Calendar: Humanity's epic struggle to determine a true and accurate year
by David Ewing Duncan
(Avon, 1998)
According to Church rules, Easter is celebrated on the first Sunday after the first full moon after the spring equinox.
Pages 3-4.
Europeans after the collapse of Rome either ignored or did not understand complex fractions. They tended to round off anything but a simple fractions such as one quarter or one half.
Page 5.
Egypt was the first ancient civilization to correct the error of the moon and embrace the sun.
Page 15.
The three seasons of life in Egypt: flooding, growth, and harvest. The regularity of this cycle and the availability of the great river as a natural timepiece provided an easy and dramatic alternative to the moon.
Page 16.
The Maya also invented a calendric system so accurate that when the Spaniards conquered them in the early sixteenth century, the Julian calendar that conquistadors brought with them was less precise.
Page 18.
Mesoamericans counted with their fingers and their toes.
Page 19.
By legend, the Roman calendar - our calendar - was created by the mythic first king of Rome, Romulus, when he founded the city in 735 B.C. - year 1 in the Roman calendar, knows as ab urbe condita (A.U.C.), “from the found ng o f the city.” Page 30. Caesar’s calendar also injected a new spirit into how people thought about time. Before, it ad been thought of as a cycle of recurring natural events, or as an instrument of power But no more. Now the calendar was available to everyone as a practical, objective tool to organize shipping schedules, grow crops, worship gods, plan marriages, and send letters to friends.
Page 37.
… the new Julian calendar introduced the concept of human beings ordering their own individual lives along a linear progression operating independent of the moon, the seasons, and the gods.
Page 37.
For the first time in European history the coming Pax Romana would foster a middle class of raders, bureaucrats, soldiers, lawyers, moneylenders, and craftsen who came in contact with the notion of measuring time using numbers and calculations
Page 37.
The Roman Empire in 312 would have been unrecognizable to Julius Caesar. Rome itself and its ancient institutions of temple and Senate had been largely eclipsed by the all-powerful imperium, a massive bureaucracy of civil servants provincial governors, and army officers headed up by a single man - the emperor.
Page 41.
By the 300s, however, this old order was all but shattered, with emperors ruling at the whim of the legions, and the empire weakened by a general stagnation as it ceased to expand military and economically and became mired in bankrupting wars inside and out.
Page 41.
Only over the course of several years did Christianity gradually win out, perhaps because the Christians offered a more effective power base, or because Constantine found the tenets nd organizational structure of the Christian Church easier to co-opt and merge into the existing imperial structure.
Page 43.
Inevitably Constantine’s new order, like Caesar’s three and a half centuries earlier, got around to putting its stamp on the calendar, in this case by creating a new, religiously inspired system of measuring time. He did this by leaving intact Caesar’s basic calendar of 365¼ quarter days and 12 months, while making three major changes within this structure: the introduction of Sunday as a holy day in a new seven-day week; the official recognition of Christian holidays such as Christmas with fixed dates; and the grafting onto the calendar of the Easter celebration, which is not a fixed date, being tied to the Jewish lunar calendar in use when Christ was crucified. The existence of these two types of holidays, fixed and floating, is where Christians get the terms “immovable feast” and “movable feast.”
Pages 43-44.
Even after Constantine’s edict about Sunday, it took another generation or two for the seen-day week to catch on throughout the empire. The 24-hour system took longer, having to wait until the invention of the mechanical clock in the Middle Ages by monks anxious to observe with precision their canonical hours. Before this, people marked the passage of time during the night by using the stars and during the day either by eyeballing the sun or by listening to public announcements of the time
Pages 47-48.
Saxons also gave us the word day, which comes not from the Latin dies but the word in Saxon for “to burn,” during the hot days of summer.
Page 48.
For Constantine the issue was not so much how to determine the date for Easter, but how to get the various factions of Christianity to agree to celebrate the Resurrection on the same day, even if technically this date was not exact. Politically this was crucial to establishing one state religion, with one set of rules.
Page 48.
Constantine was so anxious to convene this meeting that he paid the bishops’ expenses, placing at their disposal the empire’s system of public conveyances and posts along its highways.
Page 49.
