron are added 19½% Paraffin (133 degrees-135 °F., usual source Standard Oil of New Jersey) and 2% stearine pitch (M. P. 40 Degrees Celsius). This mixture, consisting of "formula wax", paraffin and stearine pitch, represents commercial wax. Finally, commercial scrap wax of the composition given above in added until the total weight of the mixture is approximately 1,600 lbs. This mixture is usually heated beginning at 12 midnight and carried through until the temperature is 410-415 °F. at 8 am. Note; This may be regarded as standard procedure, although at the present time (Dec. 1943) this has been modified so that only Sunday nights is this done. On other days of the week except for Saturday the kettles are started at 6 am. This method was adopted due to man shortages which necessitated starting the molding operation later in the day.) At this time a congealing point is taken and the necessary adjustments made (see under "tests") after which the mixture is transferred to a closed agitating tank by means of a Kinney pump, the latter forced the hot material through a 2" pipe. 4. To the mixture in the agitation tank, there is added 3/10 percent Johns-Manville # 503 Filter Aid. The temperature is maintained at . by means of a ring gas burner, at the bottom of the tank. At this temperature the wax is supplied by a Worthington pump at 30 lbs to a one