CALENDAR ACT (1751). An Act for Regulating the Commencement of the Year; and for Correcting the Calendar now in Use.

Folio (12 inches). 24 George II, Chapter 23. General title leaf + pages 571-578 + Tables and Rules (title leaf + 22 pages). Woodcut Royal coat of arms and decorative initial. Text in Black Letter. Neatly extracted from a bound volume and expertly mended. Paper evenly toned. The Act changed the calendar from the Old Style Julian Calendar to the New Style Gregorian Calendar. In Great Britain and its colonies, the New Style Gregorian Calendar was adopted in September 1752, and changed the start of the calendar year from 25 March (Day of the Annunciation) to 1 January (New Years Day and the Circumcision of Christ). As well, in order to deal with the discrepancy of eleven days that the Old Style Julian Calendar had fallen behind true astronomical time, it was ordered that Wednesday 2 September 1752 would be immediately followed by Thursday 14 September 1752. Appended to the Act is a section titled The New Calendar, Tables, and Rules, Mentioned, and Referred to, in the Act for Regulating the Commencement of the Year; and for Correcting the Calendar now in Use, which has monthly tables noting important religious events, feasts and holy-days, vigils, fasts and days of abstinence, and tables to determine Easter Day and moveable feasts for the years 1752 to 1899. The Gregorian Calendar was named after Pope Gregory XIII, who proclaimed its adoption by the Catholic church in 1582.