A book about fireworks
Library of Congress Cataloging-in-Publication Data Chang, Vivian
History of Fireworks / Vivian Chang p.cm.
Includes bibligraphical Referances. ISBN 978-2-82103-103-8
1. Chang, Vivian - Written works. I.Title VC886.9.H3G30 2014 300.86 - vc20 20140214554
Publisher: Chronicle Books
Part I Brief History / o2 Types of Fireworks / 23 Chemistry and Physics / 41
Part II DIY Fireworks / 63 Photographing Fireworks / 75
Part I “You can look up at the stars and every night they're going to be in the same place, but you can launch a six inch shell and you don't really know what it's going to look like until it actually performs.�
Fireworks are so pretty and sometimes you are just into the firework show so much that makes you wonder who created these gorgeous firewoks in the past...
China The first firecrakers The history of fireworks goes back thousands of years to China during the Han dynasty (~200 B.C.), even long before gunpowder was invented. It is believed that the first “firecrackers” were likely chunks of green bamboo, which someone may have thrown onto a fire when dry fuel ran short. The rods sizzled and blackened, and after a while, unexpectedly exploded. Bamboo grows so fast that pockets of air and sap get trapped inside of the plant's segments. When heated, the air inside of the hollow reeds expands, and eventually bursts through the side with a long bam! The strange sound, which had never been heard before, frightened people and animals terribly. The Chinese figured that if it scared living creatures so much, it would probably scare away spirits particularly an evil spirit called Nian, who they believed to eat crops and people. After that, it became customary for them to throw green bamboo onto a fire during the Lunar New Year in order to scare Nian and other spirits far way, thus ensuring happiness and prosperity to their people for the remainder of the year. Soon, the Chinese were using bursting bamboo for other
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special occasions, such as weddings, coronations, and births. The “bursting bamboo”, or pao chuk as the Chinese called it, continued to be used for the next thousand or so years. Discovery of Gunpowder Though a precise date of origin is impossible to determine, most historians believe that the very first pyrotechnic composition - a precursor to gunpowder was first discovered sometime during the Sui and Tang dynasties (~600-900 A.D.) in China. It was most likely discovered accidentally by alchemists who were experimenting with sulfurous mixtures in an attempt to create an elixir of life. During this period of chemical discovery and experimentation, the alchemists kept records of certain poisonous and dangerous compositions that should never be mixed ttincluding one particular mixture consisting of sulfur, saltpeter (potassium nitrate), honey, and arsenic disulfide. The texts make reference to such a mixture igniting accidentally while being cooked over a fire, resulting in a large, bright, hot flame that burned the hands and faces of the alchemists tending to it, and even burnt down the shack there were cooking it in! Despite the
Chapter 01 Brief History
warnings, some alchemists were intrigued by the mixture, and continued experimenting with it to try to find ways to make it more powerful. Their crude mixtures weren't as powerful as modern gunpowder because it didn't contain as much potassium nitrate, but nevertheless burned very hot and bright. It was named huo yao, or the “fire chemical” or “fire drug.” It was soon discovered out that if the “fire drug” was put inside of bamboo tubes and thrown in the fire to be ignited, the gases produced by the burning powder would blast the tube apart with a much louder and more powe r fu l bang th an just green bambo The “Chinese New Year is firecracker was born. a particularly popular O ver time, chemists event that is celebrated discovered that the key with firecrackers to to the vigorous burning usher in the new year of gunpowder was the free of the evil spirits.” fact that saltpeter was rich in oxygen, which it released as it burned. They soon figured out how adding more saltpeter to the mixture made it burn faster, thus making it a more powerful explosive and louder when used in firecrackers. Charcoal the by-product of the incomplete combustion of
cellulose-based plant matter, such as wood was replaced honey and other materials in the early formulas. Through much experimentation, it was discovered that gunpowder-based devices could function in many different ways, depending on their construction. As previously mentioned, when gunpowder was ignited in a confined space, such as a bamboo tube, log, or iron shell, it would generate hot gases under enormous pressure that would eventually rupture the container, creating a load report and sending pieces of the container flying in all directions. If placed in a container with an open end, the burning powder would create a brilliant eruption of flame, sparks, and dense smoke out of the end of the container. The Chinese were well aware of the killing power of these explosive devices, and by the 10th century, began using them for military purposes. The Chinese used their gunpowder to create a variety of explosives, including crude bombs and “fire arrows” — bamboo firecrackers attached to regular arrows and shot at the enemy. The initial intent behind the early Chinese bombs was simply to practice psychological warfare —the terrifying, earth-rattling, lightning-like explosions had never been created by any man-
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Mongolian soliders
using gunpowder as weapon against defend enemies
made device, and they could easily frighten and confuse enemies, forcing them to flee. Eventually, however, efforts by other scientists to improve gun powder (as well as the decoding of Bacon's formulas) led to a warfare revolution in Europe. People created bigger, stronger, more powerful cannons that were capable of propelling large iron balls to far-off targets. It was then that traditional, centuries-old medieval warfare came to an end - because of gunpowder, metal armor could be punctured by bullets, and the once seemingly-impenetrable walls of castles could easily be disintegrated by cannon balls. Soon after, cannon balls were made hollow so that they could be filled with gunpowder and a fuse. If aimed correctly, these flying bombs would explode right before or near the time of impact with the target, which proved very effective in blasting apart walls and showering the enemy with metal shards (shrapnel). In order to compete with and defeat other armies, it became essential that each and every kingdom in Europe be equipped with artillery divisions. To supply the amount of gunpowder needed by these armies, factories known as
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“powderworks� were built in order to grind and mix gunpowder. These facilities typically used the power of mules or running water to turn heavy circular stones in order to crush the power and achieve a homogenous mixture. Not surprisingly, these places would occasionally explode due to a friction-generated spark on the grinding wheel, which often resulted in many fatalities. Armies would often celebrate each victory with thundering booms and bright flashes from their weapons. Rather than being aimed for ground targets, cannons and rockets were pointed towards the sky to make aerial bursts. During 1400-1600, advances in metallurgy allowed for the creation of more advanced cannons, as well smaller gunpowder weapons such as muskets. Though the weapons were inaccurate, unreliable, and no where near as powerful as modern firearms, they were much more advanced than bows, arrows and catapults. Firearms technology in Europe eventually surpassed that of China.
Chapter 01 Brief History
Development of fireworks Meanwhile, the Italians had been fascinated with fireworks ever since the explorer Marco Polo brought back firecrackers from the Orient in 1292. During the Renaissance in Europe (14001500), the Italians began to develop fireworks into a true art form. Since this was a period of artistic creativity and expression, many new fireworks were created for the first time. Military rockets could be modified by adding powered metals and charcoal in order to create bursts of gold and silver sparks in the sky. The Italians were able to develop aerial shells - canisters of of explosive composition that were launched into the sky and exploded at the maximum altitude (the Chinese also developed shells that were spherical in shape). However, the most spectacular firework displays were still those made at ground level. Firework makers discovered how a special slower-burning gunpowder mix could be put in an open-ended tube, which would give off sparks when lit. The dense showers of bright sparks resembled water spewing from a fountain, so the new pyrotechnic device was named accordingly. If rocket engines were attached to a wooden wheel framework, it would spin around rapidly and give
off sparks in a circular pattern. Sculptors would carve giant, detailed models of castles or palaces, which would be adorned with fountains, wheels, and torches. These “temples�, as they were called, were a beautiful and crowd-pleasing sight when ignited. Such displays became in high demand throughout Europe. The idea of controlled fire was fascinating to all, and kings saw no better way to show their wealth and power then by having fireworks at their religious festivals, weddings, and coronation ceremonies.
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1.3
1.2
1.2 Painting from the late 13th century of a Chinese soldier using early gunpowder bombs against the Mongols.
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1.3 Etching of fireworks on London’s River Thames in May 1749 to celebrate the signing of the Treaty of Aix-laChapelle the previous year. Three spectators were killed when a stray explosive ignited a stockpile of fireworks.
1.4 Illustration in the humor magazine Puck depicting an unruly mob celebrating the Fourth of July with fireworks and an angry woman wearing a Society for the Suppression of Unnecessary Noise banner, June 1909.
Chapter 01 Brief History
Fireworks in the New World
1.4
Settlers brought fireworks over to the Americas around the 1600s, where they continued to be used to celebrate special occasions and to impress or scare off Native Americans. The very first 4th of July celebration was in 1777, only one year after the signing of the Declaration of Independence. The United States was still in the midst of the Revolutionary War and the outcome was still uncertain, but beautiful displays of fireworks instilled a sense of hope and patriotism in the citizens of the young nation. When trade relations were established between the U.S. and China less than a century later, Chinese firecrackers became a major import in America. For nearly 1000 years, the only colors that could be produced by fireworks was the orange flash/ sparks from black powder, and white sparks from metal powders. But in southern Italy in the 1830s, scientific advancements in the field of chemistr y enabled pyrotechnicians (the modern term for the old “fire masters�) to create reds, greens, blues, and yellows by adding both a metallic salt (strontium=red, barium=green, copper=blue, sodium=yellow) and a chlorinated powder to the firework composition. Potassium
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Ancient caligraphy
paainting showing people using firecracker.