Christianity had operated less as a single cohesive religion than as a collection of sects and denominations following the same basic tenets but differing on points major and minor - such as when to celebrate Easter. Unity had always been a goal, though most congregations had remained more or less independent of one another, with doctrine and details of worship left to the local elders and members to decide.
Page 50.
Constantine’s mandate at Nicaea was to put a kid on this free-for-all by establishing a set of uniform rules governed by a centralized structure headed by himself as emperor.
Page 50.
The problem arose because no one who witnessed Christ’s death and resurrection had thought to jot down a date.
Page 51.
The vagueness rose because the earliest Christians cared little or nothing about dates, for the understandable reason that Jesus’s disciples and first followers fervently believed in their savior’s imminent return. For them time was irrelevant, a point underscored by the apostle Paul, who did not date his letters that appear in the New Testament.
Page 51.
When Jesus failed to return immediately, Christians realized they needed some sort of system for dating. By the second century they started writing schedules of when to worship, and crude calendars of saint’s days and other Christian holidays. They also began to argue about dates, such as whether to worship on Saturday or Sunday, and how to draw up a chronology of events in Jesus’s life.
Page 51.
By the third century a rising anti-Semitism among non-Jewish adherents added to the confusion, as Christians became biased against using dates that depended on when Jewish priest determined the start of Nisan to be.
Page 52.
Far more important than the nature of Christ or the date of Easter was Nicaea’s codification of Constantine’s fusion of church and state, an expedient political move by this shrewd emperor that was to link inexorably the Church to secular power, wealth and absolutism for many centuries to come - first as an adjunct to imperial Rome and later as an independent entity that derived its all-embracing influence from its own imperial-style hierarchy and assumption of power over Christian domains.
Page 54.
Chaos was not the only outcome of the empire’s collapse, Nor did every Roman institution falter. One, in fact, grew stronger amidst the disorder and decay: the Catholic Church. Originally designed by Constantine as a vehicle to enhance the political might of Rome, the church ended up superseding it, retaining its power and influence in the ecclesiastic realm, particularly as the barbari dropped their pagan gods and embraced a Church that demanded - and got - an allegiance much stronger than the imperium itself had ever known.
Page 56.
As Rome's political power ebbed and the Church rose from its ashes, the sacred soon overwhelmed the profane.
Page 57.
The backdrop of the empire’s sloe collapse obviously influenced Augustine’s philosophical outlook, which favored a secure perfect “city of God” over the faltering “city of man.”
Page 57.
Known as the last great intellectual of the classical era, Augustine set out to create a philosophical structure that linked his new religion to one of the giants of the ancient world, Plato, equating this long-dead Athenian’s ideas about a prime mover/creator with the Christian God, and Plato’s notion of a perfect universe, existing beyond our flawed world, with the Christian concept of heaven.
Page 57.
Dissension over details in the Easter calculation was one reason why Augustine at times became impatient with mathematicians.
Page 61.
They could think of only one thing to do: withdraw from the broken walls and ravaged streets of Rome and other cities to their estates in the country, which over the years of turmoil Rome’s powerful families had fortified with stout walls and defenses in what became early prototypes for medieval castles.
Page 67.
Cassiodorus embraced both ancient and Christian thought, insisting that the monastery should be a place to worship and to preserve a spirit of learning.
Page 68.
In about 540, the year Ravenna fell to Justinian and Cassiodorus moved to Constantinople, Benedict wrote a guide to what he considered roper worship, known as The Benedictine Rule.
Page 70.
Wanting to be sure that a monk in Naples was saying the same Psalm at the same hour as one in Provence, he ordered that time be kept accurately and objectively by using the best clocks then available the sundial and water clock, and later a“candle clock”
made to burn in measured hourly increments.
Page 70.
As something that set apart monks from the rest of society, the Benedictine system also engendered in laymen a sense that following a strict schedule of duties according to the clock was an important part of religious devotion. Eventually, the Benedictine’s sense of time crept into everyday life and language. The word siesta, for instance, comes from the abbot setting aside an hour of rest after the midday meal at the sixth hour.
Page 71.
Some historian believe that modern capitalism, with its use of time as an economic unit - for wages, contracts, and interest rates - grew in part out of the Benedictine fixation on measuring time.
Page 71.
