The Berber calendar is the agricultural calendar traditionally used by Berbers. It is known as the fellaḥi; the calendar is utilized to regulate the seasonal agricultural works. The Islamic calendar, a lunar calendar, is not suited for agriculture because it does not relate to seasonal cycles. In other parts of the Islamic world either Iranian solar calendars, the Coptic calendar, the Rumi calendar, or other calendars based on the Julian calendar, were used before the introduction of the Gregorian calendar; the current Berber calendar is a legacy of the Roman province of Mauretania Caesariensis and the Roman province of Africa, as it is a surviving form of the Julian calendar. The latter calendar was used in Europe before the adoption of the Gregorian calendar, with month names derived from Latin. Berber populations used various indigenous calendars, such as that of the Guanche autochthones of the Canary Islands; however little is known of these ancient calendrical systems. The agricultural Berber calendar still in use is certainly derived from the Julian calendar, introduced in the Roman province of Africa at the time of Roman domination.
The names of the months of this calendar are derived from the corresponding Latin names and races of the Roman calendar denominations of Kalends and Ides exist: El Qabisi, an Islamic jurisconsult by Kairawan who lived in the 11th century, condemned the custom of celebrating "pagans'" festivals and cited, among traditional habits of North Africa, that of observing January Qalandas. The length of the year and of the individual months is the same as in the Julian calendar: three years of 365 days followed by a leap year of 366, without exceptions, 30- and 31-day months, except for the second one that has 28 days; the only slight discrepancy lies in that the extra day in leap years is not added at the end of February, but at the end of the year. This means that the beginning of the year corresponds to the 14th day of January in the Gregorian calendar, which coincides with the offset accumulated during the centuries between astronomical dates and the Julian calendar. In addition to the subdivision by months, within the traditional agricultural calendar there are other partitions, by "seasons" or by "strong periods", characterized by particular festivals and celebrations.
Not all the four seasons have retained a Berber denomination: the words for spring and autumn are used everywhere, more sparingly the winter and, among northern Berbers, the Berber name for the autumn has been preserved only in Jebel Nafusa. Spring tafsut – Begins on 15 furar Summer anebdu – Begins on 17 mayu Autumn amwal / aməwan ( – Begins on 17 ghusht Winter tagrest - Begins on 16 numbír An interesting element is the existing opposition between two 40-day terms, one representing the coldest part of winter and one the hottest period of summer; the coldest period is made up by 20 "white nights", from 12 to 31 dujamber, 20 "black nights", beginning on the first day of yennayer, corresponding to the Gregorian 14 January. The first day of the year is celebrated in various ways in the different parts of North Africa. A widespread tradition is a meal with particular foods. In some regions, it is marked by the sacrifice of an animal. In Algeria, such a holiday is celebrated by many people who don't use the Berber calendar in daily life.
A characteristic trait of this festivity, which blurs with the Islamic Day of Ashura, is the presence, in many regions, of ritual invocations with formulas like bennayu, babiyyanu, bu-ini, etc. Such expressions, according to many scholars, may be derived from of the ancient bonus annus wishes. A curious aspect of the Yennayer celebrations concerns the date of New Year's Day. Though once this anniversary fell everywhere on 14 January, because of a mistake introduced by some Berber cultural associations active in recovering customs on the verge of extinction, at present in a wide part of Algeria it is common opinion that the date of "Berber New Year's Day" is 12 January and not the 14th; the celebration at the 12, two days before the traditional one, it had been explicitly signaled in the city of Oran. El Azara is the period of the year extending, according to the Berber calendar, from 3 to 13 February and known by a climate sometimes hot, sometimes cold. Before the cold ends and spring begins there is a period of the year, feared.
