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In 1862 the settlement of Obock, on the French Somali coast, was commenced and its centenary was commemorated by a 100 franc stamp showing a gunboat of the period, off the settlement. Amiral Adam informs me that the vessel must be the French Despatch vessel Forbin; she was on the Indian Ocean station in 1862 and was the only warship which could possibly be present at Oblock at the time.
A wooden screw ship of 1,130 tons displacement, her armament at that time consisted of two 16 c.m. (6 in.) and two 14 cm. (5.5in.) guns. She was taken off the Navy List on July 7, 1884, and was converted into a training ship for stokers at Lorient. Renamed Fournaise in 1885, she was ultimately broken up in 1896.
French Somali Coast SG453 Sea Breezes 6/66

Built as a wooden hulled screw aviso (1st class) at Brest for the French Navy.
27 August 1857 laid down.
04 May 1859 launched as the FORBIN, three sisters.
Dim. 63.29 m. length of deck, length on waterline 61.00m. beam 10.04, maximum draught 4.44m.
Powered by one 2-cyl. Mazeline steam engine, 813 ihp., speed 11.17 knots.
Bunker capacity 220 ton coal.
Armament when built 4 – 16cm guns, later a few times changed.
Crew 136.
10 July 1859 commissioned.

French Somalia Coast 1962 100f. sg 453, scott C25
Source: http://www.shipscribe.com/marvap/431b.html