Dionysius’s contribution to our calendar went far beyond the pedestrian task of calculating another 95 years of Easters. When he published his tables he included a reform that was little noticed in his own day but now affects virtually everyone in the world: the system of dating known as anno Domini (A.D.), “the year of our Lord” - which many people now call the common era (C.E.)
Page 74.
Dionysius did not designate a year 0 because the concept of zero had not yet been invented.
Page 74.
Unfortunately, Dionysius almost certainly got his dates wrong. The true moment of Christ’s birth is unknown and a matter of immense controversy even today, given the vague and contradictory information available on Christ’s early life. The Gospel of Matthew claims he was born in the time of Herod the Great, who died in 4 B.C. This means the birth must have occurred before this date. Other Gospels and historical sources suggest dates ranging from 6 or 7 B.C. to A.D. 7, though most historians lean toward 4 or 5 B.C.
Page 75.
… Christians did not use the inverse of anno Domini, B.C. (for “Before Christ”) until 1627, when the French astronomer Denis Petau apparently became the first ever to add B.C. to dates while teaching at the Collège do Clermont in
Paris.
Page 75.
Bede was almost sixty years old in 731 when he published his account of the prophecy and slaughter in his Ecclesiastical History of the English People. A monk, teacher, and choirmaster at the Saxon-era monasteries of Wearemouth and Jarrow in Northumbria, he lied far away from the centers of culture and learning (such as they were) in his age - which makes his accomplishments all the more astonishing. For without ever leaving the neighborhood of his twin monasteries, Bede wrote some sixty books on subjects ranging from commentaries on the Bible to works on geography, history, mathematics, and the calendar
Page 78.
Bede and his countrymen were only vaguely aware of events beyond the frigid, turbulent waters of the Mare Germanicum, now known as the North Sea.
Page 80.
Scholarship in many places was reduced to learning a few key subjects by rote and devoting one’s life to copying ancient manuscripts, which most monks held in awe as artifacts of a glorious past, but few understood. A number of monks lost their eyesight scratching out copies in the semidarkness of their stone cells, since candles were not allowed for fear fire would consume the ancient parchments.
Page 81.
The only other truly notable time reckoner in thee dark days of the early Middle Ages was Isidore of Seville (560-636), a Roman ecclesiastic and scholar living in another distant outpost of the former empire: Visigoth Spain.
Page 81.
Like Islam, it had fused its doctrines and faith with the apparatus of political power - first under the aegis of Rome and more recently under the sponsorship of barbarian kings converted to Christianity. This made the spread of Christianity less an individual decision than a strategic ideology of kings, nobles, and through them entire peoples.
Page 83.
By the time Bede was a young man, the Church’s conversion of barbari and the conquests of Islam had precipitated a titanic shift in Christianity’s geography, transforming it form a religion primarily of the Mediterranean and Near East to a European religion.
Page 83.
His History is important beyond the stories it tells because Bede chose to use Dionysius Exiguus’s scheme of anni Domini to date the events in his chronology - the first itme this was done in such a prominent and widely read history.
Page 84.
Before Bede historians had dated events using the reigns of kings and emperors.
Page 84.
With the conversion of the Saxons cam the reintroduction of Caesar’s calendar in Britain, with certain Anglo-Saxon modifications. For instance, the substitution of Germanic planet-gods for those of Rome to designate the days of the week, and the use of the goddess Eostre to name Easter - which then and now is officially called the Feat of the Passion by Catholics.
Page 86.
When Augustine arrived in Britain in 597 he was, at best, only vaguely aware that Christians already lived on the island - the Celts.
Page 86.
Following the ancients, he writes that this universe consists of the elements earth, air, fire, and water, and that the earth lies at the center - surrounded, as Christian theology taught at that period by seen heavens: air, ether; Olympus, fiery space, firmament, the heaven of angels, and the heaven of God.
Page 89.
He also explains the divisions of time as they then existed, following Isidore of Seville’s list, from the smallest unit to the largest: moments, hours, days, months, years, centuries, and ages.
Bede also writes about the long-held Christian belief that the earth had passed through six ages since the Creation. The first five, he said, had been marked by the Creation, the Flood, Abraham, David, and the captivity of the Jews in Babylon. The sixth and current age began with the birth of Christ. … Western chronographers before and after Bede used this passage to date the beginning of the world to about five thousand years before Christ’s birth.
