Other factors also aided in removing the stigma which has been associated with the name of kero sene. The lighter oils were coming to have a value of their own, and the price of kerosene was some what lower, so that, with less difference between the prices of the two products, there was no longer such strong temptation to mix naphtha with kero sene. Processes of distillation had been materially perfected, and the separation of naphtha from kerosene could be made more accurately. Lamps, also, underwent distinct improvements with the in troduction of the familiar Duplex and Rochester burners, while various safety appliances mini mized the danger of fire if the lamps were acci dentally tipped over. Finally, the elimination of much of the competition in refining brought with it a higher standard of quality through the desire to remove all grounds for complaint, and to extend thereby the popularity and sale of the oil.
At the present time American kerosene is used the world over without a thought of danger, and fires or explosions traceable to its use are few in deed. Where such accidents do occur, they are more often the result of carelessness in handling lamps or of imperfections in the lamps themselves. if the fault is proved to lie in the oil, every effort is made to correct immediately the imperfections in manufacture. The reward of this improvement is found in the practical monopoly which kerosene enjoys to-day in the field of illuminating oils. Rape seed, sesamum, mutton fat, whale oil, tallow and sperm candles, coal oil and shale oil have all been forced far into the background by the supe rior qualities of modern kerosene. Kerosene in an ordinary cheap lamp will give more light and bet ter light than half a dozen of the best sperm candles at a cost of only a fraction of a cent an hour. It would be impossible to calculate the value of the introduction of this cheap and conven ient light to the world at large. It has been un questionably one of the greatest of all modern agents of civilization.
At the present time, of course, the use of illumi nating oil in numerous places has been crowded out by gas or electricity, but it must not be as sumed that the oil lamp is disappearing. In rural districts the world over its use is increasing enor mously, and in some cities modern "arc lamps," using kerosene, are now actually being installed where gas or electricity has been formerly em ployed. In Russia and Sweden, especially, pow erful lamps using petroleum oil and an incandes cent mantle of the Welsbach type, are rapidly growing in popularity. Gas and electricity need
plants and attendants for their manufacture. The petroleum arc lamp needs only compressed air to force the oil under pressure into the orifice where it is burned. This pressure may be furnished by an ordinary bicycle pump. Lamps of 1,500 candle power have proved entirely successful—a power ful lamp of this type having been installed in one of the lighthouses at Alexandria, Egypt. For the same intensity the oil arc lamp is cheaper than either gas or electricity, costing about two cents per hour for a lamp of 800 candle power, as against two and a half cents for gas, and six and a half cents for electricity. The oil lamp has, also, the greatly superior advantage of being available where gas and electricity are not. For this reason the new oil lamp promises to make petroleum, as an illuminant, more important than ever.
Petroleum products, aside from kerosene, also find some use in illuminating purposes, but on a far less important scale. In the process known as the manufacture of air gas, or carbureted air, some one of the lighter distillates, usually gasoline, is employed. Crude petroleum, the so-called gas oil from the tar still, or some other petroleum prod ucts are also used to the extent of millions of bar rels a year, in enriching coal gas and water gas, while to a less degree they are used to make oil gas directly. Oil gas is used widely in lights for buoys at sea, in lighthouses, and in railroad trains, the superior advantage lying in the ease of compression without impairing the quality. The familiar Pintsch system of lights, generally found in the better class of railway cars in this country, utilizes oil gas.
The use of petroleum fuel is a close rival of kerosene in importance. In one form or other— crude, refined oils, or residuum—vast quantities are burned the world over, and every year the con sumption for locomotives, steamers, stationary en gines, and industrial purposes is greater than before. These petroleum fuels perform an invalu able service, especially in countries where other forms of fuel are not abundant or not readily se cured. Thus, in Russia and all Western Asia, in the southwestern part of the United States, and along the Pacific coast of both North and South America, petroleum fuel supplies a long-felt want. Even in countries where other fuel is abundant, easily secured, and relatively cheap, the petroleum stove and the gasoline or naphtha engines meet a multitude of demands which could not be supplied so conveniently and satisfactorily in any other way.