Henry A Parsons, Worcestershire Regiment 38642

I'm trying to find infrormation on my G G Grandfather Henry A Parsons and have unfortunately hit a brick wall. Information I do have is that he was in the Dorsetshire Regiment (8748) and then the Worchestershire regiment (38642). What I cannot find however is his Battalion number, date of enlistment (I suspect it was probably pre WW1) and discharge date. The latest date I have for him being in the Worchester regiment is 1917.
Any information that can be provided would be very gratefully appreciated
Many Thanks
Any information that can be provided would be very gratefully appreciated
Many Thanks