Morpeth Herald 01/06/1917 carries a brief obituary:
ROLL OF HONOUR
HORN.- Killed in action, May 7th [sic], aged 20, Pte. William James Horn, 1598, D.L.I., eldest son of Mr and Mrs Horn, of 8 Oswald Terrace, Amble.
William James Horn is remembered at Amble on A13.01, A13.03 and A13.07
He is also remembered in The DLI Book of Remembrance page 121