AV Geeks 16mm Lunch 5-22-2024

Mhm. Mhm. Mhm. Mhm. Mhm. Yeah. All right. Hi everybody. I'm Skip Elshiemer. Welcome to the AV Geeks Lunchtime Streaming Show where we watch old 16 mm films and we often forget to turn off the uh volume on our computer that we use to do um sound checks. Um anyways, uh what we just saw was some raw footage shot by uh cameraman for Coronet Films uh for a uh film about the British Isles. So, lots of picturesque picturesque footage there. Um great stuff. Um let's learn about how uh what happens when our class works together. Enjoy. What's happening in Mrs. Berry's class today? Everyone seems quite busy either reading or writing. They're learning about kinds of communities, cities and towns and villages. Writing and reading are things that we do by ourselves. Doing things by ourselves is one way of getting things done. Mrs. Berry is reminding the class that one of the things they've learned about communities is that people work together to get things done. In class, there are certain things that we can get done, too, by working together. What projects might the class do by sharing the work? Well, Bob is suggesting that they could all build a model of a small community. Arthur thinks that they might make a large painting showing how the town gets its milk. Telling their ideas is part of planning together. Planning together is part of working together. Ann has an idea. She's collected quite a few pictures. They show people working at different jobs. Perhaps the class might make an exhibit of such pictures. It would show many kinds of workers in the community. Bob is listening. It helps to listen to the ideas of others. Ann is usually quiet, but now she is telling her idea. Quiet people often have good ideas if we take time to listen to them. Barbara has something to say, too. She thinks that the class might write a report about communities. Mrs. Berry thinks that all ideas are good ones. Which does the class like best? Jack says that writing the report is a good idea, but he thinks it's something we can do better by ourselves. What about doing the painting? Mrs. Berry remembers that they worked on a painting last week. How many are interested in doing another now? Only two. What about the other ideas? The model and the picture exhibit. Would they like to work on these? All right. That's what they'll do. Now they have to decide where they can work. This part of the room seems like a good place. These tables can be used for the model of the community. This table for the work space for the picture exhibit. And this board for pinning up the pictures. Now the boys and girls will plan their work and decide what things they will need for the project. Bob and Arthur are getting little cartons that will be used for the homes and the buildings of the model. Nancy has colored paper that will be needed for water and grass and streets. Ruth has the paints and brushes for painting the homes and buildings. They'll need paste and scissors, too. Here are cardboard and thumb tacks for putting up the pictures. Ann has her pictures and they'll find more in these old magazines. So, the work is started. It's a few days later and the boys and girls have done a lot of work on their project. Bob and Arthur are working on the downtown section of the model. Jack and Ruth on the neighborhood. Nancy is working on the park. The work has been divided so that each boy and girl has about the same amount to do. Jack is doing the streets and grass of the neighborhood. While Bob has made the streets of the downtown section. Arthur is working on the neighborhood houses. He doesn't mind if the class didn't follow his suggestion to make a painting. He is doing his best with this job. Next time, maybe his suggestion will be used. Ruth is putting the finishing touches on a house. So, by sharing the work and by sharing ideas the work is being done faster and better. And it's more fun, too. But, look. The streets of the downtown area are one color and the streets of the neighborhood another. When the different parts of the model are placed together, that won't look right. Jack talks it over with Bob. Perhaps Mrs. Barry can help. Solving problems together is part of working together. Mrs. Barry asks the boys what they think should be done. Bob has made the dark streets and Jack has made the light-colored streets. But perhaps the dark color is more like streets really are. Together they decide that Jack is going to change the color of the neighborhood streets so that they will match the downtown streets. Let's see how the picture exhibit is coming along. Ann and the others have been selecting more pictures of workers from the magazines and pinning them up. Oh, Joan has brought Ann a picture that she found in a magazine at home. Ann says she likes it better than the one she planned to use. So she'll use Joan's picture. Ann's found out that Tom can use scissors very well. So he's been cutting out most of the