Nicolas-Louis De La Caille - Astronomer And Geodesist
Ian S Glass
Oxford University Press
REVIEW: Lee Labuschagne
Our beautiful Southern night skies – especially in rural areas – do not only enthral local and foreign sky gazers.
With the Southern African Large Telescope (Salt) in operation at Sutherland, South Africa is today attracting the attention of many professional astronomers from around the globe – and will increasingly do so in terms of radio astronomy as construction work, first on the Meerkat radio telescope project and the Square Kilometre Array (SKA) near Carnarvon, progresses.
But international astronomers have for centuries had their eyes fixed to our skies, and Professor Ian Glass, himself a well-known professional astronomer, has written a fascinating biography about one of the earlier pioneers who had a big impact on the science and who did much of his work at the Cape.
Frenchman Nicholas-Louis De La Caille is fairly well known as the 18th century observer who gave many of the Southern constellations their names, but among others he also made the first telescopic sky survey.
Like many scientists of his time, his interests and skills went wider than one area of specialisation and La Caille also became renowned as a geodesist.
At the time the shape of our planet was not clearly defined yet, and La Caille mapped the Cape, among others making a controversial measurement of the Earth that seemed to prove it was pear-shaped.
Later it was shown that this was the result of the gravitational attraction of Table Mountain and the Piketberg slightly deflecting the bob at the end of the plumb lines he was using to make his measurements!
How this was proven forms part of the story in a book that shows clearly how people strive to overcome the practical challenges of gathering of scientific information, using the methods available at their time.
Professor Glass, who has published a number of other books with astronomy-historical themes, has written an excellent, and probably the most comprehensive, look at La Caille’s life and achievements yet.
It gives a fascinating insight into this 18th century scientist’s work under conditions that were quite daunting, and places it in a context that refers also to other scientists and scientific endeavours at the Cape and internationally at the time.
Like his Revolutionaries of the Cosmos: the Astrophysicists and Proxima: The Nearest Star, he makes what could have been a dry topic accessible, irrespective of interest level.
With many fascinating quotes from La Caille’s own notes and letters, and those of his colleagues and others, this becomes a biography that is entertaining and educational at the same time.
It’s recommended reading for anyone interested in the history of science locally – and especially for those interested in the history of the Cape, astronomy or the mapping of southern Africa.
The illustrations are excellent and help to make the material accessible, while the footnotes and appendices provide useful additional information about astronomical terms, currency and length conversions and a timeline. - Cape Times