It consists of ten days straddling the months of furar and mars, it is characterised by strong winds. It is said that, during this term, one should suspend many activities, should not marry nor go out during the night, leaving instead full scope to mysterious powers, which in that period are active and celebrate their weddings. Due to a linguistic taboo, in Djerba these creatures are called imbarken, i.e. "the blessed ones", whence this period takes its name. Jamrat el Ma, "embers of the sea", 27 February, is marked by a rise in sea temperature. Jamrat el Trab, "land embers" in English, is the period from 6 to 10 March and known to be marked by a mixture of heavy rain and sunny weather. Jamrat or coal is a term used t
Balinese saka calendar
The Balinese saka calendar is one of two calendars used on the Indonesian island of Bali. Unlike the 210-day pawukon calendar, it is based on the phases of the Moon, is the same length as the Gregorian year. Based on a lunar calendar, the saka year comprises sasih, of 30 days each. However, because the lunar cycle is shorter than 30 days, the lunar year has a length of 354 or 355 days, the calendar is adjusted to prevent it losing synchronization with the lunar or solar cycles; the months are adjusted by allocating two lunar days to one solar day every 9 weeks. This day is called ngunalatri, Sanskrit for "minus one night". To stop the Saka from lagging behind the Gregorian calendar – as happens with the Islamic calendar, an extra month, known as an intercalary month, is added after the 11th month, or after the 12th month; the length of these months is calculated according to the normal 63-day cycle. An intercalary month is added whenever necessary to prevent the final day of the 7th month, known as Tilem Kapitu, from falling in the Gregorian month of December.
The names the twelve months are taken from a mixture of Old Balinese and Sanskrit words for 1 to 12, are as follows: Kasa Karo Katiga Kapat Kalima Kanem Kapitu Kawalu Kasanga Kadasa Jyestha SadhaEach month begins the day after a new moon and has 15 days of waxing moon until the full moon 15 days of waning, ending on the new moon. Both sets of days are numbered 1 to 15; the first day of the year is the day after the first new moon in March. Note, that Nyepi falls on the first day of Kadasa, that the years of the Saka era are counted from that date; the calendar is 78 years behind the Gregorian calendar, is calculated from the beginning of the Saka Era in India. It is used alongside the 210-day Balinese pawukon calendar, Balinese festivals can be calculated according to either year; the Indian saka calendar was used for royal decrees as early as the ninth century CE. The same calendar was used in Java until Sultan Agung replaced it with the Javanese calendar in 1633; the Balinese Hindu festival of Nyepi, the day of silence, marks the start of the Saka year.
Tilem Kepitu, the last day of the 7th month, is known as Siva Ratri, is a night dedicated to the god Shiva. Devotees stay up all meditate. There are another 24 ceremonial days in the Saka year celebrated at Purnama. Eiseman, Fred B. Jr, Bali: Sekalia and Niskala Volume I: Essays on Religion and Art pp 182–185, Periplus Editions, 1989 ISBN 0-945971-03-6 Haer, Debbie Guthrie. ISBN 981 3018 496 Hobart, Angela. ISBN 0 631 17687 X Ricklefs, M. C.
The Islamic, Muslim, or Hijri calendar is a lunar calendar consisting of 12 lunar months in a year of 354 or 355 days. It is used to determine the proper days of Islamic holidays and rituals, such as the annual period of fasting and the proper time for the pilgrimage to Mecca; the civil calendar of all countries where the religion is predominantly Muslim is the Gregorian calendar. Notable exceptions to this rule are Afghanistan, which use the Solar Hijri calendar. Rents and similar regular commitments are paid by the civil calendar; the Islamic calendar employs the Hijri era whose epoch was established as the Islamic New Year of 622 AD/CE. During that year and his followers migrated from Mecca to Yathrib and established the first Muslim community, an event commemorated as the Hijra. In the West, dates in this era are denoted AH in parallel with the Christian and Jewish eras. In Muslim countries, it is sometimes denoted as H from its Arabic form. In English, years prior to the Hijra are reckoned as BH.
The current Islamic year is 1440 AH. In the Gregorian calendar, 1440 AH runs from 11 September 2018 to 30 August 2019. For central Arabia Mecca, there is a lack of epigraphical evidence but details are found in the writings of Muslim authors of the Abbasid era. Inscriptions of the ancient South Arabian calendars reveal the use of a number of local calendars. At least some of these South Arabian calendars followed the lunisolar system. Both al-Biruni and al-Mas'udi suggest that the ancient Arabs used the same month names as the Muslims, though they record other month names used by the pre-Islamic Arabs; the Islamic tradition is unanimous in stating that Arabs of Tihamah and Najd distinguished between two types of months and forbidden months. The forbidden months were four months during which fighting is forbidden, listed as Rajab and the three months around the pilgrimage season, Dhu al-Qa‘dah, Dhu al-Hijjah, Muharram. Information about the forbidden months is found in the writings of Procopius, where he describes an armistice with the Eastern Arabs of the Lakhmid al-Mundhir which happened in the summer of 541 AD/CE.
