GIRLS, as well as boys, need to understand about kerosene explosions. A great many fatal accidents happen from trying to pour a little kerosene on the fire to make it kindle better, and also by pouring oil into a lamp while it is lighted. Most persons suppose that it is the kerosene itself which explodes, and that if they are very careful to keep the oil itself from being touched by the fire or the light, there will be no danger. But this is not so.

If a can or a lamp is left about half full of kerosene oil, the oil will dry up, that is, "evaporate," a little, and will form, by mingling with the air in the upper part, a very explosive gas. You cannot see this gas any more than you can see air.

But if it is disturbed and driven out, and a blaze reaches it, there will be a terrible explosion, although the blaze did not touch the oil. There are several other liquids used in houses and workshops, which will produce an explosive vapor in this way. Benzine is one; burning-fluid is another; and naphtha, alcohol, ether, and chloroform may do the same thing.

In a New York workshop lately, there was a can of benzine, or gasoline, standing on the floor. A boy lighted a cigarette, and threw the burning match on the floor close to the can. He did not dream there was any danger, because the liquid was corked up in the can. But there was a great explosion, and he was badly hurt. This seems very mysterious. The probability is that the can had been standing there quite a while, and a good deal of vapor had formed, some of which had leaked out around the stopper, and was hanging in a sort of invisible cloud over and around the can; and this cloud, when the match struck it, exploded. Suppose a girl tries to fill a kerosene lamp with-out first blowing it out. Of course the lamp is nearly empty, or she would not care to fill it.

This empty space is filled with a cloud of explosive vapor arising from the oil in the lamp. When she pushes the nozzle of the can into the lamp at the top, and begins to pour, the oil, running into the lamp fills the empty space; and pushes the cloud of explosive vapor up; the vapor is obliged to pour out over the edges of the lamp, at the top, into the room outside. Of course it strikes against the blazing wick, which the girl is holding down by one side. The blaze of the wick sets the invisible cloud of vapor on fire, and there is an explosion which ignites the oil, and scatters it over her clothing and over the furniture of the room. This is the way in which a kerosene lamp bursts. The same thing may happen when a girl pours the oil over the fire in the range or stove, if there is a cloud of explosive vapor in the upper part of the can, or if the stove is hot enough to vaporize quickly some of the oil as it falls. Remember that it is not the oil, but the invisible vapor, which explodes. Taking care of the oil will not protect you. There is no safety except in the rule: Never pour oil on a lighted fire or into a lighted lamp.



A Civil Engineer.