88 résultats pour "carried"
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From Bulfinch's Mythology: Theseus - anthology.
One of the most celebrated of the adventures of Theseus is his expedition against the Amazons. He assailed them before they had recovered from the attack ofHercules, and carried off their queen Antiope. The Amazons in their turn invaded the country of Athens and penetrated into the city itself; and the final battle inwhich Theseus overcame them was fought in the very midst of the city. This battle was one of the favourite subjects of the ancient sculptors, and is commemorated inseveral works of...
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Ship.
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INTRODUCTION
Ship, vessel that is buoyant in the water and used
B1 Biremes Experience soon proved that longer ships posed a new set of problems: They were weaker structurally, more difficult to maneuver, and presented a larger target to anyenemy ship with a ram. In the 8th century BC Mediterranean shipbuilders eliminated these problems with the bireme , a war galley built to accommodate two levels, or banks , of oarsmen. Oarsmen on the lower level rowed oars from ports cut into the side of the vessel, while those above rowed from the deck. This arrangemen...
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Arithmetic
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INTRODUCTION
Arithmetic, branch of mathematics that arises from counting, the most basic mathematical operation.
Subtract the units: 6 - 3 = 3. Then subtract the tens column: 6 – 2 = 4. The results of these two single-digit subtractions, written side by side, provide the answer: Subtraction is a bit more complicated if we need to subtract a larger digit from a smaller one. For example, when subtracting 47 from 92, the units value (7) of 47 isgreater than the units value (2) of 92. We can handle this situation using a procedure called borrowing, which is like carrying in reverse. Ten units can be borrowe...
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Cell (biology) - biology.
proteins, or other proteins required by the cell. While relatively simple in construction, prokaryotic cells display extremely complex activity. They have a greater range of biochemical reactions than those found in theirlarger relatives, the eukaryotic cells. The extraordinary biochemical diversity of prokaryotic cells is manifested in the wide-ranging lifestyles of the archaebacteria andthe bacteria, whose habitats include polar ice, deserts, and hydrothermal vents—deep regions of the ocean un...
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Radio.
signal, such as a musical note. This form of modulation, AM, is used in many radiotelephony services including standard radiobroadcasts. AM is also employed for carriercurrent telephony, in which the modulated carrier is transmitted by wire, and in the transmission of still pictures by wire or radio. See Broadcasting, Radio and Television. In FM the frequency of the carrier wave is varied within a fixed range at a rate corresponding to the frequency of a sound signal. This form of modulation, p...
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Space Exploration - astronomy.
to produce 250,000 newtons (56,000 lb) of thrust. The Germans launched thousands of V-2s carrying explosives against targets in Britain and The Netherlands. Whilethey did not prove to be an effective weapon, V-2s did become the first human-made objects to reach altitudes above 80 km (50 mi)—the height at which outer spaceis considered to begin—before falling back to Earth. The V-2 inaugurated the era of modern rocketry. A2 Early Artificial Satellites During the years following World War II, the...
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Astrobiology - astronomy.
water to help reactions along. American chemists Stanley Miller and Harold Urey tested part of Oparin and Haldane’s hypothesis in the early 1950s by simulating conditions of the early Earth. In whathas become known as the Miller-Urey experiment, the two scientists connected two flasks with a loop of glass tubing that allowed the gases to pass between the flasks.They filled the upper flask with methane, ammonia, and hydrogen—components thought to have been in the early atmosphere. They filled the...
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Water Pollution.
Cryptosporidium in the water supply of Milwaukee, Wisconsin, sickened more than 400,000 people and killed more than 100. H Thermal Pollution Water is often drawn from rivers, lakes, or the ocean for use as a coolant in factories and power plants. The water is usually returned to the source warmer than when itwas taken. Even small temperature changes in a body of water can drive away the fish and other species that were originally present, and attract other species in placeof them. Thermal pol...
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Anatomy.
The body defends itself against foreign proteins and infectious microorganisms by means of a complex dual system that depends on recognizing a portion of the surfacepattern of the invader. The two parts of the system are termed cellular immunity, in which lymphocytes are the effective agent, and humoral immunity, based on theaction of antibody molecules. When particular lymphocytes recognize a foreign molecular pattern (termed an antigen), they release antibodies in great numbers; other lymphocy...
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Algebra
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INTRODUCTION
Algebra, branch of mathematics in which symbols (usually letters) represent unknown numbers in mathematical equations.
