[3] After practical experience on the Isle of Man, Wales and England, he spent a further year at the Royal School of Mines in London studying metallurgy.

[1] His report a "Deep-sinking Proposal on the Charters Towers Mineral Field", which included a scale model, was displayed at the Brisbane Exhibition, in August 1913.

[3] After becoming engaged to childhood friend, Nesta Drury in 1913, Marks returned to study in Ireland, pursuing a medical degree.

Marks graduated with his MD in 1919, but concerns about the lingering effect of rheumatic fever on his stamina, induced him to pursue ophthalmology.

Marks was in charge of the Wilson Ophthalmic Hostel for Trachomatous Children at Windsor and made four surveys of the eye disease, trachoma in western Queensland.

By 1953, the Wilson Hostel closed for lack of patients, due to his team's work in identifying and treating the disease.

[14] He played an important part in the establishment of the Heron Island Research Station, along with Dr Dorothy Hill.

[citation needed] Marks continued to serve in the military after his return to Australia, as a Captain and Army Ophthalmologist in the AAMC from 1923 until 1939.

[12] The Marks family held a strong view on the importance of science in the community, and belonged to many societies.

These included personal correspondence, scientific specimens, furnitures and the family's property at Samford, which was donated to QUT.