Arthur St. John Adcock was born in Marylebone, London on 17th January 1864. He studied law and later became a Fleet Street journalistHe married Marion Louisa Taylor in Birkenhead, Wirral in 1887 and the couple had two daughters. In 1901, the family lived in Hampstead and in 1911 in Hertfordshire and in 1911 they lived in Rickmansworth, Hertfordshire.
Adcock died on 9th June 1930.Adcock’s First World War writing includes:
In the Firing Line (1914) editor, a collection of letters written from the Front in the early days of the war before censorship - available as a down-load on Archive https://archive.org/stream/infiringlinestor00adcoiala#page/n7/mode/2upSeeing It Through 
His WW1 poetry collections were:
City Songs (Selwyn & Bloom, 1926)
Exit Homo (Selwyn & Bloom, 1921)
Songs of the World War (Palmer & Hayward, 1916)
Tod MacMammon sees his soul, and other satires for the new democracy (poems) (Swarthmore, P. 1921)
and his poems were included in three WW1 Anthologies.
Adcock also published:
Australasia Triumphant! With the Australians and New Zealanders in the Great War on Land And Sea (1916)
The Odd Volume (1917) editor, stories
For Remembrance. Soldier Poets who have Fallen in the War. With nineteen portraits (1918)
The ANZAC Pilgrim's Progress: Ballads of Australia's Army (1918) Lance-Corporal Cobber, editor (Simpkin, Marshall, 1918
The Divine Tragedy (1922)
Sources: https://en.wikipedia.org/wiki/Arthur_St._John_Adcock and Catherine W. Reilly ‘English Poetry of the First World War A Bibliography’ (St. Martin’s Press, New York, 1978)