Li Tian
chlorate (KClO3), a new oxidizer that burned faster and hotter than potassium nitrate, allowed pyrotechnicians to make the new colors deeper and brighter. The harnessing of electrical energy made it possible to obtain pure magnesium and aluminum by electrolysis, which also made fireworks burn brighter. When fine aluminum powder was mixed proportionally with an oxidizer, the resulting mixture - flash powder burned much hotter and faster than black powder, allowing for the manufacture of louder firecrackers and salutes in aerial fireworks.
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The inventer of fireworks A Chinese monk named Li Tian, who lived near the city of Liu Yang in Hunan Province, is credited with the invention of firecrackers about 1,000 years ago. The Chinese people celebrate the invention of the firecracker every April 18 by offering sacrifices to Li Tian. During the Song Dynasty, the local people established a temple to worship Li Tian. The firecrackers, both then and now, are thought to have the power to fend off evil spirits and ghosts that are frightened by the loud bangs of the firecrackers. Firecrackers are used for such purposes today at most events such as births, deaths and birthdays. Chinese New Year is a particularly popular event that is celebrated with firecrackers to usher in the new year free of the evil spirits. To this day the Liu Yang region of Hunan Province remains the main production area in the world for fireworks. It is important to remember the geographic origin of fireworks, because often detractors of the fireworks industry say that fireworks are produced in China to take advantage of cheap labor. But the reality is that
Chapter 01 Brief History
the fireworks industry existed in China long before the advent of the modern era and long before the disparity in east-west wage rates, and hopefully the fireworks industry will exist long after the existence of communism has an effect over the Chinese economy. At the end of the Sui Dynasty (581-618 AD), beginning of the Tang (618-907 AD), the famous alchemist and medicine man Sun Si Miao refined ore in a cave near the eastern side of Liu Yang, Hunan. He developed crackers and later, fireworks. His tools and workbench have been preserved to this day.At the end of the Northern Song and the beginning of the Southern Song dynasties, firecrackers made rapid progress along side the development of social, economic and chemical sciences. In the Qing Dynasty (16441911 AD) firecrackers were presented to the palace as articles of tribute and were greatly enjoyed by the dignitaries of the court.
by land and sea, throughout Asia and as far as Europe. Fireworks were sold abroad in the Guangxun Period (1875-1908 AD) of the Qing Dynasty (1644-1911 AD). At first, fireworks were transported to Guangdong, then to Hong Kong or Macao where they were collected for sale and distribution to Southeast Asia. Some were also sold abroad from Shanghai. During the Xuantong Period (1909-1911 AD) fireworks were sold in twenty countries, including Singapore, India, Korea, Japan, Russia, the Philippines,
Firework Exportion The export of fireworks began with Paozhuang, a private trading company, which had a main store and several branches. In the mid-1800's, Paozhuang began to deal in fireworks, trading
Li Tian The inventor of fireworks
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Britain, America, Sweden, Egypt, Canada, Australia and other Latin America countries. n the 1930's, economic development was hampered by turbulent international politics and persisting warfare. Many firework factories went bankrupt, product range shrank and sales were poor. Over time, the firework industry declined. After the foundation of the People's Republic of China, the fireworks industry began to recover and then entered a golden period after 1978. When theOpen Door Policy came into effect in 1980, worldwide trade began to flourish. In current years, the fireworks export industry has opened to an expanding market. At present, few countries do not import Chinese made fireworks. Presently, there are five bases of fireworks production in China: Liuyan (Hunnan), Beihai (Guangxi), Pingxiang ( Jiangxi), Jianghu ( Jiangsu), and Donguan (Guangdong). Marco Polo Generally Marco Polo is credited with bringing the Chinese gunpowder back to Europe in the 13th century, although some accounts credit the Crusaders with bringing the black powder to Europe as they returned from their journeys.
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Once in Europe, the black powder was used for military purposes, first in rockets, then in canons and guns. Italians were the first Europeans who used the black powder to manufacture fireworks. Germany was the other European country to emerge as a fireworks leader along with Italy in the 18th century. It is interesting to note that many of the leading American display companies are operated by families of Italian descent such as the Grucci family, Rozzi family, and Zambelli family. The English were also fascinated with fireworks. Fireworks became very popular in Great Britain during the reign of Queen Elizabeth I. William Shakespeare mentions fireworks in his works, and fireworks were so much enjoyed by the Queen herself that she created the position of “Fire Master of England.� King James II was so pleased with the fireworks display that celebrated his coronation that he knighted his Fire Master. In the modern era, the American fireworks industry really began to influence Chinese manufacturers following President Nixon's normalization of relations with the Chinese Communist government in the early 1970s. Prior to that time, business was being done between
Chapter 01 Brief History
U.S. and Chinese companies through Hong Kong brokers with little or no direct contact with mainland manufacturers. Throughout the 19 7 0 s a n d 1 9 8 0 s , t h e distribution channels in China were essentially state owned factories producing fireworks that were then exported through government owned provincial export corporations. Products produced in Hunan went through the Hunan Export Corporation, and products produced in Jiangxi went through Jiangxi Export Corporation, and so on. During this period, factories were not required to make a profit, but rather their goal was to keep people working in a region of China where there was no real industry other than agriculture. The Chinese government subsidizedthese factories to keep production going.
Europe Elaborate and colorful display By the mid-13th century, news of gunpowder traveled across the world to Europe via Dominican and Franciscan friars (and undoubtedly circulated through trade), with one friar returning to England
with Chinese-made firecrackers which he gave to English Franciscan monk and Oxford University lecturer Roger Bacon, who became one of the first Europeans to document the study of gunpowder, writing, “If you light it you will get thunder and lightening if you know the trick.� Bacon had figured out that saltpeter (potassium nitrate) was the driving force behind the terrifying noise they made, so he went about discovering a method of purifying this natural mineral to make gunpowder more powerful. But realizing the potential of this substance to revolutionize warfare and cause incalculable death, he did not publish his ultimate findings--but gave it to other scientists it code. By the time of the Renaissance, pyrotechnic schools were training fireworks artists across Europe, particularly in Italy, which became famous for its elaborate and colorful displays. It was the Italians who in the 1830s became the first to incorporate trace amounts of metals and other additives, creating the bright, multihued sparks and sunbursts seen in contemporary fireworks shows. Earlier displays only featured booming sounds, orange flashes and faint golden light.
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Fireworks gained an especially strong following among European rulers, who used them to enchant their subjects and illuminate their castles on important occasions. In England, the earliest recorded display took place on Henry VII’s wedding day in 1486. In 1685, James II’s royal firemaster achieved such a dazzling presentation for the king’s coronation that he received a knighthood. French kings regularly put on spectacular displays at Versailles and other palaces, while Czar Peter the Great of Russia arranged a five-hour pyrotechnic extravaganza to mark the birth of his son. Europeans brought their knowledge and appreciation of fireworks to the New World. According to legend, Captain John Smith set off the first display in Jamestown in 1608. Records show that some American colonists may have gotten a little carried away: A spate of firecrackerrelated pranks in Rhode Island became such a public nuisance that officials banned the “mischievous use of pyrotechnics” in 1731. By 1327, European chemists had refined the composition and use of gunpowder, successfully building ever-more improved--and deadly-cannon which would prove a deciding factor
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during the Hundred Years Wars. Between 1400-1600, advances in metallurgy then led to the creation of even more advanced cannon, as well smaller gunpowder weapons such as muskets-which also arrived in the Americas with the first settlers. Though the weapons were inaccurate and unreliable, they were much more advanced than bows, arrows, and catapults used by America‘s indigenous peoples, which gave Europeans an immediate advantage.
