I would like therefore to take this opportunity to introduce you to Archibald Smith's swing door centre/top pivot/top centre. This particular top centre was introduced to overcome the "evil" of wear which leads to the drooping of doors at the top and the "annoyance" of swing doors banging together as can be read in the above (those Victorians thought of everything). The article is from around 1872 as are the top pivots below which have worn extremely well for their age.
Link to article from The Architect magazine 1872:
https://books.google.co.uk/books?id=_8vSInOb4k8C&pg=PA15&dq=archibald+smith+and+co%27s+adjustable+top+centre&hl=en&sa=X&ved=0ahUKEwig1MfE7KPbAhUHJcAKHeSkDlwQuwUIMDAB#v=onepage&q=archibald%20smith%20and%20co's%20adjustable%20top%20centre&f=false
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