1882 Jul 13. Born Great Baddow, Chelmsford, Essex
1891 census at Moulsham St , Chelmsford
1896 Apr 25 . Enlisted in Royal Marines. Thomas William Mumford, born: Great Baddow, Chelmsford, Essex; Age at attestation: 14 (he was only 13 in fact) ; Attested: Chatham; Joined in: 1896; Discharge reason: Invalided; Discharge year: 1897.
1898 May 26. Enlists in DCLI
1898 Dec 15 Appointed L/Cpl
1901 census his parents are at the address on the enlistment papers at 14 New Rd
1906 May 25 Transferred to Army Reserves
1910 May 25 Discharged as a Sergeant
1910 Oct 38 Re-enlisted as a sergeant for 4 years
He then seems to disappear from records as "Thomas W Mumford" and when he joins ADRIC gives Royal Fusiliers as his regiment. The reason seems to be that he was commissioned as "Thomas Mumford"
1915 Sep 25. Commissioned 2nd Lt in Royal Fusiliers "Thomas Mumford"
1917 Oct 19. There is a T Mumford who is Attached to R FUS who has the following entry on the 19th Oct 1917: Temp. 2nd Lt. (attd.) T. Mumford to be temp. Lt. (attd.). 1 July 1917. Temp. Lt. (attd.) T. Mumford relinquishes his commission on account of ill health contracted on active service, and is granted the hon. rank of Lt. 24 Oct. 1917.
1918 Aug 1. RFC. The undermentioned 2nd Lts. to be temp. Lts. whilst empld. as Lts.: — (Hon. Lt.) T. Mumford
1918 Aug 8. RFC. Sec. Lieut. T. Mumford to be actg. Lieut, whilst employed as Lieut, from Aug. 8, 1918, to April 30
1919 Sep 9. Transferred to unemployed list. 2nd Lt. (Hon. Lt.) T. Mumford
1920 Aug 6. Joined ARIC with service no 129. Posted to Depot Coy
1920 Nov 20 Promoted Section Leader
1921 Mar 12. Posted to P Coy
1921 Sep 9. Permitted to resign on compassionate grounds
I do not know if this is him