pictures they'll need. He's also collected quite a bit of waste paper. He'd better get rid of it. Frank has some spare time and will help him. Two can tidy up faster than one. Like Tom, everyone is trying to do a good job. After the pictures have been cut, Frank mounts them. But Frank's all out of paste. Can he borrow some? Arthur is almost finished with his pasting. Perhaps Arthur can lend his paste to Frank. Working together includes sharing things. Helen is putting up the pictures. She's getting help, too. Ann is making sure that the pictures are lined up straight. When we work together, we combine our ideas and our efforts, and we get more done. The pictures in their exhibit show that many things in communities are also done by people working together. The mailman is one community worker. We depend on him, for he delivers our mail. The clerk helps us with our packages. The bus driver takes us where we want to go. The doctor helps us keep well. The policeman keeps us safe. Yes, people in communities do help one another. And now, the picture exhibit is almost completed. And so is the model. The boys and girls have done these things by working together. Everyone is proud of the work. The different parts of the model fit together to form a whole community. Everyone has had a share in the project. There are some things we do alone, but there are other things we do better if we work together. When we work together, we help others, and others help us. That was quaint. Um so, behind me I have a film scanner set up, and uh I was having problems all day today trying to get it to come up and and work. I think I finally got it, so fingers crossed. This is bearskin. Bearskin. What do you think this film's going to be about? Hm. Enjoy. There was once a young man who enlisted as a soldier. He fought bravely during the war and was always in the front when the bullets rained. But when peace was made, he was dismissed. Both his parents were dead and he had no home. So, he found himself alone in the world. I already know what you're in need of. Gold and possessions shall be yours. But first, I must know if you're fearless, so I won't bestow my money in vain. A soldier and fear? How can those two things go together? Put me to the test. Very well. LOOK BEHIND YOU. I SEE YOU DON'T LACK COURAGE. But there is one other condition which you must fulfill. If it doesn't endanger my salvation. If it does, I'll have nothing to do with it. Yourself. But for the next 7 years, you shall neither wash, nor comb your beard, nor cut your hair, nor nails, nor once say the Lord's prayer. You will give me your coat and in exchange, I will give you a cape and a cloak which you must wear during this time. If you die in these 7 years, then you are mine. But, if you live, then you are free and rich to boot for the rest of your life. Sir, I have risked death many times. You've got yourself a deal. When you wear this cape and put your hand in the pocket, there will always be money. And this shall be your cloak. Where you shall sleep and in no other bed shall you lie. And because of this apparel, you shall be called Bearskin. So, he went forth into the world and enjoyed himself, refraining from nothing that did himself good and his money harm. Compliments of Bearskin. Fearless. During the first year, his appearance was passable. But during the second year, it became worse. Hey. Yeah. Hey, what do you think you're doing? Hey, get out. Get out of here. And so he wandered for four long years. What do you want in here? Sir, I need a place to stay. You can't stay here. Get out. I can pay you for a room. You You pay me enough money. Is this enough? Come on, let's go outside and talk. There's an old barn over there. You can sleep upstairs. And Bearskin wished with all his heart that the 7 years were over. Don't be afraid. Who in the devil are you? Don't be afraid. Bearskin spoke kindly and told the man that he was a wanderer without home or friends. That makes two of us. So, why were you crying? Oh, the war devastated the country. My crops have failed for 3 years in a row, and now the landlord wants to throw me in the debtors' prison because I can't pay him the bill I owe him. If that's your only trouble, I've got plenty of money. You? No. I can't No, no, please, please. I've got plenty more. How can I ever repay you? I know. I have three daughters. When they hear how kind you've been to me, I'm sure one of them will offer you her hand in marriage. In truth, you do look strange. But I'm sure she'll be able to put you to rights again. Oh, it's Papa. Maybe he brought us something. Maybe he brought me a jewelry box. What's that thing he has next to him? Looks like some furs. A fur coat. HE BROUGHT ME A FUR COAT. HE BROUGHT ME A FUR COAT. HE BROUGHT ME a fur coat. HE BROUGHT ME WHERE ARE MY BEAUTIFUL young ladies? Oh, Papa. Papa. What's in the box, Papa? That's for you, my little Did you bring me a fur coat? Well, I didn't bring you a