America On July 3, 1776, the day before the Continental Congres s a d o p t e d t h e D e c l a r a t i o n o f Independence, John Adams wrote a letter to his wife in which he presaged the role of fireworks in Fourth of July celebrations. “The day will be most memorable in the history of America,” he predicted. “I am apt to believe that it will be celebrated by succeeding generations as the great anniversary festival. It ought to be solemnized with pomp and parade…bonfires and illuminations [a term for fireworks]…from one end of this continent to the other, from this time forward forevermore.” The following year, fireworks displays
Chapter 01 Brief History
commemorated the fledgling countr y ’s first anniversary, just as they have each subsequent one. They also light up the skies to mark other events of national importance, including presidential inaugurations going all the way back to George Washington’s, and holidays such as New Year’s Eve. In the 1890s, rampant detonation of fireworks, particularly by unskilled ruffians, drove concerned citizens to form the Society for the Suppression of Unnecessary Noise, which lobbied for restrictions. On July 4th, 1777, the first official use of fireworks occurred on the 1st anniversary of the signing of the Declaration of Independence, during what would become the annual July 4th festivities. Amidst the Revolutionary War, the impressive displays of fireworks are said to have “instilled a sense of hope and patriotism in the citizens of the young nation.” Wanting to recapture this festive and reassuring feeling in subsequent years, fireworks became an integral part of Fourth of July festivities from that point on. A century later, when trade relations were established between the US and China, Chinese firecrackers became a major import in America. Over the years, firework displays grew more and more elaborate, gradually working their way
into backyard festivities of everyday families. By the 20th century, hundreds of cities across the U. S. were scheduling annual holiday events centered around elaborate July 4th firework displays-which became more spectacu lar each year. In recent years, Americans have seen some of the best and most magnificent fireworks d i s p l a y s e v er : The U..S. Bi c e n t en n i a l i n 1976 at the Nation's Capital; The Brooklyn Bridge Centennial in 1983; numerous Macy's Extravaganzas; and the inaugurations of President Reagan, Bush, and Clinton. By many accounts, the greatest display of fireworks in American history occurred at midnight at the verge of the new millennium when thousands of towns and cities that didn’t usually offer displays, joined the worldwide celebration. But some say even that paled in comparison to the displays set off for the 100th Anniversary of the Statue of Liberty, on July 4th, 1986.
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“Colored lights blink on and off, racing across the green boughs. Their reflections dance across exquisite glass globes and splinter into shards against tinsel thread and garlands of metallic filaments that disappear underneath the other ornaments and finery. Shadows follow, joyful, laughing sprites. The tree is rich with potential wonder. All it needs is a glance from you to come alive.�
Peony The most common type of firework, the peony shell type is a spherical break of colored stars that burn without a tail effect.
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Chrysanthemum A spherical break of colored stars, similar to a peony, but with stars that leave a visible trail of sparks.
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Mine A mine is a ground firework that expels stars and/or other garnitures into the sky. Mines are shot from a mortar and can project small reports, serpents, small shells and stars
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Multi-break Shells A large shell containing several smaller shells of various sizes and types. The initial burst scatters the shells across the sky before they explode.
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Palm A shell containing a few large comet stars arranged to burst with large tendrils, producing a palm tree-like effect.
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Willow The willow is similar to a chrysanthemum, but with long-burning silver or gold stars that produce a soft, dome-shaped weeping willow-like effect.
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Ring A shell containing a few large comet stars arranged to burst with large tendrils, producing a palm tree-like effect.
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Chapter 02 Types of fireworks
Sound Whistle High pitched often very loud screaming and screeching created by the resonance of gas. This is caused by a very fast strobing (on/off burning stage) of the fuel. The rapid bursts of gas from the fuel vibrate the air many hundreds of times per second causing the familiar whistling sound. It is not – as is commonly thought – made in the conventional way that musical instruments are using specific tube shapes or apertures. Common whistle fuels contain benzoate or salicylate compounds and a suitable oxidizer such as potassium perchlorate. Crackle The firework produces a crackling sound. Hummers Tiny tube fireworks that are ejected into the air spinning with such force that they shred their outer coating, in doing so they whizz and hum. Bangs and report The bang is the most common effect in fireworks and sounds like a gunshot, called a report.
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Fish A shell containing a few large comet stars arranged to burst with large tendrils, producing a palm tree-like effect.
Spider A shell containing a fast burning tailed or charcoal star that is burst very hard so that the stars travel in a straight and flat trajectory before slightly falling and burning out. This appears in the sky as a series of radial lines much like the legs of a spider.
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Chapter 02 Types of fireworks
Saulte A shell intended to produce a loud report rather than a visual effect. Salute shells usually contain flash powder, producing a quick flash followed by a very loud report. Titanium may be added to the flash powder mix to produce a cloud of bright sparks around the flash. Salutes are commonly used in large quantities during finales to create intense noise and brightness. They are often cylindrical in shape to allow for a larger payload of flash powder, but ball shapes are common and cheaper as well. Salutes are also called Maroons. Another type of salute is the lampare. A lampare shell has the flash powder used in a regular salute, but is filled with a flammable liquid. When the shell explodes it has a loud report with a fireball.
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2010 New Year Firewok Show Australia
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Bastille Day Firework Show 2014 Paris, France
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Christamas Day Firework Show 2013 Los Angelos Disney, California, US
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Year End Firework Show 2014 101 BuildingTaipei, Taiwan
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“Excuse me while I kiss the sky. Excuse me while I set the sky on fire! Imagination is the key to my lyrics. The rest is painted with a little science fiction. Imagination is the key to pyrotechnics. The rest is painted with a little chemistry & color. �
Chemistry of Fireworks Creating firework colors is a complex endeavor, requiring considerable art and application of physical science. Excluding propellants or special effects, the points of light ejected from fireworks, termed 'stars', generally require an oxygen-producer, fuel, binder to keep everything where it needs to be, and color producer. There are two mechanisms color production in fireworks, incandescence and luminescence. Incandescence Incandescence is light produced from heat. Heat causes a substance to become hot and glow, initially emitting infrared, then red, orange, yellow, and white light as it becomes increasingly hotter. When the temperature of a firework is controlled, the glow of components, such as charcoal, can be manipulated to be the desired color (temperature) at the proper time. Metals, such as aluminum, magnesium, and titanium, burn very brightly and are useful for increasing the temperature of the firework. Luminescence Luminescence is light produced using energy sources other than heat. Sometimes luminescence is called
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cold light, bec ause it c an occur at room temperature and cooler temperatures. To produce luminescence, energy is absorbed by an electron of an atom or molecule, causing it to become excited, but unstable. When the electron returns to a lower energy state the energy is released in the form of a photon (light). The energy of the photon determines its wavelength or color. Sometimes the salts needed to produce the desired color are unstable. Barium chloride (green) is unstable at room temperatures, so barium must be combined with a more stable compound (e.g., chlorinated rubber). In this case, the chlorine is released in the heat of the burning of the pyrotechnic composition, to then form barium chloride and produce the green color. Copper chloride (blue), on the other hand, is unstable at high temperatures, so the firework cannot get too hot, yet must be bright enough to be seen. Quality Pure colors require pure ingredients. Even trace amounts of sodium impurities (yellow-orange) are sufficient to overpower or alter other colors. Careful formulation is required so that too much
Chapter 03 Chemistry and Physics
smoke or residue doesn't mask the color. With fireworks, as with other things, cost often relates to quality. Skill of the manufacturer and date the firework was produced greatly affect the final display (or lack thereof ).
3.1 Gunpowder, one of the main ingedients in making firewors and firecrackers.
3.2 How fireworks look like when they are finished and ready to be sent to sky.
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Colors Colors, of course, are due to the chemical composition of the stars. Reds are formed from strontium (SrCO3) or lithium carbonates (Li2CO3), orange from calcium chloride (CaCl2), yellow from sodium chloride (NaCl), green from barium chloride (BaCl2), blue from copper chloride (CuCl). Every manufacturer has their own secret formulations. The explosive boom heard when watching a fireworks display is caused by the high explosive charge pushing air outward at faster than the speed of sound 340 m/s causing a sonic boom. There is a noticeable delay between seeing the explosion and hearing the explosion since light travels much faster at 300,000,000 meter per second almost a million times faster. There's a 3 second delay between the flash and the boom for every kilometer of distance you are from the exploding shell. Another funny thing about fireworks is that they appear to be two-dimensional,, unless you're right underneath them. This is because your eyes and brain can't determine which way the burning fragments of stars are moving since they're so bright against a black background.