However, Muslim historians do not link these months to a particular season. The Qur'an links the four forbidden months with Nasī’, a word that means "postponement". According to Muslim tradition, the decision of postponement was administered by the tribe of Kinanah, by a man known as the al-Qalammas of Kinanah and his descendants. Different interpretations of the concept of Nasī’ have been proposed; some scholars, both Muslim and Western, maintain that the pre-Islamic calendar used in central Arabia was a purely lunar calendar similar to the modern Islamic calendar. According to this view, Nasī’ is related to the pre-Islamic practices of the Meccan Arabs, where they would alter the distribution of the forbidden months within a given year without implying a calendar manipulation; this interpretation is supported by Arab historians and lexicographers, like Ibn Hisham, Ibn Manzur, the corpus of Qur'anic exegesis. This is corroborated by an early Sabaic inscription, where a religious ritual was "postponed" due to war.
According to the context of this inscription, the verb ns'’ has nothing to do with intercalation, but only with moving religious events within the calendar itself. The similarity between the religious concept of this ancient inscription and the Qur'an suggests that non-calendaring postponement is the Qur'anic meaning of Nasī’; the Encyclopaedia of Islam concludes "The Arabic system of can only have been intended to move the Hajj and the fairs associated with it in the vicinity of Mecca to a suitable season of the year. It was not intended to establish a fixed calendar to be observed." The term "fixed calendar" is understood to refer to the non-intercalated calendar. Others concur that it was a lunar calendar, but suggest that about 200 years before the Hijra it was transformed into a lunisolar calendar containing an intercalary month added from time to time to keep the pilgrimage within the season of the year when merchandise was most abundant; this interpretation was first proposed by the medieval Muslim astrologer and astronomer Abu Ma'shar al-Balkhi, by al-Biruni, al-Mas'udi, some western scholars.
This interpretation considers Nasī’ to be a synonym to the Arabic word for "intercalation". The Arabs, according to one explanation mentioned by Abu Ma'shar, learned of this type of intercalation from the Jews; the Jewish Nasi was the official. Some sources say that the Arabs followed the Jewish practice and intercalated seven months over nineteen years, or else that they intercalated nine months over 24 years. Postponement of one ritual in a particular circumstance does not imply alteration of the sequence of months, scholars agree that this did not happen. Al-Biruni says this did not happen, the festivals were kept within their season by intercalation every second or third year of a month between Dhu al-Hijjah and Muharram, he says that, in terms of the fixed calendar, not introduced until 10 AH, the first intercalation was, for example, of a month between Dhu al-Hijjah and Muharram, the second of a month between Muharram and Safar, the third of a month between Safar and Rabi'I, so on. The intercalations were arranged.
The notice of interca
Ab urbe condita
Ab urbe condita, or Anno urbis conditæ abbreviated as AUC in either case, is a convention, used in antiquity and by classical historians to refer to a given year in Ancient Rome. Ab urbe condita means "from the founding of the City," while anno urbis conditæ means "in the year since the City's founding." Therefore, the traditional year of the foundation of Rome, 753 BC, would be written AUC 1, while AD 1 would be AUC 754. The foundation of the Empire in 27 BC would be AUC 727. Usage of the term was more common during the Renaissance, when editors sometimes added AUC to Roman manuscripts they published, giving the false impression that the convention was used in antiquity. In reality, the dominant method of identifying years in Roman times was to name the two consuls who held office that year. In late antiquity, regnal years were in use, as was the Diocletian era in Roman Egypt after AD 293, in the Byzantine Empire after AD 537, following a decree by Justinian; the traditional date for the founding of Rome, 21 April 753 BC, is due to Marcus Terentius Varro.
Varro may have used the consular list and called the year of the first consuls "ab urbe condita 245," accepting the 244-year interval from Dionysius of Halicarnassus for the kings after the foundation of Rome. The correctness of this calculation has not been confirmed. From the time of Claudius onward, this calculation superseded other contemporary calculations. Celebrating the anniversary of the city became part of imperial propaganda. Claudius was the first to hold magnificent celebrations in honor of the anniversary of the city, in AD 48, the eight hundredth year from the founding of the city. Hadrian and Antoninus Pius held similar celebrations, in AD 121, in AD 147 and AD 148, respectively. In AD 248, Philip the Arab celebrated Rome's first millennium, together with Ludi saeculares for Rome's alleged tenth sæculum. Coins from his reign commemorate the celebrations. A coin by a contender for the imperial throne, explicitly states "ear one thousand and first", an indication that the citizens of the empire had a sense of the beginning of a new era, a Sæculum Novum.
