The stone for Elizabeth Waters lists the date of death as February 10 in the year 1698 / 9. Dual-year dating occurred during a transition period when the Gregorian Calendar was replacing the Julian Calendar.
At different times and in different places throughout history, different calendars have been in use. A forerunner of our modern calendar is the one promulgated by Julius Caesar. Known as the Julian Calendar, it had 365.25 days as the average length of a year. This calendar year differed from the actual solar year by about eleven minutes per year. As a result, over the centuries, the error accumulated and the calendar became more and more out of sync with the seasons. The discrepancy created a special problem for the Roman Catholic Church since it affected the determination of the date of Easter.
Several astronomers were consulted. Pope Gregory XIII chose the calendar formulated by the Jesuit mathematician and astronomer, Christopher Clavius. On February 24, 1582, he issued a papal bull, Inter Gravissimas, which established the Gregorian Calendar Reform. Among its provisions, ten days were omitted from that year’s month of October in order to get the calendar back in sync with the solar year; the rules for leap year were changed; the position of the extra day during a leap year was made the day following February 28; and new rules for determining Easter were adopted.
Catholic European countries quickly adopted the Gregorian calendars, but it took longer for Protestant countries to follow. England and its colonies didn’t officially adopt the Gregorian calendar until 1752. By that time, the discrepancy between the Julian Calendar and the solar year had increased another day, so England had to drop eleven days from the 1752 calendar to switch over.
Another complication was the the first day of the new year. Different people celebrated it on different days: January 1, March 1, March 25, or December 25. Prior to 1752, England and the colonies began the new year on Lady Day, which was March 25. Thus, March 24, 1751, was followed by March 25, 1752. When England adopted the Gregorian Calendar in 1752, January 1 was also established as the first day of the new year. 1752 ended on December 31, and 1753 began on January 1.
This difference in dating should be taken into account when doing historical or genealogical research. For example, George Washington’s birth date was February 11, 1731, on the Julian Calendar and February 22, 1732, on the Gregorian Calendar.
In many areas, the general population continued to use the Julian Calendar long after the Gregorian Calendar had been officially adopted. To clarify dating in the 16th, 17th, and 18th Centuries, dates recorded under the Julian Calendar were marked “O.S” for “Old Style,” and dates recorded under the Gregorian Calendar were marked “N.S.” for “New Style.”
Some headstones at Old Burial Hill reflect this transitional period by using dual dates for the year of death. For example, George Bonfield’s year of death is inscribed as 1690/1, Mary Galle’s as 1694/5, and John Browne’s as 1702/3. The first year Is the year under the Julian Calendar, and the second is the year under the Gregorian Calendar.