Regarding whether 5 June or 16 June is correct for Adam Smith's baptism
may depend on whether one uses the Gregorian or Julian Calendar.
Apparently Britain shifted from the Julian to the Gregorian calendar in
1752; I say apparently because my immediate source for this is the
"notoriously unreliable" wikipedia which also indicates that Gregorian
calendar advances dates by 11 days over the Julian calendar which would
account for the discrepancy between Buchan and wikipedia.

Take away for David Colander could be that he will have decide on whether
the birth dates he lists is based on Gregorian or Julian calendar.

David Mitch