He was a pioneer of first aid, which in 1875 was unknown: even the police had no knowledge of basic techniques such as how to stop serious bleeding and applying splints.
Cantlie was born in Banffshire and took his first degree at Aberdeen University, carrying out his clinical training at Charing Cross Hospital, London.
One of his first pupils at the college was the future Chinese leader Dr. Sun Yat-sen. Cantlie's work in Hong Kong included investigations into leprosy and into various tropical diseases; in 1894 he encountered an outbreak of plague.
In 1896, poor health – related to his unstinting work as a researcher and practicing physician – forced Cantlie to return to London.
[4] During the early years of the twentieth century, and particularly during the First World War (1914–1919), Cantlie's work centred on the provision and training of ambulance services.