Letter from the Paris Balloon drop 1870. It has 'Par Ballon Monte' written along the left hand side. It has a stamp and cancellation markings on the left hand side.
Underneath the letter is a label from the first mailbag dropped at Cologne 1918, during the occupation.'OHMS to be dropped at Cologne Home Depot No Date' is written on the label. (POST 118/1056, The Postal Museum collection)
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