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The Sultan of Zanzibar's Barge. 
Perhaps you may be interested in the following vessel built in White’s Shipyard in the 1870s.
Over the years I have worked on engineering projects in the Port of Zanzibar on several occasions. Whilst in Zanzibar in 1987 working on the design of port expansions I came across an intriguing looking vessel dumped at the back of one of the cloves godowns (warehouses) in the port which, it transpires, has a rather intriguing story attached. It was a very ornate barge with plush red velvet seats below a canopy and positions for sixteen oarsmen and a coxswain. A plaque affixed to the barge indicated that it was constructed at White’s Shipyard on the Isle of Wight. I suggested to the Zanzibar Ports Corporation that the vessel should be moved to a safer location.
From investigations over a good few years, I have discovered that Sayyid Barghash Bin Said, The Sultan of Zanzibar from 1870 to 1888, was invited to pay a state visit to England in 1875, largely to ensure his pacification after the British Navy actions in subduing the slave trade along the coast of East Africa.
For the Sultan’s reception upon arrival at London Docks, Queen Victoria commissioned the construction of the barge in order that he could be rowed up the Thames to Windsor where he was a guest of the Queen during his stay in England. The Sultan was so impressed with the barge that Queen Victoria presented it to him at the end of his state visit, and it was then shipped out to Zanzibar for his use.
When last in Zanzibar at the end of 1999 I found that the barge had been moved from the cloves godown to the Zanzibar Ports Corporation stores building in order to prevent pilfering of the fittings on the barge.
I would think this vessel is probably one of the oldest surviving examples of White’s 19th century workmanship.
I attach two photographs – one of the barge in use in the late 1800s and the other my picture of the barge in 1999.
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