John H Williams

(Investigator 116, 2007 September)

While researching Greg Neyman's latest (#113) about Dr Dennis Swift and rock art depicting dinosaurs –  "Messages on Stone" – I came across a name that I'd omitted in my The Universe and The Earth (#107).

Arthur Holmes (1890-1965) was an outstanding British scientist whose fine 1944 text, The Principles of Physical Geology, was much used by me when a student in 1960-62.

My teacher, Arthur Harris MA, a double First at Cambridge, was a contemporary of Holmes, and a great fan. I'm shocked to realise that I'd not mentioned his work, despite being an admirer of his book, as I had no idea of his leading contributions to geochronology and to continental drift!

Holmes was probably the strongest supporter of Alfred Wegener's (1880-1930) ideas on continental drift, despite it receiving scepticism from the geological establishment. The circumstantial evidence was comprehensive, but no one had any idea about the mechanism that enabled continents to "plough through" oceans.

One American academic had weighed in with: "This theory is footloose…considerable liberty is taken with our globe…less bound  by restrictions or tied down by awkward, ugly facts than most of its rival theories." As Holmes said, "I have never succeeded in freeing myself of the nagging prejudice against continental drift." (1953)

Wegener's ideas would have remained virtually unnoticed without Holmes' work: in 1929 he (AH) theorised that it was "thermal convection in the mantle acting like a conveyor belt which moved continents around." This insight, an inspired one, was well ahead of current thinking!

About fifteen years later, sonic depth recording began making crude pictures of the sea floor, followed by the invention of the nuclear resonance magnetometer, allowing detailed mapping. In 1963 further oceanographical research led to the theory of sea floor spreading, part of what became known as plate tectonics, thus finally validating Wegener and Holmes.

Holmes was an outstanding scientist. While still an undergraduate at the Royal College of Science (later Imperial College), he was one of the first to set up radiometric dating experiments based on the breakdown of uranium to lead. In 1911, aged 21, he dated a Norwegian rock of Devonian age at 370 million years old, and two years later published The Age of the Earth, and estimated it at 1.6 billion years.

The rocky dating game generated a lot of heat in the first years of the twentieth century, with the iconic Lord Kelvin fiercely defending his 20-million-year old Earth until his death in 1907. There were many ‘teething problems' of technique, along with discoveries about nuclear isotopes. The leading physicists, such as Rutherford and Holmes' supervisor, Strutt, lost interest and focus, while Holmes was the "ingenious geoscientist" to persist.

Despite the geological die-hards, who resented the intrusion of physicists, Holmes pushed to have radiometric dating accepted in Britain as credible and reliable (1921), and was a prime mover for the American scientific establishment's ‘stamp of approval' in 1926.  

He was likely influenced by Rutherford's and Boltwood's work in 1905-1907, and his dating is similar to their 1907 estimate of 1.64 billion. Edwin Hubble thought it was 2 billion in the early 1920s, but Holmes and others realised that it was much older still. In 1927 he estimated its minimum age at 3.0 billion. In 1944 he estimated its age at 4.5 billion +/- 100my (latest age is 4.567 bn).

Contrast the work of Arthur Holmes with that of Dr Dennis Swift, a self-described "archaeologist, adventurer and pastor". One website states he has a Ph.D; another says he has a BA, MA, M Div and Th.D. His doctorate is in theology! He's the Pastor of Beaverton Nazarene Church, Oregon, and a young earth creationist purveying the non-sense of humans co-existing with dinosaurs, as noted by Greg Neyman.

Swift constantly reinforces Young Earth Creationism by providing scores of photographs of ancient Peruvian figurines which appear vaguely dinosaurian. The many photographs of these 'recently-seen' dinos is reminiscent of the plethora of purported UFOs shots, leaving one, ironically, even more convinced of their non-existence!

Arthur Holmes, Dennis Swift and Ken Ham: who of these three is most likely to be a disinterested, objective observer of our Earth's evolution?


Arthur Holmes, The Age of the Earth (Harper, 1913-1937)
G B Darymple, The Age of the Earth (Stanford Uni Press, 1993)
Cherry Lewis, The Dating Game: One man's Search For The Age of the Earth (Cambridge Uni Press, 2000).