George Washington's birthday
The Country Parson's Formula
Stonehenge and Sothis (third millennium B.C.)
Meton (432 B.C.), Callippus (330 B.C.), and Hipparchus (130 B.C.)
Constantine the Great (A.D. 321)
Dionysius Exiguus (A.D. 525)
The Synod of Whitby (A.D. 664)
The Venerable Bede (A.D. 725)
Pope Gregory XIII (A.D. 1582)
The perfect Christian calendar and God's longitude
Archbishop Ussher and the age of the earth (A.D. 1650)
Lord Chesterfield's Act (A.D. 1751)
President Arthur requests (A.D. 1884)
Marching to the same drummer?
How many days in a dinosaur year?
Should 2100 be a double leap year?
Appendix A: How long is a day?
Appendix B: How long is a year?
Appendix C: How long is a second?
Appendix D: How long is a month?
