原版英语RAZ 教案(Z1) The Balloon Brothers.pdf
Visit www.readinga- for thousands of books and materials.The Balloon BrothersA Reading AZ Level Z1 Leveled BookWord Count:1,770Writing and ArtWrite a newspaper article from September 19,1783,describing the Montgolfier brothers experiment.Use facts from the book and outside resources.ScienceChoose an experiment from the book.Organize the details of the experiment using the steps of the scientific method.Discuss your results and any new questions with a partner.Connectionswww.readinga-The Balloon BrothersThe Balloon BrothersZZ1Z2LEVELED BOOK Z1Written by David L.DreierIllustrated by Loic DerrienThe Balloon Brotherswww.readinga-Who were the Montgolfier brothers,and why are they remembered?Focus QuestionWritten by David L.DreierIllustrated by Loic DerrienThe Balloon BrothersLevel Z Leveled Book Learning AZWritten by David L.DreierIllustrated by Loic DerrienAll rights reserved.www.readinga-Photo Credits:Page 7:alhovik/123RF;page 8(top):Sarin Images/Granger,NYC;page 8(bottom):Granger,NYC;page 10:Stock Montage,Inc./Alamy Stock Photo;page 14:wamsler/123RFWords to KnowairshipsatomsbuoyancychemistenvelopeexperimentimmersedinflammableintriguedmoleculesphysicistprestigeCorrelationLEVEL Z1WXN/A60+Fountas&PinnellReading RecoveryDRA3Table of ContentsWitnessing the Birth of a New Age .4Two Brothers with Big Ideas .6Constructing“Smoke-Powered”Balloons .9A Balloon Rivalry .10Soaring into the Blue .12The Legacy of Lighter-Than-Air Flight .15Glossary .16Early Balloon Flights near Paris,FranceSept.19,1783Nov.21,1783Dec.1,1783Aug.27,178302135746801MilesKilometers2345FranceParisATLANTIC OCEANMEDITERRANEAN SEASpainGermanyItalyEnglandGonesseVersaillesSaint DenisTuileries GardenBellevilleParisSEINE RIVERThe Balloon Brothers Level Z14Witnessing the Birth of a New AgeAn excited crowd of 130,000 thronged the grounds of the Palace of Versailles(vair-SYE),just outside of Paris,France,on the afternoon of September 19,1783.They had come to see the test flight of a large hot-air balloon built by two French brothers,Joseph-Michel and Jacques-tienne Montgolfier(mon-GOLF-yay).King Louis XVI and Queen Marie Antoinette(an-twon-ET)watched from the palace courtyard.The beautiful silk-and-paper balloon was decorated with gold designs on a blue background.There was tension in the air.Since the dangers of flight were unknown,the passengers in the wicker basket suspended beneath the balloon were not human.Instead,they were a sheep,a rooster,and a duck.5These animals had been chosen as part of a scientific experiment.The sheeps body was considered close enough to a humans to make it a reliable test subject.The rooster was included because,though it was a bird,it couldnt fly very high.The high-flying duck was also included to test the hazards of flight.The Montgolfiers filled their balloon with hot,smoky air from a fire burning in a pit.Shortly after 1:00 pm,the balloon was released.As the crowd looked on in wonder,it rose to a height of about 460 meters(1,500 ft.).Eight minutes later,it settled back to Earth 3.2 kilometers(2 mi.)away.The animals were unharmed from the experience.The age of flightlong a dream of humanityhad finally dawned.The way was now clear for people to fly into the clouds,and the Montgolfiers deserved much of the credit.The Balloon Brothers Level Z16Two Brothers with Big IdeasThe Montgolfier brothers were two of the sixteen children of Pierre and Anne Montgolfier,who lived in a small town in southern France.Pierre was a successful paper manufacturer.His factories were the official suppliers of stationery to the court of King Louis XVI,a contract that gave the Montgolfiers financial security.When Joseph and tienne took over the family business in the 1770s,they had plenty of free time to pursue other interests.In his early forties,Joseph became intrigued with the possibility of flight.Since the 1600s,scientists had been exploring the possibility of making a lighter-than-air craft that would fly because of the principle of buoyancy.No one had yet figured out how to build such a vehicle,however.Buoyancy was first understood by the ancient Greek mathematician Archimedes(ark-uh-MEE-deez).It involves the density of an objectits weight for a given volumecompared with that of a fluid in which it is immersed.