Alexander Du Toit
Encyclopedia
Alexander Logie du Toit (icon ; 14 March 1878 – 25 February 1948) was a geologist
from South Africa, and an early supporter of Alfred Wegener
's theory of continental drift
.
Born in Newlands
, Cape Town
in 1878, du Toit was educated at the Diocesan College
in Rondebosch
and the University of the Cape of Good Hope
. Encouraged by his grandfather, Captain Alexander Logie, he graduated in 1899 in mining engineering
at the Royal Technical College
in Glasgow
. After a short period studying geology
at the Royal College of Science
in London, he returned to Glasgow to lecture in geology, mining and surveying at the University of Glasgow
and the Royal Technical College.
In 1903, du Toit was appointed as a geologist within the Geological Commission of the Cape of Good Hope, and he began to develop an extensive knowledge of the geology of southern Africa by mapping large portions of the Karoo
and its dolerite intrusions, publishing numerous papers on the subject. Subsequently he mapped the entire Karoo System through the complete stratigraphy from Dwyka tillite to the basalt
of the Drakensberg
. He worked at a furious rate but was known for his painstaking meticulousness. This is reflected in his book "Our Wandering Continents". It still bears reading for its creative and closely argued theses in the light of the geology of the day, and is soberingly consistent with modern principles of plate tectonics.
In 1920 du Toit joined the Union Irrigation Department as water geologist, and in 1927 became chief consulting geologist to De Beers Consolidated Mines, a position he held to his retirement in 1941.
In 1923, he received a grant
from the Carnegie Institution of Washington, and used this to travel to eastern South America to study the geology of Argentina
, Paraguay
and Brazil
. As is apparent from his remarks in "Our Wandering Continents", he had not requested support for the expedition on a whim, but specifically to test his predictions of correspondences between the geology of the two continents. In the event he was able to demonstrate and follow the predicted continuation of specific features already documented in Southern Africa, into the continent of South America. Although that might perhaps seem less impressive to the layman, to the geologist this evidence was far more crushing than any arguable ex post facto matching of continental shelves.
In the light of his research du Toit published a review of the stratigraphic
and radioisotope
evidence from these regions that supported Alfred Wegener's ideas, A Geological Comparison of South America with South Africa (1927). His best-known publication, Our Wandering Continents (1937), expanded and improved this work, and, departing somewhat from Wegener, proposed two original supercontinent
s separated by the Tethys Ocean
, a northern
/equator
ial Laurasia
and a southern
/polar
Gondwanaland.
In 1933, du Toit was awarded the Murchison Medal
by the Geological Society of London
, and in 1943 became a Fellow of the Royal Society
. In 1949, the year after du Toit's death, the Geological Society of South Africa
inaugurated a biennial lecture series in his honour that continues to the present day. In 1973, a 75 km crater
on Mars
(71.8°S, 49.7°W) was named "Du Toit" in recognition of his work.
Geologist
A geologist is a scientist who studies the solid and liquid matter that constitutes the Earth as well as the processes and history that has shaped it. Geologists usually engage in studying geology. Geologists, studying more of an applied science than a theoretical one, must approach Geology using...
from South Africa, and an early supporter of Alfred Wegener
Alfred Wegener
Alfred Lothar Wegener was a German scientist, geophysicist, and meteorologist.He is most notable for his theory of continental drift , proposed in 1912, which hypothesized that the continents were slowly drifting around the Earth...
's theory of continental drift
Continental drift
Continental drift is the movement of the Earth's continents relative to each other. The hypothesis that continents 'drift' was first put forward by Abraham Ortelius in 1596 and was fully developed by Alfred Wegener in 1912...
.
Born in Newlands
Newlands, Cape Town
Newlands is an upmarket suburb of Cape Town, South Africa.It is located at the foot of Table Mountain in the Southern Suburbs of Cape Town, and is the wettest suburb in South Africa due to its high winter rainfall...
, Cape Town
Cape Town
Cape Town is the second-most populous city in South Africa, and the provincial capital and primate city of the Western Cape. As the seat of the National Parliament, it is also the legislative capital of the country. It forms part of the City of Cape Town metropolitan municipality...
in 1878, du Toit was educated at the Diocesan College
Diocesan College
The Diocesan College, or Bishops as it is more commonly known, is an independent, all-boys school situated in the suburb of Rondebosch in Cape Town, South Africa...
in Rondebosch
Rondebosch
Rondebosch is one of the Southern Suburbs of Cape Town, South Africa. It is primarily a residential suburb, with a medium-size shopping area, a small business district as well as the main campus of the University of Cape Town.-History:...
and the University of the Cape of Good Hope
University of the Cape of Good Hope
The University of the Cape of Good Hope, renamed the University of South Africa in 1916, was created by Act 16 of 1873 of the Cape of Good Hope Parliament. Modelled on the University of London, it offered examinations but not tuition, and had the power to confer degrees upon successful examination...
