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Home , Ballista, Catapult, Mangonel

Table of Contents

Introduction...... 3

Using the Book...... 4

Safety...... 4

Siege History...... 5

The Tension vs Torsion...... 10 Experiment: Mass vs Distance...... 11 Dueling Catapults...... 12 Conversion of Length...... 14 Calculating Averages...... 15 Elasticity...... 16 Experiment: Testing Rubber Bands...... 17

The Understanding Torsion ...... 20 Experiment: Materials Testing...... 22 Applying Ratios...... 24

The Gravity & Levers...... 26 Prediction...... 27 Experiment: Right on Target...... 28 Force & Motion ...... 30 Experiment: Swinging Weights vs Wheels...... 32

The Challenge Laying to the ...... 36

Standards Addressed ...... 38

Additional Resources...... 45

Bibliography...... 46

1

Introduction Siege might have been ancient inventions built to bring an enemy to the breaking point, but the modern world has found a great deal of delight in them as well . , catapults, and ballistae were once used to destroy castle walls, to break through a line of troops, or to throw objects inside castle walls or on enemy ships . Now, these devices are loved for their ingenious use of science and math – and sometimes just for the sake of entertainment . From the to Middle Earth, catapults, trebuchets, battering rams, ballistae, and more have held our attention captive . Indeed, the entertainment industry has tapped into this fascination for some time: the British comedy Monty Python and the Holy Grail, the epic Lord of the Rings films, and kid comedy Night at the Museum have all featured these flinging devices . Many of the big guns of siege warfare are so popular that they are built all around the world either as models, life-sized constructions, or some variation between the two . From small models built in classrooms in Trenton, New Jersey, to towering reconstructions in French chateaux museums, these historic are capturing the imaginations of young and old alike . Math, physics, , problem solving, and history are all topics that can be enhanced by building and using siege machines . Even building small versions can open up huge doorways to learning .

3 Using the Book TheSiege Machines book is designed to help students use Pitsco’s , Torsion Catapult, Torsion Ballista, and Trebuchet Kits to learn history, construction skills, math, science, and even teamwork . Teachers can use this book to develop activities and lesson plans for the classroom, but it can also be used by a parent and child having fun together at home . Whether directing an entire classroom or helping a single child complete a science fair project, Siege Machines covers a range of math and science topics geared toward Grades 5-8 . But this book also launches loads of fun for folks of all ages . Siege Machines is divided into three primary sections: The Catapults, The Ballista, and The Trebuchet . At the end of the book is a culminating activity as well as a listing of national standards addressed by the book’s activities, resources, and a bibliography .

Safety When using any of the Pitsco siege kits, always adhere to the following rules to prevent injury: • The only approved for the Pitsco Catapult Kit and Trebuchet Kit are those made from modeling clay (available through the Pitsco catalog) . The Torsion Catapult can fire Styrofoam balls or modeling clay balls . The Torsion Ballista fires only Styrofoam balls . • Do not fire the catapult or trebuchet until everyone is clear of the target area. Do not fire directly at anyone . • When launching either device, the operator should take care to not get his or her fingers in the way. • The siege machine operator and anyone within firing range must wear safety glasses.

4 Siege HIstory

The Flinging Begins The Greeks were the first to combine the science What’s in a Name? and engineering necessary to use siege craft as effective weapons of war . They built a variety of When reading the history of siege machines, devices including battering rams, siege towers, and it doesn’t take long to realize that one person’s catapults . trebuchet is another person’s bricole! The first Greek to focus on these new weapons There are numerous names and nicknames for was Dionysius I of Syracuse, who lived in the fourth the siege machines. The trebuchet is sometimes century B C. . Collecting the best men of science and called a blida, bricole, couillard, machina, petrary, engineering that he could hire, Dionysius I built an or valsslonva. Some folks even call a trebuchet a that awed his enemies . His smaller catapults catapult! That is, a gravity catapult. Speaking of threw arrows, , and small stones up to 250 catapults, they were also dubbed onagers, ballistae, yards . His larger ones could toss stones that weighed and , just to name a few. up to 55 pounds . Dionysius I’s extra work on these devices came just in time to help a certain young Macedonian site where it would be used . His army used trees in the leader named Alexander – . area they attacked for the timbers needed to construct the catapults . Alexander’s Conquering Catapults At this time, the catapult and its variations were To be fair, it was Alexander’s father, Philip II of powered by tension . This tension could come from a Macedon, who actually started the refinement of the configuration like the . The operator catapult and other siege weapons . Philip was the first pulled back a wooden or animal horn bow that was to figure out that it was much easier to carry only the built on a frame . They shot this by releasing the string basic parts of the catapults and to build the rest at the holding this bow . Or, they could use the tension from a strong but flexible catapult arm that was pulled back to the catapult frame – much like flinging mashed potatoes from a spoon . One of Alexander’s great achievements was mixing large-scale artillery with the and cavalry . His ingenious use of the various military forces was no match for the many armies he faced as he gained rule over much of Asia . Aside from how he used his military equipment, Alexander also improved it . Hiring engineers, Alexander’s catapults soon found themselves aboard ships as well as on solid ground . After getting limited results from the tension catapult, his engineers developed the torsion catapult for added power . Alexander’s troops were creative in other ways – at times they catapulted barrels of poisonous snakes or hornet’s nests onto enemy ships . Roman ballista

