Tuesday, 20 January 2015

Reforming the Calendar

We owe the origins of our modern calendar to Julius Caesar. Before his time the Roman calendar had 12 lunar months, bringing about a year of 354 days; to which one extra day was added because of the Romans' superstitious dislike of even numbers. This was of course far short of a solar year, and the solution adopted was to insert an extra month (known as an "intercalated" month) every 8 years. This was left to the priests. But important considerations were involved – the fact that the Consuls and other officials held power for just one year, or the question of when debts were due to be paid – that the priestly power was often swayed by political considerations and personal gain. Julius Caesar as Pontifex Maximus was a particular offender: when he returned to Rome from his wars in 46 BC the Roman calendar was a full two months adrift!

It seems quite likely that Caesar got his idea for calendar reform from his time in Egypt, in 48 BC. Alexandria was the intellectual centre of the Hellenistic world. The great astronomer and mathematician Hipparchus, around 130 BC, had calculated the true length of the solar year as a fraction under 365 ¼ days. Caesar accepted the figure of 365 ¼, and did not bother with the few minutes' inaccuracy involved: a cause of trouble in later centuries. (It was Hipparcus who first divided the day into 24 hours, based on the rising of the sun at the equinox – 6 hours sunrise to noon, 6 more noon to sunset. A later Alexandrian, Claudius Ptolemy, c.137 A.D., divided each hour into 60 seconds. The Romans timed the day from midnight, as we do nowadays, unlike other peoples, who began it at sunrise or sunset)
     Caesar inserted two months of 33 and 34 days between November and December, as well as another already installed in February, thus giving an extraordinary year of 445 days! This came to be known as “The year of confusion” – “annus confusionis”. He added 10 days to the year, with a leap year every 4 years, and reorganized the months to have alternately 30 and 31 days, with the exception of February, which had 29 days, with an extra leap year day every 4 years. The start of the year was moved to January 1st (It is not clear why; possibly because it comes just after the winter solstice) So when the Romans woke up on January 1st, 45 BC, they were starting a new calendar! After Caesar’s death, the month Quintilius was renamed in his honour, becoming July.
     This was not quite the end, however, because during the reign of his successor, Augustus, a servile senate decided to rename the month Sextilis as August, and to give it 31 days, so as not to be shorter than July! To achieve this, a day was taken from February, and to avoid having three 31-day months in a row, the numbers of days in September to December were switched round. We should be grateful that the next Emperor, Tiberius, refused to follow this tradition. When the Senate proposed renaming September after him, the cynical old Emperor retorted, “What happens if there are thirteen Caesars?” and the idea was dropped. Nero tried to rename April after himself, but this was quickly abandoned after his death. 
     The other Roman months retained their old names, with an odd result. Every student of Latin must have been puzzled to find that the months September, October, November and December clearly mean numbers 7-8-9-10, whereas they are numbers 9-10-11-12 in the calendar. This refers back to the very early days of Rome,when there were only ten months in the year. 

Starting the year on January 1st was not to be universally followed. In mediaeval England, for instance, the New Year began on March 25th: the Feast of the Annunciation, which is also very close to the spring equinox. In France, the New Year began at Easter; in Russia it began in September.

So we had the Julian calendar, which was to dominate Europe for the next 500 years, despite the fact that it was not entirely accurate. The other issue which was resolved in Roman times was the question of dating. Traditionally the Romans counted their years from the legendary founding of the city in 753 BC, but it was more usual to name the years by political changes: e.g. “The year in which Marcellus and Bibulus were consuls”. After the empire was established, events could be dated “in the third year of the emperor Nero”, or whatever. This was actually a reversion to a much more ancient system; dating events to a certain year of a king’s reign, which we find in ancient Mesopotamia and Egypt. (This was in Britain the official way of dating Acts of Parliament: “The third Act passed in the fifth year of the reign of George III” etc)
     In the 6th century, a Christian called Dionysus calculated that Christ had been born 531 years ago, and established this as his base: Year 1. (There was no Year Zero: a point which emerged in debates about whether the millennium should be celebrated in 2000 or 2001). Thus the concepts of A.D. and B.C. were established. Bede was the first significant historian to use Dionysus’s system.
     Unfortunately, Dionysus’s calculations were not quite right. The problem is the appearance of King Herod in St Matthew’s gospel, since calculations from Roman dating show that Herod died in 4 BC! Luke gives only the vaguest dating ("decree from Caesar Augustus" …… "when Cyrenius was governor of Syria") which certainly implies that Palestine was no longer a client kingdom under Herod. Neither the other two gospels, nor the Book of Acts nor Paul’s Epistles make any attempt to date the nativity, or indeed anything else.  One suspects that the ancient writers had no real interest in precise dating. It should have been possible to at least estimate a date, if not for the nativity,.then certainly for the Crucifixion – “the 14th year of the emperor Tiberius” perhaps? To a modern historian, it is astonishing that not a single early Christian writer attempted to do this – but they just didn’t think that way in those days!