Pages 89-90.
When confronted with the need for complex fractions in calculating time, he simply rounded up or down.
Page 92.
Even more remarkable was Bede’s appreciation of time as being real and measurable; something that could be organized into an ordered system of epochs, years, months, and days. For Bede time moved in a progression along a calendar, a concept few people in his day embraced.
Page 93.
Charlemagne attempted to reform his calendar, too. Most important, he and his scribes incorporated into the civil machinery of his empire the anno Domini system of dating favored by Dionysius and Bede. Charlemagne also followed in many of his decrees a growing trend in Europe to number the days of the months in sequential order instead of using the cumbersome Roman system of calends, nones, and ides.
Page 96.
Alcuin served as Charlemagne’s personal tutor between 781 and 796, as this largely untaught barbarian chieftain made an admirable attempt to educate himself in between battles and campaigns.
Page 97.
Medievalists today insist Charlemagne’s intellectual accomplishments were mostly superficial, the pastime of a bright but unrefined warlord who treated learning as a precocious child might admire a shiny stone or delight in trying to work out a riddle or a puzzle.
Pages 97-98.
As a barbar fascinated by these symbols of a sophisticated culture, he did not entirely comprehend them but hoped to emulate them nonetheless. Even worse, most of these scholars were barely educated themselves.
Page 98.
Charlemagne himself, educated as a warrior in the centuries-old gradation of Germanic leaders and kings, could barely read and could not write despite years of lessons from Alcuin and Peter of Pisa - and despite the insistence of Einhard that the emperor had mastered astronomy and time reckoning.
Page 98.
Most of his nobles were entirely illiterate. Nor could most of his scribes and scholars except Alcuin write in decent Latin.
Page 98.
In 800 Charlemagne accepted the title of Holy Roman Empeor from the pope, an event that signaled the Church’s acknowledgment of what had been the political reality in Europe since at least the beginning of the Moslem conquests: that St. Peter’s could no longer depend on either local Germanic kings in Italy or the Byzantines to protect Christendom in the West.
Page 99.
It also acknowledged and reinforced two enormous changes in Europe that would profoundly affect all aspects of life over the next several centuries, including the calendar and the science of time reckoning.
First was the consolidation and victory of the Catholics in finally eradicating virtually all other sects in the West, as all Christians fell in line behind their rules for everything from dating Easter and punishing heresy to when it was acceptable to have sex. The second was formalizing the rising new political and economic order in Europe we call feudalism.
Page 100.
The princes of Europe and the pope essentially agreed to a pact that gave the Catholic Church authority over all religious matters - including most science - backed by the power of the princes and their gendarmes and armies.
Page 100.
In 800, cathedrals, castles, and local administrative manors for kings and nobles were the most highly organized communities in western Europe.
Page 101.
In Charlemagne’s time and throughout the Middle Ages, over half the children died before age five. Life expectancy was only 35 years.
Page 101.
Even in good times the diet was poor: barley or millet with a few vegetables in gruel served daily with a piece of stale bread and an occasional slice of cheese of fruit.
Page 102.
Poems and stories form that long-ago era tell of a great fear of wild animals; dark, haunting forests where no one dared venture; and imaginary beasts and devils with fiery eyes and horns. People were earthy and pragmatic, but in the absence of scientific explanations for why the sun rose and fell and countless other mysteries they were also highly credulous and susceptible to even the most ludicrous superstitions and rumors.
Page 102.
Europeans in the age of Charlemagne were primarily interested in predictable cycles and cues from nature.
Page 102.
Typically a saint’s day fell on the d ate of his or her martyrdom. Complete lists of saints began appearing in the fourth century, describing n often gory detail their burnings, hackings, crucifixions, mutilations, and drownings.
Page 104.
Writing and copying calendars of saints' lives became a major focus of scholars and artists during the Middle Ages. Every morning monks read descriptions of that day's saints.
Page 105.
Time in Christianity was, of course, heading someplace: to Christ's second coming and eventually to eternity, events that would occur along the same timeline as past events.
Page 107.
Most people who thought about such things believed that however old the earth might be, the end was near.
Page 108.
