Trials on the River Thames. "Mimi" in foreground, "Tou-Tou" behind. Lieutenant Cross RNR standing by gun, John & Tom Thornycroft, Port & Starboard respectively. G. Spicer-Simpson in khaki.
The two motorboats HMS Mimi and HMS Toutou were the smallest commissioned vessels in the Royal Navy. Spicer-Simson wanted them named Cat and Dog but chose the French equivalents of Meow and Woof-Woof when his bosses indignantly denied his first choices.
Forty feet long, eight feet in beam, Mimi and Toutou drove their mahogany hulls through the water with 100-horsepower gasoline engines. Three-inch guns mounted forward of their cockpits provided firepower and a great deal of weight, which made the boats tricky to pilot.
Image courtesy of War is Boring
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