James Croll

Background

Croll was born on January 2, 1821, in the parish of Cargill, in Scotland. His father, David Croll, was a poor stonemason and crofter who at the age of thirty-seven married Janet Ellis.

Education

Croll was regarded as an unpromising boy, but a trifling circumstance aroused a passion for reading, and he made great progress in self-education. He was too poor to afford the university education he craved.

Career

Croll became first a journeyman millwright, then a house joiner, until an injury forced him to give up manual work. Throughout a varied but universally unsuccessful business career, Croll studied theology and metaphysics, publishing in 1857 The Philosophy of Theism. Giving up business in 1858, he wrote for a Glasgow temperance weekly before he found a post as caretaker of Anderson’s College and Museum in 1859. Leaving the work to his crippled younger brother David, whom he supported, Croll began to publish papers in chemistry and physics.

A paper in Philosophical Magazine (1864), in which he suggested that a change in the eccentricity of the earth’s orbit had been responsible for the drastic changes in climate associated with glaciation, brought Croll to the notice of the leaders of British science, with some of whom (like Tyndall and Carey Foster) he began a vigorous correspondence. This led to the post of resident geologist in the newly opened Edinburgh office of the Geological Survey, Where Croll remained from 1867 until his retirement in 1880. Here he continued his speculations about the causes of climatic change, publishing papers later brought together in Climate and Time (1875). Two more books on related topics, Discussions on Climate and Cosmology (1885) and Stellar Evolution and Its Relations to Geological Time (1889), appeared after he retired. The latter represents a shift of interest from the physical causes of climatic change to evolution. His final work, The Philosophical Basis of Evolution (1890), appeared just before he died.

Although Croll made some modest contributions to the study of glaciation in Scotland, his chief importance was as a controversialist. In his three scientific books and many papers he never let his lack of training in mathematics and physics keep him from propounding the broadest climatological and cosmological theories and defending them against the mathematically adept, such as George Darwin. A clear and logical thinker whose prodigious reading kept him abreast of the latest observations, Croll had a purely verbal grasp of major scientific issues that drew the admiration of Lord Kelvin, among others. The most important of the many scientific controversies in which he engaged was that on the cause of ocean currents, in which he backed wind stress against the thermohaline, or density, theory of W. B. Carpenter. This argument generated more heat than light, since neither protagonist had the methods or the data to resolve it. Croll’s contributions to science are confined to his own time: he stimulated others to develop both better evidence and more quantitative theories, and as a convinced Christian he helped make acceptable the geological ideas that followed from the theory of organic evolution.

Achievements

• Croll is best known as the scientist, who developed an astronomical theory of climate change 60 years before Milankovitch published a very similar theory. His work was widely discussed, but by the end of the 19th century, his theory was generally discredited.

Works

More photos

• book

  • Climate and Time in Their Geological Relations: A Theory of Secular Changes of the Earth's Climate 1875
  • Stellar Evolution, and Its Relation to Geological Time 1889
  • The Philosophy of Theism 1857

Membership

• Royal Society of London , United Kingdom

  1876

Personality

Croll claimed to have suffered all his life from ill health due to heart disease and strokes; but only the mild stroke in 1880 that led to his retirement and the heart disease that began in 1886 and led to his death seem to have been organic.

Connections

In 1848, Croll married Isabella Macdonald.

Father:

David Croll

Mother:

Janet Geddes

Spouse:

Isabella Macdonald

References

• Autobiographical Sketch of James Croll With Memoir of His Life and Work
  1896
• Dictionary of Scientific Biography Volume 3
  1971