            The Gregorian Calendar

Hipparchus had known that the year was not exactly 365 ¼ days long, and by the 13th century European scholars like Roger Bacon were pointing out that the calendar was in fact gradually drifting into inaccuracy – the years were slightly too long, so that the equinoxes and solstices were now a few days out. This meant they were celebrating Easter on the wrong date!
      The first official call for calendar reform came from Pope Clement VI in an epistle of 1344 – but other problems caused this to fall on deaf ears. Pope Clement was not even based in Rome, but in Avignon, where a succession of popes were little more than puppets of the King of France: then for half a century there were two competing popes: one in Avignon and one back in Rome, and for a while there were three! Immediately after Clement’s epistle, before any calendar reform could begin, the Black Death arrived in Europe. The Hundred Years’ War began. A century later, new lands began to be discovered in the far East and across the Atlantic. Copernicus speculated on a heliocentric system. The Reformation began (and Luther denounced the Copernican system, as clearly contrary to scripture) The papacy never completely forgot the question of calendar reform, but nothing actually happened. 

The man who finally bit the bullet was Ugo Buoncompagni, an ecclesiastical lawyer from a Roman noble family, who at the age of 70 became Pope Gregory XIII in 1572. During his reign of 13 years he established the Index of banned books, rejoiced at the slaughter of thousands of Protestants in the St. Bartholomew’s day massacre in Paris, and attempted to organize the overthrow of Queen Elizabeth of England; but he also issued a Papal Bull setting up a commission, consisting mostly of priests who were also astronomers, mathematicians and scientists, to suggest reform of the calendar.  
    In view of the controversy between the Ptolemaic and Copernican theories, the committee wisely ignored the whole issue. They decided the mean length of the year was 365 days, 5 hours, 49 minutes and 12 seconds (actually 26 seconds out, according to modern atomic clocks). The Julian calendar would be rectified by omitting three leap year days every 400 years (it should actually be every 402 years) The way this would work would be that there would be a leap year in 1600 and 2000, but not in 1700, 1800 and 1900. (There will not be a leap year in 2100, and after that it won't concern us!) Such a calendar would only be out by one day in 3,300 years.
      The current calendar was 10 days out. It could have been rectified in stages, but instead it was decided to take the bold step of jumping 10 days ahead in one go. The New Year, when the date changed, should now always be January 1st, following the Roman system. In 1578 the proposals were circulated to the kings and scholars of Europe for discussion. Many agreed, but others, especially in the Protestant countries, did not. Philip II of Spain insisted that the spring equinox should always be deemed to be on March 21st, to make the calculation of Easter a little easier. The Bull to reform the calendar was issued in early 1582, and was implemented on January 1st 1583, with the date jumping forward 10 days from October 4th (this being the time with fewest saints’ days)
     But the new Gregorian calendar was not universally accepted. Almost all the major Catholic states went over to the new calendar in the next couple of years, and duly jumped ten days forward, but to the Protestant states: England, Holland, the Scandinavian kingdoms, parts of Germany and Switzerland; the new calendar was “Popish” and thus suspect. So in England, for instance, the date was still 10 days behind, and the New Year continued to be on March 25th. This has been an annoyance to historians ever since, starting with the Spanish Armada in 1588. What happens is that historians have to tell their readers whether the dates they use are Gregorian, or “New Style” (NS) or Julian: “Old Style” (OS)

Reforming the English calendar had to wait. In the 17th century, proposals for reform were opposed by both the Church of England and the Puritans, despite it being pointed out that the method for calculating the date of Easter was now highly erroneous. By the 18th century the Julian calendar was now 11 days out (since the Gregorian system had a leap year in 1600, but not in 1700). Meanwhile Edward Halley had calculated the length of the year as 365 days, 5 hours, 48 minutes and 55 seconds.

     In 1751 a literary nobleman, Philip Stanhope, Earl of Chesterfield (who had briefly been a cabinet minister, and is best remembered nowadays for his series of letters to his illegitimate son, instructing him how to behave in polite society), introduced in the House of Lords a Bill “For regulating the commencement of the year, and for correcting the calendar now in use”. Henry Pelham, the Prime Minister (1743-54) was a naturally cautious man, and his brother the Duke of Newcastle, the Secretary of State, who was considered by most contemporaries to be an imbecile, was thrown into a tizzy, but Chesterfield’s Bill met little opposition, sailed through Parliament and was signed into law in May. (Stanhope admitted privately that he had baffled the Lords with his seeming erudition on the mathematics and astronomy and history of calendars, about which he actually knew very little!)
     So in September 1752, Wednesday 2nd was immediately followed by Thursday 14th. It was enacted that the missing days had no legal existence for the purpose of wages, interest earned, contracts or prison sentences etc: everyone would have to wait until the number of “natural days” had been accumulated. It was all carefully explained to the public in official publications and newspapers, including such publications as “The Ladies’ Diary”. Even so, there were protests: mobs came out on the streets in London and other towns, shouting “Give us back our 11 days!” In rioting in Bristol, people were killed! And despite the fact that the Church of England officially approved of the changes, the contemporary historian Archdeacon Coxe, in his book on Henry Pelham’s government, tells us that:-
“Greater difficulty was, however, found in appeasing the clamour of the people against the supposed profaneness of changing the saints’ days in the calendar, and altering the time of all immovable feasts”. Some people obstinately celebrated Christmas on what was now officially January 5th.

     The Russians stuck with the Julian calendar throughout the 19th century. After 1900 it was 13 days out, so that the October Revolution which brought the Bolsheviks to power actually took place in November! It was left to Lenin to impose the Gregorian calendar on Russia, but the Orthodox Church refused to acknowledge it, and continued to hold its holy days on the old dates. 

    On January 1st 1753 in Britain, the date of the year officially changed. But the financial year still began on March 25th, and still does – the old March 25th; plus, of course, 11 days! 

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