During the explorations of Pourquoi-Pas?, commanded by Jean Baptiste Charcot, in the Southern Ocean in the period 1908–1910, Ensign R.-E. Godfroy collected, between latitudes 64°09'S and 70°05'S, eleven samples of air, according to instructions given by Muntz and Luné (1911) for measuring the concentrations of CO2 in the atmosphere. The samples were later analysed in the laboratories of the Conservatoire des Arts et Metiers, Paris using basically the same methods as for the samples collected by the French First Polar Year expedition 1882–1883 (Baker 2009). The maximum concentration of CO2 was 255 ppm, the minimum 145 ppm (the sample taken at sea at 69°30'S) and the mean 205 ppm. The average of the concentrations in the samples made by the French first IPY expedition at Bahia Orange was 256ppm and the minimum was 231 ppm.