Checking 1911 census there are no Martins living on Williams Rd Ealing. Infact no one listed as living at No 10, so it may have been unoccuppied....
1891 Census shows Edward living at 10 Williams Road, Twyford Abbey Ealing, Brentford, Middlesex, working as a Carman - living with his wife Emma, sons Henry & Percy & daughter Jesse.
Also broading with them in 1891 is one Harriet Martin aged 23, born in the same place as Edward (Stambourne Essex) so might this be his sister/cousin, maybe the H Martin he was hoping to find living at no 10 Williams Rd.
Seems unlikely he would not have been on active service, given his age. The only circumstance might have been if he was an 'Old Contemptable' i.e and old soldier on reserve, then he may have re-enlisted and have been used in some capacity (like training) because of this previous experience. Otherwise, unless the postcard indicates military service specifically, he may have gone to France as a civilian to help in a non-combatant role, though that would been highly unusual....
