The second fraction of the crude petroleum, the kerosene, illuminating oil, or “refined oil,” is likewise ordinarily subjected to a second distilling operation, the main purpose of which is to separate it from any traces of gasoline which would tend to make it highly explosive and dangerous when used in lamps. This re-distillation is followed by a chemical purification, producing the kerosene of commerce, which is not only so safe that it may be heated to a temperature well above 100° F. without danger of giving off any explosive vapour, but is also water-white in colour, crystal clear, and of such purity that it may be burned in a lamp in a closed room without producing offensive odours or smoke. The third major fraction of the crude petroleum is the gas oil which has previously been referred to. In general this product may be marketed without further treatment. [Illustration: Lines for loading oil on vessels anchored from one to two miles off shore. This is a regular practice in Mexico where a deep harbour is not available] [Illustration: Battery of crude stills at the Bayway Refinery, Linden, N. J.] The next and last major fraction is perhaps the most interesting of all. It is from this fraction that the host of lubricating products are obtained and also the paraffine wax which has almost entirely superseded animal and vegetable waxes, not only for candles, but for laundry use, for producing water-proof paper, for sealing preserve jars and for a multitude of minor uses. The first step in the treatment of this “paraffine distillate” or lubricating oil distillate fraction of the crude petroleum is to separate from it the paraffine wax which it carries in solution. This is accomplished by chilling the oil to a very low temperature through the use of refrigerating apparatus. When the oil is thus chilled the dissolved wax therein crystalizes so that the mixture resembles nothing more than slush or mush ice. Having caused the dissolved paraffine to freeze and come out in the form of slush in this fashion, it remains to separate it from the oil. This is accomplished by filtering the mush, still held at its low temperature, through canvas cloths. The oily part of the mush passes freely through the cloth while the solidified particles of wax remain on the face of the fabric. The first two products separated by the chilling and filtering processes are therefore a wax-free oil and an impure paraffine wax. The impure paraffine wax is known as “slack wax” and is melted and poured in a liquid condition into shallow pans, where upon cooling, it solidifies. The pans are then slowly and cautiously heated, and as the temperature of the wax rises, the small quantity of oil which it still carries sweats out of the wax, just as though the wax were actually perspiring.