The number shown after each Act's title is its chapter number. Acts are cited using this number, preceded by the year(s) of the reign during which the relevant parliamentary session was held; thus the Union with Ireland Act 1800 is cited as "39 & 40 Geo. 3 c. 67", meaning the 67th Act passed during the session that started in the 39th year of the reign of George III and which finished in the 40th year of that reign. Note that the modern convention is to use Arabic numerals in citations (thus "41 Geo. 3" rather than "41 Geo. III"). Acts of the last session of the Parliament of Great Britain and the first session of the Parliament of the United Kingdom are both cited as "41 Geo. 3".