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You've seen the chemistry and physics, where does the geology come in? Over 2/3 of the world's strontium, for example, comes from China where the strontium sulfate (SrSO4) mineral celestine, also known as celestite, is mined. Barium comes from the barium sulfate (BaSO4) mineral barite. Lithium comes from minerals like spodumene, a lithium aluminum silicate - LiAl(SiO3)2. People tend to forget that virtually all the chemical elements we use in our modern industrial society have, as their origin, minerals dug from the Earth. Science, as always, enhances our appreciation of beauty by giving us a deeper understanding of what we see and experience and how everything is connected in the world around us. Firecrackers Firecrackers are the original fireworks. In their simplest form, firecrackers consists of gunpowder wrapped in paper, with a fuse. Gunpowder consists of 75% potassium nitrate (KNO3), 15% charcoal (carbon) or sugar, and 10% sulfur. The materials will react with each other when enough heat is applied. Lighting the fuse supplies the heat to light a firecracker. The charcoal or sugar is the fuel. Potassium nitrate is the oxidizer, and
Chapter 03 Chemistry and Physics
sulfur moderates the reaction. Carbon (from the charcoal or sugar) plus oxygen (from the air and the potassium nitrate) forms carbon dioxide and energy. Potassium nitrate, sulfur, and carbon react to form nitrogen and carbon dioxide gases and potassium sulfide. The pressure from the expanding nitrogen and carbon dioxide explode the paper wrapper of a firecracker. The loud bang is the pop of the wrapper being blown apart. Sparklers A sparkler consists of a chemical mixture that is molded onto a rigid stick or wire. These chemicals often are mixed with water to form a slurry that can be coated on a wire (by dipping) or poured into a tube. Once the mixture dries, you have a sparkler. Aluminum, iron, steel, zinc or magnesium dust or flakes may be used to create the bright, shimmering sparks. An example of a simple sparkler recipe consists of potassium perchlorate and dextrin, mixed with water to coat a stick, then dipped in aluminum flakes. The metal flakes heat up until they are incandescent and shine brightly or, at a high enough temperature, actually burn. A variety of chemicals can be added to create colors. The fuel and oxidizer are
proportioned, along with the other chemicals, so that the sparkler burns slowly rather than exploding like a firecracker. Once one end of the sparkler is ignited, it burns progressively to the other end. In theory, the end of the stick or wire is suitable to support it while burning. Rockets & Aerial Shells When most people think of fireworks an aerial shell probably comes to mind. These are the fireworks that are shot into the sky to explode. Some modern fireworks are launched using compressed air as a propellent and exploded using an electronic timer. Gunpowder-based aerial shells essentially function like two-stage rockets. The first stage of an aerial shell is a tube containing gunpowder, that is lit with a fuse much like a large firecracker. The difference is that the gunpowder is used to propel the firework into the air rather than explode the tube. There is a hole at the bottom of the firework so the expanding nitrogen and carbon dioxide gases launch the firework into the sky. The second stage of the aerial shell is a package of gunpowder, more oxidizer, and colorants. The packing of the components determines the shape of the firework.
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3.3 These are diagrams showing a section picture of firework and the chemicals and materials that are used.
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Chapter 03 Chemistry and Physics
Color Red
Orange
Compound Strontium salts, Lithium salts Lithium carbonate, Li2Co3= red Strontium carbonate, SrCO3 = bright red Calcium salts Calcium chloride, CaCl2 Calcium Sulfate, CaSO4 x H2O
Gold
incandescence of iron (with carbon), charcoal, or lampblack
Yellow
Sodium salts Sodium nirate, NaNO3 cryolite, Na3AIF6
Electric White
White-hot metal, such as magnesium or aluminum Barium Choride, BaO
Green
Baruim compounds + Chlorine producer Baruim chloride, BaCl+ = brigh
Blue
Copper compounds + Chlorine producer Copper acetoarsenite (Paris Green), Cu3As2O3Cu(C2H3O2)2 Copper chloride, CuCl
Purple
mixture of strontium (red) and copper (blue) compounds
Sliver
buring aluminun, titanium or magnisium powder or flakes
3.4 A chart showing in order to get a certain color, what kind of chemical compounds needed to be put in to gunpowder.
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Chemicals in Fireworks The sights and sounds of each explosion are the result of several chemical reactions – oxidations and reductions – taking place within the firework as it ascends into the sky. Oxidizers produce the oxygen gas required to burn the mixture of reducing agents and to excite the atoms of the light-emitting compounds. Oxidizers are used in both the black powder and the stars. The most commonly used oxidizers are nitrates, chlorates, and perchlorates. The reducing agents, sulfur and carbon, combine with the oxygen from the oxidizers to produce the energy of the explosion. Oxidizers The most commonly used oxidizers are nitrates, the major component of black powder. Nitrates are composed of nitrate ions (NO3-) with metal ions. The most common oxidizer is potassium nitrate, which decomposes to potassium oxide, nitrogen gas, and oxygen gas. 2KNO3
K2O + N2 + 2.5O2
When reacting, nitrates release two of their three oxygen atoms. Because the oxidation does
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not result in the release of all available oxygen, the reaction is not as vigorous as that of other oxidizers and is more controlled. This is why nitrates are used as the major component of black powder. In fireworks their main purpose is to provide the initial thrust to power the package into the sky and to ignite each bundle of stars. Nitrates are usually not used in star explosions, because reactions of nitrates do not produce a temperature high enough to energize many of the more colorful metal salts. In the 1830s Italian fireworks makers found a group of more explosive oxidizers, which produced temperatures of 1700 to 2000°C and made possible the creation of much more intense colors. These oxidizers are the chlorates, which contain the chlorate ion (ClO3-), and they give up all their oxygen upon reaction. This results in a much more intense and spectacular reaction. 2KClO 3
2KCl + 3O2
These chlorates have the disadvantage of being less stable mechanically than nitrates, and therefore more dangerous to handle. Chlorate compounds sometimes can be detonated just by dropping them on the ground! This instability
Chapter 03 Chemistry and Physics
results from the fact that although the chlorine atom has the potential to bond with four oxygen atoms, in chlorates it bonds with only three, leaving the chlorine atom unsaturated and reactive. The complete release of its oxygen atoms makes chlorate a better oxidizing agent than nitrate. Unlike nitrate-containing compounds that produce a relatively slow burning rate, the oxidation by chlorates produces a much faster detonation an explosion. In recent years, fewer fireworks manufacturers are using chlorates. Instead, perchlorates are now more commonly used because of their increased stability and ox y ge n rel e a s e. Pe rc h l o r a t e s c on t a i n t h e perchlorate ion (ClO4-), in which each chlorine atom is bonded to four oxygen atoms. The chlorine is bonded to its maximum number of oxygen atoms, and so perchlorates are more stable than chlorates. Perchlorate is able to release all of its oxygen atoms. KClO4
and perchlorates in the star compartments immediately combines with the reducing agents to produce hot, rapidly expanding gasses. The most common reducing agents are sulfur and carbon (charcoal) –standard components of black powder – which react with oxygen to produce sulfur dioxide and carbon dioxide respectively. O2 + S
SO2
O2 + C
CO2
KCl + 2O2
So, perchlorates are not only more stable, but more oxygen-rich than chlorates. Like chlorates, produce more vigorous reactions than nitrates. The oxygen released by nitrates, chlorates,
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Physics of Fireworks Most people don't realize the vast world of physics that takes place during every fireworks show. The science of pyrotechnics involves many physics applications that must be considered to produce entertaining displays. Pyrotechnicicans must take into account the relationships between vectors, velocities, projectiles and their trajectories, the explosion forces behind burst patterns. Physics of aerial shell fireworks These are the type of fireworks that are used at most Fourth of July or sporting event shows. Aerial shells contain the chemicals that when ignited, produce the brilliant flash of colored light. These shells are loaded into mortars, which are basically just small cannons , and are fired into the sky. To the right you can see a table that lists all commonly used shell sizes and their corresponding initial mortar velocities. These velocities are the speeds that the shells are traveling as they are fired out of the mortar. The 2“ through 6" shells are used at almost all fireworks shows and are used almost exclusively at small shows. The 8", 10", and 12" shell sizes are usually used at only
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large fireworks shows as they are more expensive than the smaller sizes. The 24" and 36" shell sizes are even more expensive because they produce extremely large burst patterns. These monstrous aerial shells are only used at the largest shows and during special circumstances. As you can see in the table, larger shell sizes produce greater initial mortar velocities. This happens because the larger mortars used to fire larger shells have the capacity to house greater amounts of blackpowder/pyrex used to propel the shells out of the mortar. Greater amounts of blackpowder/pyrex, when burned, produce more excess gases than do smaller amounts. These larger amounts of excess gases cause the shell to be pushed or propelled out of the mortar faster, resulting in greater initial velocities. The greater initial velocities produced by larger shells result in the shell attaining a greater height before it explodes and emits its bright flash of light. Shells usually travel about 100 feet vertically for every inch they are in diameter; depending on the angle they are fired from.
