Found an article in "The Scotsman" dated Saturday, 3rd May 1913, on The British Newspaper Archive website. A list of soldier's names and regiments including Sergeant R. Eglington, Military Provost Staff Corps. I can't access the full article but I think it's about courses/qualifications these men have passed.
Above Regiment/Corps matches information on Robert and Martha's Scottish Marriage Certificate. (Not easy to read in parts.) Transcription:
1913 Marriages in the District of Stirling in the County of Stirling.
On 8th October 1913 at Waverley Hotel, Murray Place, Stirling. After Banns According to the Forms of the Established Church of Scotland.
(Signed) Robert Eglington, Sergeant - Military Provost Staff Corps. (Bachelor) age 31yrs. Address: 36 Upper Bridge Street, Stirling. Parents: Emerson? Eglington. Joiner (Journeyman) and Sarah Matilda? Eglington ms Poole?. To:
(Signed) Martha Sanderson (Spinster) age 29yrs. Address: 27 Nelson Place, Stirling. Parents: William Norman? Sanderson. Railway Yardsman (deceased) and Catherine Sanderson ms McDougall.
(Signed) D.P. McLean? - Minister of Stirling (?). (Signed) Albert Barlan? - Witness. (Signed) Mary Macnaughton Sanderson - Witness. Registered: 11th October 1913 at Stirling. (Signed) Hugh Webster? - Assistant Registrar. (Counter signed by Registrar at bottom of page. Signature unreadable.) [Statutory Marriages 490/ 158] ScotlandsPeople.
Also this Birth Notice in the "Stirling Observer" dated 29th August, 1914. "EGLINGTON - At IS,? Married Quarters, Stirling, on 24th August, the wife of Sergeant R. Eglington, of a son."