Along with his brother Joseph G. Medlicott, he was able to determine the separation of the Cambrian Vindhyan region from the Gondwana. He later worked in various parts of the country such as South Rewa, Bihar, Assam, Khasi Hills, Rajputana, Kashmir, the Satpura ranges and the Garo Hills. On 1 April 1876 he succeeded Dr Oldham to head the Department of Geology and was posted in Calcutta. The position was changed from Superintendent to Director in 1885. Medlicott began to isolate himself from social life and began to live an ascetic life, walking barefoot and editing papers. He wrote "Manual of the Geology of India" with William Thomas Blanford in 1879 and edited works in the "Paleontologica Indica". His writing style was considered intemperate by his contemporaries but he began a policy to allow his subordinates free expression in print, a move that caused resentment among the staff. He was hostile to the promotion of native Indian geologists. He retired in April 1887 and lived at Clifton Bristol where he continued to research his interests in philosophy and theology. He died on 6 April 1905, leaving behind his wife, two sons and two daughters. He is credited with having suggested the name Gondwana. He used the term to describe stratigraphy of a mostly Permian formation in India. The geologist Edward Suess noted the widespread "Glossopteris" fossil flora and called all the regions "Gondwana-Land" and included India, Madagascar and Africa but not Australia.