Chapter 03 Chemistry and Physics
Mathematics The relationships between the initial velocities and the distances traveled by the shells can be understood and manipulated by using the following formulas and mathematical methods:
Initial Shell Velocities Shell Size (inch)
Initial Velocity (ft/sec)
2 inches
117.5
Y=VyT+0.5GT^2
3 inches
144
Y=vertical height, Vy=initial vertical velocity, T=hang time, G=acceleration due to gravity X=VxT
4 inches
166
5 inches
186
X=horizontal distance, Vx=initial horizontal velocity, T=hang time The Pythagorean Theorem - a^2 + b^2 = c^2
6 inches
203.5
8 inches
235
10 inches
263
12 inches
287.5
24 inches
393
36 inches
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a or b = vertical or horizontal velocity, c=resultant initial velocity The Trigonometric Functions - sine, cosine, and tangent In a right triangle sine=opposite side/ hypotenuse, cosine=adjacent side/hypotenuse, tangent=opposite side/adjacent side
3.5 The form on right shows the relationship between shell size and initial velocity.
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1200 1100 1000 900 800 700 600 500 400 300 200 100 0
3.6
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100
200
300
400
500
600
700
800
75 degrees Fireworks that range from 2" to 12" shell Trajectories Fired at 75 Degrees. The first two formulas you see are primarily used to chart trajectories like in the graph on the left that shows the flight paths of 2" through 12" shells fired at 75 degrees. These graphs are very useful tools that allow pyrotechnicians to visualize how high and how far their shells will travel during a show. This information can be used to aid the process of choreographing the show to music, and determining if some shells will exceed the safe zone for that particular site. The Pythagorean Theorem is used to find a certain initial velocity value if the other two are known. This is helpful in determining information needed for the other formulas. The Trigonometric Functions are also used to find initial velocity values, but are used to find vertical heights, horizontal distances, and firing angles as well. Pyrotechnicians use these mathematical methods along with charts, graphs, and computer programs derived from them to Pyrotechnicians must also consider shell burst sizes when planning shows. They must know how big certain bursts are when compared to others so that the choreographing of the show is
Chapter 03 Chemistry and Physics
in sync and so they don't exceed their safe zone requirements. As with initial mortar velocities, the bigger the shell size the larger the effect. It follows the same principle in that larger shells contain greater amounts of chemicals that when ignited produce greater explosion forces than do smaller shells. This results in varied burst sizes. Shell burst sizes are usually about 45 feet in diameter for every inch in shell size, depending on how tightly the shell is packed. As you can see in the diagram on the right, the differences in burst sizes can be extremely huge. It is just one more thing that pyrotechnicians must take into account to produce entertaining and attractive fireworks shows.
360 ft
90 ft
2 inch burst shell 8 inch burst shell
3.7
Sulfur, charcoal, and potassium nitrate Charcoal, in this case, is not the briquettes you use on your grill, which often contain no actual charcoal, but is the carbon residue left behind by organic matter (like wood) once it has been charred (or pyrolyzed), and all the water removed. Potassium nitrate is found in sources like bird droppings or bat guano. Take a mortar and pestle, mix them together, and what you’ll get is a fine, black powder. Gunpowder, in fact. All you need now is some oxygen — readily found in our atmosphere the potassium nitrate source and a small source of heat. (A match will do.) Put it all together, you’ll get an explosion (and a loud boom), but that’s hardly a firework! After all, if you’ve ever seen one, you know that the four major things that make a good firework are height, size, shape and color. The way you launch a firework is basically the same way you launch a cannonball out of a cannon! You put a “lift charge” in between the actual firework and the bottom of a strong, closed tube or pipe, and ignite it, propelling the firework up. How high you want it to go is dependent only on the initial velocity of your firework, which is almost always larger for bigger fireworks.
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A small fireworks show might have 2" (5 cm) to 6" (15 cm) diameter shells being launched, which reach a height of anywhere from 200 to maybe 500 feet (60-150 m). But a very large fireworks show, like the one in New York City, uses fireworks with shells up to two or three feet in diameter (up to nearly a meter), and those fireworks often reach altitudes of well over 1,000 feet (300 meters). Once the initial launch happens, the fuse on the actual firework itself — if all goes properly — is now lit, and burns as it goes up. For aesthetic and safety reasons, you launch the larger fireworks to a higher altitude. The physics helps out tremendously with the size of your fireworks as well, because a larger firework requires a larger lift charge! And the amount of the lift charge that you use is sufficient to launch it to the necessary altitudes described above, which is why larger fireworks get launched to higher altitudes. So long as they’re not “duds” (i.e., so long as the fuse ignites and burns properly), they will explode at or near the apex of their flight. The higher ones are usually larger, resulting in, well, aestheticallypleasing (and again, safer) fireworks displays. But
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what determines their spectacular shapes that they come in? To find that out, we need to go inside the anatomy of a firework. (see graph 2.6). Fireworks come in many different styles, but the two important elements, once your firework has been launched into the air with its fuse lit, are the burst charge and the stars. The burst charge can be as simple as more gunpowder, or it could be a more complicated (or even a multi-stage) explosive. The stars, on the other hand, are what actually go off in many directions, producing the beautiful display. When the fuse burns down to the point where it reaches the burst charge, it ignites! This ignition, depending on how the firework is put together in the first place, will send the stars off into whatever pattern or direction it was designed for. It will also reach high enough temperatures to ignite the individual stars. This is where — for me — the most interesting part of the fireworks happens. In addition to whatever propulsion or fuel exists inside these stars, such as the ability to make them spin, rise, or thrust in a random direction, the stars are also the source of the light and color we find in our fireworks.
Chapter 03 Chemistry and Physics
2-Break Color and Report Shell Time Fuse Burst Charge Stars Intermediate Fuse Passfire Report Comp. Lift Charge
American Cylinder Shell Time Fuse Burst Charge Stars Passfire
Lift Charge
How are these “stars” responsible for color? Although there are some recent advances (covered in excellent detail by Janet), the simplest explanation is that different elements and compounds have different characteristic emission lines. For example, if you take some sodium and heat it up, it emits a characteristic yellow glow, because of its two very narrow emission lines at 588 and 589 nanometers. Well, we have a great variety of elements and compounds that emit a great variety of colors! Different compounds of Barium, Sodium, Copper and Strontium can produce colors covering a huge range of the visible spectrum, as shown below in chromaticity space. And that ’s how fireworks work, from launch, up to the proper height, to their explosion, to the size, pattern, and color of the spectacular show they put on!
Oriental Style Shell Burst Charge Stars
Time Fuse Lift Charge
3.8
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Fighting Gravity Gravity is the force that keeps ever ything attached to the Earth. Without it, we'd all float off into space. Those high-flying fireworks need to overcome the force of gravity, and the people who make fireworks and stage shows use a precise amount of fuel to ensure that fireworks explode safely overhead, rather than on the ground. The displays seen at public events use fireworks with at least two elements. One is a shell that explodes in colors or crackles. The other is a small rocket engine. To launch fireworks into the air, they're loaded into metal or cardboard tubes. When the fuse is lit, materials in the rocket part of the shell burn very quickly. If these materials were spread out on the ground, they'd burn up immediately in a flash, wouldn't be very exciting. Because they're burning in a confined space, the launch tube, the rocket engine builds pressure beneath it, which is known as thrust. So much energy builds up that the firework lifts out of the tube and into the sky. Once it's there, inertia, or the tendency of an object to keep moving, works with the rocket engine to keep it flying higher. A separate fuse inside the firework ignites the shell when it reaches the top of its trajectory.
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Eventually, gravity pulls the ash and the remnants of the shell back to Earth. Creating Different Shapes A chrysanthemum shell is one of the simplest fireworks to make, because it operates on a simple rule of physics: explosive force travels equally in all directions from the point of ignition. In other words, if something blows up in the air, where there's little resistance, it will create a sphere. If that same explosion took place on the ground, you'd wind up with a dome-shaped blast, since objects in motion will travel farther if there's little resistance. You would still have a crater at the site of the blast, but most of the energy would reflect upward. Fireworks makers use the laws of physics to create the different shapes that we see during displays. A chrysanthemum has a weak outer wrapper that blows apart in all directions, creating a sphere. Palms, which are larger on the top, are held in reinforced tubes that push most of the blast to the top, creating an effect that looks like a palm tree in the sky.
Chapter 03 Chemistry and Physics
A Hole World of Difference Most people are familiar with Jumping Jacks and firecrackers. These are the small fireworks that people buy for backyard Fourth of July celebrations. If you put a Jumping Jack next to a firecracker, they look almost identical. Both are small, tightly wrapped tubes of paper with a fuse in one end and flammable powder inside. When you light a firecracker, you get a loud bang. When you light a Jumping Jack, it spins and bounces on the ground and occasionally takes off into the air. Why does this happen? Look closely at that Jumping Jack and you'll see a tiny hole punched into one end. This it what causes it to move around. When the powder inside ignites, it creates a tiny jet of flame that propels the firework across the ground. The location of the hole near the bottom, coupled with the light weight of the firework, causes it to bounce in a rotating, triangular pattern. The firecracker doesn't have a hole, so there's no place for energy and heat to escape when its powder burns. The pressure builds up inside the firecracker until it explodes with a loud bang. When matter changes from one state to another,
it releases gases and energy. If these gases and energy do not have a way to safely disperse, the result is an explosion.
3.7 Professional fireworks are launched out of mortars unlike bottle rockets which use sticks as shown above
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Summary To launch of fireworks shell, you first have to light the fuse. Fuses for fireworks are generally formed from cords with a black powder core. They burn at a controlled rate and are used to ignite the shell's slow-burning black powder propellant - a combination of 75% saltpeter (potassium nitrate or KNO3), 15% charcoal (basically C), and 10% sulfur (S). Black powder has been around a long time and was invented back in 7th century China. It's a “low” explosive that burns at slower subsonic speeds rather than the fast detonation of “high” explosives making it ideal as a propellant. The charcoal in black powder acts as a fuel, the sulfur increases the rate of combustion by lowering the temperature of ignition of the mixture, and the saltpeter breaks down to provide the oxygen necessary for combustion (4KNO3 = 2K2O + 2N2 + 5O2). As the shell ascends, a time-delay fuse is still burning toward the upper compartment of the shell where the “stars” are located. The stars are 3-4 mm clay-like masses which contain the chemicals necessary for the pyrotechnics show when the shell explodes from its charge of high explosives.