The Anno Domini year numbering was developed by a monk named Dionysius Exiguus in Rome in AD 525, as a result of his work on calculating the date of Easter. Dionysius did not use the AUC convention, but instead based his calculations on the Diocletian era; this convention had been in use since AD 293, the year of the tetrarchy, as it became impractical to use regnal years of the current emperor. In his Easter table, the year AD 532 was equated with the 248th regnal year of Diocletian; the table counted the years starting from the presumed birth of Christ, rather than the accession of the emperor Diocletian on 20 November AD 284, or as stated by Dionysius: "sed magis elegimus ab incarnatione Domini nostri Jesu Christi annorum tempora praenotare". Blackburn and Holford-Strevens review interpretations of Dionysius which place the Incarnation in 2 BC, 1 BC, or AD 1, it has been calculated that the year AD 1 corresponds to AUC 754, based on the epoch of Varro. Thus, AUC 1 = 753 BC AUC 753 = 1 BC AUC 754 = AD 1 AUC 1000 = AD 247 AUC 1229 = AD 476 AUC 2206 = AD 1453 AUC 2753 = AD 2000 AUC 2772 = AD 2019 List of Latin phrases
The 4th century was the time period which lasted from 301 to 400. In the West, the early part of the century was shaped by Constantine the Great, who became the first Roman emperor to adopt Christianity. Gaining sole reign of the empire, he is noted for re-establishing a single imperial capital, choosing the site of ancient Byzantium in 330 to build the city soon called Nova Roma; the last emperor to control both the eastern and western halves of the empire was Theodosius I. As the century progressed after his death it became apparent that the empire had changed in many ways since the time of Augustus; the two emperor system established by Diocletian in the previous century fell into regular practice, the east continued to grow in importance as a centre of trade and imperial power, while Rome itself diminished in importance due to its location far from potential trouble spots, like Central Europe and the East. Late in the century Christianity became the official state religion, the empire's old pagan culture began to disappear.
General prosperity was felt throughout this period, but recurring invasions by Germanic tribes plagued the empire from AD 376 onward. These early invasions marked the beginning of the end for the Western Roman Empire. In China, the Jin dynasty, which had united the nation prior in 280, began to face troubles by the start of the century due to political infighting, which led to the opportunistic insurrections of the northern barbarian tribes, which overwhelmed the empire, forcing the Jin court to retreat and entrench itself in the south past the Yangtze river, starting what is known as the Eastern Jin dynasty around 317. Towards the end of the century, Emperor of the Former Qin, Fu Jiān, united the north under his banner, planned to conquer the Jin dynasty in the south, so as to reunite the land, but was decisively defeated at the Battle of Fei River in 383, causing massive unrest and civil war in his empire, thereby leading to the fall of the Former Qin, the continued existence of the Eastern Jin dynasty.
According to archaeologists, sufficient archaeological correlates of state-level societies coalesced in the 4th century to show the existence in Korea of the Three Kingdoms of Baekje and Silla. Historians of the Roman Empire may refer to the "Long Fourth Century", the period spanning the fourth century proper, but starting earlier with the accession of the emperor Diocletian in 284 and ending with the death of Honorius in 423 or of Theodosius II in 450. Noba people settle in Africa. Early 4th century – Former audience hall now known as the Basilica, Germany, is built. 301: Armenia first to adopt Christianity as state religion. 306 – 337: Constantine the Great, ends persecution of Christians in the Roman Empire and Constantinople becomes new seat of government. 325 – 328: The Kingdom of Aksum adopts Christianity. 325: Constantine the Great calls the First Council of Nicaea to pacify Christianity in the grip of the Arian controversy. 335 – 380: Samudragupta expands the Gupta Empire. 337: Constantine the Great is baptized on his death bed.
