The retaining wall at Crown Circus was beginning to collapse due to root invasion by the surrounding trees in the gardens.  Mackenzie's contract involved removing these trees, taking down the existing sandstone walling, constructing a new reinforced concrete retaining wall and facing the new wall with a mixture of the existing sandstone and new sandstone machine cut to 75mm thick.

New copes were also fitted on top of the wall and a new cast railing manufactured, since the previous railing had been removed and melted down for gunmetal during the war.  The Client was the Crown Circus Residents Association who appointed Babtie as Engineer for the works that were partly funded by Scottish National Heritage (Glasgow).