[en] The aim of the present report is to present certain observations and to give the results obtained during the period from july the 1^st 1958 to july the 1^st 1960. The main operations carried out during this period were, chronologically: - From july the 5^th to october the 18^th 1958: preparation and execution of the first annealing of the graphite. - From dec. the 15^th 1958 to july the 15^th 1959: a discharging campaign which resulted in the complete renewal of the fuel elements. During the monthly stoppages of this campaign, it was possible to make certain observations concerning the packing of the graphite, while at the same time measurements of the temperature of the element cans were made at an increased number of points. - From september the 25^th 1959 to december the 9^th 1959: preparation and execution of the second annealing. At the end of the annealing, the thorium lattice was modified and extra thermocouples were installed for measuring the temperature of the body of the graphite. An apparatus was built for measuring the radial flux. - From december the 9^th 1959 to july 1960: a continuous operation campaign, with a minimum of stoppages. The experimental results are re-assembled, independently of their chronological order, under three main headings which describe the reactors history: - continuous operation, - discharges, - annealing of the reactor. (author)