Holmes, Arthur (1890-1965) (World of Earth Science)
Arthur Holmes, geologist and geophysicist, was born in Gateshead, England. From a modest family background, in 1907 he gained a scholarship to study physics at the Royal College of Science (Imperial College), London, where he became interested in the newly emerging science of radioactivity and its application to dating minerals to solve geological problems.
Throughout his early life, Holmes struggled against financial hardship and frequently sought other work to support his research. Thus in 1911, he accepted a contract to prospect for minerals in Mozambique, where he conceived his vision of building a geological timescale based on radiometric dates. It was also there that he contracted a severe form of malaria.
In 1912, as a demonstrator at Imperial College, Holmes pioneered radiometric dating techniques and wrote the first of three editions of his celebrated booklet The Age of the Earth. In it, he estimated the earth to be 1,600 million years old, at that time an immense age and considered by many to be unacceptable. For the next 30 years, he pursued the topic, but it was not until the early 1940s that real progress was made on the geological timescale. By 1947, Holmes had pushed back the earth's age to 3,350 million years. However, it was not until 1956 that it was established at 4,550 million years.
Holmes married Maggie Howe (1885938) in 1914 and his first son was born in 1918. He escaped active service in the First World War due to recurring bouts of malaria but, by 1920, he was still only earning 200 pounds a year. Once again financial necessity compelled him to accept a post abroad, this time in Burma as chief geologist to the Yomah Oil Company (1920) Ltd. By 1922, however, the company had collapsed. Six weeks before leaving for home his young son caught dysentery and died. Eighteen months of unemployment followed Holmes' return to England, during which time he opened a Far Eastern craft shop in Newcastle-upon-Tyne.
In 1924, Holmes was offered the headship of a oneman geology department at Durham University. With his fortunes revived, and enhanced by the birth of his second son, this period saw an invigorated renewal of his research activities. An immediate supporter of the continental drift theory, originally proposed by Wegener in 1912, Holmes saw at once that it explained how identical fossils and rock formations occurred on either side of the Atlantic. However, the theory was then highly controversial, as no force was considered adequate to move continental slabs over the surface of the globe. It was Holmes' profound understanding of radioactivityhe amount of heat it generated and the enormous time it bestowed on geology for infinitely slow processeshat placed him in a unique position to formulate such a mechanism.
In 1927, Holmes gave a seminal paper which proposed that differential heating of the earth's interior, generated by the decay of radioactive elements, caused convection of the substratum (mantle). He calculated that convection could produce a force sufficient to drag continents apart, allowing the substratum to rise up and form new ocean floor. Evidence to corroborate this theory was not found until 1965, the year of Holmes' death, but by then his ideas were largely forgotten.
During the Second World War, Holmes was commissioned to write Principles of Physical Geology. Published in 1944, this famous book with its heretical chapter on continental drift, became an international best-seller that influenced generations of geologists. When Holmes retired in 1956, he set out to update the book, but with failing health it was a mammoth task, completed only months before he died.
Recognition of Holmes' outstanding contributions to geology came when he was elected Fellow of the Royal Society in 1942 and a year later appointed to the Regius chair in geology at Edinburgh University. In 1956, the Geological Societies of London and America awarded him their highest honors. In 1964, he was presented with the Vetlesen Prize, the geologist's equivalent of the Nobel Prize, for his "uniquely distinguished achievement in the sciences resulting in a clearer understanding of the earth, its history, and its relation to the universe."
Holmes was a deep thinker on the broad philosophical aspects of geology, with ideas far ahead of his time. Always of smart appearance, he was a gentleman of quiet charm and unfailing kindness. He had an exceptional talent for playing the piano, was fascinated by history, and loved poetry. In 1931, Holmes met Doris Reynolds (1899985), a geologist then working at University College, London. He engineered a lectureship for her in the Durham geology department, but they were unable to marry until 1939, nine months after the death of his first wife from cancer. Holmes died of bronchial pneumonia in 1965, leaving his beloved Doris to succeed him by 20 years.
See also Dating methods; Geologic time