Hi there, The lever shown above is from the left side of a Marconi morse key, Similar ones were used on Titanic although they had two. There are many online pictures of that particular key but they need searching. I have made a copy of this key so I am very familiar with it. The lever is actually a hinged cut out safety switch which was surprisingly supposed to be connected to the deckhead by a cord to the small brass loop on the side, so that the switch could be found in total darkness. I have only found one picture showing this in place, but I can understand it not being popular with operators. The one shown could easily be the one that Harold Cottam used to speak to Titanic, particularly if he had only one, could also be the reason why it was removed, Keys were normally screwed to the bench.