B Order of Operations and Grouping Algebra relies on an established sequence for performing arithmetic operations. This ensures that everyone who executes a string of operations arrives at the sameanswer. Multiplication is performed first, then division, followed by addition, then subtraction. For example: 1 + 2 · 3 equals 7 because 2 and 3 are multiplied first and then added to 1. Exponents and roots have even higher priority than multiplication: 3 · 2 2 = 3 · 4 = 12 Grouping symbols override...
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Terrorism.
exploitation, ethnic discrimination, and religious persecution. Perceived inequities in the distribution of wealth and political power have led some terrorists to attempt tooverthrow democratically elected governments. To achieve a fairer society, they would replace these governments with socialist or communist regimes. Left-wingterrorist groups of the 1960s and 1970s with such aims included Germany’s Baader-Meinhof Gang, Italy’s Red Brigades, and the Weather Underground ( see Weathermen) in the...
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Police.
body. In larger agencies, executive officers may be selected through a civil service or merit system, after moving through the ranks from patrol officer to sergeant,lieutenant, captain, and (in still larger agencies) deputy or assistant chief. At the county level, the head of the agency usually holds the title sheriff. The sheriff is almost always elected and has the power to appoint deputies. Sheriffs'departments often provide law enforcement services for unincorporated areas of counties and ar...
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Black Death.
disappeared in the West. V DISAPPEARANCE OF PLAGUE Plague became less common in Europe after the 1530s. The last plague in England was in 1665, the last in Western Europe in 1722. Numerous theories have beenoffered to explain the disappearance of plague. It has been argued that black rats, the primary carriers of plague, may have been replaced by larger brown rats that donot carry the infection. A second theory suggests that increased immunity among the rodents that carried the disease or chang...
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Black Death .
disappeared in the West. V DISAPPEARANCE OF PLAGUE Plague became less common in Europe after the 1530s. The last plague in England was in 1665, the last in Western Europe in 1722. Numerous theories have beenoffered to explain the disappearance of plague. It has been argued that black rats, the primary carriers of plague, may have been replaced by larger brown rats that donot carry the infection. A second theory suggests that increased immunity among the rodents that carried the disease or chang...
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Wilfrid Laurier.
The Manitoba schools were the main issue in the 1896 election. Although the Catholic clergy campaigned against him, Laurier argued in Québec that he would obtainbetter terms for the Catholics by negotiating directly with the provincial government of Manitoba. “Hands off Manitoba” was an effective slogan in the other provinces aswell. A second issue was corruption in the Conservative Party, as a series of scandals had rocked the Bowell administration. Israel Tarte, a former Québec conservativewho...
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Wilfrid Laurier - Canadian History.
The Manitoba schools were the main issue in the 1896 election. Although the Catholic clergy campaigned against him, Laurier argued in Québec that he would obtainbetter terms for the Catholics by negotiating directly with the provincial government of Manitoba. “Hands off Manitoba” was an effective slogan in the other provinces aswell. A second issue was corruption in the Conservative Party, as a series of scandals had rocked the Bowell administration. Israel Tarte, a former Québec conservativewho...
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Tree - biology.
The major parts of a tree are its roots, trunk, leaves, flowers, and seeds. These components play vital roles in a tree’s growth, development, and reproduction. A Roots Trees are held in place by anchoring organs called roots. In addition to anchoring the tree, roots also absorb water and minerals through tiny structures called roothairs. From the roots the water and mineral nutrients are carried upward through the wood cells to the leaves. Although the internal structure of most kinds of roots...
- Styx, River Greek The principle river, or system of rivers, in Hades, the Greek Underworld (1); named for the goddess who carried the same name, Styx.
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From Bulfinch's Mythology: Hercules - anthology.
'…amidst the gardens fairOf Hesperus and his daughters three,That sing about the golden tree.' The poets, led by the analogy of the lovely appearance of the western sky at sunset, viewed the west as a region of brightness and glory. Hence they placed in it theIsles of the Blest, the ruddy Isle Erytheia, on which the bright oxen of Geryon were pastured, and the Isle of the Hesperides. The apples are supposed by some to bethe oranges of Spain, of which the Greeks had heard some obscure account...
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Maya Civilization.
destruction was directed mostly at temples in the ceremonial precincts; it had little or no impact on the economy or population of a city as a whole. Some city-states didoccasionally conquer others, but this was not a common occurrence until very late in the Classic period when lowland civilization had begun to disintegrate. Until thattime, the most common pattern of Maya warfare seems to have consisted of raids employing rapid attacks and retreats by relatively small numbers of warriors, most o...
