I've had a quick look at your man's documents and - as far as I can decipher them - there is the following information:
Reuben J Blatchford [113441] of 105 Pembroke Street, Devonport aged 29 years and six months [on 19th October 1915] by trade a shoeing smith, a single man, attested on 19th October 1915 at Plymouth and was certified fit to serve on 1st March 1916 at Exeter.[not totally sure of that date]
He was born at Collingham[?] in Cornwall
Height 5 feet 5 ½ inches
Weight 138 lbs
Chest 40 inches when fully expanded – 3 inches of expansion
Next of kin: John and Elizabeth Blatchford – parents
His medical showed defective sight but he was passed fit for service in the field.
Statement of Services
Service counted from 19th October 1915
Passed at Hilsea on 20th October 1915
Posted initially to No. 3 Depot RFA
Posted to 13th reserve Battalion on 22nd October 1915
Posted to [?] as driver on 16th March 1916
Can’t read the next entry
Embarked at Southampton on 2nd June 1916
Disembarked at Le Harve on 3rd June 1916
[Next part v. difficult to read]
Seems to have been admitted to hospital in France sometime in 1916 and then what looks like “invalided to England” in January 1917
Elsewhere recorded as being in hospital with Trench feet between 4th January 1917 and 28th February 1918
He was then posted as a driver to 5c Reserve Brigade on what looks like 3rd May 1917
Posted back to France on 20th June 1917
I can’t read which unit or brigade he was posted to
He was in hospital “sick” on 29th April 1918 [still in France – a field hospital – diagnosed: “NYD ? TB”]
On 18th July 1918 diagnosed with “acute bronchitis”
He was then sent back to England – Posted to 6B Reserve Brigade Charlton Park SE London on 4th October 1918 and then transferred to High Wycombe
On 7th August 1918 he was issued with glasses at RACD Rippon, so he was there before High Wycombe and after Charlton Park.
He was a driver in the 11th Battery
There's probably more that can be pulled out - but it would take a lot more time and a bit of digging and cross-checking. As is usual with these "burnt documents" there are lots of entries that are very difficult to read.
Anyway - at least it's a start,
jds1949