fur coat, but I brought you something mighty pretty. Where's my little baby girl? Oh, she's in the barn. Feeding the chickens. Papa. I brought you something you wanted, too. Although it's mighty tiny. I I don't know whether you'll like it or not. Papa, where'd you get the money for this pin? Girls, I I have something I I want to tell you. I met a man who gave me all the money we need. Papa. Is he a young man? Oh, yes. He's a young man. Tall? Very tall. Very tall. Does he have dark hair? Dark hair and lots of it. What are the color of his eyes? Well, I'm not quite so sure. he handsome, Papa? Well, well, he's very kind and generous. Oh, where is he, Papa? Well, there's something I must tell you first. I I told him when he gave me this money that I thought one of my girls would give him her hand in marriage. Oh. Oh, where is he? He's waiting out in THE HALL. OH. HOW COULD YOU EXPECT ME TO MARRY HIM? I'D I'D RATHER MARRY THE DEVIL THAN MARRY HIM. HE ISN'T EVEN HUMAN. I'D RATHER BURN IN HELL THAN MARRY ANYTHING as ugly as that. But he is human, honey. He He told ME SO HIMSELF. I PROMISED HIM. FATHER, I'd like to meet this man. Let's go out and meet him, mother. This is Bearskin. He's a very kind man. Thank you for helping my family. This is for you. Take good care of it. I shall have to wander as Bearskin for another 3 years. If I don't come back by then, you are free, for I will be dead. But pray to God to keep me alive. Bears like sweet things. If he takes a fancy to you, he'll eat you up. You better do what he says, OR ELSE HE'LL GROWL. OH, IT'S JUST THAT THE wedding will be wonderful because BEAR DANCES WELL. BEARSKIN TRAVELED ALONE ABOUT THE WORLD. He helped the poor and asked them to pray that he might live. At last, the 7 years were over. Here's your old coat back. Give me my green one and we have a deal. Not so fast. First, you've got to make me clean. Now, say the Lord's prayer. Soldier, you've won our little bargain. Don't push me any further. He hired a carriage and returned to the home of his love. The father did not recognize him and placed him between his two eldest daughters. Did you enjoy it? Do you want to tell? I love you so much, honey. Oh. Oh. Perhaps you'd like a fool. I need it myself. Oh. Sister, why don't you stay here? I think I'd like to change into something more suitable for company. I'll be right back. Perhaps I think I should have changed, too. I was Bearskin when you saw me last, but by the grace of God, I've been made clean again. Bearskin come home. Bearskin. Nothing. Oh, but look. The soldier and his bride lived a long and happy life together. As for the other two sisters, it is said that they were so filled with envy and jealousy that one hanged herself from a tree and the other threw herself into a lake and drowned. So, you see, I won. I got two souls for the price of one. Oh, that's a surprise. Uh Tom Davenport uh maintains an archive of um It's not the Southern Folklife Collection, which is at UNC. He has his own archive. Uh and it's great to see he made this film, which is obviously based on some folk tale that just goes dark. Those Those evil uh ladies killed themselves. Wow. That was uh that was really something. Um Let's learn about physical heat transfer. Oh, I'm sorry. This Okay. Physical science, heat and energy transfer. That's I saw the words, but I just didn't say them right. So, here it is. Enjoy. Heat. Heat energy. Energy upon which all life on Earth depends. Heat makes things move. Heat is a form of energy. Like electrical energy. Or chemical energy. Or nuclear energy. All forms of energy can be sources of heat. But there's a special relationship between heat and kinetic energy. The energy of movement. When the movement of a basketball player, for instance, is stopped when his knee rubs against the floor, enough heat is produced to cause what's called a floor burn. Friction always produces heat because heat and kinetic energy are related. For example, a paper airplane flies slowly without much kinetic energy. There's some friction between the paper and the air it passes through. Not much. Not enough for the plane to get significantly warmer as it flies. Compare this with the vast increase in temperature of a spacecraft as it reenters the atmosphere at thousands of miles an hour. Now, friction with the air causes its outer surface to become intensely hot. Its protective tiles glow red. More friction, that is more motion, has produced more heat. Atomic theory offers an explanation for this connection. Every substance, of course, is made of tiny particles, atoms, ions, or molecules. In a liquid or a gas like the atmosphere, these particles are not held together rigidly, so they move constantly in many directions. In a solid, like the tiles on a spacecraft, the particles are bound together into a solid structure. But they still move constantly, vibrating in place. Whatever its state, the more energetically a substance's particles move around, the