Pacific Airfield Control Tower Signals

[30sqnatc]

Version 3 by tankienz, on Flickr

I'm adding this control tower to my airfield diorama. It has a mast which I assume is to signal aircraft like the two pictures below the first with 'one ball' and second with 'two balls' displayed.

bomberthree_tower by tankienz, on Flickr

stirling-control-tower by tankienz, on Flickr

Where they signals? If so what do they mean? Would the ball be lit internally for night operations?

Or am I totally off track and they are met balloons about to be launched

Paul

[tbf25o4]

I'm pretty sure they indicate to aircraft that had radio failure which runway was in use, remembering that most of those pacific island strips only had a single runway, so one ball indicated one direction
and two balls the other

[30sqnatc]

Thanks. Sorry I missed your reply.

Paul