Royal Artillery Tracer Cards are now available of Ancestry.co.uk and they provide a summary of 'where' a soldier was at a particular time. Here I have collected together a few from the 9th Medium Regiment RA and will add to them in time. Not all men can be found but searches turned up a fair number.  You will see 'X Lists' referred to and they indicate when a man is absent from his unit for different reasons. Commonly 'X-List 2' is seen and this means evacuation on medical grounds beyond the Regimental Aid Post. This might not always be a wound but could be because of illness or accident. R.H.U. means Replacement Holding Unit and is a place personnel are held before returning to their unit or another unit. It is usual for any soldier in an R.H.U. to want to return to their own unit and friends as soon as possible!