What's that thing in the window?

Question

This is probably a pretty dumb question, but what is the circular device I constantly see mounted in the windows of a ship's bridge?

Answer 1

THE STEERING WHEEL!

Answer 2

the port (window) can spin real fast when it is raining so the water that lands on it spins off and you can see out the window.  the circle thing is the motor for the device that spins the window (port).

Answer 3

The circular area is for seeing in rain as the area spins very fast so the centrifical force keeps the sight area clear better that the auto type windshield wipers.

Herman

Answer 4

Not only water, but ice. Some of these are heated, so the warmed glass won't allow ice to stick and the spinning motion keeps it clear.