I can't see how that would work.As a mere skimmer, may I suggest they could be used for taking on fresh water/fuel.
As above, I can't see how that would work for either or why you would need to remotely operate the gun or the planes. They look like smaller versions of the engine room telegraphs we had on the Rusty B, which is why I agree with janners hypothesis.Alternatively:
a. Remote layer & trainer for the foredeck gun,
b. Remote foreplanes & after planes controls for running 'shallow' or trimmed down.
Just had a email back from Eric Andrews, He was Scratcher on the Sidon (same class of Boat for those that don't know) in his opinion they are the engine room telegraphs. Huw, I don't remember Diesel Boats having the Rev counters/indicators.