Dr. Earle was born in Acton, Middlesex, on 10 August 1882, was educated at the City of London School and subsequently Downing College, Cambridge, where he was a foundation scholar and to the Westminster Hospital. He gained a first class in the Natural Science Tripos. He took the Cambridge Bachelor of Arts degree in 1905 and the Master of Arts, Bachelor of Medicine degrees of that University in 1913. He later wrote "... I can well remember taking a course on Physiological Chemistry given by Professor Hopkins, of Cambridge, in which he referred to Biochemistry as the Cinderella of Physiology. I do not remember what the ugly sisters stood for, but it may have been Histology and Electro-Physiology, because it was at this time that the study of the muscle-nerve preparation of the frog became available for students' class work..."
He was a Demonstrator in Physiology from 1904 to 1915 and Joint Lecturer in Biology at the Middlesex Hospital in London from 1909 to 1915. He was also Temporary Assistant Physician at the Royal Waterloo Hospital between 1914 and 1915.
He moved to Hong Kong in 1915 where he spent 18 years until 1928. He was the Professor of Physiology and Biology at the University of Hong Kong and became the founding Chairman of the Physiology in 1918. He was Dean of the Faculty of Medicine from 1916 to 1920, 1923, and 1925.
In 1916 election, he ran for the elected seat on the Sanitary Board but lost to Dr. F. M. G. Ozorio. In the same year, he acted as Honorary Visiting Physician to the Government Civil Hospital during the absence of George Ernest Aubrey in 1916. He was registered to practice in 1917 and acted as member of the Medical Board in 1918 vice Kenelm Hutchson Digby's absence and again in 1923.
In 1928, he was appointed General Adviser to the Lester Trust and Director of the Henry Lester Institute of Medical Research and Preventive Medicine in Shanghai. Dr. Earle also involved in the development of Physiological Sciences in China. He was the Director of the Chinese Association for Physiological Sciences and co-founded the Chinese Journal of Physiology.
Dr. Earle was a Fellow of the Royal Society of Medicine and Fellow of the Royal Society of Tropical Medicine and Hygiene. He carried out researches in metabolism and many of his papers including one on the Basal Metabolism of Chinese and Westerners were published in scientific journals.
Dr. Earle was honoured with the Doctor of Laws honorary degree with Governor Sir Wilfred Thomas Southorn at the 27th Congregation of the University of Hong Kong on 6 January 1936.
Dr. Earle married Audrey Mary Harrison and had four children, Barbara Mary, John Esmond Gastineau, Audrey Monica and Catherine Rosemary.
During the Second World War, he was interned by the Imperial Japanese Army at the Lunghwa Civilian Assembly Centre in Shanghai from 1943 to 1945. He died at sea, on board a ship where his son Esmond was the ship's doctor, on 5 June 1946 after a stroke on the journey returning to the United Kingdom in 1946 at the age of 64.Basal Metabolism with Special Reference to Chinese Students (1923)
An Imperial Policy in Education (1926)
Report on the Lester Trust, Shanghai (1927)
Basal Metabolism of Chinese and Westerners (1928)