350: About this time the Kingdom of Aksum conquers the Kingdom of Kush. 350 – 400: At some time during this period, the Huns began to attack the Sassanid Empire. 350: The Kutai Martadipura phase in East Kalimantan produced the earliest known stone inscriptions in Indonesia. 365: an earthquake with a magnitude of at least eight strikes the Eastern Mediterranean. The following tsunami causes widespread destruction in Crete, Libya, Egypt and Sicily. Mid-4th century – Dish, from Mildenhall, England, is made, it is now kept at London. Mid-4th century – Wang Xizhi makes a portion of a letter from the Feng Ju album. Six Dynasties period, it is now kept at National Palace Museum, Taiwan, Republic of China. 376: Visigoths appear on the Danube and are allowed entry into the Roman Empire in their flight from the Huns. 378: Battle of Adrianople: Roman army is defeated by the Visigoth cavalry. Emperor Valens is killed. 378 – 395: Theodosius I, Roman emperor, bans pagan worship, Christianity is made the official religion of the Empire.
378: Siyaj K'ak' conquers Waka on January 8. 378: Siyaj K'ak' conquers Tikal on January 16. 378: Siyaj K'ak' conquers Uaxactun. 381: First Council of Constantinople reaffirms the Christian doctrine of the Trinity by adding to the creed of Nicaea. 383: Battle of Fei River in China. 395: The Battle of Canhe Slope occurs. 395: Roman Emperor Theodosius I dies, causing the Roman Empire to split permanently. Late 4th century – See "The Historia" of Arbogast and Bauto. Late 4th century – Cubiculum of Leonis, Catacomb of Commodilla, near Rome, is made. Late 4th century – Atrium added in Old St. Peter's Basilica, Rome. Aelia Eudoxia, Roman Empress. Alaric I, King of the Visigoths Albia Dominica, Roman Empress and regent. Arbogast, Roman general and rebel. Arcadius, Roman Emperor. Atlatl Cauac, ruler of Teotihuacan Bassianus, Roman candidate for the position of Caesar. Calocaerus, Roman usurper. Chak Tok Ich'aak I reign 14th dynastic ruler of Tikal Chandragupta I, Gupta emperor Chandragupta II, Gupta emperor Claudius Silvanus, Roman general and usurper.
Constans, Roman Emperor. Constantina, Roman Augusta (between 307 and
The Byzantine calendar called "Creation Era of Constantinople" or "Era of the World", was the calendar used by the Eastern Orthodox Church from c. 691 to 1728 in the Ecumenical Patriarchate. It was the official calendar of the Byzantine Empire from 988 to 1453, of Kievan Rus' and Russia from c. 988 to 1700. Since "Byzantine" is a historiographical term, the original name uses the noun "Roman" as it was how the Eastern Roman Empire continued calling itself; the calendar was based on the Julian calendar, except that the year started on 1 September and the year number used an Anno Mundi epoch derived from the Septuagint version of the Bible. It placed the date of creation at 5509 years before the Incarnation, was characterized by a certain tendency, a tradition among Jews and early Christians to number the years from the calculated foundation of the world, its Year One, marking the supposed date of creation, was September 1, 5509 BC, to August 31, 5508 BC. It is not known when; the first appearance of the term is in the treatise of a certain "monk and priest", who mentions all the main variants of the "World Era" in his work.
Georgios argues that the main advantage of the World era is the common starting point of the astronomical lunar and solar cycles, of the cycle of indictions, the usual dating system in Byzantium since the 6th century. He already regards it as the most convenient for the Easter computus. Complex calculations of the 19-year lunar and 28-year solar cycles within this world era allowed scholars to discover the cosmic significance of certain historical dates, such as the birth or the crucifixion of Jesus; this date underwent minor revisions before being finalized in the mid-7th century, although its precursors were developed c. AD 412. By the second half of the 7th century, the Creation Era was known in Western Europe, at least in Great Britain. By the late 10th century around AD 988, when the era appears in use on official government records, a unified system was recognized across the Eastern Roman world; the era was calculated as starting on September 1, Jesus was thought to have been born in the year 5509 since the creation of the world.
