Mystery Nautical item???
 

I know that this isn't really ethnographic, but some of you guys have been around for hundreds of years, so I thought you might know what it is.
It reminds me of the old sound tubes used on Steam Shps where the bridge would communicate with the engine room; am I close?

I think you are on the right track, as the translation from Spanish reads Captains/Commanders Cabin.
I assume that that is a whistle, at the top?...and the item itself is a speaking tube attachment of some sort.
Stu

You are correct, that is a whistle on top. Do you know how long these were used; were they still in use on the old WW2 Liberty Steam Ships. Mine has a hinge that seems original;I'm not sure as to the application.

Sorry but I have no idea as to the period that these were used but I would have thought probably up to (at least) WW2. I seem to recall that similar "speaking tubes" appeared in movies related to WW2 and earlier naval activity.
I would assume that they would have been replaced by internal radio communication.
Hopefully some "old salt" might see this post and comment...
Stu

When I first went to sea many of the ships I sailed on were old, built in the 1950s just after WW2. They were all fitted with sound powered emergency phones as a back up system - they work with no electricity or battery - positioned at all important locations. This technology according to wiki came in around 1944 so it is likely that sound tubes as a back up were still in use during most of WW2.

The whistle obviously attracts attention to the tube, but whether you could blow a blast down to operate the whistle from the other end I don't know. The whistle shown does not seem to have a mouthpiece. I'm also not sure how far the tubes could operate. It may have been fine for say Bridge to Captain's cabin but I doubt it would have worked to the engine room half a ship away. I would guess that, in this example, the Bridge could operate something - a bellows perhaps - that sounded the whistle in the Captain's cabin to call him to the Bridge or to alert him to converse on the tube.

Incidentally it is reported that during the attack on the USS Cole in 2000 with all power lost and communications down the sound powered telephone system remained the only working comm system.

Most probably, i would say ... or for sure :o .

Thanks for the great information guys. I actually blew on the whistle and to my surprise, it actually worked quite well; I think it was to alert the other end that a conversation was forthcoming. As kahnjar1 stated, this was in the Commander's Room, so maybe a conversation could be heard, but going to the Engine Room of a Steam Ship, even in the Control Room, I find it hard to believe that a conversation could be heard above the noise. That being said, I have since read that these tubes could be as long as 300' and that they have been in existence since the time of Admiral Nelson; maybe an old play on the tin can and string conversation.

I would guess, not properly for an actual conversation but for giving/receiving (loud) short orders ...