Jonathan Hathaway was born in 1672 per his gravestone. He died during his 56th year, meaning he was 55 years of age when he died during an epidemic in Dartmouth, Massachusetts on 17 Sep 1727. Subtracting 55 years from 1727 verifies his year of birth as 1672. However, in 1672 the Julian Calendar was in use, meaning that the year started on March 25th & ended on March 24th. The change to the Gregorian calender did not take place until 1752 well after Jonathan's 17 Sep 1727 death. The Julian calendar was in use during Jonathan's entire lifespan... therefore using his age at death as 55 to calculate had possible date of birth he would have been born between 17 Sep 1672 & 24 Mar 1672 per the Julian calendar or bet. 17 Sep 1672 & 24 Mar 1673 per the Gregorian calendar. Incidentally, the Gregorian calendar is still in use today.