Despite his Canadian origin there is no reason to suppose that Ellis's military experience was very different from that of temporary medical officers recruited in the United Kingdom. His abrupt departure in 1918 was not unusual: RAMC diaries contain numerous entries along the lines, 'Lieutenant X departed for England on expiry of contract.' The diaries identify a source of medical support not mentioned by Whitehead; 1918 entries show American medical officers joining units of the British army. Nor does Whitehead refer to a remarkable inducement offered to doctors from overseas, the option of being accompanied by their wives. Ellis married May Johnstone just before leaving for France; she accompanied him to Britain and lived in London during the period of his service. May found the zeppelin raids unsettling, and this no doubt contributed to Ellis's decision to return to Canada in May 1918 after two years with the Welsh Division.
Ellis Carlton Arthur Reynolds (1893 - 1967), the youngest of four children of Arthur and Elizabeth Reynolds, was born in Darlington Township in the County of Durham, a few miles east of Toronto. He attended Trinity College Medical School, graduating with the degrees MD and CM in 1905, by which time the Trinity school had been incorporated into the Faculty of Medicine of the University of Toronto. The greater part of Ellis's medical career was spent in the villages of Erin and Hillsburg, in Wellington County, a few score miles northeast of Toronto. On retiring he and May moved to the Toronto suburb of East York; they are buried in Hampton Cemetery, not far from Solina, the village in which Ellis was born.
Although Ellis said little of his military service, the memory of his mentioning the Welsh Division was sufficient to reveal a good deal about it, thanks to the records punctiliously maintained by both medical and fighting units. His name appears some thirty times in the diaries kept by successive ADMS (Assistant Directors of Medical Services) of the Welsh Division and by the commanders of the Field Ambulances in which Ellis worked, the 130th (St John) FA and the 131st FA. The diaries of the 114th and 115th Infantry Brigades, to which the two Field Ambulances were attached, of their battalions and of the division itself provide further insights into his experiences. What these sources reveal about his military career is set out in the table that follows.
Ellis joined the Welsh Division in May 1916, some six weeks before the division was engaged in 'the big push', the Battle of the Somme, in which it was badly mauled in actions near Mametz. When he joined, the division was encamped near La Gorgue, on the south bank of the River Lys opposite Estaires, some five miles west of Armentières. A month later it was at Merville, also on the Lys, a town about five miles west of Estaires, and from other diary entries it can be deduced that the Welsh spent much of the War in that vicinity, making occasional forays to take part in the battles of the Somme, Messines and Passchendaele.
A month after the commencement of the Somme campaign Ellis was in hospital with 'pyrexia of uncertain origin'. A letter from C. S. Lewis (who suffered from it in 1918) published in 'The Times' on 16 Feb 1918 (and again on 16 Feb 2004) explains that PUO, as it was known, was even more commonly known as trench fever. Ellis recalled being gassed (the diaries mention several gas attacks), but this had no apparent long-term effect on his health.
While with the 131st Field Ambulance Ellis was, the diaries suggest, attached to the Field Ambulance itself rather than to one of the 115th Brigade's battalions. In the latter stages of his service he appears to have acted as movements officer, leading an advance party when the unit moved, following the brigade it served. This was a natural role for a boy brought up on a farm and more familiar with horses and horse-drawn transport than were the others of the medical staff. During the attack on Pilckem Ridge, Ellis had command of the brigades stretcher bearers; among the illustrations in 'Doctors in the Great War' is the well-known photograph showing bearers in that battle, up to their knees in mud.
While information on temporary medical staff must be gleaned from the War Diaries of the units to which they were attached, the careers of more senior, permanent RAMC officers are set out in publications such as the Army List, Who's Who and Who Was Who. From the historian's point of view Col Frederick James Morgan CMG CBE (1861 - 1931) was the ideal ADMS, his diary entries being helpfully comprehensive. Service in South Africa had netted Morgan a mention in despatches, the Queen's Medal with three clasps and the King's Medal with two clasps, and he was mentioned in despatches on four occasions while serving in Europe during the Great War. He left the Welsh Division to become DDMS of the Cavalry Corps. A successor, James Chambers Sproule, served also in the Second World War, acting as Deputy Director of Hygiene for Eastern Command with the rank of Temporary Brigadier.
Lt Col Robert Herbert Mills-Roberts FRCS (Edinburgh) CMG TD and later JP, who commanded the 131st Field Ambulance, had a particularly interesting career. As the senior Field Ambulance commander of the Welsh Division he often acted for the ADMS when the latter was on leave. A Welsh international footballer, Mills-Roberts kept goal for Preston North End in the season in which they lost no matches and conceded no goals in the final. (Not until 2004 was this unbeaten performance equalled by Arsenal FC.) Author of several medical papers, he was surgeon of the Dinorwic Hospital and Quarries before the War and Deputy Commissioner for Medical Services in North Wales and Shropshire afterwards. He had served with the Welsh Hospital in South Africa and later, from 1906 to 1915, was second-in-command of the 6th Royal Welsh Fusiliers. He then reverted to a medical role, commanding first the 131st FA and later the 41st Stationary Hospital. In having experience of both fighting and medical units, Mills-Roberts resembled Lt Col John McCrae RCAMC, author of the well-.known poem 'In Flanders Fields'.
Although Whitehead sets out widely held critical views of permanent RAMC staff, as lacking up-to-date medical knowledge and serving largely administrative roles during the War, those under whom Ellis worked appear to have had a wide range of experience in both military and civilian spheres, and were well able to train and advise the civilian doctors through whom front-line medical services were delivered.