. Encouraged by his grandfather, Captain Alexander Logie, he graduated in 1899 in mining engineering
Mining engineering
Mining engineering is an engineering discipline that involves the practice, the theory, the science, the technology, and application of extracting and processing minerals from a naturally occurring environment. Mining engineering also includes processing minerals for additional value.Mineral...
at the Royal Technical College
Royal College of Science and Technology
The Royal College of Science and Technology, situated at 138 George Street in Glasgow, Scotland was the principal predecessor institution of the University of Strathclyde, and now serves as one of the main educational buildings of the campus.-History:...
in Glasgow
Glasgow
Glasgow is the largest city in Scotland and third most populous in the United Kingdom. The city is situated on the River Clyde in the country's west central lowlands...
. After a short period studying geology
Geology
Geology is the science comprising the study of solid Earth, the rocks of which it is composed, and the processes by which it evolves. Geology gives insight into the history of the Earth, as it provides the primary evidence for plate tectonics, the evolutionary history of life, and past climates...
at the Royal College of Science
Royal College of Science
The Royal College of Science was a higher education institution located in South Kensington; it was a constituent college of Imperial College London from 1907 until it was wholly absorbed by Imperial in 2002. Alumni include H. G. Wells and Brian May and are distinguishable by the letters ARCS ...
in London, he returned to Glasgow to lecture in geology, mining and surveying at the University of Glasgow
University of Glasgow
The University of Glasgow is the fourth-oldest university in the English-speaking world and one of Scotland's four ancient universities. Located in Glasgow, the university was founded in 1451 and is presently one of seventeen British higher education institutions ranked amongst the top 100 of the...
and the Royal Technical College.
In 1903, du Toit was appointed as a geologist within the Geological Commission of the Cape of Good Hope, and he began to develop an extensive knowledge of the geology of southern Africa by mapping large portions of the Karoo
Karoo
The Karoo is a semi-desert region of South Africa. It has two main sub-regions - the Great Karoo in the north and the Little Karoo in the south. The 'High' Karoo is one of the distinct physiographic provinces of the larger South African Platform division.-Great Karoo:The Great Karoo has an area of...
and its dolerite intrusions, publishing numerous papers on the subject. Subsequently he mapped the entire Karoo System through the complete stratigraphy from Dwyka tillite to the basalt
Basalt
Basalt is a common extrusive volcanic rock. It is usually grey to black and fine-grained due to rapid cooling of lava at the surface of a planet. It may be porphyritic containing larger crystals in a fine matrix, or vesicular, or frothy scoria. Unweathered basalt is black or grey...
of the Drakensberg
Drakensberg
The Drakensberg is the highest mountain range in Southern Africa, rising to in height. In Zulu, it is referred to as uKhahlamba , and in Sesotho as Maluti...
. He worked at a furious rate but was known for his painstaking meticulousness. This is reflected in his book "Our Wandering Continents". It still bears reading for its creative and closely argued theses in the light of the geology of the day, and is soberingly consistent with modern principles of plate tectonics.
In 1920 du Toit joined the Union Irrigation Department as water geologist, and in 1927 became chief consulting geologist to De Beers Consolidated Mines, a position he held to his retirement in 1941.
In 1923, he received a grant
Research funding
Research funding is a term generally covering any funding for scientific research, in the areas of both "hard" science and technology and social science. The term often connotes funding obtained through a competitive process, in which potential research projects are evaluated and only the most...
from the Carnegie Institution of Washington, and used this to travel to eastern South America to study the geology of Argentina
Argentina
Argentina , officially the Argentine Republic , is the second largest country in South America by land area, after Brazil. It is constituted as a federation of 23 provinces and an autonomous city, Buenos Aires...
, Paraguay
Paraguay
Paraguay , officially the Republic of Paraguay , is a landlocked country in South America. It is bordered by Argentina to the south and southwest, Brazil to the east and northeast, and Bolivia to the northwest. Paraguay lies on both banks of the Paraguay River, which runs through the center of the...
and Brazil
Brazil
Brazil , officially the Federative Republic of Brazil , is the largest country in South America. It is the world's fifth largest country, both by geographical area and by population with over 192 million people...
. As is apparent from his remarks in "Our Wandering Continents", he had not requested support for the expedition on a whim, but specifically to test his predictions of correspondences between the geology of the two continents. In the event he was able to demonstrate and follow the predicted continuation of specific features already documented in Southern Africa, into the continent of South America. Although that might perhaps seem less impressive to the layman, to the geologist this evidence was far more crushing than any arguable ex post facto matching of continental shelves.