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Maya Civilization - History.
destruction was directed mostly at temples in the ceremonial precincts; it had little or no impact on the economy or population of a city as a whole. Some city-states didoccasionally conquer others, but this was not a common occurrence until very late in the Classic period when lowland civilization had begun to disintegrate. Until thattime, the most common pattern of Maya warfare seems to have consisted of raids employing rapid attacks and retreats by relatively small numbers of warriors, most o...
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September 11 Attacks - U.
around and flew it back toward Washington, D.C. Flying low and fast, the airplane hit the Pentagon at 9:37 AM. In a bit of good fortune, the plane crashed into the west side of the building, which had recently been reinforced with stronger construction and blast-resistant windows in order to withstand a terrorist attack. Even so, theplane penetrated three of the Pentagon’s five concentric rings, taking a chunk out of the building and incinerating dozens of offices and the people who worked in t...
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John F.
by the United States, was unable to withstand the advance of Communist forces under Mao Zedong (Mao Tse-tung). By the end of 1949 government troops had beenoverwhelmingly defeated, and Chiang led his forces into exile on Taiwan. The triumphant Mao formed the People’s Republic of China. Truman’s critics, includingKennedy, charged that the administration had failed to support Chiang Kai-shek against the Communists. Kennedy easily won reelection to Congress in 1948 and 1950. In 1952 he decided to r...
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John F.
by the United States, was unable to withstand the advance of Communist forces under Mao Zedong (Mao Tse-tung). By the end of 1949 government troops had beenoverwhelmingly defeated, and Chiang led his forces into exile on Taiwan. The triumphant Mao formed the People’s Republic of China. Truman’s critics, includingKennedy, charged that the administration had failed to support Chiang Kai-shek against the Communists. Kennedy easily won reelection to Congress in 1948 and 1950. In 1952 he decided to r...
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Sewage Disposal.
greater load on the piping system and the treatment plant. The amount of storm-water drainage to be carried away depends on the amount of rainfall as well as on the runoff or yield of the watershed ( see Drainage). A typical metropolitan area discharges a volume of wastewater equal to about 60 to 80 percent of its total daily water requirements, the rest being used for washingcars and watering lawns, and for manufacturing processes such as food canning and bottling. B Composition The composi...
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Heredity - biology.
allele from the mother and a mutated allele from the father. In both of these cases, the child will be a carrier. The child develops the disease only if he or she receives amutated allele from each parent. When both parents are carriers, there is a 25 percent chance that a child will be disease-free, a 25 percent chance that it will have thedisease, and a 50 percent chance that it will be a carrier. Examples of genetic diseases that follow the dominant-recessive pattern include sickle-cell anemi...
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Valley.
Except in mountainous terrain, rivers are almost always flanked by floodplains. Floodplains are flat wide deposits of alluvium, river-deposited sediment, on either side of the river channel. During floods, a river overflows its banks and spreads out the sediment near the river to form a floodplain. Floodplains of large rivers, such as thoseof the Mississippi River, can be flat areas tens of kilometers across. River channels migrate back and forth across their floodplains as alluvium is repeate...
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Valley - Geography.
Except in mountainous terrain, rivers are almost always flanked by floodplains. Floodplains are flat wide deposits of alluvium, river-deposited sediment, on either side of the river channel. During floods, a river overflows its banks and spreads out the sediment near the river to form a floodplain. Floodplains of large rivers, such as thoseof the Mississippi River, can be flat areas tens of kilometers across. River channels migrate back and forth across their floodplains as alluvium is repeate...
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Pollination - biology.
rapidly as in cross-pollination, because one plant with a beneficial gene can transmit it only to its own offspring and not to other plants. Self-pollination evolved laterthan cross-pollination, and may have developed as a survival mechanism in harsh environments where pollinators were scarce. IV POLLEN TRANSFER Unlike animals, plants are literally rooted to the spot, and so cannot move to combine sex cells from different plants; for this reason, species have evolved effectivestrategies for ac...
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Mount Everest - geography.
endangered or killed when their tents collapsed or were ripped to shreds by the gales. Hypothermia, the dramatic loss of body heat, is also a major and debilitatingproblem in this region of high winds and low temperatures. Another hazard facing Everest climbers is the famous Khumbu icefall, which is located not far above Base Camp and is caused by the rapid movement of the Khumbuglacier over the steep rock underneath. The movement breaks the ice into sérac (large, pointed masses of ice) cliffs...
