Septennial Act 1716 Septennial Act 1716 The Septennial Act 1716 (1 Geo 1 St 2 c 38), also known as the Septennial Act 1715, was an Act of the Parliament of Great Britain. It was passed in May 1716. It increased the maximum length of a parliament (and hence the maximum period between general elections) from three years to seven. This seven-year ceiling remained in law from 1716 until 1911. The previous limit of three years had been set by the Triennial Act 1694, enacted by the Parliament of England. The act's ostensible aim was to reduce the expense caused by frequent elections.
Metonic cycle based on the tropical year and maintain the seasons at the same calendar times each year. Nineteen tropical years are about two hours shorter than 235 synodic months. The Metonic cycle's error is, therefore, one full day every 219 years, or 12.4 parts per million. Note that the 19-year cycle is also close (to somewhat more than half a day) to 255 draconic months, so it is also an eclipse cycle, which lasts only for about 4 or 5 recurrences of eclipses. The Octon is of a Metonic cycle (47 synodic months, 3.8 years), and it recurs about 20 to