I have just realised that we haven’t introduced Jack, Harry’s brother, the recipient of around half the letters.
John Ernest (Jack) Lamin was born in 1870 to Henry Lamin.. He was considerably older than Harry.
By the 1901 census he was an elementary schoolmaster living in Oxford. Harry is recorded as staying with him. Oxford is mentioned in quite a few of the letters so Harry must have stayed there for a while.
In 1917 John was a clergyman living in Newland, Hull Yorkshire.
He eventually became a canon (an honourary title in the Anglican Church, given to senior, well respected members of the clergy) attached to the Cathedral at York.
Willie knew John quite well and always referred to him in a respectful manner. I haven't yet established details of the latter part of his life.