Depths of burials in a shared plot - how far apart?

[hurworth]

I'm going through the records of a Scottish graveyard in the early 1800s and hoping that I might find some clues about some of my ancestors.  I'm also checking monumental inscriptions that are available.  My family didn't have any headstones but the other people with the same surname who did have headstones have helped to rule out certain burials. 

Two young sisters of my ancestor were buried there in the 1820s - one at the head and the other at the foot, at 7 feet in the north plot which belongs to a man with the same surname as their mother.
 I think the plot was purchased by their uncle.

A few months before the first sister died the mother of a man with the same name as their uncle, was buried in this man's south grave at 7 feet.  Five years later the father of a man with the same name as their uncle was buried 6 foot deep in the south grave of his son's property.

From the vertical distance between these burials (6ft and 7ft) I'm not sure this is the same plot and family.  If anyone has knowledge of the practical aspects of interment I'd appreciate their opinion.

[angusg]

these distances seem quite normal.

[Guy Etchells]

I would suggest that grave depths were not precisely measured but estimated more often than not. Six feet would be the height of the grave digger plus a spades depth or perhaps a couple of spades depths further.
When adding a further burial to an existing grave they would dig until the first coffin/previous was found (this would be left with a covering of soil and the subsequent coffin laid on the top rather than measurements being taken.
The only important measurement was the depth of coverage of the burial closest to the ground level to ensure a minimum coverage.

Cheers
Guy

[hurworth]

Thank you for the information.  It's very helpful.