In the light of his research du Toit published a review of the stratigraphic
Stratigraphy
Stratigraphy, a branch of geology, studies rock layers and layering . It is primarily used in the study of sedimentary and layered volcanic rocks....
and radioisotope
Radionuclide
A radionuclide is an atom with an unstable nucleus, which is a nucleus characterized by excess energy available to be imparted either to a newly created radiation particle within the nucleus or to an atomic electron. The radionuclide, in this process, undergoes radioactive decay, and emits gamma...
evidence from these regions that supported Alfred Wegener's ideas, A Geological Comparison of South America with South Africa (1927). His best-known publication, Our Wandering Continents (1937), expanded and improved this work, and, departing somewhat from Wegener, proposed two original supercontinent
Supercontinent
In geology, a supercontinent is a landmass comprising more than one continental core, or craton. The assembly of cratons and accreted terranes that form Eurasia qualifies as a supercontinent today.-History:...
s separated by the Tethys Ocean
Tethys Ocean
The Tethys Ocean was an ocean that existed between the continents of Gondwana and Laurasia during the Mesozoic era before the opening of the Indian Ocean.-Modern theory:...
, a northern
Northern Hemisphere
The Northern Hemisphere is the half of a planet that is north of its equator—the word hemisphere literally means “half sphere”. It is also that half of the celestial sphere north of the celestial equator...
/equator
Equator
An equator is the intersection of a sphere's surface with the plane perpendicular to the sphere's axis of rotation and containing the sphere's center of mass....
ial Laurasia
Laurasia
In paleogeography, Laurasia was the northernmost of two supercontinents that formed part of the Pangaea supercontinent from approximately...
and a southern
Southern Hemisphere
The Southern Hemisphere is the part of Earth that lies south of the equator. The word hemisphere literally means 'half ball' or "half sphere"...
/polar
South Pole
The South Pole, also known as the Geographic South Pole or Terrestrial South Pole, is one of the two points where the Earth's axis of rotation intersects its surface. It is the southernmost point on the surface of the Earth and lies on the opposite side of the Earth from the North Pole...
Gondwanaland.
In 1933, du Toit was awarded the Murchison Medal
Murchison Medal
An award established by Roderick Murchison, who died in 1871. One of the closing public acts of Murchison’s life was the founding of a chair of geology and mineralogy in the University of Edinburgh. Under his will there was established the Murchison Medal and geological fund to be awarded annually...
by the Geological Society of London
Geological Society of London
The Geological Society of London is a learned society based in the United Kingdom with the aim of "investigating the mineral structure of the Earth"...
, and in 1943 became a Fellow of the Royal Society
Royal Society
The Royal Society of London for Improving Natural Knowledge, known simply as the Royal Society, is a learned society for science, and is possibly the oldest such society in existence. Founded in November 1660, it was granted a Royal Charter by King Charles II as the "Royal Society of London"...
. In 1949, the year after du Toit's death, the Geological Society of South Africa
Geological Society of South Africa
The Geological Society of South Africa is a learned society for geological science that was founded in 1895, making it one of the oldest such societies in Africa...
inaugurated a biennial lecture series in his honour that continues to the present day. In 1973, a 75 km crater
Impact crater
In the broadest sense, the term impact crater can be applied to any depression, natural or manmade, resulting from the high velocity impact of a projectile with a larger body...
on Mars
Mars
Mars is the fourth planet from the Sun in the Solar System. The planet is named after the Roman god of war, Mars. It is often described as the "Red Planet", as the iron oxide prevalent on its surface gives it a reddish appearance...
(71.8°S, 49.7°W) was named "Du Toit" in recognition of his work.
Significant publications
- du Toit, A.L. (1926) The Geology of South Africa, Oliver & Boyd, London, UK
- du Toit, A.L. and Reed, F.R.C. (1927) A Geological Comparison of South America with South Africa, Carnegie Institution of Washington, Washington, USA
- du Toit, A.L. (1937) Our Wandering Continents; An Hypothesis of Continental Drifting, Oliver & Boyd, London, UK
External links
- Biography (Charles H. Smith, Western Kentucky UniversityWestern Kentucky UniversityWestern Kentucky University is a public university in Bowling Green, Kentucky, USA. It was formally founded by the Commonwealth of Kentucky in 1906, though its roots reach back a quarter-century earlier....
) - Obituary notice (Obituary Notices of Fellows of the Royal Society 6, 385-395, Nov. 1949)
- Review of biography of du Toit (Geographical Review 41, 513-514)
- Alexander du Toit's map of two ancient supercontinents (more details here; Hartebeesthoek Radio Astronomy ObservatoryHartebeesthoek Radio Astronomy ObservatoryThe Hartebeesthoek Radio Astronomy Observatory is a radio astronomy observatory located in a natural bowl of hills at Hartebeesthoek just south of the Magaliesberg mountain range, Gauteng, South Africa, about 50 km west of Johannesburg...
) - Alexander du Toit papers and letters archive (University of Cape TownUniversity of Cape TownThe University of Cape Town is a public research university located in Cape Town in the Western Cape province of South Africa. UCT was founded in 1829 as the South African College, and is the oldest university in South Africa and the second oldest extant university in Africa.-History:The roots of...
)