hotter it is. And the less energetically they move, the colder a substance is. This suggests that heat is really a form of motion, or more specifically, that heat energy is a form of kinetic energy. That's why friction makes substances get hot. When things rub against each other, some of their kinetic energy is transferred to individual particles at their surfaces, making the particles move more rapidly, which is another way of saying that the substances gain heat energy. Kinetic energy is not the only form of energy that can be transformed into heat. When an electric current flows in a circuit, operating an appliance for instance, the electrons that make up the current meet resistance to their flow from the material they're flowing through. When this happens, electrical energy is transformed into heat energy. This conversion of energy is put to work for safety purposes in a fuse. When current becomes dangerously high, enough heat is produced to melt a strip of metal in the fuse and break the circuit it's part of, and so prevent a fire or damage to the appliance. Chemical energy can also be transformed into heat. In a hot air balloon, when propane burns, chemical energy is converted to heat energy and put to work lifting the balloon. Our most important source of energy is the sun. Here, nuclear reactions release enormous amounts of energy, which are eventually transformed into heat. Nuclear reactions also take place much more slowly within our planet in the breakdown of radioactive elements, making a minor contribution to the heat that melts rock beneath the Earth's crust. Sometimes, when this magma breaks through the crust, it comes to the surface as molten lava. Nuclear, chemical, electrical, kinetic. In fact, every form of energy can be a source of heat. But there's an entirely different way for a substance to gain heat energy. Notice, the hot lava is heating the air directly above it, the air it's in contact with. This transfer of heat by contact is called conduction. Conduction also transfers heat within a single substance. Heat applied to one part of a metal rod is conducted to other parts of it and to other materials in contact with it. Conduction proceeds at different rates through different materials. Wooden handles never get as hot as the metal pots and pans they're part of because conduction proceeds faster through metals than through nonmetals. And in airplane engines, the metal aluminum has a double advantage. Not only is it light, but it also conducts heat more quickly than most other metals. Molded into fins along an engine, the metal helps to cool the engine by conducting heat away from the cylinders and passing it harmlessly into the air. Aluminum is also a good conductor of electricity. In fact, most of the substances, like aluminum, that are good conductors of electricity, also turn out to be the best conductors of heat. Atomic theory suggests that every solid conducts heat by passing vibrations along from particle to particle through its structure. But a metal that is a good electrical conductor has another characteristic. Some of its electrons are relatively free to move from one atom to another. So, electrical conductors can also conduct heat by means of electrons that pass on their kinetic energy. A poor electrical conductor, like the air in our atmosphere, doesn't have free electrons to carry energy. It's an insulator. But what makes air a good insulator is that its particles are so relatively far apart. These are also the reasons why air is useful for insulation against heat. Most insulation in the walls of houses is really a framework for many tiny pockets of air that help keep heat from being transferred out of the house in winter and into the house in summer. Air in the tiny bubbles of Styrofoam prevents the heat of hot drinks from being transferred to your hand by conduction. Heat can also be transferred by currents of liquid or gas. This way of transferring heat is called convection. Glider flight depends on convection currents of air. A pilot looks for places where air is likely to be well heated by conduction. The best candidate is air over a large plowed field of dark soil bathed in sunlight. Here, solar energy enters the soil where some of it is transformed into heat energy. The dark soil of the field grows warm and warms the air above it more than air above fields with green plants are warmed. If green fields surround the dark plowed field, strong convection currents begin, rising streams of air. This is what the pilot wants, an updraft, a convection current of air that can lift the glider to a higher altitude as it slowly transfers heat to the cooler air around it. Convection transfers heat not only through the atmosphere, but also through the oceans of the world where currents distribute heat energy through the water. Convection currents even distribute heat in the sun. These flowing currents of higher and lower temperature produce the light and