Hello Paul
I have only just picked up your query and I have to admit there will be someone in our Society who knows more than me. Having said that I can give you the following information.
France had a post office in Tripoli (Lebanon) from 1852 to August 1913 and in Tripoli (Libya) from 1880 to 1913. I can only add something about POs in the Ottoman Empire which would include Tripoli in Lebanon.
In the Ottoman Empire there were post offices in various cities run by France between 1812 and 1923. France was one of nine countries that had negotiated "Capitulations" with the Ottomans, various extra-territorial rights in exchange for trade opportunities. In the case of mail, the country’s purpose was to facilitate communication between business interests at home and agents throughout the Middle East. The system came to end with the Treaty of Lausanne in 1923.
Originally, the post office used postage stamps of France, but these were denominated in centimes and francs instead of the local piasters, so beginning in 1885, some French stamps were surcharged in piasters, at a rate of four piasters to the franc.
World War I forced the closure of all the post offices on 13 October 1914 but some reopened afterwards..
Mail services at the French Post Office were not exclusively used by the French. If a French boat was sailing before a British one then the letter would be handed over before the sailing. Most likely the letter would have been landed at Marseille, thence to Paris by train or onward delivery to Great Britain. A French stamp with or without a local overprint would suffice. The Sower stamp was the current definitive at the time of your cover.
Hope this helps
Mick Bister
