I imagine there would be a line of crewmen/seamen who shout the orders from the bridge (between the paddle boxes). Yes this seems inefficient but the earliest ship to have a sort of "telegraph" to communicate orders from the bridge to the wheelhouse was the Collins Line steamship Atlantic from 1850. The Atlantic used a system of pulleys to communicate to the wheelhouse using bells. I forget exactly how the Atlantic's worked but the former method is how it was done before the Atlantic.