My Grandfather is the tallest boy on back row.
He was born in 1895, so I'm guessing he was about 13 or 14 in the photo.
!n 1912 him and his younger brother went out to work in the copper mines in Michigan, returning to Cornwall in the 1920's with his American wife and 3 children.
He took over a farm and became quite successful as a cattle and pig dealer.