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It's all a matter of timing. You want the fireworks to explode at the apex of the shell's climb. The high explosive charge ignites the stars and tosses them outward. The packing of the explosive and the stars determines the type of effectthe spherical peony or chrysanthemum, the expanding ring, the drooping willow, etc. There's a whole art and science behind the packing of fireworks shells with different configurations, formulations, and shapes. Colors, of course, are due to the chemical composition of the stars. Reds are formed from strontium (SrCO3) or lithium carbonates (Li2CO3), orange from calcium chloride (CaCl2), yellow from sodium chloride (NaCl), green from barium chloride (BaCl2), blue from copper chloride (CuCl), etc. Every manufacturer has their own secret formulations. The explosive boom heard when watching a fireworks display is caused by the high explosive charge pushing air outward at faster than the speed of sound (340 m/s) causing a sonic boom. There is a noticeable delay between seeing the explosion and hearing the explosion since light travels much faster at 300,000,000 m/s (almost a million times faster!). There's a 3 second delay between the flash and
Chapter 03 Chemistry and Physics
the boom for every kilometer of distance you are from the exploding shell. Another funny thing about fireworks is that they appear to be two-dimensional, like they're being displayed on a flat screen, unless you're right underneath them. This is because your eyes and brain can't determine which way the burning fragments of stars are moving since they're so bright against a black background. You've seen the chemistry and physics, where does the geology come in? Over 2/3 of the world's strontium, for example, comes from China where the strontium sulfate (SrSO4) mineral celestine, also known as celestite, is mined. Barium comes from the barium sulfate (BaSO4) mineral barite. Lithium comes from minerals like spodumene, a lithium aluminum silicate - LiAl(SiO3)2. People tend to forget that virtually all the chemical elements we use in our modern industrial society have, as their origin, minerals dug from the Earth.
A 6" fireworks shell. Fuse is at left, black cubes are the “stars", a gray explosive charge is to the right, and the black powder propellant is at the far right. All encased in a cardboard shell.
Setting up the mortars and shells for a show
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Part II “Life is a like a firework lit sky, but without the sparks that sometimes might end up burning you, but without those burns life is nothing but darkness�
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“Unfamiliar guests, excited children, strange decorations, noise from party poppers, fireworks or balloons and family disputes can often make the most settled animals ill at ease in their usually familiar surroundings.�
Start
First: Shell parts
There are many types of fireworks, where one of the most common in firework displays is the aerial shell. The aerial shell is used in fireworks displays, and can be either a round or a cylindrical shape. These aerial shells are loaded into tubes, called “mortars." Once lit, the aerial shell will fly into the air and once the aerial shell is at the higest point (apogee), it will explode and shoot pyrotechnic stars in all directions. In this instructable I will be talking about the procedure of assembling a round aerial shell. Note: I do NOT recommend the average person to try this! This will be illegal to do without licensence in many cases, it is on your own response wether you do this legally or not. When working with fireworks it is very important to use proper safety gear while making. It is recommended to wear faceshield or safety goggles during the making. While making the shell, one should do it away from heat souces, such as candles, cigarettes, stoves etc.
Shell hemispheres You will need two 3" paper hemispheres to make this shell. Note that the hemispheres themself are actually not 3", but smaller, since there must be room for pasting and quick match to make the shell fit in the 3" mortar tube.
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Stars A batch of 75 grams of 10 mm pumped “Tiger tail" stars were made for this shell, however only 70 grams were used. Remember always to make more than you need. It's better to have a bit more, than be needing. The stars were primed in meal black powder to ensure ignition. Since Tiger tail stars ignite easy, you might find that this might be unnecessary. If a 'rising comet' is desired, a 20 mm or 3/4" comet is pumped with the compostion. Make sure that the comet has a burn time equal to the time fuse or spolette (3 seconds). Tiger tail stars: Potassium nitrate. Charcoal (Pine airfloat) Sulphur SGRS or Dextrin
44 44 06 06
Chapter 04 DIY Fireworks
is needed to paste the strips to the shell. Wheat paste is a cheap solution that works well. Lift charge A lift charge is needed to shoot the shell out of the mortar. Approximately 15 grams of good granulated or corned black powder works well. More or less be used depending on the quality.
4.1 These are the rough materials that you will be needing to create fireworks
Bursting charge 'Meal coated rice hulls' was used in this shell Time fuse A 'spolette' is a small tube, where black powder is confined in it. This will act as a time fuse. Pasting 30-40 lbs kraft paper in ~70x15 mm strips are used for pasting the shell using the 3-strip pasting method. If another pasting method is desired, the strips might have to be longer or wider. A glue
Ignition For igniting the shell either a piece of visco fuse and quick match or shoothing-wire and an e-match can be used. In this tutorial a piece of shooting wire and e-match was used. Note with this way you will need a power supply, and that you can not light the shell with a lighter. Other You will also need lifting cup, paper tape, scissors, drill, gummed paper tape kraft paper, tissue paper, brush, hot melt glue gun, cotton twine and string.
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Second: Shell Construction Start by drilling a hole in the pole of one of the paper hemispheres. The diameter of the hole must be the same as the diameter of the time fuse or spolette. Insert the time fuse or spolette about half way in the hole, and hot glue it on both sides. Make absolutely sure that there are no air holes, this will likely result in a flower pot. Place each hemisphere on a stand, which can simply be made out of an empty toilet roll cut in half. This will prevent the hemispheres from rolling around when you are filling them.
Third: Filling with stars or burst and closing Arrangethe stars around the wall of the hemispheres to the rim. The stars should be sticking a bit over the rim. If the shell is underfilled it will result in a visible area of no stars when the shell is launched. Next cut two pieces of tissue paper, one of them with a hole to go over the time fuse or spolette. Put the pieces in each hemispheres against the stars and fill tighly with burst charge to the rim. A bit of “booster", such as whistle mix or flash
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4.2 The pictures on the top shows the detail steps of shell construction.
Chapter 04 DIY Fireworks
powder is added in the center of each hemisphere and spread loosely in the burst charge with fingers. Not much should be used, maximum 1g. Quickly snap the two shell hemispheres together. This is not as hard as it sounds like, but if done too slowly, the stars or burst charge might rearrange or fall out, and the previous steps will need to be repeated. If the rim each paper hemisphere touch eachother at this point, the shell is underfilled. However if done correctly there should be a small gap of around 1 cm at equator. Place the shell on the stand time fuseside down, and use a wooden dowel to gently hit the upper hemisphere on different places. The stars will then arrange inside the shell and hopefully the two hemispheres will reach eachother. Seal up around the equator with masking tape to close the shell temporarily. Also put a piece of masking tape around the end of the time fuse or spolette to protect it from being damaged during the next steps
4.3 The picture on the top shows the detail steps of Filling with stars/burst and closing
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Fourth: Pasting the shell The next step is pasting the shell, which is the hardest and most time-consuming part of round shells. The pasting method descriped here is the socalled 3-strip pasting method. Unlike the “normal" pasting method (pasting strips with a length of half the equator around the shell) the 3-strip pasting method does not “build up" near poles. To make your pasting strips sticky before you paste you will need to add a glue to each 70x15 mm kraft paper strip on one side. This can be done quickly by arranging some strips on a wide wooden board. Next apply a thin, even layer of wheat paste with a brush. These strips are now ready for pasting, but you will need to repeat this step many times, since you will need a lot of strips to complete your shell. The shell is pasted as showed on the picture. A strip is pasted from the “northpole" pointing towards the “southpole". Then a strip beside is pasted from the “southpole" pointing towards the “northpole". A strip is then pasted between these two strip. This pattern is continuously pasted around the shell. Press out the airbubbles under the strips, this will result in a nice-looking shell.
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Everytime you finish a way around the shell (layer) make sure to write on the shell how many layers you have pasted so far, you might forget it. When finished pasting the shell, multiply the layernumber by two, since each layer with this pasting method counts for two actual layers. While pasting the shell, cut a ~8 cm piece of cotton twine and make a loop on it. Hot glue it to the top of the shell (the opposite hemispheres of the one with the time fuse in it) and paste like before, just making the strip covering the twine. This shell needed 10 layers of pasting (=20 layers) to complete. The ideal is to make the shell ~5 mm smaller than the mortar tube, in this case the OD of the shell should be ~7 cm. Making it this diameter might take hours for beginners to complete. After the layers of pasting, let the shell dry completely.
