Leslie Paterson Smail was the son of John Paterson Smail and his wife Mary (nee Potter).  He was born on 10 June 1895 at St. Helen's, 11 George Street, East Melbourne.  The family remained at this address for about three years but at the time of Leslie's enlistment on 29 February 1916 he was living with his family in Auburn.  His occupation was clerk.  He had had three years' experience with the Senior Cadets in the 48th Battalion.  At 5ft 4ins he was a small man, even by the standards of the day.  He had a fresh complexion, grey eyes and auburn hair.  He was appointed as a private to the 14th Australian Gneral Hospital at the Domain camp on 1 August 1916 having first had a month with the 19th Depot Battalion at Geelong followed by time with the Royal Australian Medical Corps at Royal Park.  For training in hospital duties the men were sent in batches to the wards and operating theatres of the Melbourne, Alfred St. Vincent's and Eye and Ear Hospitals. 

He embarked on 19 August 1916 on the Karoola.  The day before Major C Lowther Clarke had been taken on strength and appointed registrar of the 14th Australian General Hospital.  Major Clarke was the son of the then archbishop of Melbourne who lived at Bishopscourt, East Melbourne.  Major Clarke, himself, lived and practised in South Australia.  The ship arrived at Suez on 19 September where the unit was informed that it was to relieve the 3rd Australian General Hospital at Abbassia.  On arrival by train at Abbassia the men set about learning their duties, and the hospital opened on 23 September.  It could accommodate 1100 to 1200 patients and more if needed.  The hospital was described as 'a square of two-storied buildings with additional blocks outside and parallel to three of the sides of the square.  Wide verandahs on every building ...'

Smail spent four days in hsopital in October with an undiagnosed complaint, and on 22 January 1917 he was admitted to hospital and transferred to Montazah with lumbago and debility.  He was discharged on 9 February.

On 27 February 1917 he was transferred to 4th Light Horse Field Ambulance at Ferry Post, Ismalia (north east of Cairo).

On 15 June 1917 he was attached for duty with the 4th Light Horse Machine Gun Squadron at Tel-el-Fara, near Gaza.  Then returned to the Field Ambulance in October who were by then at El Mejdel, between Beirut and Damascus. 

On 14 December he was admitted to hospital at El Burj, Damascus and ten days later transferred to hospital at 14th Australian General Hospital at Abbassia, where he was diagnosed with para-typhoid. The medical report on his admission stated that 'about 4 or 5 weeks ago between Jaffa and Jerusalem he got diarrhoea and vomiting attacks.  The sight of food he says used to sicken him'.  He had lost a lot of weight and seemed weak.  His temperature hovered well over the 100 mark.  In March he was transferred to the Rest Camp at Port Said.  On 16 April at Moascar he joined the Australian Army Medical Corps Training Unit for a month and then he rejoined the Field Ambulance. 

On 1 June 1918 at Jordan Valley he was attached to the 4th Light Horse Regiment as Army Medical Corps Detail for duty with the Egyptian Expeditionary Forces.  He was made temporary coporal on 4 December.  

On 20 December he was detached to 11th Light Horse Regiment in Tripoli for similar duties.  More illness befell him.  He spent five days in hospital with pyrexia (fever) of unknown origin from 20 January 1919. He was promoted to corporal on 13 May 1919 and lance sergeant ten days later. Back in Abbassia he was admitted to hospital with Oriental Sore (a parasitic skin infection) on 9 June and rejoined his unit on 2 July.  He embarked for return to Australia with the 11th Light Horse Regiment on 20 July 1919.  He was discharged on 8 March 1920.

Little of his life is known after the war.  He was involved in local affairs and it was he, as honorary secretary, who called for tenders for repairs and renovations to the Camberwell Memorial Hall and provided specifications.  From at least 1950 he was working as a loss assessor.  He died on 11 September 1961 at Canterbury.