Even though Charlemagne saw clocks as curiosities, his keen interest in them and the idea of telling time made a lasting impression on future generations. At the same time a new invention was reading slowly across the West: the bell. Called glocka in German - whence came our word clock - bells were used to signal hours and other times of the day.
Pages 108-109.
Bells probably spread first to monasteries, where monks used hand bells.
Bels probably had a minimal impact on the average person. Yet they were the first mechanical “clocks”to govern everyday life in Europe, usually rung according to time as measured on a water clock or sundial.
Page 109.
… one of the great mathematical discoveries in history: the system of arranging numbers that mathematicians call “positional notation,” now used by virtually the entire world. …
In positional notation, numbers are arranged in a sequence whereby each number stand s for itself multiplied by a base number that increases by one power of the base with each place.
Page 116.
Our number zero comes from sifr, the Arabic version of sunya, which medieval Europeans altered to ziphirum in Latin. Greeks of the classic age had no symbol for zero, because their numerical system did not require a zero place.
Page 121.
Fractions posed a huge problem for humanity through most of history.
Page 123.
This powerfully reinforced the belief in the Middle Ages that if such a number existed, it was known only to God, when in truth the number was simply beyond the capability of the symbols and numerical system in use at the time - and continued to be until the thirteenth and fourteenth centuries, when Europeans began broadly adopting the earliest versions of the modern decimal system.
The idea of using decimal fractions came to Europe form the Arabs.
Page 124.
… the Arabs did not follow the example of the barbariin the West, who had looted and destroyed the cities and province of Rome. Instead the Arabs assimilated the cultures of the peoples they conquered - much the same way the early, uncouth Romans had done centuries before when they eagerly embraced and absorbed the cultures they conquered in Greece and the Near East.
Page 129.
Fearing for their lives as well as their intellectual freedom, many of these scholars had fled to Persia where they established a kind of Academy in xile.
Page 130
Having come from a desert where few were literate and the lifestyle modest, they brought little material culture to the ancient civilization snow under their sway. Their significant contributions were language and religion, and this is where their talent as master assimilators came into the fore, as they seized on the clothing, dress, architecture, philosophy, literature - and science - of the Persians, Greeks, and Indians they now ruled.
Page 131.
The Islamic calendar … - whose year 1 began in our year A.D. 622, when Mohammed fled Mecca for Median - was established by the second caliph, Umar, around A.D. 634. Years in the Islamic calendar are indiated with the abbreviation A.H., which stand for the Latin anno hegirae, or ‘The Year of the Migration.” Since then it has been running at the standard lunar time of 354 days a year.
Page 134.
Men who would be raised and educated not in monasteries but in Europe’s slowly reviving cities, where news of other cultures was arriving along with the first scatterings of long-lost texts by Greeks and newer writings by Arab and Indian scholars.
Page 142.
For the average Christian in 1100 Catholicism was mostly a huge comfort: a universal set of laws and beliefs that provided a powerful sense of spiritual unity and a deeply desired salvation, particularly for serfs and peasants - which meant just about everyone.
Page 144.
The pace was most brisk in Italy, where merchandise arrived form Europe’s interior to be loaded on ships in Venice, Naples, Pisa, and Rome and shipped to Byzantium and Syria. These vessels then returned to Italy with holds stuffed with wares to be offloaded and carried in caravans to Paris, Cologne, distant London, and hundreds of expanding market towns in between.
Page 145.
No consensus existed on matters as basic as when the year started, which could vary from town to town and fief to fief. Some localities celebrated New Year's Day on Christmas … Other communities had the year starting on Good Friday, or the day after, or on Easter. Still others began their year in March, around the time of the vernal equinox, when some old German calendars and Rome’s pre-Julian calendar began.
Pages 145-146.
As trade grew more lively, however, people tried to sort out the Babel of day names and dates - with little success. This is because no central authority existed to standardize the calendar other than the Church. St. Peter’s though, remained fairly locked into the notion that tine belonged to God, not to bankers and sea captains: a core belief that would have to be changed before the calendar could be reformed.
Page 146.
Most Europeans were ignorant even of the Byzantines, beyond a few key ports and cities in Italy that had kept in furtive contact over the centuries.