dark patches called granulation. But, how does the sun's heat reach Earth? Neither conduction nor convection will work. Both require the movement of particles within substances to transfer heat. But, there aren't enough particles in space to do the job. The sun's energy comes to us in a third way called radiation. This energy is transmitted in the form of electromagnetic waves. Unlike heat, electromagnetic energy can travel through a vacuum in the form of photons, tiny packets of energy. When photons strike an object on Earth or the Earth itself, some of their energy is transformed into heat energy. Solar collectors make use of this heat energy radiated from the Sun. All bodies in space, stars and dust clouds alike, radiate energy. The very hot objects give off high-energy radiation, including enough visible light to photograph them by. But, very low-energy infrared radiation comes along with the light. Our atmosphere filters out nearly all of it. So, objects that don't have enough energy to radiate light are invisible to us on Earth. But, an infrared telescope in orbit, high above our atmosphere, gives us a whole new view of our universe. We've seen stars that have never been seen before, and clouds of matter in stellar orbits that may be the beginnings of planets. An exploding star, a supernova, gives off great energy. What remains of it may give off no light at all, only energy in the infrared. But, an orbiting infrared telescope is sensitive to those radiations. The orbiting telescope passes on what its sensors have registered. And on Earth, we can see the infrared universe. While all bodies transfer radiation, they don't all do so at the same rate. For example, on a hot day, both the water in a lake and the land around it have received the same energy from the sun. But the land is warmer. Why? Because water absorbs heat energy more slowly than land does. But water also radiates heat more slowly than land. So at night, the water will be warmer than the land because the land has lost heat faster. The rate of heat absorption and radiation also depends not only on the type of substance, but also on a substance's surface. Some fires can radiate intense heat. But the shiny outer surfaces of these firefighters' suits reflect the radiation, absorbing very little of it. An object's surface area also affects the rate at which it radiates heat. A giraffe is a long, thin animal with a lot of body surface exposed to the air. So a giraffe's body radiates heat relatively quickly. An advantage for a big animal in a hot climate. But penguins live in cold climates. A penguin's body is short and stocky, with less surface area exposed that can radiate away precious heat. Even the mass of an object can affect its radiation. The penguin is very massive for a bird. And its body radiates heat relatively slowly. A hummingbird loses heat rapidly because of its small mass and a high metabolism. So, it must eat constantly just to maintain its body temperature. Some living things like rattlesnakes have special organs that can detect infrared radiation. In pits beneath each of a rattler's eyes are organs almost as sensitive to heat radiation as its eyes are to light. Even in the dark, the rattlesnake can find its living food. Humans also have ways of seeing in the infrared. The Earth looks like this in visible light. But, with infrared sensitive film, we can see heat variations that can give information about such things as crop diseases, heat loss in homes, and heat pollution in lakes and rivers. Across our planet, heat has its effects visibly and invisibly. Moving currents of wind and water. Shaping and changing the world and its materials. While overhead, the sun bathes us in its radiance, bringing us the heat on which life itself depends. I was guessing with something like um heat energy transfer that there would be more dramatic or dynamic. Oh, well. That was the mid-80s for you. Educational films pretty much got lame during that time in my in my estimation. But, not like the golden age. Um thanks for joining us today. Very much appreciate your eyeballs and your time watching us. Hopefully, you will join us tomorrow, Thursday. Also, if you are in the triangle area, we're going to be doing a home movie day on Saturday at the top green center from 1:00 to 4:00. And we'll be digitizing people's home movies and home video tapes for free. You have to sign up first come first serve. And we do about 10 minutes 10 15 minutes content. Home movies, please, not um stuff you record off the TV. So, anyways, we'll be doing that. And I'll have more info tomorrow about it. But um we'll be there with some equipment. Some of our team will be there. It'll be fun. Anyways, everybody have a great rest of your day. If you like what you saw, hit the thumbs-up, hit the like, subscribe, and go to ko-fi.com/abgeeks or patreon.com/abgeeks. Those are great ways to support us. Otherwise, we will see you tomorrow. Everybody take care.