Chapter 04 DIY Fireworks
Fifth: Lifting charge Peel of the making tape that protected the time fuse. Cut two lengths of black match and bend them over the exposed end of the time fuse. Wrap a line of string numerous of time around the black match to secure them to the time fuse. Then either secure the string with a dot of hot glue or tie a knot. The black match will be a prime for the time fuse and make it easier to ignite. Without it the time fuse might fail to ignite and make it a dud shell. The next step is the lift. Take your desired lifting cup and poke a hole in the bottom, big enough to put the quick match or shooting wire through. The quick match or shooting wire should be long enough, so that when the shell is loaded in the mortar, there will stick a bit out of the mortar. If you use quick match insert a piece of visco fuse it. This will be the delay between when the shell is ignited, till it shoots out of the mortar. Next put the quick match (not the visco fuse end) or shooting wire through the hole punched in the lifting cup. If using quick match, tear a bit of the paper off the end, so that the black match will be exposed. If using shooting wire, attatch your e-match. Next slide the quick match or 4.4 The picture on the top shows the detail steps of pasting the shell.
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shooting wire back, so it centres in the middle of the lifting cup. Secure the hole with a bit of hot glue or gummed paper. Add you lift charge in the lifting cup, in this example 15.3 grams of pulverone was used. The amount used all depends on the quality of your black powder. The rule of thumb is to use approximately 1/10 lift of the shells weight. The shell's final weight (everything included) was around 150 grams.
4.5 The picture on the rigth shows the detail steps of lifting charges.
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Chapter 04 DIY Fireworks
Sixth: Almost done... Attach the lifting cup to the shell. The time fuse should be pointed directly down the lifting cup and the quick match or shooting wire should be put inside the loop on the top of the shell. Add a line of hot glue around to secure the lifting cup. Cut either a strip of gummed paper or kraft paper. The strip should be long enough to fit all the way around the lifting cup plus a little more. Cut the strip halfway all the way down with a distance of ~1" as shown on the picture. If you're using gummed paper activate it with water, if using kraft paper, brush with layer of wheat paste. Wrap the uncut part around the lifting cup and the cut part around the shell as shown on the picture. Make everything as tight as possible. If you want to add a rising comet to your shell, attach it the same way as the lifting cup was attached: Cutted-up strip with glue and hot glue. About 2 mm of the comet should be exposed to ensure ignition.
4.6 The picture on the rigth shows the detail steps of setting up an almost finished shell.
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Seventh: Finished The shell is now finished. It is a good idea to attach label in case you keep the shell over a longer time, so you will know what type of shell it is, which stars, amount of lift etc. The shell can now be fired, but please note that this is obiously the most dangerous part of it all, so proper safety gear must be used. First of all your eyes, fingers and ears are the most important thing to protect. Wear safety goggles/face shield, firepro of gloves and ear plugs/ earmuffs during firing (as a minimum.) When firing, you can either use a mortar stand to hold your mortar tube if you have one, or you can bury the mortar tube in the ground about 2/3. Next the shell is loaded to the tube with the quick match or shooting wire sticking out the shell should fall freely, without any help to make it reach the bottom. Also please take care of your surroundings: The shell should be fired a long distance away from people, houses and flammable objects. Run a good long distance after igniting the fuse. If you want to film the shell, it is recommended to be at least two persons: one will be filming, the other will ignite the fuse. If the shell should somehow fail to lift properly
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and explode on the ground, you will be glad you did wear safety gear. Sometimes a “flower pot" happens (mainly if the shell is not sealed well around the time fuse, or if the spolette is not rammed solid enough), which is simply the shell explodes in the mortar, shooting stars into the sky. The mortar may or may not fracture when this happens, but this is where burying the mortar comes in handy: the surroundings of the mortar will arbsorb most of the shock, and the fragments may not fly very far.
Chapter 04 DIY Fireworks
4.7 Finished shell
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“Whether you’re celebrating Independence Day, Guy Fawkes Day, or Diwali, it's always tempting to take pictures of the fireworks exploding in air. After all, a good firework show is an amazing spectacle, and you've probably got a camera on you anyway. Unfortunately photographs of fireworks usually don't hold a candle to the real thing. If you're tired of your festive pictures coming out grainy, blurry, underexposed or overexposed, read on.”
In this chapter you will know how to photograph fireworks in a professionial way where you have your camera and everything set up and an easy way, photographing from your smartphone!
In order to create a professional image you will need: A camera that you are familliar with Tripot (Recommended) First Change your approach from treating light as illumination to treating it as subject. This requires a different way of thinking about how you use the camera because fireworks create their own exposure. In order to preserve color and shape, you will have to be prepared to vary the exposure and to account for other elements such as smoke from fireworks, or building lights in the background. Knowing how to focus the camera properly is also going to be important because passive autofocus systems cannot manage in darkness or low light situations, so be prepared to go beyond the simple point and click. A fireworks show involves many, many fireworks, so be ready to experiment, preferably with a digital camera so you get instant feedback. Since
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fireworks produce basically monochromatic light (from chemicals), their colors will be distinct at a variety of apertures and ISO settings. A long exposure is required to let a few fireworks trace out their patterns. Different aperture and ISO settings will affect the brightness of the surroundings – bright surroundings are distracting, but subdued rather than completely black surroundings are much more interesting. Choose the amount of foreground and sides to include with this in mind. (The aperture setting isn't very important for depth of field with far away fireworks, since they'll be essentially at infinity, and any foreground should be dim and indistinct in any event – it mainly matters for overall exposure, and a relatively wide aperture and low ISO will give less “noise" than a small aperture and high ISO.) Second Get a good position and try to determine approximately where the fireworks will be bursting and get a spot with an unobstructed view of that area. If the fireworks are popular, you'll need to show up early to get a good spot. Figure out the wind direction and get upwind of the fireworks so that your shots aren't obscured
Chapter 05 Photographing Fireworks
Don't extend the legs or center column of the tripod. Keep everything close to the ground to keep the camera as steady as possible. A flashlight can be used to fill in shadows. Ensure that wherever the tripod is set up is safely out of the way of other people tripping over it. If you're in a crowd, ask a friend to act as a shield to ensure other people don't walk into your camera shooting while you're looking upward. by smoke blowing toward you. Find a spot where you can avoid getting a lot of extraneous ambient light in the picture, as this will cause an overexposure. When scouting out your location, choose some interesting features to serve as the background. This will make your photos more exciting for others to view. Third Set the camera on the tripod. Fireworks generally accompany celebrations, so it's not surprising if your memories of them are a little blurry. Your pictures, however, should be crisp and clear. Photographing fireworks requires long exposure times, so a tripod is your most important ally. No matter how steady your hand is, it's not steady enough.
Fourth Ensure the camera settings are correct. While some digital cameras have a “fireworks mode", where you don't have to worry about the settings, knowing how to fix the settings to work to the best advantage for taking great shots of fireworks is essential. It's best to set these well ahead of time, as it may be difficult to see your camera controls or your checklist in the dusk or dark. Double checking before you set off the take the photos is a good way to get used to changing the camera settings and knowing the limitations of your camera. The changes that you need to consider making to the settings include: Set the focus to infinity. You're generally far enough away from fireworks that you can adjust the lens focus to infinity and leave it there. If you
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want to get a closeup of a small part of the burst, you may need to adjust the focus as you zoom in. If you want to include buildings or people in the background, you may want to bring these into focus. Avoid the use of auto focus if possible; as already noted, most cameras have difficulty adjusting focus in low light conditions. Use a smaller aperture. Set the aperture in the f5.6 to f16 range. F8 is usually a good bet, but if you're shooting with ISO 200 film you may want to kick it up to f16. Turn off the flash. The fireworks are bright enough, and your flash wouldn't effectively reach them anyway; however, it will dull the atmosphere of the shot, thereby lessening its impact. Take off any filters or lens caps before shooting. (see 5.4 on right) If your lens has IS (Canon) or VR (Nikon), turn it off before shooting. If you are shooting with an SLR or DSLR camera, chances are your lens has the IS (image stabilization) or VR (vibration reduction) feature built in. And if you have IS or VR (it is essentially the same thing, but Canon and Nikon just had to label it differently), then chances are you are used to leaving it on close to 100 percent of the time -
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which is generally a good idea. IS/VR is meant to sense the vibration (the shaking of your hands, mostly) and compensate for it. When it does not sense any, it creates it. Turn it off in order to get sharper images. Fifth Frame the picture before shooting Look through the viewfinder during the first few bursts and figure out where the action is. Point your camera at that spot and leave it there. You don't want to be looking through the viewfinder while you're trying to shoot, because you’ll likely shake the camera or your timing will be off. If you're trying to get closeups, of course, your framing will need to be more exact and you'll probably have to play with it more. Once again, frame carefully to exclude other light sources that might distract from the fireworks or cause your photos to be overexposed.