In part this was understandable. Most outsiders were enemies, including at times the Byzantines, who continued to challenge the Lombards and other Westerners for control of southern Italy, and were sometimes rivals in the east during various crusades. As for the Arabs, they stood like a colossus astride the borders of Europe, a military superpower that fearful Christians thought of not as an enlightened culture of scholars but as the army of Satan himself. How else to explain their triumphs against God’s people?
Page 148.
For three centuries, from the mid-700s to the mid-1000s, Arab armies and raiding parties menaced the western Mediterranean, dominating its sea lanes and leaving Europeans terrified they would launch a major invasion.
Page 148.
The invention of the decimal point is usually attributed to either mapmaker and Galileo rival G. A. Magini (1555-1617) in a 1592 work, or to the leading astronomer on Gregory XIII’s calendar commission, Christopher Clavius (1537-1612), who used them in a table of sines in 1593.
As for zero, its first significant appearance in Europe comes during the eleventh and twelfth centuries, at roughly the same time as the other nine Hindu-Arabic numbers started to come into wide use - first as a place marker on counting boards devised by Gerbert and others, then as a digit in positional notation.
Page 152.
This would become the central dilemma of scholars from 1100 to 1300: how to account for knowledge that seemed to come out of nowhere, and in essence offered a new kind of religion that put its faith in observation and logic.
Page 153.
… the first large clock appearing in English at Windsor Palace in 1351.
Page 155.
The young Abelard epitomized the sort of person drawn to the new style of learning in the twelfth century. Brilliant and relentless in his scholarship freewheeling and passionate in his lifestyle and personality, he represented a profound shift away from the cloistered approach of learning and toward a search for the truth in open discourse and disputation, and through the unfettered power of his intellect.
Page 157.
Many of the earliest university teaches came form the ranks of translators who had trekked to Toledo and Sicily and returned to teach the “secrets” of Aristotle, al-Biruni, and Euclid.
Page 157.
The university curriculum began with training in four or five general areas: theology, law, medicine, arts or philosophy, and music. The masters also taught what was known about astronomy, mathematics, and other sciences, though these more empirical subjects tended to be overshadowed by the deep philosophical and theological controversy touched upon by Hermann the Lame, promulgated by the Arabs, and shouted about by Abelard: what to do about the growing evidence that two truths existed, that of the Church and that suggested by nature and reason.
Pages 157-158.
Abelard himself was eventually destroyed , in part because of his own outrageous departure from acceptable behavior when he wooed the young Héloïse, the teenage niece of a prominent canon in Paris, had a son with her, then married her in secret - which prompted the girl’s irate uncle to have the master scholar castrated.
Page 158.
Aquinas made the breathtakingly bold assertion that Platonic universals could be proven by Aristotelian logic. In other words, this brilliant Italian philosopher and theologian, born in a castle to the noble counts of Aquino and trained in Naples and Cologne, attempted in a comprehensive manner to unite the worlds of Aristotle and Plato.
Page 160.
Thomas was made a saint in 1323.
Page 161.
Bacon argued that nature had been established by God and therefore need to be explored, tested, and absorbed to bring people closer to God. He warns that a failure to embrace science is an affront to God and an embarrassment to Christians, who were forced to acknowledge the superiority of Arab science.
Page 165.
Bacon's ardor for correcting obvious errors came in part from a belief that the Antichrist was about to arrive on earth.
Page 166.
Bacon argued … that natural time was God’s time, and that time as interpreted by an authority such as the Church can be mistaken.
Page 166.
Originating in China or India - no one knows for sure where - the bacterium Yersinia pestis was passed to humans by fleas carried by rats.
Page 171.
The plague could strike someone down in three days or less. Eve-witnesses tell of people going to bed healthy only to die before they awoke. Doctors sometimes caught the malady at a bedside and succumbed before their patient.
Page 171.
Probably some 30 million perished in about two years - a third of all Europeans.
Page 172.
The resulting collapse of confidence in all authority eventually led to peasant revolts and riots across Europe as kings and the clergy tried, and failed, to revive the old feudal order, which was becoming moribund anyway with the rise of trade and commerce in the cities.
Page 172.
It was the crossed-star theory that became the accepted explanation for the Black Death among
intellectuals.
Page 173.
Starting in the early 1300s, with the first mechanical clocks, came the conception of the hour as a secular unit of time.
Page 173.
