If you’d like to find out more about 58 Bde, RFA, I would recommend the following:
Details of the brigade’s service overseas may be found in their War Diaries, available from The National Archives under references WO95/4298, WO95/1800(1-5) and WO95/1801(1-4).
Letters written by Robert Bragg during his service in A/58 are available from the Royal Institute’s website, under the heading “The Bragg Family in WW1: Selected Correspondence”
“Broken by Messines” by Dr Mark Wardlaw, tells through letters from A/58 soldier, Peter Hutchinson Wardlaw, the love affair between him and his future wife and how injuries he sustained in action blighted their futures.
“Medal Without Bar” by Richard Blaker, is a semi-autobiographical account of Blaker’s experiences as a subaltern in D/58 from July 1916 until July 1917.
Chris Baker’s website, “The Long Long Trail” is a very valuable resource giving details about all of the units in the British Army in the Great War and the Imperial War Museum’s project “Lives of the First World War“ provides usually very limited details of just about everyone who served in WW1.
Ian Jones’ blog on “A/58 Mobile Field Battery RFA” provides the details and history of the mechanisation of that battery for two months towards the end of the war.
And if you are interested in other topics associated with 58 Bde and those served with it, then you may also like to explore the following:
For more information on the Royal Army Medical Corps, “RAMC in the Great War” provides details on many of those who served in that corps.