1.We need fire every day，to warm our houses，or to cook our food，or to give us light.Even savage①tribes②use fire for such purposes as these.How do people get the heat which is required to light their fires，and their lamps，or candles，or coal-gas？
2.Most savages get a fire by rubbing two very dry pieces of wood together until they become so hot that at last the wood-dust catches fire.You may try to do this，but I do not think that you will succeed.
①Savage，untrained；uncivilized.
②Tribe，clan；a number of people of the same family or race.
3.Fasten a smooth brass button to a cork so that you can hold it firmly，and rub the button as hard as you can on a rough piece of wood.Soon the metal will become so hot that it will set fire to the head of a common match if it be pressed against it.This shows that friction，or the rubbing of one substance against another，produces heat.
TINDER-BOX，FLINT AND STEEL
（火绒盒，燧石与火镰）
4.Until about sixty years ago，the usual
way to get a light in this country was to rub or strike a piece of the hard stone called flint against a piece of steel.
Try this for yourself.Rub a steel file①with a flint in a dark room，and notice what pretty sparks youget.
5.The sparks from the steel
were caught on some dry tinder placed in a small metal box.Tinder was made by charring or partly burning linen or cotton rags.The sparks made the tinder smoulder②，and then splints of wood tipped with sulphur were pressed against the burning tinder and set on fire.
6.You have learned in a former book that sulphur is a yellow，solid substance which takes fire very easily.The sulphur caught fire from the tinder，and then it set the wood on fire，and so at last a light was obtained.
7.But shortly before the time when Queen Victoria came to the throne，lucifer matches were invented.The little splints of wood which we call “matches”are made out of deal or pine wood whichhas been soaked in melted paraffin③wax to make it burn moreeasily.The “heads”or tips of the matches consist of phosphorus①Steel file，a grooved piece of steel used for smoothing wood or metal.
②Smoulder，burn slowly；show smoke without flame.
③Paraffin，a white substance got from shale，coal-tar，etc.
and chlorate of potash，mixed with glue to make them stick to the wood.Other substances are also used，different manufacturers of matches using slightly different mixtures.
8.Phosphorus is a yellowish substance，like wax，which takes fire so easily that it must always be kept in cold water.It is a very dangerous substance to handle，and if you want to cut it you must hold it under cold water while you are doing so.
9.Chlorate of potash is got in the form of white crystals.It is a useful medicine.Perhaps you have had to suck some chlorate of potash lozenges when you had a sore throat.It is used for tipping matches，because it contains a good deal of the gas known as oxygen，which helps other things to burn.