By the mid-1400s Europe was beginning to recover from the disastrous effects of the plague. … Byzantium fell in 1453, when te Turks breached the once invincible walls of Constantine’s ancient city using a newly arrived invention, the cannon.
Page 177.
They learned to use cannon and gunpowder, borrowed from the Turks and Arabs, who had borrowed them from the Chinese.
Page 178.
Among other things, the printing press allowed calendars to be mass-produced, bringing for the first time a standardized, easy-to-read rendering of days, weeks, months, and holidays to people other than astronomers, ecclesiastics, kings, and tax collectors.
Page 178.
… though he followed his act of defiance by preaching what amounted to a direct challenge against Rome. Insisting that the Bible should be the sole authority in the Church and that salvation lay solely in faith - the first denying the pope’s authority and the second contradicting core Catholic doctrine - Luther touched a powerful nerve of discontent.
Pages 181-182.
First is the seasonal or tropical year, which is the time it takes for the seasons to cycle through and start again. This has been the ’year” we have referred to throughout this book and which is the basis for our season-based calendar year. It is determined by measuring the length of time between vernal equinoxes, when the planes of the equator and the sun’s ecliptic interest in the spring. The other year is the “star” year, also called the sidereal year, which measures the time it takes for the earth to revolve around the sun back to an exact starting point in space. The difference in these two “years,” we now know, is about twenty minutes, with the tropical year running faster each year than the sidereal year. Known as the precession of the equinoxes, the phenomenon of a slower tropical year was first discovered by Hipparchus in ancient Alexandria.
Pages 182-183.
Despite Copernicus’s fears, his book initially attracted little controversy. Very few people could understand it, and those who did went along with a preface added to the book without Copernicus’s permission that described its contents as mere conjecture rather than probable fact.
Page 184.
For seventy years the Roman Church remained silent about Copernicus.
Page 185.
In the years immediately following the publication of De revolutionibus astronomers reading it ere less interested in the sun-versus-earth debate than in studying and using Copernicus’s observations and general theories on planetary motions - including his estimates of the length of the year and his measurements of lunar phases.
Page 186.
Gregory also suppressed knowledge that failed to agree with Church dogma, establishing an infamous index of banned books that later listed Copernicus’s De revolutionibus.
Page 191.
The Church remained the only force in Western Europe capable of exerting anything like a universal authority.
Page 192.
Rome itself in the 1570s looked ruined and exhausted, its ancient monuments, palaces, and temples shattered and half buried by dirt and rubbish, its ancient walls and columns picked apart for centuries and incorporated into a disconcerting hodgepodge of old and new Even the once mighty Forum, where 16 centuries earlier Cesar had stood up to announce that he was establishing a new calendar, was now called the Camp Vaccino, the “Cow Pasture.” Buried under eons of trash and dust, and mostly dismantled for its marble and bricks, this place that had been the center of the Roman world was not he domain of bovines chewing tufts of grass growing a round broken columns and archways.
Page 193.
Diminished now from as many as a million people in imperial times to perhaps sixty thousand - though in the 1570s it was beginning to grow again - the city’s inhabited areas were clustered near the Tiber, where those who stayed through the barbarian invasions had moved for easy access to water after the aqueducts were cut.
Page 193.
The other great chronologist of the early modern era was Sir Isaac Newton (1642-1727), whose work in astronomy finally demolished what was left of the Ptolemaic school in planetary theory, and whose work on light, gravity, and mathematics launched modern physics. … He insisted … that the world was created by God in 4004 B.C., as determined by Irish archbishop and student of the Scriptures James Ussher (1581-1656).
Page 207.
On February 24, 1582, the 80-year-old Pope Gregory XIII sat down at a table that is still preserved at Mondragone and signed the bull that would make this the last year of Julius Caesar’s calendar, at least for those staunchly Catholic countries still willing to accept a decree from the
much-deflated authority of the Roman See.
Page 208.
Gregory’s bull was a regrettably political document, a command from the pope as strident as anything produced by the pontific pen during these tumultuous days of the Counter-Reformation.
Page 211.
… people now had to cope with two calendars: the Julian in the Protestant countries and the Gregorian in the Catholic ones - soon to be known as the “old style” and the “new style,” or P.S. and N.S.
Page 214.
