A memorial plaque in (the former) St Andrews Church, Henderson Road, Eastney. It is not known whether it remains in situ or has been removed.

Click image to enlarge
In memory of Colonel George
Stephen Digby, Commandant
Royal Marine Artillery, Companion of the Bath,
Knight of the Legion of Honour and of the
Medjidic, who after a distinguished career,
died on 19th March 1877 aged 55 years.
This memorial is erected by his brother officers
as a mark of their affectionate esteem.

Further Information
[From the Edinburgh Gazette]
"Lieutenant-Colonel George Stephen Digby, C.B., Royal Marine Artillery, having completed the qualifying service with the rank of Lieutenant-Colonel, to be Colonel, under the Order in Council of the 13th November 1858. Dated 23d March 1868."
Assuming that this memorial was raised soon after Digby's death in 1877 then it must have originally stood elsewhere as St. Andrew's was not opened until 1906. The obvious candidate was the Crinoline Church.