Scientist of the Day - Jérôme de Lalande
Lock at Gardouch on the Languedoc Canal, detail of engraving, Des canaux de navigation, et spécialement du canal de Languedoc, by Joseph Jérôme Le Français de Lalande, plate 4 at end, 1778 (Linda Hall Library)
Joseph Jérôme Le Français de Lalande, a French astronomer and mathematician, was born on July 11, 1721. Lalande wrote a number of books on astronomy, many of which we have in our collections, but just one on canals. Nevertheless, we are going to focus on the canal book today, because May 20 is not Lalande's birthday, but that of the Languedoc Canal, which opened on May 20, 1681, and which is the subject of Lalande’s book. Moreover, we acquired Lalande’s book, a beautiful folio, just two weeks ago, and this is our first chance to show it off. It is called: Des canaux de navigation, et spécialement du canal de Languedoc (1778).
Portrait of Joseph Jérôme Le Français de Lalande, undated engraving, Smithsonian Libraries (library.si.edu)
The building of the Languedoc canal (now called the Canal du Midi) was THE engineering feat of early modern times. It connected Toulouse in south-central France with the Mediterranean coast to the east, a distance of about 150 miles, and since Toulouse sat on the Garonne River, which was navigable to the Atlantic Ocean, in effect the Languedoc canal joined the east coast of France with the west coast and avoided the Straits of Gibraltar entirely.
Title page, Des canaux de navigation, et spécialement du canal de Languedoc, by Joseph Jérôme Le Français de Lalande, 1778 (Linda Hall Library)
The principal engineer of the Languedoc Canal, Pierre-Paul Riquet, was not an engineer at all but a tax collector favored by Jean-Baptiste Colbert, Louis XIV's finance minister. We wrote a post on Riquet in 2020. It was a COVID post, when I was restricted to just two images, so I had to use quite a few links, but they all still work, and the earlier post will show you some modern views of the Languedoc Canal locks, and two contemporary maps of the path of the canal.
Detail of a wooden lock gate on the Languedoc Canal, engraving, Des canaux de navigation, et spécialement du canal de Languedoc, by Joseph Jérôme Le Français de Lalande, plate 3 at end, 1778 (Linda Hall Library)
The Languedoc canal had to cross a mountain range at an elevation of 620 feet, so it required many locks – some 90 in all. It also required an immense water source to feed the canals, which meant building a huge reservoir at altitude. All of this was accomplished in about 15 years. Riquet had an assistant, François Andréossy, who WAS an engineer, and some have always maintained that Andr éossy was the real genius behind the Languedoc Canal; especially vocal was his grandson, who wrote a book on the canal in 1800 (we have the 1804 enlarged edition), championing his grandfather.
The eight-lock cascade on the Languedoc Canal at Fonseranne, elevation and plan, folding engraving, Des canaux de navigation, et spécialement du canal de Languedoc, by Joseph Jérôme Le Français de Lalande, plate 10 at end, 1778 (Linda Hall Library)
Not so Lalande. It would seem that his principal purpose in writing Des canaux de navigation was to extol Riquet as the creative genius behind the canal. But he enriched his account with 14 large engravings – some of them larger than the book, which is plenty large – and we show 5 of them here, either in detail or in their entirety. There are several bird’s-eye views of the lozenge-shaped locks, and of the wooden gates that closed the locks (first and fourth images). There is one series of 8 locks at Fonseranne that form a cascade (reminding me of the 5-lock cascade on the Erie Canal at Lockport, built 150 years later); a double-page engraving shows both the plan and elevation of the Fonseranne locks (fifth image).
Aqueduct at Cesse on the Languedoc Canal, engraving, Des canaux de navigation, et spécialement du canal de Languedoc, by Joseph Jérôme Le Français de Lalande, plate 11 at end, 1778 (Linda Hall Library)
There were several sites that required aqueducts to carry the canal over rivers. We show a plate of one of those, at Cesse (sixth image). In our first post on Piquet, we linked to a recent photo of that aqueduct; here is that link again. It doesn't look much different from the engraving in Lalande's book. Lalande also included a view of an unusual round lock at Agde, on the Mediterranean, looking rather like the turntable for a roundhouse at a railroad yard (seventh image).
The round lock at Agde on the Languedoc Canal, detail of engraving, Des canaux de navigation, et spécialement du canal de Languedoc, by Joseph Jérôme Le Français de Lalande, plate 7 at end, 1778 (Linda Hall Library)
You may choose Riquet or Andréossy as your Languedoc hero, but a fairly recent book, Impossible Engineering: Technology and Territoriality on the Canal du Midi, by Chandra Mukerji (Princeton Univ. Pr., 2009), suggests that you might be wrong with either choice. The author argues that there was no engineering theory in 17th-century France that would tell you how to build a canal over such rugged terrain, so they had to rely on local artisans and female peasant workers to solve most of the problems that arose, using what she calls a "collective social intelligence" that echoed Roman practices. She makes an intriguing case for those unnamed workers, often women, who usually get left out of accounts of engineering successes.
Portrait of Pierre-Paul Riquet, engraving, undated (canal-du-midi.com)
In our post on Riquet, we showed a statue of Riquet, and a memorial plaque, but no portrait. So we provide one here, as our last image. The portrait shown at the beginning of the post depicts Lalande. If you wonder why I didn’t find a better portrait, I reply, that is the best one out there, as this search on Google Image attests. Lalande was one odd-looking dude.
William B. Ashworth, Jr., Consultant for the History of Science, Linda Hall Library and Associate Professor emeritus, Department of History, University of Missouri-Kansas City. Comments or corrections are welcome; please direct to ashworthw@umkc.edu.