Historical time was thus calculated from the creation, not from Christ's birth, as in the west after the Anno Domini system was adopted between 6th and 9th centuries. The Eastern Church avoided the use of the Anno Domini system of Dionysius Exiguus, since the date of Christ's birth was debated in Constantinople as late as the 14th century. Otherwise the Byzantine calendar was identical to the Julian Calendar except that: the names of the months were transcribed from Latin into Greek; the leap day of the Byzantine calendar was obtained in an identical manner to the bissextile day of the original Roman version of the Julian calendar, by doubling the sixth day before the calends of March, i.e. by doubling 24 February. The Byzantine World Era was replaced in the Orthodox Church by the Christian Era, utilized by Patriarch Theophanes I Karykes in 1597, afterwards by Patriarch Cyril Lucaris in 1626, formally established by the Church in 1728. Meanwhile, as Russia received Orthodox Christianity from Byzantium, she inherited the Orthodox Calendar based on the Byzantine Era.
After the collapse of the Byzantine Empire in 1453, the era continued to be used by Russia, which witnessed millennialist movements in Moscow in AD 1492. It was only in AD 1700 that the Byzantine World Era in Russia was changed to the Julian Calendar by Peter the Great, it still forms the basis of traditional Orthodox calendars up to today. September AD 2000 began the year 7509 AM; the earliest extant Christian writings on the age of the world according to the Biblical chronology are by Theophilus, the sixth bishop of Antioch from the Apostles, in his apologetic work To Autolycus, by Julius Africanus in his Five Books of Chronology. Both of these early Christian writers, following the Septuagint version of the Old Testament, determined the age of the world to have been about 5,530 years at the birth of Christ. Ben Zion Wacholder points out that the writings of the Church Fathers on this subject are of vital significance, in that through the Christian chronographers a window to the earlier Hellenistic biblical chronographers is preserved: An immense intellectual effort was expended during the Hellenistic period by both Jews and pagans to date creation, the flood, building of the Temple...
In the course of their studies, men such as Tatian of Antioch, Clement of Alexandria, Hippolytus of Rome
Indian national calendar
The Indian national calendar, sometimes called the Shalivahana Shaka calendar. It is used, alongside the Gregorian calendar, by The Gazette of India, in news broadcasts by All India Radio and in calendars and communications issued by the Government of India; the Saka calendar is used in Java and Bali among Indonesian Hindus. Nyepi, the "Day of Silence", is a celebration of the Saka new year in Bali. Nepal's Nepal Sambat evolved from the Saka calendar. Prior to colonization, the Philippines used to apply the Saka calendar as well as suggested by the Laguna Copperplate Inscription; the term may ambiguously refer to the Hindu calendar. The historic Shalivahana era calendar is still used, it has years. The calendar months follow the signs of the tropical zodiac rather than the sidereal zodiac used with the Hindu calendar. Chaitra has 30 days and starts on March 22, except in leap years, when it has 31 days and starts on March 21; the months in the first half of the year all have 31 days, to take into account the slower movement of the sun across the ecliptic at this time.
The names of the months are derived from older, Hindu lunisolar calendars, so variations in spelling exist, there is a possible source of confusion as to what calendar a date belongs to. Years are counted in the Saka era. To determine leap years, add 78 to the Saka year – if the result is a leap year in the Gregorian calendar the Saka year is a leap year as well, its structure is just like the Persian calendar. Senior Indian Astrophysicist Meghnad Saha was the head of the Calendar Reform Committee under the aegis of the Council of Scientific and Industrial Research. Other members of the Committee were: A. C. Banerjee, K. K. Daftari, J. S. Karandikar, Gorakh Prasad, R. V. Vaidya and N. C. Lahiri, it was Saha's effort. The task before the Committee was to prepare an accurate calendar based on scientific study, which could be adopted uniformly throughout India, it was a mammoth task. The Committee had to undertake a detailed study of different calendars prevalent in different parts of the country. There were thirty different calendars.
The task was further complicated by the fact that religion and local sentiments were integral to those calendars. India's first prime minister, Jawaharlal Nehru, in his preface to the Report of the Committee, published in 1955, wrote: “They represent past political divisions in the country.... Now that we have attained Independence, it is desirable that there should be a certain uniformity in the calendar for our civic and other purposes, this should be done on a scientific approach to this problem.” Usage started at 1 Chaitra 1879, Saka Era, or 22 March 1957. Report of the Calendar Reform Committee – online link. Mapping Time: The Calendar and its History by E. G. Richards, 1998, pp. 184–185. Calendars and their History Indian Calendars Positional astronomy in India Indian National Calendar abstract