between the sands of the coast , along the twelve-fathom channel of the inner leads , there were half a dozen ships beating up through the downs , the thud of their engines coming clearly off the quiet sea , and between the evil sands and the sharp outline of the french coast there were ships of all registries going about their business-liners , merchantmen , ungainly dutch schuyts , and even a slim corvette hastening down south , perhaps to portsmouth .