(Fluid in this sense can mean either a liquid or a gas.)If the density of an object is less than that of the fluid that surrounds it,the object will experience an upward force.7Joseph suspected that a light gas contained within a lightweight enclosure might create an effective buoyant force.He read about such a gas that several past researchers had reported producing in their experiments.That gas was hydrogen,known at the time as“inflammable air”because of its explosive nature.Scientists had been aware of hydrogen for many years.In 1766,English chemist Henry Cavendish identified the gas as an element and gave it the name“inflammable air.”French chemist Antoine Lavoisier(la-VWAH-zee-ay)renamed it“hydrogen”in 1783.Joseph filled small paper spheres with hydrogen gas and released them.His experiments were disappointing,though;the spheres rose just a few meters before coming back down.Hydrogen atoms are so small that they were able to pass through the paper and escape into the surrounding air.Elements and AtomsElements are the chemical building blocks of the universe.Every element is made up of atomsthe smallest particles of substances that still have the properties of that substance.Oxygen and hydrogen are both elements.One oxygen atom and two hydrogen atoms can combine to form one molecule of water.Elements and AtomsElements are the chemical building blocks of the universe.Every element is made up of atomsthe smallest particles of substances that still have the properties of that substance.Oxygen and hydrogen are both elements.One oxygen atom and two hydrogen atoms can combine to form one molecule of water.The Balloon Brothers Level Z18Joseph looked for another way to create an“ascending machine,”as he called it.One day,he noticed that shirts drying over a smoky fire puffed upward.Like most people,he had often seen smoke rising from chimneys.This,he concluded,was the answer:smoke!In early 1783,the Montgolfiers began burning different kinds of materials to identify ones that produced a lot of smoke.They found that a mixture of damp straw and chopped-up wool released the most smoke of any materials they tested.It also produced a terrible stench.But the smoke did indeed give buoyancy to any sort of light container.The brothers concluded that smoke must contain something unknown with a lifting property.They named this marvelous substance“Montgolfier gas.”Of course,there was no such substance.The lifting effect was caused by the hot air itself.When air gets heated,the molecules within it move around faster,causing the air to expand and become less dense.When contained in a balloon,the lighter air makes the balloon rise.Joseph-Michel MontgolfierJacques-tienne Montgolfier9Constructing“Smoke-Powered”BalloonsWithout understanding the real science behind hot-air balloons,Joseph and tienne continued to believe in the existence of Montgolfier gas and to make foul-smelling smoke.The brothers had no reason to believe that their idea was wrong.After all,their test balloons were working.The brothers experimented by using different materials for the envelope,including silk,paper,and linen.As their work progressed,they also increased the size of their balloons.The balloons rose ever higher into the air.The brothers experiments began to attract attention.A crowd filled the town square in Annonay(AN-on-ey),France,on June 4,1783,for the test of a large balloon made of cloth lined with paper.The crowd watched in amazement as the unoccupied balloon soared some 2,000 meters(6,560 ft.)into the sky.After a ten-minute flight,the balloon landed about 2 kilometers(1.2 mi.)away.Successful test flights such as this one launched a balloon craze in France.From“Ascending Machines”to BalloonsThe“ascending machines”or later,“aerostats”that got the French people so excited were not called“balloons”until sometime after the Montgolfiers made history.That name was adapted from the French word ballon,meaning“a large ball used in games.”From“Ascending Machines”to BalloonsThe“ascending machines”or later,“aerostats”that got the French people so excited were not called“balloons”until sometime after the Montgolfiers made history.That name was adapted from the French word ballon,meaning“a large ball used in games.”The Balloon Brothers Level Z110A Balloon RivalryThe Montgolfier brothers asked the French Academy of Sciences to officially recognize their work.A“seal of approval”from the academy was of great benefit to inventors,enhancing their prestige and earning them the admiration and,hopefully,the support of the king.The academy withheld approval of their work.It decided to take a wait-and-see approach in case someone else invented a better balloon.The Montgolfiers chief rival was a physicist named Jacques Charles(ZHOCK SHARL)who proposed building a hydrogen balloon.The Montgolfiers had long since given up on using hydrogen in favor of their hot-air balloons,but Charles saw great possibilities in this approach.A Better Gas for Balloons:HeliumHydrogen is the lightest elementonly one-fourteenth the weight of airso at first glance it seems like the perfect gas for balloons.However,hydrogen is dangerous to work with because it catches fire and explodes easily.A much better gas for balloons is helium,the second-lightest element.Helium does not catch fire or explode.It is therefore completely safe for use in lighter-than-air flight.Helium was not discovered until the 1880s,so it was not available to balloon makers in the 1700s.A Better Gas for Balloons:HeliumHydrogen is the lightest elementonly one-fourteenth the weight of airso at first glance it seems like the perfect gas for balloons.However,hydrogen is dangerous to work with because it catches fire and explodes easily.A much