| Pierre
Louis Moreau de Maupertuis
(1698-1759), the French philosopher, mathematician and geodesist, has
inscribed his name in the history of our planet for all time. He was sent
out by the French Academy of Sciences to determine, with as exact measurements
as possible, the shape of the Earth at the poles. This took place between
1736-1737, when his expedition spent almost exactly one year in the area
of the Gulf of Bothnia. The measurements were performed in the northernmost
regions of Europe, in areas that people in the cultural centres of Europe
considered more or less inhabitable: namely, immediately north and south
of the Arctic Circle in Sweden. Formerly so strange names in North Scandinavia
such as Tornio and the Torne River became suddenly familiar, not only
to a handful of scientists from faraway France, but were also added, together
with a host of other exotically-intoned Finnish names of villages and
mountains, to the accounts that were subsequently written by the leader
of the expedition himself, and by the accompanying clergyman and chronicler,
the abbot Reignard Outhier (1694-1774).
The reason for this great interest in the shape of the northern areas was the scientific brouhaha that had developed between adherents of the French philosopher René Descartes (1596-1650) and those of the English scientist Isaac Newton (1642-1724). According to the Cartesian vortextheory, the Earth, by spinning on its own axis, take the shape of a lemon, i.e. pointed toward the poles. Newtonian opinion was diametrically opposed. Centrifugal force leads to the enormous mass of the Earth swelling out at the equator, flattening the poles, and giving the Earth a similar shape to that of an orange. Maupertuis and his accompanying experts were now to finally determine who was right, through detailed measurements and comparison of meridians. If the length of a meridian in the vicinity of the Arctic Circle was longer than a degree along the same meridian in France, or close to the equator, this would confirm Newton's "Orange theory"; if the opposite were true, it would confirm Cartesius' "Lemon theory". There were objects for comparison in France, where a large number of measurements had already been performed, and besides that results were awaited from what is now Ecuador in South America, where a similar expedition had been sent in 1735. Maupertuis was an adherent to Newton, like his fellow travellers, among whom there were another three French scholars - Claude Clairaut, Charles le Monnier and Louis Camus. There was also a secretary, an artist, and the Swedish scientist Anders Celsius, who all arrived at Tornio around midsummer in 1736, and were accommodated in the homes of local citizens. A further participant joined them - Anders Hellant, a local man with specialised knowledge and their interpreter. He was indeed the only person in the whole vast province who had knowledge of both French and Finnish. Finnish was the vernacular all along the river valley. Now the job was to use the terrain and countryside to systematically build up a network of triangles starting from the church steeple in Tornio in the south, and the mountain of Kittisvaara near Pello town, just over 100 kms further north. Ten mountaintops, in a straight line, were cleared of all trees, and cones built of barked tree trunks were set up so as to be visible between adjacent mountains. This gave the system of triangles that connected the two extremities of the area. It was a very eventful project, in the middle of summer, among myriads of mosquitoes, travelling sometimes on foot across bogs and marshes, sometimes shooting rapids in rowing boats. The detailed measurement of the triangle's base was done around Christmas of 1736 in bitterly cold weather by two measuring groups, whose results were so exact that they differed by no more than four inches (approx. 10 cms.) The Frenchmen spent the winter in Tornio, where they led a lively social life. Maupertuis was a popular socialite, who recited his own poems and accompanied himself on the guitar. The company left Tornio at midsummer in 1737. During this time, the two daughters of the merchant Planström that still lived at home had fallen in love with two of the elegant gentlemen and travelled after them all the way to Paris. When Maupertuis eventually presented his findings in the book La figure de la Terre in 1738, the Planström sisters had already arrived and had aroused a great deal of interest in the salons of Paris. For want of a better argument, Maupertuis' scientific adversaries seized the opportunity to make a scandal of the whole expedition, by asserting that the participants had merely been indulging in frolics during their stay in the north. As regards the main issuse, however, Maupertuis was proven right; or as Voltaire expressed it, "he flattened The Cassinis as well as the Earth". Cassini the elder and the younger were respectively head of the Paris Observatory and a supporter of the Lemon Theory. Cassini now admitted defeat.
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