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From Bulfinch's Mythology: Proserpine - anthology.
the furrow, the seed failed to come up; there was too much sun, there was too much rain; the birds stole the seeds—thistles and brambles were the only growth.Seeing this, the fountain Arethusa interceded for the land. 'Goddess,' said she, 'blame not the land; it opened unwillingly to yield a passage to your daughter. I can tellyou of her fate, for I have seen her. This is not my native country; I came hither from Elis. I was a woodland nymph, and delighted in the chase. They praised mybeauty, bu...
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Eye.
I
INTRODUCTION
Eye, light-sensitive organ of vision in animals. The eyes of
Several structures, not parts of the eyeball, contribute to the protection of the eye. The most important of these are the eyelids, two folds of skin and tissue, upper andlower, that can be closed by means of muscles to form a protective covering over the eyeball against excessive light and mechanical injury. The eyelashes, a fringe ofshort hairs growing on the edge of either eyelid, act as a screen to keep dust particles and insects out of the eyes when the eyelids are partly closed. Inside the...
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Library of Congress.
manuscripts, books, and films. The Digital Library’s eventual goal is to make available 80 million items from the Library of Congress’s collection that are not easilyavailable elsewhere. V ORGANIZATION AND FUNDING The librarian of Congress serves as the director of the institution. Tradition, politics, and strong personalities have shaped the function of this office. Although the Libraryof Congress was established in 1800, the office of librarian was not created until passage of a law in 1802....
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Babylonia - USA History.
Pharmacology, too, doubtless had made considerable progress, although the only major direct evidence of this comes from a Sumerian tablet written several centuriesbefore Hammurabi. C Legal System and Writing Law and justice were key concepts in the Babylonian way of life. Justice was administered by the courts, each of which consisted of from one to four judges. Often theelders of a town constituted a tribunal. The judges could not reverse their decisions for any reason, but appeals from their...
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Aztec Empire.
tribute to the empire in agricultural products, which were used to finance public projects. All able-bodied men owed military service to the empire. Citizens could also bedrafted to work on public lands or build temples, dikes, aqueducts, and roads. Although Aztec society had strict classes, a person’s status could change based on his or her contribution to society. Commoners could improve their rank, especially byperforming well in battle, and become prosperous landowners. Young people of some...
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Aztec Empire - USA History.
tribute to the empire in agricultural products, which were used to finance public projects. All able-bodied men owed military service to the empire. Citizens could also bedrafted to work on public lands or build temples, dikes, aqueducts, and roads. Although Aztec society had strict classes, a person’s status could change based on his or her contribution to society. Commoners could improve their rank, especially byperforming well in battle, and become prosperous landowners. Young people of some...
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Inca Empire.
The Incas’ public works were built through a labor tax known as mit’a. This tax required most people incorporated into the Inca Empire to provide labor for public worksduring certain portions of each year. This labor tax supported large-scale public works that required the marshalling of large labor forces, such as for the building offorts, roads, and bridges, or the mining of metals and gems. It also allowed the emperor to raise large armies to undertake wars of conquest. Road building was impo...
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Inca Empire - History.
The Incas’ public works were built through a labor tax known as mit’a. This tax required most people incorporated into the Inca Empire to provide labor for public worksduring certain portions of each year. This labor tax supported large-scale public works that required the marshalling of large labor forces, such as for the building offorts, roads, and bridges, or the mining of metals and gems. It also allowed the emperor to raise large armies to undertake wars of conquest. Road building was impo...
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Native American Policy.
of white settlement dominated policy during the second quarter of the 19th century. IV REMOVAL PERIOD The idea of moving Native Americans to a different part of the country was not new. After the Louisiana Purchase in 1803, President Thomas Jefferson had suggestedthat tracts of land in this vast new territory could be given to native peoples if they agreed to cede their lands in the eastern part of the country. Transfers occurred in apiecemeal way, but no consistent removal program developed u...
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Olympic Games.
the next decade nearly all the ISFs abolished the distinction between amateurs and professionals, accepting so-called open Games. One of the most visible examples of the policy change came in 1992, when professional players from the National Basketball Association (NBA) were permitted to play inthe Summer Games in Barcelona, Spain. Professionals from the National Hockey League (NHL) became eligible to participate beginning with the 1998 Winter Olympics inNagano, Japan. V CEREMONIES The Olymp...