Chapter 05 Photographing Fireworks
5.1
5.3
5.2
5.4
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Sixth Keep the shutter open to capture the entire burst. Despite what it may feel to you, provided the sky is very black, leaving the shutter open won't result in overexposure. Set the exposure to the maximum length. To get the sharpest image it is best that nothing comes in contact with the camera during the exposure. Use the automatic long exposure of 30 seconds or more. If your camera does not have an automatic long exposure the use of a cable release is okay. Use the BULB (B) setting, which will keep the shutter open as long as the button is depressed. A rule of thumb is to open the shutter as soon as you hear or see the rocket shooting into the sky and to leave it open until the burst is dissipating. This will usually take several seconds.
5.5 To capture the best effects from bursts, exposure times will usually be about half a second and four seconds but judge it as you see it. For ISO 100, photography experts recommend trying 4 seconds at f5.
5.6 When taking a reading for exposure, don't point the camera at the center of the light source; if you do, the shot risks being underexposed and the trails of light will be faint. Instead, experiment with a range of shutter speeds and bracket the exposure.
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Chapter 05 Photographing Fireworks
To use auto focus in the dark of night, try to first take a picture of lights on the horizon. Then when you set off the next exposure into the pitch black of night the lens will already be set at infinity. Also, try starting the long exposure when there is a large fireworks burst. The auto focus may work on this pattern and therefore ensure that a subsequent burst during the exposure will be in focus too. Seventh Spice it up Even good pictures of fireworks can be boring if there's nothing to distinguish them. You can make more interesting photos by including buildings in the background or spectators in the foreground. Choose your shooting location to try to get an unusual and unique perspective on the show if possible. Ensure that the camera is stable on its tripod and that the focal length and frame is right for the height of the fireworks. For a wide angled shot of fireworks in a setting such as a well lighted cityscape, judge the height of the first few fireworks bursts and use that as a reference for framing the whole scene. Vary the exposure times set on your tripodlocked camera so that it captures both single and multiple fireworks bursts.
Smartphones They can be tricky to photograph with a regular camera. It’s even harder with an iPhone camera. If you’re going to be shooting fireworks over the next couple of days, here are some tips to help you get the best shots possible using your iPhone First, a little background on why it’s so hard to photograph fireworks. You’re shooting fireworks in extremely low light situations, almost dark. The iPhone’s camera and lens isn’t really optimized to shoot in situations that dark. The camera will automatically adjust to a fast ISO rate. This makes the camera more sensitive to light but it can potentially make your photos
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look noisy and grainy. It will also adjust to a slow shutter speed, making it more difficult to get sharp photographs without a tripod, but you will get some cool light trails in your photos. Creating picture using an app First Use a tripod or steady yourself and your iPhone. Even on the newest iPhones, the shutter will probably be open longer than normal. Without a tripod, any movement at all, even the slightest, could mean blurry photos. you can mount your iPhone to a tripod using a Glif mount, a DiffCase, or many other options. The Hipstamatic iPhone case even has a standard tripod mount. Second Turn off your flash All it will do is bounce light back from anything that’s near you and cause unwanted light anomalies in your photo. Third Use a separate exposure lock. One of the third-party camera replacements with separate focus and exposure lock,such as ProCamera, Camera Genius, Camera+ or the free Camera Awesome. Lock the focus to infinity (or distance).
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Lock the exposure to the fireworks. The focus and exposure will probably stay locked for several shots. Locking the exposure on the fireworks will help hold the color and help prevent the colors of the fireworks from blowing out in your photos. Fourth Use a self timer set to about half a second. This gives the camera a tiny bit of time to steady after releasing the shutter. All of the camera replacement apps mentioned have self-timers. Fifth Go easy on the digital zoom Resist the temptation to use it at all. If you have to, don’t use it very much — not more than 2x. The more you zoom, the more your iPhone camera is susceptible to movement and the greater the chance your images will show blur. Get as close as you can and then crop your images down. Sixth Try one of the long-exposure, low-light cameras for effect. Camera apps 645 PRO and NightCap both have better low light capabilities by allowing the iPhone’s shutter to stay open as long as 1 second. Not only does this help bring out and hold the colors of the fireworks, but you can also get some great light trails shots.
Chapter 05 Photographing Fireworks
Seventh Take lots of pictures. Fireworks photography on an iPhone is hit-or-miss. In my experience, it’s mostly miss. Take a lot of photos. Most of them won’t come out well. The more photos you take increases the odds of getting more usable fireworks photos.
Creating a digital wallpaper. Have you ever wanted to film the whole entire firework show and take pictures? You certainly can do it with only one smartphone! Film the firewok show first and afterwards when you are going over the video just pause and take a screenshot whenever you found a scean that you really like and enjoy! Those screenshot photos will be a great wall paper for your smartphone.
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Selected Bibliography Culinary works for a general audience can not accommodate the sort of referance apparatus that one experts in works of scholarships - a drawback, perhaps, in a history book that starys as far into polemicalterritory as this one. Readersinterested in finding out more about fireworks and its history will find paths to further learning in the works listed below. I will be happy to direct people frustrated by the absence of documentation for particular factual claimsto speific resources; please write me at vchang@cca.edu. Internet resources A great deal of informationis now avalable online along with even grater amount of misinformation, politicking, and rumormongering. Some sites that may be interest to readers of this book. Most of the images are found in google images http://www.examiner.com/article/the-history-of-fireworks-america-and-before http://library.thinkquest.org/15384/history/ http://en.wikipedia.org/wiki/Fireworks#History https://www.princeton.edu/~achaney/tmve/wiki100k/docs/Fireworks.html http://wallpaperfocus.com/fireworks-cool-wallpapers-hd-1920x1080.html http://www.pageresource.com/wallpapers/1891/pretty-fireworks-yvt-hd-wallpaper.html http://www.dailydot.com/lol/how-to-make-fireworks-videos/ http://paleofuture.gizmodo.com/diy-fireworks-instructions-from-the-1920s-were-ridiculo-655920764
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Bibliography and Index
A absent 23,25,55 acceleration 67, 54 acre 12, 15, 18 adult 87, 45, 23 alto 17, 34, 67 anode 56, 23, 45 answer 9, 31 ante 1,64, 86 anterior 4, 7, 90 are 19, 32, 89 area 9, 34, 89,90 atto- 33, 45, 88 author 23, 45, 90
B bachelor 52 bacillus 34, 67, 90 back 20, 24, 90 bag 76, 87 bale 1, 7, 89 bass 4, 67, 24, 57 basso 89 bat 16, 19, 60 BaumĂŠ 45, 59 before 12, 45, 67
Bible 67, 87,88 billion 23, 45, 78 bishop 5, 7, 90 black 26, 48, 90 bolivar 34, 70 book 34, 45, 88 born 12, 56 bottom 6 brick 51 brightness 50
C anceled 30 candle 13, 56, 90 carat 34, 67 catcher 20, 89 cent 40, 78 centavo 21 centi- 45, 90 centime 1, 9
D date 20, 67 daughter 33, 56 day 21, 87
E earth 30 eastern 78 edge 34, 57 eldest 12, 56, 90 ell 18, 19 empty 20 end 13, 16 energy 89 erg 33 excellent 25, 78
F failure 89 false 27, 39 family 12, 90 fireworks 1, 4, 7, 9
H half 45, 90 harbor 23, 56, 67 hard; hardness 90 hect-; hecto- 13, 19 height 29, 34, 59 high 43, 54, 65
hit 23, 65, 76 horse 21, 32, 43, 54 hour 10, 32, 45, 56 humidity 22, 45, 65 hundred 12, 34, 56 husband 89
J jumper 89
M minute 16 molal; molality 17 mole 18 month 19 moon 20 morning 21 muscle 67
N noon 8, 54 normal 9, 21 north; northern 10 note 11, 34 noun 78
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O ocean 2, 34, 90 ohm 3, 34, 67 old 4, 54 order 5, 56 over 12, 34
P pater 7, 9 pawn 8, 78 pence; penny 9 per 10, 14 peseta 11, 34 peso 12, 19 petite 13, 56 piano 14, 45 pico- 15, 78 pint 16, 45 pipe 17, 35 pitch 18 72 pole 19, 92 port 20, 89
Q quart 2, 45, 67
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quartile 3, 57 quarto 4, 82, 83 queen 5, 12 query 6, 34, 45 question 7, 89 quetzal 8, 12 quire 9, 49
R Reaumur 23, 66 recipe 90
V vector 2, 56 velocity 67 verse 89, 13 verso 34, 56 versus 89
W weight 45, 82 white 12, 15 wicket 84, 90
Y yard 78, 90 year 15, 67
Z zero 35, 56 zone 12, 79
This book was designed by Vivian Chang. It was editied and set into type in U.S. and printed and bound by Key in San Francisco. The type faces use for body text is Adobe Caslon Pro, designed by William Caslon and Univers designed by Adrian Frutigeris is used for subheads and fireworks' descriptions. The paper is Glatfeleter Laid.