5 Around the World They were often combined with other techniques . For Next to adopt the siege machines into their example, attacking forces might also tunnel under armies were the Romans . They began using the siege a castle wall to weaken its foundation . Then, they machines in the first century B C. ;. many of their would follow up with catapult or trebuchet artillery . historians left detailed descriptions of the devices and As time passed, rulers learned to build that their use in the . were better fortified – they could take the abuse of the Catapults turned into quite the globe-trotting siege machines without as much damage being done . machine . In the sixth and seventh centuries A D. ,. Some historians believe, overall, that in the the Chinese developed catapults that used weight medieval period were not very successful . And when pulled by gravity to power the arm – the early they were successful, starvation was often the tool trebuchet . During the ninth century, catapults were used to defeat a castle . By blocking castle inhabitants used throughout Europe . Even the Vikings used siege from reaching supplies, attackers could starve the weapons when they attacked Paris in 885 . Their siege attacked to the point of surrender or defeat . was unsuccessful, but don’t blame the weapons – the But if siege machines didn’t always bring down Vikings failed to form a complete blockade around the castle walls, they could be used for primitive the city . biological warfare . Besiegers would often find dead animals and try to spread disease by throwing them Crusading Catapults inside the castle walls . In the tenth century, the Crusades began as Christian soldiers from Europe invaded the Middle East, attempting to take the area from the Muslims . Over the next two hundred years, the two forces fought many bloody battles . Perhaps the best-known rivalry was between Richard the Lionheart, king of England, and Saladin, the ruler of Egypt . From within the important coastal town of Acre, Saladin and his troops watched Richard’s forces – along with the French – build catapults and massive siege towers . They began to worry about the siege soon to come . The Muslim soldier Damascus suggested they build their own catapult . The Muslims did build catapults and trebuchets . Instead of throwing rocks, they threw a chemical compound that was afire . The compound made short work of burning the siege towers to the ground . This new twist intensified the battle considerably . But after months of more fighting, Richard finally did take the city .

Medieval Mayhem Catapults and trebuchets were the great artillery Built in 1068 by William the Conqueror, the well-preserved weapons during most of the medieval period – used Warwick Castle in England has been witness to much history. It was rebuilt with stone in the 13th century, and in not only in the Middle East but also in Europe and 2005 it became home to one of the largest modern trebu- other parts of the world . However, the siege machines chets – almost 60 feet tall and weighing 22 tons. were not always used on their own to attack a castle . Photo courtesy of MorgueFile.com 6 The heyday of the siege machine started to wane A Return to the Past in the fifteenth century . Why? and After slumbering for centuries, interest in siege cannons were starting to pick up interest by the machines has made a strong return – not as an military . Ultimately, the cannon put the catapult and of warfare, but as an engine for learning and for trebuchet out of business . historical reconstructions . Though it is reported that Napoleon attempted Catapults in WWII to build a trebuchet in 1851 as an academic exercise, reconstructions of siege machines did not make any Think using the catapult for military purposes is serious headway until the 1980s . This reawakening only ? Think again. The United States did not come easily . Original siege machines did military used catapults during World War II. not survive to the present day, so reconstructions While trying to take Okinawa near the end of the are largely based on studying historical writings and war, Allied forces found the caves lining the coast to drawings . And many of the medieval drawings were be troublesome. These caves provided the Japanese not drawn with accurate proportions and details . military places to take cover and to hide artillery. ARMÉDIÉVAL, a French group that reconstructs American soldiers used steel catapults to fling drums siege devices for museums, started to build a of fire into these caves, making them a less appealing historically accurate trebuchet in 1984 . It was hideout. completely operational in 1987 . ARMÉDIÉVAL has Also, several WWII carrier ships were rigged with continued to make many impressive reconstructions compressed-air catapults for launching seaplanes. that can be seen in museums throughout .

