Marie-Jeanne Amélie Harlay


Born: 1768 in Paris, France
Died: 1832 in Paris, France


Amélie Harlay was the illegitimate daughter of the astronomer Joseph-Jérôme Lefrançais de Lalande. She married Michel Jean Jérôme Lefrançais de Lalande (1776-1839), the younger cousin of Jérôme Lalande who referred to Michel and Amélie as his nephew and niece. Jérôme Lalande taught astronomy to them both and wrote the following description of Amélie in his work Bibliographie Astronomique (Paris, 1803):-

My niece aids her husband in his observations and draws conclusions from them by calculation. She has reduced the observations of ten thousand stars, and prepared a work of three hundred pages of horary tables - an immense work for her age and sex. They are incorporated in my 'Abrégé de Navigation.' She is one of the rare women who have written scientific books. She has published tables for finding the time at sea by altitude of the sun and stars. These tables were printed in 1791 by the order of the National Assembly. ... In 1799 she published a catalogue of ten thousand stars, reduced and calculated.

Amélie and Michel Lefrançais de Lalande had two children. A daughter was born on 20 January 1790, the day the comet discovered by Caroline Herschel was first visible in Paris. They named their daughter Caroline after Caroline Herschel. They also had a son whom they named Isaac after another of Amélie's heroes, Isaac Newton.

As Lalande explains in the above quote, Amélie Lefrançais de Lalande's tables were appended to his famous work Abrégé de navigation historique, théorétique, et practique, avec des tables horaires which was published in 1793. Her work was also incorporated into Connaissance des temps which Lalande edited from 1794 until his death in 1807. In [1] Alic writes that Amélie Lefrançais de Lalande:-

... lectured on astronomy in Paris, and worked independently as well as in collaboration with her husband.

We have not yet discovered any details regarding her work as a lecturer. We hope to be able to find more information and improve this biography at a later date.

Article by: J J O'Connor and E F Robertson

December 2008


MacTutor History of Mathematics
[http://www-history.mcs.st-andrews.ac.uk/Biographies/Harlay.html]