In 1582 most people still led very insular lives compared to today, seldom straying from their villages and fields.
Page 216.
Most clocks kept time only to the quarter hour.
Page 217.
… few people probably focussed on the role of science, not realizing that this shift was one
of the first instances in the early modern age where a change affecting almost everyone was compelled less by religion than by a new respect for scientific accuracy - in this case, for getting the time right.
Pages 217-218.
After the attempted invasion by Spain in 1588 - launched with the support of the pope - the revulsion for all things Roman made any reform impossible.
Page 222.
It would be another 170 years before Britain finally adopted the Gregorian calendar; it was one of the last major European countries to do so. This was despite serious reform attempts in 1645 and 1699, both blocked by a still strident Church of England and by Puritans taking the line that the “old stile” calendar was the true style of God.
Page 222.
… with overseas letters dated with two dates - O.S. and N.S. Over the years the English even seem to have developed a certain amount of pride (or arrogance) in being different - something akin to Americans’ turning up their noses at the metric system today.
Pages 222-223.
Britain was not the last country to change in Europe. Sweden changed the nest year, in 1753. Then there is a long gap, with the heavily Greek Orthodox countries in the Balkans waiting until the early twentieth century. Bulgaria made the switch in either 1912, 1915, or March 1916, depending on which source one believes. Latvia, Lithuania, and Estonia converted around 1915, during the German occupation; Romania and Yugoslavia made the change in 1919. Russia waited until 1918, after the Bolshevik Revolution, but had to drop 13 days - February 1-13 - to make up for the accumulation of days by which, the Julian calendar was in error 336 years after the Gregorian reform. Greece did not reform its ivil calendar until 1924.
Page 231.
In Asia, Japan adopted the Gregorian calendar in 1873, during the Westernization period of the Meiji emperors.
Page 231.
China resisted until 1912, though the Gregorian calendar did not take hold throughout that country until the victory of the Communists in 1949.
Page 231.
Since 1972, when the atomic net went online, the Coordinated Universal Time - CUT - has been measured not by the motion of the earth in space but by the oscillations of the atomic level of a rare, soft, bluishgray metal called cesium.
Page 233.
In 1967 the rate of cesium’s pulse was calibrated to 9,192,631,770 oscillations per second. This is now the official measurement of world time, replacing the old standard based on the earth’s rotation and orbit, which had used as its base number a second equal to 1/31556925.9747 of a year. This means that under this new regime of Cesium, the year is no longer officially measured as 365.242199 days but as 290,091,200,500,000,000 oscillations of Cs, give or take
an oscillation or two.
Pages 233-234.
Our calendar year is linked to the year as measured between two March equinoxes, as originally established by Caesar and Sosigenes. Pope Gregory's correction in 1582 brought our calendar year within 26 seconds of the equinoctial year, where it remains today.
Page 235.
A billionth of a second translates into the space of a bout one foot for navigation.
Page 236.
These sorts of minute measurements are critical for synchronizing television feds, bouncing signals off satellites, calculating bank transfers, transmitting everything form e-mais to sonar signals in a submarine, and keeping “smart” missiles on course so they slam into an enemy’s chemical weapon’s complex instead of the middle of a populated neighorhood.
Page 236.
The “era” we use to number our years - initially called the “Christian Era” and now the “Common Era” - remains confused because there is no year zero. This means that technically century-years come in the -01 slot not -00, and millennium years happen in -001, not-000. But people prefer to celebrate the beginning of, say, the twentieth century as 1900, and the coming millennium in the year 2000, not 2001. Others complain about the awkwardness of an A.D. and B.C. timeline with “positive” and“negative” dates.
Page 238.
Time in fact begins to warp to bend noticeably at this level of precision under certain situation.
Page 236.
The Calendar of Reaon was a great improvement, but it lasted only until 1806, when Napoleon quietly reinstated the Gregorian system. The experiment did produce a number of curious watches and clocks with ten hours, and minutes divided up into decimals; and numerous books published with single-digit years.
Page 238.
As for the problem with no year zero, I know of no plans to make a correction: which at the very least would involve changing every history book dealing with dates before the year one A.D.
Page 240.
We take in stride a calendar used by most of the world that is flawed, but endures, largely because it works just fine for most of us, and it is what we are used to.
Page 241.