At the Chateau de Castelnaud in France, a museum of features several trebuchet reconstructions. Photo courtesy of Luc Viatour (www.Lucnix.be) via Wikipedia Commons 7 ARMÉDIÉVAL also assisted in building a replica of Edward I’s War Wolf trebuchet, Ludgar, in Scotland . The Medieval Centre in Denmark has also made great headway in the reconstruction of siege machines and medieval life in general . During the 1980s, many classes began building them as a physics activity . In 1986, a group of friends – spurred by a newspaper article about a local college class throwing with devices it built – started a friendly competition to build a device to throw a the farthest distance . Now known as the World Championship Punkin Chunkin contest, the event has grown from a few friends to 72 teams from around the US . In 2004, the event drew more than 20,000 people to Sussex County, Delaware, to watch or take part in the contest . Even in the Ozark hills of Arkansas, a traditionally built, fortified medieval castle is slowly coming together . The Ozark Medieval Fortress was started in 2008 and, when completed, the site will demonstrate how siege machines helped to attack and defend the castle as well as daily life in a castle .

8 The Catapults

9 Tension Vs Torsion An interesting thing about a catapult is there are Torsion two forces from which to choose to make it work: While using tension was a simpler and more tension and torsion . obvious answer to powering a catapult, tension didn’t offer tremendous power . The development of torsion Tension as the driving force increased the catapult’s power The original catapults – as well as the Pitsco significantly . Increasing the power allowed larger Catapult – were operated with tension . They are also ammunition to be used or increased the distance the known as flexion catapults . Tension was created by standard ammunition could be hurled . using a device much like a large mounted on Torsion, which powers the Pitsco Torsion Catapult a frame . The bow part of the device would be made (as well as the Pitsco Torsion Ballista) is the strain of wood or animal horns . These materials could both that develops in a material as it is twisted . We can be bent back to create tension in the materials’ fibers . create torsion by twisting ropes tightly around the When the bow was released, the fibers would quickly catapult arm . At this point, the twisted material spring back into place, flinging the attached object as acts as a spring . Releasing the material allows the a result . material to react to the strain by quickly unwinding – allowing the catapult arm to fly up and release the ammunition . The torsion force built up in the twisted material actually has the energy to return the material to its original state .

Tension catapult

The Pitsco Catapult uses tension created by pulling back the arm attached to a rubber band . This stretches the rubber band . The fibers in the rubber band react just as the fibers in the wooden or animal Torsion catapult horn bows . Releasing the tension makes the attached arm fling forward and release the ammunition . Other styles of catapults used a strong yet flexible piece of wood as the catapult arm . The arm could Uncommon Ropes be pulled back to the bottom of the frame and then The ropes twisted to create torsion were made released to fling the ammunition . from a variety of materials. It was very common to use animal sinew, which is a tendon stretched to use as a cord, instead of the plant fiber rope or nylon rope we have today. Sometimes, the rope was even made from women’s hair!

10 Experiment: Mass vs Distance

The most obvious variable for the catapult is the 4) Assign duties to several people: a person to hold mass of the ammunition . In this experiment, you will the balls and to ensure the correct one is being test clay balls of three different masses and record the tested, a person to load and launch the catapult, a results . person to spot where the ball landed, two people to measure the distance traveled by the ball, and Tools and Materials Needed one person to record the results . If necessary, some • Pitsco Catapult or Torsion Catapult built people can do more than one of these duties . according to the kit instructions • Tape measure Testing and Gathering Data • Digital scale or balance 1) Line up the front of the catapult with the line or • Modeling clay mark on the paper . Carefully load the 1 5-gram. • 15'-20' of white paper such as the plain side of ball on the catapult arm . Taking care not to move wrapping paper or Pitsco’s Range Paper the catapult, pull down the trigger . The clay ball • Tape should leave a slight mark on the white paper, helping to spot where it landed . Preparation 2) Label this mark with the ball’s size and the test 1) Make three balls of clay: one each with a mass of number (for example, something like “#2 – 3 g” 1 5. grams, 3 grams, and 4 5. grams . Use the scale for the second test of the 3-gram ball) . or balance to ensure the balls are the correct mass . 3) Measure from the alignment mark on the paper 2) Find a long, narrow area approximately six meters to the landing mark . Record this measurement in (20 feet) long where the test can be conducted . A the table below . clear section of the classroom, a hallway, or the 4) Do this two more times with the 1 5-gram. ball, gymnasium are good choices . Roll out the paper and record the results each time . so it lies flat . If using wrapping paper, make sure 5) Repeat Steps 1-4 for the 3-gram ball and the 4 5-. the plain side faces up . Tape down the corners of gram ball . Record the results of each test . the paper to hold it in place . 6) Put away all the materials used for the testing . 3) Approximately 30 centimeters (one foot) from one end of the paper, draw a straight line or a mark on the paper . For each test, make sure the front of the catapult is aligned with this line or mark . This will help ensure the distance traveled by the clay balls is accurately measured .

Test 1 (in.) Test 2 (in.) Test 3 (in.)

1.5-gram ball

3-gram ball

4.5-gram ball

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