fixed calendar - unified gregorian calendar ebook

The calendar we use today is basically the Julian calendar – introduced in 45 BC by Julius Caesar. In 1582 Pope Gregory XIII made only a minor amendment to this calendar concerning leap years in order to prevent the calendar from lagging behind the solar year by 1 day in every 128 years – minimising this error to 1 day in every 3322 years. When it was first created, there were only two versions of...