eBay: Ship's dome light

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=3984486821

Relisted with lower price:

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=7700125847

A ship's "dome" light? As in: when you open the hatch to the pilothouse the light comes on? Like in a car?

I've been on plenty of ships, and while this may have been a light in some ship's passageway or exterior deck, it is in no way, shape or form a navigational light of any sort.

Sherlock, the light is in dome like shape.

These are usually called Cage Lights (more specifically, Cylinder Cage Lights), or sometimes Bulkhead Lights. Usually used on larger ships. That one looks like it might be U.S. Navy issue. Here's a few examples at a nautical supply site, including port and starboard versions, which I had never seen before. I think I've seen these in the decor at Bahooka - I may be wrong though.
http://www.brassandbounty.com/cgi-bin/bnb.cgi?op=view&page=Ship+Lights

Sabu

Yep, those sure are Bulkhead lights or "Deck Lights". If you see red ones it's more than likely that they WERE interior lights since the ships will switch to red light at night. ( Set Dog Zebra!!! ) Just used to love shining the brass cage every morning back in my Seaman days. Now, if they could only find that darn "Smoking Lamp" that was always being extinguished. I think it may have been down by the Prop Wash or Realitive Bearing Grease. You should know about those things Satans Sin!

I am all too familiar with the dreaded "Sea Bat!"

Also may have stood a watch or two for the Mail Buoy.