DEGREE MEASUREMENT EXPEDITION:
The measuring instruments
The measurements
The measurement sites

The degree measurement expedition

The French king Louis XV decreed that the French Academy of Science send an expedition to Peru to explore the flattening of the earth. Another expedition led by de Maupertuis was sent to the Arctic Circle. The expedition followed a suggestion made by the Swedish Anders Celcius and set out for the Tornionlaakso Valley in Sweden. The expedition left France in April in 1736 and they stopped for a few days in Stockholm, the then capital of Kingdom of Sweden. The French party arrived in Tornio from Kalix on the 19th of June 1736 and they left for their return journey on the 10th of June in 1737. The measurements took just slightly less than a year to carry out

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The party comprised of Pierre-Louis de Maupertuis, astronomer and mathematician, mathematicians Charles Etienne Louis Camus and Alexis Claude Clairaut, astronomer Pierre-Charles Le Monnier, draughtsman M d.Herbelot, secretary M. Sommereux and abbé Réginald Outhier. Professor Anders Celcius joined the party in Sweden. Anders Hellant, born in Pello, served as the interpreter of the party.

To carry out the measurement a line of approximately one degree in the north - south axis was needed as a base for triangular measurements in the vicinity. De Maupertuis first planned to carry out the measurements in the archipelago of the Gulf of Bothnia. He found out, however, that the islands were too low for triangular measurement. Headmaster Wegelius from Tornio suggested the river Tornionjoki and the fells around it as ideal experiment area. His suggestion was put into practice. The soldiers Lieutenant Colonel Du Rietz had commanded to de Maupertuis' service were helping in the boat transport, the carrying of instruments and other practical chores.