Another brother, George, was an antiquarian, founder of a local liberal newspaper and a prominent writer on economic and social matters.
He studied at the Aberdeen Grammar School, where he was nicknamed "Tertius" to distinguish him from other "King" namesakes, a name that stuck.
At the age of eighteen King decided to pursue a medical education and entered the University of Aberdeen in 1861, where he was influenced by his teachers George Dickie, Alexander Harvey and John Struthers.
in 1865 and joined the Indian Medical Service on 2 October, carrying with him an ipecacuanha plant from Hooker.
In 1869, the Superintendent of the Royal Botanic Garden, Calcutta, Thomas Anderson, fell ill and left for Europe, and in 1871, the Secretary of State for India selected King as a successor.
While on an official visit to the Nilgiris in July 1872, he developed symptoms of pulmonary phthisis (tuberculosis), and was treated in Coonoor, then moved to Europe.
King restructured the Calcutta Botanical Gardens, raising the level of the ground, creating ponds and laying out footpaths and conservatories.
King also altered the garden design from one segregated linearly on the basis of taxonomy to one based on regions, with combinations of species showing the natural plant associations.
Returning to India, King worked on a system for the distribution of the anti-malarial quinine through the postal department.
[1] Village post offices in Bengal were able to sell small packets for a pice, the lowest-denomination coin.
[5] King also wrote a series of articles Materials for a Flora of the Malayan Peninsula in the Journal of the Asiatic Society of Bengal.
In the following years King lost an eye due to a ruptured blood vessel, and increasing fell ill.
He reflected on the history of botany in India at the 69th meeting of the British Association for the Advancement of Science in 1899.
[1] He is buried in the cemetery in San Remo, and memorialised on the grave of his wife at St Machar's Cathedral in Old Aberdeen.
[8] As a landscape gardener, he was recognised by the Royal Horticultural Society and awarded the Victoria Medal of Honour in 1901.
For his work on making quinine and distributing it inexpensively he was made an honorary member of the Pharmaceutical Society and given a ring of honour by Czar Alexander III.