better gas for balloons is helium,the second-lightest element.Helium does not catch fire or explode.It is therefore completely safe for use in lighter-than-air flight.Helium was not discovered until the 1880s,so it was not available to balloon makers in the 1700s.11In July 1783,with the academys approval,Charles began work on his balloon,financed by public donations.He was assisted by two brothers,Nicolas-Louis and Anne-Jean Robert(roh-BEAR),both professional engineers.The three constructed a small test balloon made of silk with a rubberized surface designed to keep the hydrogen from escaping.In the meantime,King Louis,having heard reports of the Montgolfiers experiments,invited them to Paris.The king wanted the brothers to build a dazzling balloon that would display his glory to all of France.As the kings favorites,the brothers now received government funding for their work.The two teams each wanted to be the first to launch a balloon with human passengers.The race was on,though the rivalry was a reasonably friendly one.As the summer waned,the Montgolfiers and Charles were getting ready to demonstrate their balloons.The Balloon Brothers Level Z112Soaring into the BlueOn August 27,1783,a large crowd gathered at a grassy area in Paris where the Eiffel Tower now stands.They had come to witness the launch of the Charles balloon.Among the onlookers was a famous American,Benjamin Franklin,who was serving as U.S.ambassador to France.The balloon was relatively smallabout 4 meters(13 ft.)in diameterwith alternating red and white stripes.The white stripes had turned yellow,discolored by the rubber solution applied to the silk.The Scientific MethodThe Montgolfier brothers and Jacques Charles aimed to answer a question:Is it possible to construct a lighter-than-air device that will enable people to fly?To answer that question,they followed a procedure known as the“scientific method.”The scientific method has several steps:Ask a question.Do background research.Construct a hypothesis.Test your hypothesis with observations or experiments.Analyze your data and draw a conclusion.Communicate your results.The Scientific MethodThe Montgolfier brothers and Jacques Charles aimed to answer a question:Is it possible to construct a lighter-than-air device that will enable people to fly?To answer that question,they followed a procedure known as the“scientific method.”The scientific method has several steps:Ask a question.Do background research.Construct a hypothesis.Test your hypothesis with observations or experiments.Analyze your data and draw a conclusion.Communicate your results.13In the late afternoon,the unpiloted balloon was released.It rose quickly and flew northeast for less than an hour,landing about 15 kilometers(9 mi.)away in the village of Gonesse.Terrified villagers attacked this strange monster from the heavens with their pitchforks.Now it was the Montgolfiers turn to wow Paris.On September 19,they launched their test balloon with its animal passengers at Versailles.When the animals landed safely,the time for a human trial was finally at hand.Since the flight would be very dangerous,the king felt it should be done by condemned prisoners.However,a science teacher,Jean-Franois Piltre de Rozier(ROZE-ee-ay),and a soldier,the Marquis dArlandes(mar-KEE dar-LOND),volunteered.Their historic flight took place on November 21,this time from the outskirts of Paris.This balloon was even more impressive than the last one;it towered 23 meters(75 ft.)high.The balloon was covered with various golden designs.They included Louiss monogramtwo intertwined capital Lsand a circle of fleurs-de-lis(flur-duh-LEES),stylized lilies that were the symbol of French royalty.Other decorative details included sun disks,the signs of the zodiac,and eagles with their wings outspread.The Balloon Brothers Level Z114With de Rozier and the marquis aboard,the“aerostatic globe”rose into the air.Twenty-five minutes later,it landed about 8 kilometers(5 mi.)away,settling between a pair of windmills outside the city.The two men were hailed as heroes.Benjamin Franklin observed the historic flight.Asked by another spectator what this balloon was good for,he reportedly answered,“What good is a newborn baby?”On December 1,just ten days after the Montgolfiers triumph,Jacques Charles and Nicolas-Louis Robert made the first human ascent in a hydrogen balloon.Taking off from the Tuileries(TWEE-luh-reez)Garden in Paris,they flew for more than two hours,coming down in a town about 36 kilometers(22 mi.)away.In the following years,the Montgolfiers launched several more balloons.The brothers were honored by the French Academy of Sciences,and their father,Pierre,was made a nobleman by King Louis.Do You Know?Modern airships include blimps,which rely solely on gas pressure to maintain their shape,and dirigibles,which have an internal structure.Do You Know?Modern airships include blimps,which rely solely on gas pressure to maintain their shape,and dirigibles,which have an internal structure.a