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Heart.
situation. A Cardiac Cycle Although the right and left halves of the heart are separate, they both contract in unison, producing a single heartbeat. The sequence of events from the beginning ofone heartbeat to the beginning of the next is called the cardiac cycle. The cardiac cycle has two phases: diastole, when the heart’s chambers are relaxed, and systole,when the chambers contract to move blood. During the systolic phase, the atria contract first, followed by contraction of the ventricles. T...
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Ulysses S.
In the autumn of 1862, Grant began planning the drive on Vicksburg, Mississippi, the Confederate stronghold on the Mississippi River, which was to yield one of hisgreatest military successes. After several unsuccessful attempts on Vicksburg during the winter, Grant devised a new strategy of attack. In April 1863 he marched hisarmy south along the west side of the river to a point well below the heavily defended city. There, with the aid of the Union river fleet, he crossed the river and began as...
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Ulysses S.
In the autumn of 1862, Grant began planning the drive on Vicksburg, Mississippi, the Confederate stronghold on the Mississippi River, which was to yield one of hisgreatest military successes. After several unsuccessful attempts on Vicksburg during the winter, Grant devised a new strategy of attack. In April 1863 he marched hisarmy south along the west side of the river to a point well below the heavily defended city. There, with the aid of the Union river fleet, he crossed the river and began as...
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American Westward Movement - U.
British expansion. However, Native Americans of the Great Lakes and Ohio Valley lashed out against the English in an attempt to preserve their independence, theirland, and their way of life. With the Ottawa chief Pontiac as their most visible leader, the tribes waged a bloody and costly war. As a result, the British governmentdecided to keep the white settlers apart from the Native Americans. It issued the Royal Proclamation of 1763, banning all white settlement beyond the Appalachians andstatin...
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Evolution - biology.
genetic diversity to extinction. Sexual reproduction ensures that the genes in a population are rearranged in each generation, a process termed recombination. Although the combinations of genes inindividuals change with each new generation, the gene frequency, or ratio of different alleles in the entire population, remains relatively constant if no evolutionaryforces act on the population. One such force is the introduction of new genes into the genetic material of the population, or gene pool...
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Archaeology.
Prehistoric archaeology is practiced by archaeologists known as prehistorians and deals with ancient cultures that did not have writing of any kind. Prehistory, a term coined by 19th-century French scholars, covers past human life from its origins up to the advent of written records. History—that is, the human past documented insome form of writing—began 5000 years ago in parts of southwestern Asia and as recently as the late 19th century AD in central Africa and parts of the Americas. Becaus...
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American Civil War.
free state to keep the balance in the Senate. It also provided that slavery would be excluded from the still unorganized part of the Louisiana Territory. A line was drawnfrom Missouri’s southern boundary, at the latitude of 36°30’, and slavery would not be allowed in the territory north of that line,with the exception of Missouri. B Compromise of 1850 Agitation against slavery continued in the North. The South reacted by defending it ever more strongly. The Mexican War, by which the United Stat...
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American Civil War - U.
free state to keep the balance in the Senate. It also provided that slavery would be excluded from the still unorganized part of the Louisiana Territory. A line was drawnfrom Missouri’s southern boundary, at the latitude of 36°30’, and slavery would not be allowed in the territory north of that line,with the exception of Missouri. B Compromise of 1850 Agitation against slavery continued in the North. The South reacted by defending it ever more strongly. The Mexican War, by which the United Stat...
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Ancient Rome .
attributed to Numa, including the selection of virgins to be priestesses of the goddess Vesta. He also established a calendar to differentiate between normal workingdays and those festival days sacred to the gods on which no state business was allowed. His peaceful reign lasted from 715 to 673 BC. Under Tullus Hostilius (672–641 BC) the Romans waged an aggressive foreign policy and began to expand their lands by the conquest of nearby cities like Alba Longa. When the warlike King Hostilius co...
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Ancient Rome - USA History.
attributed to Numa, including the selection of virgins to be priestesses of the goddess Vesta. He also established a calendar to differentiate between normal workingdays and those festival days sacred to the gods on which no state business was allowed. His peaceful reign lasted from 715 to 673 BC. Under Tullus Hostilius (672–641 BC) the Romans waged an aggressive foreign policy and began to expand their lands by the conquest of nearby cities like Alba Longa. When the warlike King Hostilius co...