Understanding Fire (1956)

[Music] early one warm fall evening billy and his mother and father decided to eat supper outdoors and prepared on their outdoor fireplace billy's father had laid the fire with paper wood and charcoal at first only the paper burned they would have to wait for the wood and charcoal to catch on fire meanwhile there are things to do back in the house billy's father warned him not to stand too close to the fire billy had always enjoyed watching fires but he had never before thought much about them what did he already know about fire well he knew about fire engines when fire is out of control it is dangerous and can do a great deal of damage but when fire is under control it can be useful we use fire for cooking fire in the furnace helps keep our houses warm fire in locomotives helps to make them go and there are many more ways we use fire because we have been learning about fire since earliest times many thousands of years ago men first learned to use fire for heat and light since then men have learned more about fire and how to control it and so put it to better use but what is fire what can we find out about it now the wood had started to burn billy could see that and he could feel that the fire was hotter now yes a fire is hot he could see that the fire gave off light a fire gives off heat and light yes billy knew that but how does a fire get started what do you need in order to make a fire you need something to burn of course but can you burn everything billy remembered an experiment with fire his teacher did in school with a stone glass paper wood and charcoal when she put these things over a fire what do you think happened the paper burned almost as soon as the fire touched it then the wood on the left began burning and turned black but what about the other things watch the small piece of charcoal in the middle soon the charcoal began to glow which meant that it was burning but the stone and the glass never did burn so to have a fire you need some material that will burn well or fuel in billy's house coal is burned for heat other people use oil or gas or wood for fuel yes you need fuel to have a fire do you need anything else now the charcoal was burning the charcoal had been in the flames for several minutes why was it burning only now with the experiment that billy saw at school explain it this time the paper was in a different place but it was still the first thing to burn the flame beneath kept making the wood and charcoal hotter and hotter until the wood caught on fire but still not the charcoal the flame kept making it hotter and hotter until finally the charcoal glowed as it caught on fire why didn't the paper and the wood and the charcoal all start burning at the same time because some things have to be hotter than others before they'll burn so billy could see that another thing you need in order to have a fire is enough heat to make the fuel burn something that will burn and enough heat to make it burn is that all you need to have a fire a fire to bake the biscuits for their supper father wanted the poker why he said that by poking the fire he was helping it burn well by making sure that fresh air was getting all around the charcoal air does a fire need air that made billy think of another experiment he'd seen at school watch why did the flame go out as a candle burns it uses up something in the air when it has used up almost all that special something and no fresh air can get to it it starts to go out this special something in the air is called oxygen and so billy knew that a fire needs three things fuel material that will burn enough heat to set the fuel on fire and enough oxygen to keep the fire burning now billy knew more about how we start a fire and about what makes a fire burn and he was glad to know more about some of the ways we use fire but is that enough to know about fire how is a fire put out what can you do to stop a fire billy knew that water is used to put out some fires how does it do that have you ever seen a piece of metal made so hot that it glows so hot that it will set paper on fire but after a few seconds in water it is cool enough that you can hold it in your fingers yes water can cool very hot things remember materials have to be hot enough to burn water will cool them so they can't burn so one way of putting out a fire is to cool the material that is burning when oil or gasoline is burning it's dangerous to use water because oil and gasoline float on water fires like this are put out in another way special fire extinguishers are often used to spread a foam over the burning oil how does this put out the fire remember how the candle flame went out when the glass was put over it the flame needed oxygen in order to burn the foam that the firemen used to put out an oil fire covers the fire in the same way that the glass covered the candle flame the foam keeps more air more oxygen from getting to the fire so another way to put out a fire is to take away its supply of air billy and his mother and father enjoyed the steaks they had cooked over the fire in their fireplace billy had learned much about fire and he wanted to learn much more [Music] for instance he wanted to know why the fire in their fireplace was almost out now do you know do you know how to find out more about fire [Music]