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Two long mean surface air temperature series are presented for Armagh Observatory; one based on twice daily spot temperature readings, 1796-1882, and the other on daily maximum and minimum temperatures, 1844-1992. Our data confirm the correlation of temperature with solar cycle length, first suggested by Friis-Christensen and Lassen (Science 254, 698, 1991) and, for this site, extend their result a further 65 years, back to the end of the 18th century.