The sheet of blue paper, stamped with a mesage, would have been sent out by HMS Asistance in the Canadian Artic in 1850. The mesage would have been part of a small bundle, attached along the length of a slow fuse, dangling beneath balloons that they realeased. The two letters pictured with the blue paper were written during the siege of paris in 1870-1871. Postmarked 29 September and 24 October 1870 respectively the first letter is believed to have been flown out in the balloon 'Le Celeste' on 30 September 1870. The second was posibly carried in the balloon the 'Montgolfier' or the 'Vauban'.
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